提高晋南牛肉用性能的杂交组合研究（二报）：杂交一代与晋南牛肥育性能测定

平均15月龄的夏晋、西晋、利晋杂交1代和晋南阉牛各4头，按美国NRC肉牛营养标准配合日粮，经100天育肥后屠宰（约18月龄）测定其肉用性能。复晋、西晋、利晋和晋南牛平均日增重分别是904．5±9．12，838．5±6.2，824．3±3．29和618．7±16．6克；每增重1千克活重消耗总可消化养分6．11，7.01，7.15和7.83千克；消耗粗蛋白质846．7，931．1，949．1和1047.9克；宰前活重分别为421．5±7.94，412，0±7．53，404.3±10．52和318．0±11．63千克；屠宰率平均分别为57．5．56．96，55．97和51．69％；肉骨比分别为4．65，4．35．5．12和4．1；体腔脂肪总重分别为15．85，11．15，11．70和17.35千克。结果表明，杂交牛肉用性能均有较大提高。     

草原红牛导入丹麦红牛血液试验效果(第二报)

为了提高草原红牛的生产性能,1985年开始在翁牛特旗海金山种牛场进行了草原红牛导入丹麦红牛血液试验。初步试验结果表明:丹红F_1毛色基本同草原红牛;尻部宽、长而平,原有斜尻缺点已明显得到改进;各阶段体重、体尺均有明显提高,尤以体躯的重量、宽度、高度和后躯的提高更为显著;适应性与草原红牛无差别;其产肉性能和产奶性能比草原红牛亦有明显提高。     

Dose response of rumen‐protected conjugated linoleic acid supplementation to fattening bulls and heifers on growth,and carcass and meat quality

We investigated the influence of rumen‐protected conjugated linoleic acid (rpCLA) on growth performances, and carcass and meat quality traits in beef. Twenty‐four young bulls and 30 heifers obtained from double‐muscled beef sires and dairy cows were fed a low‐protein ration (110 g/kg DM of crude protein) supplemented with 0, 8 or 80 g/d of a commercial rpCLA product. The animals were monthly weighed and scored for body muscularity and fatness. Blood samples were collected after 140 days on feed. Animals were slaughtered when they reached average in vivo fatness scores of around 2.5 (heifers) and 2.0 (bulls) points respectively. At slaughter, carcasses, various organs and parts of the gastrointestinal tract were weighed; the 5th rib was dissected and its tissue and muscle chemical composition was determined. The rpCLA had little influence on growth performance but decreased the blood urea content by 28% (p < 0.01). The rpCLA × sex interactions for daily gain (p < 0.05), conformation scores (p < 0.01), and blood creatinine content (p < 0.05) suggest that males were more responsive to rpCLA than females when fed a low‐protein ration, probably because of the metabolic protein‐sparing effect of CLA. Only slight differences were observed in carcass weight and quality at slaughter. The results indicate that the response of beef cattle to rpCLA is dependent on sex or on their propensity for lean and fat accretion. It is also possible that counteracting feedback mechanisms compensate for the influence of rpCLA administration over the course of growth.     

西杂肉牛球虫病的诊断与虫种鉴定

[目的]为肉牛球虫病的诊断和防治提供依据。[方法]通过对新乡市某肉牛场患出血性肠炎的西杂肉牛进行临床检查,粪便直接涂片检查和饱和食盐水漂浮检查,并对粪样中分离的球虫卵囊及其孢子化卵囊进行形态学观察和虫种鉴定。[结果]在粪便中检出大量球虫卵囊,球虫经鉴定分别为艾美耳属的牛艾美耳球虫、邱氏艾美耳球虫、巴西艾美耳球虫、巴克朗艾美耳球虫和椭圆艾美耳球虫,确诊该牛场的出血性肠炎是由多种牛球虫混合感染引起的牛球虫病,其中,牛艾美耳球虫和邱氏艾美耳球虫为该肉牛场的优势种。[结论]临床检查、粪便实验室检查和虫种鉴定是诊断肉牛球虫病的一套简便实用方法。     

夏南横交牛犊牛补饲试验研究报告

本试验针对夏南横交牛犊生长发育特点,采取提前补饲精料的办法,研究适时补饲对其日增重、断奶重的影响,探索提高其断奶体重的方法。从存栏的初生牛犊中,随机选择了37头夏南横交牛,分为试验组30头,对照组7头,试验期180d,试验结果：试验组平均初生重41．43kg,平均目增重0．88kg,6月龄时平均体重达199．57kg(实称重);对照组平均初生重42kg,平均日增重0．73kg,6月龄时平均体重达173．43kg。试验组与对照组平均日增重经t检验差异极显著。     

丹麦红牛改良我县秦川牛效果初报

陕西省富平县是全国著名的奶山羊基地县,近年由于商品经济的迅速发展,奶山羊产奶量低,经济效益不高,已远远不能满足农村家庭经济发展的要求,因而出现奶山羊大幅度“滑坡”现象,以致鲜奶供不应求,乳品加工厂奶源严重不足。为了解决奶源问题,富平县于1987年开始用丹麦红牛改良秦川牛,二年来共配2367头,产犊670头。丹秦F_1体型外貌与秦川牛相比,背腰宽广,后躯宽平,乳房大,毛色多呈紫红或红色;其初生重平均为29.69kg,比秦川牛提高49.20％,30、90、180、360日龄体重分别提高43.9、30.6、4.5和23.0％;F_1牛耐粗饲,适应性强,能耐寒、耐热,深受当地群众喜爱。     

不同果胶含量的饲粮对羔羊瘤胃内环境的影响

选用32只3~3.5月龄的波德代(♂)×蒙古羊(♀)和陶赛特(♂)×蒙古羊(♀)的杂交一代羔羊,采用2×2×2三因子设计,研究了两个营养水平下(高,0.9 NRC;低,0.8 NRC),两种果胶含量的全混合饲粮(高果胶组:甜菜渣组;低果胶组:小麦组)对两种杂交组合的羔羊瘤胃液pH值、总氮、氨氮、尿素氮和蛋白氮含量的影响。试验表明:羔羊的瘤胃液pH值和瘤胃液尿素氮含量在两营养水平间差异显著,低营养水平组的瘤胃液pH值(P=0.024)和瘤胃液尿素氮(P=0.024)显著较高;营养水平与果胶含量的互作显著影响瘤胃液pH值,其中0.9NRC水平下低果胶较高,0.8 NRC水平下高果胶组较高;杂交组合对所有测定指标均无显著影响。结果说明,果胶对饲喂高淀粉饲粮动物的瘤胃液pH值的调控作用与果胶及淀粉间的数量关系有关。     

西杂肉牛屠宰试验报告

对3头15～18月龄的西杂牛和2头24月龄的本地黄牛进行屠宰试验。西杂牛平均屠宰率56．7％,净肉率47．8％;当地黄牛屠宰率与净肉率分别为50．1%和39．1％,西杂组比黄牛组分别高6．6％和8．7%。     

皮埃蒙特肉牛三元杂交研究

用皮埃蒙特牛的冷冻精液进行人工授精,改良西门塔尔杂种母牛和晋南母牛,杂交试验,以期为皮埃蒙特肉牛杂交改良利用、提高高档牛肉的生产,提供科学的数据。试验结果表明,皮埃蒙特三元杂种公犊牛初生重、6月龄重、18月龄重分别是36.2 kg、182.3 kg和542.2 kg,育肥期12～18月龄平均日增重1079 g。屠宰率为61.4%,净肉率为52.3%,眼肌面积102 cm2。皮晋牛屠宰率为59%,净肉率50.4%,眼肌面积84 cm2。育肥屠宰试验结果表明,皮西杂组合杂交改良效果明显。