Performance and meat carcass characteristics of locally slaughtered sheep and goats raised by grazing native tropical grasses with or without supplementation

Abstract

This study was divided into two parts. In the first part, data were collected from 57 sheep and 28 goats from different origins and slaughtered in abattoirs in the western region of Puerto Rico to develop a database of the carcass characteristics of small ruminant (SR) raised under traditional feeding management. The second part consisted of a feeding trial in which weaned lambs (n = 6) and kids (n = 6) were randomly assigned within species to one of two feeding regimes: with or without daily commercial concentrate (CC) supplementation, at the rate of 0.9% of body weight (B W) on a dry basis, to grazing native tropical grasses. Treatment effects on body weight gain, carcass characteristics, and meat quality were evaluated. The database on carcass characteristics of SR slaughtered commercially showed highly variable dressing percentages ranging from 37 to 46%, and 32 to 38% for sheep and goat, respectively, both species having similar (P > 0.05) average values. No differences were observed in dressing percentages between the sexes. Supplementation with CC increased (P < 0.05) total and daily BW gain in lambs by 2,580 and 40 g, respectively, when compared to the non-supplemented controls. In kid-goats, BW gains with supplementation were appreciably, but not significantly greater (P > 0.05) than without supplementation. Dressing percentage, and fore and hind trunk percentages did not vary (P > 0.05) between treatments for either species. There were no differences (P > 0.05) in pH, moisture, crude protein, and fat percentages of longissimus muscle between treatments in either species. This research revealed the need to develop a local grading system to standardize the meat and improve its quality. Similarly, genetic selection of animals as well as research on alternative less-expensive feed resources for finishing meattype animals are necessary to improve quantity and quality of local small ruminant meat (SRM).