Changes in weight
are used as a marker for checking animal health status, and the reduction in
body weight is used as an indicator worsening of experimental rats during the
experimental period (Brzoska et al. (2003).
In Figure 1, the significant (p<0.05) decrease in weight gain of the rats fed CPO-CCD when compare with the control may be associated with considerable tissue damage caused by crude oil contaminated diet toxicity, which is in line with the study of Fadairo and Otite-Douglas (2015). The authors stated that alterations in body weight gain are usually seen as toxicity indices and significant reduction in weight gain and organ body weight ratio in crude oil fed rabbits reveals the toxic nature of crude oil. The results of the study is also aligns with the works of Timbell (1991); Horiguchi et al., (1996), also the work of Asagba et al., (2007), who determined how Cd toxicity caused a significant reduction in male reproductive organs/ body weight ratio in rats. The progressive increase in body weight gain of rats fed CPO-CCD treated with MDEE having the highest weight gain followed by the treatment with MEE and MWE when compared with the CPO-CCD control, may likely indicates the ameliorating effects of the M. myristica extracts. The decrease observed in the liver weight of the rats given CPO-CCD only (Table 1) is in line with the results of previous study conducted by Eidi et al. (2012) who indicated that absolute organ weight decrease may be an indication of organ injury. In this study the no significant (p>0.05) difference in the relative and absolute
kidney weights of the rats may probably due to the short duration of feeding
the rats with the crude oil contaminated catfish diet. The relative brain weight was low
variably when compare to the relative liver weight and relative kidney weight,
this may be due to the fact that the brain is not considered to be affected or
influenced by nutritional factors (Long et
In Figure 2, the data obtained in the study revealed that there
was a reduction in the concentration of
the haematological parameters analyzed in rat fed crude oil contaminated diet. It is obvious
that rat fed crude oil catfish
contaminated diet caused a significant reduction (p<0.05) in RBC count, consequently, Hb and PCV also reduced significantly (p<0.05) as compared to the control. The observed reduction in the levels of RBC, Hb and PCV suggest an anaemic condition in rat fed crude oil contaminated diet. The significant reduction (p<0.05) in RBC count could be attributed to cytotoxic effect and suppression of erythropoiesis caused by constituents of the crude oil in the diet. This is in line with previous studies Achuba and Nwokogba (2015); Ita and Udofia (2011); Sunmonu and Oloyede (2007). Treatment with M. myristica extracts reversed the anaemic condition as evidenced by improvement of mean values of haemoglobin, RBC and PCV as compare to the control. The significant (P<0.05) increase observed in WBC of rats fed CPO-CCD in this study is similar to the findings of previous studies conducted by Dede et al. (2002), in which there was an increase in WBC of rats exposed to crude oil. This increase in WBC suggests induction of the immune system defensive mechanism during crude petroleum oil toxicity. Uboh et al. (2009) reported the effect of antioxidant vitamins A and E on petroleum product induced haematotoxicity and showed that antioxidant vitamins reduces haematotoxicity following exposure of rats to gasoline vapours. From the results of this study the extracts of M. myristica are rich in antioxidants (George et al., 2011) which may help in reduction of haematotoxicity. CONCLUSION It is possible to suggest that CPO-CCD induced ROS have been implicated as the mechanism of alteration of haematolical parameters which results to different heamatological abnormalities in function observed in this study. The administration of M. myristica extracts showed a significant renewal of the hematological parameters. This may be due to the antioxidant defense system of M. myristica extracts.