Replacement value of poultry visceral offal meal for fish meal in layers' diets.
The effects of replacing imported fish meal (FM) with poultry visceral offal meal (PVOM) in the diets of 200 Isa Brown laying hens on their performance characteristics and economy of egg production during 22 to 38 weeks or age were examined. PVOM replaced FM on an equal protein basis at the graded levels or 1.18, 2.37, 3.55 and 4.73% of diet B,C,D, and E respectively. The control diet A contained 4% FM as the sole source of animal protein. All diets contained ca 16% crude protein while their calculated metabolisable energy was ca 2600 kcal/kg diet. Observations were made at intervals of 4 weeks and entire 16-week period. Neither feed intake nor egg weight was affected (P > 0.05) by dietary treatments during the 4, 28 day and entire 16-week periods. The results of feed intake: egg weight ratios on the respective diets for each 28-day period and entire study period showed significant differences (P < 0.05) and similarity in the values or this parameter between some dietary treatments but the effect of PVOM inclusion levels on this parameter did not follow any consistent trend to undermine the results of other parameters. Mean daily egg production was higher (P < 0.05) on diet A than on the rest diets during 22 to 26 weeks of age but these ditTerences gradually disappeared towards 38 weeks of age. Daily egg yields per 10 birds on diets D and E were similar but lower (P < 0.05) than on the rest diets whose egg yeilds were also similar for the entire 4 month period. 'The performance data for the 4·months period on mean daily feed intake (g/bird) stood at 78.81 (A), 80.32 (8), 85.31(C) 81.70(D) and 75.88(E) while the feed intake : egg weight ratios were 1.46(A), 1.51(B), 1.58(C), 1.52(D), and 1.41(E). Mean dally egg yields were 6.85, 6.88, 6.73, 6.25 and 6.14 for diets A,B,C,D and E respectively while mean (g) were 54.15(A), 53.23(8), 54,00(C) 53.75(D) and S3.88(E) for the same period. PVOM could not replace FM beyond 59.25% of its proportion in the control diet without detrimental effect on egg production, although higher inclusion levels of PVOM did not affect feed intake and egg size but could further reduce feed cost.
Keywords: Poultry visceral offal meal, fish meat, protein, layer, performance.