Cristiane Leal dos Santos

Desenvolvimento Relativo dos Tecidos Ósseo, Muscular e Adiposo dos Cortes da Carcaça de Cordeiros Santa Inês

An experiment was carried out at the Sheep Production Sector of Federal University of Lavras to study the allometric growth of bone, muscular and fat tissues of commercial joints in lambs. Twenty-four Santa Ines lambs were used. The animals were kept confined in individual pens and fed ad libitum. The animals were slaughtered when they reached the target live weight of 15, 25, 35 and 45 kg. After the carcass had been dressed and chilled, the commercial joints were obtained from the left half part. The amount of the different tissues were got through the dissection of the leg, lion, rib, breast and shoulder. The allometric study was carried out using the model developed by HUXLEY(1932). The allometric coefficient of bone was lower than 1, the coefficient for the fat tissue was higher than 1 in all joints, and the muscular tissue in the ribs and shoulder were analysed for these joints, the coefficient was not different from 1.

Estudo alométrico dos cortes de cordeiros Santa Inês puros e cruzas

This study was conducted using 103 male and female lambs from the following genetic groups: purebred Santa Ines (SS) and crossbreds of Santa Ines x Texel (TS), Santa Ines x Ile de France (FS), and Santa Ines x Bergamacia (BS). Animals were slaughtered at one of the following body weights: 15, 25, 35 or 45 kg. After slaughter and cooling of the carcasses, the following cuts were made: neck, rib/flank, short ribs, loin, blade, and hindlimb. The alometric growth of each cut in relation to the empty body weight (EBW) was measured. The alometric growth of the neck was isogonic (b=1) for most genetic groups and accompanied EBW growth. However, for BS lambs the growth was heterogonic (b>1) or slow growth. TS and FS male lambs showed slower neck growth rate compared to the BS lambs. The rib/flank had slow growth for all groups but TS and FS lambs showed greater growth rate than the SS animals. For males, the blade development followed the EBW while females had a slower growth rate. The development of short ribs and loin was slow for all groups, except on FS female lambs, in which both short ribs and loin growth followed that of EBW; the alometric coefficients obtained for short ribs were lower on FS female lambs compared to those of the remaining genetic groups. The development of hindlimb accompanied the EBW for SS, TS and FS males and also for FS female lambs.

Estudo das curvas de crescimento de cordeiros das raças santa inês e bergamácia considerando heterogeneidade de variâncias

Funcoes de crescimento nao-lineares foram ajustados a dados de peso-idade de 40 cordeiros das racas Santa Ines e Bergamacia. Pelos testes de Hartley e de Bartlett, verificou-se que os dados apresentavam heterogeneidade de variâncias; em funcao disso, ajustaram-se as funcoes de crescimento pelo metodo dos quadrados minimos ponderado pelo inverso da variância dos pesos a cada pesagem utilizando a opcao WEIGTH do PROC MODEL (SAS INSTITUTE, 1996). As funcoes de crescimento foram comparadas pela interpretacao biologica dos parâmetros e pelos indicadores de qualidade do ajuste (coeficiente de determinacao ajustado, quadrado medio do residuo e teste de Durbin-Watson). As funcoes de von Bertalanffy e Gompertz apresentaram a melhor qualidade de ajuste, ao passo que as funcoes de Richards, Logistica e Brody nao se mostraram adequadas para descrever o crescimento dos animais por apresentarem estimativas nao condizentes com a realidade.

Influência do Fósforo, Micorriza e Nitrogênio no Conteúdo de Minerais de Brachiaria brizantha e Arachis pintoi Consorciados

This experiment was carried out in a greenhouse condition to study the effect of phosphorus, arbuscular mycorrhizal fungi and nitrogen on mineral accumulation in braquiaria MG-4 (Brachiaria brizantha cv. MG-4) above ground forage DM and peanut (Arachis pintoi cv. Amarillo) mixture, in soil of low fertility. The experimental design was a completely randomized in a 5x2x2 factorial arrangement, with five P rates (25, 50, 75, 100 and 200 mg/kg of soil), two inoculations (inoculated and no inoculated) and two levels of N (with and without N), with four replicates. The harvest of the above ground parts of plants was at 60 days after seed germination to determine the accumulated amounts of N, P, K, Ca, Mg and S. The phosphorus and mainly the nitrogen fertilization increased the accumulation of N, P, K, Ca, Mg and S in plant DM of braquiaria MG-4, however, this was not observed for mycorrhization. For forage peanut, a reduction of these minerals was observed with application of N, whereas the mycorrhization resulted in an increase of them. On the other hand, the phosphorus caused little increase in the accumulation of minerals in plant DM of peanut forage.This experiment was carried out in a greenhouse condition to study the effect of phosphorus, arbuscular mycorrhizal fungi and nitrogen on mineral accumulation in braquiaria MG-4 (Brachiaria brizantha cv. MG-4) above ground forage DM and peanut (Arachis pintoi cv. Amarillo) mixture, in soil of low fertility. The experimental design was a completely randomized in a 5x2x2 factorial arrangement, with five P rates (25, 50, 75, 100 and 200 mg/kg of soil), two inoculations (inoculated and no inoculated) and two levels of N (with and without N), with four replicates. The harvest of the above ground parts of plants was at 60 days after seed germination to determine the accumulated amounts of N, P, K, Ca, Mg and S. The phosphorus and mainly the nitrogen fertilization increased the accumulation of N, P, K, Ca, Mg and S in plant DM of braquiaria MG-4, however, this was not observed for mycorrhization. For forage peanut, a reduction of these minerals was observed with application of N, whereas the mycorrhization resulted in an increase of them. On the other hand, the phosphorus caused little increase in the accumulation of minerals in plant DM of peanut forage.

Crescimento alométrico dos tecidos ósseo, muscular e adiposo na carcaça de cordeiros Santa Inês e Bergamácia

The work was conducted with the objective to study the allometric growth of the bone, muscular and fat tissues in the left side of growing lamb carcasses. Thirty-six, twenty-four Santa Ines and twelve Bergamacia lambs were used. The animals were kept in individual pens and fed ad libitum diets. The slaughtering was done when the animals reached the live weight of 15, 25, 35 and 45 kg. The amount of the different tissues was obtained through the dissection of the left half of the carcass. The amount of the different tissues was obtained through the dissection of the leg, longissimus muscle, rib, breast and shoulder. The total amount of bone, muscle and fat tissues were obtained by the sum of each amount of commercial cut. The study of the relative tissue composition development was carried out using the model developed by HUXLEY (1932). A negative heterogonic (b 1) for the fat tissue in relation to the half side of the carcass was observed.

Composição centesimal da carne de cordeiros Santa Inês puros e de seus mestiços com Texel abatidos com diferentes pesos

The objective of this study was to evaluate the meat centesimal composition of Santa Ines pure breed and Santa Ines vs Texel crossbreed lambs, slaughtered at different body weights. Thirteen males and fourteen females from both breeds were selected. The muscle biceps femoris was used to determine water, crude protein, crude extract and minerals contents. The experiment was arranged randomly, with 16 traits in a 2x2x4 factorial scheme with two genetic groups, two genders (14 males and 13 females in each group) and four slaughter weights (15, 25, 35 e 45 kg of body weight). Data was analyzed by Proc GLM of SAS program. It was observed that the water content decreased as the slaughter weight increased, ranging from 76.09 to 74.31%. The males had higher water content values when compared to the females. The crude protein showed a quadratic behaviour, ranging from 20.27 to 21.36%. As the slaughter weight increased, the value of crude extract content also increased, ranging from 0.95 to 3.78%. The SIxSI animals presented higher ether extract content. In both genetic groups, the males presented lower ether extract content. The minerals content decreased as the slaughter weight increased and the females presented higher values when compared to the males. It was concluded that, as slaughter weight increased, the ether extract content also increased, while water and minerals content decreased and the crude protein content showed a linear decrease. The meat of female lambs presented higher contents of ether extract and less water content when compared to the meat of male lambs. The SIxSI lambs presented higher ether extract content when compared to TxSI lambs.