Different dietary starch patterns in lowprotein diets:effect on nitrogen efficiency,nutrient metabolism,and intestinal flora in growing pigs

Background:Protein releases amino acids faster than starch releases glucose in digestive tract of pigs fed lowprotein(LP)diets.Poor synchronization of dietary glucose and amino acids supply leads to compromised nitrogen efficiency.Dietary starch patterns modulation may improve this situation.Methods:Growing barrows(29.7±2.0 kg)were randomly allotted into 5 dietary treatments with LP diets consisting of different purified starches.Treatments included:waxy corn starch(W LP),corn starch+waxy corn starch(C+W LP),corn starch(C LP),pea starch+waxy corn starch(P+W LP)and pea starch(P LP).In the experiment,growth performance,protein deposition,nutrient metabolism,and fecal microbial community of pigs were investigated.In vitro starch digestion was used for predicting the in vivo glucose response.Results:Dietary starch in vitro glucose release profile was determined by starch source and the ratio of amylopectin and amylose.C+W LP treatment showed decreased total nitrogen excretion and plasma citrulline concentration and improved plasma leptin concentration among treatments(P<0.05).Besides,the highest nitrogen apparent biological value,whole-body protein deposition and growth performance and lowest urinary nitrogen excretion were also observed in C+W LP treatment.Compared with the other groups,C+W LP and C LP showed increased plasma pyruvate,IGF-1,and lipase concentrations(P<0.05).The W LP group presented dramatically increased plasma alanine and urea nitrogen concentration and decreased aldolase and leptin concentrations(P<0.05).Dietary starch patterns did not make an impact on bacterial richness and diversity,but changed the taxonomic and functional structures of the microbial communities.Microbial protein fermentation product(isobutyrate and isovalerate)presented increased in P LP treatments compared with the other treatments(P<0.05).Conclusions:Dietary starch patterns modulation can regulate dietary glucose release profile,nutrient metabolism,protein turnover,and fecal microbial fermentation in pigs.The optimal dietary glucose release profile effectively strengthened whole-body protein deposition and improve nitrogen efficiency and growth performance in growing pigs fed LP diets.

Effects of Chinese Herbal Medicine Feed Additives on Growth Performance and Dietary Nutrient Metabolism of Black-bone Chickens

[Objectives]To study the effects of Chinese herbal medicine feed additives on the growth performance and dietary nutrient metabolic rate of black-one chickens.[Methods]480 pieces of 1-day-old Donglan Black-bone Chickens were selected and divided into 4 groups,with 6 replicates in each group,with 20 pieces in each replicate.Among them,group A was the control group and was fed the basal diet;the groups B,C,and D were the experimental groups,which were separately supplemented with 0.25%,0.50%and 1.00%of Chinese herbal medicine additives in the basal diet,and the experimental period was 70 d.At the end of the feeding experiment,24 experimental chickens with similar body weight were selected from each group,and the same design of the feeding experiment was used to continue to feed the original diet for the metabolic experiment to determine the nutrient metabolic rate.[Results]Except the 50-70 d stage,the average daily gain(ADG)of group B in other stages was increased by 5.00%-9.15%(P<0.05),and the average body weight of group B at 70 d was also increased by 4.86%(P<0.05);the ADG of group C at 36-49,1-49 and 1-70 d and the average individual weight at 70 d were also higher than that of group A by 5.90%,2.66%,2.68%and 2.57%,respectively(P>0.05);at 36-49 d,the average daily feed intake(ADFI)of group A was higher than that of group B by 6.04%(P<0.01),and was also higher than that of groups C and D by 5.12%and 4.13%(P<0.05),respectively;at 1-49 d,the ADFI of group A was higher than that of group C by 2.86%(P<0.05),and there was no significant difference between the four groups of experimental chickens at each stage(P>0.05);at 22-35 and 1-70 d,the feed to gain ratio(F/G)of group B was 6.32%and 3.41%lower than that of group A(P<0.05),and at 36-49 and 1-49 d,the F/G of group B was even lower;at 36-49 d,the F/G of group C was 10.15%lower than that of group A(P<0.05),and at 1-49 d,it was also lower than that of group A by 5.29%(P<0.01);there was no significant difference between the two groups at other stages.In terms of nutrient metabolism:the three different amounts of this additive have increased the metabolic rate of DM,CP,CF,NFE,CA,Ca,P,TE and other nutrients in the diet to varying degrees,especially the addition of 0.25%and 0.50%had the significant increase.[Conclusions]The addition of 0.25%Chinese herbal medicine additives in the diet can significantly improve the growth performance and main nutrient metabolic rate of Donglan Black-bone Chickens.

Swine gut microbiota and its interaction with host nutrient metabolism

Gut microbiota is generally recognized to play a crucial role in maintaining host health and metabolism.The correlation among gut microbiota,glycolipid metabolism,and metabolic diseases has been well reviewed in humans.However,the interplay between gut microbiota and host metabolism in swine remains incompletely understood.Given the limitation in conducting human experiments and the high similarity between swine and humans in terms of anatomy,physiology,polyphagy,habits,and metabolism and in terms of the composition of gut microbiota,there is a pressing need to summarize the knowledge gained regarding swine gut microbiota,its interplay with host metabolism,and the underlying mechanisms.This review aimed to outline the bidirectional regulation between gut microbiota and nutrient metabolism in swine and to emphasize the action mechanisms underlying the complex microbiomeehost crosstalk via the gut microbiotaegutebrain axis.Moreover,it highlights the new advances in knowledge of the diurnal rhythmicity of gut microbiota.A better understanding of these aspects can not only shed light on healthy and efficient pork production but also promote our knowledge on the associations between gut microbiota and the microbiomeehost crosstalk mechanism.More importantly,knowledge on microbiota,host health and metabolism facilitates the development of a precise intervention therapy targeting the gut microbiota.

Ruminal microbiota-host interaction and its effect on nutrient metabolism

Rumen microbiota has a close and intensive interaction with the ruminants.Microbiota residing in the rumen digests and ferments plant organic matters into nutrients that are subsequently utilized by the host,making ruminants a unique group of animals that can convert plant materials indigestible by humans into high-quality animal protein as meat and milk.Many studies using meta-omics technologies have demonstrated the relationships between rumen microbiome and animal phenotypes associated with nutrient metabolism.Recently,the causality and physiological mechanisms underpinning the host-microbiota interactions have attracted tremendous research interest among researchers.This review discusses the host-microbiota interactions and the factors affecting these interactions in ruminants and provides a summary of the advances in research on animal husbandry.Understanding the microbiota composition,the functions of key bacteria,and the host-microbiota interaction is crucial for the development of knowledge-based strategies to enhance animal productivity and host health.

Effects of Diet with"Lianhuang"Additive of Chinese Herb Medicine on Growth Performance and Metabolic Rates of Dietary Nutrients in Donglan Black Chicken

[Objectives]The study was conducted to evaluate the effects of diet with"Lianhuang"additive of Chinese herbal medicine(LACHM)on growth performance and metabolic rates of dietary nutrients in Donglan black chickens(DBCs).[Methods]80 DBCs aged 1 d were blocked into 4 groups randomly and assigned to 6 replicates in each group with 20 chicks in each replicate.Group A as control group fed basal diet.Groups B,C and D as treatment groups consumed the basal diet added with 0.25%,0.50%and 1.00%of LACHM,respectively during the test period of 70 d.In the end of feeding test,24 DBCs with similar body weight from each group were chosen out and used for a metabolism test to determine the metabolic rates of dietary nutrients from each treatment.The metabolism test was conducted as the same design as the feeding test and the DBCs from each group were fed the same diet as previous test.[Results]The ADG of chickens in the test increased by 5.00%-9.15%(P<0.05)except the stage of 50-70 d,and the individual average body weight(IABW)at 70 d in group B also increased by 4.86%(P<0.05).Compared with group A,the ADG of group C in the stages of 36-49,1-49 and 1-70 d and the IABW in the end of 70 d increased by 5.90%,2.66%,2.68%and 2.57%(P>0.05),respectively.The ADFI in the stage of 36-49 d from group A was 6.04%more than that from group B(P<0.01),and 5.12%and 4.13%more than those from groups C and D(P<0.05),respectively,and the ADFI of group A in the stage of 1-49 d was still 2.86%more than that from group C(P<0.05).However,no differences in ADFI were found in other stages in the test among the 4 groups(P>0.05).The F/G in the stages of 22-35 and 1-70 d from group B was 6.32%and 3.41%lower than those from group A(P<0.05),respectively,and even 11.43%and 7.31%lower in the stages of 36-49 and 1-49 d from group B than those from group A(P<0.01),respectively.The F/G of group C in the stage of 36-49 d was also 10.15%lower than that of group A(P<0.05),and still 5.29%lower than that from group A in 1-49 d(P<0.01),but no differences were found in other stages between the two groups(P>0.05).The metabolic rates of MD,CP,CF,NFE,CA,TE,Ca and P in the 3 treatment diets for group B,C and D all increased to some extent.Among them,the increasing extents of diets with 0.25%and 0.50%of LACHM for groups B and C were much greater.Therefore,the diet with 0.25%of LACHM could improve the growth performance and metabolic rates of dietary nutrients in DBCs significantly.[Conclusions]This study provides a theoretical reference for the effects of traditional Chinese medicine additives on the growth and metabolic rates of DBCs.

Identification of gut microbes associated with feed efficiency by daily-phase feeding strategy in growing-finishing pigs

Feed efficiency is one of the most important issues for sustainable pig production.Daily-phase feeding(DPF)is a form of precision feeding that could improve feed efficiency in pigs.Gut microbiota can regulate host nutrient digestion,absorption,and metabolism.However,which key microbes may play a vital role in improving the feed efficiency during DPF remains unclear.In the present study,we used a DPF program compared to a three-phase feeding(TPF)program in growing-finishing pigs to investigate the effects of gut microbiota on feed efficiency.A total of 204 Landrace×Yorkshire pigs(75 d)were randomly assigned into 2 treatments.Each treatment was replicated 8 times with 13 to 15 pigs per replicate pen.Pigs in the TPF group were fed with a commercial feeding program that supplied fixed feed for phasesⅠ,Ⅱ,andⅢ,starting at 81,101,and 132 d of age,respectively,and pigs in the DPF group were fed a blend of adjacent phase feed from 81 to 155 d at a gradual daily ratio and phaseⅢfeed from 155 to 180 d of age.Daily feed intake and body weight were recorded by a computerized device in the feeders.Feces and blood samples were collected from 1 pig per replicate at 155 and 180 d of age.The results showed that the DPF program remarkably improved the feed efficiency at 155 d(P<0.001)and 180 d of age(P<0.001),with a significant reduction of the intake of crude protein(P<0.01),net energy(P<0.001),crude fiber(P<0.001),ether extract(P<0.01),and ash(P<0.001).The daily-phase feeding program increased the abundance of Prevotella copri(P<0.05)and Paraprevotella clara(P<0.05),while it decreased the abundance of Ocilibacter(P<0.05)at 155 d of age.The results of correlation analysis indicated that the differentially abundant microbiota communities were closely associated with 20 metabolites which enriched amino acid and phenylalanine metabolism.Our results suggest that 2 key microbes may contribute to feed efficiency during daily-phase feeding strategies in pigs.

The adaptive strategies of yaks to live in the Asian highlands

The yak(Bos grunniens),an indigenous herbivore raised at altitudes between 3,000 and 5,000 m above sea level,is closely linked to more than 40 ethnic communities and plays a vital role in the ecological stability,livelihood security,socio-economic development,and ethnic cultural traditions in the Asian highlands.They provide the highlanders with meat,milk,fibres,leather and dung(fuel).They are also used as pack animals to transport goods,for travel and ploughing,and are important in many religious and traditional ceremonies.The Asian highlands are known for an extremely,harsh environment,namely low air temperature and oxygen content and high ultraviolet light and winds.Pasture availability fluctuates greatly,with sparse pasture of poor quality over the long seven-month cold winter.After longterm natural and artificial selections,yaks have adapted excellently to the harsh conditions:1)by genomics,with positively selected genes involved in hypoxia response and energy metabolism;2)anatomically,including a short tongue with a weak sense of taste,and large lung and heart;3)physiologically,by insensitivity to hypoxic pulmonary vasoconstriction,maintaining foetal haemoglobin throughout life,and low heart rate and heat production in the cold season;4)behaviourlly,by efficient grazing and selecting forbs with high nutritional contents;5)by low nitrogen and energy requirements for maintenance and low methane emission and nitrogen excretion,namely,‘Low-Carbon’and‘Nitrogen-Saving’traits;6)by harboring unique rumen microbiota with a distinct maturation pattern,that has coevolved with host metabolism.This review aims to provide an overview of the comprehensive adaptive strategies of the yak to the severe conditions of the highlands.A better understanding of these strategies that yaks employ to adapt to the harsh environment could be used in improving their production,breeding and management,and gaining benefits in ecosystem service and a more resilient livelihood to climate change in the Asian highlands.

Identification of MBF2 family genes in Bombyx mori and their expression in different tissues and stages and in response to Bacillus bombysepticus infection and starvation

The Multiprotein bridge factor 2 （MBF2） gene was first identified as a coactivator involved in BmFTZ-F 1-mediated activation of the Fushi tarazu gene. Herein, nine homologous genes of MBF2 gene are identified. Evolutionary analysis showed that this gene family is insect-specific and that the family members are closely related to response to pathogens （REPAT） genes. Tissue distribution analysis revealed that these genes could be expressed in a tissue-specific manner. Developmental profiles analysis showed that the MBF2 gene family members were highly expressed in the different stages. Analysis of the expression patterns of nine MBF2 family genes showed that Bacillus bombysepticus treatment induced the up-regulation of several MBF2 family genes, including MBF2-4, -7, -9, -8. Furthermore, we found the MBF2 family genes were modulated by starvation and the expression of these genes recovered upon re-feeding, except for MBF2-5, -9. These findings suggested roles for these proteins in insect defense against pathogens and nutrient metabolism, which has an important guiding significance for designing pest control strategies.