Assessment of the nutritive value of toasted castor seed cake-based diets as a reflect on blood profile of weanling wistar albino rats

Résumé

Since the cost of feed is increasing due to the keen competition between humans and animals, there is a need to critically seek for a matching alternative. Castor seed cake, a residue after the extraction of oil from nutrients-rich castor seed constitutes a waste which can be converted into livestock feed. Thus, the study was carried out to investigate the effect of graded levels of castor seed cake diets on haematological and serum biochemical indices of weanling albino rats in an experiment that lasted 21 days. Thirty weanling Wistar albino rats were weighed individually and randomly assigned to 5 dietary treatments with 3 replicates of two rats in a completely randomized design. Diet 1 was a nitrogen-free diet (NFD), while diets 2, 3, 4, and 5 had 0% (without castor seed cake inclusion), 2, 4 and 6% castor seed cake replacing soyabean meal respectively. At day 21, blood samples were obtained from two rats per replicate for haematological and serum analysis. There were no significant differences (P>0.05) observed in all the parameters (packed cell volume, haemaglobin, red blood cell, white blood cell, lymphocyte, neutrophil, monocyte, eosinophil and platelet) measured. Similarly, diet had no effect on the serum biochemical indices (creatinine, urea, total protein and globulin) measured. Significant difference (P<0.05) was however observed in albumin (2.62 – 3.18g/dL) of rats on the different experimental diets. The albumin concentrations of weanling albino rats on dietary treatments were similar to those on the control diet but significantly (P<0.05) higher (3.09 – 3.18g/dL) than those on the nitrogen free diet. It can be concluded that castor seed cake can replace soyabean meal up to 6% inclusion level without eliciting detrimental effect on blood profile of weanling wistar albino rats.