Jatropha curcas
L. is a multipurpose shrub plant that grows wildly in the tropics and
subtropics. The nutritional value of Jatropha seed cake (JSC), a by-product of
Jatropha
curcas seeds, compares favourably with conventional seed meals with a crude protein
content of 58-64% and higher essential amino acids (excluding lysine) than soybean
meal. However, the presence of anti-nutrients restricts the use of Jatropha seeds in poultry
feeding. If properly detoxified, JSC can be utilised in livestock feeding. The
detoxification and reuse of this seed cake are vital for adding economic value and also
to reduce the potential environmental damage that may be caused by improper
disposal of this by-product. The study was carried out to investigate the effect of heat-treated
Jatropha seed cake on haematological and some serum biochemical parameters
of growing Japanese quails. Diet 1 was a corn-soybean meal (basal diet) with no Jatropha
seed cake (JSC). Diets 2, 3, 4 and 5 contained the basal diet and 5, 10, 15 and 20% JSC
inclusion respectively, in a completely randomised design. Two hundred 14-day–old
Japanese quails were grouped, weighed and randomly assigned to five treatments with
five replicates of eight birds each in an experiment that lasted for two weeks. On day 28,
blood samples were collected from the jugular vein of two birds per replicate into vials
containing the anticoagulant ethylene diamine tetra-acetate (EDTA) for haematology and
blood without EDTA to obtain serum for analysis. Diets had no significant effect on the
haematological parameters of birds on the experimental diets except on the white blood
cell (WBC) counts. White blood cell counts of birds fed 10% JSC diet was significantly
(P < 0.05) higher than those fed 5% JSC diet but WBC counts of birds on both diets were
similar to birds on other dietary treatments. Total proteins of birds fed the control, 5%,
10% and 15% JSC diets were similar but significantly (P < 0.05) higher than those of
birds on 20% JSC diet. Serum urea, creatinine and aspartate aminotransferase (AST) of
birds on the experimental diets were identical but significantly (P < 0.05) lower than
those of birds on 20% JSC diet. Alanine aminotransferase (ALT) of birds on 15 and 20%
JSC diets were similar to those on the control diet. It is concluded that 10% heat-treated
jatropha seed cake could potentially be used in Japanese quail feeding because it reflects
the optimal physiological state of the birds compared to other diets.