Rishi S, Agarwal V K, Anand G R, Agarwal S P, Balaine D S, Dwaraknath P K
Biochem Genet. 1981 Oct;19(9-10):987-96. doi: 10.1007/BF00504262.
Serum guanase levels of Indian Zebu (Hariana) cattle and its crosses with different exotic levels of temperate breeds of dairy cattle were estimated in 527 animals, and their associations with economic characters were determined. The overall mean value of serum guanase level was 13.46 +/- 0.45 IU/ml of serum. An inverse relationship between the concentration of the enzyme and the frequency of cattle falling within a definite range was observed, as over 75% of the animals possessed 1 to 20 IU/ml of serum guanase. An analysis of variance revealed significant differences (P less than 0.01) in enzyme levels among different genetic groups under study. Hariana (Zebu) purebreds had significantly higher enzyme levels (19.60 +/- 1.85) than any of the crossbred groups, whose enzyme levels ranged from 8.99 +/- 1.41 in Red Dane F1 half-breds to 14.30 +/- 1.11 in Brown Swiss F1 half-breds. The correlation and regression coefficients were significantly positive for reproductive traits such as age at first service and age at first calving, and significantly negative for production traits such as lactation yield and lactation length. These results suggest that selection of dairy cattle based on low serum guanase levels might result in correlated improvements in dairy cattle productivity.
在527头动物中，对印度瘤牛（哈里亚纳牛）及其与不同外来温带奶牛品种杂交后代的血清鸟苷酶水平进行了测定，并确定了它们与经济性状的关联。血清鸟苷酶水平的总体平均值为13.46±0.45 IU/ml血清。观察到酶浓度与处于特定范围内的牛的频率之间呈负相关，因为超过75%的动物血清鸟苷酶水平为1至20 IU/ml。方差分析显示，所研究的不同遗传群体之间的酶水平存在显著差异（P<0.01）。哈里亚纳（瘤牛）纯种牛的酶水平（19.60±1.85）显著高于任何杂交群体，杂交群体的酶水平从红丹麦F1杂种的8.99±1.41到瑞士褐牛F1杂种的14.30±1.11不等。对于首次配种年龄和首次产犊年龄等繁殖性状，相关系数和回归系数显著为正；对于泌乳量和泌乳期等生产性状，相关系数和回归系数显著为负。这些结果表明，基于低血清鸟苷酶水平选择奶牛可能会使奶牛生产力得到相关提高。
