Michelle Gonçalves

Influência da castração e da idade de abate sobre as características subjetivas e instrumentais da carne de cordeiros Corriedale

The objective of this trial was to evaluate the effects of castration and slaughtering age on subjective and instrumental characteristics of meat from Corriedale lambs raised on native pasture. Sixty male lambs (30 castrated and 30 intact) slaughtered at 120, 210 and 360 days of age were used in this experiment. The Longissimus dorsi muscle was used for all meat evaluations and analysis. No significant castration ´ slaughtering age interaction was observed for the studied variables. A significant slaughtering age effect was found for meat fat thickness and marbling, which had lower scores in animals slaughtered at more advanced age as well as for all instrumental characteristics of the meat, mainly tenderness that was reduced in older lambs. However, a significant castration effect was observed only for meat color (brightness according to the CIELAB system). It can be concluded that meat quality from Corriedale lambs grazing native pasture was not affected by castration. Slaughtering age affected meat quality with lambs slaughtered at 120 days of age showing the best results.

Época de nascimento sobre a composição regional e tecidual da carcaça de cordeiros da raça Texel

The effect of alternative birth season on regional and tissue carcass composition of sheep was evaluated. Forty nine (49) Texel intact male lambs, born in two seasons (August and November), were kept under grazing and slaughtered with an average age of 129 and 164 days, respectively. Prior to slaughter forage production was measured using Botanal method. Lambs born in August had more favorable forage conditions, showing higher body weight and proportion in the majority of cuts, as well as lower proportion of shoulder and leg muscles showing higher adipose tissue content in the majority of carcass cuts. For lambs born in November, a higher muscle:fat and muscle:bone rate in shoulder and leg, as well as a higher ribcut muscle:fat rate. Nutritional conditions are responsible for differences in weights and cuts yields, as well as for the tissue carcass composition, in lambs maintained under grazing regime, making feasible the use of alternative birth periods to increase animal offer for slaughter.