Non‐phytate phosphorus requirements and efficacy of a genetically engineered yeast phytase in male lingnan yellow broilers from 1 to 21 days of age

This experiment was conducted to investigate the requirement of non‐phytate phosphorus (nPP) and efficacy of a genetically engineered yeast phytase in performance and tibia characteristics by male Lingnan Yellow broilers from 1 to 21 days of age. A total of 2640 1‐day‐old male chicks were randomly allotted to one of 11 dietary treatments, which consisted of six replicate floor pens with 40 birds per pen. All treatments had the same levels of all nutrients except for phosphorus and phytase. The control group (treatment 1) was fed the basal diet without dicalcium phosphate or phytase supplementation. Dietary concentrations of nPP were 0.11%, 0.19%, 0.27%, 0.35%, 0.43%, 0.51% and 0.59% respectively for treatments 1, 2, 3, 4, 5, 6 and 7, through addition of dicalcium phosphate (chemistry grade) to the basal diet. Diets 8–11 were supplemented with a genetically engineered yeast phytase 250, 500, 750 U/kg and a commercial phytase product 500 U/kg in basal diet respectively. The results showed that 0.46% and 0.51% nPP were required for maximum body‐weight gain and optimum tibia development indicators respectively. However, 0.59% nPP had a negative effect on bird growth. The equivalency value of the genetically engineered yeast phytase was estimated to be 874 U/kg to liberate 0.1% nPP.     

Effect of macronutrient ratio of the pre‐starter diet on broiler performance and intermediary metabolism

The aim of this study was to investigate the influence of isoenergetic substitution between the three energy delivering macronutrients in pre‐starter diets on performance and intermediary nutrient metabolism in broiler chickens. From hatch until 5 days of age, 600 chicks, collected during peak of hatch, were fed one of the three experimental pre‐starter diets with isoenergetic (13 MJ metabolisable energy/kg) substitutions between fat (43 vs. 108 g/kg), protein (126 vs. 240 g/kg) and carbohydrates (391 vs. 510 g/kg). After 5 days, commercial grower and finisher diets were provided. Pre‐starter composition influenced body weight until slaughter age, although not statistically verifiable. Broilers fed the low protein (LP) pre‐starter had the lowest body weight in relation to chickens on the low carbohydrate or low fat pre‐starter diet. After hatch, chicks on the LP pre‐starter diet were able to use the residual yolk sac more rapidly to fulfil their protein requirement, which is reflected in small intestine and liver development. Also, plasma metabolite levels were influenced mostly by the LP pre‐starter, indicating that the main focus for the requirements of newly hatched chicks should be on proteins. Furthermore, optimal nutrition during the first day’s post‐hatch should take into account the contribution of the yolk.     

早期数量限饲对肉用仔鸡生产性能、胴体品质的影响

试验研究了早期数量限饲对肉用仔鸡生产性能、胴体品质的影响。以320只1日龄AA+肉用仔鸡为试验动物。设4个处理组,每个处理组4个重复,每个重复20只肉仔鸡。对照组根据AA+商品代肉鸡营养标准配制。各处理肉用仔鸡1～7日龄均为自由采食,8～14日龄对照组、限饲90%组、限饲80%组和限饲70%组分别饲喂自由采食量的100%、90%、80%和70%,15日龄恢复自由采食,以后按常规饲养管理。每周末,以重复为单位全部称重。分别于42、49日龄,每个重复随机抽取4只肉用仔鸡禁食12h、称重、屠宰、测定屠体品质。试验结果表明:在第2周,限饲各组肉仔鸡的体重和日增重分别显著低于对照组(P0.05);在第3周,限饲90%组完成补偿生长,体重与对照组差异不显著(P0.05);在第4周,限饲80%和70%组完成补偿生长,体重与对照组差异不显著(P0.05);5、6、7周及2～6、2～7周各组在体重、日增重、日采食量和饲料转化率等都无显著差异(P0.05)。早期数量限饲对肉仔鸡胴体特性没有显著影响(P0.05),限饲70%～80%,具有改善饲料转化效率、胸肌率、腹脂率的作用。     

Effects of Astragalus membranaceus on growth performance,carcass characteristics,and antioxidant status of broiler chickens

Abstract

An experiment was conducted using 720 one-day-old Arbor Acres broiler chickens to evaluate the effects of Astragalus membranaceus root powder (AMP), Astragalus polysaccharides (APS) on growth performance, carcass characteristics, and antioxidant enzymes, and metabolites of blood and liver in broiler chickens. The six dietary treatments included a control that was a corn–soybean meal basal diet; basal diet supplemented with 120 mg/kg antibiotic; 350 mg/kg APS; or 5000, 10,000, or 15,000 mg/kg diet of AMP. Supplementation of 10,000 mg/kg AMP increased average daily gain and feed conversion rate of broilers in grower period (22–42 d) and over the entire experiment compared to basic diet. Responses of antioxidant status to dietary APS and AMP varied depending on the age of the broilers. Beneficial effects of AMP on growth and feed utilization of broilers could be obtained by inclusion of AMP at the rate of 10,000 mg/kg diet.     

喹赛多对山羊生长性能及胴体品质的影响

60只3月龄左右杂交山羊,随机分为6组,空白对照组饲料不添加任何药物,药物对照组饲料添加50 mg/kg喹乙醇,4个试验组饲料中分别添加25、50、150和250 mg/kg喹赛多,试验期90 d.结果表明喹赛多25、50和150mg/kg能改善山羊平均日增重(ADG)4.4%、14.5%和7.2%,提高饲料转化率(FCR)5.9%、12.0%和7.4%.喹赛多250 mg/kg提高FCR 8.6%,但降低ADG 2.1%.喹赛多50 mg/kg组ADG和FCR均高于喹乙醇组.喹赛多50 mg/kg降低山羊腹泻频率39.0%,但随剂量增加,其抗腹泻作用下降.喹赛多25、50、150和250 mg/kg能提高山羊屠宰率2.5%、9.0%、5.0%和1.0%,增加眼肌面积4.8%、34.1%、16.1%和14.0%.喹赛多50 mg/kg组山羊净肉率提高14.0%,高于其他各组.喹赛多各剂量均能显著增高肌肉pH值,平均降低滴水损失值13.7%.可见,喹赛多适宜剂量,尤其50 mg/kg,有较好的促进山羊生长和改善胴体品质的作用.     

Influence of pre‐press solvent‐extracted cottonseed meal supplemented with exogenous enzyme and digestible lysine on performance,digestibility, carcass and immunity responses of broiler chickens

The response of broiler chickens to two levels of endo‐1,4‐β xylanase (EC 3.2.1.8) and endo‐1,3‐β glucanase (EC 3.2.1.6) combination (with and without), three levels of digestible lysine (0.8%, 0.9% and 1.0% with the applicability of ideal protein concept) and two levels of cottonseed meal (CSM; 20% and 30%) were evaluated in 2 × 3 × 2 factorial arrangement. A total of 2448 male Hubbard broiler chicks were fed on practical vegetable‐based mash diets having 2750 kcal metabolizable energy (ME) per kg and 18.5% crude protein (CP) from the age of day 1 to 42. The supplemental enzyme had minimum 1100 units of endo‐1,4‐β xylanase and 100 units of endo‐1,3‐β glucanase/kg of finished diet. The addition of CSM at 30% resulted in increasing arginine to lysine ratio. A decrease in dressing and breast percentages were observed by the addition of 30% CSM. The digestible lysine at 1.0% decreased the body weight (BW) gain and lowered the mortality during day 1 to 21 whereas the BW gain and feed:gain ratio were unaffected among the three digestible lysine levels during day 1 to 42. The antibody titres against Newcastle and infectious bursal disease viruses were improved with the increasing levels of digestible lysine. The enzyme supplementation improved the apparent ME and digestibility coefficient of nitrogen when it was used with 30% CSM. No effect of enzyme, lysine, CSM or their interactions was observed on serum iron, gizzard and liver weights or abdominal fat percentage. The results showed that increasing digestible lysine improved the antibody titre but did not improve the growth performance and carcass characteristics; supplemental enzyme failed to show any improvement in performance of birds fed on CSM‐based diets.     

Effects of thermo‐resistant non‐starch polysaccharide degrading multi‐enzyme on growth performance,meat quality,relative weights of body organs and blood profile in broiler chickens

This research was conducted to study the performance and carcass parameters of broiler chickens fed diets supplemented with heat‐treated non‐starch polysaccharide degrading enzyme. A total of 432 one‐day old Ross 308 broiler chickens were allocated to five treatments: (i) CON (basal diet), (ii) E1: CON + 0.05% multi‐enzyme, (iii) E2: CON + 0.1% multi‐enzyme, (iv) E3: CON + 0.05% thermo‐resistant multi‐enzyme and (v) E4: CON + 0.1% thermo‐resistant multi‐enzyme, each treatment consisted of six replications and 12 chickens in each replication. The chickens were housed in three floor battery cages during 28‐day experimental period. On days 1–7, gain in body weight (BWG) improved by feeding the diets supplemented with thermo‐resistant multi‐enzyme. On days 7–21 and 1–28, chickens fed the diets containing thermo‐resistant multi‐enzyme showed improved (p < 0.05) BWG and feed conversion ratio (FCR) compared to CON group. Supplementing the diets with multi‐enzyme or thermo‐resistant multi‐enzyme affected the percentage of drip loss on d 1 (p < 0.05). Drip loss percentage on days 3 and 5 and also meat colour were not affected significantly. Supplementing the diets with multi‐enzyme or thermo‐resistant multi‐enzyme did not affect the relative weights of organs but compared to CON group, relative weight of breast muscle increased and abdominal fat decreased (p < 0.05). Among measured blood constituents, chickens fed supplemented diets with thermo‐resistant multi‐enzyme showed higher (p < 0.05) IgG. Counts of red and white blood cells and lymphocyte percentage were not affected. In conclusion, the results demonstrated that supplementing pelleted diets with thermo‐resistant multi‐enzyme improved performance of broiler chickens.     

理想氨基酸水平对肉仔鸡生产性能和屠体性状的影响

试验选用1日龄爱拔益加商品代肉仔鸡600只(公母各半),随机分为3个组,每组8个重复,每个重复25只鸡。分别饲喂高、中、低理想氨基酸水平的日粮,研究理想氨基酸水平对肉仔鸡生产性能和屠体性状的影响。结果表明,0~44日龄中氨基酸水平组和高氨酸水平组的出栏重显著高于低氨酸水平组(P<0.05)。高氨基酸水平组腹脂率显著低于低氨基酸水平组41.63%(P<0.05);高氨基酸水平组大腿肉率和净腿肉率均显著高于中和低氨基酸水平组(P<0.05)。     

Effects of dietary supplementation with a chlorella by‐product on the growth performance,immune response,intestinal microflora and intestinal mucosal morphology in broiler chickens

This study aimed to determine the effect of different dietary levels of a Chlorella by‐product (CBP) on the growth performance, immune response, intestinal microflora and intestinal mucosal morphology of broilers. In total, 480 one‐day‐old broiler chickens were randomly allotted to four dietary treatments with four replicated pens consisting of 30 chicks. The basal diet was formulated to be adequate in energy and nutrients. Three additional diets were prepared by supplementing 25, 50 or 75 g/kg of CBP to the basal diet. The diets were fed to the broilers ad libitum for 35 days. Result indicated that increasing inclusion level of CBP improved BW gain (linear, p < 0.05). There was no effect of inclusion level of CBP in diets on total cholesterol, triglyceride, aspartate aminotransferase and alanine aminotransferase levels during the 35 days. Plasma IgG, IgM and IgA concentrations increased (linear, p < 0.05) with inclusion level of CBP in diets. Supplementation of CBP in the diets increased (linear, p < 0.05) the concentrations of Lactobacillus in the caecal content and decreased (linear, p < 0.05) the concentrations of Escherichia coli and Salmonella in the caecal content. Villus height increased (linear and quadratic, p < 0.05) with inclusion level of CBP in diets. Crypt depth increased (quadratic, p < 0.05) with inclusion level of CBP, and a decreased villus height: crypt depth ratio (quadratic, p < 0.05) was observed as inclusion level of CBP in diets increased. The results of the current experiment indicate that dietary supplementation of CBP improves growth performance of birds. Dietary CBP has improving Lactobacillus spp. concentrations in the gastrointestinal tract, plasma immunoglobulin concentrations and intestinal mucosal morphology.     

Effects of soybean oligosaccharide,stachyose, and raffinose on growth performance and cecal microbiota in broiler chickens

This study was conducted to examine the effects of soybean oligosaccharide, stachyose, and raffinose on growth performance and cecal microbiota in broiler chickens. Three-hundred 1-day-old Arbor Acres broiler chickens were randomly assigned to five dietary treatments: a basal diet (control diet); diets supplemented with soybean oligosaccharide, stachyose, or raffinose at levels of 0.6% total sugar content; and diet with soybean meals (positive control). Results showed that feed-to-gain ratio (F/G) was improved (p < 0.05) in broiler chickens that received stachyose, but not raffinose, while addition of soybean oligosaccharide to the diet significantly (p < 0.05) resulted in decreases in the average daily feed intake (ADFI) and average daily gain (ADG). Supplementation with soybean oligosaccharide, stachyose, or raffinose had a positive effect (p < 0.05) on the nutrient digestibility, but not on the blood immune parameters (p > 0.05). The results of the gene sequencing indicated that, at the family level, Ruminococcaceae, Lachnospiraceae, and Lactobacillaceae were comparatively present in all the treatments but the cecal microbial composition was changed after dietary addition of different oligosaccharides. Our study had led to a greater understanding of prebiotic effects of these oligosaccharides on growth and intestinal health.     

不同氨基酸限量水平对肉鸭的生长性能和胴体特征的影响

本研究旨在评估日粮不同氨基酸水平对1～56?d肉鸭生长性能和胴体特征的影响.将平均初始体重为(55.92±0.56)g的800只1日龄肉鸭随机分为5组,每组4个重复,每个重复40只.各组肉鸭在1～21?d时饲喂赖氨酸、蛋氨酸+胱氨酸、苏氨酸水平分别为0.90％+0.75％+0.70％、1.0％+0.80％+0.80％、...     

Wet litter not only induces footpad dermatitis but also reduces overall welfare,technical performance,and carcass yield in broiler chickens

This study investigated whether a high level of footpad dermatitis (FPD) in broiler chickens induced by increased litter moisture content is accompanied by negative effects on technical performance, carcass yield, and other welfare aspects. Litter moisture content was increased by systematically spraying water over the litter from 6 d of age onward (lesion-induction treatment). Results were compared with a control group kept on relatively good quality litter and having a very low prevalence of footpad lesions. Litter quality significantly decreased from 7 d of age onward in the pens with the lesion-induction treatment compared with the control pens. At 21 and 36 d of age, significantly more FPD was observed in the lesion-induction groups compared with the control groups. Technical performance of the broilers was negatively affected for the lesion-induction groups from 28 d of age onward; lesion-induction groups had significantly lower BW gain, feed intake, and water intake and significantly higher FCR compared with control groups. As a result of the lower BW gain, carcass weight was less for the lesion-induction group and significantly more rejections for commercial parts were found. The lesion-induction groups also had significantly more hock burns and breast irritations at d 21 and 36, and were dirtier but had fewer thigh scratches at d 35 compared with the control groups. In addition, locomotion was negatively affected among the lesion-induction group, as they had a higher gait score at d 36 compared with the control group. We concluded that increased litter moisture content not only caused severe FPD but also reduced broiler performance and carcass yield and had a negative effect on other welfare aspects.     

中草药对山羊生长性能和胴体特征的影响

文章旨在研究在山羊日粮中添加中草药对其生长性能和胴体特征的影响.试验将平均体重为(19.22±0.08)kg的45头山羊随机分为3组,每组3个重复,每个重复5头羊.对照组饲喂基础日粮,两个处理组分别用10％的穿心莲茎叶和全珠穿心莲替代苜蓿草,试验共进行14周.结果:饲喂全珠穿心莲的山羊末重、屠体重、采食量和日增重分别较...     

Effects of yeast culture supplementation and the ratio of non‐structural carbohydrate to fat on growth performance,carcass traits and the fatty acid profile of the longissimus dorsi muscle in lambs

The effects of yeast culture (YC) supplementation and the dietary ratio of non‐structural carbohydrate to fat (NSCFR) on growth performance, carcass traits and fatty acid profile of the longissimus dorsi (LD) muscle in lambs were determined in a 2 × 3 full factorial experiment. Thirty‐six Small‐tailed Han lambs were randomly divided into six groups with six replicates per group. The lambs were fed one of the six pelleted total mixed rations (TMRs) for 60 days after 15 adaption days. The six rations were formed by two NSCFRs (11.37 and 4.57) and three YC supplementation levels (0, 0.8 and 2.3 g/kg dietary dry matter). The average daily gain (ADG), dry matter intake (DMI) and feed conversion ratio (FCR) data of each lamb were recorded and calculated. All the lambs were slaughtered for determining carcass traits and fatty acid profile of the LD muscle. DMI was significantly increased (p < 0.05) in a quadratic fashion with 0.8 g/kg of YC supplementation. Carcass weight (CW) and dressing percentage (DP) were significantly increased (p < 0.05) in a linear fashion with 2.3 g/kg of YC supplementation. Animals fed with high‐NSCFR diet had higher (p < 0.05) contents of myristoleic acid (C14:1), pentadecanoic acid (C15:0) and cis‐10‐heptadecenoic acid (C17:1), and lower (p < 0.05) stearic acid (C18:0) content in LD muscle than those fed with low‐NSCFR diet. Moreover, ADG, growth rate (GR), backfat thickness (BFT), percentages of crude fat (CF) and crude protein (CP), SFAs, MUFAs and PUFAs in LD muscle, were significantly affected (p < 0.05) by interaction of dietary NSCFR and supplemental YC level. Overall, YC not only improved the growth performance and carcass traits of the animals but also modified the fatty acid profile of the LD muscle. Furthermore, the effects of YC supplementation may depend on dietary compositions.     

Effect of dietary Moringa oleifera leaves on the performance,ileal microbiota and antioxidative status of broiler chickens

In this study, we investigated the effect of Moringa oleifera leaves (MOL) supplements on the performance, ileal microbiota carcass traits and biochemical and antioxidant parameters of broiler chickens. MOL was added to starter, grower and finisher diets at four levels (0%, 0.5%, 1.0% and 5.0%). A total of 320 one-day-old mixed-sex Cobb-500 broiler chicks were divided equally into four treatment groups, with 5 replicates of 16 chicks each until 42 days of age. Compared to the control group, chicks fed 0.5% and 1% MOL exhibited a higher final body weight (FBW), greater weight gain (BWG), and better average daily gain (ADG). Feed intake (FI) gradually decreased as the inclusion rate of MOL in the broilers' diet increased to 5%. The best feed conversion ratio (FCR), protein efficiency ratio (PER) and performance index (PI) were observed in broilers that were fed the MOL diet. The percentage of abdominal fat in broilers decreased significantly in response to dietary supplementation with MOL. The haematological profile in the MOL group revealed a lower WBC count and lymphocyte percentage but higher heterophil and H/L ratio without affecting haemoglobin and RBC count. The inclusion of MOL increased total serum protein, Ca and P levels but decreased glucose, cholesterol, triglycerides, AST and ALT concentrations. Moreover, dietary MOL increased the activities of GSH, CAT and SOD, GPx and GST while decreasing the TBARS level. The pH value decreased in the ileum of broilers fed the 1% and 5% MOL diet compared to the other treatments. Decreased ileal counts of E. coli, Salmonella and Staphylococcus spp. were observed whereas the total ileal Lactobacillus spp. count increased in broilers fed the MOL diet. In conclusion, the MOL supplement can enhance growth performance and antioxidant status, alter ileal microbiota and protect against enteropathogens with no deleterious effects on the broiler chickens.     

甘草提取物对肉兔生长性能、胴体性状和肉质的影响

文章旨在评估甘草提取物对肉兔生长性能、胴体性状和肉质的影响.试验将平均初始体重为(764.45±17.54)g的240只肉兔随机分为4组,每组3个重复,每个重复20只,即对照组和3个处理组分别饲喂基础日粮、基础日粮+3、6和9 g/kg甘草提取物.试验进行到12周后开展相关数据记录与样品测定.结果:3 g/kg甘草提取...     

水产下脚料对肉鸡生长性能、胴体性状及肠道健康的影响

文章旨在评估日粮添加不同水平的水产下脚料对肉鸡生长性能、胴体性状及肠道健康的影响.试验将504只体重一致的1日龄肉鸡随机分为3组,每组6个重复,每个重复28只.对照组饲喂基础日粮,处理组饲喂水产下脚料添加水平为8％和16％的日粮,对照组与处理组日粮的营养水平保持一致,试验为期6周.结果:T1和T2组42?d肉鸡体重、2...     

补饲马铃薯藤对山羊生长性能、消化率和胴体特征的影响

本研究旨在探讨马铃薯藤饲喂水平对山羊生长性能、养分消化率和胴体特征的影响.试验将平均初始体重为(14.42±0.24)kg的40头山羊随机分为4组,每组5个重复,每个重复2头.T1组仅饲喂干草,T2组饲喂干草+100％马铃薯藤,T3组饲喂干草+50％马铃薯藤+50％浓缩料,T4组饲喂100％浓缩料.在为期10周的饲养试...