摘要
大额牛是中国唯一的半野生半家养的珍珍稀牛种,仅分布于云南省的独龙江和怒江流域,以及印度的阿萨姆邦、东孟加拉和与缅甸北部钦邦。根据国内外研究和多年调查认为:(1)大额牛(Bosfrontalis)染色体的数目、形态、结构均不同于黄牛(Bostaurus)和野牛(Bosgaurus),3者染色体数目(2n)分别为58,60和56条,在常染色体中黄牛没有近中着丝点染色体,野牛有两对,而大额牛有一对,染色体的臂数相等;(2)大额牛的食物以竹子、青蒿和杂草为主,饲料条件差,生存环境恶劣,但其生长速度快,0 5,1,1 5,2和3岁大额牛的体重可分别达140kg,218kg,264kg,296kg和342kg;(3)大额牛具有较为典型的肉用牛体型和较好的产肉性能,且其肌纤维直径明显小于其它牛,牛肉的系水率、嫩度和多汁性明显高于其它牛;(4)繁殖力强,能繁母牛基本上可实现一年一胎,且可以与黄牛杂交。大额牛不仅具有极高的研究学术价值,而且有极大的开发利用价值。
The gayal (Bos frontalis) belonged to the only semi-wild and semi-domestic cattle that distributed in the Dulong River and Lujiang River region and Assam state of Indian, northern of Bangladesh, and some hilly area of Myanmar and Bhutan. According to the past research and investigation, the results showed that: (1) The amounts, shape and structure of chromosome of gayal (Bos frontalis) weren't same to the yellow cattle (Bos taurus) and wild cattle (Bos gaurus), whose amounts of chromosome (2n) were 58, 60 and 56, respectively. There were two pairs of acrocentric chromosomes for wild cattle, one for gayal but not for yellow cattle. The amounts of arms were same among three kinds of cattle. (2) The environment that gayal lived was so poor that the diets mainly were bamboo, southernwood and weed grass, however, the rate of growth was so quickly that live weight was 140, 218, 264, 296 and 342 kg when the ages was 0.5,1, 1.5, 2 and 3 years, respectively. (3)The gayal also had typical bodily form and very good meat performance, which diameter of muscle fiber was less than others kinds of cattle. The water holding ratio, the muscle tenderness and muscle succulency were higher than others kinds of cattle significantly. (4) The reproductivity was so strong that the female gayal could produce one calf per one year and also could produce profitable hybrid offspring crossing gayal bulls with yellow cattle and cows. As a result, there were not only very high applied values in academic aspects but also in exploitation and utilization.
出处
《云南农业大学学报》
CAS
CSCD
2005年第2期258-261,共4页
Journal of Yunnan Agricultural University
关键词
大额牛
染色体
生长
繁殖
肉质
杂交
Gayal (Bos frontalis)
chromosome
growth
reproductivity
meat quality
hybridize
