Curvas de Crescimento de Bezerros da Raça Girolando / Growth curves of girolando calves / Curvas ce crecimento de becerros de la raza girolando

O cruzamento de zebuíno com taurino busca associar a rusticidade com produtividade, melhorando a adaptação de um animal de alta produção ao meio ambiente. O presente trabalho avaliou o crescimento e desenvolvimento em 338 bezerros da raça Girolando à desmama. As médias observadas em machos e fêmeas foram, respectivamente, para peso ao nascer 31,88±5,22 kg e 29,57±4,2 kg, para o peso a desmama 133,9±29,9 kg e 136,6±29,4 kg, para o perímetro torácico ao nascimento 72,47±4,12 cm e 70,62±3,62 cm e para o perímetro torácico à desmama foram 119,3±8,96 cm e 118±7,93 cm. Os machos da raça Girolando nasceram mais pesados e com maior perímetro torácico que as fêmeas. O peso e o perímetro torácico não diferiram (p≥0,05) na desmama entre machos e fêmeas. No presente trabalho, os bezerros da raça Girolando apresentaram padrão de crescimento e desenvolvimento compatíveis para serem criados em condições comerciais de exploração leiteira.

The mix of Bos taurus and Bos indicus is a breeding alternative to improve animal production, associated to the adaptation of the productivity with environment resistance. The present research evaluated the growth and development in 338 Girolando calves from birth until weaning. The average weight observed in male and female was respectively, at birth 31.88±5.22 kg and 29.57±4.2 kg; and the weight at weaning was 133.9±29.9 kg and 136.6±29.4 kg; for the thorax perimeter at birth, was 72.47±4.12 cm and 70.62±3.62 cm; the thorax perimeter at weaning was 119.3±8.96 cm and 118±7.93 cm. Girolando male calves were heavier and had a larger thorax perimeter than female at birth. The weight and thorax perimeter didn’t differ (p≥0.05) between males and females at weaning. In this study, Girolando calves presented satisfactory growth and development being able to be created in commercial conditions of milk explorations.

El cruce de los cebús con taurinos busca asociar el rústico con el productivo, mejorando la adaptación de un animal de alta producción al medio ambiente. La investigación evaluó el crecimiento y desarrollo de 338 becerros de la raza Girolando desde el nacimiento hasta el destete. Las medias observadas en machos y hembras, respectivamente, para el peso al nacer fueron 31,88±5,22 kg y 29,57±4,2 kg; para el peso al destete fueron 133,9±29,9 kg y 136,6±29,4 kg; para el perímetro torácico al nacimiento de 72,47±4,12 cm y 70,62±3,62 cm; perímetro del tórax al destete de 119,3±8,96 cm y 118±7,93 cm. El peso y el perímetro torácico no fueron diferentes (p≥0,05) al destete entre machos y hembras. En la actual investigación, los becerros de la raza Girolando presentaron padrón de crecimiento y desarrollo compatible para que sean criados en las condiciones comerciales de exploración lechera.

Follicle profile and plasma gonadotropin concentration in pubertal female ponies

Twelve female ponies were examined daily for 30 days and classified as ovulating (OV; N = 6; 197 ñ 6 kg) or prepubertal (PP; N = 6; 196 ñ 9 kg). Follicles were detected by ultrasound and gonadotropins quantified by radioimmunoassay. The mean diameter of the largest follicles was significantly larger in OV (38 ñ 1 mm) than in PP (26 ñ 2 mm) but there was no difference between groups in the size of the second largest follicle. There were more small follicles (<24 mm) in the PP than in the OV group, but PP fillies had a smaller number of follicles >29 mm than the OV fillies. Follicle-stimulating hormone (FSH) levels did not differ between groups but PP fillies had lower luteinizing hormone (LH) peak (8 ñ 1 ng/ml) and basal (4 ñ 0.5 ng/ml) levels, lower peak magnitude (2 ñ 0.2 ng/ml) and period average (5 ñ 0.6 ng/ml) than OV fillies (32 ñ 4.5, 8 ñ 1.2, 17.1 ñ 6, and 15 ñ 2.3 ng/ml, respectively). The PP group, in contrast to the OV group, showed no relationship between FSH surge and follicle wave emergence. We conclude that an LH concentration higher than 8 ng/ml is needed for follicle growth to a preovulatory size. Wave emergence and FSH secretion seem to be independent events, probably due to an inhibitory neural system in these PP animals. PP fillies may provide a physiological model for the study of follicle wave emergence which apparently does not depend on gonadotropin levels.

Plasma cortisol levels in captive wild felines after chemical restraint

Eight Panthera onca (Po), 13 Felis concolor (Fc), Felis yagouaroundi (Fy) 7 Felis tigrina (Ft) and 5 Felis pardalis (Fp) specimens from SÒo Paulo State zoos were used. All animals were restrained with darts containing 10 mg/kg ketamine and 1 mg/kg xylazine. Venous blood samples were collected as soon as possible (within 15-20 min) and serum was frozen until the time for cortisol quantification. Cortisol was determined using a solid phase radioimmunoassay with and intra-assay coefficient of 8.51 percent. Data were analyzed statistically by the Kruskal-Wallis test, followed by Dunn´s multiple comparisons test, and the one-sample t-test, with the level of significance set at P<0.05. Data are reported as means + SEM. Cortisol levels differed among the captive felines: Po = 166 + 33a, Fc = 670 + 118b, Fy = 480 + 83b, Ft = 237 + 42ab, Fp = 97 + 12a nmol/l (values followed by different superscript letters were significantly different (P<0.001). Since most of the veterinary procedures on these species involve chemical restraint, these results show the necessity of preventive measures in order to minimize the effect of restraint stress on more susceptible species.

Is the throughbred race-horse under chronic stress?

Thoroughbred fillies were divided into three groups according to age: group 1, 7 fillies aged 1 to 2 years (G1) starting the training program; group 2, 9 fillies aged 2 to 3 years (G2) in a full training program; group 3, 8 older fillies 3 to 4 years of age (G3) training and racing. Blood samples were collected weekly from July to December. Cortisol was quantified using a solid phase DPC kit. The intra- and interassay coefficients of variation were 12.5 percent and 15.65 percent and sensitivity was 1.9 + 0.2 nmol/1. The semester average of cortisol levels varied between groups: G1 = 148.8 + 6.7, G2 = 125.7 + 5.8, G3 = 101.1 + 5.44 nmol/l, with G3 differing statistically from the other groups. The lower cortisol levels observed in the older fillies leads us to propose that the stress stimulus, when maintained over a long period of time, may become chronic and result in a reduction of hypophyseal corticotropin-releasing hormone receptors. The secretion of endogenous opioids may also lead to low serum cortisol levels.