Selected Ecto and Endo parasites found on Namibian hake, Merluccius species (Merluccius capensis and Merluccius paradoxus)

Abstract

Abstract by author:

Selected ecto and endo parasitic worms found in Namibian hake species, Merluccius capensis and Merluccius paradoxus were identified. Fish samples were obtained from the Namibian waters, from two trawling operations conducted at a depth of about 330m, at a position of 23°16'S; 13°22'E. Samples were randomly selected, frozen whole until the time of laboratory examination. Ecto parasites occurring on the skin and gills were determined and fish samples were opened from the anus to the pectoral girdle for helminthic endoparasites and from the coelomic cavity. Two common types of endoparasitic worms were found in the coelomic cavity. The most prominent and wide spread was a tightly coiled brownish cyst spread in the liver, stomach wall, gut or gonads, and subsequently identified as a larval nematode of the genus Anisdkis. Another endoparasitic helminth observed which was less frequent, was a cream coloured post larval stage of the trypanorhynch cestode Hepatoxylon trichuiri. This study shows lhat various parasitic worms infesting specific organs of Namibian hake species, Merluccuis capensis and Merluccuis paradoxus, directly depended on the size of the fish