Avaliações zootécnicas e hematológicas de ovelhas suplementadas com cromo orgânico

AUTOR(ES)
DATA DE PUBLICAÇÃO

2010

RESUMO

Previous studies have proved the metabolic essentiality of and a greater demand for chromium in situations of stress. Based on these pieces of information, evaluating the effects of dietetic adding of this mineral in the performance and in the hematological variable of Santa Inês sheep breed subject to adverse environmental conditions and to gestational metabolic stress. For carrying out this study 26 multíparous female sheep were used. They were divided into the chrome treatment, which consisted in supplementing 1.5 mg animal per day -1 with organic chrome, and control. The animals were kept in semi-extensive system with access to Stargrass pasture (Cynodon nlefuensis) during the morning and taken to the corral in the afternoon. Their weight and body condition were checked after the overnight fast on days 28, 56, 84, 112, 140, 168 of the experimental period, considering as day zero the beginning of supplementation and of breeding season. The rates of prolificity and delivering were checked, being the latter determined 30 days after the day of mating. The weighing at birth of lambs was carried out up to 12 hours after delivery. Following the previous schedule, fecal samples were collected from the rectum, and blood samples were collected by venous puncture of the jugular using vacuum collection tubes with sodic EDTA. From these materials, counts of eggs per gram of feces were determined and hematocrit values, hemoglobin levels and the differential and total counting of leukocytes were obtained. The results were grouped so that they could provide the average to each gestational period (initial ? days 0 to 50); average ? days 51 to 100; final ? days 101 until delivering) and studied by analyzing the variation for checking the effects of treatment, from the gestational phase and the interaction between them. The live weight, the body condition of the females, lambs? weights at being born and the rates of prolificity and delivering were not influenced by the treatment. The increase of the live weight of the ones with reduction of the body condition of the animals was observed with the evolution of the gestation. The weight at being born has not differed between the sexes; however, it was inferior in the lambs born of double delivering. The chromium reduce the number of neutrophils. The number of leukocytes, linfocits and eosinophils, the levels of hemoglobin and the packed cell volume have been reduced with the evolution of the pregnancy. The neutrophils have been increase on the final phase. Chrome has not influenced the performance during the reproductive season and along the gestation period. It has, however, modified the profile of the white cells of the blood, reducing the counting of neutrophils. The phases of gestation have had a great influence in the hemogram due to the physiological adaptation needed for foetus development.

ASSUNTO(S)

ewes ovino - criação leucócitos ovelha - gestação hemoglobina pregnancy hemoglobin

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