TOLENTINO, L. H. O.; http://lattes.cnpq.br/6499753332259449; TOLENTINO, Laura Honório de Oliveira.
Résumé:
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.