International Journal of Aquaculture, 2017, Vol.7, No.1, 1
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Figure 4 Ovary histology of Nile tilapia fed different diets (A, control) without any supplementation , followed by three diets
supplemented with moringa leaves meal at 2, 4, 6 g kg
-1
diet (B, C, D, respectively) for 12 weeks. (A) There were few primary
follicles and multiple mature one in the parenchyma. Diets supplemented with moringa leaves meal (B, C, D) at different levels
exhibit multiple mature follicles associated with few primary as well as atretic follicles in the ovary. (H&E staining); scale bars = 40
µm
3 Discussion
Moringa leaves effects and their mechanisms of action have been widely studied in different animals. Established
reports of the healthful natural plant pointed out that moringa hold potential for animal and fish diet ingredients
(Yuangsoi and Masumoto, 2012). However, there is no information regarding the utilization of moringa leaves in
fish diets as feed additive. Certain plant derived protein sources have shown promise in order to substitute fish meal
in fish feeds. The replacement of moringa in conventional diets did not affect the growth performance of Nile tilapia
(
Oreochromis niloticus
) (Afuang et al., 2003; Richter et al., 2003). In this study, there were no significant
differences in terms of growth performance and feed efficiency (P > 0.05) among all treatments. This result may be
due to the fiber content of the plant-based diets which causes reduction of the nutrients reduces digestibility,
resulting in growth depression. These results agree with Afuang et al., 2003 who found that diets supplemented with
methanol-extracted moringa leaf meal containing 11, 22 and 33 g kg
-1
did not affect the growth of Nile tilapia
Oreochromis niloticus
. Using raw moringa leaf in the diets for tilapia showed that the fish meal protein replacement
at rate of 10% did not affect the growth performance (Richter et al., 2003). These results are in contrast with
(Karpagam and Krishnaveni, 2014) who found significant increase in weight and specific growth rate in
Oreochromis Mossambicus
fed
Moringa oleifera
leaves as growth promoter at 5% concentration supplemented feed.
In our study, the feed consumed was poorer in fish fed diets with moringa leaves meal. Ozovehe (2013) reported that
the depression in growth performance relates to decrease in feed consumed. The same results were found with
Afuang et al., 2003 who supposed that because of the comparative concentration of various anti-metabolic
constituents present in moringa leaves. No significant differences were observed in the whole body composition in
terms of moisture and protein (Table 3). The body lipid values were decreased and ash content increased with
increasing moringa leaves meal in the diets. El-Nadi and Khames (2015) found that the results of body composition
in terms of moisture, protein, lipid and ash content did not differ significantly except protein among all treatments
when fed diets contained different levels of moringa leaves (0, 5, 10 and 15 g/ kg). In the present study, there were
significant differences (P < 0.05) in lipid and ash content of fish body fed the experimental diets. Fish fed D4
exhibited the highest value (12.2) of ash content and the lowest value (16.3) of lipid content. The same results were
observed on Nile tilapia and common carp respectively when fish fed diets contained plant-based proteins
(Pouomogene et al., 1997; Siddhuraju and Becker, 2001; Afuang et al., 2003). The significant differences in blood
components of fish fed the experimental diets were observed (Table 4). Fish fed D3 exhibited the lowest value (6.2)
of total protein and glucose (35.3) of the blood. The lowest value (41.1) of the blood cholesterol was observed with
