Suchergebnisse

This study aimed to assess the probability of meat tenderness in confined cows. For this purpose, CAPES and SciELO platforms were searched for papers under this subject published in Brazil between 2000 and 2015. A total of 43 articles were found, of which eleven were used. Those selected approached the finishing of confined cows and specified animal genetic group, breed, and age at experiment start. Moreover, all these studies evaluated sensory and organoleptic characteristics of meat, following the same method. Each variable was analyzed by logistic regression, using the LOGISTIC procedure of SAS. The factors were evaluated by odds ratio (OR), in which changes in the probability of meat tenderness were estimated by means of an add-on function in regression variable units. Animal age at the beginning of termination, percentages of zebuine blood and heterozygosity, and marbling score are factors that affect (p < 0.30) the chance of beef tenderness. The probabilities of obtaining a tender meat increase when age at termination beginning and zebuine genotype participation are reduced, as well as when heterozygosity (via crosses) and meat marbling score increases.

This study aimed to assess the effect of sorghum planting patterns on forage response and performance of beef heifers at finishing phase. The experimental period lasted 84 days; treatments consisted of the combination of two interrow spacings (22 and 44 cm) and two sorghum-sowing rates (12 and 24 kg ha?1). Beef heifers, at finishing phase, with initial age of 15 months (± 2.3 months) and average body weight of 262 kg (± 37.95 kg), continuously grazed forage. The experimental design was completely randomized in a 2 × 2 factorial scheme with three repetitions per area. The different planting patterns did not affect (P > 0.05) dry matter production (5,447.78 kg DM ha?1) and accumulation rate (58.47 kg DM ha?1 day?1). Forage accumulation rate, leaf mass, forage mass, leaf supply and forage supply were influenced (P < 0.05) by time. Similar behavior was observed for stocking rate, weight gain per area unit and daily weight gain, with values of 1,172.32 kg of liveweight ha?1, 312.31 kg ha?1; 0.891 kg day?1, respectively. Animal performance had no effect (P > 0.05) from planting patterns, with nearly 4.04 mm of subcutaneous fat thickness and final weight of 330.36 kg. Animal body development showed no significant differences (P > 0.05), with values for length, heart girth and hip height of 132.01, 163.75 and 126.75 cm, respectively. The weight to average height ratio between planting patterns was 2.67 kg cm?1.

A nutrição materna na gestação tem sido recentemente associada à formação fetal e ao potencial produtivo da progênie na vida adulta. Uma das maneiras eficientes de avaliar o status nutricional da vaca gestante é através do escore de condição corporal (ECC). Desta forma, o objetivo do trabalho foi avaliar os efeitos da variação do ECC da vaca na gestação sobre o desempenho e características pós-abate da progênie. As progênies foram divididas conforme o desempenho das vacas: LOST, vacas que perderam 0,20 pontos de BCS; KEPT, vacas que mantiveram BCS; WON, vacas que ganharam 0,23 pontos de BCS no terço final de gestação. Foi avaliado o desempenho da progênie do nascimento até o abate, bem como as características da carcaça e carne dos animais. O delineamento experimental utilizado foi inteiramente casualizado com três tratamentos. Vacas WON apresentaram maior peso e ECC ao parto em relação às vacas LOST. O desempenho da progênie não foi influenciado pela variação do ECC da vaca na gestação (P>0.05), porém, apresentam comportamentos distintos entre as fases de crescimento. Durante a terminação em confinamento, novilhos LOST tenderam (P = 0.1013) a apresentar maior consumo de matéria seca em relação às progênies KEPT e WON (10.10 vs 9.75 e 9.24 kg dia-1, repectivamente). Novilhos WON foram mais eficientes para RFI (Residual Feed Intake) e mais produtivos para RWG (Residual Weight Gain) em relação aos animais LOST. Do mesmo modo, a progênie WON tendeu a apresentar maior deposição de gordura subcutânea (P = 0.0826) e de marmoreio (P = 0.0961) em relação aos novilhos LOST e KEPT. Desta forma, o acúmulo de escore corporal materno durante a gestação demonstra o atendimento das exigências para o crescimento fetal, aspecto que favorece o desenvolvimento e a formação de animais superiores.

The objective of this study was to evaluate the effect of crude protein substitution of soybean meal with urea (slow-release or otherwise) on the carcass and the meat characteristics of finished steers in confinement. Twenty-seven castrated, purebred and Charolais-Nelore crossbred steers with a mean age of 20 ± 1,5 months and initial mean live weight of 293 ± 31 kg, were distributed in three treatments: Protected Urea (concentrate containing slow degradation urea ); Soybean meal (concentrate containing soybean meal) and Urea Common (concentrate containing common urea). A randomized block experimental design (racial predominance) was used, with three treatments and nine replications, with the animal as the experimental unit. Feeding treatments did not influence the hot and cold carcass weight and yield. The fat thickness that covered the carcass was not altered, according to the diets studied, being on average 3.97 ± 0.94 mm. The measurements and the carcass compactness were not altered by the diets, presenting average values of 127.55; 74.86; 39.86; 38.84 and 25.72 cm for carcass length, leg and arm, arm perimeter and cushion thickness, respectively. A significant difference was observed in marbling, and the meat of the animals treated with soybean meal were higher than those treated with protected urea (3.72 vs 2.28 points).

This study aimed to verify the effects of supplying different energy patterns on ingestive behavior of feedlot-finished cattle. Twenty-seven pure and crossbred Charolais or Nellore steers with an initial average age and weight of 22 months and 252.8 kg, respectively, were used. Three treatments were carried out, two of them with an increasing rate of concentrate in the diet during the finishing period (IT5 and IT10) and one with constant roughage to concentrate ratio (CT). The experimental design was a completely randomized design with three treatments, five periods, and nine replications. Feeding time was higher for CT (4.31 hours) when compared to IT5 (3.85 hours). Steers from the treatment IT10 remained longer in lying leisure (8.14 hours) when compared to the treatment CT (7.24 hours). A superiority of chewing per ruminated bolus was observed in IT10 (58.59 seconds) when compared to IT5 (54.11 seconds) whereas a higher number of ruminated bolus was observed in TC5 (534.68 ruminated bolus day?1) when compared to IT10 (473.77 ruminated bolus day?1). Animals from CT presented a higher dry matter intake (9.54 kg day?1) than those from IT10 (8.63 kg day?1). Steers from CT and IT5 showed a higher NDF intake (3.63 and 3.58 kg NDF day?1, respectively) when compared to IT10 (3.29 kg NDF day?1). The constant energy pattern increases feeding time and dry matter intake. The one of less vigorous growth increases the number of bolus ruminated per day, while the one of more vigorous growth increases idle time and chews per bolus and decreases the intake of neutral detergent fiber.

The objective of this meta-analysis was to evaluate the effects of weight loss or weight gain of beef cows during the second and/or third trimester of gestation on the postnatal performance of the progeny. The variation in cow weight during the gestational period was calculated to standardize the treatments, being them: severe loss (SL = cows that lost more than 10% of weight); moderate loss (ML = cows that lost from 0 to 10% of weight) and weight gain (WG = cows that gained weight). The intensity of the cow weight variation effect was calculated as the mean difference (MD) with a 95% confidence interval and heterogeneity determined using the Q test and the I2 statistic. A meta-analysis of random effects was conducted for each indicator separately with the means of the control and experimental groups. Calves from WG cows were higher for birth weight (P = 0.0094); weight adjusted to 205 days (P = 0.0127) and average daily gain during pre-weaning (P < 0.0001) in relation to calves from ML cows. The W205 of calves from SL cows was 11.6 kg lower than the progeny from ML cows. The post-weaning performance of the progeny tended (P = 0.0868) to be higher in the progeny of WG cows than ML ones. The weight gain of beef cows during gestation improves the pre- and post-weaning performance of the progeny, with more evident effects in the early months of life of the offspring.

The objective of this study was to evaluate the metabolic status of beef cows during the final third of gestation and thereafter until the end of the subsequent breeding season. The study was conducted using 30 beef cows, aged between 4 and 11 years, derived from crosses between Charolais and Nellore cattle. To assess the metabolic status of cows, we obtained measurements of body weight and condition (BW and BCS), and complemented these by analyzing the following blood metabolites: total proteins, globulins, albumin, glucose, cholesterol, and triglycerides. Assessments were performed at 95 days pre-calving, and again at 7, 21, 63, and 110 days post-calving. The experimental design was completely randomized with five collection periods and 30 repetitions (cows). The BW of cows was found to be highest at 110 days postpartum (489.1 kg), and loss of BW was observed between 21 and 63 days postpartum (-3.72 kg). The lowest BCS value was recorded after 63 days of lactation (2.85 points). With respect to blood metabolites, concentrations of total proteins were higher at 7 and 110 days postpartum relative to the levels recorded during gestation (8.3 and 8.3 vs. 7.7 g dL-1, respectively), whereas serum globulin levels were higher at 7, 21, and 110 days postpartum relative to those at gestation (5.2, 5.2, and 5.1 vs. 4.8 g dL -1, respectively). Compared with samples obtained during gestation, the highest levels of albumin (P < 0.05) were observed at 7, 63, and 110 days postpartum (3.1, 3.1, and 3.2 vs. 2.9 g dL-1, respectively). Serum glucose was higher during pregnancy and in the first week of lactation relative to the values recorded after 21 and 63 days of lactation (80.9 and 76.7 vs 71.5 and 72.3 mg dL-1, respectively). Moreover, cholesterol concentrations increased with the progression of lactation, with the highest value being recorded at 110 days postpartum (222.1 mg dL-1). Collectively, the findings of this study, indicate that Charolais × Nellore cows raised exclusively on native pasture mobilize body reserves, lose weight, and show a negative energy balance during the first weeks of lactation, with detrimental consequences for subsequent reproductive activity.