Evaluation of fishmeal protein supplementation to commercial feeds for egg lay and quality in warm tropical region
AbstractA total of 140 Lohman pullets layers at eighteenth week of lay were randomly selected and used to study effects of graded levels of fishmeal protein supplementation to two commercial feeds (type A & B) on egg production and quality. Layers were divided into two equal groups each of which was divided into five equal sub groups of A1, A2, A3, A4, A5 and B1, B2, B3, B4, B5. Each feed type was used as control diet and also to formulate four other diets by supplementation with graded levels of fishmeal such that CP level of control diets (A1, B1) was raised from 16.0% to 17.0, 18.0, 19.0 and 20.0% respectively. Each sub group of layers (n=14) was fed particular treatment diet, at 120g/layer daily for 57 days. Eggs were collected daily for the last 50 days and samples were used to determine quantity by number, graded by weight and shape while egg quality was determined from shell thickness and yolk index. Irrespective of types of diets, layers consumed their ration. Those fed type A diets performed less than their contemporaries fed type B diets probably because of the latter's superior feed quality including balanced protein-energy ratio. Generally, fishmeal supplementation to the commercial feeds relatively improved egg lay and quality with optimum values recorded at CP level of 18.0%. Thereafter, increase in feed CP level relatively caused slight (sub groups A) or negligible (sub groups B) decline in egg lay and quality. Thus, control layers (A1, B1) laid 282 and 294 eggs at average weights of 56.9 and 60.3g and feed conversion values of 5.2 and 4.7 compared with egg numbers of 338 and 368 weighing 60.6 and 61.8g and feed conversion values of 4.1 and 3.7 (P<0.01) recorded for A3 and B3 sub groups respectively. There was significant difference between sub groups in their hen-day egg production rates and yolk indices (P<0.05). We recommend that for reasons of economics and higher profit margins, farmers who use commercial feeds in warm tropics should supplement feeds with fishmeal to CP levels not exceeding 18.0%.
KEY WORDS: Fishmeal, protein supplementation, egg quality
Nigerian Veterinary Journal Vol.24(2) 2003: 27-33