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In this study, random amplified polymorphic DNA (RAPD) analysis was used to estimate genetic diversity and relationship in 134 samples belonging to two native cattle breeds from the Yunnan province of China (DeHong cattle and DiQing cattle) and four introduced beef cattle breeds (Brahman, Simmental, MurryGrey, and ShortHorn). Ten primers were used, and a total of 84 bands were scored, of which 63 bands (75.0%) were polymorphic. The genetic distance matrix was obtained by proportions of shared fragment. The results indicate that the Yunnnan DeHong cattle breed is closely related to the Brahman (Bos indicus), and the Yunnan DiQing cattle breed is closely related to the Simmental, ShortHorn, and MurryGrey (Bos taurus) breeds. Our results imply that Bos indicus and Bos taurus were the two main origins of Yunnan native cattle. The results also provide the basic genetic materials for conservation of cattle resources and crossbreeding of beef cattle breeds in South China.

There are seven species in the genus Bos: B. taurus, B. indicus, B. banteng, B. Bison, B. grunniens, B. gaurus and B. frontalis. The relationships among the species (except B. frontalis) have been investigated based on morphological characteristics (Bohlken, 1958, 1961), cranial characteristics (Groves, 1981), mitochondrial DNA data (Miyamoto et al., 1989; Loftus et al., 1994; Bradley et al., 1996; Yu et al., 1999), and ribosomal DNA restriction site data (Wall et al., 1992). B. frontalis originated from India, Burma, and Yunnan Province of China. As far as we know, the genetic relationship between B. frontalis and the other Bos species has not been reported. In our previous studies, we reported 44 blood protein loci polymorphism of 30 mithun samples (Nie et al., 1999) and 34 blood protein loci polymorphism of 177 yaks (Tu et al., 1997). In this study, we investigate the genetic differences of blood protein loci among the 4 Bos species under the same electrophoresis condition and these shed light on the evolutionary position of B. frontalis.

Genetic variation of 31 blood protein loci in 236 cattle from eight South China populations (including mithan, Bos frontalis) and a Holstein population was investigated by means of horizontal starch gel electrophoresis. Thirteen loci (ALB, CAR, Hb-b, Np, PGM, Amy-I, PEP-B, AKP, 6PGD, Cp, Pa, EsD, and TF) were found to be polymorphic. The comparison of average heterozygosities (H) shows that all the native cattle embrace a rich genetic diversity. Our results on protein polymorphism suggest that cattle in China originated mainly from Bos indicus and Bos taurus; Xuwen, Hainan, Wenshan, and Dehong cattle and the Dehong zebu are close to zebu-type cattle, and Diqing and Zhaotong cattle are close to the taurine. The mithan was very different from other native cattle, and we suggest that its origin was complicated and may be influenced by other cattle species.