Prevalence of mammalian schistosomes in captive elephants of central India

Abstract

Captive Asian elephants are pivotal in wildlife conservation pertaining to patrolling of distance places and chemical immobilization of flagship species of protected forest areas. They are excellent swimmer and prefer water wallowing for keeping body cool during resting time while pickup water borne infections. Blood flukes are only unisexual and dimorphic trematodes transmit through water snails cercariae invade soft skin of the susceptible host and finally reach in the blood vessels where they become adult migrate in the haepato-trachial route. The female blood flukes shed spiny eggs forms granuloma followed by necrosis in the liver and small intestine. During health monitoring and disease diagnosis of captive elephants of tiger reserves of central India screened 51 captive elephants that revealed 35.2% occurrence of blood flukes. The prevalence of mammalian schistosomes (Bivitellobilharzia nairi) eggs were recorded highest in the elephants of Satpura tiger reserve (67.0 %) followed by Kanha tiger reserve (46.6%), Bandhavgarh tiger reserve (33.3%) and Pench tiger reserve (25.0%) whereas lowest infection was encountered in Panna tiger reserve (14.2%). Remarkable decrease in haemoglobin (7.5-11.8, 10.06±1.47 g/dl), elevated aspertate aminotransferase (AST=65-102 85±21.6 U/L), alanine aminotransferase (ALT=85-105 91±17.4 U/L) and blood urea nitrogen (BUN=46.2-65.5 58.2±13.7 mg/dl) were observed as compare to elephants found negative for eggs of blood flukes. Infected animals showed clinical manifestations characterized as dullness and depression with emaciated body condition specifically in elephants those harbor higher EPG (> 1200-2300 egg/g) counts of B. nairi eggs.