Use of leukocyte subpopulations as predictive indicators of infectious processes in the transition period of high producing dairy cows in Argentinean herds.

SEBASTIÁN DEMYDA PEYRÁS; LEONARDO DE LUCA; MARIA ELENA DALLORSO

Lima

Congreso; XXII Congreso Panamericano de las Ciencias Veterinarias; 2010

Asociación Panamericana de Ciencias Veterinarias

Intramammary infections and placental retention are the two major pathological processes that occur in high producing dairy cows during transition period in both Argentine and worldwide herds, causing serious economic losses. The aim of this study was to evaluate the use of serum levels of the two major immune cell populations in cattle as predictive indicators of the possibility of occurrence of such infections in field trials on commercial herds in the Republic of Argentina Blood samples of 62 cows from two commercial dairy farms in the central region of Argentina were evaluated throughout their period of transition were collected at 14 and 7 days before birth, during birth and at 7 and 14 days after delivery. The values of total lymphocytes (LT) and the polymorphonuclear fraction (PMN) were determined individually for each sample using an automatic analyzer. Mediate clinical analysis determined the presentation of intramammary infection (mastitis) or retained placenta in each of the cases analyzed. The evolution of the variables was analyzed using an ANOVA procedure of two factors: stage of the transition period and health status. Significant differences were greater than 0.05 between serum levels of different groups of animals at the stage prior to delivery. Healthy cows show much higher values at the 7 days previous to deliver stage. Blood levels of LT and PMN can be used as predictive indicators of the occurrence of such diseases in the postpartum transition period in dairy cattle in field conditions.