Gilson de Mendonça

Morfologia, características da carcaça e componentes do peso vivo em borregos Corriedale e Ideal

The objective of this study was to compare Corriedale and Polwarth breeds as to morphologic and carcass characteristics, as well as, to evaluate liveweight and liveweight components variation. Forty wethers (castrated at 30 days of age), were used (19 Polwarth and 21 Corriedale), weaned at 70 days, and slaughtered with one year of age. Animals were raised under extensive native pasture conditions at Embrapa Pecuaria Sul - CPPSUL, Bage, RS. Laboratory measurements were carried out at the Animal Science Department of Universidade Federal de Pelotas, in Pelotas, RS. Corriedale breed showed higher values (P 0.05). Corriedale breed presented higher slaughtering weight and higher hot carcass weight. Polwarth showed lower cooling losses, both in weight and percentage (P 0.05). Corriedale wethers presented higher weight for feet and lungs and lower weight for internal fat. In relative values, Polwarth wethers showed higher proportion of liver and internal fat. It is concluded that morphological differences are observed only in live animals. Liveweight components showed quantitative and qualitative differences for both breeds.

Comportamento de bovinos de corte em pista de remate

This wok was aimed at characterizing the behavior of beef cattle at an auction ring. 1572 animals were computed. Of this total, 1317 animals were crossbred Bos taurus taurus x Bos taurus taurus and 255 were pure European breed Bos taurus taurus. The animals were evaluated at the auction track during the IV Calves and Heifers market, held at Pinheiro Machado, RS. Temperament was evaluated according to the attribution behavior scores of the animals reaction when they entered (EEP) and moved (EMP) in the auction track. Scores could assume values from 1 to 4, low scores indicate calm animals whereas high scores indicate highly resistant animals to enter into auction ring (EEP) or highly agitated animals (EMP). Average facial whorl location (RED) was registered for each group of animals based on individual scores. Data were analyzed through linear association test according to procedures freq (Cochran-Mantel-Haenzel test) and corr (Pearson) of statistical program SAS (1989). Crossbred animals showed higher scores values for EEP (1.57 x 1.18, P<0.05) and EMP (1.63 x 1.18, P<0.05) and facial whorl was located well above the eyes level compared to animals with predominance of European blood (3.27 x 2.48, P<0.001). Facial whorl location was positively correlated to EEP (r=0.48; P<0.0001) and to EMP (r=0.49; P<0.0001). Crossbred animals showed greater reactivity than European animals when managed in an auction ring. Facial whorl location may be an auxiliary tool to identify highly agitated or fearful animals. EMP could be used to identify animals with worse temperament.

Influência da castração e da idade de abate sobre as características subjetivas e instrumentais da carne de cordeiros Corriedale

The objective of this trial was to evaluate the effects of castration and slaughtering age on subjective and instrumental characteristics of meat from Corriedale lambs raised on native pasture. Sixty male lambs (30 castrated and 30 intact) slaughtered at 120, 210 and 360 days of age were used in this experiment. The Longissimus dorsi muscle was used for all meat evaluations and analysis. No significant castration ´ slaughtering age interaction was observed for the studied variables. A significant slaughtering age effect was found for meat fat thickness and marbling, which had lower scores in animals slaughtered at more advanced age as well as for all instrumental characteristics of the meat, mainly tenderness that was reduced in older lambs. However, a significant castration effect was observed only for meat color (brightness according to the CIELAB system). It can be concluded that meat quality from Corriedale lambs grazing native pasture was not affected by castration. Slaughtering age affected meat quality with lambs slaughtered at 120 days of age showing the best results.

Avaliação da época de nascimento sobre o desenvolvimento corporal e os rendimentos pós-abate de cordeiros da raça Texel

Forty-nine intact Texel lambs were used to evaluate the effects of different birth periods (August vs. November) on body development, body measurements and carcass characteristics. Animals were maintained in pasture and slaughtered in December for those born in August and April for those born in November at 129 and 164 days of age, respectively. Prior to slaughtering forage yield was estimated by the Botanal technique, which showed that animals born in August had access to better quality pasture. These lambs had greater retail and true carcass yields, hot and cold carcass weights, and carcass fat score and covering fat than those born in November. However, green viscera yield was higher in lambs born in November probably due to the observed differences in pasture nutritional conditions. It can be concluded that birth period affected carcass characteristics in the present trial.

Época de nascimento, genótipo e sexo de terneiros cruzas taurinos e zebuínos sobre o peso ao nascer, à desmama e eficiência individual de primíparas Hereford

The objective of the present study was to evaluate the effect of calving season, genotype and calf sex on the cows weaning individual efficiency ( percentual relationship between cow body weight and calf weaning weight), birth and weaning weight of calves. Forty-eight primiparous Hereford cows with approximate average age of 3 years and grazing only native pastures were used. Sixteen inseminated with one Red Angus bull (Bos taurus) and 32 with Nelore (Bos indicus). Effects studied were calf genotype (GENOT), Bos taurus x Bos taurus and Bos taurus x Bos indicus, calving season (EPOCN) concentrated in the Spring and subdivided into three periods: 1S (September), 2O (October) and 3N (November and December) and calf sex (SEXO). Milk production (PL) was included as co-variable. Ten measurements of milk production obtained by the indirect method, weighing the calf before and after suckling, and eleven measurements of cow and calf weights, were made at 21 day intervals. Effects with significant influence on PN were GENOT and SEXO (P<0.05). P205 was significantly affected by EPOCN, SEXO and PL (P<0.05). EI was significantly affected by EPOCN, SEXO and PL until 147 days (P<0.05). Calf genotype and sex affected their birth weight. Weaning weight and cow efficiency are affected by sex and and calving season, but not by calf genotype.

Produção de Leite em Primíparas de Bovinos Hereford e Desenvolvimento Ponderal de Terneiros Cruzas Taurinos e Zebuínos

The objective of this study was to evaluate milk production of primiparous beef cows and growth of calves of two genotypes from birth to weaning. Forty eight Hereford heifers with average age of 3 years grazing only native pastures were used. Sixteen cows were inseminated with Red Angus (Bos taurus) semen and 32 with Nelore (Bos indicus). Effects were calf genotype (GENOT) - Bos taurus x Bos taurus and Bos taurus x Bos indicus, calving season (EPOCN), concentrated in Spring and distributed over three periods: 1S (September), 2O (October) and 3N (November and December), and calf sex (SEXO). Ten measurements of milk production obtained by the indirect method, weighing the calf before and after suckling, were performed at 21 day intervals. Overall average milk production for the entire experimental period was 4.80 ± 0.09 kg/day. No significant differences were observed on milk production for all variables studied. Calf weight gain was significantly affected by EPOCN but not by GENOT or SEXO. It was concluded that milk production of beef cows, under extensive field conditions, was not affected by the GENOT, EPOCN and SEX. Calf growth depended on EPOCN.

Época de nascimento sobre a composição regional e tecidual da carcaça de cordeiros da raça Texel

The effect of alternative birth season on regional and tissue carcass composition of sheep was evaluated. Forty nine (49) Texel intact male lambs, born in two seasons (August and November), were kept under grazing and slaughtered with an average age of 129 and 164 days, respectively. Prior to slaughter forage production was measured using Botanal method. Lambs born in August had more favorable forage conditions, showing higher body weight and proportion in the majority of cuts, as well as lower proportion of shoulder and leg muscles showing higher adipose tissue content in the majority of carcass cuts. For lambs born in November, a higher muscle:fat and muscle:bone rate in shoulder and leg, as well as a higher ribcut muscle:fat rate. Nutritional conditions are responsible for differences in weights and cuts yields, as well as for the tissue carcass composition, in lambs maintained under grazing regime, making feasible the use of alternative birth periods to increase animal offer for slaughter.

COMPONENTES CORPORAIS EM OVINOS CORRIEDALE NÃO CASTRADOS, CASTRADOS E CRIPTORQUIDAS ABATIDOS EM DIFERENTES IDADES

O presente estudo objetivou verificar o efeito da castracao, da idade de abate e da interacao castracao x idade, assim como do peso corporal sobre os componentes corporais em ovinos Corriedale. Foram utilizados 57 animais criados em condicoes extensivas, alimentados com pastagens nativas, no municipio de Pedras Altas, Rio Grande do Sul, Brasil. Os cordeiros foram desmamados aos 120 dias de vida, sendo abatidos 21 animais aos 120 dias (sete nao castrados, sete castrados e sete criptorquidas induzidos), 18 abatidos aos 210 dias de idade (seis nao castrados, seis castrados e seis criptorquidas induzidos) e 18 abatidos aos 360 dias de idade (tres nao castrados, sete castrados e oito criptorquidas induzidos). Atraves da analise de variância dos dados verificou-se efeito da interacao castracao x idade de abate para os componentes corporais: penis em kg e porcentagem e para porcentagem de patas. Houve efeito da castracao para: testiculos em valores absolutos (kg) e em valores relativos (%). A idade de abate apresentou efeito significativo sobre: carcaca quente (%), cabeca (kg), patas (kg), pele (kg e %), visceras verdes (kg e %), pulmoes (kg e %), baco (kg e %), figado (kg e %), rins (kg), gordura pelvica (%) e bexiga (kg). O peso corporal evidenciou influencia significativa sobre: carcaca quente (kg e %), visceras verdes (kg e %), pele (kg e %), cabeca (kg e %), pulmoes (kg), figado (kg), coracao (kg e %), rins (kg), diafragma (kg) e baco (%). Conclui-se que houve efeito da castracao, da idade de abate e da interacao desses fatores, assim como do peso corporal sobre os componentes corporais em ovinos da raca Corriedale e que estes fatores devem ser considerados na uniformizacao e valorizacao para um entendimento da cadeia produtiva e comercial.