Abstract:
Soybean meal is the main protein ingredient in poultry feeds. It is expensive, inadequate in supply and does not have sufficient β-carotene which gives the yellow yolk colour preferred by most consumers. Mulberry leaf meal (MLM) has been identified as a locally available alternative protein source in poultry feeds and contains β-carotene that may improve egg production and yolk colour. However, the optimal level of inclusion in layer diets is unknown and there is need for it to be determined. This study therefore determined the effects of inclusion of MLM as a protein source in indigenous chicken (IC) diets on feed intake, egg production and quality. Sixty, 29-week-old IC were used in this study. The Experimental diets contained 16% CP, calculated metabolizable energy of 2800kcal ME/KG and SBM was substituted by MLM at the following levels: 0% (Diet 1), 5% (Diet 2), 10% (Diet 3) and 15% (Diet 4). The chickens were offered the experimental diets for 8 weeks. Objective one determined the effects of inclusion of mulberry leaf meal in the diets on feed intake, feed conversion ratio (FCR), and egg laying percentage. Data on feed intake and egg production and FCR were collected daily. Feed conversion ratio data was calculated by dividing the weight of feed consumed by the weight of eggs produced. In objective two, a sample of five eggs per treatment were used to assess the external qualities (shape index, egg shell thickness and egg shell ratio). Objective three determined the internal egg qualities (yolk colour, index and yolk albumin ratio) and cholesterol content. Data collected was analyzed using generalized linear model (SAS, 2009). Mean separation was done using least significance difference at 5%. The results from experiment one showed that inclusion of MLM at 10% increased egg production, feed intake and decreased FCR. In experiment two, inclusion of MLM in the diets had no effect on external qualities except shell thickness that decreased. For objective three, inclusion of MLM in diets had no effect on internal qualities and cholesterol content except yolk colour intensity that increased to deep yellow. In conclusion, MLM should be incorporated at 10% in layer chicken diets to improve egg production and quality.
