International Journal of Aquaculture, 2017, Vol.7, No.5, 31
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altered mainly by changes in serum volume due to osmotic imbalances between extra- and intracellular
compartments induced by pathophysiological situations which also impair hepatic synthesis of blood proteins;
increase catabolism or losses of albumin in the urine and or promote synthesis of globulins by the
immunocompetent cells (McDonald and Milligan, 1992). In this study, dietary FB
1
induced hypoproteinamia in
the exposed
H. longifilis
catfish juvenile within the first 14 days and not after day 28 of the dietary exposure. This
may be attributable to a reduction in the feed uptake within the first 14 days and or subsequent adjustments to the
FB
1
amended diets starting from day 28 (Lemarie et al., 1991; Artacho et al., 2007).
Hypoproteinemia has been associated with malnutrition or malabsorption due to insufficient feed intake, digestion
or absorption (LeMerie et al., 1991; Artacho et al., 2007; McCue, 2010), hyperalbuminemia and
hyperglobulinemia on the other hand has been related to stress, inflammation or innate immune response in
teleostan fishes (Svobodova et al., 2001; Maita, 2007; McCue, 2010). In this study, hyperalbuminemia was
observed 7 days following dietary exposure of
H. longifilis
catfish juveniles to diets containing more than 40.0 mg
FB
1
/kg and not in fishes fed diets containing less than 20 mg FB
1
/kg; this was not observed at and after 28 days of
the feeding experiment, suggesting dietary FB1 at an inclusion rate greater than or equal to 20.0 mg FB
1
/ kg may
have produced an inflammatory condition in the exposed
H. longifilis
catfishes; similar to the reports in
Clarias
gariepinus
catfish juveniles exposed to dietary FB
1
, in which there was consistent leucocytosis at dietary inclusion
levels of FB1 ≥ 20.0 mg per kg diet (Adeyemo et al., 2016), and in Wistar rats feed diets containing fumonisin B1
(Voss et al., 1992).
Creatinine, a decomposition product of creatine and phosphocreatine; is an anhydride of creatine present in
muscles and released into blood following muscular injury or necrosis. Free creatinine is not metabolized in the
body and thus functions as a waste of creatine and excreted by the kidney. The serum concentration of creatinine
has been determined to be constant and directly proportional to the creatine content of muscles undergoing
degeneration and or necrosis. Because of its relative independence from such factors as protein intake, degree of
hydration and protein metabolism, Maita (2007), proposed its usage as a useful index for renal function. In this
study, there was a consistent elevation of serum creatinine concentration in fishes fed the FB
1
amended diets. An
increase in serum creatinine concentration has been reported to occur in any or a combination of conditions in
which blood urea is increased (Wagner and Congleton, 2004) or in conditions involving malfunctioning of the
kidneys and also in extensive muscular degeneration and or necrosis (McCue, 2010).
Urea, described to be quantitatively the most important non protein nitrogenous constituent of blood (McDonald
and Milligan, 1992) is the chief end product of protein metabolism excreted by the kidney. Its blood concentration
is reported to be directly related to the protein content of the diet and to the excretory capacity of the kidney
(Wagner and Congleton, 2004). In pathological conditions affecting the liver, urea formation is impacted resulting
either in an increase or a decrease in blood urea nitrogen. In teleostan fishes, the main product of nitrogen
metabolism is ammonia, and to a lesser degree, urea (Cnaani et al., 2004). Kidney conditions (principally nephritis
and or nephrosis) and urinary tract obstructions have been reported to be main aetiologies of increases in blood
urea nitrogen concentrations (Cnaani et al., 2004). Hence renal dysfunctions accompanied with severe renal
insufficiencies and or excessive bodily breakdown of proteins have been reported to be associated with elevations
of blood urea nitrogen concentration (Coz-Rakovac et al., 2005). The elevations of urea serum concentrations in
H.
longifilis
catfish juveniles seen in this study may represents impairments in the kidney functions of the fishes fed
diets amended with FB
1
similar to the findings in rats fed purified FB
1
(Voss et al., 1992).
The serum AST and ALT activities increased significantly in a dose and duration dependent manner compared
with to the fish fed the control diets. Increases in the AST and the ALT serum activity in the fishes fed the diets
amended with FB
1
is perhaps due to the hepatocellular injury and increased release of these enzymes (Tang and
Chen, 2003). Lactate dehydrogenase (LDH), has been reported to catalyse the conversion of lactate to pyruvate
under anaerobic conditions. An increase in the serum activity of LDH has been reported to indicate anaerobiosis
