Intestinal function and body growth of broiler chickens on maize‐based diets supplemented with mimosa tannins and a microbial enzyme

A study was conducted to evaluate the effects of tannin (0, 5, 15, 20 and 25 g kg^?1 diet) and a microbial enzyme supplement (MES) on the feed consumption, body growth and digestive physiology of broiler chickens between hatch and 22 days of age. Feed intake, body weight and body weight gain declined (p < 0.001) with an increase in dietary tannin content. Feed conversion efficiency was increased (p < 0.001) in line with dietary tannin level, up to 15 g kg^?1 diet. There were no significant effects of dietary treatment on the protein content of pancreatic tissue or activities of pancreatic and jejunal enzymes. The ileal digestibilities of energy, protein, arginine, alanine and leucine were reduced (p < 0.001) as dietary tannin level rose to 20 g kg^?1 diet and beyond. The digestibilities of methionine and phenylalanine were also negatively affected (p < 0.01) at the highest level of dietary tannins, while phosphorus digestion was improved (p < 0.05) on diets containing tannin. Apart from an increase (p < 0.01) in the protein content of the jejunal mucosa of birds on the diet with 20 g tannin kg^?1 diet, there were no significant effects of the MES on most of the variables assessed. The results demonstrate the negative effects of tannin, especially at high levels of inclusion in the diet. However, neither tannins nor MES influenced the activities of digestive enzymes assessed, suggesting that a wider range of factors may be involved in regulating the effects of tannins on poultry. Copyright © 2004 Society of Chemical Industry     

Effects of mannan oligosaccharide or antibiotics in neonatal diets on health and growth of dairy calves

Seventy-two Holstein calves were used to study the effect of feeding antibiotics or mannan oligosaccharides (MOS) in milk replacer. Calves were fed a 20% protein, 20% fat milk replacer containing antibiotics (400 g/ton neomycin + 200 g/ton oxytetracycline), MOS (4 g of Bio-Mos/d), or no additive (control) for 5 wk. Milk replacer was reconstituted to 12.5% dry matter and fed at 12% of birth weight during wk 1 and 14% of birth weight in wk 2 to 5. Fecal scores were monitored 3 times per week; body weight, heart girth, withers height, hip height, and hip width were measured at birth and weekly to 6 wk of age. Addition of MOS or antibiotics increased the probability of normal scores for fecal fluidity, scours severity, and fecal consistency as compared to control calves during the course of the study. Consumption of calf starter increased at a faster rate in calves fed MOS, and these calves consumed more calf starter after weaning (wk 6), than those fed antibiotic. No treatment differences in growth measures, total blood protein, or blood urea nitrogen were detected during the trial. Addition of MOS or antibiotics to milk replacer improved fecal scores in calves. Feed intake was improved in MOS-fed calves compared to antibiotic-fed calves, but this difference did not result in growth differences during the experimental period. The results suggest that antibiotics in milk replacers can be replaced with compounds such as mannan oligosaccharides to obtain similar calf performance.     

Modulation of post-hatch growth and immunity through in ovo supplemented nutrients in broiler chickens

BACKGROUND: Early post‐hatch growth and immunity were assessed through in ovo supplementation of nutrients: amino acids (AA), trace elements (TE), fatty acids and vitamins (FAV) grouped under humoral immunity (HI) or cell‐mediated immunity (CMI) on the 18th day of incubation at the broad end of the egg using a 25 mm needle. RESULTS: Hatchability in AA groups was better than TE and FAV groups. CMI groups had better hatchability than HI groups. AA and TE groups had higher chick‐to‐egg weight ratio (P < 0.01) than the FAV group. At 3 weeks of age, a higher body weight (P < 0.01) was recorded in AA for CMI, TE for HI and FAV for HI groups. FAV‐injected chicks had a higher bursa weight at hatch, but TE chicks had higher thymus weight at the 3rd week of age. Humoral immune response was not different in in ovo injected chicks compared to control. CMI was higher (P < 0.01) in AA for CMI, TE for CMI and FAV for CMI or HI nutrient‐injected chicks. CONCLUSIONS: In ovo injection of AA for CMI and TE for HI may accelerate growth of broiler chickens. In ovo injection of AA, TE or FAV may modulate CMI in chicks. Copyright © 2011 Society of Chemical Industry     

载锌沸石对肉鸡生产性能、抗氧化功能及其相关基因表达的影响

研究载锌沸石(Zn CP,锌含量为15.5 mg/g)对肉鸡生产性能、肝脏锌沉积、抗氧化功能及其相关基因表达的影响,探讨Zn CP作为抗生素替代品的可行性。300只1日龄AA(Arbor Acres)肉鸡随机分成5组,每组6个重复,每个重复10只鸡,试验期为42 d。试验日粮:1)对照组,基础日粮(含Zn SO4,锌含量为60mg/kg);2)基础日粮+抗生素(40 mg/kg金霉素);3)基础日粮+0.1%Zn CP;4)基础日粮+0.2%Zn CP;5)基础日粮+0.4%Zn CP。结果表明,与对照组相比,不同剂量Zn CP显著提高肉鸡前期体增重(P0.05),0.1%和0.2%的Zn CP显著提高21 d肝脏T-SOD和Cu Zn-SOD的活性(P0.05),0.2%的Zn CP显著降低21 d肝脏MDA含量(P0.05),抗生素组和Zn CP组均能显著提高21 d肝脏T-AOC(P0.05);与抗生素组相比,0.1%和0.2%的Zn CP显著降低21 d肝脏MDA含量(P0.05),显著提高21 d肝脏T-SOD的活性(P0.05),0.1%的Zn CP显著提高42 d肉鸡肝脏Nrf2 mRNA的相对表达量(P0.05)。与对照组和抗生素组相比,0.2%的Zn CP显著降低42 d肉鸡肝脏MDA含量(P0.05)。结果提示,肉鸡日粮中添加Zn CP能提高生产性能,效果等同或优于抗生素;Zn CP可能通过提高Keap1/Nrf2/ARE/抗氧化酶信号通路关键基因Nrf2的表达量来提高肉鸡的抗氧化能力;本试验条件下,日粮中Zn CP以0.1%和0.2%的添加量较好。     

Low‐protein amino acid‐supplemented diets in broiler chickens: effects on performance,carcass characteristics,whole‐body composition and efficiencies of nutrient utilisation

Two concurrent trials were conducted to investigate the influence of low‐protein amino acid‐supplemented diets on the performance, carcass characteristics, whole‐body composition and efficiencies of nutrient utilisation by the male broiler chicken from age 3 to 6 weeks. The first trial comprised five isoenergetic (13.0 MJ kg⁻¹) diets containing 225 (control), 210, 190, 172 or 153 g kg⁻¹ crude protein (CP) supplemented with essential amino acids (EAAs) to meet the minimum National Research Council recommendations. In the second trial a composite mixture of non‐essential amino acids (NEAAs) was added to the lower‐CP diets (ie 210–153 g kg⁻¹) such that they became isoproteinous (N × 6.25) with the 225 g kg⁻¹ control. Neither the lowering of dietary CP nor NEAA supplementation had any significant influence on weight gain or the relative weights of the various carcass cuts. However, chicks fed the lowest‐CP diets consumed more feed (P ≤ 0.05) and had poorer (P ≤ 0.05) feed conversion efficiency (FCE). NEAA supplementation enhanced FCE to the control levels. Whole‐body compositional analysis showed that lowering dietary CP increased (P ≤ 0.01) total body fat in a linear fashion (P ≤ 0.001; r = −0.72). Equalising dietary CP with the control (ie maintaining identical energy/protein ratio) by NEAA supplementation did not correct for the fat deposition. Total body protein (g kg⁻¹) was identical with the control with or without NEAA supplementation. Dietary energy, protein retention efficiency (PRE) and protein efficiency ratio (PER) were more efficient (P ≤ 0.01) in the lower‐protein diets, while NEAA supplementation significantly (P ≤ 0.01) decreased the efficiency of N utilisation. Reducing dietary CP from 225 to 153 g kg⁻¹ decreased N excretion in a highly significant linear fashion (P ≤ 0.001; r = 0.73). The nutritional and environmental implications of the increased body fat deposition on the one hand and the decreased N excretion on the other in the low‐protein‐fed chickens are discussed and the need to harmonise these apparently conflicting interests is emphasised. © 2000 Society of Chemical Industry     

Utilisation of two varieties of full‐fat and simulated soyabeans in meal and pelleted diets by broiler chickens

Full‐fat soyabeans (FFSB) (Glycine max) of two varieties, TGX 1440/^E and M‐351, and recombined soyabean meal and oil (SBMO, simulated soyabeans) along with a basal diet were evaluated in a growth and digestibility study designed to examine energy and nutrient digestibility and growth performance of broiler chickens fed the soyabean diets presented as meal or pellets. The soyabean products were incorporated into the basal diet in a 40:60 ratio (product/basal). The resulting eight experimental diets were assessed in a growth trial covering the starter to the finisher phase (1–8 weeks) of the broiler rearing period, during which daily weight gain, feed consumption and feed conversion efficiency were measured. Two digestibility trials were conducted at the starter (1.5–2 weeks) and finisher (7.5–8 weeks) phases of the broiler rearing. Apparent metabolisable energy (AME) and apparent fat (AFD), nitrogen (AND) and dry matter (ADD) digestibilities of diets were determined. Data on carcass and gut measurements were also obtained. The bird rearing phase had a significant (P ≤ 0.001) effect on energy and nutrient digestibility of diets and soyabean products, with the finisher broilers yielding higher values. Mean AME values for FFSB were 16.1 vs 13.6 MJ kg⁻¹ DM for the finisher and starter broilers. Pelleting of diets improved AFD (P ≤ 0.001) and AME (P ≤ 0.10). Significant interaction (P ≤ 0.01) between diet and feed form resulted in improvement in fat digestibility of pelleted FFSB diets but not that of SBMO diets. Carcass fat (P ≤ 0.01) and breast weight (P ≤ 0.05) were increased and gizzard weight decreased (P ≤ 0.01) in birds given the pelleted diets compared with those on meal diets. Birds fed the TGX FFSB diets had significantly lower dietary fat and nitrogen digestibilities and heavier weight of the small intestine than those on the M‐351 diets, thus suggesting varietal differences in the structure and nutritional value of soyabeans. © 2000 Society of Chemical Industry     

Growth performance,nutrient digestibility and immune response of broiler chicks fed diets supplemented with a culture of Lactobacillus bulgaricus

BACKGROUND: Probiotics are being developed for use in animal feed to enhance production performance and prevention of gastrointestinal infections. The ban on using antibiotics as growth promoters, antibiotic resistance and the inherent problems of developing new vaccines make a compelling case for developing alternatives for in‐feed antibiotics. The alternatives of choice have to be considered under the environmental conditions of the animal. Among the probiotics in use today, Lactobacillus has been shown to play a vital role in disease prevention, immune enhancement, improved growth and carcass yield in poultry. The present study investigates the effect of Lactobacillus bulgaricus (LB)‐based probiotic on the growth performance, nutrient digestibility and immune response of broilers under tropical environmental conditions. RESULTS: Broilers fed LB diets consumed more feed (P < 0.05) and had greater body weight gain than the control group. Feed/gain ratio improved significantly (P < 0.05) with the 20, 40 and 60 mg kg^?1 LB diets compared with the control or 80 mg kg^?1 LB diet. The apparent digestibilities of nitrogen and fat increased with LB supplementation. However, there was no significant difference (P > 0.05) in fibre digestibility. White blood cell count increased significantly in broilers fed higher levels (>40 mg kg^?1) of LB compared with the control group. Antibody production measured as antibody titre against Newcastle disease vaccine showed a curvilinear response over the range of LB concentrations examined. CONCLUSION: The results indicate that LB addition to broiler chick diets significantly improved growth performance, increased nutrient digestibility and stimulated humoral immune response. Copyright © 2008 Society of Chemical Industry     

Production responses and serum lipid concentration of broiler chickens fed diets based on oat bran and extracted oat bran with and without enzyme supplementation

Broiler chickens were fed diets based on oat bran or oat bran that had been extracted with ethanol in order to remove tocotrienols and other ethanol-soluble components. The diets were fed ad libitum with and without a supplementary fibre degrading enzyme, except for the enzyme-supplemented diet based on oat bran which was fed at a restricted level equal to the intake of chickens fed the corresponding unsupplemented diet. Enzyme supplementation dramatically improved chicken live weights and feed conversion efficiencies and also feed intake for those fed ad libitum. Chickens fed the unsupplemented diets had low and similar serum triglyceride and cholesterol concentrations whereas birds fed enzyme-supplemented diets had higher serum cholesterol concentrations. Results obtained indicate that, in the present study, the dietary fibre (mainly soluble mixed-linked (1→3), (1→4)-β-D-glucans) had a greater influence on serum cholesterol concentrations than tocotrienols and other ethanol-soluble components, which were effectively extracted by the procedure employed. The importance of meal frequency was also demonstrated by the high triglyceride and serum cholesterol concentrations obtained for chickens fed on a restricted basis.     

Fatty acid profile and cholesterol content of egg yolk from chickens fed diets supplemented with purslane (Portulaca oleracea L.)

BACKGROUND: The aim of the present study was to evaluate the effects of purslane on egg production, egg weight, feed efficiency, yolk fatty acid composition, and egg cholesterol content in laying hens. MATERIAL AND METHODS: Sixty 80‐week‐old layers were allocated randomly to receive diets supplemented with 0 (control), 10 g kg^?1 or 20 g kg^?1 dried purslane for 84 days. Egg weights and egg production in the groups were recorded daily, whereas feed intake was measured weekly. RESULTS: Diet supplemented with 20 g kg^?1 purslane significantly decreased body weight of the chickens compared to the control. Inclusion of purslane at the level of 10 g kg^?1 or 20 g kg^?1 into the diet significantly (P < 0.05) improved egg weight compared to the control. Chickens fed the diet including 20 g kg^?1 purslane had a significantly (P < 0.05) higher egg production and improved feed efficiency compared to the control. Cholesterol content of eggs from the hens fed 0, 10 or 20 g kg^?1 did not differ and was 10.45, 9.51 or 9.51 mg g^?1 dried egg yolk, respectively. Inclusion of purslane at the level of 20 g kg^?1 into the diet significantly (P < 0.05) increased ω‐3 fatty acids such as C18:3(ω‐3) and C22:6(ω‐3). The ratio of ω‐6 to ω‐3 also was significantly (P < 0.05) lower in the eggs from chickens fed 10 g kg^?1 or 20 g kg^?1 purslane supplemented diets compared to the control. CONCLUSION: This study showed that adding dried purslane to the diet of laying hens significantly increased egg production and egg weights although there was no reduction in the egg cholesterol concentration. This study also showed that inclusion of purslane into diet enriched eggs with ω‐3 fatty acids and decreased the ratio of ω‐6/ω‐3 in the yolk. Copyright © 2010 Society of Chemical Industry     

Production results,serum cholesterol concentration and carcass composition of broiler chickens fed diets based on bran or inner endosperm from oats with and without enzyme supplementation

Broiler chickens were fed diets based on bran or inner endosperm from oats (Avena sativa L), given with or without a supplementary fibre-degrading enzyme, in order to study the effects of the dietary fibre on production results, carcass composition and serum cholesterol concentration. Enzyme supplementation of the oat-bran-based diet significantly improved production results and caused an increase in total serum cholesterol concentration and carcass fat whereas carcass crude protein and water content decreased. On enzyme supplementation of the diet based on inner endosperm, a significant although less pronounced improvement in production results was obtained. Chickens fed the inner endosperm diet generally had higher total serum cholesterol concentrations which increased further on enzyme supplementation. Carcass fat content also increased on enzyme supplementation, and at day 27 chickens fed the enzyme-supplemented diet based on inner endosperm had the highest carcass fat content in comparison with all other diets. The results show that dietary fibre exerts a greater influence on total serum cholesterol concentration than energy or fat intake since chickens fed the enzyme-supplemented oat-bran diet had the highest intake of metabolisable energy and fat but still displayed lower total serum cholesterol concentrations than chickens fed the enzyme-supplemented low fibre diet based on inner endosperm.     

亚甲基水杨酸杆菌肽对白羽肉鸡生长性能和肠道菌群结构的影响

亚甲基水杨酸杆菌肽（bacitracin methylene disalicylate, BMD）具有良好的抑菌活性与安全性,可作为一种药物添加剂用于预防和治疗动物疾病。然而,目前关于BMD对白羽肉鸡的生长性能和肠道菌群结构的影响尚不明确。作者选用3日龄健康白羽肉鸡作为实验对象,分别在基础饲粮上添加50 mg/kg金霉素制剂与高（60.0 mg/kg）、中（40.0 mg/kg）、低（20.0 mg/kg）剂量的BMD进行比较饲喂管理。记录28 d内白羽肉鸡料重比变化,利用第二代高通量测序技术对28 d的白羽肉鸡肠道微生物菌群和组成变化进行测序分析,比较各组间与组内的肠道微生物多样性及主要优势菌群相对丰度差异。结果发现,饲喂不同剂量的BMD和金霉素制剂对白羽肉鸡的生长性能均有一定影响,饲喂60.0 mg/kg的BMD时,白羽肉鸡料重比最低,效果最佳。同时,饲喂BMD与金霉素制剂对白羽肉鸡的肠道菌群也产生了一定影响,造成了菌群多样性下降、丰度上升。与空白组相比,添加BMD和金霉素后拟杆菌门、软壁菌门的优势菌群显著上升（P<0.05）,而厚壁菌门显著下降（P<0.05）。在属水平上,Fournierella的相对丰度显著上升（P<0.05）,而粪杆菌属的相对丰度显著下降（P<0.05）。研究结果表明,饲喂BMD对白羽肉鸡的生长性能和肠道菌群结构均有促进作用,能够有效降低白羽肉鸡料重比且能够促进肠道菌群的微生态健康。     

日粮添加蛋氨酸对宫内发育迟缓生长猪肠道发育和抗氧化功能的影响

目的：研究蛋氨酸对宫内发育迟缓（intrauterine growth retardation,IUGR）生长猪肠道发育和抗氧化功 能的调节作用。方法：30 头正常初生体质量（normal birth weight,NBW）和60 头IUGR仔猪于21 日龄断奶,分别随 机分成3 个处理组,即NBW-CON组（NBW仔猪饲喂基础（control,CON）日粮）,IUGR-CON组（IUGR仔猪饲喂 基础日粮）,IUGR-MET组（IUGR仔猪饲喂蛋氨酸（methionine,Met）日粮）,每个处理组6 个重复,每个重复5 头 猪,实验期为84 d。结果：IUGR-CON组猪空肠和回肠绒毛高度（villus height,VH）、空肠绒毛表面积、回肠蔗 糖酶和麦芽糖酶活力、空肠OCLN mRNA相对表达量较NBW-CON组猪显著降低（P＜0.05）。与NBW-CON组猪 相比,IUGR-CON组猪空肠丙二醛（malondialdehyde,MDA）含量显著升高（P＜0.05）,空肠还原型谷胱甘肽 （reduced glutathione,GSH）含量和GSH/氧化型谷胱甘肽值显著降低（P＜0.05）,回肠超氧化物歧化酶活力 显著降低（P＜0.05）。日粮添加蛋氨酸可显著增加IUGR猪空肠VH,升高回肠麦芽糖酶活力,上调空肠OCLN mRNA相对表达量（P＜0.05）。同时,蛋氨酸可显著缓解IUGR介导生长猪空肠MDA含量升高与GSH含量降低 （P＜0.05）。结论：蛋氨酸可降低IUGR猪肠道脂质过氧化程度,改善肠道抗氧化能力,一定程度上缓解了 IUGR对生长猪肠道发育的不良影响。     

在不同营养水平日粮中添加益生菌对肉鸡抗氧化功能、黏膜免疫及回肠菌群的影响

采用2×2因素设计,研究在不同营养水平日粮中添加益生菌对肉鸡免疫器官指数、血清和肠黏膜抗氧化性能、肠黏膜IgG和SIgA及回肠菌群的影响,评价益生菌在宿主内的免疫效应及其机理。试验选用1日龄AA肉鸡320只,分成4组,每组10个重复,每个重复8只,饲喂以下4种日粮:(1)正对照组(NC):基础日粮;(2)负对照组(LC):低能低蛋白日粮,使基础日粮的代谢能降低320 kJ/kg,粗蛋白均降低0.85%;(3)试验1组(NP):基础日粮+0.01%益生菌;(4)试验2组(LP):低能低蛋白日粮+0.01%益生菌。结果表明,在不同营养水平下,益生菌能提高21 d肉鸡的胸腺指数(P<0.01)、脾脏指数和法氏囊指数(P<0.05),但不影响42 d免疫器官指数(P>0.05),可显著提高肉鸡21 d血清和肠黏膜总超氧化物歧化酶(T-SOD)的活性(P<0.05),降低肉鸡21 d血清丙二醛(MDA)的含量(P<0.01),对21 d肠黏膜MDA含量也有降低趋势(P=0.057),能极显著提高42 d血清T-SOD活性和总抗氧化能力(T-AOC)(P<0.01),显著降低42 d血清和肠黏膜MDA的含量(P<0.05);在不同营养水平日粮中添加益生菌对肠黏膜IgG的含量有提高趋势(P=0.077),显著提高42 d肠黏膜IgG和SIgA含量(P<0.05),能显著降低21 d、42 d回肠大肠杆菌数量(P<0.05),极显著提高21 d回肠乳酸杆菌的数量(P<0.01),对42 d回肠乳酸杆菌数量没有显著影响(P>0.05)。结果提示,在不同营养水平下添加益生菌能促进肉鸡前期的免疫器官生长和发育,增强血液和肠黏膜的抗氧化功能,促进肠黏膜免疫球蛋白分泌,并能促进回肠乳酸杆菌增殖,抑制大肠杆菌增殖。