International Journal of Aquaculture, 2016, Vol.6, No.15, 1
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and adapt to the diets/drugs even at higher level of inclusions and stimulate growth during the course of the trial.
This observation was similar to the reported increase / higher feed intake and enhanced digestibility of the dietary
components by the fish fed both tetracycline and furasol as dietary additives by Lawal et al. (2012).
Feed efficiency ratio (FER) and Protein efficiency ratio (PER) are used as quality indicators for fish diet and
amino acid balance (Shalaby et al., 2006). The PER values from this study was similar to reported increased PER
of
O. niloticus
fed varying levels of chloramphenicol as observed by Shalaby et al., 2006. Therefore the
C.
gariepinus
was able to utilize efficiently the protein in the diet adequately or the diet provided the needed quality
and quantity of protein for growth and health of the fish. The good overall growth performance of
C. gariepinus
fed AMX’s diets confirms the suitability of the chosen nutritional compositions for the fish. The feed conversion
(FCR) in the present study was higher than values (0.73 ±0.07 – 1.35 ±0.10) obtained by Lawal
et al., (2012), but
similar to values reported by Adewole (2016). Furthermore, these values were better than those reported by El-
Block (1975) that the FCR for
Clarias
ranged from 3.2 - 6.7, based on the quality of the feed. Furthermore, the
better FCR recorded by the fish fed amoxicillin compared to the control group is in agreement with Anderson et al.
(1999) who observed that the increase in nutrient uptake in broiler chickens consequently increased the growth of
the animal.
Condition is a term widely used to refer to the overall physiological status of health of an individual (Cone, 1989;
Stevenson and Woods, 2006) and it’s of central importance to many aspects of life history, including metabolism
(Oskarsson, 2008), reproductive potential (Oftedal, 2000) and mortality (Dutil and Lambert, 2000). The condition
factor in all the treatments reflected less than 1. Edward et al. (2010) expressed that a condition factor above 1
indicates better utilization of feeds by fish for growth and development. The result obtained in this study of less
than 1 may be attributed to the prolonged culture period (84 days), which may have been accompanied with
production stress.
Haematological profiles usually give vital information on the response of the body to injury, deprivation. Such an
evaluation is indispensably important in arriving at a diagnosis, making prognosis and also in the assessment of
efficacy of therapy and toxicity of drugs and chemical substances (Ihedioha et al., 2004). Therefore, the
heamatological parameters of
C. gariepinus
fed to different AMX’s diet revealed that the PCV, RBC and ESR
increased significantly within the tested diet, when compared to the control. The results obtained here were similar
to the reported increase in blood parameters of
O. niloticus
fed graded levels of chloramphenicol (Shalaby et al.,
2006) and Faisal (2003) reported the significant increase values of erythrocyte, haemoglobin and haematocrit of
the same catfish
C. gariepinus
at 1
st
and 3
rd
day after administration of ciprofloxacin, amoxicillin and ampicillin.
The red blood cell indices (MCV, MCH and MCHC) are particularly important for the diagnosis of anaemia in
most animals. This study showed a significant decrease of MCH, MCV in fish fed the highest level of Amoxicillin.
This is similar to the reported decreased in MCH and MCHC of
O. niloticus
fed the highest level of
chloramphenicol by Shalaby et al. (2006). These authors, therefore, assumed that decrease or increase of blood
indices may be attributed to a defense reaction against drugs and diets, which occurs by stimulation of
erythropoiesis.
The WBC counts in
C. gariepinus
fed different graded levels of amoxicillin diets decreased significantly when
compared to the control. The increase in WBC (leucopoena/lencopomia) observed in the fish fed the control diet
may be attributed to increase in production of leucocytes in the haemtopoietic tissues, such as kidney and spleen.
Lymphocytes are the most numerous cells comprising the leucocytes, which function in the production of
antibodies and chemical substances serving as defense against infection. The primary consequence of observed
changes in leucocyte counts in stressed fish is suppression of the immune system and increased susceptibility to
disease Wedemeyer and Wood (1974). Ahamefule et al. (2008) reported that decrease in number of WBC counts
below the normal range is an indication of allergic conditions, anaphylactic shock and certain parasitism or
presence of foreign body in circulating system. The values of WBC counts in this study were similar to (3 800
