Influence of feeding different calcium levels in layers diet on the mineral content of the eggs and shells

Abstract

This study was conducted to determine the influence of feeding calcium levels in layers' diet on the mineral content of the eggs and shells. One hundred and twenty black Harco layers which were 42 weeks old were randomly assigned to four treatment groups designated as T₁, T₂, T₃ and T₄ in a completely randomized design. Each treatment consisted of three replicates 2 3 4 which had 10 birds each. The set of 10 hens were kept in each demarcation in an open-sided poultry house (deep litter) well-constructed with cages for egg collection. The calcium inclusion levels in the diets were: T₁ = 2.5 %, T₂ = 3.5 % (control), T₂ = 4.5 % and T₄ = 5.5%.  Daily routine practices such as feeding, cleaning, and environmental sanitation were carried out to ensure better results. Hygienic condition and routine management practices were also carried out during the experimental period. At the end of 12 weeks of study six eggs were collected per replicate (18 eggs per treatment) for the study of the mineral content of the egg and the calcium (Ca) and phosphorus (P) concentration of the eggshell. From the result obtained, the egg minerals were significantly (P<0.05) affected by the diets except the phosphorus and sodium (Na) content. Treatment 4 had a significantly higher level of calcium while the lowest was T₁. Furthermore, T₁ had the highest level of potassium (K) which was significantly different (P<0.05) from others while the lowest was T₄ . The calcium content of the egg shell was significantly (P<0.05) different amongst the treatment groups with T₁ having the highest level while T₄ had the lowest. The phosphorus content of the shell was also 4 significantly (P<0.05) affected across the treatment groups with T₁ having the highest level of phosphorus and the lowest in T₂. It was therefore concluded that increasing the level of 2 calcium up to 5.5% may favor dietary minerals and the nutrition of man who are the end users of egg since Ca plays a vital role in body metabolism.