Zoometric indices in Creole cattle of Patagonian and northwestern Argentine origin

Abstract

All the Argentine Creole bovine has a common origin, but due to the undergone historical process, there can establish two populations well differentiated from the geographical point of view: the Creole of the Argentine Northwest (N) and the Patagonian Creole (P). The prolonged exhibition to environmental effects differentials, the natural selection and the reproductive isolation within each group, could originate genetic and/or phenotipic differences between the groups. There are described the bovine Creoles of both regions and of both sexes: Patagonian Male (PM); Patagonian Females (PH); North Male (N M) and North Females (NH), by means of five zoometric indexes: Cephalic Index (ICEF = AC/LC); Lateral Corporal Index (ICL = ACR/LT); Corporal Index (IC = LT/PT); Index of Anamorphosis (IA = PT2/ACR) and Pelvic Index (IPE= AAG/LG). The differences between groups determined by variance analysis and the approach of Tuckey-Kramer. Also the discriminant coordinates were obtained and four classes were represented in the plane defined by the first two coordinates. Significant sexual dimorphism in both populations was observed and a longitudinal phenotype in the PH and PM demonstrated by the IC and the IA. The first coordinate separates the groups by sex, whereas the second difference groups PM. and NM, but is inefficient to discriminate NH of PH.