Identifying the social dominance order in a mixed breed herd: A practical methodology

• Antonio Landaeta Hernández Universidad del Zulia-Venezuela
• Peter Chenoweth Kansas State University-Estados Unidos
• Ronald Randles University of Florida-Estados Unidos
• Ramon Littell University of Florida-Estados Unidos
• Owen Rae University of Florida-Estados Unidos
• Chad Chase Unite State Department of Agriculture-Estados Unidos

Palabras clave: cattle, behavior, social organization

Resumen

The major objective of this study was to identify a simple and accurate method of assessing differences in female social status. Three methods of estimating dominance value (DV) were compared in beef cows of three breed-types; Angus (A; n=10), Brahman (B; n=10), and Senepol (S; n=10). Cows were equitably assigned to two groups of fifteen each, allocated into separate pastures and containing equal number of animals by breed. Agonistic interactions were recorded for 45 d of study, in two 1 h periods during concentrate feeding using the method of competitive orders winner/loser. Methods of estimating DV included: I) Ratio between individuals dominated and total encountered, II) Ratio between encounters won to total encounters, III) Proportion of individuals dominated to total herdmates. Due to the different level of interactivity evidenced among animals as well as between and within social orders, method III with subsequent arc-sin transformation was considered as the most practical and accurate method for estimating DV and subsequent allocation of cows into a social dominance order. In addition, a breed effect was found on social dominance. Senepol cows obtained greater DV´s (1.24 Ó 0.08) than Angus (0.97 Ó 0.08; P < 0.03) and Brahman cows (0.76 Ó 0.08; P < 0.005).