Comparative studies on the evaluation of productive traits and its efficient use in buffaloes

众所周知，家水牛对热带湿热环境具有良好的适应性，比牛更能有效地利用粗饲料。本研究旨在通过与相同年龄、相同饲养条件下的牛进行比较，从1)体温调节反应、2)饲料利用和育肥性能、3)生殖性状等方面对水牛的生理和生产性状进行表征。研究结果表明：1)水牛的身体水分周转率比普通牛高，排汗散热能力和皮肤表面水分蒸发散热能力比普通牛低，而水牛的储热能力和敏感散热能力必然较高，这些特点使水牛具有较好的热环境耐受性。（参考文献1和2）2)水牛对干物质的消化率和饲料能量利用率均优于牛，如果在幼龄饲养和饲养得当，其产肉性能可达到肉牛的水平。（参考文献3,4和6）3)为了克服水牛超排卵和体外受精产生胚胎效率较低的问题，人们进行了将水牛体细胞核移植到牛卵母细胞的尝试。结果，成功地获得了胚泡期形态正常的胚，即属间核移植胚。（参考文献5）这些研究结果表明，在长期的进化过程中，家养水牛已经形成了适应湿热环境的独特的生理和生态特征，表明水牛是热带地区很有前途的肉类和奶源动物。

It has been known that domestic buffaloes have a good adaptability to hot-humid tropical environments and can utilize coarse fodder more efficiently than cattle. This study aimed at to characterize the physiological and productive traits of buffaloes in terms of 1) thermoregulatory responses, 2) feed utilization and fattening performance, and 3) reproductive traits, by comparing the traits to those of cattle with same ages and same feeding conditions. Research results obtained are as follows :1) Buffaloes show a higher body water turn over rate and lower heat dissipation ability by sweating and water evaporation from skin surface than in cattle, while the heat storage capacity and sensitive heat dissipation are inevitably high in buffaloes, and these characteristics allow the buffalo well-tolerate hot environments. (ref.1 and 2)2) Buffaloes show a superior digestibility of dry matter and more efficient feed energy utilization rates than cattle, and, if raised and fed properly at young ages, they show a good meat-producing performance as high as beef cattle. (ref.3, 4 and 6)3) To overcome less efficient yield for embryo production by super ovulation and in vitro fertilization in buffaloes, an attempt of nuclear transfer of buffalo somatic cells to cattle oocytes has been conducted. As a result, the morphologically normal embryos at blastocyst stage, a inter-generic nuclear-transferred embryo, were successfully obtained. (ref.5)4) These research results demonstrate that the domestic buffaloes have developed their unique physiological- and ecological traits through long-term evolutional period being well-adapted to hot and humid environments, and show that the buffalo is a promising animal in the tropics as a meat and milk producer.