This study aimed to investigate the limitations and interactive effects of dietary crude protein(CP;15%,17%and 19%),excess branched-chain amino acid(BCAA)inclusions(0%,20%and 40%),and net energy(NE;9.0,9.7 and 10.4 MJ...This study aimed to investigate the limitations and interactive effects of dietary crude protein(CP;15%,17%and 19%),excess branched-chain amino acid(BCAA)inclusions(0%,20%and 40%),and net energy(NE;9.0,9.7 and 10.4 MJ/kg)on performance and nutrient utilization for Cobb 500 mix-sex broilers,using a Box-Behnken design.The study consisted of 2 experiments:Exp.1 involved 1092 chickens,and their performance was measured from d 19 to 35,and Exp.2 employed 156 birds for NE measurements from d 25 to 28.Both experiments used the same diets(n=13),each replicated 7 times for Exp.1 and 6 times for Exp.2.On d 35,4 birds per pen(2 males and 2 females)were sampled to collect ileal digesta and weigh carcass parts.Feed intake(FI),NE intake(NEi),weight gain(WG),feed conversion ratio(FCR)and breast yield were affected by CP×NE(P<0.001)and CP×BCAA(P=0.041).Diluting NE in the reduced CP(RP)-diets led to a higher FI(P<0.001)and breast yield(P<0.001)than high NE,but the NE levels had no effect(P>0.05)on FI and breast yield in high CP(HCP)-diets.Breast yield increased(P=0.041)with BCAA in HCP-diets,whereas in the RP-diets,the yield lowered(P=0.041)with increased BCAA.A similar trend was observed with fat content:in HCP-diets,fat content increased(P=0.007)with BCAA,while in RP-diets,fat content decreased(P=0.007)with higher BCAA levels.In addition,increasing BCAA in the RP-diets decreased(P<0.001)FI,NEi,WG and increased FCR(P=0.001)than low BCAA.However,BCAA levels had no effect(P>0.05)on these measurements in HCP-diets.High NE increased(P<0.001)NEi and decreased(P<0.001)FCR compared to low NE in the HCP-diets.However,the NE effect on both measurements did not differ(P>0.05)in RP-diets.These results indicate that increasing BCAA levels beyond the recommended amounts in RP-diets impairs energy utilization,leading to poor performance.展开更多
Different energy systems have been proposed for energy evaluation of feeds for domestic animals.The oldest and most commonly used systems take into account the fecal energy loss to obtain digestible energy(DE),and fec...Different energy systems have been proposed for energy evaluation of feeds for domestic animals.The oldest and most commonly used systems take into account the fecal energy loss to obtain digestible energy(DE),and fecal,urinary and fermentation gases energy losses to calculate metabolizable energy(ME).In the case of ruminants and pigs,the net energy(NE)system,which takes into account the heat increment associated with the metabolic utilization of ME,has progressively replaced the DE and ME systems over the last 50 years.For poultry,apparent ME(AME)is used exclusively and NE is not yet used widely.The present paper considers some important methodological points for measuring NE in poultry feeds and summarizes the available knowledge on NE systems for poultry.NE prediction equations based on a common analysis of three recent studies representing a total of 50 complete and balanced diets fed to broilers are proposed;these equations including the AME content and easily available chemical indicators have been validated on another set of 30 diets.The equations are applicable to both ingredients and complete diets.They rely primarily on an accurate and reliable AME value which then represents the first limiting predictor of NE value.Our analysis indicates that NE would be a better predictor of broiler performance than AME and that the hierarchy between feeds is dependent on the energy system with a higher energy value for fat and a lower energy value for protein in an NE system.Practical considerations for implementing such an NE system from the commonly used AME or AMEn(AME adjusted for zero nitrogen balance)systems are presented.In conclusion,there is sufficient information to allow the implementation of the NE concept in order to improve the accuracy of feed formulation in poultry.展开更多
This study evaluated the effect of multi-carbohydrase(MC)on energy and nitrogen(N)balance and gene expression in broilers fed diets with different crude protein(CP)contents.The study employed a 2×2 factorial arra...This study evaluated the effect of multi-carbohydrase(MC)on energy and nitrogen(N)balance and gene expression in broilers fed diets with different crude protein(CP)contents.The study employed a 2×2 factorial arrangement of treatments.The factors were presence or absence of MC,and standard(SCP)or low(LCP)dietary CP concentration.A 3-phase feeding program was used,including starter(0 to 7 d),grower(8 to 17 d)and finisher(18 to 28 d)phases.The study was undertaken in closed calorimetry chambers.Each of the 4 dietary treatments was replicated 8 times in total across 2 runs,with 2 birds per replicate(n=64).Data for energy partitioning and N balance were collected from d 25 to 28.On d 28,birds were euthanized to collect muscle and intestinal tissue samples for gene expression.The results showed that the MC increased apparent metabolizable energy(AME,P<0.01)and net energy(NE,P<0.05),and reduced the feed conversion ratio(FCR,P<0.01)in all diets.The proportion of energy retained as fat per total energy retention(REf/RE)was positively correlated with feed AME and NE(r=0.541,P<0.01 and r=0.665,P<0.001,respectively),suggesting that feed energy augmented with increased fat gain.Muscle ATP synthase subunit alpha(ATPSA1W)gene expression had a positive cor-relation with REf/RE and feed NE(r=0.587,P<0.001 and r=0.430,P<0.05,respectively).Similarly,muscle peroxisome proliferator-activated receptor gamma coactivator 1 alpha(PGC-1A)expression was negatively correlated with weight gain and positively correlated with FCR(r-0.451,P<0.05 and r-0.359,P<0.05,respectively).These correlations show that over-expressions of muscle genes related to energy production reduce bird performance.This study demonstrated that MC increase dietary energy utilization,regardless of dietary CP concentration.However,the energy released by the enzymes in-creases feed energy-to-CP ratio,meaning there is excess energy that is then deposited as body fat.This suggests that supplemental MC in broiler feeds is beneficial if diets are formulated to contain marginal energy levels.展开更多
Diet is a major modulator of animal resilience and its three pillars:host's immune response,gut microbiota,and intestinal barrier.In the present study,we endeavour to delineate a challenging con-dition aimed to de...Diet is a major modulator of animal resilience and its three pillars:host's immune response,gut microbiota,and intestinal barrier.In the present study,we endeavour to delineate a challenging con-dition aimed to degrade these pillars and elucidate its impact on broiler performance and nutrient di-gestibility.To attain this objective,we opted to use guar gum(GG)as a source of galactomannan.A series of three in vivo experiments were conducted employing conventional or semi-purified diets,supple-mented with or without GG during the grower phase(14-28 d).Our findings demonstrate a substantial decline in animal performance metrics such as body weight(reduced by 29%,P<0.001),feed intake(decreased by 12%,P<0.001),and feed conversion ratio(up to 58%increase,P<0.001)in the presence of GG at 2%.The supplementation of a semi-purified diet with incremental doses of GG resulted in a linear reduction(P<0.001)in the apparent total tract digestibility of dry matter and apparent metabolisable energy.Additionally,a marked reduction in ileal endogenous losses,as well as apparent and standardised digestibility of all amino acids with varying proportions(P<0.05),was observed.These alterations were accompanied by disrupted gut integrity assessed by fluorescein isothiocyanate-dextran(FITC-d)(P<0.001)as well as an inflammatory status characterised by elevated levels of acute-phase proteins,namely orosomucoid and serum amyloid A in the sera(P=0.03),and increased mRNA expression levels of IL-1,IL-6,IL-8,Inos,and K203 genes in the ileum,along with a decrease in IgA levels in the gut lumen(P<0.05).Microbial ecology and activity were characterised by reduced diversity and richness(Shannon index,P=0.005)in the presence of GG.Consequently,our results revealed diminished levels of short-chain fatty acids(P=0.01)and their producer genera,such as Clostridium_XIVa and Blautia,in the gut caeca,coupled with excessive accumulation of lactate(17-fold increase,P<0.01)in the presence of GG at 2%.In addition to providing a more comprehensive characterisation of the GG supplementation as a leaky gut model,our results substantiate a thorough understanding of the intricate adjustments and interplay between the intestinal barrier,immune response,and microbiota.Furthermore,they underscore the significance of feed components in modulating these dynamics.展开更多
基金funded by Adisseo France in partnership with AgriFutures Australia and Poultry Hub Australia.
文摘This study aimed to investigate the limitations and interactive effects of dietary crude protein(CP;15%,17%and 19%),excess branched-chain amino acid(BCAA)inclusions(0%,20%and 40%),and net energy(NE;9.0,9.7 and 10.4 MJ/kg)on performance and nutrient utilization for Cobb 500 mix-sex broilers,using a Box-Behnken design.The study consisted of 2 experiments:Exp.1 involved 1092 chickens,and their performance was measured from d 19 to 35,and Exp.2 employed 156 birds for NE measurements from d 25 to 28.Both experiments used the same diets(n=13),each replicated 7 times for Exp.1 and 6 times for Exp.2.On d 35,4 birds per pen(2 males and 2 females)were sampled to collect ileal digesta and weigh carcass parts.Feed intake(FI),NE intake(NEi),weight gain(WG),feed conversion ratio(FCR)and breast yield were affected by CP×NE(P<0.001)and CP×BCAA(P=0.041).Diluting NE in the reduced CP(RP)-diets led to a higher FI(P<0.001)and breast yield(P<0.001)than high NE,but the NE levels had no effect(P>0.05)on FI and breast yield in high CP(HCP)-diets.Breast yield increased(P=0.041)with BCAA in HCP-diets,whereas in the RP-diets,the yield lowered(P=0.041)with increased BCAA.A similar trend was observed with fat content:in HCP-diets,fat content increased(P=0.007)with BCAA,while in RP-diets,fat content decreased(P=0.007)with higher BCAA levels.In addition,increasing BCAA in the RP-diets decreased(P<0.001)FI,NEi,WG and increased FCR(P=0.001)than low BCAA.However,BCAA levels had no effect(P>0.05)on these measurements in HCP-diets.High NE increased(P<0.001)NEi and decreased(P<0.001)FCR compared to low NE in the HCP-diets.However,the NE effect on both measurements did not differ(P>0.05)in RP-diets.These results indicate that increasing BCAA levels beyond the recommended amounts in RP-diets impairs energy utilization,leading to poor performance.
文摘Different energy systems have been proposed for energy evaluation of feeds for domestic animals.The oldest and most commonly used systems take into account the fecal energy loss to obtain digestible energy(DE),and fecal,urinary and fermentation gases energy losses to calculate metabolizable energy(ME).In the case of ruminants and pigs,the net energy(NE)system,which takes into account the heat increment associated with the metabolic utilization of ME,has progressively replaced the DE and ME systems over the last 50 years.For poultry,apparent ME(AME)is used exclusively and NE is not yet used widely.The present paper considers some important methodological points for measuring NE in poultry feeds and summarizes the available knowledge on NE systems for poultry.NE prediction equations based on a common analysis of three recent studies representing a total of 50 complete and balanced diets fed to broilers are proposed;these equations including the AME content and easily available chemical indicators have been validated on another set of 30 diets.The equations are applicable to both ingredients and complete diets.They rely primarily on an accurate and reliable AME value which then represents the first limiting predictor of NE value.Our analysis indicates that NE would be a better predictor of broiler performance than AME and that the hierarchy between feeds is dependent on the energy system with a higher energy value for fat and a lower energy value for protein in an NE system.Practical considerations for implementing such an NE system from the commonly used AME or AMEn(AME adjusted for zero nitrogen balance)systems are presented.In conclusion,there is sufficient information to allow the implementation of the NE concept in order to improve the accuracy of feed formulation in poultry.
基金The authors gratefully acknowledge Adisseo France for financial support of this study.
文摘This study evaluated the effect of multi-carbohydrase(MC)on energy and nitrogen(N)balance and gene expression in broilers fed diets with different crude protein(CP)contents.The study employed a 2×2 factorial arrangement of treatments.The factors were presence or absence of MC,and standard(SCP)or low(LCP)dietary CP concentration.A 3-phase feeding program was used,including starter(0 to 7 d),grower(8 to 17 d)and finisher(18 to 28 d)phases.The study was undertaken in closed calorimetry chambers.Each of the 4 dietary treatments was replicated 8 times in total across 2 runs,with 2 birds per replicate(n=64).Data for energy partitioning and N balance were collected from d 25 to 28.On d 28,birds were euthanized to collect muscle and intestinal tissue samples for gene expression.The results showed that the MC increased apparent metabolizable energy(AME,P<0.01)and net energy(NE,P<0.05),and reduced the feed conversion ratio(FCR,P<0.01)in all diets.The proportion of energy retained as fat per total energy retention(REf/RE)was positively correlated with feed AME and NE(r=0.541,P<0.01 and r=0.665,P<0.001,respectively),suggesting that feed energy augmented with increased fat gain.Muscle ATP synthase subunit alpha(ATPSA1W)gene expression had a positive cor-relation with REf/RE and feed NE(r=0.587,P<0.001 and r=0.430,P<0.05,respectively).Similarly,muscle peroxisome proliferator-activated receptor gamma coactivator 1 alpha(PGC-1A)expression was negatively correlated with weight gain and positively correlated with FCR(r-0.451,P<0.05 and r-0.359,P<0.05,respectively).These correlations show that over-expressions of muscle genes related to energy production reduce bird performance.This study demonstrated that MC increase dietary energy utilization,regardless of dietary CP concentration.However,the energy released by the enzymes in-creases feed energy-to-CP ratio,meaning there is excess energy that is then deposited as body fat.This suggests that supplemental MC in broiler feeds is beneficial if diets are formulated to contain marginal energy levels.
文摘Diet is a major modulator of animal resilience and its three pillars:host's immune response,gut microbiota,and intestinal barrier.In the present study,we endeavour to delineate a challenging con-dition aimed to degrade these pillars and elucidate its impact on broiler performance and nutrient di-gestibility.To attain this objective,we opted to use guar gum(GG)as a source of galactomannan.A series of three in vivo experiments were conducted employing conventional or semi-purified diets,supple-mented with or without GG during the grower phase(14-28 d).Our findings demonstrate a substantial decline in animal performance metrics such as body weight(reduced by 29%,P<0.001),feed intake(decreased by 12%,P<0.001),and feed conversion ratio(up to 58%increase,P<0.001)in the presence of GG at 2%.The supplementation of a semi-purified diet with incremental doses of GG resulted in a linear reduction(P<0.001)in the apparent total tract digestibility of dry matter and apparent metabolisable energy.Additionally,a marked reduction in ileal endogenous losses,as well as apparent and standardised digestibility of all amino acids with varying proportions(P<0.05),was observed.These alterations were accompanied by disrupted gut integrity assessed by fluorescein isothiocyanate-dextran(FITC-d)(P<0.001)as well as an inflammatory status characterised by elevated levels of acute-phase proteins,namely orosomucoid and serum amyloid A in the sera(P=0.03),and increased mRNA expression levels of IL-1,IL-6,IL-8,Inos,and K203 genes in the ileum,along with a decrease in IgA levels in the gut lumen(P<0.05).Microbial ecology and activity were characterised by reduced diversity and richness(Shannon index,P=0.005)in the presence of GG.Consequently,our results revealed diminished levels of short-chain fatty acids(P=0.01)and their producer genera,such as Clostridium_XIVa and Blautia,in the gut caeca,coupled with excessive accumulation of lactate(17-fold increase,P<0.01)in the presence of GG at 2%.In addition to providing a more comprehensive characterisation of the GG supplementation as a leaky gut model,our results substantiate a thorough understanding of the intricate adjustments and interplay between the intestinal barrier,immune response,and microbiota.Furthermore,they underscore the significance of feed components in modulating these dynamics.
