This study aimed to assess preslaughter factors responsible for the occurrence of bruises to front, rib, loin, hip, and round sites of cattle carcasses. Data from the slaughter of 148 loads of cattle were assessed, totaling 4,611 carcasses. Evaluated bruising factor variables were animal gender, journey distance (km), vehicle type (m²), journey time (hours), load density (kg/m2), handling and facilities conditions (optimal, acceptable, and unacceptable), and unloading waiting time (min). Gender had the strongest influence on carcass bruising, being the first variable to enter in the majority of models related to the carcass sites. Female carcasses displayed higher bruising in all sites. Densities above 401 kg/m² caused more bruising. With the exception of the loin, unacceptable, and acceptable conditions assigned to farm facilities and handling resulted in higher average bruising. Articulated vehicles with a greater load capacity were more likely to cause bruising. The effects of variables causing bruises act differently in the various carcass sites. In this sense, the results of this study suggested possible management practices for specific problems during the preslaughter period to minimize losses by bruising to different carcass sites.

The objective of this study was to compare growth from birth to slaughter of different breed groups that were raised in Rio Grande do Sul, Brazil and estimate the consequent breed additive and heterosis effects. Caracu (C), Hereford (H), and Nelore (N) sires were mated with Angus (A) dams, and A sires were mated with H and N dams to produce a first generation of crossbred progeny that was contemporary with purebred A, H, and N calves. Heifers from this first generation (G1) were mated with Brangus (BN) and Braford (BO) sires to produce a second generation (G2) of progeny. Data were analyzed to estimate breed group means, individual and maternal breed additive effects, and heterosis effects on birth weight, weaning weight, preweaning average daily gain, yearling weight, postweaning average daily gain, fattening phase initial weight (around 19 mo), final weight (around 24 mo), average daily gain in the fattening phase, and age at slaughter. In general, crossbred calves outperformed purebred calves. Angus-N and CA crossbred cows weaned heavier calves. Individual taurine-indicine heterosis (Z) significantly increased weaning weight. The AN, NA, and CA steers were heaviest at yearling, whereas NA, CA, AN, and HA had the greatest final weights. However, AH steers were 1 mo older at slaughter than NA contemporaries. Taurine breed effects on postweaning traits and final weight were greater than for N. Maternal breed effects on birth weight and average daily gain in the fattening phase were greater for A and H than for N. In conclusion, heterosis effects were sufficiently large for use of N to be recommended as a component of such systems, despite their relatively low-breed additive effects compared with taurine breeds. Moreover, germplasm from the tropically adapted Bos taurus C may be particularly useful when increased milk production is desired. With the breed and heterosis effects derived in the present study, it is possible to predict the performance and infer which breed and breed crosses will perform better in crossbreeding systems designed for the subtropical conditions of southern Brazil and similar regions.

The objective of this study was to determine breed additive and heterosis effects on growth curves, total milk yield (TMY), calf weaning weight (WW), predicted energy intake (EI), and cow efficiency (CE) of purebred and crossbred beef cows raised in Southern Brazil. The data were from 175 purebred and crossbred cows representing eight genetic groups: Angus (A), Hereford (H), Nelore (N), A × H (AH), H × A (HA), A × N (AN), N × A (NA), and Caracu (C) × A (CA). Growth of the cows was modeled using the nonlinear Brody function and machine milking was used to assess TMY. WW was linearly adjusted to 210 d. EI was predicted with an equation in which the independent variables were estimates of parameters of the Brody function and TMY. The ratio of WW to EI estimated CE. Taurine–indicine heterosis effects were significant for all traits, and greater than those for taurine breed crosses. In general, crossbred cows were heavier at maturity, matured earlier, produced more milk, weaned heavier calves, and were predicted to consume more energy. Thus, they were more efficient than purebred cows, despite their greater predicted feed intake. Among the purebreds, A cows matured most rapidly, weighed the least at maturity, produced the most milk, weaned the heaviest calves, were predicted to consume the least energy; and were therefore most efficient among the breeds that were evaluated. These results are useful as inputs to bioeconomic models that can be used to predict productive and economic outcomes from crossbreeding and to facilitate recommendations for beef producers of southern Brazil and other similar subtropical climatic regions.

Assessment of carcass bruises in steers and cull females, classified during unloading at the slaughterhouse according to genetic dominance in zebu and taurine cattle, and the presence of horns, including polled, horned and mixed batches. We considered horned the batches that included more than 20% of horned animals and mixed the batches that included less than 20% horned animals. The data were collected in a commercial slaughterhouse and included 93 batches, with a total of 2,520 animals, from different regions in Rio Grande do Sul. After evisceration, the bruises were identified and recorded in the different carcass regions: hip, round, ribs, forequarter and loin area per animal and batch. The weights of the removed tissue due to bruising was based on the average weights of various samples of bruises according to their degree of severity. Regarding the number of bruises per animal, no differences (P > 0.05) were observed between genetic groups, however, when comparing the total bruises per batch, differences were observed in all carcass regions, except for the forequarter, with a greater number of injuries in zebu than in taurine carcasses. The individual assessments showed 86.2% (P < .05) more bruises in the ribs region in horned than in polled animals carcasses. Horned batches had higher bruises mean (P < .05) compared to the polled, with increases of 65.1; 131.7 e 132.8 % in total bruises in the carcass, ribs and forequarter, respectively. The mixed batches did not differ from polled and horned batches. Zebu animals were responsible for higher industry loss totaling 1.21 kg, resulting in a economic loss of R $ 15.48 per carcass. The presence of horns resulted in greater carcass loss, 1.13 kg, with economic loss of R $ 16.11 per carcass. The bruises on carcasses are affected by the breed group and presence of horns, with zebu and horned groups leading to greater economic losses for the meat production chain. Key words: Animal welfare. Carcass cuts. Taurine. Zebu. ResumoFoi realizado um estudo para avaliar as contusões na carcaça de machos castrados e fêmeas de descarte, classificados ao desembarque no frigorífico segundo a predominância genética em taurinos e zebuínos, e a presença de chifres, incluindo mochos, aspados e mistos. Foram considerados aspados os lotes que incluíam mais de 20% de animais aspados, e mistos menos de 20% de animais aspados. coletados em uma empresa frigorífica do RS, por intermédio da análise de 93 lotes, totalizando 2.520 animais, provenientes de diferentes regiões do estado. Após a evisceração, na linha de abate, foram identificadas as contusões e contabilizadas de acordo com as regiões da carcaça: quadril, traseiro, costela, dianteiro e lombo, por animal e total do lote. Os pesos dos tecidos removidos devido às contusões foi baseado nos pesos médios de várias amostragens das contusões de acordo com o grau de severidade das mesmas. Não houve diferenças (P > 0,05) no número de contusões por animal entre os grupos genéticos, porém, quando comparados os totais por lote, observ...

Objective Objective: The objective was to estimate economic values for production traits in a full life cycle system using a bio-economic model with Angus purebred and a terminal crossbreeding system with Nelore sires mated to Angus dams. Study Description Study Description: Phenotypic performance data were collected from the Bifequali crossbreeding scheme at the Embrapa Pecuária Sul Research Center of the Brazilian Agricultural Research Corporation. The data consisted of performance and carcass traits measured on progeny of Angus purebred and Nelore sires mated to Angus dams raised in a pasture-based production system from birth to slaughter (full life cycle). The economic characterization of the system was based on fixed costs and variable costs. The bioeconomic was developed in 'R' programming language using the phenotypic information and the production costs. To estimate economic values, the bio-economic model was first parameterized and a base profit was calculated. The Bottom Line The Bottom Line: The use of crossbreed animals provides an effective tool to improve important traits and system level profitability in a full life cycle beef production system.