Study on Residues and Digestion of Cyantraniliprole in Chewing Cane

[Objective]The paper was to establish a method for the determination of cyantraniliprole residue in chewing cane,and analyze the residue and digestion dynamics of cyantraniliprole in chewing cane.[Method]The chewing cane samples were extracted by acetonitrile,purified by improved QuEChERS method,and detected by UPLC/MS/MS.[Result]Cyananseramide showed a good linear relationship in the concentration range of 0.005-0.250 mg/L(R2=0.9991).When the added mass concentration ranged from 0.02 to 0.40 mg/kg,the recovery rates of cyantraniliprole were respectively 83.1%-110.1%for chewing cane leaves and 88.2%-109.2%for chewing cane stems;the relative standard deviations were respectively2.38%-7.98%for chewing cane leaves and 2.26%-3.10%for chewing cane stems.The limit of detection(LOD)in chewing cane was 0.05μg/kg and the limit of quantification(LOQ)was 0.02 mg/kg.The trial results of two chewing cane fields in Guangxi showed that the half-lives of cyantraniliprole in chewing cane leaves were 7.76 and 6.12 d,respectively,and the correlation coefficients were 0.9570 and 0.9241,respectively.[Conclusion]The method is sensitive,accurate,simple and rapid,and it can be used to determine the residue and half-life of cyantraniliprole in chewing cane.The results will provide technical support for the safe use of cyantraniliprole in chewing cane.

Protein digestive dynamics of meat and bone meals in broiler chickens

This study determined the variations in protein digestibilities and digestion rates in broiler chickens offered diets containing 7 different meat and bone meals(MBM).A total of 252 male Ross 308 broiler chickens were offered 7 atypical diets largely based on maize and MBM from 24 to 28 d post-hatch.Each experimental diet was offered to 6 replicates with 6 birds per replicate cage.Excreta were collected in their entirety from 25 to 27 d post-hatch and on 28 d post-hatch.Digesta samples were collected from the proximal jejunum,distal jejunum,proximal ileum and distal ileum.Apparent digestibilities of protein were determined in each segment and apparent digestibilities of amino acids were measured in the distal ileum.There were significant differences in apparent protein digestibility coefficients in the proximal jejunum(P=0.006),where broiler chickens offered the high ash beef meal(diet 7)generated the lowest protein digestibility in the proximal jejunum(0.318).Similarly,there were significant differences in apparent digestibility coefficients in the distal jejunum(P<0.001)and distal ileum(P<0.001)but not in the proximal ileum.More pronounced differences were found in the disappearance rate of protein and there were significant differences in all 4 segments of the small intestine(P<0.001).Broiler chickens offered the high ash beef meal had the lowest protein disappearance rate(P<0.001).No difference was observed in the predicted protein digestion rate(P=0.486)but chickens offered the high ash beef meal had the lowest potential digestible protein(0.662,P=0.034)whereas the highest potential digestible protein(0.739)was detected in diet 5(containing a beef meal).This study contributed to the establishment of a preliminary database to include digestion rates of starch and protein into practical diet formulation.

Protein sources and starch-protein digestive dynamics manipulate growth performance in broiler chickens defined by an equilateraltriangle response surface design

A total of 360 male,off-sex Ross 308 chicks were offered 10 dietary treatments from 14 to 35 d post ehatch in an equilateral-triangle response surface design feeding study in order to confirm the importance of protein and amino acid digestive dynamics in broiler chickens.The 3 apical diets were nutritionally-equivalent containing either soybean meal,non-bound amino acids or whey protein concentrate as the major source of dietary protein and amino acids.Appropriate blends of the 3 apical diets comprised the balance of 7 diets and each dietary treatment was offered to 6 replicate cages with 6 birds per cage.Growth performance,nutrient utilisation,apparent protein and starch digestibility coefficients were determined in 4 small intestinal segments.The optimal weight gain(2,085 g/bird)and feed conversion ratios(FCR,1.397)were generated by Diet 50S50W which included a 50:50 blend of apical diets rich in whey protein concentrate and soybean meal.Broiler chickens offered Diet 50S50W also had the highest experimental and predicted jejunal digestibility(0.685 in proximal jejunum and 0.823 in distal jejunum).FCR was not correlated with apparent distal ileal digestibility coefficient(P>0.05)of protein but was correlated with apparent protein digestibility in proximal jejunum(r=-0.369,P=0.040)and distal jejunum(r=-0.316,P=0.015).Surplus dietary starch was correlated with increased fat pad weight(r=0.781,P?0.008).The findings confirmed the relevance of protein digestion rate,reflected by jejunal digestibility,on feed conversion of broiler chickens.A balance between protein-bound and non-bound crystalline or synthetic amino acids may be required for optimal growth and protein digestion.

Starch digestion rates in multiple samples of commonly used feed grains in diets for broiler chickens

In this study the starch digestion rates in broiler chickens from 18 samples of 5 commonly used feed grains(sorghum,wheat,maize,barley,triticale)were determined.The methodology to determine starch digestion rates in poultry is detailed herein.Starch digestion rates were not significantly different(P-0.128)across the 18 feed grains,which reflects the wide variations that were observed within a given feedstuff.Nevertheless,starch digestion rates in broiler chickens offered wheat-based diets were significantly more rapid by 56.0%(0.117 versus 0.075 min-1;p=0.012)than their sorghum-based counterparts on the basis of a pair-wise comparison.In descending order,the following starch diges-tion rates were observed:wheat(0.117 min-1),barley(0.104 min-1),triticale(0.093 min-1),maize(0.086 min-1),sorghum(0.075 min-1).The implications of these findings are discussed as they almost certainly have implications for poultry nutrition and the development of reduced crude protein diets for broiler chickens.

Facilitating the acceptance of tangibly reduced-crude protein diets for chicken-meat production

Inclusions of non-bound amino acids particularly methionine,lysine and threonine,together with the"ideal protein"concept have allowed nutritionists to formulate broiler diets with reduced crude protein(CP)and increased nutrient density of notionally"essential"amino acids and energy content in recent decades,However,chicken-meat production has been projected to double between now and 2050,providing incentives to reduce dietary soybean meal inclusions further by tangibly reducing dietary CP and utilising a larger array of non-bound amino acids.Whilst relatively conservative decreases in dietary CP,in the order of 20 to 30 g/kg,do not negatively impact broiler performance,further decreases in CP typically compromise broiler performance with associated increases in carcass lipid deposition.Increases in carcass lipid deposition suggest changes occur in dietary energy balance,the mechanisms of which are still not fully understood but discourage the acceptance of diets with reductions in CP,Nevertheless,the groundwork has been laid to investigate both amino acid and non-amino acid limitations and propose facilitative strategies for adoption of tangible dietary CP reductions;consequently,these aspects are considered in detail in this review.Unsurprisingly,investigations into reduced dietary CP are epitomised by variability broiler performance due to the wide range of dietary specifications used and the many variables that should,or could,be considered in formulation of experimental diets.Thus,a holistic approach encompassing many factors influencing limitations to the adoption of tangibly reduced CP diets must be considered if they are to be successful in maintaining broiler performance without increasing carcass lipid deposition.