Case of Nasitrema Sp. Eggs Detection in Captive Short-Finned Pilot Whale (Globicephala Macrorhynchus)

Abstract

The Nasitrema sp. parasitization in the short-finned pilot whale (Globicephala macrorhynchus) was detected using intravital diagnostic methods for the first time. The material for the study was excreted content of the upper respiratory tract which was voluntarily obtained from the whale ("blow" to the Petri dish at the trainer’s command). The study was conducted in May of 2016 at the Moskvarium – Center for Oceanography and Marine Biology. Two individuals of the short-finned pilot whale were captured in Taiji Bay (Japan) in the autumn of 2014 and transferred to Russia by air in January of 2016. The animals were kept at the temporary base in the Gerasimikha village, Pushkin district, Moscow region. Ovoscopy was performed using the native smear and Mikmed-5 light microscope (LOMO) in the light field. Yellowish eggs with caps at one of the poles were found in samples from one of the pilot whales. They were identified up to the genus (Nasitrema) according to their morphology and epizootic data. The life cycle of Nasitrema has not yet been revealed; however, being a Digenea, it, probably, must be heteroxenic. Therefore, an infected pilot whale is not a danger to other individuals.