几内亚热带气候对海波罗肉用仔鸡长期耗料量及料肉比影响的研究

分4批从孵出的海波罗鸡雏中选出888只公母混合雏，每批222只，研究几内亚热带气候对海波罗肉仔鸡生长期耗料量的影响。结果表明，4批鸡的整个试验中的累计耗料量分别为4745.58g/只、4507.44g/只、4682.73g/只和4545.77g/只。第Ⅱ、Ⅲ和Ⅳ批鸡的累计耗料量比第Ⅰ批鸡分别少5.28%、1.13%和4.40%，第Ⅱ和第Ⅳ批累计耗料量比第Ⅲ批分别少4.11%和3.23%，第Ⅱ批累计耗料量比第Ⅳ批的少0.5%，比第Ⅰ、Ⅲ和Ⅳ批偏少。4批鸡4周龄料肉比分别为1.23、2.03、1.90和1.67，饲料报酬都高，7周龄分别为3.78、2.97、2.56和2.52，除第Ⅰ批外，各批7周龄饲料报酬较高。在整个试验期，4批鸡1－7周龄的平均累计耗料量为4622.88g/只，其平均累计料肉比为2.28g，累计耗料量比海波罗的标准少217.12g，即4.70%。由于几内亚热带气候影响，本试验鸡采食量少，料肉比较低。     

几内亚热带气候对海波罗肉用仔鸡生长速度的影响

为了解几位亚热带气候对海波罗肉仔鸡生长速度的影响，为将来开发几内亚的肉鸡生产而进行本试验。由本试验4批鸡的生长速度与其它地方的生长速度比较，可以说明：几内亚热带气候对海波罗的肉仔鸡生长速度的影响不大。鸡在几内亚热季或雨季饲养时，适应性较大，生长速度较快，增重高峰期出现早，相对增重符合家禽一般的生长发育规律。     

几内亚热带气候对海波罗肉用仔鸡长期耗料量及料肉比影响的研究

分4批从孵出的海波罗鸡雏中选出888只公母混合雏,每批222只,研究几内亚热带气候对海波罗肉仔鸡生长期耗料量的影响.结果表明,4批鸡的整个试验中的累计耗料量分别为4 745.58 g/只、4 507.44 g/只、4 682.73 g/只和4 545.77 g/只.第Ⅱ、Ⅲ和Ⅳ批鸡的累计耗料量比第Ⅰ批鸡分别少5.28%、1.13%和4.40%,第Ⅱ和第Ⅳ批累计耗料量比第Ⅲ批分别少4.11%和3.23%,第Ⅱ批累计耗料量比第Ⅳ批的少0.5%,比第Ⅰ、Ⅲ和Ⅳ批偏少.4批鸡4周龄料肉比分别为1.23、2.03、1.90和1.67,饲料报酬都高,7周龄分别为3.78、2.97、2.56和2.52,除第Ⅰ批外,各批7周龄饲料报酬较高.在整个试验期,4批鸡1～7周龄的平均累计耗料量为4 622.88 g/只,其平均累计料肉比为2.28 g,累计耗料量比海波罗的标准少217.12 g,即4.70%.由于几内亚热带气候影响,本试验鸡采食量少,料肉比较低.     

几内亚热带气侯对海波罗肉用仔鸡生长速度的影响

为了解几位亚热带气候对海波罗肉仔鸡生长速度的影响,为将来开发几内亚的肉鸡生产而进行本试验.由本试验4批鸡的生长速度与其它地方的生长速度比较,可以说明几内亚热带气候对海波罗的肉仔鸡生长速度的影响不大.鸡在几内亚热季或雨季饲养时,适应性较大,生长速度较快,增重高峰期出现早,相对增重符合家禽一般的生长发育规律.     

EM发酵饲料对肉用仔鸡增重的影响

按体重对等原则,将２００只４周龄的京黄肉仔鸡分成４组进行饲养试验,各组处理为：对照组饲喂基础饲料,试验Ⅰ、Ⅱ、Ⅲ组中分别添加占日粮总重１０％,２０％,１００％的ＥＭ发酵料。结果表明,８周末的增重Ⅰ、Ⅱ组极显著地高于Ⅲ组和对照组（Ｐ＜０．０１）,Ⅱ组显著高于Ⅰ组（Ｐ＜０．０５）,且Ⅰ、Ⅱ组的料肉比明显低于Ⅲ组和对照组。     

贵妇鸡若干种质特性的研究

本试验对贵妇鸡早期生长发育等有关指标进行观测，以揭示该鸡种质特点及性状相关。并应用多元回归分析方法探讨体斜长、胸角、胸骨长、主翼羽长，尾羽长，胫长和胫围对体重的相关，结果表明，公鸡早期生长速率较母鸡快，平均日增重比母鸡高０．９３ｇ，公母鸡６周龄体重 ３７５．０３ｇ和３３６．７７ｇ；     

杜泊肉用绵羊的种质特性

驰名全球的优秀肉用绵羊品种——杜泊羊，1960～1968年育成于南非共和国。它是目前世界最好的肉用绵羊品种和生产肥羔肉的理想终端父本，其肉质誉满全球，很受欢迎。我国自2002年以来，先后由南非和澳大利亚引入，信德种羊场也是我国首家引入杜泊羊的种羊场。     

日粮中复合添加剂水平与肉仔鸡生产性能关系的研究

以 1日龄、健壮的爱维茵肉仔鸡 6 30只 (公母各半 )为试验动物 ,应用肉鸡用复合维生素、复合微量元素和复合生物活性物质添加剂为试验因素 ,采用 3因子 5水平 2次通用旋转组合设计 ,平分成 2 0个组 (其中设 1个对照组 ) ,得到 15种施用水平组合及其 15种试验日粮 ,进行 7周龄饲养试验。结果表明 ,采食 15号日粮第 15～ 2 0组试鸡 ,7周龄增重最高达 2 36 8g ,料肉比最低达1.78,极显著地优于增重和料肉比均最低的对照组 17.5 2 %和 10 .10 % (P <0 .0 1) ;试验条件下 ,肉鸡增重、料肉比与 3种复合添加剂的施用水平有密切的相关关系 ,回归分析得出它们在日粮中最佳添加水平是复合维生素为 15 32 .0 7mg/kg、复合微量元素为 3796 .92mg/kg和复合生物活性物质为16 2 3.32mg/kg。     

日粮中添加柑桔皮粉对黄杂肉用仔鸡生产性能的影响

将32日龄黄杂肉用仔鸡240只随机分成4组,每组60只雏鸡。第1组为对照组,第2～4组为试验组,分别饲喂在基础日粮的基础上添加了3．5％,3．0％,2．5％柑桔皮粉的日粮,试验期35天。结果表明,在日粮中添加3．5％的柑桔皮粉组鸡效果最佳,料重比3．09-1,比对照组鸡降低11．71个百分点,饲料转化率提高了13．27％,只均增重0．9345kg比对照组鸡（0．8365kg）提高11．72％（P〈0．05）。经济效益比对照组鸡提高27．35％,增重耗料成本降低了0．55元／kg。     

Starch digestion rates in multiple samples of commonly used feed grains in diets for broiler chickens

In this study the starch digestion rates in broiler chickens from 18 samples of 5 commonly used feed grains (sorghum, wheat, maize, barley, triticale) were determined. The methodology to determine starch digestion rates in poultry is detailed herein. Starch digestion rates were not significantly different (P = 0.128) across the 18 feed grains, which reflects the wide variations that were observed within a given feedstuff. Nevertheless, starch digestion rates in broiler chickens offered wheat-based diets were significantly more rapid by 56.0% (0.117 versus 0.075 min⁻¹; P = 0.012) than their sorghum-based counterparts on the basis of a pair-wise comparison. In descending order, the following starch digestion rates were observed: wheat (0.117 min⁻¹), barley (0.104 min⁻¹), triticale (0.093 min⁻¹), maize (0.086 min⁻¹), sorghum (0.075 min⁻¹). The implications of these findings are discussed as they almost certainly have implications for poultry nutrition and the development of reduced crude protein diets for broiler chickens.     

The effect of dietary turmeric on antioxidant properties of thigh meat in broiler chickens after slaughter

Two hundred and fifty‐day‐old male broiler chicks (Ross 308) were used to investigate the dietary supplementation effects of different levels of 0.0 turmeric rhizome powder (TRP) (free TRP, F.TRP), 0.25 (low TRP, L.TRP), 0.5 (medium TRP, M.TRP) and 0.75% TRP (high TRP, H.TRP) or 50 mg/kg vitamin E (VE) on antioxidant properties of thigh meat in broiler chickens after slaughter. No effect of treatment was observed for the activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD) and total antioxidant status (TAS) in thigh meat (P > 0.05) but all were reduced over time (P < 0.0001). A significant treatment*time interaction was observed for thigh meat GPX activity (P = 0.02). Significant effects of treatment and time were observed for malondialdehyde (MDA) content (P < 0.05). There was no significant difference between the treatments for thigh meat MDA content at slaughter (P > 0.05). Three days after refrigerator storage, MDA content in thigh meat of M.TRP birds was lower than that of F.TRP birds (P < 0.05). Both the M.TRP and VE birds showed a lower MDA content in thigh meat as compared with F.TRP birds 7 days after storage (P < 0.05). In conclusion, dietary consumption of 5 mg/kg TRP can increases the thigh meat shelf‐life storage and quality in broiler chickens after slaughter.     

Effect of dietary astaxanthin rich yeast,Phaffia rhodozyma,on meat quality of broiler chickens

We evaluated effects of dietary supplementation with astaxanthin (Ax)‐rich yeast, Phaffia rhodozyma (Xanthophyllomyces dendrorhous), on broiler chicken meat quality. Fourteen‐day‐old female Ross broilers were divided into three groups: control group, Ax‐free diet; Ax 10 group, 10 mg/kg Ax diet; and Ax 20 group, 20 mg/kg Ax diet for 28 days. At 42 days old, chickens were slaughtered, and then growth performance, meat quality and sensory attributes were analyzed. Compared with the control, a* values increased significantly after slaughter and 48 h postmortem for Ax 20 samples (P < 0.05) and for b* values in Ax 20 and Ax 10 groups (P < 0.05). Cooking loss decreased in the Ax 20 group (P < 0.05). After 120 h aging, contents of several free amino acids and total free amino acid content of Ax 20 group were significantly higher than the control (P < 0.05). In sensory evaluation, meat texture attributes improved significantly in the Ax 20 group (P < 0.01). No significant changes occurred in flavor attribute scores of meat soup from the Ax 20 group compared with the control even though most assessors preferred meat soup from the Ax 20 group. Overall, Ax‐rich yeast in the diet improves broiler chicken meat quality.     

Body composition and heat expenditure in broiler chickens fed diets with or without trans fatty acids

The effect of a diet containing trans fatty acids (TFA) on the fatty acid composition and fat accumulation was investigated in broiler chickens. Female broilers were fed a control or a TFA-containing diet. The difference between the diets was that a part of cis 18:1 in the control diet was replaced by the TFA. Body composition, energy balance and the fatty acid composition were examined. Over the time-period studied (15 days), the body fat content and the protein content did not differ significantly between the TFA-fed group and the control. In energy balance studies, total energy intake, energy loss in excreta, energy expenditure and energy storage did not differ between the treatments. Compared to the control diet, the TFA diet resulted in significantly higher amounts of 14:0 and 18:1n-7 and lower amounts of 18:1n-9 and 20:4n-6 in the body. In conclusion, the data suggest that feeding TFA for 15 days to female broilers had no effect on energy retention, energy expenditure and energy loss in excreta or in body composition in terms of fat and protein. Only the fatty acid composition in the body was affected by the treatment with TFA. In addition, 50% of ingested TFA was incorporated into the body fat. This may have a negative effect on the dietetic value of chicken meat.     

肉鸡低血糖-尖峰死亡综合征调查研究

本研究对发生在华北地区的新型高致死性肉鸡疾病进行调查研究。发病主要集中在 8～ 18日龄 ,11～ 16日龄出现死亡尖峰。病鸡的血糖 (89.8± 7.9mg/dl)极显著低于正常鸡 (2 2 0 .3± 18.7mg/dl) (P<0 .0 1)。日死亡率高达 4 %～ 8%。典型症状表现为发病突然、头部震颤、运动失调、瘫痪、昏迷死亡。剖检可见肝脏弥漫性坏死 ,胰腺萎缩 ,十二指肠出血 ,胸腺、法氏囊、脾脏和盲肠扁桃体等免疫器官萎缩。泄殖腔聚集大量白色米汤样稀便。显微观察可见肝细胞坏死、淋巴滤泡排空、淋巴细胞坏死。依据国际诊断肉鸡低血糖 -尖峰死亡综合征 (HSMS)的标准 ,在国内首次确定我国有 HSMS发生 ,且在华北地区分布广泛 ,死亡率远高于国外报道的大于 0 .5 % ,而是高达 4 %～ 8%。已经成为危害肉仔鸡的重要疾病。采用控制光照和饮水中添加葡萄糖及多维等措施对 HSMS具有一定缓解作用     

Effect of dietary lysine to crude protein ratio on performance of male Ross 308 broiler chickens

Two experiments were conducted to determine the effect of dietary lysine to crude protein ratio on performance of male Ross 308 broiler chickens. In each experiment the diets were isocaloric and isonitrogenous but with different lysine to crude protein ratios. A complete randomized design was used in both experiments, the starter (1–21 days) and grower (22–42 days) experiments. The three starter diets, based on lysine to crude protein ratios, were L₀ (0.055), L₁ (0.066) and L₂ (0.077), while grower diets were L₃(0.047), L₄(0.061) and L₅(0.074). A quadratic type equation was used to determine ratios for optimum growth rate, feed conversion ratio, breast meat yield and breast meat nitrogen content. Dietary lysine to crude protein ratios of 0.066 and 0.077 supported optimum growth rate and feed conversion ratio, respectively, during the starter period. Dietary lysine to crude protein ratios of 0.073, 0.073, 0.069 and 0.079 supported optimum growth rate, feed conversion and breast meat yield and nitrogen content during the grower phase. Dietary lysine to crude protein ratio had no effect on diet intake and digestibility. The results indicate that at each phase a single dietary lysine to crude protein optimized both growth rate and feed conversion ratio. However, the ratio for optimum breast meat yield was lower than that for optimum growth rate and feed conversion ratio. These findings have implications on ration formulation for broiler chickens.     

The effect of bone choice on quantification of mineralization in broiler chickens up to 6 weeks of age

An experiment was conducted to assess the most appropriate bone type for measuring bone mineralization in male broiler chicks up to 42 d. A total of 72 male broilers were raised in 0.64 m² pens on a litter floor. The study design included 2 dietary treatments (Control and Low) containing differing levels of total phosphorus (7.8 and 4.4 g/kg for Control and Low diets respectively) and calcium (22.7 and 13.1 g/kg for Control and Low diets respectively) with each fed to 6 replicate pens of 6 birds. Each wk, 6 birds per diet were euthanized and leg bones removed to measure ash percentage. Foot, toe, tibia, and femur ash were compared using the mean of both legs from each bird, via t-tests to separate Control and Low diets. At the end of wk 1, diets could not be separated using any of the bone ash measures. From wk 2 to wk 5, both tibia and foot ash differentiated between the Control and Low diets, and tibia continued to show significant differences between the diets into wk 6. Femur ash did not show any dietary differences until wk 3, but then showed significant differences between the diets until wk 6. Toe ash only differentiated between diets at wk 2, and variation both within and between birds was high, particularly with younger birds. These results suggest that bird age has implications when choosing a bone for assessing possible differences in dietary phosphorus and calcium uptake. Femur ash may be more appropriate for showing differences in broilers aged 6 wk and older. Foot ash provides a comparable alternative to tibia ash in birds aged 2 to 5 wk of age, providing a labor- and time-saving alternative.     

五味子提取物对高脂系肉仔鸡肉质的影响

选用1日龄体重均一的健康高脂系肉仔鸡168羽,随机分为2组(对照组和0.125%五味子提取物组),每组6个重复,每个重复14羽.试验周期为56 d.结果表明:(1)五味子提取物对高脂系肉仔鸡的胸肌和腿肌水分、蛋白质及胸肌脂肪含量无显著影响(P>0.05),但显著提高腿肌的脂肪含量(P<0.05);(2)五味子提取物显著提高高脂系肉仔鸡胸肌的肌纤维密度,显著降低腿肌的肌纤维直径(P<0.05),对胸肌肌纤维直径、腿肌肌纤维密度无显著影响(P>0.05).(3)五味子提取物显著降低高脂系内仔鸡胸肌、腿肌剪切力(P<0.05).