Alexandre Agostinho Mexia

Desempenho de cordeiros alimentados com diferentes níveis protéicos

The experiment was carried out to evaluate increasing crude protein (CP) levels in drylot lambs diet, and its effects on animal performance. Thirty two tricross lambs (1/2 Texel + ¼ Bergamacia + ¼ Corriedale), being 16 males and 16 females, with average age 5 months and live weight 30 kg, were fed for 57 days, with isoenergetic diets (72% TDN), but with different protein levels (12, 16, 20 and 24% PB). The animals were identified, weighted and distributed in the four treatments. The lambs were kept underroof in individual pens with lathing and a suspended floor. The studied parameters were weight daily gain, dry matter intake, feed efficiency, and cost per kilogram of carcass. The use of diets with different protein levels in lamb termination, showed a positive linear effect for weight daily gain and negative feed efficiency. It was verified that the use of diets with increasing protein levels did not influence the dry matter intake of the lambs. It was concluded that the diets between 12 and 24% crude protein were economical for finishing lambs in drylot, however, the largest return were gotten with the ration contends 12% CP. There were no sex effects for the analyzed parameters.

Desempenhos reprodutivo e produtivo de ovelhas Santa Inês suplementadas em diferentes fases da gestação

The reproductive and productive behaviour of Santa Ines ewes were evaluated as a function of supplementation in different stages of pregnancy, where NS = pasture during the day and cassava bagasse during the night over the breeding season and pregnancy, S46 = NS plus supplement (soybean hulls) from the 46th day after the beginning of the breeding season until the birth and S100 = NS plus supplement (soybean hulls) from the 100th day after the beginning of the breeding season until the birth. Ninety-Four Santa Ines ewes were utilized, mating by five Santa Ines and five Dorset ram. The treatment did not affect ewe weight on the 84 days after the beginning of the supplementation (EW 4), weight of the ewe at the weaning (WEW), pregnancy incidence (0 or 1) at the final third part of it (PREG), birth rate (BIRTH), natality rate (NR) and prolificity (PROLI), being the averages of 49.54 kg; 0.82; 0.71; 0.88 and 1.26 respectively. Ewes supplementation, sex and genetic group of the lamb did not influence the birth weight (LWB), by the age of 30 days (LW30) and by the 60 days (LW60). The averages were, respectively, 3.47 kg; 8.26 kg and 12.42 kg. The type of birth affected the LWB and the LW30. There was no difference for the total weight of the lambs at birth (TWB), total weight of the lambs after 30 days (TW30) and total weight of the lambs after 60 days (TW60) between the treatments, inside each type of birth and among the genetic groups. The supplementation stages of the ewe, the genetic group of the lamb and the type of birth did not influence the death rate, from the birth until the age of 30 and 60 days. The reproductive performance of the supplementeds ewes in the pregnancy period using 0.5% of live weight, with soybean hulls, was not modified.

Características de carcaça de cordeiros terminados em confinamento, com dietas contendo diferentes níveis protéicos

Thirty two tricross lambs were finished (1/2 Texel + ¼ Bergamacia + ¼ Corriedale), 16 males and 16 females, were fed for 71 days, with isoenergetic diets (72% TDN), but with different protein levels (12,16,20 and 24% PB) and kept indoors in individual pens. The carcass were evaluated after slaughter. The average net carcass yield was 54%, while the average commercial carcass yield was 48%. It was verified that protein levels between 12 and 24% did not affect hot and cold carcass weights; commercial carcass yield, indexes of compactness of the carcass, and ham, as well as the body condition, carcass conformation, fat covering, fat consistency, meat color, fat thickness and fat deposition. The animals finished with 12% crude protein in the diet showed the highest carcass yield.

Desempenho Produtivo, Econômico e Composição Química da Carne de Cordeiros Santa Inês (SI) e ½ Dorper + ½ Santa Inês (½ DSI), Abatidos com Diferentes Espessuras de Gordura Subcutânea

Foram utilizados trinta quatro cordeiros, sendo 16 Santa Ines (SI) e 18 ½ Dorper + ½ Santa Ines (½ D+ ½ SI), abatidos com diferentes espessuras de gordura subcutânea a fim de verificar o efeito do grupo racial e espessura de gordura ao abate, sobre o desempenho produtivo, economico e a composicao quimica da carne de cordeiros. Os animais permaneceram confinados, do desmame ao abate, recebendo racao completa, calculada para ganho medio diario de 0,300 kg. Foram realizadas avaliacoes por ultrassonografia na regiao do lombo entre a 12a e 13a costelas, os abates foram realizados a medida que os cordeiros atingiam a espessura de gordura pre-determinada: 2,0; 3,0 e 4,0mm. O peso final foi influenciado de maneira positiva pelas espessuras de gordura subcutânea ao abate. Os animais abatidos com 3,0 e 4,0 mm de espessura de gordura subcutânea apresentaram pesos de carcaca fria superiores aos abatidos com 2,0mm. Os animais abatidos com 2,0 e 3,0 mm de espessura de gordura subcutânea tiveram melhor conversao alimentar. Os cordeiros do grupo racial ½ Dorper Santa Ines apresentaram maior renda liquida, e esta aumentou com a espessura de gordura subcutânea dos cordeiros. Recomenda-se a producao de carne de cordeiros utilizando-se o grupo racial ½ Dorper Santa Ines e o abate com 4,0mm de espessura de gordura subcutânea. DOI:10.15528/2176-4158/rcpa.v14n2p215-218