Biochemical and hematological profile of Otaria flavescens in the reproductive colony of Cobquecura, central-south Chile

Despite the ecological importance of the common sea lion Otaria flavescens, there is currently no information available on the blood chemistry and hematology of this species. Here, we report for the first time, 14 blood chemistry variables of O. flavescens and differential blood cell counts obtained from 15 resident individuals from a reproductive colony located in Cobquecura on the coast of central-south Chile, during 2 sampling periods, in 2009 and 2011. There was a high degree of biochemical regularity in studied parameters, although the plasmatic concentration of calcium differed significantly between genders; average concentrations of total proteins, globulins, cholesterol, and cholinesterase activity varied significantly between sampling periods. In comparison with the biochemical profiles reported for other marine mammals, O. flavescens had greater concentrations of globulins; an inhibitory capacity of antiproteases (close to 100%); and moderate to low cholinesterase activity and similar concentrations of glucose. Finally, differential blood cells counts indicated moderate to high eosinophilia (8.3-17.6%) in individuals sampled during the first sampling period, which suggests the possible presence of parasitism within this population. These results could be useful for assessing the state of health of O. flavescens populations and, therefore, contribute to species conservation in the Southeast Pacific. A pesar de la importancia ecológica del lobo marino común Otaria flavescens, existe escasa información referente a su química sanguínea y hematología, los cuales pueden ser utilizados para evaluar el estado de salud de las poblaciones. El presente trabajo, reporta por primera vez la determinación de 14 parámetros químicos sanguíneos de O. flavescens y su fórmula leucocitaria obtenida desde 15 individuos pertenecientes a una colonia reproductiva localizada en Cobquecura, zona centro-sur de Chile, durante 2 muestreos realizados, 2009 y 2011. Los resultados indican que existe una alta regularidad bioquímica para los parámetros estudiados. No obstante, se presentan diferencias significativas en la concentración plasmática de calcio entre ambos sexos y entre las concentraciones promedio de proteínas totales, globulinas, colesterol y actividad de colinesterasa de los 2 muestreos estudiados. Comparado con otros perfiles bioquímicos reportados para mamíferos marinos, en esta especie se determinó una alta concentración de globulinas y capacidad inhibitoria de a