ABSTRACT. The aim of this study was to evaluate the protein energetic, enzymatic and mineral profile of Nellore cows during the pregnancy, parturition and postpartum. Fifteen multiparous cows with 4 ± 1 years of age and live weight of 400 ± 50 kg were used at different stages (non-pregnant, in the initial, middle and late pregnancy, at birth, one day postpartum, 30 and 60 days postpartum). Blood collections were performed every 30 days and assayed for the following blood biomarkers: Protein (total proteins, albumin, urea and creatinine), energetic (cholesterol, triglycerides, glucose and beta hydroxybutyrate), mineral (calcium, phosphorus, magnesium) and enzymatic (alkaline phosphatase and aspartate aminotransferase). Calcium had the lowest concentrations (p < 0.05) in the initial pregnancy, while phosphorus had the highest concentration at parturition (p < 0.05). Triglycerides, glucose and beta hydroxybutyrate were influenced by the stages of pregnancy, reducing in the late pregnancy and at parturition. Glucose had a reduction in the late pregnancy and elevation in the postpartum. Beta hydroxybutyrate showed increase at the late pregnancy. Although lipomobilization occurred in the phases of higher metabolic demands in the attempt to maintain homeostatic conditions. Nellore cows did not present negative energy balance in the late pregnancy period, maintaining normal variation in blood markers throughout the experimental period.

ABSTRACT. This study was conducted to evaluate changes in hematological biomarkers of Nellore cows at different reproductive stages. Fifteen multiparous cows with 4 ± 1 years of age and live weight of 400 ± 50 kg were used at different stages (non-pregnant, in the initial, middle and late pregnancy, at birth, one day postpartum, 30 and 60 days postpartum). Blood collections were performed every 30 days and assayed for the following hematological biomarkers: hemogram (red blood cells, globular volume, hemoglobin, mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC)) and leukogram (total and differential counts). The erythrogram was influenced (p < 0.001) by the reproductive stages, with variation in the results obtained for the total red cell count, hemoglobin content, globular volume, MCV, MCHC and total plasma proteins. The reproductive stages influenced the leukocyte profile with variation in the total leukocyte count and in the absolute values of neutrophils, eosinophils, lymphocytes and monocytes. Hematological biomarkers of Nellore cows showed significant changes due to the physiological adjustments required in response to the metabolic requirements imposed in the final stage of pregnancy and in the beginning of lactation, ensuring the nutritional contribution in energy and oxygen transported through the blood.

RESUMO. Esse estudo foi realizado para avaliar o efeito da suplementação concentrada e das escalas de tempo de avaliação nas respostas fisiológicas e comportamentais de ovelhas prenhes em sistema de pastejo. Foi usando um arranjo fatorial 2 x 2 x 3 (duas raças: Morada e Santa Inês; dois níveis de suplementação concentrada: 0,5 e 1,5% do peso vivo; e três escalas de tempo de time avaliação: 10, 20 e 30 minutos) com seis repetições por tratamento. Os parâmetros fisiológicos foram influenciados tanto pelo período do dia como pela raça, com médias mais elevadas no período da tarde em ovelhas Santa Inês. Além disso, foi encontrada influência da suplementação concentrada entre as raças com superioridade em ovelhas da raça Santa Inês. A atividade de pastejo foi influenciada (p < 0,05) pelas escalas de tempo de avaliação. Intervalo de 10 minutos foi a metodologia mais eficaz para avaliar com maior precisão o comportamento desses animais. Ovelhas Morada Nova apresentaram menos tempo de pastejo (p < 0,05) na escala de 10 minutos em comparação com 20 e 30 minutos, que foram semelhantes (p > 0,05) para essa atividade. Assim, as ovelhas prenhes apresentaram alta capacidade adaptativa com observações de 10 minutos para uma melhor descrição da atividade de pastejo em Morada Nova.

ABSTRACT. This study was realized to evaluate the effect of concentrate supplementation and time scales of evaluation on behavioral and physiological responses of pregnant ewes on grazing system. The experimental design was a randomized 2 x 2 x 3 factorial arrangement (two breeds: Morada and Santa Inês; two concentrate supplementation levels: 0.5 and 1.5% of body weight; and three time scales of evaluation: 10, 20 and 30 minutes) with six replicates per treatment. The physiological parameters were influenced by period of the day and breeds, with higher values in the afternoon to Santa Inês ewes. Also, influence of concentrate supplementation was found between the breeds with greater values in Santa Inês ewes. But, it did not alter the physiological parameters among animals of the same genetic group. The grazing activity was influenced (p < 0.05) by the scales of observation intervals. Interval of 10 minutes was the most effective methodology to assess accurately the behavior of these animals due to higher number of the registries, offering higher data reliability. Morada Nova breed exhibited less time grazing (p < 0.05) on the 10-minute scale compared to 20 and 30 minutes, which were similar (p > 0.05) for such a feature. Thus, the pregnant ewes exhibited high adaptive capability with observations of 10 minutes for better description of grazing activity in Morada Nova.