肺动脉高压肉鸡肺小动脉中膜5-HT量及其与肺血管重构的关系

静脉注射纤维素粒子复制肉鸡肺动脉高压模型,观察肺小动脉中膜5-羟色胺(5-HT)表达和肺小动脉管壁病理形态学变化,探讨5-HT与肺血管重构的关系。80羽科宝肉鸡分为对照组(n=30)和试验组(n=50)。20日龄时,试验组每羽鸡静脉注射0.3 mL的纤维素悬液;对照组每羽鸡静脉注射等体积生理盐水。记录肺动脉高压综合征(PHS)发病率,并分别于21、28、35、42 d从各组随机抽样,测定右心室/全心室质量比(RV/TV)、红细胞压积(PCV)、血红蛋白(Hb)、肺小动脉管壁面积/管总面积(WA/TA)、平均中膜厚度(mMTPA)和肺厚壁末梢血管百分比(TWPV%);采用免疫组化方法标记5-HT,并用病理图像分析软件检测肺小动脉5-HT的量。结果表明:试验组肉鸡PHS发病率显著高于对照组(P<0.05);RV/TV值在35、42 d时显著升高(P<0.05);PCV在28、35 d时显著升高(P<0.05);Hb值在35 d时显著升高(P<0.05);血管mMTPA、WA/TA和TWPV%在35、42 d时均显著升高(P<0.05);肺小动脉5-HT含量升高,在各时间点均差异显著(P<0.05),且5-HT含量...     

关于肉种鸡代谢能的研究进展

本文主要就肉种鸡的代谢能水平及现状、能量限饲对肉种鸡的影响以及肉种鸡代谢能需要量的具体研究方法等几方面作一综述,为肉种鸡的营养研究提供参考。     

Welfare and environmental benefits of integrating commercially viable free-range broiler chickens into newly planted woodland: A UK case study

The commercial, welfare and environmental impacts of rearing small colonies of free-range chickens in newly planted woodland at two sites in the UK, during the first 2 years of the enterprise, were investigated. Newly planted rather than established trees were used so that commercially viable species could be planted in a way that would suit the management of the chicken enterprise, and small colonies were used so that farmers wishing to diversify could buy into the system progressively. It was anticipated that marketing a high specification product would provide an immediate income, whilst waiting for the future investment in trees to grow.     

The effect of selected microbial strains on internal milieu of broiler chickens after peroral administration

The aim of this work was to investigate the effect of probiotic preparation with multi-strains composition (Lactobacillus delbrueckii ssp. bulgaricus LAT 187, Lactobacillus acidophilus LAT 180, Lactobacillus helveticus LAT 179, Lactobacillus delbrueckii ssp. lactis LAT 182, Streptococcus thermophilus LAT 205 and Enterococcus faecium E 253) on internal milieu, antioxidant status and body weight of broiler chickens. Chickens were divided into three groups (C, control; E1 and E2, experimental groups). Experimental chickens received the probiotic preparation in drinking water. Probiotic preparation caused a significant increase of serum calcium and potassium content. In the group with higher dose of probiotic strains serum triglycerides level decreased. Total antioxidant status in groups with addition of probiotic strains showed higher values in comparison to control group. Serum albumin level was found to increase after consumption of probiotic preparation in group with higher dose of probiotic strains. Probiotic strains improved body weight in last observed weeks of feeding.     

泰和乌鸡配套系商品肉鸡的肉质特性研究

研究了泰和乌鸡配套系商品肉鸡的肉质特性。结果表明:通过改良育种后,泰和乌鸡配套系商品肉鸡不仅早期生长速度得到了较大的提高,而且与原种泰和乌鸡的肉质特性基本一致。     

肉种鸡营养传代效应的研究进展

该文综述了肉种鸡营养的传代效应,指出通过调整肉种鸡营养可以改善后代肉仔鸡品质,提高肉仔鸡免疫机能,进而影响其生长性能和胴体品质。     

持续日变高温对肉鸡矿物质代谢的影响

为研究持续日变高温环境对肉仔鸡矿物质代谢的影响,选用体重接近的20只肉仔鸡,随机分为两组,另选体重接近的4只肉仔鸡,施人工肛门手术。试验组持续日变高温环境设为25～35℃,其中每日35℃持续3h。对照组为20℃恒温。在人工气候舱内适应8d后,每只鸡收集3d尿和总排泄物,并对其中矿物质排出量进行测量,分别对试验前及试验结束时血液中矿物质浓度进行测量。结果表明:持续日变高温使肉仔鸡血清中K浓度显著下降,Zn浓度上升,其它矿物质元素浓度无显著变化,在限饲相同进食量情况下,热应激使K、P、Mg、Na和Co的排出量明显低于对照组,而其它矿物元素排出量与对照组无显著差异,尿中矿物质浓度无显著变化。     

间歇光照对肉仔鸡免疫器官和部分免疫指标的影响

[目的]探讨间歇光照对肉鸡免疫机能的影响。[方法]选取1日龄健康的240羽AA＋肉仔鸡,随机分为对照组（C）、光照1组（L1）和光照2组（L2）,于7～30 d期间对3个试验组分别采取24L∶0D、22L∶2D和20L∶4D的间歇光照措施,30 d后均恢复为连续光照,并于14、21、28、35、42 d观测各试验组肉仔鸡血液中免疫参数的变化,于14、28、35、42 d测定各组的免疫器官指数。[结果]在14～42 d观测期间,间歇光照L1和L2组可提高肉仔鸡的总蛋白和白蛋白水平及脾脏和法氏囊指数,但仅L2组的白蛋白于21和35 d极显著高于C组（P〈0.01）,其余各指标值与C组间均无显著差异（P〉0.05）。L1和L2组的球蛋白值和ND效价与C组间均无显著差异（P〉0.05）。[结论]采用22L∶2D和20L∶4D的间歇光照措施对肉仔鸡的免疫功能具有一定的促进作用。     

Fertilizer value of nitrogen in hen and broiler manure after application to spring barley using different application timing

The nitrogen (N) fertilizer effect of layer hen and broiler manure applied at different times on spring barley yield was studied in seven Swedish field experiments during 2005–2008. Two experiments had parallel field incubations to study N release after fertilizer application. The effect of total N in manure on N offtake was 30–40% that of mineral N, except in a dry year, when the effect was very low. Although the relative proportions of ammonium N, uric acid N and other N differed between the hen and broiler manure, the effect of total N was similar for both. In field incubations, mineral N decreased from 75 to 60% of total N applied in hen manure, whereas it increased from 20 to 50% in broiler manure, because of net immobilization and release, respectively. The limited fertilizer nitrogen replacement value, corresponding to only 30–40% of total N, could be as a result of ammonia volatilization after rather shallow incorporation with harrow. Net N release from broiler manure lasted for 6–8 weeks after application, after which it generally ceased. In some cases, manure application in early spring gave better yield effects than application at sowing, probably because of better synchronization of the N release with crop N requirements. The residual N effect on the N offtake in crop in the year after manure application was on average 3% of the total N applied, equivalent to a fertilizer replacement value of about 6%.