不同比例寡肽对肉仔鸡生长及相关激素分泌的影响

为探讨不同比例寡肽对肉仔鸡生长发育及相关激素分泌影响,选用体重相近的1日龄AA公肉仔鸡360只,随机分为6处理,每处理6个重复,每重复10只鸡,6处理肉鸡分别采食不同比例氨基酸与肽混合物、酪蛋白和游离氨基酸日粮,试验期为3周。结果表明:0~3龄肉鸡,肽氨基酸混合物组和酪蛋白组分别比氨基酸组、纯肽组生长速度提高了0.17%~18.70%,采食量增加0.89%~11.83%,饲料转化率改善3.18%~13.66%;血清激素检测表明:随着日粮中寡肽比例变化,血清中T3、T4、GHI、GF-I发生规律性变化。由此可以推论:蛋白质的营养是氨基酸营养,更是寡肽营养,寡肽在促进动物生长方面起重要作用。     

乳酸菌株植物乳杆菌和粪链球菌对肉鸡免疫性能的影响

将植物乳杆菌和粪链球菌2株乳酸菌分别添加到肉鸡饲料中,通过检测免疫器官指数、胸腺和脾脏的T细胞百分数、白细胞吞噬率、红细胞花环率、血清中新城疫(ND)血凝抑制(HI)抗体效价等指标,探讨了乳酸菌对肉鸡免疫性能的影响.结果表明,2株乳酸菌均能够促进肉鸡胸腺、脾脏和法氏囊的发育,增强白细胞的吞噬功能,增加胸腺和脾脏中的T细胞数,提高E-C3bR和E-ICR的花环形成率,以及提高机体产生ND疫苗HI抗体的水平.     

植物粉剂对肉鸡生长性能、肠道菌群数量和肌肉脂肪酸的影响

文章旨在评估植物粉剂(大蒜粉和石莲花粉)对1～42?d肉鸡生长性能、肠道菌群和肌肉脂肪酸组成的影响.试验选择平均初始体重为(48.33±0.47)g的1日龄商品肉仔鸡640只,随机分为4组,每组5个重复,每个重复32只.对照组饲喂基础日粮,药物组肉鸡饲喂基础日粮,但通过饮水补充2?mg/L维吉尼亚霉素水溶剂,大蒜粉组肉...     

甘草多糖的提取及其对肉仔鸡免疫功能的影响

用水煮法和索氏提取法2种提取方法从甘草根粉中提取水溶性甘草多糖,并对提取甘草多糖的得率及稳定性进行比较,筛选出甘草多糖更简单高效的提取工艺;将所提取的甘草多糖以不同浓度和给药途径应用于试验动物,并测定其对肉仔鸡体重、血清中新城疫抗体水平、血液巨噬细胞吞噬功能的影响.结果表明,甘草多糖能促进肉仔鸡体重增加,提高其血清中新城疫抗体水平和血液中巨噬细胞吞噬功能.与黄芪多糖比较的结果表明,甘草多糖对肉仔鸡体重增加、巨噬细胞吞噬功能增强的影响水平和黄芪多糖相似;而促进血清中新城疫抗体水平的作用不及黄芪多糖.     

牛磺酸对肉仔鸡生产性能和免疫功能的影响

以添加不同水平的牛磺酸日粮饲喂艾维茵商品代肉仔鸡,探讨牛磺酸对肉仔鸡生产性能和免疫功能的影响及最佳添加水平和添加时间。结果表明：添加牛磺酸可不同程度地提高肉仔鸡生产性能,其中以添加0.10%牛磺酸效果最佳,且前期添加效果优于后期。添加0.10%和0.20%的牛磺酸,可显著促进3周龄腔上囊和脾脏的生长发育;对胸腺的生长发育具有促进作用,但效果不显著;可促进6周龄肉仔鸡胸腺和脾脏的生长发育,对胸腺影响效果极显著;添加0.10%的牛磺酸对脾脏影响显著;而对6周龄肉仔鸡腔上囊的生长发育有抑制作用。添加牛磺酸可提高3周龄肉仔鸡血清球蛋白水平,从而提高机体的免疫功能。     

Modification of the human–broiler relationship and its potential effects on production

The present study was designed to investigate the effects of additional human contact (AHC) on the human–animal relationship (HAR) in broilers and on the birds’ productivity. A total of 1558 broiler one-day-old chicks were distributed into 12 equally sized pens at two different stocking densities (SDs), calculated on estimated weight at slaughter (4 pens with 32?kg/m² and 8 pens with 16?kg/m²). Six groups (2 high and 4 low SDs) received AHC, which consisted of 30-min sessions with visual human contact three days/week. The remaining six groups received as little human contact as possible and served as controls. A touch test was used to assess the human–broiler relationship and the production parameters measured were growth rate, mortality, feed consumption and feed conversion. The AHC treatment had a positive effect on the quality of the HAR but failed to affect any production parameter.     

Evaluation of different water flow rates of nipple drinkers on broiler productivity

Watering systems utilized in broiler production can impact bird performance. Many companies have increased water flow rates (WFR) in their nipple drinkers (ND) system during brooding above the manufacturers recommended level, then make adjustments in WFR during the grow period. This has increased moisture and early caking problems in litter. The objective of this study was to determine how birds perform on different WFR rates during brood and grow periods while observing litter condition. Seven WFR treatments were evaluated for broilers reared from 1 to 42 d age: 50 mL/min, 75 mL/min, 100 mL/min, 120 mL/min, 50 mL/min 1 to 7 d increasing to 75 mL/min 8 to 42 d, 75 mL/min 1 to 7 d increasing to 100 mL/min 8 to 42 d, and 100 mL/min 1 to 7 d increasing to 120 mL/min 8 to 42 d. Chicks were identified and randomly allocated in a randomized complete block design. BW, cumulative feed consumption (FC), FCR (feed:BW), litter moisture (%), and litter moisture under the ND were determined weekly to 42 d. Mortality (MO) was recorded daily. Birds tended to have heavier BW on d 35 when (P = 0.08) on the higher WFR (75, 100, and 120 mL/min) in comparison to birds on the lowest WFR (50 mL/min). No differences were observed for FC, FCR, or MO. Birds on treatments with higher WFR (100 and 120 mL/min) and treatments which were increased to higher WFR (75 to 100 mL/min and 100 to 120 mL/min) utilized greater amounts of water as compared to birds receiving lower WFR (50 and 75 mL/min). The 100 and 120 mL/min WFR resulted in higher percent litter moisture (P ≤ 0.01) under the ND but decreased at the end of the growing period. In conclusion, as birds become heavier, they attempt to utilize larger amounts of water from ND with greater WFR without any beneficial effect on bird performance. As WFR increase, litter moisture under the ND will initially increase but then decrease as the birds age.     

Study on the Distribution of Glial Fibrillary Acidic Protein in Intestine of Yellow Feather Broiler

The experiment was conducted to explore the distribution of glial fibrillary acidic protein (GFAP) in Yellow feather broiler,and to investigate the morphological characteristics of glial cells of chicken. The distribution of GFAP was studied by immunohistochemistry SABC-AP method. The results showed that GFAP were expressed strong positively in chicken small intestinal mucosa epithelium, intestinal gland cell cavity surface, submucosal plexus and myenteric plexus; The expressions of GFAP were positive in the mucosal lamina propria and myenteric nerve plexus around the blood vessel; In avian escherichia sticky epithelial membrane, colorectal adenocarcinoma,GFAP were expressed positively, and the expressions were strong positive in mucosa epithelium, submucosal plexus and myenteric plexus. GFAP was one of the specific marker of enteric glial cells, and the observation of distribution of GFAP in chicken intestinal tract was help for elucidating the enteric glial cells in the distribution of the intestine and providing the morphological basis for the study of chicken glial cell function.     

Pathogen re-colonization of in-house composted and noncomposted broiler litter

In-house litter composting has been reintroduced to the industry and shown to reduce bacteria by as much as 2 orders of magnitude. Other industries have demonstrated that pathogens can recolonize a waste-residual when microbial competition has been reduced or inhibited following composting. Poultry growers, in the process of shifting to in-house composting for pathogen control, should be aware of this potential problem. A laboratory microcosm study investigated pathogenic bacteria recolonization into composted and noncomposted broiler litter over a simulated broiler grow-out cycle. Objectives were to: 1) determine colonization potential for zoonotic and poultry bacterial pathogens, 2) identify beneficial bacteria which reduce pathogen recolonization, and 3) identify the effects of ammonia on pathogen recolonization. Composted broiler litter allowedListeria andCampylobacter to colonize within the first 2 wk of the grow-out period while noncomposted litter resisted colonization. Colonization was nearly identical by the end of the grow-out period, and showed that bacterial pathogens had essentially been overtaken by commensal or normal bacteria. 16S rRNA libraries demonstrated reductions in Proteobacteria associated with composted litter (48 vs. 16%), which may indicate that this phylum occupies a niche which zoonotic pathogens prefer to occupy. Ammonia generation neither inhibited nor promoted bacterial colonization, as levels were high for both litter treatments. This study neither suggests nor condemns the continued use of this cost-effective, litter-treatment process; findings suggest that while the beneficial microbial population was initially reduced, it quickly recovered and pathogen colonization was neither enhanced nor inhibited because of this. This study demonstrates that the recently adopted in-house composting process may continue to be used, provided poultry health gains continue to be seen.     

高温对肉用仔鸡生产性能和某些血清生化指标的影响

本文研究了高温对肉用仔鸡生产性能和５种血清生化指标的影响。结果表明：不同生长时期的高温对肉用仔鸡的生产性能和血清生化指标有不同程度的影响。如２２２４日龄肉用仔鸡在３４±１．５℃下，采食量减少，体重、血清总蛋白和白蛋白均显著下降（Ｐ＜０．０５），饲料转化率、血糖、球蛋白和胆固醇无显著变化。２２４２日龄给予高温处理，鸡采食量和饲料转化率均降低，体重、血糖、血清总蛋白、白蛋白和球蛋白均显著下降或极显著下降（Ｐ＜０．０５或Ｐ＜０．０１），胆固醇仍无明显变化。４０４２日龄给予高温处理，鸡的生产性能和各项血清生化指标均显著下降或极显著下降（Ｐ＜０．０５或Ｐ＜０．０１）。