Perfil bioquímico sérico, eletrolítico e hematológico de bovinos nelore criados em regime extensivo no Estado do Piauí.

Abstract

Cattle breeding is one of the agribusiness segments of relevant importance in the national economy. With the second largest cattle herd in the world, Brazil is among the leaders in animal protein exports distributing this commodity internationally to over 180 countries. Nelore cattle were widespread in the country, due to the prominence in the reproductive area and beef cattle. This breed has undergone intense genetic improvement in Brazil, being directed almost exclusively to meat production, which has contributed to national hegemony in the commercialization of animal protein. In the evaluation of animal health and welfare in addition to anamnesis and clinical examination, laboratory parameters are essential. Among these, hematological evaluation provides valuable information for assessing health status, as well as nutritional status and stress in cattle. It is also known that mineral, liver, kidney, muscle and metabolic diseases occur with considerable frequency in cattle. However, to assess changes in biochemical measurements related to the functioning of these systems, it is essential to establish normal values for different breeds and breeding conditions. Studies standardizing these reference values are still scarce in cattle from northeastern Brazil, specifically in the Cerrado. Thus, we aimed to establish the hematological, biochemical and serum electrolyte profile of Nellore matrices reared in extensive regime. Blood samples were collected from 55 healthy Nellore matrices for hematological, biochemical and electrolyte analysis. The average values of red blood cells (7.3x106/μL), as well as hemoglobin (12.16 g/dL), Mean Corpuscular Volume (48.52 fL), Mean Corpuscular Hemoglobin Concentration (33.5%) and Hematocrit (36.52%) presented small amplitude when estimating the reference ranges. Regarding the leukocyte series, the results obtained in absolute and relative values of both granulocyte and agranulocyte cells were close to the reference values found in other cattle. The results obtained in the composition of electrolytic, enzymatic, protein and metabolic profiles showed reference ranges similar to reference standards of other bovine breeds, but with reduced range of values. However, the measured levels of Calcium, Aspartate Aminotransferase and Total Proteins recorded reduced mean values. Therefore, it was concluded that the breeders present a slightly different biochemical and electrolyte profile pattern than other herds that can be justified by the applied nutritional management.