Background Dietary lysine and apparent nitrogen-corrected metabolizable energy(AMEn)are two key variables affecting the production of bre eder hens.In this study,the effe cts and interactions of lysine and AMEn on yel...Background Dietary lysine and apparent nitrogen-corrected metabolizable energy(AMEn)are two key variables affecting the production of bre eder hens.In this study,the effe cts and interactions of lysine and AMEn on yellowfeathered broiler breeder hens were investigated.A total of 72030-week-old breeder hens were fed in a 5(lysine:0.56%,0,68%,0.80%,0,92%,and 1.04%)×2(AMEn:11.50 and 11.10 MJ/kg)factorial arrangement for 12 weeks.The productive performance,reproductive traits,biochemical variables of breeder hense the amino acid concentration and quality of eggs,and the growth performance of offspring broilers were determined.Result(1)Dietary lysine had quadratic effects(P<0.05)on laying rate,average daily egg mass and feed intake/egg mass of breeder hens;birds with 11.50 MJ/kg AMEn(high AMEn)had higher(P<0.05)BW than those with 11.10MJ/kg AMEn(low AMEn);(2)dietary lysine significantly affected on the relative ovarian weight(quadratic and linear),and numbers of large yellow follicles(LYF,quadratic);birds with high AMEn had longer fallopian tube and more LYF than those with low AMEn(P<0.05);(3)dietary lysine had significant effects(linear and quadratic)on eggshell thickness and shell strength of eggs from breeder hens;birds with high AMEn had thinner eggshells and deeper yolk color than those with low AMEn(P<0.05);(4)there were higher(P<0.05)contents of protein and concentrations of all measured animo acids(AAs)in eggs from birds fed low AMEn;(5)supplementation with high AMEn to breeder hens significantly increased the hatchability of fertilized eggs;(6)neither dietary lysine level or AMEn afofected growth performance of offspring broilers;(7)both dietary lysine level and AMEn significantly affected gonadotropin concentrations and biochemical variables of breeder hens.Conclusions Dietary lysine had significant influences on productive performance,reproductive traits,and egg quality of yellow-feathered breeder hens.Based on productive performance,the optimal levels of dietary lysine were 0.81%to 0.83%,while 0.71%to 72%lysine was enough to obtain the best quality of breeding eggs.High AMEn was more beneficial to breeder hens for reproductive traits and hatchability of the fertilized eggs,while it showed detrimental epfrfects on eggshell thickness and AA concentrations of breeding eggs.展开更多
Background: The study aimed to determine the apparent total tract digestibility coefficients(ATTDC) of nutrients, the apparent metabolizable energy(AME and AMEn) and the amino acid(AA) apparent ileal digestibility coe...Background: The study aimed to determine the apparent total tract digestibility coefficients(ATTDC) of nutrients, the apparent metabolizable energy(AME and AMEn) and the amino acid(AA) apparent ileal digestibility coefficients(AIDC)of a partially defatted(BSFp) and a highly defatted(BSFh) black soldier fly larvae meal. The experimental diets were: a basal diet and two diets prepared by substituting 250 g/kg(w/w) of the basal diet with BSFp or BSFh, respectively.Results: Significant differences were found between BSFp and BSFh meals for ATTDC of the nutrients: BSFp resulted more digestible than BSFh, except for ATTDC of CP which did not differed between meals, while a statistical trend was observed for ATTDC of DM and EE. The AME and AMEn values were significantly(P < 0.05) different between the two BSF meals, with higher levels for BSFp(16.25 and 14.87 MJ/kg DM, respectively). The AIDC of the AA in BSFp ranged from 0.44 to 0.92, while in BSFh they ranged from 0.45 to 0.99. No significant differences were observed for the AA digestibility(0.77 and 0.80 for BSFp and BSFh, respectively), except for glutamic acid, proline and serine that were more digestible in the BSFh meal(P < 0.05).Conclusions: Defatted BSF meals can be considered as an excellent source of AME and digestible AA for broilers with a better efficient nutrient digestion. These considerations suggested the effective utilization of defatted BSF larvae meal in poultry feed formulation.展开更多
A total of 335 lactating sows （Landrace x Large White） were used in two experiments to determine the optimum ratio of standardized ileal digestible lysine （SID-Lys） to metabolizable energy （ME） for mixed parity ...A total of 335 lactating sows （Landrace x Large White） were used in two experiments to determine the optimum ratio of standardized ileal digestible lysine （SID-Lys） to metabolizable energy （ME） for mixed parity sows during lactation. In Exp. 1, 185 sows （weighing an average of 256.2 ± 6.5 kg and having an average parity of 3.4 ± 0.3） were allocated to one of six experimental diets in a completely randomized block design within parity groups （1, 2, and 3＋）. The experimental diets were formulated to contain 3.06, 3.16, 3.20, 3.25, 3.30 or 3.40 Mcal/kg of ME and each diet was fed to the sows throughout a 28 day lactation. All diets provided a similar SID-lysine level （0.86%）. As a result, the diets provided a SID-Lys：ME ratio of 2.81, 2.72, 2.69, 2.65, 2.61 or 2.53 g/Mcal ME. Sow feed intake was significantly （P 〈 0.01） affected by the energy content of the diet as well as by sow parity. Using regression analysis, feed intake was shown to be maximized at 3.25, 3.21, 3.21 and 3.21 Mcal/kg of ME for parity 1, 2, 3＋ sows and the entire cohort of sows respectively （quadratic; P 〈 0.01）. In addition, the result of feed intake can be expressed as 2.65, 2.69, 2.69 and 2.68 g/Mcal based on analysis of SID-Lys：ME ratio. Litter weight gain was affected by dietary treatment for parity 3＋ sows and the entire cohort （P 〈 0.01）. Based on regression analysis, litter weight gain was maximized at 3.25 and 3.24 Mcal/kg of ME for parity 3＋ （quadratic; P 〈 0.01） and the entire cohort （quadratic; P 〈 0.01）. Similarly, the result of litter weight gain could be expressed as 2.65 and 2.66 g/Mcal of SID- Lys：ME ratio. Therefore, 3.25 Mcal/kg of ME was selected for Exp. 2 in which 150 sows （weighing 254.6 ± 7.3 kg and having an average parity of 3.4 ± 0.4） were allocated to one of five treatments in a completely randomized block design within parity （1, 2, and 3＋）. The experimental diets were formulated to contain 2.1, 2.4, 2.7, 3.0 or 3.3 g/Mcal of SID-Lys：ME ratio with all diets providing 3.25 Mcal/kg of ME. The diets were fed to the sows throughout a 28 day lactation. Sow body weight loss was affected by dietary treatment （parity 3＋ sows, P = 0.02; entire cohort, P 〈 0.01） and by sow parity （P 〈 0.01）. Litter weight at weaning and litter weight gain were affected by dietary treatment for parity 1, 2, 3＋ sows and the entire cohort （P 〈 0.01） as well as by sow parity （P 〈 0.01）. Plasma urea nitrogen （P 〈 0.01）, creatinine （P 〈 0.01） and non-esterifide fatty acids （P = 0.04） were decreased as the SID-Lys：ME ratio of the diet increased. Insulin-like growth factor-1 （P = 0.02）, estradiol （P 〈 0.01） and luteinizing hormone （P = 0.02） were increased as the SID-Lys：ME ratio in diet increased. Based on a broken-line model, the estimated SID-Lys： ME ratio to maximize litter weight gain was estimated to be 3.05 g/Mcal.展开更多
Background: Improving the feed efficiency would increase profitability for producers while also reducing the environmental footprint of livestock production. This study was conducted to investigate the relationships a...Background: Improving the feed efficiency would increase profitability for producers while also reducing the environmental footprint of livestock production. This study was conducted to investigate the relationships among feed efficiency traits and metabolizable efficiency traits in 180 male broilers. Significant loci and genes affecting the metabolizable efficiency traits were explored with an imputation-based genome-wide association study. The traits measured or calculated comprised three growth traits, five feed efficiency related traits, and nine metabolizable efficiency traits.Results: The residual feed intake(RFI) showed moderate to high and positive phenotypic correlations with eight other traits measured, including average daily feed intake(ADFI), dry excreta weight(DEW), gross energy excretion(GEE), crude protein excretion(CPE), metabolizable dry matter(MDM), nitrogen corrected apparent metabolizable energy(AMEn), abdominal fat weight(Ab F), and percentage of abdominal fat(Ab P). Greater correlations were observed between growth traits and the feed conversion ratio(FCR) than RFI. In addition, the RFI, FCR, ADFI, DEW,GEE, CPE, MDM, AMEn, Ab F, and Ab P were lower in low-RFI birds than high-RFI birds(P < 0.01 or P < 0.05), whereas the coefficients of MDM and MCP of low-RFI birds were greater than those of high-RFI birds(P < 0.01). Five narrow QTLs for metabolizable efficiency traits were detected, including one 82.46-kb region for DEW and GEE on Gallus gallus chromosome(GGA) 26, one 120.13-kb region for MDM and AMEn on GGA1, one 691.25-kb region for the coefficients of MDM and AMEn on GGA5, one region for the coefficients of MDM and MCP on GGA2(103.45–103.53 Mb), and one 690.50-kb region for the coefficient of MCP on GGA14. Linkage disequilibrium(LD) analysis indicated that the five regions contained high LD blocks, as well as the genes chromosome 26 C6 orf106 homolog(C26 H6 orf106), LOC396098, SH3 and multiple ankyrin repeat domains 2(SHANK2), ETS homologous factor(EHF), and histamine receptor H3-like(HRH3 L), which are known to be involved in the regulation of neurodevelopment, cell proliferation and differentiation, and food intake.Conclusions: Selection for low RFI significantly decreased chicken feed intake, excreta output, and abdominal fat deposition, and increased nutrient digestibility without changing the weight gain. Five novel QTL regions involved in the control of metabolizable efficiency in chickens were identified. These results, combined through nutritional and genetic approaches, should facilitate novel insights into improving feed efficiency in poultry and other species.展开更多
Background： The nutrient composition of corn is variable. To prevent unforeseen reductions in growth performance, grading and analytical methods are used to minimize nutrient variability between calculated and analyz...Background： The nutrient composition of corn is variable. To prevent unforeseen reductions in growth performance, grading and analytical methods are used to minimize nutrient variability between calculated and analyzed values. This experiment was carried out to define the sources of variation in the energy content of corn and to develop a practical method to accurately estimate the digestible energy （DE） and metabolisable energy （ME） content of individual corn samples for growing pigs. Twenty samples were taken from each of five provinces in China （Jilin, Hebei, Shandong, Liaoning, and Henan） to obtain a range of quality. Results： The DE and ME contents of the 100 corn samples were measured in 3.5.3 ±1.92 kg growing pigs （six pigs per corn sample）. Sixty corn samples were used to build the prediction model; the remaining forty samples were used to test the suitability of these models. The chemical composition of each corn sample was determined, and the results were used to establish prediction equations for DE or ME content from chemical characteristics. The mean DE and ME content of the 100 samples were 4,053 and 3,923 kcal/kg （dry matter basis）, respectively. The physical characteristics were determined, as well, and the results indicated that the bulk weight and 1,000-kernel weight were not associated with energy content. The DE and ME values could be accurately predicted from chemical characteristics. The best fit equations were as follows： DE, kcal/kg of DM = 1062.68 ＋ （49.72 ×EE） ＋ （0.54 × GE） ＋ （9.1 ] x starch）, with R^2 = 0.62, residual standard deviation （RSD） = 48 kcal/kg, and P 〈 0.01; ME, kcal/kg of dry matter basis （DM） = 671.54 ＋ （0.89 ×DE） - （5.57 × NDF） - （191.39 ×ash）, with R^2 = 0.87, RSD = 18 kcal/kg, and P〈 0.01. Conclusion： This experiment confirms the large variation in the energy content of corn, describes the factors that influence this variation, and presents equations based on chemical measurements that may be used to predict the DE and ME content of individual corn samples.展开更多
A total of 2,121 growing-finishing pigs （Duroc × Landrace ×Large White） were utilized in six experiments conducted to determine the effects of different ratios of standardized ileal digestible lysine （SID...A total of 2,121 growing-finishing pigs （Duroc × Landrace ×Large White） were utilized in six experiments conducted to determine the effects of different ratios of standardized ileal digestible lysine （SID-Lys） to metabolizable energy （ME） on the performance and carcass characteristics of growing-finishing pigs. Exps. 1 （30 to 50 kg）, 2 （52 to 70 kg） and 3 （81 to 104 kg） were conducted to find an optimum ME level and then this level was used in Exps. 4 （29 to 47 kg）, 5 （54 to 76 kg） and 6 （84 to 109 kg） to test the response of pigs to different ratios of SID-Lys：ME. In Exps.1 to 3, four treatments were used consisting of diets with a formulated ME content of 3.1, 3.2, 3.3 or 3.4 in Exps. I and 2 while Exp. 3 used 3.05, 3.1 S, 3.25 or 3.35 Mcal/kg. A constant SID-Lys：ME ratio of 2.6, 2.3 or 2.0 g/Mcal was used in Exps. 1, 2 and 3, respectively. Weight gain was significantly increased with increasing energy level in Exp.1 while weight gain was unaltered in Exps. 2 and 3. For all three experiments, feed intake was decreased （P 〈 0.05） and feed efficiency was improved （P 〈 0.05） with increasing energy level. Tenth rib back fat thickness linearly increased （P 〈 0.05） with increasing energy level, in Exps. 4 to 6, five treatments were used consisting of diets with a SID-Lys：ME ratio of 2.4, 2.6, 2.8, 3.0 or 3.2 in Exp. 1, 2.1, 2.3, 2.5, 2.7, 2.9 or 3.2 in Exp. 2 and 1.8, 2.0, 2.2, 2.4, or 2.6 in Exp. 3. A constant ME level 3.2, 3.2 and 3.05 Mcal/kg was used in Exps. 1, 2 and 3, respectively （selected based on the results of weight gain）. For all three experiments, weight gain increased （P 〈 0.05） and feed efficiency improved linearly （P 〈 0.05） as the SID-Lys：ME ratio increased. Tenth rib back fat thickness linearly decreased （P 〈 0.0,5） as the SID-Lys：ME ratio increased. Based on a straight broken-line model, the estimated SID-Lys：ME ratio to maximize weight gain was 3.0, 2.43 and 2.2 for 29 to 47, 54 to76 and 84 to 109 kg of pigs, respectively.展开更多
Background： This study was conducted to evaluate the apparent metabolizable energy （AME） and true metabolizable energy （TME） contents in 30 sources of corn distillers dried grains with solubles （DDGS） in adult ...Background： This study was conducted to evaluate the apparent metabolizable energy （AME） and true metabolizable energy （TME） contents in 30 sources of corn distillers dried grains with solubles （DDGS） in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical composition and color score. Methods： Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy （ME） contents, measured for color score and chemical composition （crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber）, to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed （50 g） to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses. Results： Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content （-0.64, P 〈 0.0]） and between ME and yellowness score （0.39, P 〈 0.05） of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME = 6.57111 ＋ 0.5]475 GE - 0.10003 NDF ＋ 0.1 3380 ADF ＋ 0.07057 fat - 0.57029 ash - 0.02437 L （R^2 = 0.70）. The best-fit regression equation for TME content of DDGS was TME = 7.92283 ＋ 0.51475 GE - 0.10003 NDF ＋ 0.13380 ADF ＋ 0.07057 fat - 0.57029 ash - 0.02437 L （R2 = 0.70）. Conclusions： This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.展开更多
Background： The ability of near-infrared reflectance spectroscopy（NIRS） to determine the digestible energy（DE）and metabolizable energy（ME） content of corn fed to growing pigs was tested. One hundred and sevente...Background： The ability of near-infrared reflectance spectroscopy（NIRS） to determine the digestible energy（DE）and metabolizable energy（ME） content of corn fed to growing pigs was tested. One hundred and seventeen corn samples, comprising different planting regions and varieties were collected from all over China in a three-year period. The samples were randomly split into a calibration set（n = 88） and a validation set（n = 29）. The actual and calculated DE and ME content of the corn samples was determined by digestion-metabolism experiments and the prediction equations of Noblet and Perez（J Anim Sci. 71：3389–98,1993）. The samples were then subjected to NIRS scanning and calibrations were performed by the modified partial least square（MPLS） regression method based on77 different spectral pre-treatments. The NIRS equations based on the actually determined and calculated DE and ME were built separately and then validated using validation samples.Results： The NIRS equations obtained from actually determined DE, the coefficient of determination for calibration（RSQcal）, cross-validation（R^2CV）, and validation（RSQv） were 0.89, 0.87 and 0.86, and these values for determined ME were 0.87, 0.86 and 0.86. For the NIRS equations built from calculated DE, the RSQcal, R^2CV, and RSQvvalues were 0.88, 0.85 and 0.84, and these values for calculated ME were 0.86, 0.84 and 0.82. Except for the equation based on calculated ME（RPD_v= 2.38, 〈 2.50）, the other three equations built from actually determined energy and calculated DE produced good prediction performance（RPD_vranging from 2.53 to 2.69, 〉 2.50） when applied to validation samples.Conclusion： These results indicate that NIRS can be used as a quantitative method for the rapid determination of the available energy in corn fed to growing pigs, and the NIRS equations based on the actually determined energy produced better predictive performance than those built from calculated energy values.展开更多
Background： Dorper is an important breed for meat purpose and widely used in the livestock industry of the world.However, the protein requirement of Dorper crossbred has not been investigated. The current paper repor...Background： Dorper is an important breed for meat purpose and widely used in the livestock industry of the world.However, the protein requirement of Dorper crossbred has not been investigated. The current paper reports the net protein（NP） and metabolizable protein（MP） requirements of Dorper crossbred ram lambs from 20 to 35 kg BW.Methods： Thirty-five Dorper × thin-tailed Han crossbred lambs weaned at approximately 50 d of age（20.3 ± 2.15 kg of BW） were used. Seven lambs of 25 kg BW were slaughtered as the baseline animals at the start of the trial. An intermediate group of seven randomly selected lambs fed ad libitum was slaughtered at 28.6 kg BW. The remaining 21 lambs were randomly divided into three levels of dry matter intake： ad libitum or 70% or 40% of ad libitum intake. Those lambs were slaughtered when the lambs fed ad libitum reached 35 kg BW. Total body N and N retention were measured.Results： The daily NP and MP requirements for maintenance were 1.89 and 4.52 g/kg metabolic shrunk BW（SBW0.75）.The partial efficiency of MP utilization for maintenance was 0.42. The NP requirement for growth ranged from 12.1 to 43.5 g/d, for the lambs gaining 100 to 350 g/d, and the partial efficiency of MP utilization for growth was 0.86.Conclusions： The NP and MP requirements for the maintenance and growth of Dorper crossbred male lambs were lower than the recommendations of American and British nutritional systems.展开更多
A total of 480 nursery pigs （Duroc x Landrace x Large White） were utilized in two experiments conducted to determine the effects of different ratios of standardized ileal digestible lysine （SID- Lys） to metaboliza...A total of 480 nursery pigs （Duroc x Landrace x Large White） were utilized in two experiments conducted to determine the effects of different ratios of standardized ileal digestible lysine （SID- Lys） to metabolizable energy （ME） ratio on the performance, nutrient digestibility, plasma urea nitrogen （PUN） ,and plasma free amino acids of 10 to 28 kg pigs. In Exp. 1, 192 pigs （ 10.58 kg） were assigned to one of four treatments. The treatments consisted of diets with a ME content of 3.2, 3.25, 3.3, or 3.35 Mcal/kg with a constant SID-Lys：ME ratio of 3.7 g/Mcal. The experiment lasted 28 days. Pigs which were fed the diets containing 3.3 and 3.35 Mcal/kg ME had lower feed intakes （ P 〈 0.05）than those fed 3.2 Mcal/kg. Feed efficiency was linearly improved with increasing dietary ME （ P 〈0.05）. Increasing the dietary ME level also increased （P 〈0.05 ） dry matter and energy digestibility. Therefore,3.3 Mcal/kg ME was selected for Exp. 2 in which 288 pigs （ 10.60 kg） were assigned to one of six treatments. Treatments consisted of SID-Lys： ME ratios of 3.1,3.3,3.5,3.7,3.9, or 4.1 g/Mcal with all diets providing 3.3 Mcal of ME/kg. Weight gain and feed efficiency were increased （P 〈0.05 ） as the SID-Lys：ME ratio in diet increased. Based on a straight broken-line model ,the estimated SID-Lys：ME ratio to maximize weight gain was 3.74.展开更多
[ Objective] To investigate the effects of different levels of metabolizable energy and crude protein on egg laying performance and hatch- ing efficiency in Magang geese. [Method] The healthy Magang geese at 2 years o...[ Objective] To investigate the effects of different levels of metabolizable energy and crude protein on egg laying performance and hatch- ing efficiency in Magang geese. [Method] The healthy Magang geese at 2 years old were randomly assigned into four groups, group Ⅰ, group Ⅱ, group Ⅲ and control group. They were fed with diets at different levels of metabolizable energy and crude protein, and then their eggs were collect- ed and hatched. During the test, their health was observed, and the egg weight, egg yield and hatching rate were recorded. [ Result] The average egg laying rates and average egg weight were significantly higher in the group Ⅰ, group Ⅱ and group Ⅲ than in the control group. The hatchable egg rates and egg fertilization rates of the group Ⅰ, group Ⅱ and group Ⅲ were also increased, and significance was found between the group Ⅲ and the other group （P 〈 0.05）. The feed costs of the three test groups were lower than that of the control group, and the feed cost was higher in the group Ⅲ than that in the group Ⅰ and Ⅱ. [ Conclusion] The levels of metabolizable energy and crude protein in diet have significant effects on laying performance and hatching efficiency in Magang geese.展开更多
The aim of this study was to determine the apparent （AME） ＆ true （TMEn） metabolizable energy as well as the crude protein （CP） ＆ amino acid （AA） total tract （by excreta collection） digestibility （bioavail...The aim of this study was to determine the apparent （AME） ＆ true （TMEn） metabolizable energy as well as the crude protein （CP） ＆ amino acid （AA） total tract （by excreta collection） digestibility （bioavailability） of field pea seeds （FPS） of the Greek cultivar ＂Olympos＂. Forty eight broilers were placed in individual cages and randomly allocated into 4 dietary treatments. Birds consumed 80 g/d of either a typical commercial diet or the same diet in which 100, 200 or 300 g/kg had been substituted by ground FPS. The experiment lasted 15 d. Apparent and true CP bioavailability of FPS were significantly decreased （P 〈 0.05） only at the inclusion rate of 300 g/kg. AA bioavailability remained at high levels （-0.80）, with the exception of methionine and valine and was similar to CP mean. The mean AME and TMEn values of FPS were estimated equal to 10.8 and 11.0 MJ ME/kg, respectively.展开更多
This study was carried out to evaluate the effects of graded levels of fiber from rice hull and the caecectomy on metabolizable energy（ME） and amino acid digestibility（AAD） in 42 Wuzong geese（21 intact and 21 cae...This study was carried out to evaluate the effects of graded levels of fiber from rice hull and the caecectomy on metabolizable energy（ME） and amino acid digestibility（AAD） in 42 Wuzong geese（21 intact and 21 caecectomized）. The experiment was a 3×2 factorial randomized design with 3 fiber levels and 2 treatments of geese（caecectomized and intact）. Each of the 3 diets was tube-fed（60 g） to 7 caecectomized and 7 intact adult Wuzong geese that had been fasted for 24 h. Excreta were collected for the next 48 h. The same geese were also fasted for estimation of endogenous losses of amino acids（AA） and energy after short period recovery. AA content and metabolizable energy value were determined in the excreta. In general, significant effects were found for fiber levels on apparent digestibility of Thr, Leu, Pro, Glu,Val, Ala and total AA（P〈0.05）. Apparent metabolizable energy（AME） and true metabolizable energy（TME） were both significantly influenced by increased fiber levels（P〈0.01）. Compared with caecectomized geese, markedly increases of AME and TME were found in intact geese（P〈0.01 for AME and P 〈0.05 for TME）, but no difference in the AAD were found between intact and caecectomized geese（P〉0.05）, except for Lys and Try（P〈0.05）. These observations suggested that dietary fiber level played an important role in digestibility of AAD and ME. Intact geese should be chosen for the nutrient evaluation of feedstuffs in practice, resulting from the significant difference between caecectomized and intact geese.展开更多
Two experiments were conducted to study the accuracy of predicting true metabolizable energy(TME)of ingredients for ducks from in vitro digestible energy(IVDE)determined with a computer-controlled simulated digestion ...Two experiments were conducted to study the accuracy of predicting true metabolizable energy(TME)of ingredients for ducks from in vitro digestible energy(IVDE)determined with a computer-controlled simulated digestion system.Experiment 1 was to establish TME prediction models from the IVDE of 9 energy feed ingredients and 12 protein feed ingredients using regression analysis.Experiment 2 was to validate the accuracy of the predicted ME of 10 ingredients randomly selected from Exp.1.Ten diets were formulated with 2 to 6 of 10 ingredients.Dietary in vivo TME values were compared with calculated values based on the TME predicted in Exp.1.In Exp.1,the correlation coefficients between TME and IVDE were 0.9339(P<0.05)in 9 energy feed ingredients and 0.8332(P<0.05)in 12 protein feed ingredients.No significant difference was observed on the slope and intercept of TME regression models between 9 energy feed ingredients and 12 protein feed ingredients.Therefore,the regression model of TME on IVDE for 21 feed ingredients was TME=0.7169×IVDE+1,224(R^(2)=0.7542,P<0.01).Determined and predicted TME differed by less than 100 kcal/kg of DM in 11 ingredients,and the difference ranged from 100 to 200 kcal/kg of DM in 5 ingredients.However,the difference between determined and predicted TME varied from 410 to 625 kcal/kg of DM in rice bran,rapeseed meal,corn gluten meal,and citric acid meal.In Exp.2,the determined and calculated TME were comparable(3,631 vs.3,639 kcal/kg of DM)and highly correlated(r=0.9014;P<0.05)in 10 diets.Determined and calculated TME differed by less than 100 kcal/kg of DM in 7 diets and by 106 to 133 kcal/kg of DM in 3 diets.These results have demonstrated that TME can be accurately predicted from IVDE in most feed ingredients,but it is less accurate for rice bran,rapeseed meal,corn gluten and citric acid meal.展开更多
The objective of this experimentwas to develop a new computer-controlled simulated digestion system to predict the digestible energy(DE)and metabolizable energy(ME)of unconventional plant protein meals for growing pig...The objective of this experimentwas to develop a new computer-controlled simulated digestion system to predict the digestible energy(DE)and metabolizable energy(ME)of unconventional plant protein meals for growing pigs.Nine meals tested included 1 source of rapeseed meal,4 sources of cottonseed meal,2 sources of sunflower meal,and 2 sources of peanut meal.Twenty growing pigs(Duroc[LandraceLarge White])with an initial body weight(BW)of 41.7±2.6 kg were allotted to a replicated 103 incomplete Latin square design to determine the DE and ME of 1 basal diet and 9 experimental diets formulated with 9 unconventional plant protein meals.The DE andMEvalues of unconventional plant protein meals were calculated by the difference method.The in vitro digestible energy(IVDE)of 1 basal diet,9 experimental diets,and 9 unconventional plant protein meals were determined with 5 replicates of each sample in a complete randomized arrangement.The IVDE/DE or IVDE/ME ranged from 0.96 to 0.98 or 1.00 to 1.01,and the correlation coefficient between IVDE and DE or MEwas 0.97 or 0.98 in 10 experimental diets.Accordingly,the IVDE/DE or IVDE/ME ranged from 0.86 to 1.05 or 0.96 to 1.20,and the correlation coefficient between IVDE and DE orME was 0.92 or 0.91 in 9 unconventional plant protein meals.The coefficient of variation(CV)of IVDE was less than that of DE and ME in the experimental diets(0.43%,0.80%,and 0.97%for CV of IVDE,DE and ME,respectively)and unconventional plant protein meals(0.92%,4.84%,and 6.33%for CV of IVDE,DE and ME,respectively).The regression equations to predict DE from IVDE in 10 experimental diets and 9 unconventional plant protein meals were DE=0.8851IVDE t539(R^(2)=0.9411,residual standard deviation[RSD]=23 kcal/kg DM,P<0.01)and DE=0.9880IVDE t 166(R^(2)=0.8428,RSD=182 kcal/kg DM,P<0.01),respectively.Therewas no statistical difference in the slopes(P=0.82)or intercepts(P=1.00)of these 2 equations.Thus,10 diets and 9 unconventional plant protein meals were pooled to establish the regression equation of DE on IVDE as:DE=0.9813IVDE t187(R^(2)=0.9120,RSD=118 kcal/kg DM,P<0.01).The regression equations to predictME from IVDE in 10 experimental diets and 9 unconventional plant protein meals were ME=0.9559IVDE t146(R^(2)=0.9697,RSD=18 kcal/kg DM,P<0.01)and ME=0.9388IVDEt3(R^(2)=0.8282,RSD=182 kcal/kg DM,P<0.01),respectively.Therewas no statistical difference in slopes(P=0.97)but significant difference between the intercepts(P=0.02)of these 2 equations.Our results indicate IVDE has similar response to the DE but different response to the ME in 10 experimental diets and 9 unconventional plant protein meals.Therefore,IVDE is moresuitable to predict DE than ME of diets and unconventional plant protein meals for growing pigs.展开更多
The objectives of this study were to determine: 1) the effects of konjac flour residues and ramie on digestible energy(DE), metabolizable energy(ME) and apparent total tract digestibility(ATTD) of nutrients in diets f...The objectives of this study were to determine: 1) the effects of konjac flour residues and ramie on digestible energy(DE), metabolizable energy(ME) and apparent total tract digestibility(ATTD) of nutrients in diets fed to growing pigs, 2) the DE and ME contents of konjac flour residues and ramie.Thirty barrows were allotted to 1 of 5 treatments with 6 replicates per treatment.The 5 diets include a corn-soybean meal basal diet(CTL), konjac flour residues diets containing 15% konjac flour residues(LK)or 30% konjac flour residues(HK), and ramie diets containing 15% ramie(LR) or 30% ramie(HR).The experiment lasted 19 days, including 7 days for cage adaptation, 7 days for diet adaptation, and 5 days for total feces and urine collection.The energy values and ATTD of nutrients in each diet were determined,and DE and ME contents of konjac flour residues and ramie were calculated.The results showed that consumption of konjac flour residues significantly increased(P < 0.01) the fecal moisture content compared with the ramie treatment.The LK, HK and HR diets had lower(P < 0.01) DE values compared with the CTL diet.The HR diet had greater(P < 0.01) DE value compared with the HK diet.The LK and LR diets showed greater(P < 0.01) ATTD of DM, OM, GE and CP compared with the HK and HR diets.The HK diet had the lowest(P < 0.01) ATTD of ether extract(EE) among the 5 diets.No differences were observed for the ATTD of NDF and ADF among the 5 diets.Moreover, the DE and ME values of konjac flour residues under 2 inclusion levels(15% and 30%) were 11.66, 11.87 MJ/kg and 10.41, 10.03 MJ/kg, respectively.The corresponding values for ramie were 13.27, 13.16 MJ/kg and 13.07, 12.82 MJ/kg, respectively.In conclusion, the differences in fecal moisture content and the ATTD of EE among the 5 diets were mainly due to the different chemical compositions of konjac flour residues and ramie.Compared with konjac flour residues, ramie has greater DE and ME values under the same inclusion level.展开更多
Optimizing the energy utilization of nutrients and ensuring maximum benefits are continuous goals for livestock producers.The net energy(NE)value of feed reflects its nutritional value in the precision feeding system....Optimizing the energy utilization of nutrients and ensuring maximum benefits are continuous goals for livestock producers.The net energy(NE)value of feed reflects its nutritional value in the precision feeding system.An experiment was conducted to determine the apparent metabolizable energy(AME)and NE values of 3 types of dephenolized cottonseed protein(DCP)for Hy Line Brown hens aged 42 to 45 weeks using the reference diet substitution method.A reference diet based on corn soybean meal was used to meet the nutritional needs of Hy Line Brown laying hens.To render the crude protein and energy values of the 3 test diets similar,10.5%,12%,and 16%of the gross energy yielding ingredients from the reference diet were replaced with DCP 1,DCP 2,and DCP 3,respectively.The birds were fed 4 diets during a 7-d adaptation period.After the dietary adaptation period,2 birds per replicate from each treatment group were placed in an individual open circuit respiratory calorimetry chamber for a 3-d experimental period.Daily O_(2)consumption and CO_(2)production were recorded,and excreta samples were collected.The AME values of DCP 1,DCP 2,and DCP 3 were 3,049.05,2,820.13,and 2,982.31 kcal/kg of dry matter(DM),respectively.The NE values of DCP 1,DCP 2,DCP 3 were 1,475.77,1,910.31,and 1,905.37 kcal/kg of DM,respectively,and the NE:AME ratios were 48.40%,67.74%,and 63.89%,respectively.Our data show that the AME value of DCP does not reflect the nutritional value of the feed.The NE value of DCP with a high ME value was not necessarily high.展开更多
The present study was conducted to test whether the dietary supplementation of β-mannanase affects amino acids(AA) digestibility,metabolizable energy(ME) contents of corn,wheat,soybean meal,distillers dried grains wi...The present study was conducted to test whether the dietary supplementation of β-mannanase affects amino acids(AA) digestibility,metabolizable energy(ME) contents of corn,wheat,soybean meal,distillers dried grains with solubles,and palm kernel meal(PKM),nutrient digestibility,and growth performance of pigs.In Exp.1,22 cannulated pigs were used for 10 dietary treatments including 5 feed ingredients and 2 β-mannanase concentrations(0 and 0.5 g/kg of the diet) in 6 periods in an incomplete Latin square design to determine the AA and energy digestibility.In Exp.2,200 growing pigs were randomly allotted to 4 treatments with 2 nutrient levels(high and low) and 2 concentrations of β-mannanase(2×2 factorial arrangement) in 2 phases(phase 1,d 0 to 21;and phase 2,d 22 to 42).In Exp.1,β-mannanase increased the mean standardized ileal digestibility(SID) of AA in all feed ingredients.The amount of digestible energy was increased(P <0.05) in β-mannanase-treated PKM.Pigs fed β-mannanase showed a greater(P <0.05) digestibility of gross energy(GE).The feed-to-gain(F:G) ratio was improved(P <0.01) in pigs fed high-nutrient diets.Pigs fed β-mannanase in the diets had greater(P <0.05) average daily gain and F:G.In phase 2,the concentration of fecal ammonia was decreased(P <0.05) in pigs fed β-mannanase.Considering the 2 experiments,it can be concluded that β-mannanase increases the SID of AA,which has to be considered in balancing the rations.展开更多
Currently,specific nutrient concentration,metabolizable energy(ME)and digestible amino acids are used as feed formulation criteria.A balanced nutrient density(BND)concept based on 2 criteria of nutrient density and ba...Currently,specific nutrient concentration,metabolizable energy(ME)and digestible amino acids are used as feed formulation criteria.A balanced nutrient density(BND)concept based on 2 criteria of nutrient density and balanced amino acids-to-ME ratio may offer more flexibility in optimisation of profit in formulation of diets compared with current formulation based on set values per unit of feed mass.A total of 672 one-d-old off-sex male Ross 308 broiler chickens were used across two 42-d performance trials in a 3×2 factorial arrangement of treatments with each diet replicated 8 times(14 birds per replicate).The experimental factors were 2 nutrient density levels(low[LD]and high[HD])and 3 digestible lysine-to-ME ratios(DLYS:ME;low,medium,and high).Low density diets had ME of 2,876 and 3,023 kcal/kg for starter and finisher,respectively,while values for HD diets were 3,169 and 3,315 kcal/kg with proportionally higher non-nitrogenated nutrients.Separate digestibility and apparent metaboliz-able energy(AME)assays were conducted at d 21 and 42.Digestibility assays at d 7 were conducted on birds used for performance trials.Regardless of the diet density,birds fed low DLYS:ME had a lower(P<0.01)feed intake(d 0 to 42)than medium and high DLYS:ME.Without interaction,birds fed low and medium DLYS:ME had a similar body weight gain being the heaviest while birds low DLYS:ME were the lightest.By an interaction(P<0.05),the highest overall FCR value was observed for birds fed LD×low DLYS:ME and improved linearly when DLYS:ME increased to the highest level reaching a limit for birds fed HD×medium DLYS:ME.Calorie conversion linearly decreased(P<0.001)with increments in DLYS:ME.Jejunal and ileal starch and protein digestibility were affected on d 21 and 42 but not on d 7 of age.Given the independence of response on BW and feed consumption,the use of BND as a flexible system in diet formulations has the potential to enable more accurate formulation for optimisation of growth performance of broiler chickens.展开更多
A comparative slaughter trial and a metabolism trial were conducted to determine the requirement of net energy （NE） and metabolizable energy （ME） by the crossbreed of German Mutton Merino×Inner Mongolia Merin...A comparative slaughter trial and a metabolism trial were conducted to determine the requirement of net energy （NE） and metabolizable energy （ME） by the crossbreed of German Mutton Merino×Inner Mongolia Merino for fattening from 35 to 50 kg of body weight （BW）. 49 crossbred female lambs （（33.9＋2.3） （SD） kg BW） of German Mutton Merino×lnner Mongolia Merino were used. 34 lambs were randomly chosen for comparative slaughter, which were offered an identical mixture diet （concentrate：roughage=55：45） at 100, 75 or 55% of ad libitum intake, whereas the remainders were used in the metabolism trial to evaluate the ME of the diet after methane production was measured by open-circuit respirometry. As feed intake decreased from 100 to 75 and 55% of ad libitum intake, the apparent digestibility of dry matter （DM） linearly increased （P=-0.010） from 60.8 to 63.6 and 66.9%, respectively, and methane production decreased from 52.1 to 44.3 and 39.9 L d-l, respectively, but the ratio of methane energy to gross energy intake increased linearly （P=0.010） from 8.20 to 8.96 and 10.97%, respectively. Consequently, the ME values of the diet increased from 9.35 to 9.64 and 9.85 MJ kg-~ DM, respectively. The NE requirement for maintenance （NEro） was 255 kJ kg-1 BW0.75, and the ME requirement for maintenance （MEre） was 352 kJ kg-I BW~.75, with a partial energy efficiency for maintenance （km） of 0.72. The NE requirement for growth （NEg） ranged from 1.26 to 4.66 MJ d-1as average daily gains increased from 100 to 300 g d-1, with a partial energy efficiency for growth （ks） of 0.45. These results indicated that the NEg required by crossbred female lambs of German Mutton Merinoxlnner Mongolia Merino was lower than the recommendation of the American or British nutritional system.展开更多
基金financially supported by China Agriculture Research System of MOF and MARA(CARS-41)the National Key R&D Project(2021YFD1300404)+2 种基金the Natural Science Foundation from Guangdong Province(2022A1515012069)the Science and Technology Plan Project of Guangzhou(SL2022A04J00940,2024E04J0562)the Science and Technology Program of Guangdong Academy of Agricultural Sciences(R2023PY-QY012,R2021YJ-YB3012),P.R.China。
文摘Background Dietary lysine and apparent nitrogen-corrected metabolizable energy(AMEn)are two key variables affecting the production of bre eder hens.In this study,the effe cts and interactions of lysine and AMEn on yellowfeathered broiler breeder hens were investigated.A total of 72030-week-old breeder hens were fed in a 5(lysine:0.56%,0,68%,0.80%,0,92%,and 1.04%)×2(AMEn:11.50 and 11.10 MJ/kg)factorial arrangement for 12 weeks.The productive performance,reproductive traits,biochemical variables of breeder hense the amino acid concentration and quality of eggs,and the growth performance of offspring broilers were determined.Result(1)Dietary lysine had quadratic effects(P<0.05)on laying rate,average daily egg mass and feed intake/egg mass of breeder hens;birds with 11.50 MJ/kg AMEn(high AMEn)had higher(P<0.05)BW than those with 11.10MJ/kg AMEn(low AMEn);(2)dietary lysine significantly affected on the relative ovarian weight(quadratic and linear),and numbers of large yellow follicles(LYF,quadratic);birds with high AMEn had longer fallopian tube and more LYF than those with low AMEn(P<0.05);(3)dietary lysine had significant effects(linear and quadratic)on eggshell thickness and shell strength of eggs from breeder hens;birds with high AMEn had thinner eggshells and deeper yolk color than those with low AMEn(P<0.05);(4)there were higher(P<0.05)contents of protein and concentrations of all measured animo acids(AAs)in eggs from birds fed low AMEn;(5)supplementation with high AMEn to breeder hens significantly increased the hatchability of fertilized eggs;(6)neither dietary lysine level or AMEn afofected growth performance of offspring broilers;(7)both dietary lysine level and AMEn significantly affected gonadotropin concentrations and biochemical variables of breeder hens.Conclusions Dietary lysine had significant influences on productive performance,reproductive traits,and egg quality of yellow-feathered breeder hens.Based on productive performance,the optimal levels of dietary lysine were 0.81%to 0.83%,while 0.71%to 72%lysine was enough to obtain the best quality of breeding eggs.High AMEn was more beneficial to breeder hens for reproductive traits and hatchability of the fertilized eggs,while it showed detrimental epfrfects on eggshell thickness and AA concentrations of breeding eggs.
基金supported by the University of Turin(Ex 60% 2014–2015)
文摘Background: The study aimed to determine the apparent total tract digestibility coefficients(ATTDC) of nutrients, the apparent metabolizable energy(AME and AMEn) and the amino acid(AA) apparent ileal digestibility coefficients(AIDC)of a partially defatted(BSFp) and a highly defatted(BSFh) black soldier fly larvae meal. The experimental diets were: a basal diet and two diets prepared by substituting 250 g/kg(w/w) of the basal diet with BSFp or BSFh, respectively.Results: Significant differences were found between BSFp and BSFh meals for ATTDC of the nutrients: BSFp resulted more digestible than BSFh, except for ATTDC of CP which did not differed between meals, while a statistical trend was observed for ATTDC of DM and EE. The AME and AMEn values were significantly(P < 0.05) different between the two BSF meals, with higher levels for BSFp(16.25 and 14.87 MJ/kg DM, respectively). The AIDC of the AA in BSFp ranged from 0.44 to 0.92, while in BSFh they ranged from 0.45 to 0.99. No significant differences were observed for the AA digestibility(0.77 and 0.80 for BSFp and BSFh, respectively), except for glutamic acid, proline and serine that were more digestible in the BSFh meal(P < 0.05).Conclusions: Defatted BSF meals can be considered as an excellent source of AME and digestible AA for broilers with a better efficient nutrient digestion. These considerations suggested the effective utilization of defatted BSF larvae meal in poultry feed formulation.
基金the Special Public Sector Fund in Agriculture(200903006)the State Key Laboratory of Animal Nutrition(2004DA125184-0810) of China+3 种基金National Natural Science Foundation of China(NSFC3080078931072040)Ministry of Science and Technology of the People's Republic of China(2006BAD12B05-102009IM03310005)
文摘A total of 335 lactating sows （Landrace x Large White） were used in two experiments to determine the optimum ratio of standardized ileal digestible lysine （SID-Lys） to metabolizable energy （ME） for mixed parity sows during lactation. In Exp. 1, 185 sows （weighing an average of 256.2 ± 6.5 kg and having an average parity of 3.4 ± 0.3） were allocated to one of six experimental diets in a completely randomized block design within parity groups （1, 2, and 3＋）. The experimental diets were formulated to contain 3.06, 3.16, 3.20, 3.25, 3.30 or 3.40 Mcal/kg of ME and each diet was fed to the sows throughout a 28 day lactation. All diets provided a similar SID-lysine level （0.86%）. As a result, the diets provided a SID-Lys：ME ratio of 2.81, 2.72, 2.69, 2.65, 2.61 or 2.53 g/Mcal ME. Sow feed intake was significantly （P 〈 0.01） affected by the energy content of the diet as well as by sow parity. Using regression analysis, feed intake was shown to be maximized at 3.25, 3.21, 3.21 and 3.21 Mcal/kg of ME for parity 1, 2, 3＋ sows and the entire cohort of sows respectively （quadratic; P 〈 0.01）. In addition, the result of feed intake can be expressed as 2.65, 2.69, 2.69 and 2.68 g/Mcal based on analysis of SID-Lys：ME ratio. Litter weight gain was affected by dietary treatment for parity 3＋ sows and the entire cohort （P 〈 0.01）. Based on regression analysis, litter weight gain was maximized at 3.25 and 3.24 Mcal/kg of ME for parity 3＋ （quadratic; P 〈 0.01） and the entire cohort （quadratic; P 〈 0.01）. Similarly, the result of litter weight gain could be expressed as 2.65 and 2.66 g/Mcal of SID- Lys：ME ratio. Therefore, 3.25 Mcal/kg of ME was selected for Exp. 2 in which 150 sows （weighing 254.6 ± 7.3 kg and having an average parity of 3.4 ± 0.4） were allocated to one of five treatments in a completely randomized block design within parity （1, 2, and 3＋）. The experimental diets were formulated to contain 2.1, 2.4, 2.7, 3.0 or 3.3 g/Mcal of SID-Lys：ME ratio with all diets providing 3.25 Mcal/kg of ME. The diets were fed to the sows throughout a 28 day lactation. Sow body weight loss was affected by dietary treatment （parity 3＋ sows, P = 0.02; entire cohort, P 〈 0.01） and by sow parity （P 〈 0.01）. Litter weight at weaning and litter weight gain were affected by dietary treatment for parity 1, 2, 3＋ sows and the entire cohort （P 〈 0.01） as well as by sow parity （P 〈 0.01）. Plasma urea nitrogen （P 〈 0.01）, creatinine （P 〈 0.01） and non-esterifide fatty acids （P = 0.04） were decreased as the SID-Lys：ME ratio of the diet increased. Insulin-like growth factor-1 （P = 0.02）, estradiol （P 〈 0.01） and luteinizing hormone （P = 0.02） were increased as the SID-Lys：ME ratio in diet increased. Based on a broken-line model, the estimated SID-Lys： ME ratio to maximize litter weight gain was estimated to be 3.05 g/Mcal.
基金supported by grants from the National Nonprofit Institute Research Grant (Y2020PT02)the earmarked fund for the modern agroindustry technology research system (CARS-41)+1 种基金Agricultural Science and Technology Innovation Program (ASTIP-IAS04ASTIP-IAS-TS-15)。
文摘Background: Improving the feed efficiency would increase profitability for producers while also reducing the environmental footprint of livestock production. This study was conducted to investigate the relationships among feed efficiency traits and metabolizable efficiency traits in 180 male broilers. Significant loci and genes affecting the metabolizable efficiency traits were explored with an imputation-based genome-wide association study. The traits measured or calculated comprised three growth traits, five feed efficiency related traits, and nine metabolizable efficiency traits.Results: The residual feed intake(RFI) showed moderate to high and positive phenotypic correlations with eight other traits measured, including average daily feed intake(ADFI), dry excreta weight(DEW), gross energy excretion(GEE), crude protein excretion(CPE), metabolizable dry matter(MDM), nitrogen corrected apparent metabolizable energy(AMEn), abdominal fat weight(Ab F), and percentage of abdominal fat(Ab P). Greater correlations were observed between growth traits and the feed conversion ratio(FCR) than RFI. In addition, the RFI, FCR, ADFI, DEW,GEE, CPE, MDM, AMEn, Ab F, and Ab P were lower in low-RFI birds than high-RFI birds(P < 0.01 or P < 0.05), whereas the coefficients of MDM and MCP of low-RFI birds were greater than those of high-RFI birds(P < 0.01). Five narrow QTLs for metabolizable efficiency traits were detected, including one 82.46-kb region for DEW and GEE on Gallus gallus chromosome(GGA) 26, one 120.13-kb region for MDM and AMEn on GGA1, one 691.25-kb region for the coefficients of MDM and AMEn on GGA5, one region for the coefficients of MDM and MCP on GGA2(103.45–103.53 Mb), and one 690.50-kb region for the coefficient of MCP on GGA14. Linkage disequilibrium(LD) analysis indicated that the five regions contained high LD blocks, as well as the genes chromosome 26 C6 orf106 homolog(C26 H6 orf106), LOC396098, SH3 and multiple ankyrin repeat domains 2(SHANK2), ETS homologous factor(EHF), and histamine receptor H3-like(HRH3 L), which are known to be involved in the regulation of neurodevelopment, cell proliferation and differentiation, and food intake.Conclusions: Selection for low RFI significantly decreased chicken feed intake, excreta output, and abdominal fat deposition, and increased nutrient digestibility without changing the weight gain. Five novel QTL regions involved in the control of metabolizable efficiency in chickens were identified. These results, combined through nutritional and genetic approaches, should facilitate novel insights into improving feed efficiency in poultry and other species.
基金financially supported by the National Key Technology R & D Program in the 11th Five Year Plan of China(2006BAD12B01)Special Public Sector Fund in Agriculture(200903006)
文摘Background： The nutrient composition of corn is variable. To prevent unforeseen reductions in growth performance, grading and analytical methods are used to minimize nutrient variability between calculated and analyzed values. This experiment was carried out to define the sources of variation in the energy content of corn and to develop a practical method to accurately estimate the digestible energy （DE） and metabolisable energy （ME） content of individual corn samples for growing pigs. Twenty samples were taken from each of five provinces in China （Jilin, Hebei, Shandong, Liaoning, and Henan） to obtain a range of quality. Results： The DE and ME contents of the 100 corn samples were measured in 3.5.3 ±1.92 kg growing pigs （six pigs per corn sample）. Sixty corn samples were used to build the prediction model; the remaining forty samples were used to test the suitability of these models. The chemical composition of each corn sample was determined, and the results were used to establish prediction equations for DE or ME content from chemical characteristics. The mean DE and ME content of the 100 samples were 4,053 and 3,923 kcal/kg （dry matter basis）, respectively. The physical characteristics were determined, as well, and the results indicated that the bulk weight and 1,000-kernel weight were not associated with energy content. The DE and ME values could be accurately predicted from chemical characteristics. The best fit equations were as follows： DE, kcal/kg of DM = 1062.68 ＋ （49.72 ×EE） ＋ （0.54 × GE） ＋ （9.1 ] x starch）, with R^2 = 0.62, residual standard deviation （RSD） = 48 kcal/kg, and P 〈 0.01; ME, kcal/kg of dry matter basis （DM） = 671.54 ＋ （0.89 ×DE） - （5.57 × NDF） - （191.39 ×ash）, with R^2 = 0.87, RSD = 18 kcal/kg, and P〈 0.01. Conclusion： This experiment confirms the large variation in the energy content of corn, describes the factors that influence this variation, and presents equations based on chemical measurements that may be used to predict the DE and ME content of individual corn samples.
基金supported by the State Key Laboratory of Animal Nutrition (2004DA125184-0810) of ChinaNational Natural Science Foundation of China(31072040)+2 种基金Guangdong cooperation project between Industry-Academia-Research of China (2009B090300110)the Ministry of Science and Technology of the People's Republic of China(2006BAD12B05-10Nyhyzx07-34)
文摘A total of 2,121 growing-finishing pigs （Duroc × Landrace ×Large White） were utilized in six experiments conducted to determine the effects of different ratios of standardized ileal digestible lysine （SID-Lys） to metabolizable energy （ME） on the performance and carcass characteristics of growing-finishing pigs. Exps. 1 （30 to 50 kg）, 2 （52 to 70 kg） and 3 （81 to 104 kg） were conducted to find an optimum ME level and then this level was used in Exps. 4 （29 to 47 kg）, 5 （54 to 76 kg） and 6 （84 to 109 kg） to test the response of pigs to different ratios of SID-Lys：ME. In Exps.1 to 3, four treatments were used consisting of diets with a formulated ME content of 3.1, 3.2, 3.3 or 3.4 in Exps. I and 2 while Exp. 3 used 3.05, 3.1 S, 3.25 or 3.35 Mcal/kg. A constant SID-Lys：ME ratio of 2.6, 2.3 or 2.0 g/Mcal was used in Exps. 1, 2 and 3, respectively. Weight gain was significantly increased with increasing energy level in Exp.1 while weight gain was unaltered in Exps. 2 and 3. For all three experiments, feed intake was decreased （P 〈 0.05） and feed efficiency was improved （P 〈 0.05） with increasing energy level. Tenth rib back fat thickness linearly increased （P 〈 0.05） with increasing energy level, in Exps. 4 to 6, five treatments were used consisting of diets with a SID-Lys：ME ratio of 2.4, 2.6, 2.8, 3.0 or 3.2 in Exp. 1, 2.1, 2.3, 2.5, 2.7, 2.9 or 3.2 in Exp. 2 and 1.8, 2.0, 2.2, 2.4, or 2.6 in Exp. 3. A constant ME level 3.2, 3.2 and 3.05 Mcal/kg was used in Exps. 1, 2 and 3, respectively （selected based on the results of weight gain）. For all three experiments, weight gain increased （P 〈 0.05） and feed efficiency improved linearly （P 〈 0.05） as the SID-Lys：ME ratio increased. Tenth rib back fat thickness linearly decreased （P 〈 0.0,5） as the SID-Lys：ME ratio increased. Based on a straight broken-line model, the estimated SID-Lys：ME ratio to maximize weight gain was 3.0, 2.43 and 2.2 for 29 to 47, 54 to76 and 84 to 109 kg of pigs, respectively.
基金financed by China Agriculture Research System(CARS-41K15)Fund for Agro-scientific Research in the Public Interest (FARA200903006-01)China Agriculture Research System-Beijing Team for Poultry Industry
文摘Background： This study was conducted to evaluate the apparent metabolizable energy （AME） and true metabolizable energy （TME） contents in 30 sources of corn distillers dried grains with solubles （DDGS） in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical composition and color score. Methods： Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy （ME） contents, measured for color score and chemical composition （crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber）, to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed （50 g） to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses. Results： Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content （-0.64, P 〈 0.0]） and between ME and yellowness score （0.39, P 〈 0.05） of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME = 6.57111 ＋ 0.5]475 GE - 0.10003 NDF ＋ 0.1 3380 ADF ＋ 0.07057 fat - 0.57029 ash - 0.02437 L （R^2 = 0.70）. The best-fit regression equation for TME content of DDGS was TME = 7.92283 ＋ 0.51475 GE - 0.10003 NDF ＋ 0.13380 ADF ＋ 0.07057 fat - 0.57029 ash - 0.02437 L （R2 = 0.70）. Conclusions： This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.
基金financially supported by China Special Public Sector Fund in Agriculture(200903006)The collection of data and analysis were funded by National Key Technology Research and Development Program(2011BAD26B0404)The interpretation of data and writing of the manuscript were supported by 111 Project(B16044)
文摘Background： The ability of near-infrared reflectance spectroscopy（NIRS） to determine the digestible energy（DE）and metabolizable energy（ME） content of corn fed to growing pigs was tested. One hundred and seventeen corn samples, comprising different planting regions and varieties were collected from all over China in a three-year period. The samples were randomly split into a calibration set（n = 88） and a validation set（n = 29）. The actual and calculated DE and ME content of the corn samples was determined by digestion-metabolism experiments and the prediction equations of Noblet and Perez（J Anim Sci. 71：3389–98,1993）. The samples were then subjected to NIRS scanning and calibrations were performed by the modified partial least square（MPLS） regression method based on77 different spectral pre-treatments. The NIRS equations based on the actually determined and calculated DE and ME were built separately and then validated using validation samples.Results： The NIRS equations obtained from actually determined DE, the coefficient of determination for calibration（RSQcal）, cross-validation（R^2CV）, and validation（RSQv） were 0.89, 0.87 and 0.86, and these values for determined ME were 0.87, 0.86 and 0.86. For the NIRS equations built from calculated DE, the RSQcal, R^2CV, and RSQvvalues were 0.88, 0.85 and 0.84, and these values for calculated ME were 0.86, 0.84 and 0.82. Except for the equation based on calculated ME（RPD_v= 2.38, 〈 2.50）, the other three equations built from actually determined energy and calculated DE produced good prediction performance（RPD_vranging from 2.53 to 2.69, 〉 2.50） when applied to validation samples.Conclusion： These results indicate that NIRS can be used as a quantitative method for the rapid determination of the available energy in corn fed to growing pigs, and the NIRS equations based on the actually determined energy produced better predictive performance than those built from calculated energy values.
基金supported by the earmarked fund for the China Agriculture Research System(CARS-39)
文摘Background： Dorper is an important breed for meat purpose and widely used in the livestock industry of the world.However, the protein requirement of Dorper crossbred has not been investigated. The current paper reports the net protein（NP） and metabolizable protein（MP） requirements of Dorper crossbred ram lambs from 20 to 35 kg BW.Methods： Thirty-five Dorper × thin-tailed Han crossbred lambs weaned at approximately 50 d of age（20.3 ± 2.15 kg of BW） were used. Seven lambs of 25 kg BW were slaughtered as the baseline animals at the start of the trial. An intermediate group of seven randomly selected lambs fed ad libitum was slaughtered at 28.6 kg BW. The remaining 21 lambs were randomly divided into three levels of dry matter intake： ad libitum or 70% or 40% of ad libitum intake. Those lambs were slaughtered when the lambs fed ad libitum reached 35 kg BW. Total body N and N retention were measured.Results： The daily NP and MP requirements for maintenance were 1.89 and 4.52 g/kg metabolic shrunk BW（SBW0.75）.The partial efficiency of MP utilization for maintenance was 0.42. The NP requirement for growth ranged from 12.1 to 43.5 g/d, for the lambs gaining 100 to 350 g/d, and the partial efficiency of MP utilization for growth was 0.86.Conclusions： The NP and MP requirements for the maintenance and growth of Dorper crossbred male lambs were lower than the recommendations of American and British nutritional systems.
基金support received from the State Key Laboratory of Animal Nutrition of China ( No .2004DA125184-0810)National Natural Science Foundation of China(No .31072040)+1 种基金Guangdong Cooperation Project be-tween Industry-Academia-Research of China ( No .2009B090300110)the Ministry of Science and Technology of the People’s Republic of China ( No .2006BAD12B05-10and No . Nyhyzx07-34)
文摘A total of 480 nursery pigs （Duroc x Landrace x Large White） were utilized in two experiments conducted to determine the effects of different ratios of standardized ileal digestible lysine （SID- Lys） to metabolizable energy （ME） ratio on the performance, nutrient digestibility, plasma urea nitrogen （PUN） ,and plasma free amino acids of 10 to 28 kg pigs. In Exp. 1, 192 pigs （ 10.58 kg） were assigned to one of four treatments. The treatments consisted of diets with a ME content of 3.2, 3.25, 3.3, or 3.35 Mcal/kg with a constant SID-Lys：ME ratio of 3.7 g/Mcal. The experiment lasted 28 days. Pigs which were fed the diets containing 3.3 and 3.35 Mcal/kg ME had lower feed intakes （ P 〈 0.05）than those fed 3.2 Mcal/kg. Feed efficiency was linearly improved with increasing dietary ME （ P 〈0.05）. Increasing the dietary ME level also increased （P 〈0.05 ） dry matter and energy digestibility. Therefore,3.3 Mcal/kg ME was selected for Exp. 2 in which 288 pigs （ 10.60 kg） were assigned to one of six treatments. Treatments consisted of SID-Lys： ME ratios of 3.1,3.3,3.5,3.7,3.9, or 4.1 g/Mcal with all diets providing 3.3 Mcal of ME/kg. Weight gain and feed efficiency were increased （P 〈0.05 ） as the SID-Lys：ME ratio in diet increased. Based on a straight broken-line model ,the estimated SID-Lys：ME ratio to maximize weight gain was 3.74.
基金funded by the Education Department Production and Research Program of Guangdong Province ( 2009B090300088)
文摘[ Objective] To investigate the effects of different levels of metabolizable energy and crude protein on egg laying performance and hatch- ing efficiency in Magang geese. [Method] The healthy Magang geese at 2 years old were randomly assigned into four groups, group Ⅰ, group Ⅱ, group Ⅲ and control group. They were fed with diets at different levels of metabolizable energy and crude protein, and then their eggs were collect- ed and hatched. During the test, their health was observed, and the egg weight, egg yield and hatching rate were recorded. [ Result] The average egg laying rates and average egg weight were significantly higher in the group Ⅰ, group Ⅱ and group Ⅲ than in the control group. The hatchable egg rates and egg fertilization rates of the group Ⅰ, group Ⅱ and group Ⅲ were also increased, and significance was found between the group Ⅲ and the other group （P 〈 0.05）. The feed costs of the three test groups were lower than that of the control group, and the feed cost was higher in the group Ⅲ than that in the group Ⅰ and Ⅱ. [ Conclusion] The levels of metabolizable energy and crude protein in diet have significant effects on laying performance and hatching efficiency in Magang geese.
文摘The aim of this study was to determine the apparent （AME） ＆ true （TMEn） metabolizable energy as well as the crude protein （CP） ＆ amino acid （AA） total tract （by excreta collection） digestibility （bioavailability） of field pea seeds （FPS） of the Greek cultivar ＂Olympos＂. Forty eight broilers were placed in individual cages and randomly allocated into 4 dietary treatments. Birds consumed 80 g/d of either a typical commercial diet or the same diet in which 100, 200 or 300 g/kg had been substituted by ground FPS. The experiment lasted 15 d. Apparent and true CP bioavailability of FPS were significantly decreased （P 〈 0.05） only at the inclusion rate of 300 g/kg. AA bioavailability remained at high levels （-0.80）, with the exception of methionine and valine and was similar to CP mean. The mean AME and TMEn values of FPS were estimated equal to 10.8 and 11.0 MJ ME/kg, respectively.
基金sponsored by the China Agriculture Research System (CARS-43-14)the Special Fund for Agro-Scientific Research in the Public Interest, China (201303143)+1 种基金the Open Research Fund Projects of the State Key Laboratory of Animal Nutrition, China (2004DA125184F1308)the Ministry of Education Doctoral Joint Funds of the New Teacher, China (20134404120024)
文摘This study was carried out to evaluate the effects of graded levels of fiber from rice hull and the caecectomy on metabolizable energy（ME） and amino acid digestibility（AAD） in 42 Wuzong geese（21 intact and 21 caecectomized）. The experiment was a 3×2 factorial randomized design with 3 fiber levels and 2 treatments of geese（caecectomized and intact）. Each of the 3 diets was tube-fed（60 g） to 7 caecectomized and 7 intact adult Wuzong geese that had been fasted for 24 h. Excreta were collected for the next 48 h. The same geese were also fasted for estimation of endogenous losses of amino acids（AA） and energy after short period recovery. AA content and metabolizable energy value were determined in the excreta. In general, significant effects were found for fiber levels on apparent digestibility of Thr, Leu, Pro, Glu,Val, Ala and total AA（P〈0.05）. Apparent metabolizable energy（AME） and true metabolizable energy（TME） were both significantly influenced by increased fiber levels（P〈0.01）. Compared with caecectomized geese, markedly increases of AME and TME were found in intact geese（P〈0.01 for AME and P 〈0.05 for TME）, but no difference in the AAD were found between intact and caecectomized geese（P〉0.05）, except for Lys and Try（P〈0.05）. These observations suggested that dietary fiber level played an important role in digestibility of AAD and ME. Intact geese should be chosen for the nutrient evaluation of feedstuffs in practice, resulting from the significant difference between caecectomized and intact geese.
基金This work was financially supported by the Innovation Team of the Chinese Academy of Agricultural Sciences(ASTIP-IAS07)(Beijing,China)and fund of Newhope Liuhe Co.,Ltd.(2014-YF-01)(Beijing,China).
文摘Two experiments were conducted to study the accuracy of predicting true metabolizable energy(TME)of ingredients for ducks from in vitro digestible energy(IVDE)determined with a computer-controlled simulated digestion system.Experiment 1 was to establish TME prediction models from the IVDE of 9 energy feed ingredients and 12 protein feed ingredients using regression analysis.Experiment 2 was to validate the accuracy of the predicted ME of 10 ingredients randomly selected from Exp.1.Ten diets were formulated with 2 to 6 of 10 ingredients.Dietary in vivo TME values were compared with calculated values based on the TME predicted in Exp.1.In Exp.1,the correlation coefficients between TME and IVDE were 0.9339(P<0.05)in 9 energy feed ingredients and 0.8332(P<0.05)in 12 protein feed ingredients.No significant difference was observed on the slope and intercept of TME regression models between 9 energy feed ingredients and 12 protein feed ingredients.Therefore,the regression model of TME on IVDE for 21 feed ingredients was TME=0.7169×IVDE+1,224(R^(2)=0.7542,P<0.01).Determined and predicted TME differed by less than 100 kcal/kg of DM in 11 ingredients,and the difference ranged from 100 to 200 kcal/kg of DM in 5 ingredients.However,the difference between determined and predicted TME varied from 410 to 625 kcal/kg of DM in rice bran,rapeseed meal,corn gluten meal,and citric acid meal.In Exp.2,the determined and calculated TME were comparable(3,631 vs.3,639 kcal/kg of DM)and highly correlated(r=0.9014;P<0.05)in 10 diets.Determined and calculated TME differed by less than 100 kcal/kg of DM in 7 diets and by 106 to 133 kcal/kg of DM in 3 diets.These results have demonstrated that TME can be accurately predicted from IVDE in most feed ingredients,but it is less accurate for rice bran,rapeseed meal,corn gluten and citric acid meal.
基金theCentral Public-Interest Scientific Institution Basal Research Fund(No.2021-YWF-ZYSQ-09)the Agricultural Science and Technology Innovation Program,Chinese Academy of Agricultural Sciences(ASTIP-IAS07)Wen’s Food Group Co.Ltd(2018-YF-01).
文摘The objective of this experimentwas to develop a new computer-controlled simulated digestion system to predict the digestible energy(DE)and metabolizable energy(ME)of unconventional plant protein meals for growing pigs.Nine meals tested included 1 source of rapeseed meal,4 sources of cottonseed meal,2 sources of sunflower meal,and 2 sources of peanut meal.Twenty growing pigs(Duroc[LandraceLarge White])with an initial body weight(BW)of 41.7±2.6 kg were allotted to a replicated 103 incomplete Latin square design to determine the DE and ME of 1 basal diet and 9 experimental diets formulated with 9 unconventional plant protein meals.The DE andMEvalues of unconventional plant protein meals were calculated by the difference method.The in vitro digestible energy(IVDE)of 1 basal diet,9 experimental diets,and 9 unconventional plant protein meals were determined with 5 replicates of each sample in a complete randomized arrangement.The IVDE/DE or IVDE/ME ranged from 0.96 to 0.98 or 1.00 to 1.01,and the correlation coefficient between IVDE and DE or MEwas 0.97 or 0.98 in 10 experimental diets.Accordingly,the IVDE/DE or IVDE/ME ranged from 0.86 to 1.05 or 0.96 to 1.20,and the correlation coefficient between IVDE and DE orME was 0.92 or 0.91 in 9 unconventional plant protein meals.The coefficient of variation(CV)of IVDE was less than that of DE and ME in the experimental diets(0.43%,0.80%,and 0.97%for CV of IVDE,DE and ME,respectively)and unconventional plant protein meals(0.92%,4.84%,and 6.33%for CV of IVDE,DE and ME,respectively).The regression equations to predict DE from IVDE in 10 experimental diets and 9 unconventional plant protein meals were DE=0.8851IVDE t539(R^(2)=0.9411,residual standard deviation[RSD]=23 kcal/kg DM,P<0.01)and DE=0.9880IVDE t 166(R^(2)=0.8428,RSD=182 kcal/kg DM,P<0.01),respectively.Therewas no statistical difference in the slopes(P=0.82)or intercepts(P=1.00)of these 2 equations.Thus,10 diets and 9 unconventional plant protein meals were pooled to establish the regression equation of DE on IVDE as:DE=0.9813IVDE t187(R^(2)=0.9120,RSD=118 kcal/kg DM,P<0.01).The regression equations to predictME from IVDE in 10 experimental diets and 9 unconventional plant protein meals were ME=0.9559IVDE t146(R^(2)=0.9697,RSD=18 kcal/kg DM,P<0.01)and ME=0.9388IVDEt3(R^(2)=0.8282,RSD=182 kcal/kg DM,P<0.01),respectively.Therewas no statistical difference in slopes(P=0.97)but significant difference between the intercepts(P=0.02)of these 2 equations.Our results indicate IVDE has similar response to the DE but different response to the ME in 10 experimental diets and 9 unconventional plant protein meals.Therefore,IVDE is moresuitable to predict DE than ME of diets and unconventional plant protein meals for growing pigs.
基金financially supported by the Chinese Universities Scientific Fund Chinese Universities Scientific Fund(2017QC040)the 111 Project(B16044)
文摘The objectives of this study were to determine: 1) the effects of konjac flour residues and ramie on digestible energy(DE), metabolizable energy(ME) and apparent total tract digestibility(ATTD) of nutrients in diets fed to growing pigs, 2) the DE and ME contents of konjac flour residues and ramie.Thirty barrows were allotted to 1 of 5 treatments with 6 replicates per treatment.The 5 diets include a corn-soybean meal basal diet(CTL), konjac flour residues diets containing 15% konjac flour residues(LK)or 30% konjac flour residues(HK), and ramie diets containing 15% ramie(LR) or 30% ramie(HR).The experiment lasted 19 days, including 7 days for cage adaptation, 7 days for diet adaptation, and 5 days for total feces and urine collection.The energy values and ATTD of nutrients in each diet were determined,and DE and ME contents of konjac flour residues and ramie were calculated.The results showed that consumption of konjac flour residues significantly increased(P < 0.01) the fecal moisture content compared with the ramie treatment.The LK, HK and HR diets had lower(P < 0.01) DE values compared with the CTL diet.The HR diet had greater(P < 0.01) DE value compared with the HK diet.The LK and LR diets showed greater(P < 0.01) ATTD of DM, OM, GE and CP compared with the HK and HR diets.The HK diet had the lowest(P < 0.01) ATTD of ether extract(EE) among the 5 diets.No differences were observed for the ATTD of NDF and ADF among the 5 diets.Moreover, the DE and ME values of konjac flour residues under 2 inclusion levels(15% and 30%) were 11.66, 11.87 MJ/kg and 10.41, 10.03 MJ/kg, respectively.The corresponding values for ramie were 13.27, 13.16 MJ/kg and 13.07, 12.82 MJ/kg, respectively.In conclusion, the differences in fecal moisture content and the ATTD of EE among the 5 diets were mainly due to the different chemical compositions of konjac flour residues and ramie.Compared with konjac flour residues, ramie has greater DE and ME values under the same inclusion level.
基金supported by the Jilin Academy of Agricultural Sciences (CXGC202107GH,CXGC202003GH)China Agriculture Research System (CARS-41-G11)+1 种基金Shandong Provincial Key Research and Development Program(2019JZZY020602)the Feedstuffs Net Energy Evaluation Funding provided by Huayu Agri-Tech Co.Ltd.
文摘Optimizing the energy utilization of nutrients and ensuring maximum benefits are continuous goals for livestock producers.The net energy(NE)value of feed reflects its nutritional value in the precision feeding system.An experiment was conducted to determine the apparent metabolizable energy(AME)and NE values of 3 types of dephenolized cottonseed protein(DCP)for Hy Line Brown hens aged 42 to 45 weeks using the reference diet substitution method.A reference diet based on corn soybean meal was used to meet the nutritional needs of Hy Line Brown laying hens.To render the crude protein and energy values of the 3 test diets similar,10.5%,12%,and 16%of the gross energy yielding ingredients from the reference diet were replaced with DCP 1,DCP 2,and DCP 3,respectively.The birds were fed 4 diets during a 7-d adaptation period.After the dietary adaptation period,2 birds per replicate from each treatment group were placed in an individual open circuit respiratory calorimetry chamber for a 3-d experimental period.Daily O_(2)consumption and CO_(2)production were recorded,and excreta samples were collected.The AME values of DCP 1,DCP 2,and DCP 3 were 3,049.05,2,820.13,and 2,982.31 kcal/kg of dry matter(DM),respectively.The NE values of DCP 1,DCP 2,DCP 3 were 1,475.77,1,910.31,and 1,905.37 kcal/kg of DM,respectively,and the NE:AME ratios were 48.40%,67.74%,and 63.89%,respectively.Our data show that the AME value of DCP does not reflect the nutritional value of the feed.The NE value of DCP with a high ME value was not necessarily high.
基金CTC Bio,Inc.,Seoul 05720, Republic of Korea for conducting the present experiment is duly acknowledged.
文摘The present study was conducted to test whether the dietary supplementation of β-mannanase affects amino acids(AA) digestibility,metabolizable energy(ME) contents of corn,wheat,soybean meal,distillers dried grains with solubles,and palm kernel meal(PKM),nutrient digestibility,and growth performance of pigs.In Exp.1,22 cannulated pigs were used for 10 dietary treatments including 5 feed ingredients and 2 β-mannanase concentrations(0 and 0.5 g/kg of the diet) in 6 periods in an incomplete Latin square design to determine the AA and energy digestibility.In Exp.2,200 growing pigs were randomly allotted to 4 treatments with 2 nutrient levels(high and low) and 2 concentrations of β-mannanase(2×2 factorial arrangement) in 2 phases(phase 1,d 0 to 21;and phase 2,d 22 to 42).In Exp.1,β-mannanase increased the mean standardized ileal digestibility(SID) of AA in all feed ingredients.The amount of digestible energy was increased(P <0.05) in β-mannanase-treated PKM.Pigs fed β-mannanase showed a greater(P <0.05) digestibility of gross energy(GE).The feed-to-gain(F:G) ratio was improved(P <0.01) in pigs fed high-nutrient diets.Pigs fed β-mannanase in the diets had greater(P <0.05) average daily gain and F:G.In phase 2,the concentration of fecal ammonia was decreased(P <0.05) in pigs fed β-mannanase.Considering the 2 experiments,it can be concluded that β-mannanase increases the SID of AA,which has to be considered in balancing the rations.
基金This study was financially supported by DSM Nutritional Products,Switzerland.
文摘Currently,specific nutrient concentration,metabolizable energy(ME)and digestible amino acids are used as feed formulation criteria.A balanced nutrient density(BND)concept based on 2 criteria of nutrient density and balanced amino acids-to-ME ratio may offer more flexibility in optimisation of profit in formulation of diets compared with current formulation based on set values per unit of feed mass.A total of 672 one-d-old off-sex male Ross 308 broiler chickens were used across two 42-d performance trials in a 3×2 factorial arrangement of treatments with each diet replicated 8 times(14 birds per replicate).The experimental factors were 2 nutrient density levels(low[LD]and high[HD])and 3 digestible lysine-to-ME ratios(DLYS:ME;low,medium,and high).Low density diets had ME of 2,876 and 3,023 kcal/kg for starter and finisher,respectively,while values for HD diets were 3,169 and 3,315 kcal/kg with proportionally higher non-nitrogenated nutrients.Separate digestibility and apparent metaboliz-able energy(AME)assays were conducted at d 21 and 42.Digestibility assays at d 7 were conducted on birds used for performance trials.Regardless of the diet density,birds fed low DLYS:ME had a lower(P<0.01)feed intake(d 0 to 42)than medium and high DLYS:ME.Without interaction,birds fed low and medium DLYS:ME had a similar body weight gain being the heaviest while birds low DLYS:ME were the lightest.By an interaction(P<0.05),the highest overall FCR value was observed for birds fed LD×low DLYS:ME and improved linearly when DLYS:ME increased to the highest level reaching a limit for birds fed HD×medium DLYS:ME.Calorie conversion linearly decreased(P<0.001)with increments in DLYS:ME.Jejunal and ileal starch and protein digestibility were affected on d 21 and 42 but not on d 7 of age.Given the independence of response on BW and feed consumption,the use of BND as a flexible system in diet formulations has the potential to enable more accurate formulation for optimisation of growth performance of broiler chickens.
基金conducted as part of the National Technology Program for Meat Sheep Industry of China (nycytx-39)funded by the Ministry of Agriculture of the People’s Republic of China
文摘A comparative slaughter trial and a metabolism trial were conducted to determine the requirement of net energy （NE） and metabolizable energy （ME） by the crossbreed of German Mutton Merino×Inner Mongolia Merino for fattening from 35 to 50 kg of body weight （BW）. 49 crossbred female lambs （（33.9＋2.3） （SD） kg BW） of German Mutton Merino×lnner Mongolia Merino were used. 34 lambs were randomly chosen for comparative slaughter, which were offered an identical mixture diet （concentrate：roughage=55：45） at 100, 75 or 55% of ad libitum intake, whereas the remainders were used in the metabolism trial to evaluate the ME of the diet after methane production was measured by open-circuit respirometry. As feed intake decreased from 100 to 75 and 55% of ad libitum intake, the apparent digestibility of dry matter （DM） linearly increased （P=-0.010） from 60.8 to 63.6 and 66.9%, respectively, and methane production decreased from 52.1 to 44.3 and 39.9 L d-l, respectively, but the ratio of methane energy to gross energy intake increased linearly （P=0.010） from 8.20 to 8.96 and 10.97%, respectively. Consequently, the ME values of the diet increased from 9.35 to 9.64 and 9.85 MJ kg-~ DM, respectively. The NE requirement for maintenance （NEro） was 255 kJ kg-1 BW0.75, and the ME requirement for maintenance （MEre） was 352 kJ kg-I BW~.75, with a partial energy efficiency for maintenance （km） of 0.72. The NE requirement for growth （NEg） ranged from 1.26 to 4.66 MJ d-1as average daily gains increased from 100 to 300 g d-1, with a partial energy efficiency for growth （ks） of 0.45. These results indicated that the NEg required by crossbred female lambs of German Mutton Merinoxlnner Mongolia Merino was lower than the recommendation of the American or British nutritional system.
