Background： The goal of this study was to compare the antagonism of elevated dietary Cu （250 mg/kg） from CuS04 on three different Zn sources （ZnS04. H20; [Zn bis（-2-hydroxy-4-（methylthio）butanoic acid）], Zn（H...Background： The goal of this study was to compare the antagonism of elevated dietary Cu （250 mg/kg） from CuS04 on three different Zn sources （ZnS04. H20; [Zn bis（-2-hydroxy-4-（methylthio）butanoic acid）], Zn（HMTBa）2 a chelated Zn methionine hydroxy analogue; and Zn-Methionine）, as measured using multiple indices of animal performance in ROSS 308 broilers. Methods： Three experiments were conducted in broiler chicks fed a semi-purified diet. All birds were fed a Zn-deficient diet （8.5 mg/kg diet） for 1 wk, and then provided with the experimental diets for 2 wks. Results： Experiment 1 was a 2 x 2 factorial design with two levels of Cu （8 vs. 250 mg/kg diet from CuSO4） and two Zn sources at 30 mg/kg [ZnSO4. H20 vs. Zn（HMTBa）2]. Elevated Cu impaired growth performance only in birds fed ZnSO4. Compared to ZnSO4. H20, Zn（HMTBa）2 improved feed intake （12 %; P 〈 0.001） and weight gain （12 %, P 〈 0.001） and the benefits were more pronounced in the presence of 250 mg/kg diet Cu. Experiment 2 was a dose titration of ZnSO4- H20 and Zn（HMTBa）2 at 30, 4,5, 60, and 75 mg/kg diet in the presence of 250 mg/kg CuSO4. Feed：gain was decreased and tibia Zn was increased with increasing Zn levels from 30 to 75 mg/kg. Birds fed Zn（HMTBa）2 consumed more food and gained more weight compared to birds fed ZnSO4, especially at lower supplementation levels （30 and 45 mg/kg; interaction P 〈 0,05）. Experiment 3 compared two organic Zn sources （Zn（HMTBa）2 vs. Zn-Methionine） at 30 mg/kg with or without 250 mg/kg CuSO4. No interactions were observed between Zn sources and Cu levels on performance or tissue mineral concentrations. High dietary Cu decreased weight gain （P 〈 0.01）. Tibia Cu and liver Cu were significantly increased with 250 mg/kg dietary Cu supplementation （P 〈 0.01）. No difference was observed between the two Zn sources. Conclusions： Dietary 250 mg/kg Cu significantly impaired feed intake and weight gain in birds fed ZnSO4. H20, but had less impact in birds fed Zn（HMTBa）2. No difference was observed between the two organic zinc sources These results are consistent with the hypothesis that chelated organic Zn is better utilized than inorganic zinc in the presence of elevated Cu.展开更多
Background:Over the past years,antibiotic growth promoter had been restricted in animal husbandry production in many countries because of antimicrobial resistance and foodborne antibiotic residues.However,the problems...Background:Over the past years,antibiotic growth promoter had been restricted in animal husbandry production in many countries because of antimicrobial resistance and foodborne antibiotic residues.However,the problems of poor intestinal health and low growth efficiency of piglets have not been solved completely in an antibiotic-free diet,and it is urgent to explore alternatives to antimicrobial growth promoters.Methods:Here,a total of 532 weaned pigs were assigned to one of 4 treatments,the low amino acid(AA)level diet(d 1 to d 14 is 1.35%,d 15 to d 42 is 1.25%)(Low AA),the low AA level diet supplementation with a carvacrol-thymol blend(50 mg carvacrol and 50 mg thymol/kg of diet)(CB)(Low AA+CB),the high AA level diet(d 1 to d 14 is 1.50%,d 15 to d 42 is 1.40%)(High AA),and the high AA level diet supplementation with a CB(High AA+CB),respectively.Then we measured growth performance and intestinal health indicators of weaned pigs.Results:Results showed that high AA level significantly reduced plasma urea nitrogen,plasma Interleukin-6(IL-6)and fecal lipocalin-2 contents(P<0.05),significantly increased the relative abundance of fecal Lactobacillus and Enterococcus,and had a trend to increase the fecal secretory immunoglobulin A(sIgA)and mucin 2(MUC 2)contents(P<0.05)in piglets,thereby alleviating the diarrhea of piglets and reducing the feed conversion ratio(FCR)of piglets during d 1~14 after weaning.Dietary supplementation with CB significantly increased the activity of plasma antioxidant enzymes T-SOD and GSH-px(P<0.05),while significantly reduced plasma malondialdehyde(MDA),plasma interleukin-1β(IL-1β),plasma endotoxin and D-lactic acid contents(P<0.05).Meanwhile,CB significantly decreased fecal lipocalin-2 contents and the abundance of fecal Escherichia coli(P<0.05).Thus,we hypothesis that dietary supplementation with CB significantly increased the average daily gain(ADG)of piglets(P<0.05)during d 1~14 after weaning through promoting intestinal health.Conclusion:These results suggest that high AA level and dietary supplementation with CB improved the growth performance of weaned pigs in an antibiotic-free diet by improving AA metabolism and intestinal antioxidant capacity.展开更多
Background： This study was designed to evaluate the efficacy of DL-selenomethionine （DL^SeMet） supplementation on growth performance, antioxidant status, plasma selenium （Se） concentration, and immune function of...Background： This study was designed to evaluate the efficacy of DL-selenomethionine （DL^SeMet） supplementation on growth performance, antioxidant status, plasma selenium （Se） concentration, and immune function of weaning pigs. 216 weaning pigs were randomly allocated to 6 treatments with 6 replicates each according to a complete randomized block design. Each replicate had six pigs. Diet of group one was corn-soybean basal diet without any additional Se supplement. Group 2 was supplemented with 0.3 mg/kg of Se from sodium selenite. Groups 3-6 were supplemented with 0.1, 0.3, 0.5, and 0.7 mg/kg of Se from DL-SeMet, respectively. The trial lasted for 42 days. Results： Pigs supplemented with 0.3 and 0.7 mg/kg DL-SeMet obtained better feed gain ratio （P 〈 0.05）. The best antioxidant ability （serum, liver, and muscle） was shown in 0.1-0.3 mg/kg DL-SeMet groups （P〈 0.05）. The plasma Se concentration increased as the dietary DL-SeMet level elevated. The immunity among groups was not affected. Conclusions： DL-SeMet supplementation in the diet significantly improved the growth performance, antioxidant ability and plasma Se content of weaning pigs. DL-SeMet can replace sodium selenite in the diet of weaning pigs.展开更多
Background: The use of feed grade amino acids can reduce the cost of lactation feed. With changing genetics,increasing feed costs, and higher number of pigs weaned with heavier wean weights further evaluation of highe...Background: The use of feed grade amino acids can reduce the cost of lactation feed. With changing genetics,increasing feed costs, and higher number of pigs weaned with heavier wean weights further evaluation of higher inclusion levels of feed-grade amino acid in lactation diets than previously published is warranted. Two experiments(Exp.) were conducted to determine the optimal inclusion level of L-lysine HCl to be included in swine lactation diets while digestible lysine levels remain constant across dietary treatments and allowing feed grade amino acids to be added to the diet to maintain dietary ratios relative to lysine to maximize litter growth rate and sow reproductive performance. Furthermore, the studies were to evaluate minimal amino acid ratios relative to lysine that allows for optimal litter growth rate and sow reproductive performance.Results: Exp. 1: Increasing L-lysine HCl resulted in similar gilt feed intake, litter, and reproductive performance.Average litter gain from birth to weaning was 2.51, 2.49, 2.59, 2.43, and 2.65 kg/d when gilts were fed 0.00, 0.075,0.150, 0.225, and 0.30% L-lysine HCl, respectively. Exp. 2: The average litter gain from birth to weaning was 2.68,2.73, 2.67, 2.70, and 2.64 kg/d(P < 0.70) when sows were fed 0.1, 0.2, 0.3, 0.4, and 0.4% L-lysine HCl plus valine,respectively. No other differences among dietary treatments were observed.Conclusions: Collectively, these studies demonstrate corn-soybean meal based lactation diets formulated with a constant SID lysine content for all parities containing up to 0.40% L-lysine HCl with only supplemental feed grade threonine and a methionine source have no detrimental effect on litter growth rate and subsequent total born.展开更多
To investigate the antibacterial activity of commercial organic acid Activate WD （WD）, the minimal inhibitory concentration （MIC） and minimal bactericidal concentration （MBC） of WD against Staphylococcus aureus,...To investigate the antibacterial activity of commercial organic acid Activate WD （WD）, the minimal inhibitory concentration （MIC） and minimal bactericidal concentration （MBC） of WD against Staphylococcus aureus, Escherichia coli, Salmonella pullorum, and Campylobacter jejuni were determined by double broth dilution method. Bacteria were added in a mixture of water and commercial broiler feed adjusted by WD into pH 3.0, 4.0, and 5.0; the survival of bacteria was determined by a direct plate count method at 0, 0.5, 1, 4, 8, and 24 h after being mixed to test the bactericidal potential of WD. The results showed that the MIC of WD against four bacteria was 0.3125%, and the MBC was 0.625%. At pH 3.0, bacteria could not survive. Campylobacter jejuni died after 4 h of incubation at pH 4.0, 5.0, whereas for other three bacteria, the bacterium numbers were below detection limits until 8 h of incubation. In conclusion, WD had significant antibacterial activity, and could be used on farms to prevent cross-infection via rearing water.展开更多
Proximate nutrient composition (crude protein, non-fiber carbohydrates, crude fiber, and ash), fiber fractions (neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin), and both macro (calcium (Ca), phospho...Proximate nutrient composition (crude protein, non-fiber carbohydrates, crude fiber, and ash), fiber fractions (neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin), and both macro (calcium (Ca), phosphorus (P), magnesium (Mg), potassium (K), sodium (Na), and sulfur (S)) and trace (copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), and zinc (Zn)) mineral profiles were quantified in mixed pasture samples collected during the wet (n = 8) and dry (n = 15) seasons in north central Uganda. Metabolizable and Net Energy values for dairy production were estimated based on standard calculations, and samples were compared seasonally. Crude fat (p = 0.05) and lignin (p = 0.01) values were lower in the dry compared with the wet season, linked with reduced plant growth. Crude protein (13.0% of dry matter (DM)), fiber fractions, and calculated energy content did not vary seasonally in this data set, and reflected chemical components of a grass-dominated system that appeared energetically limiting for production livestock. Mineral constituents varied more dramatically by season, with Ca, Mg, Cu, and Mn lower (all 0.05) and K higher in the dry season. Sodium was deficient in these pastures, whereas Ca, P, Mg, S, Cu, and Zn concentrations may have been only marginally sufficient, particularly to meet needs for lactation, dependent on season. These limited data suggest that a high-energy mineral supplement may prove beneficial in meeting nutritional and production needs of multiple grazing ruminant species in this region, particularly during dry seasons.展开更多
This experiment evaluated the impacts of essential oils(EO)and protease(PRO),independently or in combination,on growth performance,antioxidation,inflammation and intestinal function of weaned pigs.One hundred and sixt...This experiment evaluated the impacts of essential oils(EO)and protease(PRO),independently or in combination,on growth performance,antioxidation,inflammation and intestinal function of weaned pigs.One hundred and sixty weaned pigs(21 d of age,BW of 6.74±0.20 kg)were randomly divided into 4 treatments with 8 replicate pens of 5 pigs per pen.Dietary treatments included the following:1)control diet(CON),2)CON with 300 mg/kg essential oils(EO),3)CON with 500 mg/kg protease(PRO),4)CON with 300 mg/kg essential oil and 500 mg/kg protease(EO + PRO).On d 8,one pig from each penwas selected for sampling.The remaining pigs were fed for an additional week and growth performance was monitored during this period.Dietary treatments had no marked effects(P>0.05)on the growth performance of pigs.However,pigs receiving EO diet had higher(P<0.05)serumglutathione peroxidase(GSH-Px)activity,and tended to decrease(P=0.063)serum concentration of tumor necrosis factor-a(TNF-a).In addition,pigs receiving EO diet had higher(P<0.05)abundances of phylum Actinobacteria,and genera Bifidobacterium,and lower(P<0.05)phylum Bacteroidetes and genera Alloprevotella in colonic digesta.Pigs receiving PRO diet decreased(P<0.05)the serum concentration of malondialdehyde(MDA)and diamine oxidase activity,increased(P<0.05)the villus height and the ratio of villus height to crypt depth in duodenum,increased sucrase activity in jejunal mucosa,and also increased the abundance of phylum Actinobacteria in colonic digesta.Furthermore,the synergistic effects of EO and PROwas observed(P<0.05)for pigs with decreasing serum TNF-a concentration and increasing serum GSH-Px activity.Collectively,the results indicated that dietary supplementation of EO and PRO had no significant effects on growth performance of weaned pigs.EO diet appeared to improve antioxidant activity and intestinal microbiota,while PRO diet improved intestinal morphology and digestive enzyme activity,and there was a synergistic effect of EO and PRO on reducing inflammatory parameters in weaned pigs.展开更多
The goal of this review article,based on a systematic literature search,is to critically assess the state of knowledge and experimental methodologies used to delineate the conversion and metabolism of the 2 methionine...The goal of this review article,based on a systematic literature search,is to critically assess the state of knowledge and experimental methodologies used to delineate the conversion and metabolism of the 2 methionine(Met)sources DL-methionine(DL-Met)and DL-2-hydroxy-4-(methylthio)butanoic acid(HMTBa).The difference in the chemical structures of HMTBa and DL-Met indicates that these molecules are absorbed and metabolized differently in animals.This review explores the methodologies used to describe the 2-step enzymatic conversion of the 3 enantiomers(D-HMTBa,L-HMTBa and D-Met)to L-Met,as well as the site of conversion at the organ and tissue levels.Extensive work was published documenting the conversion of HMTBa and D-Met into L-Met and,consequently,the incorporation into protein using a variety of in vitro techniques,such as tissue homogenates,cell lines,primary cell lines,and everted gut sacs of individual tissues.These studies illustrated the role of the liver,kidney,and intestine in the con-version of Met precursors into L-Met.A combination of in vivo studies using stable isotopes and infusions provided evidence of the wide conversion of HMTBa to L-Met by all tissues and how some tissues are net users of HMTBa,whereas others are net secreters of L-Met derived from HMTBa.Conversion of D-Met to L-Met in organs other than the liver and kidney is poorly documented.The methodology cited in the literature to determine conversion efficiency ranged from measurements of urinary,fecal,and respiratory excretion to plasma concentration and tissue incorporation of isotopes after intraperitoneal and oral in-fusions.Differences observed between these methodologies reflect differences in the metabolism of Met sources rather than differences in conversion efficiency.The factors affecting conversion efficiency are explored in this paper and are mostly associated with extreme dietary conditions,such as noncommercial crystalline diets that are very deficient in total sulfur amino acids with respect to requirements.Impli-cations in the diversion of the 2 Met sources toward transsulfuration over transmethylation pathways are discussed.The strengths and weaknesses of some methodologies used are discussed in this review.From this review,it can be concluded that due to the inherent differences in conversion and metabolism of the 2 Met sources,the experimental methodologies(e.g.,selecting different organs at different time points or using diets severely deficient in Met and cysteine)can impact the conclusions of the study and may explain the apparent divergences of conclusion found in the literature.It is recommended when con-ducting studies or reviewing the literature to properly select the experimental models that allow for differences in how the 2 Met precursors are converted to L-Met and metabolized by the animal to enable a proper comparison of their bioefficacy.展开更多
This literature review evaluates the absorption of methionine (Met) sources such as 2-hydroxy-4-methylthiobutyric acid (HMTBa), its calcium salts (HMTBa-Ca), and DL-methionine (DL-Met) by focusing on the state of know...This literature review evaluates the absorption of methionine (Met) sources such as 2-hydroxy-4-methylthiobutyric acid (HMTBa), its calcium salts (HMTBa-Ca), and DL-methionine (DL-Met) by focusing on the state of knowledge regarding the absorption mechanism, experimental methodology, and factors affecting their absorption. The 2 Met sources differ in mechanism and site of absorption due to differences in their chemical characteristics and enzymatic conversion. This review addresses diffusion- and transport-mediated absorption systems for amino acids and carboxylic compounds, best elucidated by in vitro, ex vivo, and in vivo experimental models. Opportunities and limitations in the use of radioisotopes to depict absorption sites as well as host and microbial metabolism are described. Physiological and environmental conditions that lead to changes in gut absorptive capacity and the impact of Met source absorption are also evaluated. This review concludes that any comparison between HMTBa and DL-Met should consider their different behaviors during the absorption phase. Hence, the chemical characteristics of these 2 molecules entail different absorption sites and mechanisms, from passive absorption in the case of HMTBa and HMTBa-Ca to active transporters for DL-Met, HMTBa, and HMTBa-Ca. In addition, the different conversion modes of these 2 molecules further differentiate their absorption modes. Considering these important differences, it is easier to understand the apparent divergence between the conclusions of existing publications. When comparing these 2 molecules, it is recommended to properly adapt to the conditions under which the absorption of Met sources is evaluated.展开更多
Our publication on absorption of methionine sources(Becquet et al.,2023a)is a thorough analysis of 129 references dealing with absorption of sources of methionine,with the objective to critically evaluate the methodol...Our publication on absorption of methionine sources(Becquet et al.,2023a)is a thorough analysis of 129 references dealing with absorption of sources of methionine,with the objective to critically evaluate the methodologies used and their impact on the conclusions of the studies.As the focus of our publicationwas on the evaluation of absorption,efficacy studies and reports not having information on absorption were not considered(Elwert et al.,2008;Rychen et al.,2008).展开更多
文摘Background： The goal of this study was to compare the antagonism of elevated dietary Cu （250 mg/kg） from CuS04 on three different Zn sources （ZnS04. H20; [Zn bis（-2-hydroxy-4-（methylthio）butanoic acid）], Zn（HMTBa）2 a chelated Zn methionine hydroxy analogue; and Zn-Methionine）, as measured using multiple indices of animal performance in ROSS 308 broilers. Methods： Three experiments were conducted in broiler chicks fed a semi-purified diet. All birds were fed a Zn-deficient diet （8.5 mg/kg diet） for 1 wk, and then provided with the experimental diets for 2 wks. Results： Experiment 1 was a 2 x 2 factorial design with two levels of Cu （8 vs. 250 mg/kg diet from CuSO4） and two Zn sources at 30 mg/kg [ZnSO4. H20 vs. Zn（HMTBa）2]. Elevated Cu impaired growth performance only in birds fed ZnSO4. Compared to ZnSO4. H20, Zn（HMTBa）2 improved feed intake （12 %; P 〈 0.001） and weight gain （12 %, P 〈 0.001） and the benefits were more pronounced in the presence of 250 mg/kg diet Cu. Experiment 2 was a dose titration of ZnSO4- H20 and Zn（HMTBa）2 at 30, 4,5, 60, and 75 mg/kg diet in the presence of 250 mg/kg CuSO4. Feed：gain was decreased and tibia Zn was increased with increasing Zn levels from 30 to 75 mg/kg. Birds fed Zn（HMTBa）2 consumed more food and gained more weight compared to birds fed ZnSO4, especially at lower supplementation levels （30 and 45 mg/kg; interaction P 〈 0,05）. Experiment 3 compared two organic Zn sources （Zn（HMTBa）2 vs. Zn-Methionine） at 30 mg/kg with or without 250 mg/kg CuSO4. No interactions were observed between Zn sources and Cu levels on performance or tissue mineral concentrations. High dietary Cu decreased weight gain （P 〈 0.01）. Tibia Cu and liver Cu were significantly increased with 250 mg/kg dietary Cu supplementation （P 〈 0.01）. No difference was observed between the two Zn sources. Conclusions： Dietary 250 mg/kg Cu significantly impaired feed intake and weight gain in birds fed ZnSO4. H20, but had less impact in birds fed Zn（HMTBa）2. No difference was observed between the two organic zinc sources These results are consistent with the hypothesis that chelated organic Zn is better utilized than inorganic zinc in the presence of elevated Cu.
基金supported by Hubei Province Science and Technology Innovation Major Project(2019ABA081,2021BBA083)China Agriculture Research System of MOF and MARA.
文摘Background:Over the past years,antibiotic growth promoter had been restricted in animal husbandry production in many countries because of antimicrobial resistance and foodborne antibiotic residues.However,the problems of poor intestinal health and low growth efficiency of piglets have not been solved completely in an antibiotic-free diet,and it is urgent to explore alternatives to antimicrobial growth promoters.Methods:Here,a total of 532 weaned pigs were assigned to one of 4 treatments,the low amino acid(AA)level diet(d 1 to d 14 is 1.35%,d 15 to d 42 is 1.25%)(Low AA),the low AA level diet supplementation with a carvacrol-thymol blend(50 mg carvacrol and 50 mg thymol/kg of diet)(CB)(Low AA+CB),the high AA level diet(d 1 to d 14 is 1.50%,d 15 to d 42 is 1.40%)(High AA),and the high AA level diet supplementation with a CB(High AA+CB),respectively.Then we measured growth performance and intestinal health indicators of weaned pigs.Results:Results showed that high AA level significantly reduced plasma urea nitrogen,plasma Interleukin-6(IL-6)and fecal lipocalin-2 contents(P<0.05),significantly increased the relative abundance of fecal Lactobacillus and Enterococcus,and had a trend to increase the fecal secretory immunoglobulin A(sIgA)and mucin 2(MUC 2)contents(P<0.05)in piglets,thereby alleviating the diarrhea of piglets and reducing the feed conversion ratio(FCR)of piglets during d 1~14 after weaning.Dietary supplementation with CB significantly increased the activity of plasma antioxidant enzymes T-SOD and GSH-px(P<0.05),while significantly reduced plasma malondialdehyde(MDA),plasma interleukin-1β(IL-1β),plasma endotoxin and D-lactic acid contents(P<0.05).Meanwhile,CB significantly decreased fecal lipocalin-2 contents and the abundance of fecal Escherichia coli(P<0.05).Thus,we hypothesis that dietary supplementation with CB significantly increased the average daily gain(ADG)of piglets(P<0.05)during d 1~14 after weaning through promoting intestinal health.Conclusion:These results suggest that high AA level and dietary supplementation with CB improved the growth performance of weaned pigs in an antibiotic-free diet by improving AA metabolism and intestinal antioxidant capacity.
基金supported by NOVUS Intl.(MO.USA)The authors are grateful to the company for supplying fund and DL-SeMet samples
文摘Background： This study was designed to evaluate the efficacy of DL-selenomethionine （DL^SeMet） supplementation on growth performance, antioxidant status, plasma selenium （Se） concentration, and immune function of weaning pigs. 216 weaning pigs were randomly allocated to 6 treatments with 6 replicates each according to a complete randomized block design. Each replicate had six pigs. Diet of group one was corn-soybean basal diet without any additional Se supplement. Group 2 was supplemented with 0.3 mg/kg of Se from sodium selenite. Groups 3-6 were supplemented with 0.1, 0.3, 0.5, and 0.7 mg/kg of Se from DL-SeMet, respectively. The trial lasted for 42 days. Results： Pigs supplemented with 0.3 and 0.7 mg/kg DL-SeMet obtained better feed gain ratio （P 〈 0.05）. The best antioxidant ability （serum, liver, and muscle） was shown in 0.1-0.3 mg/kg DL-SeMet groups （P〈 0.05）. The plasma Se concentration increased as the dietary DL-SeMet level elevated. The immunity among groups was not affected. Conclusions： DL-SeMet supplementation in the diet significantly improved the growth performance, antioxidant ability and plasma Se content of weaning pigs. DL-SeMet can replace sodium selenite in the diet of weaning pigs.
基金PICAjinomoto HeartlandNovus International listed in the author section fully financially supported this study
文摘Background: The use of feed grade amino acids can reduce the cost of lactation feed. With changing genetics,increasing feed costs, and higher number of pigs weaned with heavier wean weights further evaluation of higher inclusion levels of feed-grade amino acid in lactation diets than previously published is warranted. Two experiments(Exp.) were conducted to determine the optimal inclusion level of L-lysine HCl to be included in swine lactation diets while digestible lysine levels remain constant across dietary treatments and allowing feed grade amino acids to be added to the diet to maintain dietary ratios relative to lysine to maximize litter growth rate and sow reproductive performance. Furthermore, the studies were to evaluate minimal amino acid ratios relative to lysine that allows for optimal litter growth rate and sow reproductive performance.Results: Exp. 1: Increasing L-lysine HCl resulted in similar gilt feed intake, litter, and reproductive performance.Average litter gain from birth to weaning was 2.51, 2.49, 2.59, 2.43, and 2.65 kg/d when gilts were fed 0.00, 0.075,0.150, 0.225, and 0.30% L-lysine HCl, respectively. Exp. 2: The average litter gain from birth to weaning was 2.68,2.73, 2.67, 2.70, and 2.64 kg/d(P < 0.70) when sows were fed 0.1, 0.2, 0.3, 0.4, and 0.4% L-lysine HCl plus valine,respectively. No other differences among dietary treatments were observed.Conclusions: Collectively, these studies demonstrate corn-soybean meal based lactation diets formulated with a constant SID lysine content for all parities containing up to 0.40% L-lysine HCl with only supplemental feed grade threonine and a methionine source have no detrimental effect on litter growth rate and subsequent total born.
文摘To investigate the antibacterial activity of commercial organic acid Activate WD （WD）, the minimal inhibitory concentration （MIC） and minimal bactericidal concentration （MBC） of WD against Staphylococcus aureus, Escherichia coli, Salmonella pullorum, and Campylobacter jejuni were determined by double broth dilution method. Bacteria were added in a mixture of water and commercial broiler feed adjusted by WD into pH 3.0, 4.0, and 5.0; the survival of bacteria was determined by a direct plate count method at 0, 0.5, 1, 4, 8, and 24 h after being mixed to test the bactericidal potential of WD. The results showed that the MIC of WD against four bacteria was 0.3125%, and the MBC was 0.625%. At pH 3.0, bacteria could not survive. Campylobacter jejuni died after 4 h of incubation at pH 4.0, 5.0, whereas for other three bacteria, the bacterium numbers were below detection limits until 8 h of incubation. In conclusion, WD had significant antibacterial activity, and could be used on farms to prevent cross-infection via rearing water.
文摘Proximate nutrient composition (crude protein, non-fiber carbohydrates, crude fiber, and ash), fiber fractions (neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin), and both macro (calcium (Ca), phosphorus (P), magnesium (Mg), potassium (K), sodium (Na), and sulfur (S)) and trace (copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), and zinc (Zn)) mineral profiles were quantified in mixed pasture samples collected during the wet (n = 8) and dry (n = 15) seasons in north central Uganda. Metabolizable and Net Energy values for dairy production were estimated based on standard calculations, and samples were compared seasonally. Crude fat (p = 0.05) and lignin (p = 0.01) values were lower in the dry compared with the wet season, linked with reduced plant growth. Crude protein (13.0% of dry matter (DM)), fiber fractions, and calculated energy content did not vary seasonally in this data set, and reflected chemical components of a grass-dominated system that appeared energetically limiting for production livestock. Mineral constituents varied more dramatically by season, with Ca, Mg, Cu, and Mn lower (all 0.05) and K higher in the dry season. Sodium was deficient in these pastures, whereas Ca, P, Mg, S, Cu, and Zn concentrations may have been only marginally sufficient, particularly to meet needs for lactation, dependent on season. These limited data suggest that a high-energy mineral supplement may prove beneficial in meeting nutritional and production needs of multiple grazing ruminant species in this region, particularly during dry seasons.
基金Novus International Trading(Shanghai)Co.,LtdInternational(regional)cooperation and exchange program of NSFC(3191101579).
文摘This experiment evaluated the impacts of essential oils(EO)and protease(PRO),independently or in combination,on growth performance,antioxidation,inflammation and intestinal function of weaned pigs.One hundred and sixty weaned pigs(21 d of age,BW of 6.74±0.20 kg)were randomly divided into 4 treatments with 8 replicate pens of 5 pigs per pen.Dietary treatments included the following:1)control diet(CON),2)CON with 300 mg/kg essential oils(EO),3)CON with 500 mg/kg protease(PRO),4)CON with 300 mg/kg essential oil and 500 mg/kg protease(EO + PRO).On d 8,one pig from each penwas selected for sampling.The remaining pigs were fed for an additional week and growth performance was monitored during this period.Dietary treatments had no marked effects(P>0.05)on the growth performance of pigs.However,pigs receiving EO diet had higher(P<0.05)serumglutathione peroxidase(GSH-Px)activity,and tended to decrease(P=0.063)serum concentration of tumor necrosis factor-a(TNF-a).In addition,pigs receiving EO diet had higher(P<0.05)abundances of phylum Actinobacteria,and genera Bifidobacterium,and lower(P<0.05)phylum Bacteroidetes and genera Alloprevotella in colonic digesta.Pigs receiving PRO diet decreased(P<0.05)the serum concentration of malondialdehyde(MDA)and diamine oxidase activity,increased(P<0.05)the villus height and the ratio of villus height to crypt depth in duodenum,increased sucrase activity in jejunal mucosa,and also increased the abundance of phylum Actinobacteria in colonic digesta.Furthermore,the synergistic effects of EO and PROwas observed(P<0.05)for pigs with decreasing serum TNF-a concentration and increasing serum GSH-Px activity.Collectively,the results indicated that dietary supplementation of EO and PRO had no significant effects on growth performance of weaned pigs.EO diet appeared to improve antioxidant activity and intestinal microbiota,while PRO diet improved intestinal morphology and digestive enzyme activity,and there was a synergistic effect of EO and PRO on reducing inflammatory parameters in weaned pigs.
文摘The goal of this review article,based on a systematic literature search,is to critically assess the state of knowledge and experimental methodologies used to delineate the conversion and metabolism of the 2 methionine(Met)sources DL-methionine(DL-Met)and DL-2-hydroxy-4-(methylthio)butanoic acid(HMTBa).The difference in the chemical structures of HMTBa and DL-Met indicates that these molecules are absorbed and metabolized differently in animals.This review explores the methodologies used to describe the 2-step enzymatic conversion of the 3 enantiomers(D-HMTBa,L-HMTBa and D-Met)to L-Met,as well as the site of conversion at the organ and tissue levels.Extensive work was published documenting the conversion of HMTBa and D-Met into L-Met and,consequently,the incorporation into protein using a variety of in vitro techniques,such as tissue homogenates,cell lines,primary cell lines,and everted gut sacs of individual tissues.These studies illustrated the role of the liver,kidney,and intestine in the con-version of Met precursors into L-Met.A combination of in vivo studies using stable isotopes and infusions provided evidence of the wide conversion of HMTBa to L-Met by all tissues and how some tissues are net users of HMTBa,whereas others are net secreters of L-Met derived from HMTBa.Conversion of D-Met to L-Met in organs other than the liver and kidney is poorly documented.The methodology cited in the literature to determine conversion efficiency ranged from measurements of urinary,fecal,and respiratory excretion to plasma concentration and tissue incorporation of isotopes after intraperitoneal and oral in-fusions.Differences observed between these methodologies reflect differences in the metabolism of Met sources rather than differences in conversion efficiency.The factors affecting conversion efficiency are explored in this paper and are mostly associated with extreme dietary conditions,such as noncommercial crystalline diets that are very deficient in total sulfur amino acids with respect to requirements.Impli-cations in the diversion of the 2 Met sources toward transsulfuration over transmethylation pathways are discussed.The strengths and weaknesses of some methodologies used are discussed in this review.From this review,it can be concluded that due to the inherent differences in conversion and metabolism of the 2 Met sources,the experimental methodologies(e.g.,selecting different organs at different time points or using diets severely deficient in Met and cysteine)can impact the conclusions of the study and may explain the apparent divergences of conclusion found in the literature.It is recommended when con-ducting studies or reviewing the literature to properly select the experimental models that allow for differences in how the 2 Met precursors are converted to L-Met and metabolized by the animal to enable a proper comparison of their bioefficacy.
文摘This literature review evaluates the absorption of methionine (Met) sources such as 2-hydroxy-4-methylthiobutyric acid (HMTBa), its calcium salts (HMTBa-Ca), and DL-methionine (DL-Met) by focusing on the state of knowledge regarding the absorption mechanism, experimental methodology, and factors affecting their absorption. The 2 Met sources differ in mechanism and site of absorption due to differences in their chemical characteristics and enzymatic conversion. This review addresses diffusion- and transport-mediated absorption systems for amino acids and carboxylic compounds, best elucidated by in vitro, ex vivo, and in vivo experimental models. Opportunities and limitations in the use of radioisotopes to depict absorption sites as well as host and microbial metabolism are described. Physiological and environmental conditions that lead to changes in gut absorptive capacity and the impact of Met source absorption are also evaluated. This review concludes that any comparison between HMTBa and DL-Met should consider their different behaviors during the absorption phase. Hence, the chemical characteristics of these 2 molecules entail different absorption sites and mechanisms, from passive absorption in the case of HMTBa and HMTBa-Ca to active transporters for DL-Met, HMTBa, and HMTBa-Ca. In addition, the different conversion modes of these 2 molecules further differentiate their absorption modes. Considering these important differences, it is easier to understand the apparent divergence between the conclusions of existing publications. When comparing these 2 molecules, it is recommended to properly adapt to the conditions under which the absorption of Met sources is evaluated.
基金supported by Fondo di Ateneo per la Ricerca 2019 FAR2019MARONGIU-Studio di sistemi alternativi di gestione della fase riproduttiva rispettosi della fisiologia e del benessere della coniglia-of University of Sassari。
文摘Our publication on absorption of methionine sources(Becquet et al.,2023a)is a thorough analysis of 129 references dealing with absorption of sources of methionine,with the objective to critically evaluate the methodologies used and their impact on the conclusions of the studies.As the focus of our publicationwas on the evaluation of absorption,efficacy studies and reports not having information on absorption were not considered(Elwert et al.,2008;Rychen et al.,2008).
