Performance and organ histopathology of growing Japanese quails (Coturnix coturnix japonica) fed heat treated jatropha seed cake substituted for soyabean meal

Abstract

The 14-day study investigated the effect of heat treated jatropha seed cake (JSC) on the performance characteristics and histopathological parameters of growing Japanese quails. Two hundred 2-week-old Japanese quails were weighed and randomly assigned to 5 treatments with 5 replicates of 8 birds each. Treatment 1 was the basal (corn-soyabean diet) with no Jatropha seed cake (JSC). Treatments 2, 3, 4 and 5 contained the basal diet and 5, 10, 15 and 20% JSC respectively. Weekly weight gain, feed intake and percentage mortality of birds were assessed. At day 28, liver and bursa of fabricius of two birds per replicate were harvested for histopathological examinations. The results showed that feed intake (FI) of birds decreased as the levels of JSC increased across the diets. Birds on the control diet had the highest FI (146.65g/b) while the birds fed 20% JSC diet had the least FI value (69.97g/b), though similar to those on 15% JSC diet. Weight gain of birds on the control diet and those on 5% JSC diet were significantly (P < 0.05) improved when compared to birds on other diets. A remarkable weight loss was observed in birds on 20% JSC diet. A similar trend was recorded in the feed conversion ratio (FCR) of birds on 20% JSC diet. However, birds fed with the control diet, 5, 10 and 15% JSC diets had identical FCR. There was no mortality recorded for birds on the control diet and those on 5% JSC diets, meanwhile 25% mortality was recorded for birds on 10% JSC while 70% and 90% mortality were observed in birds on 15% and 20% JSC respectively. The results of histopathological indices of birds on the experimental diets showed that higher inclusion levels of heat treated JSC had a negative effect on the liver and bursa of fabricius of the birds as compared to birds fed 5% JSC diet. Increased congestion of the portal vein, vascular degeneration and sinusoidal congestion of hepatocytes were observed on the liver while hyperemia, necrosis and distension of interfollicular septum by oedema, hemorrhage and fibrosis were observed in the bursa. Conclusively, 5% heat treated JSC dietary level was considered the safest level for growing Japanese quails as percentage mortality increased with increasing levels of JSC inclusion.