​In the Absence of Sexual Competition, Rams with Low Social Ranks Show more Appetitive Sexual Behaviors than Males with High Ranks

Abstract

Background: Usually, social order is defined by the animals´ size, live weight, or age. This study evaluated the effect of social rank and morphometric characteristics upon appetitive and consummatory sexual behaviors in Dorper rams in absence of sexual competition. Methods: The research took place in northern Mexico (26°N), 36 rams allocated into two groups were used: Low social rank (LR; n = 17) and high social rank (HR; n = 19). Behavior tests were performed for all the males, for which each one was placed in contact with a female in estrus. Result: There were no differences between ranks and morphometric characteristics (P less than 0.05). A correlation of 29% was found for the success index concerning odor in HR. Likewise, a relationship existed between the presence of horns (Pho) and all the other variables, but not between PHo vs success index (rho 0.07). Appetitive sexual behavior was the highest (P less than 0.05) for LR, while HR had more consummatory sexual behaviors (P less than 0.05). We conclude that sexual hierarchy exists even when the males have the same morphometric characteristics, nonetheless, males with low social ranks show more appetitive sexual behaviors while those with high ranks show a higher number of consummatory sexual behaviors when managed in intensive farming conditions.