ResumoO presente estudo objetivou avaliar a influência de rações com diferentes níveis de energia metabolizável sobre o teor de lipídeos totais, colesterol e perfil de ácidos graxos no músculo Longissimus dorsi de cordeiros Santa Inês. Foram utilizados 20 cordeiros, com idade e peso de 50 dias e 13,0 ± 0,56 kg, respectivamente, alimentados com rações contendo diferentes níveis energéticos: 2,08; 2,28; 2,47 e 2,69 Mcal/kgMS. Os animais foram pesados semanalmente para acompanhamento do ganho de peso vivo, quando a média do peso vivo do tratamento atingiu 28 kg, os animais foram abatidos. A análise do perfil lipídico do músculo Longissimus dorsi apresentou efeito linear crescente e decrescente para os ácidos Cis-10 heptadecanóico (C17:1) e eicosatrienóico (C20:3), respectivamente, com o aumento nos níveis de energia dietéticos (P<0,05). Os níveis de colesterol (mg/100g) decresceram em relação ao aumento nos níveis de energia das rações. As relações ácidos graxos poliinsaturados (AGPI):ácidos graxos saturados (AGS); AGPI:ácidos graxos monoinsaturados (AGM); AGM:AGS; ácidos graxos desejáveis, w-6:w-3, índice de aterogenicidade, índice de trombogenicidade, relação entre os ácidos graxos hipercolesterolêmicos e hipocolesterolêmicos e a relação (C18:0 + C18:1):C16:0 não foram influenciadas pelos níveis energéticos (P>0,05). A manipulação dietética influencia o perfil lipídico no Longissimus dorsi de cordeiros Santa Inês. Palavras-chave: Ácidos graxos insaturados, carne de cordeiro, índice de aterogenicidade AbstractThis study evaluated the influence of rations with different levels of metabolizable energy on the content of total lipids, cholesterol and fatty acid profile of the longissimus dorsi of Santa Ines lambs. Twenty Santa Ines lambs were used, with age and body weight of 50 days and 13.0 ± 0.56 kg, respectively, fed rations with different energy levels: 2.08; 2.28; 2.47 e 2.69 Mcal/kgDM. Animals were weighed weekly

The objective of this study is to provide approaches to determine mature weight of female and intact and castrated male Saanen goats using body composition data. Our database combined 7 comparative slaughter studies and comprised 244 individual records of body composition of intact male ( = 94), female ( = 71), and castrated male ( = 79) Saanen goats weighing from 4.6 to 51.0 kg BW. Nonlinear regressions were fitted to predict empty body water, fat (EBF), protein (EBP), and ash, expressed as amounts and percentages of the empty BW (EBW) and water-free EBW. Candidate equations were selected on the basis of preliminary graphical examination of the observed body composition of the database, and the best one to describe the data was selected on the basis of convergence achievement with coherent biological interpretation. The selected nonlinear functions were the allometric function (Y = β × EBW) to describe the EBF content and the exponential function (Y = β × × EBW) to describe EBP content in the water-free matter basis. None of the tested nonlinear functions were able to describe ash content, possibly because of its large variation. Mature weight was assumed to be the weight when net protein deposition (i.e., accretion minus degradation) tended to zero. The EBP (percentage of water-free EBW) plotted against the EBW using the exponential function enabled us to estimate the mature weight of intact and castrated males and females as 83.9, 33.6, and 26.4 kg EBW, respectively, indicating that the decrease of protein accretion of intact males approaches zero later than in females and castrated males during growth. Replacing these mature EBW estimates in the allometric function to describe the fat content in the EBW, we estimated that at maturity, castrated males and females had 21.6% and 22.4% EBF, whereas intact males had 36.8% EBF, which may not be biologically acceptable because it is too high. On the other hand, assuming that a goat matures at 22% EBF, one can backward estimate mature EBW of 42.6, 34.9, and 26.0 kg for intact and castrated males and females, respectively. This study indicated that fat percentage in the body may be used to describe maturity, as long as dietary challenges are not imposed on the animals. In addition, our results confirmed that female Saanen goats reach maturity at a lighter weight than males.

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Resumo -Objetivou-se com esse estudo avaliar trocas gasosas e índices de crescimento no capim-braquiária manejado sob cinco lâminas de irrigação (3,84; 4,39; 6,19; 8,62 e 10,46 mm dia -1 ) e quatro idades, num delineamento inteiramente casualizado em arranjo de parcelas subdivididas, sendo as lâminas de irrigação estudadas nas parcelas e as idades (10, 17, 24 e 31 dias) nas subparcelas, com quatro repetições. Constatou-se interação entre lâminas de irrigação e idades nas variáveis: transpiração foliar, temperatura da folha, taxa de fotossíntese e razão de peso foliar. Verificou-se resposta quadrática com ponto de mínimo para a concentração interna de CO 2 e área foliar específica (0,0055 m² de folha g -1 de folha) em função do avanço nas idades. A concentração interna de CO 2 apresentou valores estimados em 220,09 e 176,20 ppm aos 10 e 31 dias de crescimento, respectivamente, com valor mínimo (173,68 ppm) aos 27 dias. Verificou-se resposta quadrática com ponto de máximo (25,04 g m -2 de folha dia -1 ) para a taxa de assimilação líquida com o aumento nas idades. Observou-se resposta linear decrescente para taxa de crescimento relativo e razão de área foliar com aumento nas idades. A taxa de crescimento relativo revelou valores de 0,097 e 0,048 g g -1 dia -1 , com 10 e 31 dias de crescimento, respectivamente. As idades de crescimento proporcionam mudanças nas trocas gasosas e nos índices de crescimento do capim-braquiária, porém, tais variáveis são pouco influenciadas pelas lâminas de irrigação nas condições do presente estudo.Palavras-chave -Taxa de assimilação líquida. Taxa de crescimento relativo. Taxa de fotossíntese foliar. Transpiração foliar. Temperatura da folha.Abstract -This research aimed to evaluate the gas exchange and growth index of Brachiaria decumbens under five water supply (3.84, 4.39, 6.19, 8.62 and 10.46 mm day -1 ). A completely randomized with split-plot design with five irrigation depth being the parcels and ages (10, 17, 24 and 31 days), the subparcels, with four replicates. It was observed interaction between irrigation depth and ages for leaf transpiration, leaf temperature, rate of photosynthesis and leaf weight ratio. Quadratic responses with minimum values were observed to the internal CO 2 concentration and specific leaf area (0.0055 m² leaf g -1 leaf) with advance in ages. The internal concentration of CO 2 revealed values of 220.09 and 176.20 ppm to 10 and 31 days, respectively, with minimum (173.68 ppm) to 27 days. It was observed quadratic response with maximum value (25.04 g m -2 leaf day -1 ) to the net assimilation rate with increasing ages. Decreasing linear responses were observed to the relative growth rate and leaf area ratio with increasing ages. The relative growth rate presented values of 0.097 and 0.048 g g -1 day -1 , with 10 and 31 days, respectively. The growth ages provided changes on gas exchange and growth index of Brachiaria grass, however, these characteristics are little influenced by irrigation depth under the conditions of this study.

-This study was carried out to estimate efficiencies of the utilization of metabolizable energy for maintenance (k m ) and weight gain (k g ) and to evaluate the Small Ruminant Nutrition System (SRNS) model in predicting dry matter intake and average daily gain of growing Santa Ines sheep. Twenty-four non-castrated Santa Ines sheep, at 50 days of age and with average body weight of 13.00 ± 0.56 kg, respectively, were used. After a 10-day adaptation period, four animals were slaughtered to be used as reference for estimating initial empty body weight and body composition of the other animals.The remaining animals were distributed in a random block design, with the treatments consisting of diets containing different levels of metabolizable energy (2.08, 2.28, 2.47 and 2.69 Mcal/kg of DM), with five replicates. The metabolizable energy use efficiencies for maintenance and for weight gain were calculated from the relationship between the dietary net energy for maintenance and gain and ME concentration in the diets. Evaluation of the SRNS model was performed by adjustment of simple linear regression model between the predicted (independent variable) and observed (dependent variable) values. The estimated energy use efficiency for maintenance (k m ) was 0.70; and for gain weight (kg) it showed to be inversely proportional to the increase of metabolizable energy concentration in the diet. The dry matter intake predicted by the SRNS model did not statistically differ from that observed, but the model overestimated the average daily gain by 5.18%. Those results can contribute to the construction of a database, which could be condensed into several others in a predictive model of performance and feed planning for sheep reared in Brazil.