RESUMO -Objetivou-se estabelecer a zona de conforto térmico para ovinos da raça Santa Inês por meio da comparação das respostas fisiológicas em diferentes opções de temperatura em câmara bioclimática. O experimento teve duração de 71 dias e foi conduzido utilizando-se sete borregas da raça Santa Inês por tratamento. Os tratamentos foram as faixas de temperatura de 10, 15, 20, 25, 30, 35 e 40°C, com três repetições (dias de exposição) e cinco dias de intervalo. O delineamento experimental utilizado foi o inteiramente casualizado. Os dados meteorológicos coletados foram temperatura de bulbo seco, temperatura de bulbo úmido e temperatura de globo negro e os fisiológicos, frequência respiratória, frequência cardíaca, temperatura retal, temperatura timpânica, taxa de sudação e pressão arterial. Os mecanismos fisiológicos de dissipação de calor mostraram-se eficientes em manter a homeotermia dos animais em todas as temperaturas avaliadas. A temperatura de 25°C pode ser considerada a zona de conforto térmico para borregas da raça Santa Inês em ambiente com umidade relativa de 65%. Physiological data analyzed were: respiratory rate, heart rate, rectal temperature, tympanic temperature, sweating rate and blood pressure. The physiological mechanisms of heat dissipation are shown to be effective in maintaining the homeothermy of the animals studied at all temperatures. The temperature of 25ºC can be determined as the thermal comfort zone for SantaInes lambs in an environment with relative humidity of 65%.

The experiment was conducted to evaluate the ingestive behavior of lambs confined in individual and group stalls. We used thirty-four lambs in their growing phase, aged an average of three months, with mean initial live weight of 17.8±5.2 kg. They were allotted in a completely randomized design with 24 animals kept in individual stalls and 10 animals confined as a group. The experiment lasted for a total of 74 days, and the first 14 days were dedicated to the animals’ adaption to the management, facilities and diets. The data collection period lasted 60 days, divided into three 20-d periods for the behavior evaluation. The animals were subjected to five days of visual observation during the experiment period, by the quantification of 24 h a day, with evaluations on the 15th day of each period and an interim evaluation consisting of two consecutive days on the 30th and 31st day of the experiment. The animals confined as a group consumed less (p<0.05) fiber. However, the animals confined individually spent less (p<0.05) time on feeding, rumination and chewing activities and longer in idleness. Therefore, the lower capacity of lambs confined in groups to select their food negatively affects their feeding behavior.

The objective of this study was to assess the effect of substituting corn with soybean hulls on the ingestive behavior and nitrogen balance of Santa Ines lambs. A total of 25 lambs with an initial body weight of 20±2 kg at approximately six months of age, sheltered individually in stalls (1.10 m×1.0 m), considering an entirely casual experimental delineation. Soybean hulls were substituted for corn at 0, 250, 500, 750, and 1,000 g/kg of dry matter (DM). The time spent feeding, ruminating, masticating, and resting was not affected by the substitution of corn with soybean hulls. In fact, the feeding efficiency in g DM/h and the rumination efficiency in g DM/bolus increased linearly with soybean hull substitution in the feed. Although the nitrogen balance was not altered by the use of soybean hulls as a substitute for corn in the diets of Santa Ines lambs, the N ingested and N digested expressed in g/d, N retained as a percentage of that ingested, and N retained as a percentage of that digested displayed quadratic behavior. In conclusion, corn can be substituted with soybean hulls up to 1,000 g/kg of dry matter in the concentrate, without changing the ingestive behavior and nitrogen balance.

RESUMO -Foram estudados os efeitos da adição de 0,0; 0,75; 1,5 e 2,25% de óxido de cálcio no bagaço de cana-deaçúcar (com base na matéria natural) com o objetivo de avaliar o desempenho, o consumo de nutrientes e a digestibilidade aparente das dietas e dos nutrientes em ovinos mestiços da raça Santa Inês e raças nativas. Vinte e quatro ovinos, mantidos em total confinamento, foram distribuídos em delineamento inteiramente ao acaso, com quatro níveis de óxido de cálcio e seis repetições. Os animais foram mantidos em baias individuais, por 77 dias. Os primeiros 14 dias foram de adaptação e, então, seguiram-se três períodos de 21 dias de coleta de dados. Na determinação da digestibilidade, utilizou-se o método de coleta total de fezes, que foi realizada nos quatro últimos dias do período experimental. As fezes foram coletadas três vezes ao dia, às 7, 13 e 18 h. O uso do óxido de cálcio não influenciou os consumos de matéria seca, proteína bruta, fibra em detergente neutro, fibra em detergente ácido e nutrientes digestíveis totais, mas houve efeito linear sobre ganho de peso, com o aumento nas doses de óxido de cálcio, mas não sobre a conversão alimentar e os coeficientes de digestibilidade aparente da matéria seca, proteína bruta e fibra em detergente ácido. Entretanto, foi observado efeito quadrático para o coeficiente de digestibilidade aparente da fibra em detergente. A utilização do bagaço de cana hidrolisado com óxido de cálcio em níveis a partir de 1,5% da matéria natural promove melhoras no desempenho de ovinos e aumenta a digestibilidade apenas da fibra em detergente neutro. Palavras-chave: nutrição, pequenos ruminantes, resíduo industrialPerformance and nutrients apparent digestibility in sheep fed diets containing sugar cane bagasse treated with calcium oxide ABSTRACT -The addition effects of 0.0; 0.75; 1.5 and 2.25% of calcium oxide on sugar-cane bagasse (on natural matter basis) were studied to evaluate the performance, nutrients intake and apparent digestibility of the diets and nutrients in crossbred sheep of Santa Inês and native breeds. Twenty-four sheep, maintened in total confinement, were assigned in a completely randomized experimental design, with four levels of calcium oxide and six repetitions. Animals were kept in individual pens for 77 days. The first 14 days were for animals adaptation and three periods of 21 days of data collection.The method of total fecal collection was used to estimate digestibility, which was carried in four days at the end of the experimental period. Feces were collected three times a day, at 7 am, 1 and 6 pm. The intake of dry matter, crude protein, neutral detergent fiber, acid detergent fiber and total digestible nutrients were not influenced by the use of calcium oxide.There was a linear effect in daily weight gain with increasing calcium oxide dose. However, there was no treatment effect on feed conversion and apparent digestibility coefficients of dry matter, crude protein and acid detergent fiber. Whereas the quadratic effect was observed for neutral detergent...

This experiment was conducted to evaluate the intake, nutrient apparent digestibility and the effect of total collection days (two and four days) on apparent digestibility estimates for lambs fed diets containing sugar cane treated with calcium oxide (CaO). Eight Santa Inês castrated male lambs with a 16.6±1.8 kg body weight were used. The lambs were distributed in two 4×4 Latin squares, with four experimental periods of 14 d each. The animals were kept in 1.2 m2 individual pens, and the intake and digestibility evaluations were performed during the last four days of each period. The diets were formulated to be isonitrogenous, containing 14% crude protein (CP), and presenting 70% sugar cane treated with 0, 0.75, 1.5 or 2.25% of CaO (as-fed basis), corrected with 1% urea, and 30% concentrate. The sugar cane with added CaO was chopped, treated, and offered to the animals after 24 h of storage. The sugar cane with CaO increased the DM, OM, CP, NDF, NDFap, TC, NFCap and TDN intake (kg/d), when compared to natural sugar cane, and produced the same intake expressed as a percentage of body weight (% BW). The NFCap digestibility of the CaO-treated sugar cane was inferior to the NFCap digestibility in natural sugar cane. There was a linear increase in the DM intake with the CaO-added sugar cane, but the DM and NDF digestibility and the TDN content decreased linearly. The chemical treatment of sugar cane with CaO increases the intake but does not improve the nutrient digestibility. Two days of total fecal collection were found to be sufficient to estimate the total apparent digestibility in lambs.