Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows

Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracted SBMs from soybeans produced in the USA,Brazil,and China were selected.In Exp.1,eight different diets were created:a nitrogen(N)-free diet and 7 experimental diets containing SBM from different origins as the only N source.Eight non-pregnant,multiparous sows were arranged in an 8×8 Latin square design(8 periods and 8 diets).In Exp.2,the diet formula was the same as in Exp.1.Eight gestating sows(parity 3)were assigned to 4 different diets in a replicated 4×3 Youden square design(three periods and four diets)in mid-gestation and again in late-gestation stages.Results When fed to non-pregnant and late-gestating sows,the standardized ileal digestibility(SID)of CP and most AAs from different SBM were not significantly different(P>0.05).When fed to mid-gestating sows,the SID values for Arg,His,Lys,Phe,Cys,Gly,Ser,and Tyr in SBM 1 were lower than in SBM 4 and 5(P<0.05),whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4(P<0.05).SID values for Ile,Ala,and Asp from SBM 4 were lower than in SBM 1 and 5(P<0.05).Sows had significantly greater SID values for Lys,Ala,and Asp during mid-gestation when compared with late-gestation stages(P<0.05).Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows(P<0.01),whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows(P<0.01).Conclusions When fed to mid-gestating sows,the SID values for most AAs varied among SBM samples.The SID values for Lys,Met,Val,Ala,Asp,and Tyr in SBM were affected by sow gestation stages.Our findings provide a cornerstone for accurate SBM use in sow diets.

Implications of vitamin D for flesh quality of grass carp(Ctenopharyngodon idella):antioxidant ability,nutritional value,sensory quality,and myofiber characteristics

Background Muscle represents a unique and complex system with many components and comprises the major edible part of animals.Vitamin D is a critical nutrient for animals and is known to enhance calcium absorption and immune response.In recent years,dietary vitamin D supplementation in livestock has received increased attention due to biological responses including improving shear force in mammalian meat.However,the vitamin D acquisition and myofiber development processes in fish differ from those in mammals,and the effect of vitamin D on fish flesh quality is poorly understood.Here,the influence of dietary vitamin D on fillet quality,antioxidant ability,and myofiber development was examined in grass carp(Ctenopharyngodon idella).Methods A total of 540 healthy grass carp,with an initial average body weight of 257.24±0.63 g,were allotted in 6 experimental groups with 3 replicates each,and respectively fed corresponding diets with 15.2,364.3,782.5,1,167.9,1,573.8,and 1,980.1 IU/kg vitamin D for 70 d.Results Supplementation with 1,167.9 IU/kg vitamin D significantly improved nutritional value and sensory quality of fillets,enhancing crude protein,free amino acid,lipid,and collagen contents;maintaining an ideal pH;and reduc-ing lactate content,shear force,and cooking loss relative to respective values in the control(15.2 IU/kg)group.Average myofiber diameter and the frequency of myofibers>50μm in diameter increased under supplementation with 782.5–1,167.9 IU/kg vitamin D.Levels of oxidative damage biomarkers decreased,and the expression of antioxi-dant enzymes and nuclear factor erythroid 2-related factor 2 signaling molecules was upregulated in the 1,167.9 IU/kg vitamin D treatment compared to respective values in the control group.Furthermore,vitamin D supplementation activated cell differentiation by enhancing the expression of myogenic regulatory factors and myocyte enhancer factors compared to that in the control group.In addition,supplementation with 1,167.9 IU/kg vitamin D improved protein deposition associated with protein synthesis molecule(target of rapamycin)signaling and vitamin D receptor paralogs,along with inhibition of protein degradation(forkhead box protein 1)signaling.Conclusions Overall,the results demonstrated that vitamin D strengthened antioxidant ability and myofiber devel-opment,thereby enhancing nutritional value and sensory quality of fish flesh.These findings suggest that dietary vitamin D supplementation is conducive to the production of nutrient-rich,high quality aquaculture products.

Comparative effects of enzymatic soybean,fish meal and milk powder in diets on growth performance,immunological parameters,SCFAs production and gut microbiome of weaned piglets

Background:The objective of this study was to evaluate the replacement effects of milk powder(MK)and fish meal(FM)by enzymatic soybean(ESB)in diets on growth performance,immunological parameters,SCFAs production and gut microbiome of weaned piglets.Methods:A total of 128 piglets with initial body weight at 6.95±0.46 kg,were randomly assigned into 4 dietary treatments with 8 replicates per treatment and 4 piglets per replicate for a period of 14 d.Piglets were offered isonitrogenous and iso-energetic diets as follows:CON diet with MK and FM as high quality protein sources,ESB plus FM diet with ESB replacing MK,ESB plus MK diet with ESB replacing FM,and ESB diet with ESB replacing both MK and FM.Results:No significant differences were observed in growth performance among all treatments(P>0.05).However,piglets fed ESB plus FM or ESB diet had increased diarrhea index(P<0.01),and lower digestibility of dry matter(DM),gross energy(GE)or crude protein(CP),relative to piglets fed CON diet(P<0.01).Moreover,the inclusion of ESB in diet markedly decreased the plasma concentration of HPT and fecal concentration of butyric acid(BA)(P<0.01).The High-throughput sequencing of 16S rRNA gene V3−V4 region of gut microbiome revealed that the inclusion of ESB in diet increased the alpha diversity,and the linear discriminant analysis effect size(LEfSe)showed that piglets fed with ESB plus FM or ESB diet contained more gut pathogenic bacteria,such as g_Peptococcus,g_Veillonella and g_Helicobacter.Conclusion:The inclusion of ESB in diet did not markedly affect growth performance of piglets,but the replacement of MK or both MK and FM by ESB increased diarrhea index,which could be associated with lower nutrients digestibility and more gut pathogenic bacteria.However,piglets fed diet using ESB to replace FM did not markedly affect gut health-related parameters,indicating the potential for replacing FM with ESB in weaning diet.

An elastic-plastic contact model for line contact structures

Although numerical simulation tools are now very powerful,the development of analytical models is very important for the prediction of the mechanical behaviour of line contact structures for deeply understanding contact problems and engineering applications.For the line contact structures widely used in the engineering field,few analytical models are available for predicting the mechanical behaviour when the structures deform plastically,as the classic Hertz’s theory would be invalid.Thus,the present study proposed an elastic-plastic model for line contact structures based on the understanding of the yield mechanism.A mathematical expression describing the global relationship between load history and contact width evolution of line contact structures was obtained.The proposed model was verified through an actual line contact test and a corresponding numerical simulation.The results confirmed that this model can be used to accurately predict the elastic-plastic mechanical behaviour of a line contact structure.

Simultaneous Prediction of Wheat Yield and Grain Protein Content Using Multitask Deep Learning from Time-Series Proximal Sensing

Wheat yield and grain protein content(GPC)are two main optimization targets for breeding and cultivation.Remote sensing provides nondestructive and early predictions of yield and GPC,respectively.However,whether it is possible to simultaneously predict yield and GPC in one model and the accuracy and influencing factors are still unclear.In this study,we made a systematic comparison of different deep learning models in terms of data fusion,time-series feature extraction,and multitask learning.The results showed that time-series data fusion significantly improved yield and GPC prediction accuracy with R 2 values of 0.817 and 0.809.

Differential responses of weaned piglets to supplemental porcine or chicken plasma in diets without inclusion of antibiotics and zinc oxide

This study was conducted to investigate the effects of spray-dried porcine plasma protein(SDPP)or spray-dried chicken plasma protein(SDCP)supplementation in diets without the inclusion of antibiotics and zinc oxide(ZnO)on growth performance,fecal score,and fecal microbiota in early-weaned piglets.A total of 192 healthy weaning piglets(Duroc×Landrace×Yorkshire,21 d old)were blocked by BW(6.53±0.60 kg)and randomly assigned to 4 dietary treatments:negative control(NC,basal diet),positive control(PC),basal diet+ZnO at 2 g/kg and antibiotics at 0.8 g/kg,SDPP(containing 5%SDPP),and SDCP(containing 5%SDCP).The experiment lasted 14 d.The SDPP group had higher(P<0.05)final BW,average daily gain and average daily feed intake than the NC and SDCP groups.The percentage of piglets with fecal scores at 2 or≥2 was higher(P<0.05)in the NC and SDCP groups than in the PC group.A decreased(P<0.05)bacterial alpha diversity and Bacteroidetes abundance,but increased(P<0.05)Firmicutes abundance were observed in the PC and SDPP groups when compared to the NC group.The relative abundance of Lactobacillus was higher(P<0.05)in the SDPP than in the SDCP group,and that of Streptococcus was higher(P<0.01)in the PC and SDPP groups than in the NC group.The PC group also had higher(P<0.01)Faecalibacterium abundance than the NC and SDCP groups.Additionally,the SDCP group had higher(P<0.05)serum urea nitrogen than those fed other diets,and lower(P<0.10)shortchain fatty acids to branched-chain fatty acids ratio than the PC and SDPP groups.Overall,SDPP was a promising animal protein for piglets in increasing feed intake,modifying gut microbiota profile,reducing gut protein fermentation and alleviating diarrhea frequency,thus promoting growth performance,under the conditions with limited in-feed utilization of antibiotics and ZnO.