Abstract
The social rank refers to the relative position of an individual animal within the dominant hierarchy developed in a group. In rams, social rank is mostly associated with body mass, body size and body condition. However, although the body mass is generally considered as one of the main determinants of social rank, only few studies have been carried out for the purpose of associating of the social behavior and body development of these animals. Objective of this research was to determine how the ram body development measures relate to establishment of social hierarchy. Social rank was established using food competition test at the age of animals between 4 and 17 months. Testing was done on total of 20 male animals of which number 12 animals were selected for further testing (6 dominant and 6 submissive animals). Body mass and testicular circumferences were measured at the age of 4, 7, 12 and 18 months, and linear body measures were taken at the age of 12 and 18 months. Dominant males had higher body mass and greater testicular circumference. The social rank had no significant effect on linear body measures of rams, except for chest girth (P<0.05) in both control periods. Body mass was moderately to highly positively associated with studied body parameters. Significant positive correlations were established between body mass and body length (r=0.58; P<0.01), chest width (r=0.44; P<0.05), chest girth (r=0.65; P<0.01) and testicular circumference (r=0.62; P<0.01). Results obtained in this study indicate that it is justified to observe the body mass as one of the main determinants of social rank, as well as the possibility of earlier maturation of dominant animals.
Highlights
In ruminants, social hierarchies are mainly associated with unequal access to various sources such as food, water, space, shade or to female animals
Social rank can be defined as relative position of an individual animal within a dominant hierarchy formed in a group (Pelletier and Festa-Bianchet, 2006)
Significant effect of social rank on testicular circumference was established at the age of 7 and 12 months (P
Summary
Social hierarchies are mainly associated with unequal access to various sources such as food, water, space, shade or to female animals. High social rank is achieved by teasing of other animals in the group, in so called dominance fights (Drews, 1993), and individual characteristics which mostly contribute to the competitive advantage during these fights are size of body and horns (Coltman et al.,2002; Preston et al.,2003). Social rank is mainly associated with body mass (Pelletier and FestaBianchet, 2006; Ungerfeld and Gonsalez-Pensado, 2008), size of horns, body size and body condition of rams (Preston et al, 2003). These authors have observed that dominant rams have greater testicular circumference and realize higher copulation rate and eventually more lambs. Testosterone, steroid hormone produced in testicles, stimulates the development and growth of the skeleton and muscles, promotes secondary sex features and increases the aggressive behaviour - traits which can lead to increase of the competitive ability of rams (Sapolsky, 1993)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
