Background During the transition period,cows are prone to negative energy balance,which can lead to a decline in production performance and health in severe cases.In recent years,it has been discovered that bile acids...Background During the transition period,cows are prone to negative energy balance,which can lead to a decline in production performance and health in severe cases.In recent years,it has been discovered that bile acids(BAs)can act not only as fat emulsifiers but also as signaling molecules to regulate body metabolism.Although BAs have been used to some extent in monogastric and aquatic animals,their role in ruminants,particularly in transition cows,remains unclear.Therefore,this study aimed to determine the effects of BAs on the production performance,milk and plasma fatty acid and BA composition,and fecal microbiota in transition dairy cows.Results Forty-six healthy transition Holstein dairy cows with similar conditions were randomly divided into two groups and supplemented with 0 or 20 g/d of BAs from 21 d before the expected calving to 21 d after calving.The production performance was tracked until 60 d after calving.The results indicated that BA supplementation significantly improved postpartum milk fat content and yields as well as the yields of unsaturated fatty acids,monounsaturated fatty acids,and polyunsaturated fatty acids in milk.There was a significant increase in the concentration of triglyceride and the proportion of C≤16 fatty acids in the plasma of cows supplemented with BAs,while the concentration of β-hydroxybutyrate and the proportion of C>16 fatty acids in the plasma decreased significantly.BA supplementation significantly altered the composition of the fecal bacterial community and increased the relative abundance of bacteria beneficial for BA metabolism and transformation(Romboutsia,Clostridium sensu_stricto_6,and Clostridium sensu_stricto_1).Functional prediction analysis showed that the relative abundance of bile salt hydrolase,7 α-hydroxysteroid dehydrogenase,and BA inducible E as well as the pathways related to BA metabolism also significantly increased in cows supplemented BAs.In addition,BA supplementation significantly altered the composition of plasma and fecal BAs,particularly increasing circulating secondary BA concentration,which might induce the complete oxidation of fatty acids in the liver and further reduce the concentration of β-hydroxybutyrate.Conclusions These findings highlight the potential benefits of BA supplementation in improving milk yields and quality,as well as influencing metabolic pathways in transition dairy cows.Meanwhile,further studies are needed to elucidate the underlying mechanisms and explore the broader implications of these results by using more tissue samples.展开更多
In this study, feed-grade proteinase was added into conventional diets of three-line crossbred （Duroc x Landrace x Large White） piglets, to investigate the effects of feed-grade proteinase on anti-diarrhea capacity,...In this study, feed-grade proteinase was added into conventional diets of three-line crossbred （Duroc x Landrace x Large White） piglets, to investigate the effects of feed-grade proteinase on anti-diarrhea capacity, daily weight gain, feed intake and feed conversion ratio of piglets. The results showed that adding feed-grade proteinase in diets enhanced anti-diarrhea capacity of piglets and improved signifi- cantly production performance and breeding efficiency of piglets. This study provided the reference for rational utilization of feed-grade proteinase in actual production.展开更多
Yak ( Bos grunniens ) is classified as Bovine genus,they live in Qingzang Plateau with elevation more than 3500m and it's neighbor highland,where the weather is high chilly,short of oxygen and large difference o...Yak ( Bos grunniens ) is classified as Bovine genus,they live in Qingzang Plateau with elevation more than 3500m and it's neighbor highland,where the weather is high chilly,short of oxygen and large difference of temperature between day and night.But yak have adapted that circumstance after thousands of years' artificial and natural selection and has great anti adversity capacity.Yak is an important sustenance and means of production to Tibetan.China is a country with the largest number of yak,whose amount of livestock on hand accounts for 95% of the world and Tibet region takes the second place next to Qinghai in the number of yak.Tibetan yak has formed some groups for Tibetan's large area,complicated geological ecosystem conditions,geological isolation.The typical better groups are Yadong yak,Jiali yak and Sibu yak. Study about yak fell behind other animals due to the restriction of inconvenient transportation,difficult sampling and poor experimental technology.Study about the relationship between yak blood enzyme activities and milk production was little,only Jing (1992) studied correlation of milk production with serum amylase,esterase in Gansu Jiulong yak,Maiwa yak and no report was found in other groups.This study discussed six Jiali yak blood enzyme activities lactate dehydrogenase (LDH),alkaline phosphatases (AKP),acid phosphatase (ACP),catalase (CAT),amylase (Amy) and superoxide dismutase (SOD),and explored their relationship with milk production in Jiali yak,so as to supply with theoretical evidence by using blood enzyme activity as biochemical assisted selection marker in the breeding of Tibetan yak milk yield. This experiment investigated activity of six blood enzymes from 28 Tibetan yaks and explored its relationship to production performance.The results showed a extremely positive significant difference ( P <0.01) between activity of LDH and milk yield,CAT activity and length of belly hair respectively,while a positive significant difference ( P <0.05) was observed between AKP activity and body weight,Amy activity and body weight and a negative significant difference ( P <0.05) for SOD activity and body weight.Stepwise Regression Analysis showed that activity of LDH could be used for the prediction of milk yield,AKP,CAT,Amy for body weight,CAT,Amy for length of belly hair.So it is expected to use activity of LDH,AKP,CAT,Amy as biochemical genetic marker in the selection of milk yield,body weight and length of belly hair.展开更多
ln the research, an empirical analysis was performed on production per-formance and influential factors of rice in Changsha County and Liling City. The re-sults showed that production scale has been closely linked to ...ln the research, an empirical analysis was performed on production per-formance and influential factors of rice in Changsha County and Liling City. The re-sults showed that production scale has been closely linked to age and education level of farmers. The larger scale, the higher comprehensive performance, but rele-vant efficiency tends to be lower. Sowing area and yield per unit area are major in-fluential factors of production performance of double-cropping rice, but the rest influ-ential factors are different upon production scale. Final y, developmental strategies are proposed for development of double-cropping rice.展开更多
[ Objective ] To analyze the hair and villus production performance of Tianzhu white yak and thus provide conditions for the genetic breed ing and product development. [Method] The hair and villus yield as well as vil...[ Objective ] To analyze the hair and villus production performance of Tianzhu white yak and thus provide conditions for the genetic breed ing and product development. [Method] The hair and villus yield as well as villus rate of male and female Tianzhu white yaks from one year to six years old was detected and the villus yield was also determined. And these indexes of hair and villus were analyzed to evaluate the production per formance. [ Result] In Tianzhu white yaks from one year to two years old, the hair and villus yield was lower, but the villus rate and yield were high er. The hair and villus yield, villus rate, and villus yield were all higher in Tianzhu white yaks from three years to six years old but significantly de creased in 7yearold Tianzhu white yaks. In addition, the hair and villus yield was significantly （ P 〈 0.05） or very significantly （ P 〈 0.01 ） higher in male yaks than in female yaks. The villus rate was very significantly （ P 〈0.01 ） higher than in female yaks from five years to seven years old than in male yaks at the same age. [ Conclusion] Tianzhu white yaks from one year to two years old have the best hair and villus production perform ance; Tianzhu white yaks from three years to six years old are in the main phase of hair and villus production; Tianzhu white yaks older than seven years old should not be used for hair and villus production.展开更多
This study investigated whether competitive reduction of pathogenic bacteria growth in pond water alleviates lipopolysaccharide （LPS） contamination and improves geese production performances in the ＂goose-fish＂ pr...This study investigated whether competitive reduction of pathogenic bacteria growth in pond water alleviates lipopolysaccharide （LPS） contamination and improves geese production performances in the ＂goose-fish＂ production system, thereby providing the potential for an improved technique for ecological water fowl production. In the first experiment, 240 Magang goslings of 15-d age were randomly and equally allocated into 16 ＂yard and pond＂ pens using a 2-2 factorial design with 4 replications per treatment. In the 55-d experimental period, the goslings received 2 main treatments： supplementation of Bacillus subtilis spores in the feed and addition of photosynthetic bacteria （PSB） to the pond water. Both B. subtilis spores and PSB treatments significantly suppressed water counts of Gram-negative bacteria Escherichia coli, Salmonella and Shigella, and LPS concentrations in pond water and in gosling blood （P〈0.05）. As the result, the two treatments significantly improved gosling weight gain and carcass quality, marked by enhanced breast and leg muscle percentages and reduced subcutaneous fat proportions （P〈0.05）. Moreover, the improved effects of B. subtilis spores and PSB treatments were additive. In the second experiment, 1 160 adult geese were induced to start egg laying from May throughout the summer months. The geese were separated equally into control and experimental flocks to fit into 2 integration production units, with a density of 1 bird m-2 meter on pond water. Experimental flock geese were treated with B. subtilis spores in feed and PSB in the pond water for the duration of the study. Such treatment combination significantly depressed the growth of E. coli, Salmonella and Shigella in the pond water and reduced LPS concentrations both in pond water and in geese blood （P〈0.01）. As a result, egg fertility, fertile and set egg hatchabilities were all improved in the treated flock. Results from both growing goslings and breeding geese demonstrated that water bacteria pollution can be competitively reduced by supplementation with B. subtilis spores via the feed and addition of PSB in pond water, each of which reduces LPS contamination to geese and improves production performances. Micro- ecological agents such as B. subtilis spores and PSB improve water quality and provide a simple ecological technique for the ＂water fowl-fish＂ integrative production system.展开更多
The present research was designed to study the association of polymorphism of natural resistance-associated macrophage proteinl （Nrampl） with some immune function and the production performance in Large White pig. T...The present research was designed to study the association of polymorphism of natural resistance-associated macrophage proteinl （Nrampl） with some immune function and the production performance in Large White pig. The PCR-RFLP technique was applied to analyze the correlation between the polymorphisms of Nrampl gene and immune function [value of Polymorphonuclear Leukocytes （PMN） obtained by Nitroblue Tetrazolium （NBT） Reduction and effect of Cytotoxin in Monocyte] and production performance in 165 Large White pigs. The results showed that there was one Nde I restriction locus in Large White pig, and both values of PMN by NBT Reduction and effect of Cytotoxin in Monocyte in genotype BB were higher than those in genotype AB （P〈0.05）. Simultaneously, the weight of 180-day-old pigs with genotype BB was higher than that with genotype AB （P〈0.05）. The results indicated that there was a significant correlation between different genotypes of Nrampl gene and Immune function and production performance, and it can be regarded as a candidate gene of disease resistance. All these results provide valuable reference to further studies of pig disease resistance.展开更多
A comprehensive and precise analysis of shale gas production performance is crucial for evaluating resource potential,designing a field development plan,and making investment decisions.However,quantitative analysis ca...A comprehensive and precise analysis of shale gas production performance is crucial for evaluating resource potential,designing a field development plan,and making investment decisions.However,quantitative analysis can be challenging because production performance is dominated by the complex interaction among a series of geological and engineering factors.In fact,each factor can be viewed as a player who makes cooperative contributions to the production payoff within the constraints of physical laws and models.Inspired by the idea,we propose a hybrid data-driven analysis framework in this study,where the contributions of dominant factors are quantitatively evaluated,the productions are precisely forecasted,and the development optimization suggestions are comprehensively generated.More specifically,game theory and machine learning models are coupled to determine the dominating geological and engineering factors.The Shapley value with definite physical meaning is employed to quantitatively measure the effects of individual factors.A multi-model-fused stacked model is trained for production forecast,which provides the basis for derivative-free optimization algorithms to optimize the development plan.The complete workflow is validated with actual production data collected from the Fuling shale gas field,Sichuan Basin,China.The validation results show that the proposed procedure can draw rigorous conclusions with quantified evidence and thereby provide specific and reliable suggestions for development plan optimization.Comparing with traditional and experience-based approaches,the hybrid data-driven procedure is advanced in terms of both efficiency and accuracy.展开更多
For extra-low permeability reservoirs, with a permeability of about 0.3×10?3 μm2, fluid flow and production performance in cores were studied. A long core holder with a multi-location piezometric measurement was...For extra-low permeability reservoirs, with a permeability of about 0.3×10?3 μm2, fluid flow and production performance in cores were studied. A long core holder with a multi-location piezometric measurement was specially designed. An artificial long core, about 700 mm long and with a cross section of 45mm×45mm, was used. In the experiment, pressure distribution along the core can be measured in real time. Single phase flow in the core was investigated. Different modes of production in long cores were also simulated including natural depletion, water flooding, and advanced water flooding. Through physical simulation, flow parameters were collected and production characteristics in extra-low permeability cores were studied. From experimental results, it can be seen that fluid flow in extra-low permeability cores is different from that in high permeability cores. Transmission of pressure in extra-low permeability cores is very slow, and it needs a long time for the pressure to become stable. The distribution curve of pressure along the core is nonlinear and the production rate in extra-low permeability reservoirs decreases sharply. The development effects of different production modes in extra-low permeability cores were compared with one another. Among the production modes, advanced water flooding has much potential for effective development of extra-low permeability reservoirs. Natural depletion and conventional water flooding can also be used in early production periods. In addition, the countermeasures and some ideas especially for the potential development of extra-low permeability reservoirs are suggested.展开更多
[ Objectives ] To study the effects of low-protein diets supplemented with amino acids on the production performance, carcass quality and input-output ratio of fattening pigs and growing-finishing pigs. [ Methods] Two...[ Objectives ] To study the effects of low-protein diets supplemented with amino acids on the production performance, carcass quality and input-output ratio of fattening pigs and growing-finishing pigs. [ Methods] Two studies were conducted on fattening pigs and growing pigs respectively. Pigs in two experimental groupswere fed with low-protein diets supplemented with amino acids and normal diets respectively, and the initial weight, final weight, feed consumption and car- cass index of the tested pigs were measured. [ Results] The average final weight of fattening pigs in test group was 2.4 kg lower than that in control group, while the difference was not significant （P 〉 0.05 ）. The average daily gain of fattening pigs in test group was 60 g lower than that in control group, indicating that low protein diets had a tendency to decrease the growth rate （P 〉 0.05 ）, and reduction of daily weight gain in low protein diet pigs reached 7.6%. The development of pigs in low protein diet group was poor, however, the difference was not significant. Carcass backfat thickness in low-protein diet group was slightly higher than that in control group, the difference was significant （ P 〈 0.05 ）. There was no significant difference in input-output ratio between low-protein diet group and control group. Finalweight of growing-finishing pigs in low-protein diet group was 3.22 % lower than that in control group, the average daily weight gainwas 6.91% lower than that in control group, feed intake in test group was 5.48% lower than that in control group, and difference between the two treatments was significant （P 〈 0.05 ）. Feed meat ratio in low-protein diet group improved, however, the difference was not significant（P 〉0.05）. [ Conclusions] Production performance of the pigs would be decreasedand the input-output ratio could not be improvedwhen the adding contents of crude protein in diets was reduced 3% -4%. Therefore, it is recommended that the crude protein level should be enough when pigs were fed with low-protein diets.展开更多
[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1&...[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1"laying hens(66 weeks of age)in late period of laying were randomly divided into four groups,six replicates each group,and each group had 27 individuals of laying hens.The laying hens in control group were fed with basal diet,and those in experimental groupsⅠ,Ⅱ and Ⅲ were fed with the basal diets added with 3.33×10^6,1×10^7,3.33×10^7 CFU/g B.coagulans,respectively.The pretrial lasted one week,and the formal test lasted eight weeks.[Result]Compared with the control group,the laying rate in group Ⅰ increased significantly,and the feed-gain ratio in experimental group Ⅱ decreased noticeably while the spleen index increased remarkably;the alkaline phosphatase activities and blood calcium content in experimental groups Ⅰ,Ⅱ and Ⅲ increased significantly(P<0.05),while the triglyceride content decreased remarkably(P<0.05);the urea content in experimental groups Ⅰ and Ⅱ decreased obviously(P<0.05).Adding B.coagulans significantly increased the specific activity of amylase,lipase and protease in various intestinal mucosa of small intestine(P<0.05);adding B.coagulans significantly increased the content of follicle-stimulating hormone(FSH)and estradiol(E2),and significantly increased the mRNA expression of follicle stimulating hormone receptor gene(FSHR).[Conclusion]B.coagulans preparation could significantly improve the production performance of laying hens in late period of laying;appropriately enhance the immune capacity of laying hens;improve the serum biochemical indicators;increase the activity of digestive enzymes in the small intestine;and promote the release of gonadal hormone and the mRNA expression of FSHR gene in the ovary.展开更多
Twenty lactating cows of two to five parity having an average live weight of 290.00 to 330.00 kg and an average milk production of 4.54 kg/head/day to 4.66 kg/head/day were selected from the Central Cattle breeding St...Twenty lactating cows of two to five parity having an average live weight of 290.00 to 330.00 kg and an average milk production of 4.54 kg/head/day to 4.66 kg/head/day were selected from the Central Cattle breeding Station and Dairy Farm. The four dietary treatment were： SlooTo （Straw 100： Triticale 0 as control）; $5oT5o （Straw 50： Triticale 50）; $25T75 （Straw 25： Triticale 75） and SoTloo （Straw 0： Triticale 100）. It was observed that the roughage dry matter intake （DMI） （2.61 ~ 0.07 kg） in percent live weight was significantly （P 〈 0.05） higher in $25T75 and the lowest （1.76 ~ 0.018 kg） in the control group （SlooTo） and the differences were significant among the dietary treatments except $5oT5o and SoTloo. The total DMI was significantly （P 〈 0.05） higher in SoT^oo （13.36 i 0.13 kg） followed by $25T75, $5oT5o and SlooTo, respectively. The digestibility of crude protein （CP） was slightly higher in $25T75 （75.48 ~ 0.96） compared to SoTtoo （75.31 ~ 1.45） and the difference was non-significant （P 〉 0.05）. Milk production was significantly （P 〈 0.05） the highest in $5oT5o and the lowest in SlooTo followed by SoTloo, $25T75, respectively. The percent increased in milk yield was also the highest in $5oT5o （67.68%） and the lowest in SlooTo （28.85%）. The 4% fat corrected milk was also significantly （P 〈 0.05） higher in $5oT5o followed by SoTloo, $25T75 and SlooTo, respectively. Therefore, it can be concluded that triticale and straw at a ratio of 50：50 may be fed for better production performance of dairy cows.展开更多
Production performance of four forage legumes species of Medicago sativa,Onobrychis viciifolia,Lotus corniculatus and Galega officinalis were determined,including plant height,above-ground biomass per unit area,tiller...Production performance of four forage legumes species of Medicago sativa,Onobrychis viciifolia,Lotus corniculatus and Galega officinalis were determined,including plant height,above-ground biomass per unit area,tillers per unit area,fertile tillers per unit area,shoot /leaf ratio and fresh /dry matter weight ratio,and the distribution characteristics of their root systems in 0- 100 cm soil layers with 10 cm interval were studied. Results showed that the average aboveground fresh biomass(4 a and 5 a) of four forage legumes species successively were L. corniculatus 】 M. sativa 】 O. viciifolia 】 G. officinalis. The average plant heights in two years successively were O. viciifolia 】 M. sativa 】 G. officinalis 】 L. corniculatus. Tillers per unit area of four forage legume species in two years successively were M. sativa 】 L. corniculatus 】 O. viciifolia 】 G. officinalis. Fertile tillers per unit area in two years were O. viciifolia 】 M. sativa 】 L. corniculatus 】 G. officinalis. Average shoot /leaf ratio in two years were G. officinalis 】 M. sativa 】 O. viciifolia 】 L. corniculatus. Average moisture contents of four forage legume species in two years successively were G. officinalis 】 L. corniculatus 】 M. sativa = O. viciifolia. The distribution characteristics of root systems of four forage legumes species in 0- 100 cm soil layers were as follows: the root weights of M. sativa in 0- 40 cm soil layers accounted for about 98. 3% of total root weight,that of O. viciifolia in 0- 30 cm soil layers was 85. 8%,that of L. corniculatus in 0- 10 cm soil layers was 80%,and that of G. officinalis in 0- 40 cm soil layers was 81. 4%. The results suggested that L. corniculatus was suited to plant in slighter degraded pasture to control water and soil erosion in early stage,G. officinalis with strong lateral roots was adapted to degraded grassland in the Loess Plateau where soil nutrient was poor,while O. viciifolia and M. sativa with potentially strong main root were fit for water and soil conservation in the losses plateau for long term.展开更多
Domestic and foreign researches on triticale mainly focus on hereditary traits and excellent characteristics,but there are few reports on triticale yield and quality in the severe cold pastoral areas of Gansu and Qing...Domestic and foreign researches on triticale mainly focus on hereditary traits and excellent characteristics,but there are few reports on triticale yield and quality in the severe cold pastoral areas of Gansu and Qinghai.In this study,Gannong 2 triticale cultivars have been bred and planted in typical ecological areas according to the characteristics of different ecological regions.By studying the relationship between quality traits and various ecological factors,the effects of different ecological factors on the quality of Triticale hay have been clarified,which provides a reasonable basis for future triticale breeding and large-scale and targeted planting layout.The production performance and nutritional qualities of Triticale Trial in Maqu County,Gansu Province and Gannong No.2 in Dulan County,Qinghai Province are obviously superior to other pilot sites.Through reasonable fertilization,the production performance and nutritional quality of triticale are the best.Triticale production performance is significantly related to climatic factors in different pilots.The most suitable planting area for Gannong 2 is Maqu County,Gansu Province.展开更多
The aim of this study was to investigate the effects of </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;...The aim of this study was to investigate the effects of </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;"> and its fermentation products on performance, blood hormone levels and rumen floral composition in peripartum dairy cows. Sixty perinatal cows were selected and allocated to two groups according to parity and expected date of delivery. Each group was supplemented with </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;"> and its fermentation product 0 or 100 g. The results showed that </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;"> and its fermentation products could significantly increase the feed intake of peripartum dairy cows (P < 0.01), increase the lactose content after 21 days postpartum (P < 0.01), and tend to increase milk production (P = 0.052). There was no significant effect on other milk components, the apparent digestibility of nutrients. There was a tendency to increase milk production and reduce the number of somatic cells in milk;increase blood levels of glucagon (P < 0.01) and </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-hydroxybutyrate (P = 0.01), reducing the insulin content (P = 0.02).</span></span><span style="font-family:""> </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:""><span style="font-family:Verdana;"> reduced the abundance of rumen microbes in peripartum dairy cows but had no effect on rumen microbial diversity. Compared with the control group, the supplemented group showed reductions in the abundance of genera </span><i><span style="font-family:Verdana;">Bacillus</span></i><span style="font-family:Verdana;"> (P = 0.03), </span><i><span style="font-family:Verdana;">Butyrivibrio</span></i><span style="font-family:Verdana;"> (P = 0.01), </span><i><span style="font-family:Verdana;">Denitrobacterium</span></i><span style="font-family:Verdana;"> (P = 0.01), and </span><i><span style="font-family:Verdana;">Mogibacterium</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Porphyromonas</span></i><span style="font-family:Verdana;"> (P = 0.05), </span><i><span style="font-family:Verdana;">Saccharofermentans</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Sphaerochaeta</span></i><span style="font-family:Verdana;"> (P = 0.02), </span><i><span style="font-family:Verdana;">Streptococcus</span></i><span style="font-family:Verdana;"> (P = 0.04) and other genera. There were significant increase in the content of </span><i><span style="font-family:Verdana;">Acidaminococcus</span></i><span style="font-family:Verdana;"> (P = 0.03), </span><i><span style="font-family:Verdana;">Allisonella</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Bulleidia</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Corynebacterium</span></i><span style="font-family:Verdana;"> (P = 0.01), </span><i><span style="font-family:Verdana;">Dialister</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Faecalibacterium</span></i><span style="font-family:Verdana;"> (P = 0.02), </span><i><span style="font-family:Verdana;">Faekalitalea</span></i><span style="font-family:Verdana;"> (P = 0.03), </span><i><span style="font-family:Verdana;">Fibrobacter</span></i><span style="font-family:Verdana;"> (P = 0.04), </span><i><span style="font-family:Verdana;">Flavobacterium</span></i><span style="font-family:Verdana;"> (P = 0.03), </span><i><span style="font-family:Verdana;">Kandleria</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Paraprevotella</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Pyramidobacter</span></i><span style="font-family:Verdana;"> (P = 0.05), </span><i><span style="font-family:Verdana;">Roseburia</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Succinivibrio</span></i><span style="font-family:Verdana;"> (P < 0.01) and other genera.</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">The main metabolic pathways such as tryptophan metabolism and steroid hormone biosynthesis in perinatal dairy cows were determined for </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;"> and its fermentation products.展开更多
[Objective]In order to research on effect of different content of cottonseed meals on production performance and egg quality of Hisex laying hens. [Methods]120 Hisex laying hens of 37 weeks old are chosen,randomly div...[Objective]In order to research on effect of different content of cottonseed meals on production performance and egg quality of Hisex laying hens. [Methods]120 Hisex laying hens of 37 weeks old are chosen,randomly divided into four groups and three repetitions are set in each group,there are 10 hens in each repetition. Group I is the control group,II,III and IV are experimental groups. Cottonseed meal contents are respectively 5%,10% and 15%,with test cycle of 10 weeks,effects of different cottonseed meal dosages on Hisex laying hens production performance and egg quality are observed. [Results]When the diet is added with 5% to 15% of cottonseed meal,the average laying rate,average egg weight and feed-gain ratio all show downward trends when compared with that of the control group,but with no significant difference（ P 〉 0. 05）; eggshell strength,eggshell thickness,Haugh unit,egg shape index all show no significant difference（ P 〉0. 05）,with the increasement of cottonseed meal,the color of egg yolk got brighter,egg yolk color of 15% added group increased by 12%,show a significant difference with that of control group（ P 〈0. 05）. [Conclusion]When the feed was added with 15% cottonseed meals,it has an unconspicuous effect on laying performance and egg quality of Hisex laying hens,but whether it had an effect on animal health and food safety or not,a further systematic research is needed.展开更多
Volume fracturing technology has been widely applied in the development of coalbed methane(CBM)reservoirs.As for the stimulated reservoir volume(SRV)created by volume fracturing,the seepage laws of fluids are describe...Volume fracturing technology has been widely applied in the development of coalbed methane(CBM)reservoirs.As for the stimulated reservoir volume(SRV)created by volume fracturing,the seepage laws of fluids are described more accurately and rationally in the rectangular composite model than in the traditional radial composite model.However,the rectangular composite model considering SRV cannot be solved using the analytical or semi-analytical function method,and its solution from the linear flow model has larger errors.In view of this,SRVareas of CBM reservoirs were described by means of dual-medium model in this paper.The complex CBM migration mechanisms were investigated comprehensively,including adsorption,desorption,diffusion and seepage.A well testing model for rectangular composite fracturing wells in CBM reservoirs based on unsteady-state diffusion was built and solved using the boundary element method combined with Laplace transformation,Stehfest numerical inversion and computer programming technology.Thus,production performance laws of CBM reservoirs were clarified.The flow regimes of typical well testing curves were divided and the effects on change laws of production performance from the boundary size of gas reservoirs,permeability of volume fractured areas,adsorption gas content,reservoir permeability and SRV size were analyzed.Eventually,CBM reservoirs after the volume fracturing stimulation were described more accurately and rationally.This study provides a theoretical basis for a better understanding of the CBM migration laws and an approach to evaluating and developing CBM reservoirs efficiently and rationally.展开更多
To explore the effect of different additive combinations on double-low rapeseed cake （meal） utilization and layer production performance, we randomly divided 756 Roman brown shell layers around 50 weeks age into sev...To explore the effect of different additive combinations on double-low rapeseed cake （meal） utilization and layer production performance, we randomly divided 756 Roman brown shell layers around 50 weeks age into seven groups to detect production performance, of which group 1 was control group supplied with basic diet （added with 9% double-low rapeseed cake）, while groups 2 -7 were experimental groups added with Chinese herbal medicine, enzyme preparation, pro- biotics and peptide antibiotics in basic diet. The results showed that group 4 added with Chinese herbal medicine ＋ enzyme preparation ＋ peptide antibiotics re- ceived the best effect, resulting in significantly increased laying rate （70.50%, P 〈 0.05 ）, significantly reduced feed-egg ratio （2.46, P 〈 0.05 ）, and extremely increased egg Haugh unit （P 〈0.01 ）. This indicated that adding combination of Chinese herbal medicine ＋ enzyme preparation ＋ peptide antibiotics in layer bas- ic diet could improve egg production performance and egg quality of layers.展开更多
Using a multi-input multi-output production technology and survey data from Jinzhai County, western Anhui Province, China, the author first measured the production performance of rural households their efficiency, ec...Using a multi-input multi-output production technology and survey data from Jinzhai County, western Anhui Province, China, the author first measured the production performance of rural households their efficiency, economy of scale, and productivity during 19781997, and then related the measured production performance with institutional change, market access, and other factors. Preliminary results show that: 1) performance differs a great deal across households and over time; 2) institutional changes and market accessibility have played a major role in improving performance; 3) depending on the specific resources, their effects are variable.展开更多
In this study,the effects of two types of premixed materials with different combinations of trace elements on the production performance and antioxidant capacity of simmental beef cattle were examined.Fifteen healthy ...In this study,the effects of two types of premixed materials with different combinations of trace elements on the production performance and antioxidant capacity of simmental beef cattle were examined.Fifteen healthy simmental beef cattle of similar weight(approximately 330 kg),the same age(12 months),without castration,and a good physique were divided into three groups,with five beef cattle in each group.Food of Group Ⅰ beef cattle was supplemented with a commercially marketed 5% compound trace element premixture for fine beef cattle.Food of Group Ⅱ beef cattle was supplemented with a 5% compound microelement premixture for beef cattle that was designed to address local nutrient deficiencies and surpluses.In the blank control group,the beef cattle were not fed a premixture.The pretest period was 15 days,and the test period was divided into prefattening(45 days)and postfattening(45 days)stages.Body weight and body size indices were recorded at 1,2 and 3 months,and blood samples were collected regularly.In Group Ⅰ,the daily weight gain increased significantly by 15.7% compared with that of the control group.The largest daily weight gain was in Group Ⅱ,which increased by 31.6% compared with that in the control.During the test period of 90 days,the body size indices of the three different groups increased in different months,with significant increases in the indices for both test groups compared with those of the control.In Group Ⅰ,the activity of CP,the total activity of SOD and Cu-Zn-SOD increased significantly(p<0.05)compared with those in the control group,with a highly significant increase observed in GSH-PX activity(p<0.01).In Group Ⅱ,the increases in the activity of CP and the total activity of SOD and Cu-Zn-SOD were highly significant compared with those in the control group(p<0.01).In addition,a significant increase was observed in GSH-PX activity(p<0.05).Based on pretest results,the concentrations of Cu,Zn,Mo,Mn,Se and Co in the blood of experimental beef cattle were lower than those of the normal range.After feeding for 90 days,the concentrations of Cu,Zn,Mo,Mn,Se and Co in the blood of Groups Ⅰ and Ⅱ were significantly higher than those in the control group(p<0.05).The concentrations of elements in the blood of Group Ⅱ were close to the appropriate levels.Thus,the effects of the specifically designed compound microelement premixture on the prevention of nutrient imbalances and control of beef cattle nutrition metabolism and the production of fattened beef cattle were significant.展开更多
基金supported by the National Center of Technology Innovation for Dairy(No.2024-JSGG-021)the National Natural Science Foundation of China(No.32102570)the Key Research and Development Project of Ningxia(No.2024BBF01006).
文摘Background During the transition period,cows are prone to negative energy balance,which can lead to a decline in production performance and health in severe cases.In recent years,it has been discovered that bile acids(BAs)can act not only as fat emulsifiers but also as signaling molecules to regulate body metabolism.Although BAs have been used to some extent in monogastric and aquatic animals,their role in ruminants,particularly in transition cows,remains unclear.Therefore,this study aimed to determine the effects of BAs on the production performance,milk and plasma fatty acid and BA composition,and fecal microbiota in transition dairy cows.Results Forty-six healthy transition Holstein dairy cows with similar conditions were randomly divided into two groups and supplemented with 0 or 20 g/d of BAs from 21 d before the expected calving to 21 d after calving.The production performance was tracked until 60 d after calving.The results indicated that BA supplementation significantly improved postpartum milk fat content and yields as well as the yields of unsaturated fatty acids,monounsaturated fatty acids,and polyunsaturated fatty acids in milk.There was a significant increase in the concentration of triglyceride and the proportion of C≤16 fatty acids in the plasma of cows supplemented with BAs,while the concentration of β-hydroxybutyrate and the proportion of C>16 fatty acids in the plasma decreased significantly.BA supplementation significantly altered the composition of the fecal bacterial community and increased the relative abundance of bacteria beneficial for BA metabolism and transformation(Romboutsia,Clostridium sensu_stricto_6,and Clostridium sensu_stricto_1).Functional prediction analysis showed that the relative abundance of bile salt hydrolase,7 α-hydroxysteroid dehydrogenase,and BA inducible E as well as the pathways related to BA metabolism also significantly increased in cows supplemented BAs.In addition,BA supplementation significantly altered the composition of plasma and fecal BAs,particularly increasing circulating secondary BA concentration,which might induce the complete oxidation of fatty acids in the liver and further reduce the concentration of β-hydroxybutyrate.Conclusions These findings highlight the potential benefits of BA supplementation in improving milk yields and quality,as well as influencing metabolic pathways in transition dairy cows.Meanwhile,further studies are needed to elucidate the underlying mechanisms and explore the broader implications of these results by using more tissue samples.
文摘In this study, feed-grade proteinase was added into conventional diets of three-line crossbred （Duroc x Landrace x Large White） piglets, to investigate the effects of feed-grade proteinase on anti-diarrhea capacity, daily weight gain, feed intake and feed conversion ratio of piglets. The results showed that adding feed-grade proteinase in diets enhanced anti-diarrhea capacity of piglets and improved signifi- cantly production performance and breeding efficiency of piglets. This study provided the reference for rational utilization of feed-grade proteinase in actual production.
文摘Yak ( Bos grunniens ) is classified as Bovine genus,they live in Qingzang Plateau with elevation more than 3500m and it's neighbor highland,where the weather is high chilly,short of oxygen and large difference of temperature between day and night.But yak have adapted that circumstance after thousands of years' artificial and natural selection and has great anti adversity capacity.Yak is an important sustenance and means of production to Tibetan.China is a country with the largest number of yak,whose amount of livestock on hand accounts for 95% of the world and Tibet region takes the second place next to Qinghai in the number of yak.Tibetan yak has formed some groups for Tibetan's large area,complicated geological ecosystem conditions,geological isolation.The typical better groups are Yadong yak,Jiali yak and Sibu yak. Study about yak fell behind other animals due to the restriction of inconvenient transportation,difficult sampling and poor experimental technology.Study about the relationship between yak blood enzyme activities and milk production was little,only Jing (1992) studied correlation of milk production with serum amylase,esterase in Gansu Jiulong yak,Maiwa yak and no report was found in other groups.This study discussed six Jiali yak blood enzyme activities lactate dehydrogenase (LDH),alkaline phosphatases (AKP),acid phosphatase (ACP),catalase (CAT),amylase (Amy) and superoxide dismutase (SOD),and explored their relationship with milk production in Jiali yak,so as to supply with theoretical evidence by using blood enzyme activity as biochemical assisted selection marker in the breeding of Tibetan yak milk yield. This experiment investigated activity of six blood enzymes from 28 Tibetan yaks and explored its relationship to production performance.The results showed a extremely positive significant difference ( P <0.01) between activity of LDH and milk yield,CAT activity and length of belly hair respectively,while a positive significant difference ( P <0.05) was observed between AKP activity and body weight,Amy activity and body weight and a negative significant difference ( P <0.05) for SOD activity and body weight.Stepwise Regression Analysis showed that activity of LDH could be used for the prediction of milk yield,AKP,CAT,Amy for body weight,CAT,Amy for length of belly hair.So it is expected to use activity of LDH,AKP,CAT,Amy as biochemical genetic marker in the selection of milk yield,body weight and length of belly hair.
基金Supported by Key Financial Program of Hunan Province([2014]74)National Natural Science Foundation of China(41601097)Science&Technology Innovation Project of Hunan Academy of Agriculture Sciences(2016JC08)~~
文摘ln the research, an empirical analysis was performed on production per-formance and influential factors of rice in Changsha County and Liling City. The re-sults showed that production scale has been closely linked to age and education level of farmers. The larger scale, the higher comprehensive performance, but rele-vant efficiency tends to be lower. Sowing area and yield per unit area are major in-fluential factors of production performance of double-cropping rice, but the rest influ-ential factors are different upon production scale. Final y, developmental strategies are proposed for development of double-cropping rice.
文摘[ Objective ] To analyze the hair and villus production performance of Tianzhu white yak and thus provide conditions for the genetic breed ing and product development. [Method] The hair and villus yield as well as villus rate of male and female Tianzhu white yaks from one year to six years old was detected and the villus yield was also determined. And these indexes of hair and villus were analyzed to evaluate the production per formance. [ Result] In Tianzhu white yaks from one year to two years old, the hair and villus yield was lower, but the villus rate and yield were high er. The hair and villus yield, villus rate, and villus yield were all higher in Tianzhu white yaks from three years to six years old but significantly de creased in 7yearold Tianzhu white yaks. In addition, the hair and villus yield was significantly （ P 〈 0.05） or very significantly （ P 〈 0.01 ） higher in male yaks than in female yaks. The villus rate was very significantly （ P 〈0.01 ） higher than in female yaks from five years to seven years old than in male yaks at the same age. [ Conclusion] Tianzhu white yaks from one year to two years old have the best hair and villus production perform ance; Tianzhu white yaks from three years to six years old are in the main phase of hair and villus production; Tianzhu white yaks older than seven years old should not be used for hair and villus production.
基金supported by the National Natural Science Foundation of China (30871795)the Earmarked Fund for Modern Agro-Industry Technology Research System,China (CARS-43-16)the Guangdong Provincial Science and Technology Research Grant, China (2010B020306004)
文摘This study investigated whether competitive reduction of pathogenic bacteria growth in pond water alleviates lipopolysaccharide （LPS） contamination and improves geese production performances in the ＂goose-fish＂ production system, thereby providing the potential for an improved technique for ecological water fowl production. In the first experiment, 240 Magang goslings of 15-d age were randomly and equally allocated into 16 ＂yard and pond＂ pens using a 2-2 factorial design with 4 replications per treatment. In the 55-d experimental period, the goslings received 2 main treatments： supplementation of Bacillus subtilis spores in the feed and addition of photosynthetic bacteria （PSB） to the pond water. Both B. subtilis spores and PSB treatments significantly suppressed water counts of Gram-negative bacteria Escherichia coli, Salmonella and Shigella, and LPS concentrations in pond water and in gosling blood （P〈0.05）. As the result, the two treatments significantly improved gosling weight gain and carcass quality, marked by enhanced breast and leg muscle percentages and reduced subcutaneous fat proportions （P〈0.05）. Moreover, the improved effects of B. subtilis spores and PSB treatments were additive. In the second experiment, 1 160 adult geese were induced to start egg laying from May throughout the summer months. The geese were separated equally into control and experimental flocks to fit into 2 integration production units, with a density of 1 bird m-2 meter on pond water. Experimental flock geese were treated with B. subtilis spores in feed and PSB in the pond water for the duration of the study. Such treatment combination significantly depressed the growth of E. coli, Salmonella and Shigella in the pond water and reduced LPS concentrations both in pond water and in geese blood （P〈0.01）. As a result, egg fertility, fertile and set egg hatchabilities were all improved in the treated flock. Results from both growing goslings and breeding geese demonstrated that water bacteria pollution can be competitively reduced by supplementation with B. subtilis spores via the feed and addition of PSB in pond water, each of which reduces LPS contamination to geese and improves production performances. Micro- ecological agents such as B. subtilis spores and PSB improve water quality and provide a simple ecological technique for the ＂water fowl-fish＂ integrative production system.
文摘The present research was designed to study the association of polymorphism of natural resistance-associated macrophage proteinl （Nrampl） with some immune function and the production performance in Large White pig. The PCR-RFLP technique was applied to analyze the correlation between the polymorphisms of Nrampl gene and immune function [value of Polymorphonuclear Leukocytes （PMN） obtained by Nitroblue Tetrazolium （NBT） Reduction and effect of Cytotoxin in Monocyte] and production performance in 165 Large White pigs. The results showed that there was one Nde I restriction locus in Large White pig, and both values of PMN by NBT Reduction and effect of Cytotoxin in Monocyte in genotype BB were higher than those in genotype AB （P〈0.05）. Simultaneously, the weight of 180-day-old pigs with genotype BB was higher than that with genotype AB （P〈0.05）. The results indicated that there was a significant correlation between different genotypes of Nrampl gene and Immune function and production performance, and it can be regarded as a candidate gene of disease resistance. All these results provide valuable reference to further studies of pig disease resistance.
基金This work was supported by the National Natural Science Foundation of China(Grant No.42050104)the Science Foundation of SINOPEC Group(Grant No.P20030).
文摘A comprehensive and precise analysis of shale gas production performance is crucial for evaluating resource potential,designing a field development plan,and making investment decisions.However,quantitative analysis can be challenging because production performance is dominated by the complex interaction among a series of geological and engineering factors.In fact,each factor can be viewed as a player who makes cooperative contributions to the production payoff within the constraints of physical laws and models.Inspired by the idea,we propose a hybrid data-driven analysis framework in this study,where the contributions of dominant factors are quantitatively evaluated,the productions are precisely forecasted,and the development optimization suggestions are comprehensively generated.More specifically,game theory and machine learning models are coupled to determine the dominating geological and engineering factors.The Shapley value with definite physical meaning is employed to quantitatively measure the effects of individual factors.A multi-model-fused stacked model is trained for production forecast,which provides the basis for derivative-free optimization algorithms to optimize the development plan.The complete workflow is validated with actual production data collected from the Fuling shale gas field,Sichuan Basin,China.The validation results show that the proposed procedure can draw rigorous conclusions with quantified evidence and thereby provide specific and reliable suggestions for development plan optimization.Comparing with traditional and experience-based approaches,the hybrid data-driven procedure is advanced in terms of both efficiency and accuracy.
基金supported by China National Program on Key Basic Research Project (973 Program) (Grant No. 2006CB705805)National Key Scientific and Technological Project (Grant No. 2008ZX05009-004)
文摘For extra-low permeability reservoirs, with a permeability of about 0.3×10?3 μm2, fluid flow and production performance in cores were studied. A long core holder with a multi-location piezometric measurement was specially designed. An artificial long core, about 700 mm long and with a cross section of 45mm×45mm, was used. In the experiment, pressure distribution along the core can be measured in real time. Single phase flow in the core was investigated. Different modes of production in long cores were also simulated including natural depletion, water flooding, and advanced water flooding. Through physical simulation, flow parameters were collected and production characteristics in extra-low permeability cores were studied. From experimental results, it can be seen that fluid flow in extra-low permeability cores is different from that in high permeability cores. Transmission of pressure in extra-low permeability cores is very slow, and it needs a long time for the pressure to become stable. The distribution curve of pressure along the core is nonlinear and the production rate in extra-low permeability reservoirs decreases sharply. The development effects of different production modes in extra-low permeability cores were compared with one another. Among the production modes, advanced water flooding has much potential for effective development of extra-low permeability reservoirs. Natural depletion and conventional water flooding can also be used in early production periods. In addition, the countermeasures and some ideas especially for the potential development of extra-low permeability reservoirs are suggested.
基金Supported by"Pig-based Eco-friendly Feed Research and Demonstration"of Science and Technology Department in Hebei Province(11220422)Technology Research on Application of"Animal-derived Active Red Gold Protein Peptide"in Pig Breeding(16226601D)
文摘[ Objectives ] To study the effects of low-protein diets supplemented with amino acids on the production performance, carcass quality and input-output ratio of fattening pigs and growing-finishing pigs. [ Methods] Two studies were conducted on fattening pigs and growing pigs respectively. Pigs in two experimental groupswere fed with low-protein diets supplemented with amino acids and normal diets respectively, and the initial weight, final weight, feed consumption and car- cass index of the tested pigs were measured. [ Results] The average final weight of fattening pigs in test group was 2.4 kg lower than that in control group, while the difference was not significant （P 〉 0.05 ）. The average daily gain of fattening pigs in test group was 60 g lower than that in control group, indicating that low protein diets had a tendency to decrease the growth rate （P 〉 0.05 ）, and reduction of daily weight gain in low protein diet pigs reached 7.6%. The development of pigs in low protein diet group was poor, however, the difference was not significant. Carcass backfat thickness in low-protein diet group was slightly higher than that in control group, the difference was significant （ P 〈 0.05 ）. There was no significant difference in input-output ratio between low-protein diet group and control group. Finalweight of growing-finishing pigs in low-protein diet group was 3.22 % lower than that in control group, the average daily weight gainwas 6.91% lower than that in control group, feed intake in test group was 5.48% lower than that in control group, and difference between the two treatments was significant （P 〈 0.05 ）. Feed meat ratio in low-protein diet group improved, however, the difference was not significant（P 〉0.05）. [ Conclusions] Production performance of the pigs would be decreasedand the input-output ratio could not be improvedwhen the adding contents of crude protein in diets was reduced 3% -4%. Therefore, it is recommended that the crude protein level should be enough when pigs were fed with low-protein diets.
文摘[Objective]The paper was to investigate the mechanism of Bacillus coagulans preparation in improving production performance of laying hens in late period of laying.[Method]A total of 648 individuals of"Jingfen 1"laying hens(66 weeks of age)in late period of laying were randomly divided into four groups,six replicates each group,and each group had 27 individuals of laying hens.The laying hens in control group were fed with basal diet,and those in experimental groupsⅠ,Ⅱ and Ⅲ were fed with the basal diets added with 3.33×10^6,1×10^7,3.33×10^7 CFU/g B.coagulans,respectively.The pretrial lasted one week,and the formal test lasted eight weeks.[Result]Compared with the control group,the laying rate in group Ⅰ increased significantly,and the feed-gain ratio in experimental group Ⅱ decreased noticeably while the spleen index increased remarkably;the alkaline phosphatase activities and blood calcium content in experimental groups Ⅰ,Ⅱ and Ⅲ increased significantly(P<0.05),while the triglyceride content decreased remarkably(P<0.05);the urea content in experimental groups Ⅰ and Ⅱ decreased obviously(P<0.05).Adding B.coagulans significantly increased the specific activity of amylase,lipase and protease in various intestinal mucosa of small intestine(P<0.05);adding B.coagulans significantly increased the content of follicle-stimulating hormone(FSH)and estradiol(E2),and significantly increased the mRNA expression of follicle stimulating hormone receptor gene(FSHR).[Conclusion]B.coagulans preparation could significantly improve the production performance of laying hens in late period of laying;appropriately enhance the immune capacity of laying hens;improve the serum biochemical indicators;increase the activity of digestive enzymes in the small intestine;and promote the release of gonadal hormone and the mRNA expression of FSHR gene in the ovary.
文摘Twenty lactating cows of two to five parity having an average live weight of 290.00 to 330.00 kg and an average milk production of 4.54 kg/head/day to 4.66 kg/head/day were selected from the Central Cattle breeding Station and Dairy Farm. The four dietary treatment were： SlooTo （Straw 100： Triticale 0 as control）; $5oT5o （Straw 50： Triticale 50）; $25T75 （Straw 25： Triticale 75） and SoTloo （Straw 0： Triticale 100）. It was observed that the roughage dry matter intake （DMI） （2.61 ~ 0.07 kg） in percent live weight was significantly （P 〈 0.05） higher in $25T75 and the lowest （1.76 ~ 0.018 kg） in the control group （SlooTo） and the differences were significant among the dietary treatments except $5oT5o and SoTloo. The total DMI was significantly （P 〈 0.05） higher in SoT^oo （13.36 i 0.13 kg） followed by $25T75, $5oT5o and SlooTo, respectively. The digestibility of crude protein （CP） was slightly higher in $25T75 （75.48 ~ 0.96） compared to SoTtoo （75.31 ~ 1.45） and the difference was non-significant （P 〉 0.05）. Milk production was significantly （P 〈 0.05） the highest in $5oT5o and the lowest in SlooTo followed by SoTloo, $25T75, respectively. The percent increased in milk yield was also the highest in $5oT5o （67.68%） and the lowest in SlooTo （28.85%）. The 4% fat corrected milk was also significantly （P 〈 0.05） higher in $5oT5o followed by SoTloo, $25T75 and SlooTo, respectively. Therefore, it can be concluded that triticale and straw at a ratio of 50：50 may be fed for better production performance of dairy cows.
基金Supported by National Basic Research Program(2014CB138704)National Natural Science Foundation of China(31302023)
文摘Production performance of four forage legumes species of Medicago sativa,Onobrychis viciifolia,Lotus corniculatus and Galega officinalis were determined,including plant height,above-ground biomass per unit area,tillers per unit area,fertile tillers per unit area,shoot /leaf ratio and fresh /dry matter weight ratio,and the distribution characteristics of their root systems in 0- 100 cm soil layers with 10 cm interval were studied. Results showed that the average aboveground fresh biomass(4 a and 5 a) of four forage legumes species successively were L. corniculatus 】 M. sativa 】 O. viciifolia 】 G. officinalis. The average plant heights in two years successively were O. viciifolia 】 M. sativa 】 G. officinalis 】 L. corniculatus. Tillers per unit area of four forage legume species in two years successively were M. sativa 】 L. corniculatus 】 O. viciifolia 】 G. officinalis. Fertile tillers per unit area in two years were O. viciifolia 】 M. sativa 】 L. corniculatus 】 G. officinalis. Average shoot /leaf ratio in two years were G. officinalis 】 M. sativa 】 O. viciifolia 】 L. corniculatus. Average moisture contents of four forage legume species in two years successively were G. officinalis 】 L. corniculatus 】 M. sativa = O. viciifolia. The distribution characteristics of root systems of four forage legumes species in 0- 100 cm soil layers were as follows: the root weights of M. sativa in 0- 40 cm soil layers accounted for about 98. 3% of total root weight,that of O. viciifolia in 0- 30 cm soil layers was 85. 8%,that of L. corniculatus in 0- 10 cm soil layers was 80%,and that of G. officinalis in 0- 40 cm soil layers was 81. 4%. The results suggested that L. corniculatus was suited to plant in slighter degraded pasture to control water and soil erosion in early stage,G. officinalis with strong lateral roots was adapted to degraded grassland in the Loess Plateau where soil nutrient was poor,while O. viciifolia and M. sativa with potentially strong main root were fit for water and soil conservation in the losses plateau for long term.
基金Natural Science Foundation of Qinghai Province(2020-ZJ-957Q)Qinghai University for Nationalities 2020 High-level Talent(PhD)Project(2020XJG14)。
文摘Domestic and foreign researches on triticale mainly focus on hereditary traits and excellent characteristics,but there are few reports on triticale yield and quality in the severe cold pastoral areas of Gansu and Qinghai.In this study,Gannong 2 triticale cultivars have been bred and planted in typical ecological areas according to the characteristics of different ecological regions.By studying the relationship between quality traits and various ecological factors,the effects of different ecological factors on the quality of Triticale hay have been clarified,which provides a reasonable basis for future triticale breeding and large-scale and targeted planting layout.The production performance and nutritional qualities of Triticale Trial in Maqu County,Gansu Province and Gannong No.2 in Dulan County,Qinghai Province are obviously superior to other pilot sites.Through reasonable fertilization,the production performance and nutritional quality of triticale are the best.Triticale production performance is significantly related to climatic factors in different pilots.The most suitable planting area for Gannong 2 is Maqu County,Gansu Province.
文摘The aim of this study was to investigate the effects of </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;"> and its fermentation products on performance, blood hormone levels and rumen floral composition in peripartum dairy cows. Sixty perinatal cows were selected and allocated to two groups according to parity and expected date of delivery. Each group was supplemented with </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;"> and its fermentation product 0 or 100 g. The results showed that </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;"> and its fermentation products could significantly increase the feed intake of peripartum dairy cows (P < 0.01), increase the lactose content after 21 days postpartum (P < 0.01), and tend to increase milk production (P = 0.052). There was no significant effect on other milk components, the apparent digestibility of nutrients. There was a tendency to increase milk production and reduce the number of somatic cells in milk;increase blood levels of glucagon (P < 0.01) and </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-hydroxybutyrate (P = 0.01), reducing the insulin content (P = 0.02).</span></span><span style="font-family:""> </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:""><span style="font-family:Verdana;"> reduced the abundance of rumen microbes in peripartum dairy cows but had no effect on rumen microbial diversity. Compared with the control group, the supplemented group showed reductions in the abundance of genera </span><i><span style="font-family:Verdana;">Bacillus</span></i><span style="font-family:Verdana;"> (P = 0.03), </span><i><span style="font-family:Verdana;">Butyrivibrio</span></i><span style="font-family:Verdana;"> (P = 0.01), </span><i><span style="font-family:Verdana;">Denitrobacterium</span></i><span style="font-family:Verdana;"> (P = 0.01), and </span><i><span style="font-family:Verdana;">Mogibacterium</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Porphyromonas</span></i><span style="font-family:Verdana;"> (P = 0.05), </span><i><span style="font-family:Verdana;">Saccharofermentans</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Sphaerochaeta</span></i><span style="font-family:Verdana;"> (P = 0.02), </span><i><span style="font-family:Verdana;">Streptococcus</span></i><span style="font-family:Verdana;"> (P = 0.04) and other genera. There were significant increase in the content of </span><i><span style="font-family:Verdana;">Acidaminococcus</span></i><span style="font-family:Verdana;"> (P = 0.03), </span><i><span style="font-family:Verdana;">Allisonella</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Bulleidia</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Corynebacterium</span></i><span style="font-family:Verdana;"> (P = 0.01), </span><i><span style="font-family:Verdana;">Dialister</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Faecalibacterium</span></i><span style="font-family:Verdana;"> (P = 0.02), </span><i><span style="font-family:Verdana;">Faekalitalea</span></i><span style="font-family:Verdana;"> (P = 0.03), </span><i><span style="font-family:Verdana;">Fibrobacter</span></i><span style="font-family:Verdana;"> (P = 0.04), </span><i><span style="font-family:Verdana;">Flavobacterium</span></i><span style="font-family:Verdana;"> (P = 0.03), </span><i><span style="font-family:Verdana;">Kandleria</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Paraprevotella</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Pyramidobacter</span></i><span style="font-family:Verdana;"> (P = 0.05), </span><i><span style="font-family:Verdana;">Roseburia</span></i><span style="font-family:Verdana;"> (P < 0.01), </span><i><span style="font-family:Verdana;">Succinivibrio</span></i><span style="font-family:Verdana;"> (P < 0.01) and other genera.</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">The main metabolic pathways such as tryptophan metabolism and steroid hormone biosynthesis in perinatal dairy cows were determined for </span><i><span style="font-family:Verdana;">Saccharomyces cerevisiae</span></i><span style="font-family:Verdana;"> and its fermentation products.
基金Supported by Modern Agricultural Industry Technology System Construction Special Fund(nycytx-41-2B)Social Development Project of Yangzhou(yz2010080)
文摘[Objective]In order to research on effect of different content of cottonseed meals on production performance and egg quality of Hisex laying hens. [Methods]120 Hisex laying hens of 37 weeks old are chosen,randomly divided into four groups and three repetitions are set in each group,there are 10 hens in each repetition. Group I is the control group,II,III and IV are experimental groups. Cottonseed meal contents are respectively 5%,10% and 15%,with test cycle of 10 weeks,effects of different cottonseed meal dosages on Hisex laying hens production performance and egg quality are observed. [Results]When the diet is added with 5% to 15% of cottonseed meal,the average laying rate,average egg weight and feed-gain ratio all show downward trends when compared with that of the control group,but with no significant difference（ P 〉 0. 05）; eggshell strength,eggshell thickness,Haugh unit,egg shape index all show no significant difference（ P 〉0. 05）,with the increasement of cottonseed meal,the color of egg yolk got brighter,egg yolk color of 15% added group increased by 12%,show a significant difference with that of control group（ P 〈0. 05）. [Conclusion]When the feed was added with 15% cottonseed meals,it has an unconspicuous effect on laying performance and egg quality of Hisex laying hens,but whether it had an effect on animal health and food safety or not,a further systematic research is needed.
基金supported by the National Natural Science Foundation of China“Basic Research on Reservoir Anhydration and Gas Flow Capacity Improvement in Tight Gas Reservoir”(No.:51534006)the Scientific Research Starting Project of Southwest Petroleum University(No.:2015QHZ003)the Development Fund for Young Scholars of Southwest Petroleum University(No.:201599010088).
文摘Volume fracturing technology has been widely applied in the development of coalbed methane(CBM)reservoirs.As for the stimulated reservoir volume(SRV)created by volume fracturing,the seepage laws of fluids are described more accurately and rationally in the rectangular composite model than in the traditional radial composite model.However,the rectangular composite model considering SRV cannot be solved using the analytical or semi-analytical function method,and its solution from the linear flow model has larger errors.In view of this,SRVareas of CBM reservoirs were described by means of dual-medium model in this paper.The complex CBM migration mechanisms were investigated comprehensively,including adsorption,desorption,diffusion and seepage.A well testing model for rectangular composite fracturing wells in CBM reservoirs based on unsteady-state diffusion was built and solved using the boundary element method combined with Laplace transformation,Stehfest numerical inversion and computer programming technology.Thus,production performance laws of CBM reservoirs were clarified.The flow regimes of typical well testing curves were divided and the effects on change laws of production performance from the boundary size of gas reservoirs,permeability of volume fractured areas,adsorption gas content,reservoir permeability and SRV size were analyzed.Eventually,CBM reservoirs after the volume fracturing stimulation were described more accurately and rationally.This study provides a theoretical basis for a better understanding of the CBM migration laws and an approach to evaluating and developing CBM reservoirs efficiently and rationally.
基金Supported by Core Pure Population Breeding and Industry Demonstration Base Construction of Changshun Green-shell Layer(QNYZ[2011]027)Association Study of PRL Gene and PRLR Gene Polymorphisms of Changshun Greenshell Layer with Egg Production Traits(QKHJ[2011]2174)
文摘To explore the effect of different additive combinations on double-low rapeseed cake （meal） utilization and layer production performance, we randomly divided 756 Roman brown shell layers around 50 weeks age into seven groups to detect production performance, of which group 1 was control group supplied with basic diet （added with 9% double-low rapeseed cake）, while groups 2 -7 were experimental groups added with Chinese herbal medicine, enzyme preparation, pro- biotics and peptide antibiotics in basic diet. The results showed that group 4 added with Chinese herbal medicine ＋ enzyme preparation ＋ peptide antibiotics re- ceived the best effect, resulting in significantly increased laying rate （70.50%, P 〈 0.05 ）, significantly reduced feed-egg ratio （2.46, P 〈 0.05 ）, and extremely increased egg Haugh unit （P 〈0.01 ）. This indicated that adding combination of Chinese herbal medicine ＋ enzyme preparation ＋ peptide antibiotics in layer bas- ic diet could improve egg production performance and egg quality of layers.
文摘Using a multi-input multi-output production technology and survey data from Jinzhai County, western Anhui Province, China, the author first measured the production performance of rural households their efficiency, economy of scale, and productivity during 19781997, and then related the measured production performance with institutional change, market access, and other factors. Preliminary results show that: 1) performance differs a great deal across households and over time; 2) institutional changes and market accessibility have played a major role in improving performance; 3) depending on the specific resources, their effects are variable.
基金Supported by the National Science and Technology Support Program Project(2011BAD47B04)
文摘In this study,the effects of two types of premixed materials with different combinations of trace elements on the production performance and antioxidant capacity of simmental beef cattle were examined.Fifteen healthy simmental beef cattle of similar weight(approximately 330 kg),the same age(12 months),without castration,and a good physique were divided into three groups,with five beef cattle in each group.Food of Group Ⅰ beef cattle was supplemented with a commercially marketed 5% compound trace element premixture for fine beef cattle.Food of Group Ⅱ beef cattle was supplemented with a 5% compound microelement premixture for beef cattle that was designed to address local nutrient deficiencies and surpluses.In the blank control group,the beef cattle were not fed a premixture.The pretest period was 15 days,and the test period was divided into prefattening(45 days)and postfattening(45 days)stages.Body weight and body size indices were recorded at 1,2 and 3 months,and blood samples were collected regularly.In Group Ⅰ,the daily weight gain increased significantly by 15.7% compared with that of the control group.The largest daily weight gain was in Group Ⅱ,which increased by 31.6% compared with that in the control.During the test period of 90 days,the body size indices of the three different groups increased in different months,with significant increases in the indices for both test groups compared with those of the control.In Group Ⅰ,the activity of CP,the total activity of SOD and Cu-Zn-SOD increased significantly(p<0.05)compared with those in the control group,with a highly significant increase observed in GSH-PX activity(p<0.01).In Group Ⅱ,the increases in the activity of CP and the total activity of SOD and Cu-Zn-SOD were highly significant compared with those in the control group(p<0.01).In addition,a significant increase was observed in GSH-PX activity(p<0.05).Based on pretest results,the concentrations of Cu,Zn,Mo,Mn,Se and Co in the blood of experimental beef cattle were lower than those of the normal range.After feeding for 90 days,the concentrations of Cu,Zn,Mo,Mn,Se and Co in the blood of Groups Ⅰ and Ⅱ were significantly higher than those in the control group(p<0.05).The concentrations of elements in the blood of Group Ⅱ were close to the appropriate levels.Thus,the effects of the specifically designed compound microelement premixture on the prevention of nutrient imbalances and control of beef cattle nutrition metabolism and the production of fattened beef cattle were significant.
