PREVALENCE OF BACTERIA AND NEMATODE PARASITES IN AFRICAN CATFISH Clarias gariepinus CULTURED IN SMALLHOLDER CONCRETE PONDS IN NIGERIA

Nigeria is leader in sub-Saharan aquaculture production but over 80% of the farms are smallholder fish farms. Culture systems and poor management practice of farmers encourages pathogen infections, mainly parasites. We therefore surveyed prevalence of bacteria and nematode parasites of African catfish (Clarias gariepinus) cultured in smallholder fish farms located in Enugu of south eastern Nigeria. A total of eighty (80) African catfish of weight range 200-280 g (average wt 240 g) were randomly collected from four randomly selected smallholder concrete pond farms within Enugu metropolis. The catfish were examined for prevalence of nematode parasites and bacterial pathogens. Examination covered the ecto and endoparasites. The catfish were dissected from the mouth to the esophagus down to anus and the entrails were individually separated. Endoparasites and bacteria were examined by swabbing and incubating the organisms in agar for 24 h-48 h. Gram staining and biochemical tests were carried out for identification of the bacteria. A total of 15 catfish were infested with nematode parasites Procamallanus laevioncus, 10 catfish were infested with protozoan parasites Ichthyophthirius multifiliis. The rest of the catfish harbored either of three types of bacteria species Flavobacterium, Streptococcus and Pseudomonas or together with Ichthyopthirius multifiliis. The prevalent rates of the bacteria were Streptococcus 33%, Flavobacterium 34% and Pseudomonas 33%. Protozoan parasite Ichthyopthirius multifiliis was endemic in the skin, nematode parasites were more endemic in the intestine while the bacteria were endemic in the fins, skin, internal organs and the gills.