ABSTRACT This study aimed to evaluate the effects of sunflower meal (SFM) inclusion on the performance, nutrient digestibility, and respirometric parameters in sheep. Twenty-four Dorper × Santa Inês uncastrated males, with an average age of 5 mo and initial body weight (BW) of 27.91±6.0 kg, were distributed in a randomized block design with four treatment diets containing 0, 100, 200, and 300 g of SFM/kg of total dry matter, replacing soybean meal. Intake, weight gain, ingestive behavior, and in vitro digestibility were evaluated according to the SFM inclusion. The respirometric parameters were evaluated in an open-circuit respirometric chamber. There was a quadratic response in dry matter intake expressed according to the SFM inclusion, with minimum points of 90.56 g/kg 0.75 BW for inclusion levels of 96 g of SFM/kg. A linear decrease in the in vivo digestibility of dry matter, neutral detergent fiber, and non-fibrous carbohydrate and in vitro fermentation of dry matter and fibrous carbohydrates was observed in response to SFM inclusion. These results reflect the higher fiber content of the byproduct, which reduced the non-fibrous carbohydrates in the diets. Despite the change in nutrient availability, average daily gain (299 g/day), O 2 consumption (26.24 L/kg 0.75 BW), and CH 4 production (2.25 L/kg 0.75 BW) were not influenced by the SFM inclusion, indicating that changes in the nutritional value of the diet did not affect the animals’ energetic metabolism. Sunflower meal inclusion decreased the digestibility but did not affect the animal gain and the respirometric parameters. The SFM can replace soybean meal in the diet of growing lambs; however, it has a maximum inclusion point of 88 g SFM/kg for feed conversion, which is a necessary factor for evaluating the replacement cost.

ABSTRACT Growth performance, organ biometrics, bone characteristics, and intestinal morphometry were evaluated in broilers fed a diet containing orange (Citrus sinensis L.) essential oil. A completely randomized design was used, with five treatments with orange essential oil (0, 100, 200, 300, and 400 mg kg−1 diet) and six replications with 20 birds per experimental unit. In the pre-starter phase, feed intake and weight gain of all birds linearly increased, while feed conversion decreased with the addition of orange essential oil in the feed. At day 21, bone density (Seedor Index) and body weight were higher in the birds that received the maximum level of essential oil (400 mg kg−1) compared with those not treated with essential oil. The observed effects resulted from the better functioning of the physiological mechanisms of digestion and absorption of nutrients, characterized by the increase in villus height. Glycemia and weights of gastrointestinal tract organs of broilers at 21 days of age were not influenced by the evaluated essential oil. The results show that the addition of phytogenic additives to the diet does not cause any physiological impairment in birds.

RESUMO: O objetivo desse estudo foi avaliar o teor de fibra fisicamente efetiva (FDNfe) de dietas totais e seus efeitos nos nutrientes da dieta, das sobras e nos parâmetros fecais de bovinos de corte em 15 confinamentos comerciais. As amostras da dieta foram separadas utilizando a peneira Penn State Particle Size Separator (PSPS). As amostras foram analisadas quanto aos teores de matéria seca (MS), matéria mineral (MM), extrato etéreo (EE), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e amido. Nas amostras de fezes também foram avaliadas o escore e pH fecal. Os confinamentos foram categorizados em dois tratamentos: FDNfe<20% e FDNfe≥20%. Os dados foram analisados por um modelo que incluiu os efeitos de grupo e covariável (sexo e grupo genético). Os teores de MS, PB, EE e amido foram menores nas dietas com FDNfe≥20%(P<0,05). A MS fecal foi maior e pH fecal matinal foi menor nas dietas com FDNfe<20% (P<0,05). Sendo assim a efetividade da fibra alterou os nutrientes da dieta total e sobras, bem como as variáveis pH e MS fecal. Com isso, o uso de PSPS e parâmetros fecais são ferramentas práticas e indiretas para medir o amido fecal e a efetividade da dieta em confinamentos de bovinos comerciais.

ABSTRACT: This study evaluated the effects of the physically effective fiber (peNDF) content on nutrient composition of the total mixed ration (TMR), orts and fecal parameters in 15 commercial beef feedlots. The particle size distribution of TMR was measured adopting Penn State Particle Size Separator (PSPS). Samples were evaluated for dry matter (DM), ash, ether extract (EE), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch content. Fecal samples were also evaluated for pH and score. The feedlots were categorized into peNDF<20% and peNDF ≥ 20%. Data were analyzed by a model that included fixed effects of treatment and covariates (sex and genetic groups). Levels of DM, CP, EE and starch were lower in TMR with peNDF ≥ 20% (P<0.05). Fecal dry matter was higher and morning fecal pH was lower for TMR with peNDF<20% (P<0.05). Physically effective fiber changed nutrient levels in TMR, orts, fecal pH and DM. So, using PSPS and fecal parameters are practical and indirect tools for measuring fecal starch and assessing the effectiveness of the diet supplied to ruminants.

RESUMO O objetivo deste trabalho foi avaliar a influência dos fatores ambientais sobre o desempenho das progénies de diferentes touros da raça Nelore no semiárido brasileiro. Informações de 741 animais foram coletadas de uma fazenda comercial localizada no municipio de Varzelândia-MG. Os animais eram filhos de 27 touros da raça Nelore e eram categorizados como LA (livro aberto) ou PO (puros de origem). Foram avaliados os dados de peso, ganho de peso médio diário e perímetro escrotal. As avaliações foram realizadas aos 12 (ano) e 18 (sobreano) meses de idade. Os dados foram analisados pelo método dos quadrados mínimos, utilizando um modelo que considerou efeito de categoria (LA ou PO), touro, anos, mês de nascimento e sexo dos bezerros. Houve influência significativa da categoria, sexo, mês de nascimento e touro sobre o desempenho dos animais até o ano, enquanto as características de desempenho ao sobreano foram influenciadas somente pelo mês de nascimento e touro (P<0,05). Sendo assim, os fatores do meio como ano e mês de nascimento e sexo do bezerro são importantes fontes de variação sobre o desempenho dos bezerros do nascimento até o sobreano, devendo, portanto, ser consideradas na comparação e seleção de animais com base nestas características.

SUMMARY The aim of this study was to evaluate the influence of environmental factors on the performance of progeny from different Nellore sires in Brazilian semiarid region. Data on live weight, average daily gain and scrotal circumference of 741 animals categorized as OR (open registry) or PB (purebred) and born from 27 sires were collected from a commercial farm located in Varzelândia-MG. Evaluations were taken at 12 (yearling) and 18months of age. Data were analyzed using the least-squares method, considering the effect of pedigree (OR or PB), sire, year of birth, month of birth and calf sex in the model. There was a significant influence of the pedigree, sex, month of birth and sire on animal's performance until yearling age, whereas the performance traits at 18months were influenced only by the month of birth and sire (P<0.05). Therefore, environmental factors such as year, month of birth and calf sex are important sources of variation on calf performance from birth to18 months and it should be considered when comparing and selecting animals based on these traits.

ABSTRACT. The objective of this work was to evaluate the performance, body morphometric measurements and testicular development in lambs fed with different rates of sunflower meal inclusion. The animals (24) were randomly distributed in treatments with 0, 10, 20 and 30% of sunflower meal in the dry matter of the diet, in six replicates, during 56 days of confinement. The addition of the coproduct at increasing dietary rates increased linearly the dry matter intake in the percentage of live weight and neutral detergent fiber. Despite this, there was a linear reduction in ether extract intake and chest width. On the other hand, there was no difference in daily, total and final weight gains. The body condition score; height of withers, croup and thorax; length of body and croup; width of fore croup, hind croup and chest; thoracic and neck diameters also did not change with the addition of the coproduct. The testicular measures 26.76; 6.11; 6.08; 5.22; 5.21; 4.80, and 4.81cm varied quadratically with the inclusion. Therefore, the inclusion of 30% of the coproduct changes nutrient intake and testicular biometry, but does not interfere in the body weight and development, being an economical alternative.

Feed processing can affect rumen development in new born calves, and potentially define animal performance. Two feed management systems, extruded starter (Ruter) with possible early weaning and ground starter (control), were evaluated in thirty-two Holstein calves (16 females and 16 males). Animals were randomly assigned to the treatments using a randomized block design with birth weight as a covariate. They were weaned when starter intake reached 800 g for two consecutive days. Twenty-one days after the weaning, males were slaughtered and the stomach compartments were isolated. Rumen and omasum fragments were processed for morphological evaluation. Animal performance, clinical condition and stomach compartment weight did not differ between the treatments (P> 0.05), despite weaning weight of animals receiving extruded starter being 5.68% higher than the control animals. Extruded starter stimulated cell proliferation of the ruminal epithelium (P <0.05), but did not affect the dimensions of the papillary rumen and omasum mitotic index (MI). The Ruter feeding system was potentially beneficial for weight gain and morphofunctional rumen development in lactating animals; however, this treatment did not allow early weaning as proposed by the feeding system.