This study aimed to investigate the effects of different protein and energy levels of diets on growth performance,nutrient apparent digestibility and serum biochemical indexes of fattening yaks in shelter feeding.A total of 90 male yaks with good body condition and similar age and body weight(180.00±11.67)kg were randomly divided into 9 groups with 10 yaks per group.Three levels were set for each factor,namely 3 protein levels of low(12.5％),medium(15.5％),and high(18.5％),as well as 3 comprehensive net energy levels of low(6.5 MJ/kg),medium(7.5 MJ/kg),and high(8.5 MJ/kg),9 different total mixed diets(TMR)were designed with 3 protein levels multiplied by 3 energy levels,with each TMR fed to 1 experimental group in the pretest period of 20 days and the formal trial period of 90 days.Results showed as follows:1)protein level had no significant effect on growth performance indexes(P＞0.05),while net energy level had significant effects on the total weight gain(TWG)and average daily gain(ADG)(P＜0.05),and had an extremely sig-nificant effect on ratio of feed to gain(F/G)(P＜0.01);the interaction of protein and net energy level had significant effects on TWG,ADG and F/G(P＜0.01).2)Protein level had extremely significant effects on the digestibility of crude protein(CP)and Ash(P＜0.01),and had significant effects on the digestibility of acid detergent fiber(ADF),neutral detergent fiber(NDF)and crude fiber(CF)(P＜0.05);net energy level had a significant effect on the digestibility of Ash(P＜0.05);the interaction of 2 factors had significant effects on the digestibility of dry matter(DM)and Ash(P＜0.05).3)Protein level had an extremely significant effect on the contents of serum urea nitrogen(UN)(P＜0.01),and had significant effects on the content of phosphate(P)in serum(P＜0.05);net energy level had extremely significant effects on the contents of total protein(TP),albumin(ALB),triglyceride(TG)and total cholesterol(TC)(P＜0.01)and a significant effect on total bile acid(TBA)content in serum(P＜0.05);the interaction of 2 factors had extremely signifi-cant effects on the alkaline phosphatase(ALP)activity and UN content(P＜0.01),and had significant effects on the content of creatinine(CRE)and P(P＜0.05).In conclusion,the effects of comprehensive net energy level on growth performance of yaks is greater than that of protein level,while the effect of protein level on nu-trient apparent digestibility is greater than that of energy level.Under the conditions of this study,with the diet-ary comprehensive net energy level of 8.5 MJ/kg and protein level of 15.5％,the growth performance of fatte-ning yaks in shelter feeding is the best.[Chinese Journal of Animal Nutrition,2024,36(3):1698-1712]
Bacillus licheniformis (BL) has been widely regarded as an important growth promoter in recent years. However, its usage in animal industry still needs more foundations. The aim of our study was to study the effects of BL on the growth performance, immunity, oxidative function and intestinal flora of broilers. A total of 760 one-day-old yellow-feathered broilers were randomly divided into 4 groups with 10 replicates per group and 19 broilers per replicate. The broilers in the control group (CON) were fed with basal diet. The treatment groups were supplemented with 250 mg/kg (BL250), 500 mg/kg (BL500) and 750 mg/kg (BL750) BL in the basal diet for 70 d. Results showed that BL groups significantly increased the body weight (BW) and average daily gain (ADG), decreased average daily feed intake (ADFI) and feed conversion ratio (FCR). In addition, the spleen and bursa indexes were higher in the BL groups than that in the CON group at d 70. BL supplementation also markedly increased the levels of immunoglobulins Y (IgY), IgA and anti-inflammatory interleukin 10 (IL-10), reduced the levels of proinflammatory IL-1β, tumor necrosis factor α (TNF-α) and IL-2 in the serum at 70 d in a concentration-dependent manner. Besides, BL addition significantly increased the levels of series antioxidant enzymes including total antioxidant capacity (T-AOC), glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase (CAT), and decreased the level of malondialdehyde (MDA) in the serum. Moreover, BL groups showed an obvious increase of isobutyric acid markedly and BL500 group significantly promoted the level of isovaleric acid in cecal contents of broilers. Finally, microbial analysis showed that BL supplementation presented visual separations of microbial composition and increased the relative abundance of p_Proteobacteria, g_Elusimicrobium, and g_Parasutterella comparing with the CON group. Together, this study inferred that dietary BL supplementation improved the growth performance, immune and antioxidant functions, changed the intestinal microflora structure and metabolites of yellow-feathered broilers, which laid a good basis for the application of probiotics in the future.
本试验通过研究饲粮中添加不同水平氨基酸锰络合物对5～10周龄武冈铜鹅生长性能、屠宰性能、器官指数、血清生化指标和肝脏脂质代谢指标的影响,旨在确定其在饲粮中的适宜添加水平.选用28日龄武冈铜鹅300只,随机分为6组,每组5个重复,每个重复10羽(公母各占1/2).对照组饲喂基础饲粮,各试验组(Ⅰ组～Ⅴ组)分别在基础饲粮中添加20、40、60、80和100 mg/kg的氨基酸锰络合物(以锰元素计).试验期42 d.结果表明:1)与对照组相比,饲粮添加氨基酸锰络合物对试验鹅生长性能、屠宰性能和器官指数均无显著影响(P＞0.05).2)与对照组相比,Ⅱ组和Ⅲ组血清高密度脂蛋白(HDL)含量显著提高(P＜0.05),Ⅱ组～V组血清尿酸(UA)含量显著降低(P＜0.05).3)与对照组相比,各试验组肝脏脂肪酸合成酶(FAS)活性均显著提高(P＜0.05),1组肝脏脂蛋白脂肪酶(LPL)活性显著提高(P＜0.05),Ⅰ组～Ⅳ组肝脏乙酰辅酶A羧化酶(ACC)活性显著提高(P＜0.05).4)以肝脏FAS、LPL和ACC活性作为评价指标,通过二次曲线模型估测得出武冈铜鹅饲粮中有机锰适宜添加水平为50.39～53.67 mg/kg.综上可知,饲粮添加氨基酸锰络合物对5～10周龄武冈铜鹅生长性能、屠宰性能和器官指数无显著影响,但适宜水平的有机锰能够改善血清生化指标,调控机体脂质代谢.
本试验旨在研究脱脂黑水虻幼虫粉替代饲料中不同比例鱼粉对中华鳖稚鳖生长性能、肝脏抗氧化指标、肝脏和肠道消化酶活性、肠道组织形态和菌群的影响.配制5种等氮等脂的试验饲料,5种试验饲料中脱脂黑水虻幼虫粉替代鱼粉的比例分别为0(F0,作为对照)、15％(F15)、30％(F30)、45％(F45)、60％(F60).选取初始体重为(4.98±0.18)g 的中华鳖稚鳖 175只,随机分为5组,每组5个重复,每个重复7只,进行为期8周的养殖试验.结果显示:脱脂黑水虻幼虫粉替代饲料中不同比例的鱼粉对中华鳖稚鳖的摄食量、体比系数和肝体指数没有显著影响(P＞0.05).与对照组相比,F15、F30和F45组的终末体重、成活率、增重率和特定生长率均没有显著变化(P＞0.05),F60组则显著降低(P＜0.05);F15和F45组的饲料系数没有显著变化(P＞0.05),F30和F60组则显著升高(P＜0.05);F45和F60组的脂体指数显著降低(P＜0.05).各组间血清总蛋白、白蛋白、球蛋白和乳酸含量以及谷丙转氨酶、谷草转氨酶和碱性磷酸酶活性均无显著差异(P＞0.05);F45组血清酸性磷酸酶活性显著高于对照组(P＜0.05).F30组肝脏抗氧化酶和消化酶活性最高,F45组肠道淀粉酶和脂肪酶活性最高.高通量测序分析显示,F30组肠道中邻单胞菌属的相对丰度最低,鲸杆菌属的相对丰度较高,但是与对照组没有显著差异(P＞0.05);各组在门和属水平上的优势菌群相同,肠道菌群alpha多样性指数无显著差异(P＞0.05).综上所述,脱脂黑水虻幼虫粉替代饲料中30％～45％的鱼粉对中华鳖稚鳖的生长性能没有产生负面影响,并能改善肝脏抗氧化能力与肠道菌群结构.
This experiment was conducted to investigate the effects of dietary Cinnamomum longepaniculatum leaves on growth performance,slaughter performance,muscle quality,organ indices and serum biochemical indices of meat rabbits. A total of 120 New Zealand white rabbits of 30-day-old weaned at the same time with close body weight and good health were randomly divided into 4 groups with 5 replicates per group and 6 white rabbits per replicate（half male and half female）. Meat rabbits in the 4 groups were fed the basal diet supplemented with 0（control group）,3%,6% and 12% Cinnamomum longepaniculatum leaves,respectively. The pre-trial period lasted for 7 days and the experimental period lasted for 60 days. The results showed as follows:1)the final body weight（FBW）,average daily feed intake（ADFI）and average daily gain（ADG）of meat rabbits were significantly affected by different dietary levels of Cinnamomum longepaniculatum leaves（P ＜0.05）. The highest FBW and ADG were found in 3% Cinnamomum longepaniculatum leaf supplemental group,and the lowest FBW,ADFI and ADG were found in 12% Cinnamomum longepaniculatum leaf supplemental group,which were significantly lower than those in the control group（P＜0.05）. 2)Different dietary levels of Cinnamomum longepaniculatum leaves had significant effects on the pre-slaughter body weight,half carcass weight and all carcass weight of meat rabbits（P＜0.05）,and 3% Cinnamomum longepaniculatum leaf supplemental group had the highest values of the above three indexes. The pre-slaughter body weight and half carcass weight in 12% Cinnamomum longepaniculatum leaf supplemental group were significantly lower than those in the other groups（P＜0.05）,and the all carcass weight was significantly lower than that in 3% and 6%Cinnamomum longepaniculatum leaf supplemental groups（P＜0.05）. 3)Different dietary levels of Cinnamomum longepaniculatum leaves had significant effects on the cooking loss,shear force and crude protein（CP）content in muscle of meat rabbits（P＜0.05）. The muscle cooking loss in 6% Cinnamomum longepaniculatum leaf supplemental group was significantly lower than that in other groups（P＜0.05）;the muscle shear force in3% Cinnamomum longepaniculatum leaf supplemental group was the lowest,and significantly lower than that in 6% and 12% Cinnamomum longepaniculatum leaf supplemental groups（P＜0.05）;the CP content in muscle in 3% Cinnamomum longepaniculatum leaf supplemental group was significantly lower than that in 6% and12% Cinnamomum longepaniculatum leaf supplemental groups（P＜0.05）. 4)The organ indices were not significantly affected by different dietary levels of Cinnamomum longepaniculatum leaves（P＞0.05）. 5)Different dietary levels of Cinnamomum longepaniculatum leaves had significant effects on the contents of serum globulin（GLB）,triglyceride（TG）and phosphorus（P ＜ 0. 05）,and the serum GLB content in 3% Cinnamomum longepaniculatum leaf supplemental group was significantly higher than that in the other groups（P ＜ 0.05）.Compared with the control group,there was no significant difference in serum TG content in 3% and 6% Cinnamomum longepaniculatum leaf supplemental groups（P＞0.05）,but the serum TG content in 12% Cinnamomum longepaniculatum leaf supplemental group was significantly increased（P＜0.05）. The serum phosphorus content in 3% Cinnamomum longepaniculatum leaf supplemental group was significantly higher than that in the control group（P＜0.05）. In conclusion,the appropriate dietary level of Cinnamomum longepaniculatum leaves has no obvious adverse effects on growth performance,slaughter performance,muscle quality,organ indices and serum biochemical indices of meat rabbits,and the appropriate supplemental level is 3%.[Chinese Journal of Animal Nutrition,2023,35（4）:2533-2545]
This study aimed to investigate the effects of plant miR156a-5p on intestinal microbiota and epithelial barrier of Wuzhishan weaned piglets. Twelve 35-day-old Wuzhishan weaned piglets with initial body weight of（5.82±0.13）kg were randomly divided into 2 groups with 6 replicates per group and one piglet per replicate. Piglets in the control group were fed nonsense single-stranded nucleic acids,and others in experimental group were fed synthetic plant miR156a-5p（600 pmol/kg per day）.The experiment lasted for 7 days. The results showed that compared with the control group,1)the final body weight and average daily gain of experimental group were no significant difference（P＞0.05）,and the lung index was significantly increased（P＜0.05）;2)the serum albumin and high-density lipoprotein cholesterol contents of experimental group were significantly increased（P＜0.05 or P＜0.01）;3)the duodenal Chao1 index and Observed＿otus index of experimental group were significantly increased（P＜0.05）,the jejunal Simpson index was significantly decreased（P＜0.05）,the cecal Shanon index and Simpson index were significantly increased（P＜0.05 or P＜0.01）,and the colonic Simpson index was significantly increased（P＜0.05）;4)the enrichment of Bacteroidales,Bacteroidia,and Bacteroides in duodenum of experimental group were significantly increased（P＜0.05）,and the enrichment of Leptotrichia,Oscillibacter,UCG-010,Helicobacter,Desulfovibrio,Clostridia ＿ vadinBB60 ＿group,Parasutterella and Rikenella in duodenum were significantly increased（P ＜ 0. 05）;5)the duodenal crypt depth and pH of experimental group were significantly increased（P＜0.01）;6)the mRNA relative expression levels of apolipoprotein A1（APOA1）and tail-type homology cassette transcription factor 2（CDX2）in duodenum of experimental group were significantly increased（P＜0.01）,and the mRNA relative expression levels of mucin 2（MUC2）,tumor necrosis factor-α（TNF-α）andβdefensin 1（DEFB1）in duodenum were significantly increased（P＜0.05）. In conclusion,plant miR156a-5p can regulate theαvariety of microbiota in duodenum,jejunum,caecum and colon of Wuzhishan weaned piglets,it can also increase the pH and the enrichment of Bacteroidales,Bacteroidia and Bacteroides in duodenum,as well as duodenal epithelial differentiation,chemical and mucosal immune barrier functions.[Chinese Journal of Animal Nutrition,2023,35（4）:2184-2195]
本试验旨在探究不同化学处理对花棒营养价值及体外瘤胃发酵特性的影响.采用单因素试验设计,设置为对照组(花棒中不添加任何物质)、氨化组(添加花棒干物质重量4％的尿素)、碱化组(添加花棒干物质重量6％的氢氧化钙),每组6个重复,室温下贮存30 d后测定相关指标.结果显示:1)电镜图显示,对照组花棒呈现出了完整的纤维结构,细胞壁纤维结构基本没有被破坏,氨化组和碱化组花棒细胞壁纤维结构己经被破坏;花棒细胞壁纤维结构破坏程度为碱化组＞氨化组＞对照组.在干物质含量方面,氨化组显著低于对照组(P＜0.05),碱化组显著高于对照组(P＜0.05);在粗蛋白质含量方面,氨化组显著高于对照组和碱化组(P＜0.05);在中性洗涤纤维含量方面,氨化组和碱化组均显著低于对照组(P＜0.05);在酸性洗涤纤维含量方面,碱化组显著低于氨化组和对照组(P＜0.05);在半纤维素、纤维素含量方面,碱化组显著低于对照组和氨化组(P＜0.05);在钙和粗灰分含量方面,碱化组显著高于对照组和氨化组(P＜0.05).2)在单宁含量方面,氨化组和碱化组显著低于对照组(P＜0.05),且碱化组显著低于氨化组(P＜0.05);在原花青素、总酚含量方面,氨化组和碱化组显著低于对照组(P＜0.05).此外,氨化组和碱化组还原糖产量均较对照组显著提高(P＜0.05).3)体外培养3、6、9、12 h时,产气量3组间差异不显著(P＞0.05);体外培养24、36、48、72 h时,碱化组产气量显著高于对照组和氨化组(P＜0.05).体外培养72 h时,碱化组和氨化组发酵液pH与对照组相比均无显著变化(P＞0.05);与对照组相比,碱化组发酵液中氨态氮(NH3-N)浓度无显著变化(P＞0.05),氨化组则显著升高(P＜0.05);氨化组和碱化组发酵液中微生物蛋白(MCP)浓度均较对照组显著提高(P＜0.05);碱化组发酵液中总挥发性脂肪酸(TVFA)浓度显著高于对照组和氨化组(P＜0.05).综上所述,氨化和碱化处理均可以提高花棒的营养价值,降低酚类物质含量,改善体外瘤胃发酵状态,其中碱化处理效果优于氨化处理.
本试验旨在探究褐藻寡糖(AOS)对呕吐毒素(DON)诱导小鼠肝脏损伤的影响.选取32只7周龄雌性C57BL/6J小鼠,适应1周后,随机分为4个组:基础饲粮组(CON组)、褐藻寡糖组(AOS组)、呕吐毒素组(DON组)、褐藻寡糖+呕吐毒素组(AOS+DON组),每组8只小鼠.试验共28 d,分为DON处理前和处理后;前21 d,AOS组和AOS+DON组小鼠每天灌胃200 µL(200 mg/kg BW)AOS,CON组和DON组小鼠每天灌胃等体积无菌生理盐水;后7 d,DON组和AOS+DON组小鼠每天灌胃100 μL(4.8 mg/kg BW)DON,CON和DON组小鼠每天灌胃等体积无菌生理盐水.结果表明:1)与CON组相比,AOS组的10和11周龄体重显著增加(P＜0.05).与CON组相比,DON组的12周龄体重显著降低(P＜0.05),肝脏指数显著增加(P＜0.05);与DON组相比,AOS+DON组的12周龄体重显著增加(P＜0.05),肝脏指数显著降低(P＜0.05).2)与CON组相比,DON组的血清和肝脏白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)含量显著增加(P＜0.05),血清白细胞介素-8(IL-8)含量显著增加(P＜0.05);与DON组相比,AOS+DON组的血清和肝脏IL-1β、IL-6和TNF-α含量显著降低(P＜0.05),血清IL-8含量显著降低(P＜0.05).3)与CON组相比,DON组的肝脏丙二醛(MDA)含量显著增加(P＜0.05),肝脏总超氧化物歧化酶(T-SOD)活性显著降低(P＜0.05);与DON组相比,AOS+DON组的肝脏MDA含量显著降低(P＜0.05),肝脏T-SOD活性显著增加(P＜0.05).4)肝脏组织病理学分析结果表明,DON组肝细胞出现明显的点状坏死,且变形、肿胀,存在炎症浸润、脂质沉积,有特征性放射纤维状,添加AOS可明显改善上述病理损伤症状.F4/80免疫荧光染色结果表明,与CON组相比,DON组的肝脏巨噬细胞含量显著增加(P＜0.05);与DON组相比,AOS+DON组的肝脏巨噬细胞含量显著降低(P＜0.05).5)与CON组相比,DON组的血清谷草转氨酶(AST)、谷丙转氨酶(ALT)、乳酸脱氢酶(LDH)活性和甘油三酯(TG)、总胆固醇(TC)含量均显著增加(P＜0.05);与DON组相比,AOS+DON组的血清AST、ALT、LDH活性和TG、TC含量均显著降低(P＜0.05).综上所述,AOS可改善肝脏指数和病理组织结构,降低血清和肝脏中炎症细胞因子的含量,进而缓解DON诱导的小鼠肝脏损伤.
本研究旨在探究琼胶寡糖缓解呕吐毒素(DON)诱导小鼠肝脏损伤的作用效果与机制.选取32只7周龄、初始体重为(20.04±0.80)g的无特定病原体(SPF)级C57BL/6J雌性小鼠,随机分为4个组,每组8个重复,每个重复1只小鼠.对照组(CON组)和呕吐毒素组(DON组)小鼠每天灌胃200 μL无菌生理盐水,琼胶寡糖组(AO组)和琼胶寡糖+呕吐毒素组(AO+DON组)小鼠每天灌胃200 μL(200 mg/kg BW)琼胶寡糖,连续处理21 d;随后,DON组和AO+DON组小鼠每天灌胃100 μL(4.8 mg/kg BW)DON,CON组和AO组小鼠每天灌胃100 μL无菌生理盐水,连续处理7 d.试验期28 d.结果表明:1)与CON组和AO组相比,DON组和AO+DON组小鼠肝脏指数显著增加(P＜0.05).2)与CON组相比,DON组血清和肝脏白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)含量显著增加(P＜0.05),肝脏白细胞介素-6(IL-6)和丙二醛(MDA)含量显著增加(P＜0.05),总抗氧化能力(T-AOC)及过氧化氢酶(CAT)、总超氧化物岐化酶(T-SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性显著减少(P＜0.05).与DON组相比,AO+DON组血清和肝脏IL-1β和TNF-α含量显著减少(P＜0.05),肝脏IL-6和MDA含量显著减少(P＜0.05),T-AOC及CAT、T-SOD和GSH-Px活性显著增加(P＜0.05).3)肝脏组织病理结果表明DON组肝细胞出明显的炎性浸润,排列呈现不规则结节撞,有特征性放射纤维状,然而AO+DON组肝脏呈现明显改善.F4/80免疫荧光染色结果表明与CON组相比,DON组肝脏巨噬细胞浸润显著增加(P＜0.05);与DON组相比,AO+DON组肝脏巨噬细胞浸润显著降低(P＜0.05).4)与CON组相比,AO组肝脏谷丙转氨酶(ALT)、谷草转氨酶(AST)活性和总胆固醇(TC)、甘油三酯(TG)含量显著降低(P＜0.05),而DON组肝脏AST、ALT活性和TG、TC含量显著增加(P＜0.05).与DON组相比,AO+DON组肝脏AST、ALT活性和TC含量显著降低(P＜0.05).5)与CON组相比,DON组肝脏IL-1β、TNF-α、IL-6、核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)、半胱天冬蛋白酶-3(Caspase-3)、微管相关蛋白1轻链3β(LC3B)的mRNA相对表达水平显著升高(P＜0.05).与DON组相比,AO+DON组肝脏IL-1β、TNF-α、IL-6、NLRP3、Caspase-3、LC3B 的 mRNA 相对表达水平显著降低(P＜0.05).综上所述,琼胶寡糖能够通过改善小鼠肝脏抗炎、抗氧化功能,调节免疫细胞因子分泌,抑制肝脏组织病理学损伤和炎性浸润,缓解DON诱导的小鼠肝脏损伤.
本试验旨在研究交换和组合附生微生物对青绿饲料青贮品质和有氧稳定性的影响.以甘蔗尾叶和象草为研究对象,通过高速离心(15 000×g,90 min)浸提液的方法得到其附生微生物,通过高温干燥灭菌(65 ℃,3 h;105 ℃,15 h)的方法得到灭菌原料.将灭菌后的甘蔗尾叶(S)和象草(E)分别接种甘蔗尾叶附生微生物(MS)、象草附生微生物(ME)以及两者混合附生微生物(1∶1)(MES)进行青贮.试验共6个处理,分别为E×ME、E×MS、E×MES、S×ME、S×Ms和S×MES,每个处理5个重复,青贮100 d.青贮后进行12 d的有氧稳定性测定,对青贮开封时样本及青贮有氧不稳定时样本进行发酵指标测定.结果表明:青贮原料对青贮的干物质(DM)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)、粗蛋白质(CP)和粗灰分(Ash)含量有显著影响(P＜0.05),附生微生物对青贮的DM、粗纤维(CF)和Ash含量有显著影响(P＜0.05).青贮原料与附生微生物的交互作用对青贮的DM、NDF、CP、CF和Ash含量有显著影响(P＜0.05).青贮原料和附生微生物及其交互作用均对青贮的pH及乳酸、氨态氮、乙醇、乙酸、丙酸和丁酸含量有显著影响(P＜0.05).青贮原料和附生微生物及其交互作用均对乳酸菌、酵母菌和霉菌数量有显著影响(P＜0.05).综上所述,甘蔗尾叶附生微生物以及甘蔗尾叶和象草混合附生微生物会提高象草青贮的有氧稳定性,甘蔗尾叶和象草混合附生微生物的发酵会提高甘蔗尾叶青贮品质.
本研究旨在对兰坪乌骨绵羊和普通绵羊在血浆代谢组学方面进行差异性比较.试验采用液相色谱串联质谱(LC-MS/MS)技术研究了 12只兰坪乌骨绵羊和12只兰坪本地普通绵羊在血浆代谢组中不同代谢物特征.结果表明,共获得181种差异代谢物(P＜0.05),其中阿苯达唑亚砜、阿苯达唑砜、4-羟基异亮氨酸等48种代谢物表达上调,麦考酚酸、异丙肾上腺素、18-羟基二十碳五烯酸等133种代谢物表达下调.代谢途径分析显示,差异代谢物富集于胆汁分泌、药物代谢-细胞色素P450、醛固酮调节的钠重吸收等9条通路,且在其中发现了 6种标志代谢物(去氧胆酸、胆酸、石胆酸、鹅去氧胆酸、氢化可的松、雌三醇)参与调节兰坪乌骨绵羊的免疫、营养物质代谢、抗氧化能力等生物过程.通过研究结果显示出兰坪乌骨绵羊和普通绵羊血浆代谢组学上的差异,为深入了解兰坪乌骨绵羊和普通绵羊生长及抗逆性能的潜在代谢机制提供了理论依据.
本试验旨在研究饲粮中添加不同剂型丁酸对肉鸡生长性能、肠道健康的影响.试验1(饲养试验):选取1日龄罗斯308商品肉仔鸡公母鉴别雏2 100只,分为5组,每组12个重复(公母分饲,各6个重复),每个重复35只.1组为空白对照组(NC组),饲喂基础饲粮,不含维吉尼亚霉素和丁酸;2组为抗生素组(PC组),饲喂基础饲粮+10 mg/kg维吉尼亚霉素;3组为丁酸钠(SB)组,饲喂基础饲粮+0.5 g/kg SB;4组为三丁酸甘油酯(TB)组,饲喂基础饲粮+0.5 g/kg TB;5组为单丁酸甘油酯(MB)组,饲喂基础饲粮+1.0 g/kg MB.各组试验鸡自由采食、饮水,试验期39 d.试验2(丁酸体内代谢研究):试验动物和分组同试验1,1～2组处理同试验1,3～5组在NC组的基础上添加不同剂型丁酸(SB、TB、MB),使饲粮中丁酸根离子的浓度均达到1.0 g/kg.28日龄开始,预试期5 d,正试期3 d.取十二指肠、空肠和回肠食糜,测定挥发性脂肪酸(VFA)含量和pH.结果表明:1)1～10日龄,维吉尼亚霉素和不同剂型丁酸对肉仔鸡料重比(F/G)、平均日采食量(ADFI)和成活率的影响均不显著(P＞0.05);TB组体重(BW)和平均日增重(ADG)显著低于NC和SB组(P＜0.05).11～24日龄,抗生素和各丁酸组对肉鸡F/G、ADG和成活率的影响均不显著(P＞0.05);NC组BW和ADFI显著高于PC、TB、MB组(P＜0.05).25～39日龄和全阶段,PC和TB组F/G显著低于NC组(P＜0.05).全阶段,SB、TB和MB能提高肉鸡成活率,分别提高1.86％、1.86％和4.49％.2)与NC组相比,使用抗生素和丁酸处理对全净膛率、胸肌率、腿比率、腹脂率、免疫器官相对重量、步态和脚垫评分的影响均不显著(P＞0.05),丁酸能在一定程度上提高全净膛率(P=0.099).3)与NC组相比,MB组回肠相对重量显著提高(P＜0.05);PC、MB组回肠单位长度重显著提高(P＜0.05);丁酸能在一定程度提高空肠单位长度重(P=0.052).4)饲粮中使用丁酸可提高十二指肠中丁酸含量;TB组十二指肠和空肠中丁酸含量显著提高(P＜0.05);不同剂型丁酸组肉鸡肠道中丁酸含量从十二指肠到回肠呈降低趋势.饲粮中使用丁酸对各肠道丙酸含量、pH没有显著影响(P＞0.05).综上所述,肉鸡饲粮中使用丁酸,有利于提高肉鸡增重和降低F/G,并对肉鸡肠道发育有益,丁酸经过甘油酯化效果好于SB,其中TB效果更佳.
本研究旨在探讨以不同比例油菜秸秆(RAS)和稻草(RIS)替代全株玉米青贮(WCS)对牦牛体外瘤胃发酵特性的影响,筛选出1种适宜组合后,继续研究添加不同种类支链挥发性脂肪酸(BCVFA)对牦牛体外瘤胃发酵特性的影响.试验1设置12个组,每组4个重复,各组底物组成分别为 100％WCS、100％RAS、100％RIS、90％WCS+10％RAS、80％WCS+20％RAS、70％WCS+30％RAS、90％WCS+10％RIS、80％WCS+20％RIS、70％WCS+30％RIS、80％WCS+10％RAS+10％RIS、70％WCS+10％RAS+20％RIS 及 70％WCS+20％RAS+10％RIS,经体外发酵72 h后测定瘤胃发酵参数,确定1种适宜组合.试验2选择1种适宜组合(70％WCS+20％RAS+10％RIS)为底物,添加0.3％BCVFA(干物质基础),设置对照组(不添加BCVFA)及7个试验组,每组4个重复,各试验组分别添加异丁酸(IB)、异戊酸(Ⅳ)、2-甲基丁酸(ME)、IB∶Ⅳ=1:1、IB∶ME=1∶1、Ⅳ∶ME=1∶1及IB∶Ⅳ∶ME=1∶1∶1,经体外发酵72 h后测定瘤胃发酵参数及纤维素酶活性.结果表明:1)与RAS组和RIS组相比,70％WCS+30％RAS组pH显著降低(P＜0.05),微生物蛋白(MCP)和丁酸含量以及干物质降解率(DMD)均显著提高(P＜0.05),且中性洗涤纤维降解率(NDFD)显著高于RAS组(P＜0.05);80％WCS+20％RIS组pH显著降低(P＜0.05),MCP、乙酸、丙酸、丁酸和总挥发性脂肪酸含量以及DMD均显著提高(P＜0.05),且NDFD显著高于 RAS 组(P＜0.05);70％WCS+10％RAS+20％RIS 组 pH 显著降低(P＜0.05),MCP 含量和 DMD 均显著提高(P＜0.05);70％WCS+20％RAS+10％RIS 组 pH 显著降低(P＜0.05),MCP含量和DMD均显著提高(P＜0.05).综合比较,70％WCS+20％RAS+10％RIS组为适宜组合.2)与对照组相比,各试验组MCP含量均显著提高(P＜0.05),其中Ⅳ:ME组最高;挥发性脂肪酸方面,IB:Ⅳ组和IB:ME组丙酸和戊酸含量均显著高于对照组(P＜0.05);养分降解率方面,对照组和IB:Ⅳ:ME组显著高于其余各组(P＜0.05);纤维素酶活性方面,IB:ME组、Ⅳ:ME组及IB:Ⅳ:ME组羧甲基纤维素酶和木聚糖酶活性均显著高于对照组(P＜0.05),其中Ⅳ:ME组最高.综上所述,以 70％WCS+20％RAS+10％RIS 为底物添加 0.3％BCVFA(Ⅳ:IB:ME=1:1:1)能有效改善牦牛体外瘤胃发酵特性.
本试验采用析因法分别研究61～120日龄文昌鸡母鸡的生长净能需要量(NEg)、产蛋净能需要量(NEe)和维持净能需要量(NEm),建立净能需要量(NEr)的预测模型,为文昌鸡的高效养殖提供科学依据.试验1:选择体重[(928.06±3.06)g]接近的63日龄健康文昌鸡母鸡180只,分为1个组,6个重复,每个重复30只鸡.笼养至119 日龄.每周测定文昌鸡的平均体重和体能,建立线性回归模型,计算文昌鸡的NEg;测定文昌鸡母鸡所产鸡蛋的平均净能含量,即为NEe.试验2:分2个阶段(61～90日龄和91～120日龄)研究文昌鸡的NEm,分别选择61和91日龄体重[(824.17±2.82)g和(1 336.67±10.90)g]接近的健康文昌鸡母鸡240只,随机分为4个组(自由采食组及限饲20％、40％和60％组),每组6个重复,每个重复10只鸡.4个组饲喂相同的代谢饲粮.每个阶段试验期30 d,在试验中期测定不同饲喂水平下饲粮的表观代谢能(AME);每个阶段的起始和结束时,测定文昌鸡的沉积能(RE)、代谢能摄入量(MEi)和产热量(HP),建立HP的对数与MEi之间的回归模型,计算文昌鸡的NEm.试验1结果表明:64～91日龄和92～119日龄文昌鸡的NEg分别为19.87和25.05 kJ/g.文昌鸡105 日龄开始产蛋,NEe为6.78 kJ/g.试验2结果表明:在61～90日龄和91～120日龄,40％和60％限饲组的AME显著高于自由采食组(P＜0.05);随着饲喂水平的降低,MEi、RE和HP均显著降低(P＜0.05).MEi与HP之间呈显著的对数回归关系(R2=0.93和0.88,P＜0.05),61～90日龄和91～120日龄文昌鸡的NEm分别为366.44和351.56 kJ/(BW0.75.d).根据计算得出的NEg、NEe和NEm,建立文昌鸡母鸡NEr的预测模型:NEr(kJ/d)=366.44×BW0.75+19.87×ADG(61～90日龄)和NEr(kJ/d)=351.56xBW0.75+25.05xADG+6.78xAEP(91～120 日龄);式中:BW075 为代谢体重,ADG为平均日增重,AEP为平均产蛋量.利用该模型,可以根据体重、ADG和AEP动态预测文昌鸡母鸡的NEr.
仔猪阶段对于整个生猪养殖过程十分关键,然而仔猪肠道免疫系统发育还未完善,肠道微生物区系尚不稳定,易发生疾病.猪饲粮脂肪酸可以调节肠道脂质代谢、增强黏膜屏障和免疫功能以及改善肠道微生物区系组成.本文对仔猪肠道微生物与脂质代谢-免疫应答网络之间的关系进行了综述,并总结了饲粮添加脂肪酸对断奶仔猪肠道免疫反应、微生物区系组成和脂质代谢的影响和作用机制,旨在为应用脂肪酸改善仔猪肠道健康提供参考.
本试验旨在探究蚯蚓液对13～43周龄蛋鸡产蛋性能、蛋品质、血清生化指标和肠道健康的影响.选取432只体重接近的13周龄海兰粉蛋鸡,随机分为4组,每组6个重复,每个重复18只.对照组饲粮中不添加蚯蚓液,1％、2％和3％蚯蚓液组饲粮中分别添加1％、2％和3％的蚯蚓液,试验期30周.结果显示:1)与对照组相比,添加1％蚯蚓液极显著提高了蛋壳厚度(P＜0.01),添加2％蚯蚓液显著提高了蛋壳厚度(P＜0.05);添加1％蚯蚓液显著提高了蛋壳强度(P＜0.05).2)与对照组相比,添加1％、2％或3％蚯蚓液极显著降低了血清肌酐含量(P＜0.01);添加3％蚯蚓液显著降低了血清尿酸含量(P＜0.05).3)与对照组相比,添加1％、2％或3％蚯蚓液增加了盲肠中特有的操作分类单元(OTUs)数量;添加2％蚯蚓液显著提高了蛋鸡肠道微生物的ACE指数、Chao1指数、PD_whole_tree指数(P＜0.05);此外,添加蚯蚓液降低了肠道中脱硫弧菌科、梭杆菌科和甲烷杆菌科等有害菌的相对丰度,提高了理研菌科、Bacteroides caecicola、Megas-phaera stantonii等有益菌的相对丰度.综上所述,蚯蚓液具有提高13～43周龄蛋鸡产蛋性能、蛋品质和降低肾脏损伤的作用,可用于调节肠道菌群,从而保障肠道健康,在蛋鸡养殖业中具有潜在的应用价值.
本研究旨在分析不同月龄岗巴羊肉品质、营养成分及风味前体物质的差异.随机选取自然放牧条件下的6、18和48月龄健康去势岗巴公羊[平均体重分别为(19.67±3.04)kg、(25.08±0.36)kg和(30.68±1.02)kg]作为研究对象,每个月龄岗巴样随机选3只屠宰,测定其背最长肌的pH、色度、剪切力、滴水损失、熟肉率以及常规营养成分、氨基酸、脂肪酸、风味前体物质含量并进行比较分析.结果显示:1)不同月龄岗巴羊肉的屠宰率差异不显著(P＞0.05).6和18月龄岗巴羊肉的滴水损失极显著高于48月龄(P＜0.01),而18月龄岗巴羊肉的剪切力低于其他月龄且熟肉率高于其他月龄,但差异不显著(P＞0.05).2)48月龄岗巴羊肉的蛋白质含量极显著高于6和18月龄(P＜0.05);18和48月龄岗巴羊肉的丝氨酸(Ser)含量显著高于6月龄(P＜0.05),6和18月龄岗巴羊肉的苏氨酸(Thr)含量极显著高于48月龄(P＜0.01),并随月龄升高而增加;6月龄岗巴羊肉的必需氨基酸(EAA)占比显著高于48月龄(P＜0.05);6和18月龄岗巴羊肉的十七碳酸(C17:0)含量显著低于48月龄(P＜0.05).3)6月龄岗巴羊肉的呈鲜物质5'-肌苷酸二钠(IMP)含量显著低于48月龄(P＜0.05).综上所述,不同月龄岗巴羊肉品质、营养成分和风味前体物质含量有较大差异,6月龄岗巴羊肉营养价值较高,18月龄岗巴羊肉品质较好、嫩度高、系水力强,48月龄岗巴羊肉则具有更浓郁的风味.
本试验旨在研究包被植物乳杆菌和低聚果糖对蛋鸡生产性能、蛋品质、免疫能力、粪便臭味及盲肠微生物的影响.选取360只健康的34周龄海兰褐蛋鸡,随机分为4组,每组6个重复,每个重复15只.对照组(CON组)饲喂基础饲粮,试验组分别饲喂在基础饲粮的基础上添加1 g/kg包被植物乳杆菌(MLP组,活菌数为1.0×1010 CFU/g)、1 g/kg低聚果糖(FOS组)以及1 g/kg包被植物乳杆菌+1 g/kg低聚果糖(SYN组)的饲粮.试验期24周.结果表明:1)饲粮中添加包被植物乳杆菌和低聚果糖对蛋鸡生产性能无显著影响(P＞0.05).2)与对照组相比,FOS组和SYN组蛋白高度和哈氏单位显著提高(P＜0.05).3)与对照组相比,MLP组和FOS组蛋鸡血浆干扰素-γ(INF-γ)、白细胞介素-6(IL-6)和白细胞介素-2(IL-2)含量显著降低(P＜0.05),SYN组血浆白细胞介素-10(IL-10)和IL-6含量显著提高(P＜0.05),且SYN组血浆IL-10、IL-6和IL-2含量显著高于MLP组和FOS组(P＜0.05).4)与对照组相比,试验组蛋鸡粪便中吲哚和粪臭素含量均显著降低(P＜0.05).5)在门水平上,与对照组相比,MLP组蛋鸡盲肠厚壁菌门(Firmicutes)和FOS组盲肠拟杆菌门(Bacteroidota)相对丰度提高,试验组盲肠螺旋菌门(Spirochaetota)和脱硫菌门(Desulfobacterota)相对丰度降低.在属水平上,与对照组相比,MLP组盲肠乳杆菌属(Lactobacillus)相对丰度提高,盲肠拟杆菌属(Bacteroides)和理研菌科RC9肠道群(Rikenellaceae_RC9_gut_group)相对丰度降低;FOS组盲肠拟杆菌属和罗姆布茨菌属(Romboutsia)相对丰度提高;SYN组盲肠瘤胃球菌属扭链群(Ruminococcus_torques_group)和考拉杆菌属(Phascolarctobacterium)相对丰度有所提高.线性判别分析效应大小(LEfSe)分析表明,对照组蛋鸡盲肠显著富集有害菌脱硫弧菌属(Desulfovibrio)[线性判别分析(LDA)评分＞2,P＜0.05],SYN组盲肠显著冨集有益菌霍氏真杆菌属(Eubacterium_hallii_group)和韦荣氏球菌属(Veillonella)(LDA评分＞2,P＜0.05).综上可知,饲粮中添加包被植物乳杆菌和低聚果糖能够提高蛋鸡蛋品质和免疫能力,改善盲肠微生物组成,降低粪便臭味物质含量;其中,低聚果糖在改善蛋品质和降解臭味物质方面效果较佳,包被植物乳杆菌和低聚果糖联合添加在提高机体免疫能力和改善盲肠微生物组成方面效果较佳.
本试验旨在研究高碳水化合物饲料添加牛磺酸对杂交鳢生长性能、肝脏糖代谢相关基因表达、抗氧化活性及免疫应答的影响.试验选取初始体重为(22.02±0.02)g的杂交鳢450尾,随机分为3组:低碳水化合物组(LC组,碳水化合物含量为21％)、高碳水化合物组(HC组,碳水化合物含量为27％)和高碳水化合物饲料添加牛磺酸组(HT组,碳水化合物含量为27％,牛磺酸添加量为1％),每组3个重复,每个重复50尾鱼,饲喂8周.结果表明:与LC组相比,HC组的血浆葡萄糖(GLU)含量及谷丙转氨酶(ALT)和谷草转氨酶(AST)活性显著增加(P＜0.05);血浆碱性磷酸酶(ALP)活性和肝脏谷胱甘肽过氧化物酶(GSH-Px)活性显著下降(P＜0.05);肝脏白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)、Toll样受体4(TLR4)和髓样分化因子88(MyD88)基因相对表达量显著升高(P＜0.05);肝脏转化生长因子-β(TGF-β)和热休克蛋白70(HSP70)基因相对表达量显著下降(P＜0.05).与HC组相比,HT组的饲料系数(FC),血浆GLU含量及ALT、AST活性,肝脏丙二醛(MDA)和糖原含量显著降低(P＜0.05);蛋白质沉积率(PPV),血浆总蛋白(TP)含量、ALP活性、胰岛素含量,肝脏总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、GSH-Px活性显著增加(P＜0.05);肝脏胰岛素相关基因蛋白激酶B(AKT)和磷脂酰肌醇-3激酶(PI3K)基因相对表达量显著上调(P＜0.05);肝脏糖代谢相关基因丙酮酸激酶(PK)和葡萄糖转运蛋白2(GLUT2)基因相对表达量显著上调(P＜0.05);肝脏白细胞介素-10(IL-10)、TGF-β和HSP70基因相对表达量显著升高(P＜0.05);肝脏白细胞介素-8(IL-8)、IL-1β、TNF-α、TLR4和MyD88基因相对表达量显著下降(P＜0.05).综上所述,高碳水化合物饲料可诱发杂交鳢的氧化应激和炎症,而添加牛磺酸可提高杂交鳢的抗氧化活性,缓解炎症,促进糖代谢.
