Occurrence and prevalence of fish parasites and the interaction with water quality parameters in selected small water bodies in western Kenya

Abstract

Water quality and the environment greatly influence the existence and proliferation of parasites in the water and consequently, fish. This can have profound implications on aquaculture within the water bodies. Few studies have been conducted on parasite aggregations about the water quality in small water bodies in Kenya. This study assessed the suitability of selected Small Water Bodies (SWBs) for aquaculture as regards fish parasites by assessing the relationship between the occurrence and prevalence of parasites to water quality, water depth, land use, and shoreline habitat type. Standard protocols and procedures were used in the collection, analysis of water quality, and assessment of fish specimens for parasitology. White spot disease, (a parasite with economic significance) was in 4 of the 6 SWBs studied and had varying prevalence rates ranging between 10% to 20%. Clinostomum, a zoonotic parasite was also recorded in one of the SWBs sampled in this study. Additionally, the study realised some significant differences in the water quality from the various selected SWBs (p˂0.05), which could be a pointer to the noted diversities in the parasite communities. The findings of this study indicated that there was a strong positive correlation (r2 > 0.8) between some parasites (Ichthyopthirius multifiliis, Clinostomum spp., Procamallanus, and Camallanus) and some water quality parameters (temperature, turbidity, Soluble Reactive Phosphorous, Total Phosphorous, and Silicates). In light of the increase in focus on fisheries and aquaculture as key drivers of the blue economy and food and nutrition security, and as the country explores new frontiers for investment in aquaculture in SWBs, the water quality and consequent habitat features such as depth and land use, need to be addressed before investment.