O objetivo deste experimento foi determinar a qualidade e o valor nutritivo de silagens do subproduto da pupunha, produzidas com aditivos, conforme os tratamentos: T1 - Testemunha (sem aditivo); T2 - Adição de 2,5% de açúcar; T3 - Adição de 10,0% de polpa cítrica e T4 - Adição de 10,0% de milho moído, base da matéria natural. Verificou-se que a adição 10% de polpa cítrica (PC) ou milho moído (MM) elevou o teor de matéria seca da massa a ser ensilada, bem como da silagem, em 6,5 e 8,0 unidades percentuais, respectivamente. Silagens com aditivos apresentaram menores valores de nitrogênio amoniacal (N-NH3 / NT) e pH. O consumo de matéria seca foi maior para as silagens feitas com PC ou MM, atingindo 85 g/kg PV0,75 ou 2,1% do PV, contra 44,7 g/kgPV0,75 ou 1,12%, para as silagens sem aditivo ou com 2,5% de açúcar. O coeficiente de digestibilidade aparente da matéria seca, também foi superior para as silagens contendo 10% de PC ou MM (65,0%) em relação à média das demais (52,0%). A digestibilidade da parede celular não mostrou tendência definida em função dos tratamentos. A silagem de subproduto da pupunha feita com a adição de 10% de polpa cítrica ou milho moído, apresentou valor nutritivo semelhante às silagens de forrageiras convencionais.

Intake of tropical grass forages alone is generally insufficient to avoid nutrition imbalances and reduced animal performance; therefore, supplementation is often recommended. The hypothesis of the present study is that when combined with fat, soybean hulls (SH) could replace corn as a source of energy, reducing methane production without affecting animal performance. This study evaluated the effects of starch-based supplementation level combined with oil on intake, digestibility, performance, and methane emissions of growing Nellore bulls (P = 44; initial BW = 250.69 ± 27 kg) fed cv. Xaraés during the rainy season. There were no interactions between starch level and oil supplementation with regard to intake of DM (P = 0.67), forage DM (P = 0.55), supplement DM (P = 0.14), OM (P = 0.66), CP (P = 0.74), NDF (P = 0.50), ether extract (EE; = 0.47), and GE ( P= 0.68). The intake of EE was greater for animals supplemented with oil than those fed supplements without oil (P < 0.01). There were no interactions between starch level and oil supplementation on digestibility of DM (P= 0.18), OM (P = 0.11), NDF (P= 0.42), and EE (P = 0.14). Moreover, there was interaction between starch and oil supplementation on GE (P < 0.01). Independent of starch level used, the addition of oil decreased the digestibility of OM (P = 0.04) and NDF (P = 0.03). There were no main effects of starch level, oil, or interaction between starch and oil for initial BW (P = 0.10), final BW (P = 0.94), ADG (P = 0.40), feed efficiency (P= 0.37), and carcass gain (P = 0.38). There was no interaction between starch-based supplementation level and oil on methane emissions when expressed in grams per day (P = 0.77), kilograms per year (P = 0.77), grams per kilogram DMI (P = 0.53), and grams per kilogram carcass gain (P= 0.31). There was, however, an interaction (P = 0.04) between starch level and oil on methane emissions when corrected for NDF intake. Additionally, oil decreased enteric methane emission for intake of GE (P = 0.04) and EE (P < 0.01) of animals fed with starch level. Soybean hulls have an estimated feeding value similar to that of corn. The use of oil supplementation may be effective to reduce enteric methane emission of Nellore bulls raised on pasture.

SUMMARYThe use of diets with increasing proportions of concentrate to fibre can ensure appropriate energy levels and result in greater efficiency in Nellore feedlot steers. It was hypothesized that higher proportions of concentrate in the diet of these Nellore steers may affect ruminal fermentation and microbiota as a consequence of ruminal pH reduction. The present study was conducted to evaluate the effect of diets with four different roughage (hay Tifton 85) : concentrate ratios on intake, digestibility, rumen fermentation and rumen microbiota of Nellore feedlot steers. Higher proportions of concentrate in the diet did not affect intake and digestibility of dry and organic matter. The concentration of N-NH3, total rumen volatile fatty acid, acetic (C2), butyric (C4), isobutyric, valeric and isovaleric acids, and microbial nitrogen did not differ among diets. However, increasing proportions of concentrate in the diet resulted in a linear reduction in average rumen pH and increased propionic acid (C3) concentration, resulting in lower relative C2 : C3. Bacterial population of Fibrobacter succinogenes, Ruminococus flavefaciens and Ruminococcus albus decreased in the rumen. However, bacteria that are consumers of lactic acid (Selenomonas ruminantium and Megasphaera elsdenii) and producers of lactic acid (Lactobacillus sp. and Streptococcus bovis) increased when animals were fed with high-concentrate diets. The total number of protozoa was similar for the different roughage : concentrate ratios. Protozoan counts were only influenced by diet for the genus Dasytricha. The findings point to diets with increasing concentrate to Tifton 85 hay ratios as inhibiting the growth of some cellulolytic bacteria and reducing fibre digestibility, and indicate Tifton 85 hay as a possible modulated rumen fermentation in the Nellore steer feedlot.

RESUMO -O objetivo do trabalho foi avaliar comparativamente as características de carcaça e a composição corporal de machos jovens da raça Nelore não-castrados, filhos de touros com diferencial positivo (Linhagem Seleção) ou nulo (Linhagem Controle) para ganho de peso aos 378 dias de idade. Utilizaram-se informações de 92 zebuínos Nelore, com peso de abate médio de 456,00 kg, sendo 51 animais pertencentes à Linhagem Seleção e 41 animais da Linhagem Controle, foram criados em pastagens cultivadas até os 18 meses, quando foram alocados nos dois sistemas de terminação, de forma a compor grupos homogêneos quanto ao peso e filiação. Os animais de confinamento receberam, em baias individuais, ração para possibilitar ganhos de 1,0 kg/cab/dia. Antes do abate, os animais foram submetidos a jejum e pesados, quando se obteve o peso de abate. Após o armazenamento das carcaças em câmara fria, obteve-se a seção da 9 a -10 a -11 a costelas. Não houve efeito significativo de linhagem para nenhuma das características analisadas, exceto para a porcentagem de ossos, sendo que os animais da Linhagem Seleção superaram os animais da Linhagem Controle. O regime de terminação apresentou efeito significativo para a quase totalidade das características estudadas, com exceção para as características de composição corporal. Não houve efeito significativo de interação entre linhagem e terminação. As classes de idade apresentaram efeito significativo para as características peso de abate, peso de carcaça quente, peso da gordura renal-pélvica-ingüinal, porcentagem de músculo, gordura e osso.Palavras-chave: bovino de corte, produção de carne, qualidade da carne, seleção, zebuínos Carcass Traits and Body Composition of Young Nellore Bulls Finished at DifferentFeeding Regime ABSTRACT -The objective of this work was to evaluate comparatively the carcass traits and body composition of young Nellore breed intact male, sons of bulls with differentials positive (Selection Lineage) or null (Control Lineage) at weight gain at 378 days of age. Data from 92 Nellore cattle, with 456.00 kg of slaughter weight, being 51 animals of Selection Lineage and 41 animals of Control Lineage. They were raised in cultivated pastures until 18 months of age, when were designated in two finishing systems, to arrange homogeneous groups to weight and filiation. The animals were fed, in individual pens, with ration for gains of 1.0 kg/day. Before slaughter, the animals were fasted and weighed, when the slaughter weight was obtained. After carcass storage in cold chamber, the section of 9 th -10 th -11 th ribs was obtained. There were no significant effects of lineage were for neither traits studied, except for the bone percentage, and the animals of Selection Lineage were superior than the animals of Control Lineage. The finishing system showed significant effects for all traits studied, except for the body composition. There were no significant effects of interaction between lineage and finishing system. The classes of age showed significant effects for the traits slaughte...

The objective of this experiment was to determine the effect of crude glycerin combined with soybean oil on the performance and fatty acid composition of the longissimus muscle in Nellore bulls. Twenty-eight Nellore young bulls, each with an initial body weight (BW) of 408 ± 29 kg (age 20 ± 2 months), were used in a completely randomized design over a period of 84 days in a 2 × 2 factorial arrangement. The treatments were diets with crude glycerin at 100 g/kg DM (CG+) or without crude glycerin (CG−); diet with inclusion of soybean oil at 60 g/kg DM (Oil+) or without soybean oil inclusion (Oil−). All diets were composed of corn silage (400 g/kg DM), used as the only source of roughage, and concentrate (600 g/kg DM). The intake of the dry matter (g/kg of body weight), neutral detergent fiber (aNDF) and crude protein decreased with soybean oil inclusion, independent of crude glycerin addition. The aNDF digestibility decreased in diets with soybean oil and without crude glycerin. The DM and organic matter (OM) were most digestible in diets that added crude glycerin but excluded soybean oil. Animals fed soybean oil without crude glycerin exhibited higher intake of linoleic acids, total unsaturated fatty acids (UFA), and total polyunsaturated fatty acids (PUFA) than those fed other diets. There were no effects of oil or crude glycerin feeding on final body weight, average daily gain (ADG), hot carcass weight, subcutaneous fat thickness, or loin eye area (P > 0.05). Animals fed soybean oil incorporate into the muscle 40% more conjugated linoleic acids (CLA) and 32% more linoleic acids compared to other diets. The addition of crude glycerin decreased the elongase index (P = 0.04) in the longissimus muscle. The combination of crude glycerin and soybean oil did not effectively increase performance or unsaturated fatty acid deposition in meat. However, the addition of soybean oil at 60 g/kg DM optimized feed efficiency and did not alter ADG.

-The effects of overfeeding with protein of different degradability on body condition, plasma urea nitrogen and progesterone concentrations, ovulation number and follicular dynamics were assessed in Santa Ines ewes.Twelve ewes were assigned to a randomized block design according to body weight and received overfeeding with soybean meal or with corn gluten meal or maintenance diet for 28 days before ovulation and during the next estrous cycle. Blood samples were taken on days 7, 14, 21, and 28 after the beginning of treatments for analysis of plasma urea nitrogen and on days 3, 6, 9, 12, and 15 into the estrous cycle for analysis of plasma urea nitrogen and progesterone. Follicular dynamics was monitored daily by ultrasound during one estrous cycle. Dry matter and crude protein intake, weight gain, plasma urea nitrogen concentration before ovulation, number of ovulations, diameter of the largest follicle of the 1st and of the 2nd waves and the growth rate of the largest follicle of the 1st wave were higher in the ewes that received overfeeding. The growth rate of the largest follicle of the 3rd wave was higher in the ewes fed maintenance diet. The back fat thickness, plasma urea nitrogen before ovulation and progesterone concentrations, diameter of the largest follicle of the 2nd wave and growth rate of the largest follicle of the 3rd wave were higher in ewes that received overfeeding with soybean meal. The growth rate of the largest follicle of the 1st wave was higher in ewes that received overfeeding with corn gluten meal. Overfeeding with protein-rich feeds may increase the ovulation number and with soybean meal, it may be effective in increasing plasma progesterone concentration in ewes.

Este estudo foi realizado com o objetivo de avaliar a concentração plasmática de N-ureico, o número de ovulações e o diâmetro do folículo ovulatório de ovelhas da raça Santa Inês submetidas a sobrealimentação com fontes de proteína de diferentes degradabilidades ruminais. Quarenta e quatro ovelhas com o estro sincronizado receberam dietas isoproteicas, formuladas com farelo de soja (n=24) ou com glúten de milho e farelo de algodão (n=20) durante 28 dias antes da ovulação. Os animais foram distribuídos em delineamento de blocos, com os blocos formados por três faixas de escore de condição corporal. O ganho de peso vivo e de escore de condição corporal, o peso vivo e o escore de condição corporal no 28º dia do experimento, a concentração plasmática de N-ureico, o número de ovulações e o diâmetro do folículo ovulatório não diferiram entre as ovelhas submetidas à sobrealimentação com farelo de soja ou com glúten de milho e farelo de algodão. As ovelhas que receberam sobrealimentação com farelo de soja apresentaram maior concentração plasmática de N-ureico nos dias 7 e 14 e menor no dia 28 em comparação às que receberam sobrealimentação com glúten de milho e farelo de algodão (interação dieta vs dia). O fornecimento de uma dieta com menor teor de proteína degradável no rúmen não reduz concentração plasmática de N-ureico nem altera o número de ovulações e o diâmetro do folículo ovulatório.

Soybean hulls as feed substitute of ground corn can increase the fiber digestibility and bacterial fibrolytic profile of grazing Nellore steers during the rainy season Casca de soja como substituto do milho moído pode aumentar a digestibilidade da fibra e o perfil fibrolítico bacteriano de novilhos Nelore em pastejo durante a estação chuvosa AbstractThis study aimed to evaluate the effect of replacement of ground corn by soybean hulls associated or not to whole soybean grain in the feed supplement on intake, nutrient digestibility, rumen microbial population, and fermentation parameters of growing Nellore steers grazing Brachiaria brizantha cv. Xaraés during rainy season. Were used eight castrated Nellore steers (425 ± 36 kg of body weight (BW)) fitted with ruminal and duodenal cannulas in a replicated 4 × 4 Latin square with a 2 × 2 factorial arrangement, allocated into 4 paddocks of 0.25 ha each, consisting of Brachiaria brizantha cv. Xaraés and supplemented with: (1) ground corn combined with whole soybean grain (SG); (2) ground corn without SG; (3) soybean hulls (SH) combined with SG; and (4) SH without SG. Supplement intake was no affected by SG or SH (mean 2.12 kg -1 d, P > 0.05). There were no interactions between SH and SG on DM and nutrients intake (P > 0.05). The addition of SG reduced the dry matter (DM) intake expressed as % of BW and Kg -1 d, as well forage DM, organic matter (OM), crude protein (CP), neutral detergent fiber (aNDF), and gross energy (GE) intake (P ≤ 0.01). Animals supplemented with SH without SG had greater digestibility of DM (74.52), OM (77.62), CP (77.51), NDF (71.93) and GE (72.90) than animals supplemented with SH with SG (DM =69.01, OM = 71.92, CP = 72.81, NDF = 66.01, GE =68.01) expressed as % (P ≤ 0.01). The addition of SG in the supplements declined the ruminal pH and NH 3 -N (P=0.02). Animals supplemented without SH without SG showed greater Entodinium counts (6.01 n x 10 4 ml -1 , P=0.04), and SG supplementation decreased the numbers of Dasytricha, Isotricha, and ruminal total protozoa (P < 0.01). The abundance of Ruminococcus albus, R. flavefaciens, and Archaeas were higher for SH without SG supplement. Additionally, animals supplemented with SG had lower numbers of Fibrobacter succinogenes. The use of soybean hulls without whole soybean grain in the supplement may be effective to increase fiber digestibility, N retained, R. albus and R. flavefaciens in the rumen of Nellore steers grazing Brachiaria brizantha cv. Xaraés during the rainy season. Resumo Este estudo avaliou o efeito da substituição do milho moído por casca de soja associado ou não a grãos de soja no suplemento de novilhos Nelore em crescimento pastejando Brachiaria brizantha cv. Xaraés durante a estação chuvosa sobre o consumo, digestibilidade de nutrientes, população microbiana ruminal, e parâmetros de fermentação de novilhos Nelore (425 ± 36 kg de peso corporal (PC)) em crescimento pastejando Brachiaria brizantha cv. Xaraés durante a estação chuvosa. Foram utilizados oito novilhos Nelore com cânulas no rúm...