Effects of sub-lethal concentrations of NPK (15:15:15) fertilizer on growth and feed utilization by the toothed carp <i>Aphyosemion gairdneri</i> under laboratory conditions

Progression of African CatfishClarias gariepinus(Burchell) early stages challenged with two common pond fertilizers in incubation media

“…The parameters may also have had an indirect influence by moderating or aggravating the toxicity of heavy metals (Cleveland, Little, Hamilton, Buckler, & Hunn, 1986;EPA, 1980;Nguyen et al, 1999;Price, 2013;Sauter et al, 1976;Weiling, Lin, Xuancheng, & Shuchun, 1991) on early-stage indicators. When the effect of hardness is examined in isolation (Molokwu & Okpokwasili, 2002;Silva et al, 2003;Ofor & Udeh, 2012) This is important because fertilizers are also toxic to other life stages (fingerlings and juveniles) of fish (Divya & Belagali, 2012;Omoregie, 2009;Omoregie, Ajima, & Keke, 2003).…”

“…Cognizance should be taken of the association between physico‐chemical parameters of the solutions and indicators of early stage of C. gariepinus when the fertilizers are to be used in pond fertilization, to mitigate their toxic effect on fish eggs and other components of pond biota. This is important because fertilizers are also toxic to other life stages (fingerlings and juveniles) of fish (Divya & Belagali, ; Omoregie, ; Omoregie, Ajima, & Keke, ).…”

Biochemical and haematological responses in African catfishClarias gariepinusfollowing chronic exposure to NPK (15:15:15) fertiliser

“…The toxic effect of some constituents of inorganic fertiliser has been reported by many authors (Ufodike and Onusiriuka 1990;Chukwu et al 2009;Capkin et al 2010;Sangeetha et al 2011). Omoregie et al (2003Omoregie et al ( , 2009) noted a reduction in growth, abnormal behaviour and mortality in toothed carp Aphyosemion gairdneri exposed to sublethal concentrations of NPK (15:15:15) fertiliser and alteration in the activities of lactate dehydrogenase and alcohol dehydrogenase in the liver of O. niloticus as a result of a single exposure to superphosphate fertiliser. Sublethal concentrations of toxic pollutants may affect the behaviour of organisms; the disruption of behaviour may reduce the fitness of the natural population, and may also inhibit the activity of some enzymes in fish, causing reduction in some growth parameter values.…”