Studies on behavioural, blood metabolites and biochemical composition of Clarias gariepinus exposed to quarry particles

Abstract

In fish, exposure to pollutants can induce increase or decrease in haematological and biochemical composition. Haematology, biochemical and behavioural parameters of Clarias gariepinus exposed to quarry dust were examined. Quarry particles were collected and taken to the Department of Zoology and Environmental Biology, Olabisi Onabanjo University, Ago - Iwoye for sieving with tight perforated sieve to allow free passage of only the dust, then weighed for the experimental exposure. Two hundred C. gariepinus juveniles were obtained from Ministry of Agriculture fish farm, Ikenne, Remo, Ogun State at three weeks and six days of age and then acclimatized for 14 days at the Animal House. The fish were fed with commercial fish feed at 5% of their body weight twice daily. During the acclimatization, 80% of water in each tank was replaced daily. Quarry dust of 65 g, 150 g and 250 g were introduced in each allocated labeled tank. Behaviour of the fish species were observed and then sacrificed for the haematology study through recommended procedures. The fish size range between 579 and 590 cm in total length and 670 and 690 grams in total weight, while the average water temperature, pH, dissolved oxygen, electric conductivity and total dissolved solids was 28.0±0.1 ºC, 7.8±0.025, 3.05±1.3 ppm, 683.75±50 µscm-1 and 432.33±64 ppm respectively. Haematological parameters showed pack cell volume (PCV) and neutrophils to be significantly (P < 0.05) higher and white blood count (WBC) lower in the fish species. Meanwhile, lymphocyte, eosinophil, basophil and monocyte showed no significant difference in all the exposure. C. gariepinus blood biochemistry showed lower triglycerides level and higher cholesterol and high density lipoproteins, while levels of blood bilirubin, albumin, protein, urea, creatinine and alanine transaminase were higher. Thereby, quarry dust has harmful effects on fisheries and the findings shall serve as a baseline data for study other fish species.