Abstract:As a major tropical fruit worldwide,the processing of pineapple pomace accounting for 50%to 60%of the whole fruit mass.Improper disposal may lead to environmental pollution and resource waste.Pineapple pomace is rich in various bioactive components such as dietary fiber(DF),bromelain,phenolics,and polysaccharides,exhibiting multiple biological functions including immunomodulatory,antioxidant,anti-inflammatory,antibacterial,antitumor,and antiviral activities.In animal production,after ensiling or fermentation treatment,pineapple pomace can serve as a high-quality unconventional feed.Adding pineapple pomace to the diet of ruminants helps regulate rumen fermentation and improves growth performance,milk yield,and meat quality.In monogastric animals,appropriate inclusion can enhance nutrient utilization and intestinal health in pigs,as well as improve immune function and meat quality in poultry.In aquatic animals,it can increase digestibility,boost immunity,and reduce aquaculture pollution in fish.However,the high-value utilization of pineapple pomace still faces technical bottlenecks such as low lignocellulose degradation efficiency,lack of high value-added products,and incomplete evaluation systems for biological efficacy.Future efforts should focus on developing efficient biodegradation technologies,establishing comprehensive quality evaluation and control systems,and building an industry-university-research collaborative industrial chain model to fully exploit the feeding potential of pineapple pomace.This article reviews the nutritional characteristics of pineapple pomace,the biological activities of its extracts,and its application in animal production,aiming to provide references for promoting its high-value utilization as feed.

Abstract:This experiment aimed to investigate the effects of in ovo amniotic cavity injection with Lactobacillus salivarius XP132 on the immune function and intestinal microbiota of layer chicks.A total of 150 SPF laying chicken eggs were selected and randomly divided into two groups,with three replicates per group and 25 eggs per replicate.Group DZ was injected with 0.2 mL of sterile physiological saline into the amniotic cavity at 18 days of embryonation.Group MY was injected with 0.2 mL of a Lactobacillus salivarius XP132 suspension containing 1.21×108 CFU/mL via the amniotic cavity at 18 days of embryonation.The incubation period was 21 days,and the feeding period was 35 days.The results showed that compared to group DZ,serum level of interleukin-2(IL-2)in the group MY was significantly increased at 14,21,and 28 days of age(P<0.05),and significantly increased the levels of interleukin-4(IL-4),interleukin-6(IL-6),and interferon-γ(IFN-γ)at 7,14,and 21 days of age(P<0.05).The number of immunoglobulin A-positive cells(IgA+cells)in the duodenum and ileum at 21 and 35 days of age was significantly increased in group MY(P<0.05),and the number of IgA+cells in the jejunum at 7 and 21 days of age was significantly increased(P<0.05).At 7 and 21 days of age,the Shannon index and Chao1 index in group MY were significantly higher than in the group DZ(P<0.05),and the Simpson index was significantly lower than in the group DZ(P<0.05).At 7 days of age,the relative abundances of Lactobacillus and Oscillospira in group MY were higher than in the group DZ,while the relative abundance of Shigella was lower than in the group DZ.At 21 days of age,the relative abundance of Lactobacillus in group MY was higher than in the group DZ,and the relative abundance of Shigella was lower than in the group DZ.At 35 days of age,the relative abundance of Shigella in group MY was lower than in the group DZ.The study shows that in ovo amniotic injection of Lactobacillus salivarius XP132 can enhance the immune function and improve the diversity of cecal microbiota of layer chicks.

Abstract:This study aimed to establish a high-performance liquid chromatography method for the determination of β-nicotinamide mononucleotide(NMN)content in eggs.The chromatographic conditions were as follows:A Shimadzu Inert Sustain AQ-C18 column(4.6 mm×250.0 mm,5 μm)was used,with a mobile phase consisting of 10 mmol/L ammonium acetate aqueous solution and acetonitrile(95∶5)under isocratic elution.The flow rate was 0.5 mL/min,the column temperature was 35℃,the detection wavelength was 220 nm,and the injection volume was 5 μL.The results showed that NMN exhibited a good linear relationship within the range of 15 to 500 mg/L,with a correlation coefficient(R2)of 0.999 5.The limit of detection and limit of quantification were 12 mg/L and 30 mg/L,respectively.In methodological validation,the average spike recovery rates for egg white samples ranged from 90%to 98%,with a relative standard deviation(RSD)of 4.60%～12.76%.For egg yolk samples,the average recovery rates ranged from 84%to 88%,with RSD of 3.05%to 5.35%.The RSD for precision and stability tests were 0.29%and 0.63%,respectively.The study shows that the established method exhibits strong specificity,and its precision and stability meet the required standards,making it suitable for the rapid and accurate determination of NMN content in eggs.

Abstract:Against the backdrop of the'dual carbon'strategy,pig breeding industry as an important part of Chinese livestock husbandry,could play a significant role in ensuring food security and promoting farmers'income growth by enhancing its production efficiency.Based on the panel data of 25 provinces in China from 2008 to 2024,this article constructed a difference-in-differences model to empirically examine the impact of low-carbon policies on the efficiency of pig breeding.The results showed that the implementation of low-carbon policies was conducive to improving the efficiency of pig breeding,and this conclusion remains valid after passing the parallel trend test and a series of robustness tests.The mechanism test indicated that low-carbon policies promoted the efficiency of pig breeding through technological innovation.The study shows that promoting the low-carbon and efficient development of pig breeding,as well as promoting technological innovation and dissemination in pig breeding,can help the livestock industry transform towards a high-quality and sustainable direction.

Abstract:This experiment aimed to analyze the nutritional composition of muscle tissue from different size classes of six fish species,Cranoglanis bouderius,Squaliobarbus curriculus,Xenocypris davidi,Spinibarbus hollandi,Ptychidio jordani,and Acrossocheilus longipinnis.Biochemical analysis methods were employed to determine and evaluate the conventional nutritional components,amino acid profiles,and fatty acid compositions of muscle tissue from wild-caught specimens.The results showed that regarding conventional nutritional components,Spinibarbus hollandi is a high-protein(19.30%to 21.44%),low-fat fish species.Cranoglanis bouderius had the lowest protein content,while Ptychidio jordani exhibited a relatively high fat content.Regarding amino acid composition,the total amino acid content in the muscle of the six species ranged from 16.57%to 23.11%,with higher levels of glutamic acid,aspartic acid,and lysine.The first limiting amino acid was methionine+cystine.The essential amino acid index(EAAI)ranged from 0.53 to 0.96.Acrossocheilus longipinnis had a relatively low EAAI,indicating poorer amino acid balance and nutritional value.In contrast,large-sized Spinibarbus hollandi showed a higher EAAI,suggesting better amino acid balance and superior nutritional value.Analysis detected 21 to 25 fatty acids in the muscle tissue of the six species.The fatty acid content in the muscle of large-sized fish was generally higher than that in small-sized fish.The study shows that based on a comprehensive comparison,Acrossocheilus longipinnis has relatively lower nutritional value.The other species are more nutritious and have higher health value.

Abstract:This experiment aimed to investigate the effects of dietary supplementation with Artemisia ordosica on the fatty acid composition in adipose tissues of cashmere goats.A total of 40 aged four months weaned castrated male lambs with similar body weight and condition were randomly divided into two groups,with four replicates per group and five lambs per replicate.Control group(group CON)was fed a basal diet,while Artemisia ordosica group(group ARO)received the basal diet in which 3%Artemisia ordosica replaced an equal proportion of the mixed roughage.The pre-test period was 14 days,and the formal trial period was 90 days.The results showed that compared with the group CON,the concentrations of n-3 polyunsaturated fatty acids(n-3 PUFA)and n-6 polyunsaturated fatty acids(n-6 PUFA)such as C20∶5n-3 and C18∶3n-6 in renal lipid,omental lipid and mesenteric lipid of cashmere goats in the group ARO were significantly increased(P<0.05).The content of saturated fatty acids(SFA)in each adipose tissue,and the ratio of n-6 PUFA to n-3 PUFA in omental fat and mesenteric fat were significantly decreased(P<0.05).The study shows that Artemisia ordosica can improve the fatty acid composition in the adipose tissues of cashmere goats,increase the concentrations of n-3 PUFA和n-6 PUFA,and improve the quality and flavor of adipose.

Abstract:Gynostemma pentaphyllum is a traditional medicinal and edible plant in China,rich in various bioactive components such as saponins,polysaccharides,and flavonoids.Among these,Gynostemma saponins and polysaccharides are recognized as its primary core pharmacological active substances.Modern pharmacological research has confirmed that Gynostemma pentaphyllum possesses multiple physiological functions,including antioxidant,immunomodulatory,lipid-regulating,hypoglycemic,and organ-protective effects.In recent years,with the increasing restrictions on antibiotic use in the livestock industry,Gynostemma pentaphyllum has emerged as a green and safe feed additive with broad application prospects in animal production.It not only promotes animal health and improves the quality of livestock products,but also contributes to the green and sustainable development of the animal husbandry sector,representing a promising feed additive.This article reviews the main bioactive components and biological functions of Gynostemma pentaphyllum,with a focus on summarizing research progress in its application in pig,poultry,and ruminant production,including its beneficial effects on animal growth performance,product quality,and immune function.The aim is to provide a reference for the rational application of Gynostemma pentaphyllum in animal production.

Abstract:This experiment aimed to investigate the effects of dietary supplementation with Schizochytrium sp.meal on the production performance,egg quality,serum biochemical indices,and apparent metabolic rate of nutrients in laying hens.A total of 384 healthy 37-week-old Jingfen No.6 laying hens with similar body weight were randomly divided into four groups,with six replicates per group and 16 hens per replicate.Control group(group CON)was fed a basal diet,while the experimental groups Ⅰ,Ⅱ,and Ⅲ were fed the basal diet supplemented with 0.4%,0.6%,and 0.8%Schizochytrium sp.meal,respectively.The pre-trial period was one week,and the formal trial period was eight weeks.The results showed that compared with the group CON,eggshell strength was significantly increased in the group Ⅲ(P<0.05).Serum high-density lipoprotein cholesterol(HDL-C)content was significantly elevated(P<0.05),while triglyceride(TG)content and alanine aminotransferase(ALT)activity were significantly reduced(P<0.05)in group Ⅲ,The docosahexaenoic acid content in egg yolks was significantly higher in the group Ⅲ(P<0.05).The study shows that dietary supplementation with 0.8%Schizochytrium sp.meal can effectively improve egg quality,serum biochemical indices,and fatty acid composition in eggs.

Abstract:As a major by-product of the sea buckthorn industry,sea buckthorn leaves are rich in various bioactive substances such as flavonoids,polyphenols,polysaccharides,and tannins.They exhibit antioxidant,anti-inflammatory,immune-regulating,and gut health-improving functions,making them a novel green feed additive with development potential.This article reviews the efficient extraction process for active ingredients from sea buckthorn leaves,covering both traditional methods and modern technologies such as ultrasound-assisted,microwave-assisted,enzymatic,and supercritical fluid extraction.It also summarizes the application effects of sea buckthorn leaves in poultry,swine,and ruminant production,and further explores the antioxidant and anti-inflammatory molecular mechanisms based on key signaling pathways such as nuclear factor E2-related factor 2/antioxidant response element(Nrf2/ARE)and nuclear factor kappa B(NF-κB),as well as the mechanism of promoting gut health by regulating gut microbiota and enhancing gut barrier function.Finally,addressing current challenges in the feed application of sea buckthorn leaves,such as low standardization of raw materials,high extraction costs,insufficiently in-depth mechanistic studies,and inadequate regulatory standards,the article prospects future research directions.These include breeding specialized resources,developing green and low-carbon extraction processes,constructing precise nutritional regulation models,and promoting data-driven applications.This review aims to provide references for the high-value utilization of sea buckthorn leaf resources and the sustainable development of animal husbandry.

Abstract:The problem of mycotoxin contamination in feed and its raw materials is becoming increasingly serious,posing a continuous threat to the economic development of the livestock industry and the health of animals.Therefore,it is of vital importance to develop green and efficient degradation technologies.Photocatalytic degradation technology boasts the advantages of being green and safe,simple and efficient,as well as low-cost,making it particularly promising for the degradation of pollutants such as mycotoxins.This article explains the principle of photocatalytic technology,summarizes the types and characteristics of common photocatalytic materials,and focuses on the research progress regarding the use of this technology to degrade mycotoxins in feed and ingredients,it examines the application challenges and future development trends of photocatalytic technology in the feed industry,with the aim of providing a reference for the rapid and safe degradation of mycotoxins in feed.

Abstract:This experiment aimed to investigate the effects of alkaline mineral complexes(AMC)on the growth performance,nutrient apparent digestibility,and serum indices in fattening cattle.A total of 30 Hereford cattle,exhibiting comparable body condition and body weight,were randomly divided into two groups,with 15 replicates per group,and one cattle per replicate.The control group(group CON)was fed a basic diet,while the group AMC was supplemented with 10 g/(head·d)of AMC.The pre-test period was 14 days,and the formal test period was 60 days.The results showed that compared with group CON,the average daily gain(ADG)of the group AMC was significantly increased(P<0.05),and the feed-to-gain ratio(F/G)was significantly decreased(P<0.05).The apparent digestibility of dry matter(DM)in the group AMC was significantly higher than that in the group CON(P<0.05).The levels of immunoglobulin A(IgA),immunoglobulin G(IgG),immunoglobulin M(IgM),interleukin-2(IL-2),and interleukin-4(IL-4)in the group AMC were significantly higher than those in the group CON(P<0.05),while the levels of tumor necrosis factor-α(TNF-α)and interferon-γ(IFN-γ)were significantly lower than those in the group CON(P<0.05).The total antioxidant capacity(T-AOC),and the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and catalase(CAT)in the group AMC were significantly higher than those in the group CON(P<0.05),while the malondialdehyde(MDA)content was significantly lower than that in the group CON(P<0.05).The study shows that AMC can improve the growth performance,and enhance the body's antioxidant capacity and immune function of fattening cattle.

Abstract:This experiment aimed to compare the effects of formula feed and feed fish(Cirrhinus mrigala)on the growth performance,serum biochemical indices,and muscle quality of hybrid mandarin fish(Siniperca scherzeri♂×Siniperca chuatsi♀).A total of 600 juvenile mandarin fish with similar initial body weight were selected and randomly divided into two groups with three replicates per group and 100 fish per replicate.They were fed either formula feed(formula feed group)or feed fish(feed fish group).The pre-trial period lasted for one week,and the formal trial period lasted for eight weeks.The results showed that the survival rate in the formula feed group was significantly higher than that in the feed fish group(P<0.05).There were no significant differences in final body weight,weight gain rate,feed conversion ratio,hepatosomatic index,viscerosomatic index,and condition factor between the two groups(P>0.05).Serum glucose and triglyceride levels in the formula feed group were significantly higher than those in the feed fish group(P<0.05),while the levels of total protein,albumin,globulin,total cholesterol,high-density lipoprotein,low-density lipoprotein,and the activity of aspartate aminotransferase were significantly lower than those in the feed fish group(P<0.05).Lipid droplet area and proportion of hepatocytes in the formula feed group were significantly lower than those in the feed fish group(P<0.05).The muscle fiber diameter in the formula feed group was significantly lower than that in the feed fish group(P<0.05).Six texture profile analysis indices were also lower to varying degrees in the formula feed group,only cohesiveness showed a significant difference(P<0.05).The study shows that using formula feed instead of feed fish to breed hybrid mandarin fish does not affect its growth performance and physical indices,and can effectively improve liver health and increase survival rate.However,the muscle quality still lags behind that of fish raised with feed fish.

Abstract:As an important type of feed microbial additive,Bacillus plays a key role in improving the nutritional quality of silage and promoting its high-value utilization.Bacillus can stimulate the growth of lactic acid bacteria(LAB)by secreting antimicrobial substances and cellulases,which inhibit spoilage microorganisms,degrade cellulose,and provide carbon sources for LAB.This accelerates lactic acid(LA)accumulation,lowers pH value,and shortens the fermentation period.Additionally,Bacillus possesses auxiliary fiber-degrading functions,enabling it to hydrolyze plant cell walls to release soluble sugars and degrade phytic acid,thereby enhancing the utilization efficiency of silage.Furthermore,Bacillus can secrete lipopeptides to suppress molds and yeasts,and degrade mycotoxins through enzymatic degradation,metabolic transformation,and microbial competition,thereby improving aerobic stability.Bacillus also contributes to the degradation of nitrites and reduces the accumulation of ammonia nitrogen(NH3-N).This article reviews relevant studies on the effects of various Bacillus species,such as Bacillus subtilis(BS),Bacillus licheniformis(BL),Bacillus velezensis(BV),and Bacillus amyloliquefaciens(BA),on the nutritional quality of silage,aiming to provide references for further research and development in this field.

Abstract:This study aimed to enhance the protection and management of musk animals from the perspective of feed nutrition.Eleven species of wild forage plants preferred by musk deer in the Ganzi Tibetan Autonomous Prefecture were selected as subjects.Their main nutritional components were determined,and a comprehensive evaluation was conducted using the grey relational grade method.The results showed that the crude protein(CP)content of the plants ranged from 6.21%to 19.54%.Among them,the CP content of Hippophae rhamnoides L.(19.54%)was significantly higher than that of other plants(P<0.05).Pyracantha,Rubus spp.,and Xinjiang Lonicera tatarica L.exhibited relatively high crude fat(EE)content.Viburnum spp.had a relatively high crude fiber(CF)content.Lonicera chrysantha Turcz.showed the highest crude ash(Ash)content(8.89%).The nitrogen-free extract(NFE)content of Cunninghamia lanceolata(Lamb.)Hook(57.91%)was significantly higher than that of other plants(P<0.05).The total phosphorus(TP)content was low across all plants(0.03%to 0.06%).Nutritional type analysis indicated that the plants were primarily of the low-ash,nitrogen-carbon type.The grey relational grade evaluation revealed that only sea-buckthorn achieved a high comprehensive correlation coefficient(equal-weighted correlation=0.844 0),classifying its nutritional value as'excellent'.The study shows that Hippophae rhamnoides L.possesses the most favorable conventional nutritional components and comprehensive nutritional value,making it a high-quality plant resource with development potential.Considering the comprehensiveness of nutrients,none of the 11 plant species studied are suitable as a sole feed source for musk deer.

Abstract:Digital transformation serves as a critical pathway for feed enterprises to enhance their market competitiveness.Research and development investment intensity as the core driver for achieving technological innovation,product upgrades,and business model innovation in feed enterprises,exerting a decisive influence on their digital transformation process.Based on panel data from Chinese A-share listed feed enterprises from 2013 to 2023,this paper empirically examines the mechanism through which research and development intensity affects the digital transformation of feed enterprises.The results showed that research and development investment intensity significantly promoted the digital transformation process of feed enterprises,and this conclusion remained valid after robustness test.Heterogeneity analysis indicated that the promoting effect of research and development investment intensity on the digital transformation of feed enterprises was more pronounced in state-owned enterprises and high-productivity enterprises.The study shows that research and development investment intensity primarily promotes the digital transformation of feed enterprises through two pathways:Accelerating the accumulation of human capital and enhancing the level of technological innovation.

Abstract:This experiment aimed to investigate the effects of substituting basal diet with different proportions of arborvitae seeds on the growth performance and meat quality of Lüliang black goats.A total of 120 Lüliang black goats(half male and half female)in the fattening period with an initial body weight of(30.00±2.20)kg were selected and randomly divided into four groups,with three replicates per group and 10 goats per replicate.The control group was fed a basal diet,while the substitution groups replaced the basal diet with equal amounts of 10％(group A),20％(group B),and 30％(group C)of arborvitae seeds,respectively.The pre-test period was seven days,and the formal test period was 30 days.The results showed that compared with the control group,group B achieved the highest final weight and average daily gain(ADG).The average daily feed intake(ADFI)and feed-to-gain ratio(F/G)were significantly reduced in substitution groups(P＜0.05).The carcass weight,carcass fat content(GR value),backfat thickness,and eye muscle area were significantly increased in the substitution groups(P＜0.05).Serum total protein(TP)and albumin(ALB)levels were significantly increased in the substitution groups(P＜0.05),while alanine aminotransferase(ALT)and aspartate aminotransferase(AST)activities,as well as urea nitrogen(BUN)and total cholesterol(TC)levels were significantly decreased(P＜0.05).Energy and cholesterol levels in the substitution groups were reduced,while protein and various mineral elements(sodium,calcium,iron,zinc,selenium)levels were increased.Iron and zinc levels differed significantly among substitution groups(P＜0.05).There was no significant differences in isoleucine,threonine,and methionine concentrations among groups(P＞0.05).Serine,valine,tyrosine,and glutamic acid levels were significantly increased in groups B and C(P＜0.05).Glycine,alanine,and lysine levels were significantly increased in the substitution groups(P＜0.05),while aspartic acid,histidine,leucine,and phenylalanine levels were significantly decreased(P＜0.05).The study shows that under the condition of replacing 20％of the basal diet with arborvitae seeds,the growth performance,slaughter performance and meat quality of Lüliang black goats can be improved.

Abstract:This experiment aimed to investigate the effects of tributyrin on the growth performance,diarrhea,and inflammatory cytokine levels in weaned piglets.A total of 240 aged 28 days' Duroc × Landrace × Yorkshire' weaned piglets with similar body weights were randomly divided into four groups,with six replicates per group and 10 piglets per replicate.The control group was fed a basal diet,while the experimental groups were supplemented with 0.1％(group 0.1),0.2％(group 0.2),and 0.4％(group 0.4)tributyrin in the basal diet,respectively.The pre-test period was seven days,and the formal test period was 28 days.The results showed that compared with the control group,the weight gain and average daily gain of the group 0.2 were significantly increased(P＜0.05),the feed-to-gain ratio was significantly reduced(P＜0.05).The diarrhea rate was extremely reduced in the experimental groups(P＜0.01),and the diarrhea index was significantly reduced in groups 0.2 and 0.4(P＜0.05).The D-l act ate content in the serum was extremely decreased in groups 0.2 and 0.4(P＜0.01),diamine oxidase activity was significantly decreased(P＜0.05),and tumor necrosis factor-αcontent was significantly reduced(P＜0.05).The interleukin-6 content in the serum was extremely decreased in group 0.2(P＜0.01).The interleukin-10 content in the serum was extremely increased in the experimental groups(P＜0.01).The mRNA relative expression levels of interleukin-6,interleukin-1β,and tumor necrosis factor-α in the jejunum were significantly decreased in groups 0.2 and 0.4(P＜0.05),while the mRNA relative expression of interleukin-10 in the jejunum was significantly increased in the experimental groups(P＜0.05).The study shows that dietary supplementation with an appropriate amount of tributyrin can improve growth performance,reduce the diarrhea rate,and alleviate systemic inflammatory responses in weaned piglets.The optimal supplementation level of tributyrin is 0.2％.

Abstract:This experiment aimed to investigate the optimal processing parameters for extrusion puffing Cyperus esculentus meal pellets feed and its effects on the growth performance and serum biochemical indexes in finishing pigs.Using Cyperus esculentus meal as the raw material and gelatinization degree as the evaluation index,the extrusion parameters were optimized by response surface methodology.A total of 120 finishing pigs were randomly allocated into four groups with three replicates per group,and 10 pigs per replicate.The groups were fed experimental diets containing 0(Group A),5％(Group B),10％(Group C),and 15％(Group D)of extrusion puffing Cyperus esculentus meal,respectively.The pre-test period was seven days,and the formal test period was 56 days.The results showed that the optimal extrusion parameters for Cyperus esculentus meal pellets feed were as follows:Material moisture content 22％,screw speed 320 r/min,and zone Ⅲ temperature in extrusion 172 ℃.Under these conditions,the gelatinization degree of the pellets feed reached 90.93％.Compared with Group A,the average daily gain(ADG)of Group C was significantly increased(P＜0.05),while the feed-to-gain ratio(F/G)was significantly decreased(P＜0.05).The serum total protein and albumin concentrations in Groups B,C,and D were significantly increased(P＜0.05),while the urea nitrogen content,alanine aminotransferase,and aspartate aminotransferase activities were significantly decreased(P＜0.05).The study indicates that the inclusion of 10％extrusion puffing Cyperus esculentus meal pellets feed in the diet can improve the growth performance and serum biochemical indexes of finishing pigs.

Abstract:This study aimed to investigate the effects of supplemented with Enterococcus faecalis t3 in high-starch diet on the growth performance,serum biochemical indices,and hepatic glucose and lipid metabolism of Micropterus salmoides.A total of 225 healthy Micropterus salmoides with an initial body weight of(5.46±0.01)g were randomly divided into three groups,with three replicates per group and 25 fish per replicate.Control group(group CON)was fed a high-starch basal diet.Experimental groups were fed the high-starch basal diet supplemented with 0.12％(group E1)and 1.18％(group E2)of Enterococcus faecalis t3,respectively.The pre-test period was two weeks and the formal test period was eight weeks.The results showed that compared with group CON,the final body weight,weight gain rate(WGR),specific growth rate(SGR),protein efficiency ratio(PER),and condition factor(CF)in groups E1 and E2 were significantly increased(P＜0.05),while the feeding rate(FR)and viscerosomatic index(VSI)were significantly decreased(P＜0.05).The hepatosomatic index(HSI)in group E2 was significantly reduced(P＜0.05).Serum glucose(GLU)content in group E2 was significantly lower(P＜0.05).The concentrations of triglycerides(TG),total cholesterol(TC),and D-lactic acid(LD),as well as the activities of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)in groups E1 and E2 were significantly decreased(P＜0.05),and acid phosphatase(ACP)activity was significantly increased(P＜0.05).The alkaline phosphatase(AKP)activity in group E2 was significantly increased(P＜0.05).Hepatic glycogen content and the activities of phosphofructokinase(PFK),fatty acid synthase(FAS),and acetyl-CoA carboxylase(ACC)in the liver of groups E1 and E2 were significantly decreased(P＜0.05).Dietary supplementation with Enterococcus faecalis t3 improved the histological structure of the liver and intestine in Micropterus salmoides.The study shows that supplemented with Enterococcus faecalis t3 in a high-starch diet can regulate hepatic glucose and lipid metabolism,improve liver and intestinal health,thereby enhancing growth performance and feed utilization efficiency in Micropterus salmoides.When the supplementation amount of Enterococcus faecalis t3 is 1.18％,the overall effect is better.

Abstract:This experiment aimed to investigate the effects of applying rhizobia and ARC microbial agent under nitrogen reduction conditions on the agronomic traits,yield,quality,and economic benefits of soybeans.Using the cultivar Henong 71 as material,four nitrogen levels were established based on the conventional nitrogen application rate(T9,control):100％nitrogen reduction(N0),40％nitrogen reduction(N60),20％nitrogen reduction(N80),and no nitrogen reduction(N100).Each nitrogen level was combined with either rhizobia strain 59+ARC or rhizobia strain 17+ARC,resulting in a total of nine treatments.The results showed that compared to rhizobia strain 59,the combined application of rhizobia strain 17 and ARC had a more significant promoting effect on Henong 71.Under the T7 treatment(rhizobia strain 17+N60+ARC),the comprehensive performance of agronomic traits such as plant height,stem diameter,relative value of chlorophyll content(SPAD value),aboveground dry weight,and nodule fresh weight was better.The T7 treatment yielded the highest number of pods per plant,seeds per plant,and seed weight per plant,which increased by 18.85％,20.48％,and 9.89％,respectively,compared to the T9 treatment.It also achieved the highest economic benefit,with a net profit of 1 664.22 yuan/hm2,an increase of 1 113.84 yuan/hm2 over T9 treatment.As the nitrogen application rate decreased,the protein content of each treatment showed a increase followed by a decrease,while the fat content gradually declined.The protein and fat content of the T7 treatment were lower than in the T9 treatment(decreased by 0.44％and 1.49％,respectively)(P＞0.05).The T5 treatment had the best soybean seed quality.The study shows that applying rhizobia strain 17 and ARC microbial agent under 20％to 40％nitrogen reduction conditions can achieve favorable agronomic and yield performance,higher economic benefits,and maintain good soybean seed quality.