Effects of Antimicrobial Peptides and Chinese Herbal Medicine Additives on Growth Performance,Serum Biochemical Indices and Intestinal Morphology of Broilers北大核心CSCD

本试验旨在研究抗菌肽和中草药添加剂对肉鸡生长性能、血清生化指标和肠道形态的影响。选用600只体重相近的10日龄麻黄肉鸡作为试验动物,随机分成4个组,分别为对照组(饲喂基础饲粮)、抗菌肽组(饲喂基础饲粮+200 mg/kg抗菌肽)、中草药组(饲喂基础饲粮+200 mg/kg中草药添加剂)和抗菌肽+中草药组(饲喂基础饲粮+200 mg/kg抗菌肽和200 mg/kg中草药添加剂),每组6个重复,每个重复25只鸡。试验期47 d。结果表明:1)与对照组相比,10~21日龄,抗菌肽组和抗菌肽+中草药组肉鸡10~21日龄平均日采食量显著提高(P<0.05);22~43日龄,抗菌肽组和中草药组肉鸡平均日增重显著提高(P<0.05),试验组平均日采食量和料重比均显著降低(P<0.05),但抗菌肽+中草药组死亡率显著提高(P<0.05);44~56日龄,抗菌肽组和中草药组肉鸡平均日采食量和平均日增重显著提高(P<0.05),料重比显著降低(P <0.05),而抗菌肽+中草药组肉鸡平均日采食量显著降低(P<0.05),死亡率显著提高(P<0.05)。2)与对照组相比,抗菌肽组肉鸡血清球蛋白含量显著提高(P<0.05),试验组血清丙二醛和D-乳酸含量显著降低(P<0.05)。3)与对照组相比,抗菌肽组肉鸡十二指肠绒毛高度和绒毛高度/隐窝深度值显著提高(P<0.05),中草药组和抗菌肽+中草药组十二指肠绒毛高度显著提高(P<0.05);抗菌肽+中草药组空肠绒毛高度和绒毛高度/隐窝深度值显著降低(P<0.05),回肠绒毛高度和隐窝深度显著降低(P<0.05),回肠绒毛高度/隐窝深度值显著提高(P<0.05)。综上所述,饲粮添加200 mg/kg抗菌肽或中草药添加剂可以显著提高22~56日龄麻黄肉鸡生长性能,降低血清D-乳酸含量,同时改善小肠形态结构,但两者不宜混合使用。     

Effects of Faba Bean Supplementation on Growth Performance,Intestinal Digestive Enzyme Activities,Intestinal Morphology and Intestinal Flora of Tilapia (Oreochromis niloticus)北大核心CSCD

This study was conducted to investigate the effects of faba bean supplementation on the growth performance, intestinal digestive enzyme activities, intestinal morphology and intestinal flora of tilapia (Oreochromis niloticus). A total of 600 genetic improvement of farmed tilapia with an initial body weight of (500.23± 0.34) g were randomly divided into 4 groups with 3 replicates per group and 50 fish per replicate. Four isonitrogenous and isolipidic experimental diets containing 0 (C0 group, as control), 15% (C15 group), 30% (C30 group) and 60% (C60 group) faba bean were fed to fish during the 100-d feeding trial. Results showed as follows: 1) there were no significant differences in the weight gain rate, specific growth rate, feed coefficient ratio and hepatosomatic index among the groups (P>0.05), the protein efficiency ratio and survival rate in C60 group were significantly higher than those in C0 and C15 groups (P<0.05). 2) There were no significant differences in the activities of amylase, lipase and trypsin among the groups (P>0.05). 3) Compared with the C0 group, the C15, C30 and C60 groups had significantly lower intestinal villus height, villus thickness and muscle thickness (P<0.05). 4) The Simpson index of intestinal flora of tilapia in C15, C30 and C60 groups was lower than that in C0 group, and the difference was significant between C30 and C0 groups (P< 0.05). 5) The intestinal core flora of the four groups of tilapia were mainly Cyanobacteria, Actinobacteriota, Firmicutes, Proteobacteria and Fusobacteriota. Compared with the C0 group, the relative abundance of Proteobacteria in C15, C30 and C60 groups had a significant reduction (P<0.05), and the relative abundances of Fusobacteriota and Cetobacterium in C15 and C60 groups had a significant reduction (P<0.05). To conclude, under the conditions of isonitrogenous and isolipidic, diets supplemented with 15% to 60% faba bean have no significant effects on the growth performance and intestinal digestive enzyme activities of tilapia, but can significantly reduce the intestinal villi height, villus width and muscle thickness, decrease the relative abundance of Proteobacteria and the diversity of intestinal flora. © 2023 Authors. All rights reserved.     

Effects of Bile Acid on Growth Performance,Slaughter Performance and Lipid Metabolism of White Feather Broilers北大核心CSCD

本试验旨在研究饲粮添加胆汁酸对白羽肉鸡生长性能、屠宰性能和脂类代谢的影响。选取体况一致和体重接近的1日龄爱拔益加(AA)肉仔鸡240只,随机分为2个组,每组6个重复,每个重复20只鸡。对照组饲喂基础饲粮,试验组在基础饲粮中添加300 mg/kg胆汁酸。试验期42 d。结果表明:1)与对照组相比,试验组白羽肉鸡1~42日龄料重比显著降低(P<0.05)。2)与对照组相比,试验组白羽肉鸡屠宰率显著提高(P<0.05),腹脂率有降低趋势(P=0.071)。3)与对照组相比,试验组白羽肉鸡肝脏脂肪含量有降低趋势(P=0.054),血清谷草转氨酶活性显著降低(P<0.05),血清甘油三酯含量有降低趋势(P=0.090)。综上所述,在本试验条件下,饲粮添加300 mg/kg胆汁酸可以降低白羽肉鸡料重比,提高屠宰率,对脂类代谢有一定的改善作用。     

Effect of Ampelopsis grossedentata Extract on Growth Performance，Diarrhea Rate and Anti-oxidation Function in Mice

The effects of Ampelopsis grossedentata extract on growth performance, diarrhea rate and anti-oxidation function in mice were studied in this experiment. 90 mice were randomly divided into five groups: Blank group, experimental groups Ⅰ,Ⅱ,Ⅲ and control group. The mice in blank group were fed with basal diet, the experimental groups were added with 0.02, 0.04, 0.06 mg/(g·BW) of Ampelopsis grossedentata extract and the control group was added with colistin sulfate in basal diets, respectively. On the 26th day of the trial, the mice were administered folium senna and then record their diarrhea condition. The results showed that, the finial weights of mice in experimental and control groups were higher than that in blank group, and the difference between the blank and control groups were significant (P<0.05). Adding Ampelopsis grossedentata extract had a tendency to increase growth performance and liver weight, but the difference was not significant (P>0.05). The diarrhea rates in the control and experimental groups Ⅱ,Ⅲ were significantly lower than the blank and experimental group Ⅰ(P<0.05). Compared with the blank group, the activity of the serum glutathione peroxidase (GSH-Px) was significantly increased in control group (P<0.05), while the increasing trends were not significant in experimental groups (P>0.05). The activity of catalase (CAT) in control group was significantly higher than that in experimental group Ⅱ (P<0.05), and the serum superoxide dismutase (SOD) activities among the experimental groups were not significant (P>0.05). In conclusions, the growth performance and anti-oxidation function in mice could be increased, while the diarrhea rate could be decreased by adding the Ampelopsis grossedentata extract. It suggested that Ampelopsis grossedentata extract was expected to become a substitute for antibiotics in animal feeds.     

Effects of Dietary Broussonetia papyrifera Leaves on Growth Performance,Serum Biochemical Indexes,Intestinal Morphology and Cecal Microflora of Guangxi Sanhuang Chickens北大核心CSCD

本试验旨在研究饲粮中添加杂交构树叶对广西三黄鸡的生长性能、血清生化指标、免疫器官指数、肠道组织形态及盲肠菌群的影响。选取120只健康的1日龄广西三黄鸡,随机分为4组,每组3个重复,每个重复10只。A组为对照组,饲喂不添加杂交构树叶的基础饲粮;B、C、D组分别在基础饲粮中添加3%、6%、9%的杂交构树叶,试验期为21 d。结果显示:与对照组相比,饲粮中添加3%~6%的杂交构树叶对生长性能、血清生化指标以及肠道组织形态均无显著影响(P>0.05);饲粮中添加6%的杂交构树叶可显著提高法氏囊指数(P<0.05);饲粮中添加9%的杂交构树叶可显著提高血清中丙氨酸氨基转移酶(ALT)活性(P<0.05),显著降低平均日增重和脾脏指数(P<0.05),显著增加料重比(P<0.05)。肠道菌群分析显示,与对照组相比,饲粮添加6%的杂交构树叶对盲肠菌群的Alpha多样性指数无显著影响(P>0.05);在属水平上,饲粮添加6%的杂交构树叶可显著降低欧氏菌属(Olsenella)、理研菌科RC9肠道群(Rikenellaceae_RC9_gut_group)、norank_f_norank_o_Gastranaerophilales、norank_f_norank_o_RF39、脱硫弧菌属(Desulfovibrio)、norank_f_norank_o_Rhodospirillales的比例(P<0.05),同时显著增加另枝菌属(Alistipes)、乳杆菌属(Lactobacillus)、Sellimonas、Negativibacillus、厌氧棒状菌属(Anaerostipes)的比例(P<0.05)。综上所述,本试验条件下,饲粮中添加3%~6%的杂交构树叶对广西三黄鸡的生长性能、血清生化指标、免疫性能、肠道组织形态均无负面影响,且添加6%的杂交构树叶还可以提高广西三黄鸡的法氏囊指数,改善盲肠菌群结构。     

Effects of Soybean Meal Replaced by Fermented Plant Protein Compound on Growth,Immune, Antioxidant and Intestinal Microflora Structure of Black Carp (Mylopharyngodon piceus)北大核心CSCD

This experiment was conducted to study the effects of soybean meal replaced by fermented plant protein compound on growth, immune, antioxidant and intestinal microflora structure of black carp (Mylopharyn-godon piceus). The different proportions (1∶1 and 2∶1) of fermented cottonseed meal and fermented rapeseed meal were used to replace 0 (control group), 50% and 75% soybean meal in the basic diet, respectively, 5 kinds of isonitrogenous and isoenergetic experimental diets were prepared, and the black carp with initial weight of (6. 04 ± 0. 18) g were fed for 8 weeks. The results showed that there were no significant differences on growth performance, morphological indicators and body composition among all group (P>0.05). There were no significant differences on serum complement 3, malondialdehyde, albumin contents and lysozyme activity among all group (P>0.05). The serum complement 4 content in 50% replacement group was significantly higher than that in other groups (P<0.05), and the serum immunoglobulin M content in 75% replacement group was significantly higher than that in the control group (P<0.05). There were no significant differences on hepatopancreas superoxide dismutase, catalase, alkaline phosphatase activities and total antioxidant capacity and total cholesterol content among all group (P>0.05). There were no significant differences on intestinal α-amylase and lipase activities among all group (P>0.05), and the intestinal pepsin activity in fermented cottonseed meal and fermented rapeseed meal replacing 75% soybean meal with 1 ∶ 1 proportion group was significantly higher than that in the control group (P<0.05). The dominant microflora in intestine of black carp at the phylum level were Proteobacteria, Firmicutes, Fusobacteria and Planctomycotes, and the dominant bacteria at the genus level were Aeromonas, Cetobacterium, Ralstonia and Plesiomonas. There were no significant differences on the relative abundances of intestinal main microflora among all group (P>0.05). To sum up, under the experimental conditions, the high proportion (75%) of fermented plant protein replacing soybean meal do not cause hepatopancreas damage and intestinal microflora structure change of black carp, and even improve the activities of some immune indicators in serum and intestinal protease activity, and the compound proportion of fermented cottonseed meal and fermented rapeseed meal have no significant effects on growth performance, morphological indicators, body composition, hepatopancreas antioxidant indexes and intestinal microflora structure of black carp. © 2023 Chinese Journal of Urology. All rights reserved.     

Effects of Wheat and Fermented Sesame Meal on Growth Performance，Meat Quality and Serum Biochemical Indexes in Broilers

This study was to investigate the effects of different proportions of wheat and fermented sesame meal on growth performance,meat quality and serum biochemical indexes in broilers under the condition of adding exogenous enzymes in the diet.A total of 520 21-day-old broilers （fast）with an average body weight of （330±10）g were randomly assigned to 5 groups with 4 replicates in each group and each replicate contained 26 broilers. Broilers in the 5 groups were fed experimental diets containing 0 (control group),20% wheat +5% fermented sesame meal （group Ⅰ）,40% wheat +10% fermented sesame meal （group Ⅱ）,20% wheat + soybean meal （group Ⅲ） and 40% wheat + soybean meal （group Ⅳ）,respectively.The pre-test period lasted for 3 days and the trial period lasted for 34 days.The results showed that compared with the control group,the ADG in groups Ⅰ,Ⅱ,Ⅲ and Ⅳ was significantly decreased by 9.40%,7.15%,8.87%,5.46% （P＜0.05）,respectively,while the ADFI and F/G showed no significant differences （P＞0.05）.There were no significant differences on meat quality among all experimental groups（P＞0.05）, respectively, but group Ⅱ had better meat quality than others.Compared with the control group,the content of alanine aminotransferase in serum in groups Ⅲ, Ⅳ was significantly decreased by 30.10%,25.36% （P＜0.05）,but there were no significant differences in the contents of total protein,urea nitrogen and aspartate aminotransferase in serum in all experimental groups（P＞0.05）.In conclusion,under the experimental conditions,adding appropriate proportions of wheat and sesame meal could replace part of the corn and soybean meal in the diet,and the better supplementation level of wheat and fermented sesame meal was 40% and 10%,respectively.     

Effects of Antibacterial Peptide Cecropin on Prouduction Performance，Immune Function and Serum Biological Parameters of Weaner Piglets

This experiment was conducted to study the effects of antimicrobial peptide cecropin on production performance,immune function and serum biological parameters of weaner piglets.A total of 240 weaner hybrid piglets （Landrace×Large White×Duroc） with average body weight （8.35±0.12）kg were randomly divided into 4 treatments with 6 replicates of 10 each.The four treatments were control group （fed a basal diet）,antibiotics group （fed basal diet＋140 mg/kg 50% kitasamycin＋100 mg/kg olaquindox ＋600 mg/kg 10% colistin sulfate）,antimicrobial peptide group （fed basal diet＋350 mg/kg antimicrobial peptide cecropin）,compatibility group （antibiotics + antibacterial peptide group）（fed basal diet＋250 mg/kg antimicrobial peptide cecropin＋50 mg/kg olaquindox ＋200 mg/kg 10% colistin sulfate）,each group was half male and half female.The pre-test period lasted for 7 days,the trial period lasted for 34 days.The results showed that compared with control group,the average daily gain in compatibility group was significantly increased （P＜0.05）,the average daily feed intake in antibiotic group and antimicrobial peptide group was significantly decreased （P＜0.05）,the feed conversion ratio and diarrhea rate in all three experimental groups were significantly decreased （P＜0.05）.The antibody blocking rate and serum IgG,IgA contents in antimicrobial peptide group and compatibility group were significantly increased （P＜0.05）,the serum urea nitrogen and blood sugar contents in antimicrobial peptide group and compatibility group were significantly decreased （P＜0.05）,but the serum total protein and albumin contents were significantly increased （P＜0.05）.In conclusion,dietary supplementation appropriate level of antimicrobial peptide cecropin could replace part of the antibiotics,and adding high dose of antimicrobial peptide cecropin could replace antibiotics used in feed completely.     

Effects of Dietary Coated Sodium Butyrate on Growth Performance,Antioxidant Capacity and Inflammatory Response of Broilers under Cyclically Heat-Stress Condition北大核心CSCD

This experiment investigated the effects of dietary coated sodium butyrate (CSB) on the growth performance, antioxidant capacity and inflammatory response of broilers under cyclically heat-stress condition. The experiment selected 500 one-day-old Arbor Acres (AA) broilers, and when routine immunization and rearing to 21-day-old, four hundred and fifty healthy and similar body weight broilers were selected and randomly divided into 5 groups with 6 replicates per group and 15 chickens per replicate. Five groups were divided into one normal temperature group (NT group), one heat stress group (HS group) and three heat stress and adding CSB groups (HS+CSB groups) . Broilers in the NT group were raised in room temperature environment [(24± 2) °C], and fed a basal diet. Broilers in the HS group and HS+CSB groups were raised in a daily high temperature environment (28 °C -36 °C -28 °C), and fed diets supplemented with 0, 300, 600 and 900 mg / kg CSB in the basal diet, respectively. The experiment lasted for 14 d. The results showed as follows: 1) compared with the NT group, cyclically heat-stress extremely significantly reduced the average daily feed intake and average daily gain of broilers (P < 0. 01) . Under the cyclically heat-stress condition, the addition of 900 mg / kg CSB significantly increased the average daily gain and average daily feed intake of broilers (P < 0.05), and the addition of 600 mg / kg CSB significantly increased the average daily gain of broilers compared with HS group (P<0.05) . 2) Compared with the NT group, cyclically heat-stress significantly or extremely significantly decreased serum glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) activities and total antioxidant capacity (T-AOC) of broilers (P<0.05 or P<0.01), and significantly or extremely significantly increased serum lactic dehydrogenase (LDH) and creatine kinase (CK) activities and the content of malondialdehyde (MDA), α1-acidoglycoprotein (α1-AGP), endotoxin (ET) and thiobarbituric acid reactive substance (TBARS) (P < 0. 05 or P < 0. 01) . Under the cyclically heat-stress condition, compared with the NT group, the addition of 900 mg / kg CSB significantly increased the serum GSH-Px, CAT and SOD activities and T-AOC (P < 0. 05), and significantly or extremely significantly decreased the serum LDH activity and α1-AGP, ET and TBARS contents of broilers (P < 0. 05 or P < 0. 01); the addition of 600 mg / kg CSB significantly increased the serum CAT and SOD activities (P<0.05), and extremely significantly decreased the serum LDH activity of broilers (P<0.01); the addition of 300 mg / kg CSB significantly increased the serum CAT and SOD activities and T-AOC of broilers (P < 0. 05) . 3) Compared with the NT group, cyclically heat-stress extremely significantly increased the serum contents of pro-inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-8 (IL-8) of broilers (P<0.01) . Under the cyclically heat-stress condition, compared with the NT group, the addition of 900 mg / kg CSB significantly or extremely significantly reduced the serum IL-6, TNF-α, IL-1β and IL-8 contents of broilers (P < 0. 05 or P < 0. 01), and significantly increased serum transforming growth factor-β (TGF-β) content (P<0.05); the addition of 600 mg / kg CSB significantly or extremely significantly reduced the serum IL-6 and TNF-α contents of broilers (P<0.05 or P<0.01); the addition of 300 mg / kg CSB significantly reduced the serum TNF-α content of broilers (P<0.05) . Above results indicate that the addition of CSB in the diet can improve the growth performance of broilers under the cyclically heat-stress condition by increasing the antioxidant capacity and alleviating the inflammatory response, and adding 900 mg / kg CSB to the diet in this experiment has the best effect. © 2023 Chinese Journal of Animal Science and Veterinary Medicine Co., Ltd. All rights reserved.     

黄芪多糖对肉鸡生长性能和免疫功能的影响

为在肉鸡养殖生产中推广应用黄芪多糖,研究探讨了黄芪多糖对肉鸡生长性能和免疫功能的影响,结果显示,黄芪多糖添加组与对照组相比,可显著增加日均增重量、胸腺指数、脾脏指数、法氏囊指数(P<0.05),显著降低料重比(P<0.05)。表明肉鸡日粮中添加0.1%黄芪多糖能显著提高肉鸡的生长性能和免疫功能。     

Effects of Dietary Tributyrin on Growth Performance,Serum Biochemical Indices,Immune Function and Antioxidant Capacity of Juvenile Yellow Catfish (Pelteobagrus fulvidraco)北大核心CSCD

This experiment was conducted to investigate the effects of dietary tributyrin on growth performance, serum biochemical indices, immunity function and antioxidant capacity of juvenile yellow catfish (Pelteobagrus fulvidraco). A total of 480 juvenile yellow catfish with an initial body weight of (5.53±0.02) g were selected and randomly divided into 4 groups with 3 replicates in each group, and 40 fish in each replicate. Four isonitrogenous and isolipid experimental diets were fed with 0 (G0), 500 (G1), 1 000 (G2) and 2 000 mg/kg (G3) triglyceride, respectively. The experiment lasted for 56 days. The results showed as follows: 1) weight gain rate and feed efficiency rate in G2 group were significantly higher than those in other groups (P<0.05). The fatness in G1 group was significantly lower than that in G0 and G3 groups (P<0.05), but there was no significant difference between G1 group and G2 group (P>0.05). 2) The serum glucose content in G3 group was significantly higher than that in G1 and G2 groups (P<0.05), and there were no significant differences in the serum contents of total protein, albumin, globulin, triglyceride, urea nitrogen and the activities of alanine aminotransferase and aspartate aminotransferase among all groups (P>0.05). 3) Compared with G0 group, serum lysozyme activity in G1, G2 and G3 groups was significantly increased (P<0.05), serum alkaline phosphatase activity in G1 and G2 groups was significantly increased (P<0.05), and serum immunoglobulin M content in G2 group was significantly higher than that in G3 group (P<0.05). There was no significant difference in serum complement C3 content among all groups (P>0.05). 4) Compared with G0 group, serum total antioxidant capacity in G1 group was significantly increased (P<0.05), and serum super-oxide dismutase activity in G1, G2 and G3 groups was significantly increased (P<0.05). The serum catalase activity in G3 group was significantly higher than that in G0, G1 and G2 groups (P<0.05), but there were no significant differences in serum glutathione peroxidase activity, glutathione and malondialdehyde contents among all groups (P>0.05). In conclusion, dietary supplementation of 500 to 2 000 mg/kg triglyceride can significantly improve non-specific immune and antioxidant capacity of yellow catfish, and dietary supplementation of 1 000 mg/kg triglyceride can significantly improve weight gain rate and feed efficiency of yellow catfish. Combined with the comprehensive evaluation of growth performance, serum immunity and antioxidant indexes, the optimal supplemental level of triglyceride in yellow catfish diet is 1 000 mg/kg. © 2023 Authors. All rights reserved.     

抗菌肽在肉鸡养殖上的应用

在“全面禁抗”即将来临的背景下,我国肉鸡养殖业面临极大的挑战。抗菌肽不易产生耐药性,作为抗生素的潜在替代品,已成为研究热点。抗菌肽是自然界广泛存在的小分子多肽,具有抵抗外源性病原体感染的活性,是宿主天然免疫系统的重要组成部分。文章就抗菌肽制剂的分类、作用机制,以及抗菌肽在肉鸡养殖中的应用作简要说明,介绍抗菌肽在使用过程中对肉鸡机体生长性能、疾病防治、免疫功能、肠道菌群和肠黏膜结构的影响,并对目前存在问题加以论述。     

黄芪多糖对肉鸡生长性能、免疫功能及屠宰性能的影响

文章旨在研究基础日粮中添加不同水平黄芪多糖对肉鸡生长性能、免疫功能及屠宰性能的影响,试验将200只同养殖场、同批次的1日龄白羽肉鸡随机分为4组,每组5个重复,每个重复10只。其中,对照组肉鸡饲喂玉米-豆粕型常规日粮,其他3组肉鸡分别在常规日粮中添加0.2%（试验1组）、0.4%（试验2组）、0.6%（试验3组）的黄芪多糖,试验为期42d。结果表明,（1）与对照组相比,试验1、2、3组肉鸡21d体重显著提高（P <0.05）,且试验2组肉鸡1～21d平均日增重（ADG）、42d体重、21～42d平均日增重（ADG）、1～42d平均日增重（ADG）显著高于其他3组（P <0.05）。（2）与对照组相比,试验1、2、3组肉鸡血清中免疫球蛋白A(IgA)含量显著提高（P <0.05）,试验2、3组肉鸡血清中免疫球蛋白M(IgM)含量显著高于对照组（P <0.05）;试验1、2、3组肉鸡脾脏指数（SI）显著高于对照组（P <0.05）,试验2、3组肉鸡法氏囊指数（BI）显著高于对照组（P <0.05）。（3）与对照组相比,试验1、2、3组肉鸡屠体重（DW）显著...     

黄芪多糖对三黄肉鸡生长性能及肠道菌群的影响

为研究饲粮中添加不同水平黄芪多糖对三黄肉鸡生长性能及肠道菌群的影响,试验选用健康且体重相近的1日龄三黄肉仔鸡90只,随机分为3组,每组10个重复,每个重复3只。以无任何抗生素添加的玉米-豆粕型饲粮为基础饲粮,各组分别在基础饲粮中添加0（对照组）、0.3％（试验1组）和0.6％（试验2组）的黄芪多糖,试验期56 d。结果表明：（1）饲粮中添加不同水平的黄芪多糖,可显著提高三黄肉鸡生长性能,在28日龄和56日龄时,试验组体重显著高于对照组（P＜0.05）;（2）试验1组盲肠中大肠杆菌和沙门氏菌的数量显著低于对照组（P＜0.05）,乳杆菌和双歧杆菌数量显著高于对照组（P＜0.05）,试验2组盲肠中大肠杆菌和沙门氏菌数量极显著低于对照组（P＜0.01）,乳杆菌和双歧杆菌数量极显著高于对照组（P＜0.01）。由此可见,饲料中添加黄芪多糖可以提高三黄鸡生长性能,优化肠道微生物区系,且黄芪多糖添加量为0.6％效果最明显。     

日粮中添加抗菌肽cecropin AD对AA肉鸡免疫性能及其肠道菌群的影响

试验旨在研究抗菌肽 cecropin AD 对肉鸡免疫功能和肠道菌群的影响。试验选用540只1日龄的健康肉公雏,随机分为5个处理,每个处理6个重复,每个重复18只鸡。日粮处理分别为:①空白对照:基础日粮(玉米-豆粕型);②抗生素组:基础日粮+200mg/kg硫酸粘杆菌素;③低剂量抗菌肽组:基础日粮+150mg/kg抗菌肽;④高剂量抗菌肽组:基础日粮+300mg/kg抗菌肽;⑤协同组:基础日粮+150mg/kg抗菌肽+200mg/kg硫酸粘杆菌素。在试验期内,肉鸡自由采食和饮水。于试验的第21d和第42d测定肉鸡的免疫指标和肠道菌群。试验结果发现,从整个试验期来看,添加抗菌肽组对免疫器官发育均没有显著影响。第21d时,抗菌肽组的血浆IL-6含量显著低于空白组(P<0.05),且添加抗菌肽300mg/kg组含量最低。第21d和第42d时,抗菌肽显著降低了盲肠大肠杆菌和总厌氧菌(P<0.05),但不及抗生素组抑制作用强;而各处理间的乳酸杆菌均没有显著差异。因此本试验制备的抗菌肽 cecropin AD 能很好的抑制有害菌,构成动物免疫屏障。日粮中添加抗菌肽 cecropin AD 能够起到调节肠道菌群,调控免疫反应,提高动物生长性能的作用。     

噬菌体复合制剂对肉鸡生长性能、免疫功能、肠道形态及肠道菌群的影响

本试验旨在研究噬菌体复合制剂对肉鸡生长性能、免疫功能、肠道形态及肠道菌群的影响。选取14 000只体重（850±45） g的37日龄青脚麻鸡,随机分为2组,分别是对照组（基础饲粮）和试验组（基础饲粮+109PFU/mL的噬菌体复合制剂）,每组7个重复,每个重复1 000只,试验期27 d。结果表明：1）与对照组相比,试验组的料重比下降2.81%(P>0.05)。2）与对照组相比,43日龄时,试验组肉鸡胸腺指数和脾脏指数分别增加16.80%(P<0.05)和7.14%(P>0.05);52日龄时,肉鸡法氏囊指数和胸腺指数分别增加8.55%(P>0.05)和7.37%(P>0.05);61日龄时,肉鸡法氏囊指数增加39.66%(P>0.05);43、52及61日龄时,试验组肉鸡血清免疫球蛋白G(IgG)含量分别增加15.85%(P>0.05)、29.54%(P>0.05)和1.45%(P>0.05)。3）与对照组相比,43、52及61日龄时,试验组肉鸡十二指肠、空肠、回肠绒毛高度/隐窝深度显著提高（P<0.05）。4）在门水平上,...     

Effect of Different Ratios of Food to Water of Dry Powder Feed on Growth Performance，Nutrient Digestibility and Nitrogen Metabolism of Growing Wusuli Raccoon Dogs

This experiment was aimed to explore the effect of different ratios of food to water of dry powder feed on growth performance,nutrient digestibility and nitrogen metabolism of growing Wusuli raccoon dogs.Thirty 11-week-old healthy Wusuli raccoon dogs with average body weight of （3.47±0.20） kg were randomly assigned into 3 groups.The Wusuli raccoon dogs were fed experimental diets with dry powder feed of ratio of food to water of 1∶2.5 （group Ⅰ）,1∶3.5（group Ⅱ）,1∶4.5 （group Ⅲ）,respectively.The pre-test period lasted for 7 days and the trial period lasted for 67 days.The results showed that the average daily feed intake of each week from 11,12 to 13 weeks in groupⅠ was significantly less than that in groups Ⅱ and Ⅲ （P＜0.05）,the average daily feed intake of each week from 14,15 to 20 weeks was no significant difference among all groups （P＞0.05）.The total intake in group Ⅰ was significantly less than that in group Ⅱ （P＜0.05）.The average daily gain of each week from 15 to 17 weeks in group Ⅲ was significantly higher than that in group Ⅰ （P＜0.05）,while the average daily gain,total weight and the rate of feed intake to body gain in other week-old were no significant differences among all groups （P＞0.05）.The protein digestibility,fat digestibility and dry matter digestibility were no significant differences among all groups （P＞0.05）.The amount of urine in group Ⅲ was extremely significantly higher than that in groups Ⅰ and Ⅱ （P＜0.01）.The nitrogen intake,fecal nitrogen,urine nitrogen,nitrogen deposition,net protein utilization and biological value of protein were no significant differences among all groups （P＞0.05）.In conclusion,the appropriate ratios of food to water of dry powder feed of growing Wusuli raccoon dogs was 1∶3.5 to 1∶4.5.