Body dimension comparisons between slick and wild type-haired Puerto Rican Holsteins

Abstract

A previous study from our group evaluating growth in dairy heifers suggests that Puerto Rican Holstein slick-haired heifers (SLICK) could reach maturity earlier and at smaller body size than their wild type-haired (WT) counterparts. Thus, the present study aimed to determine if such differences exist in mature cows by comparing several body dimensions (i.e., body weight, withers height, hip height, thoracic perimeter, barrel, and shoulder to pin bone distance) of 24 SLICK and 54 WT lactating Holstein cows at the Agricultural Experiment Station in Lajas, Puerto Rico. Also, body weight was divided by each dimension to obtain the respective ratios. Data were analyzed by the GLIMMIX procedure of SAS. The SLICK cows presented larger barrels (236.54±2.68 vs. 231.06±2.29 cm; P=0.0363) and body weight / shoulder to pin bone distance (3.51±0.09 vs. 3.32±0.08 kg/cm; P=0.0218) than their WT counterparts. However, the shoulder to pin bone distance was smaller in SLICK than in WT cows (180.07±1.82 vs. 185.20±1.56 cm; P=0.0059). No significant differences between hair coat groups were observed in any other evaluated variable. The SLICK cows had shorter and deeper bodies than WT cows. Future studies should evaluate if such differences could impact their productive efficiencies.