Performance, egg quality characteristics, serum parameters, blood minerals and bone mineralisation of laying chickens fed bone dust as calcium source

The study investigated the effect of dietary inclusion of bone dust as a calcium source on performance, egg quality characteristics, serum parameters, blood minerals and bone mineralisation of laying chickens. A total of 128 point of lay birds (1470-1550g) were allotted on a weight equalisation basis to four dietary treatments. Each treatment consists of four replicates having 8 birds per replicate. The diets were designated T1, T2, T3 and T4 in which T1 is the diet with dicalcium phosphate (DCP), T2 is the diet with bone meal, T3 is the diet with 50% bone dust and 50% DCP and T4 is the diet with 100% bone dust. The experiment lasted for eight weeks; laying performance and egg qualities (internal and external) were evaluated on a weekly basis. Serum parameters, blood minerals and bone mineralisation were carried out at the end of the study. Data collected were subjected to a one-way analysis of variance using Minitab statistical software (17.0) and significant means were separated using Tukey’s test. The inclusion of 50% and 100% dust resulted in increased (P<0.05) daily feed intake (DFI). The use of 100% bone dust in the diet of layers resulted in the highest (P<0.05) number of eggs laid (NEL) (293.00) and Hen-day egg production (HDEP) (118.33 %). Eggshell thickness (EST) was highest for layers fed T3 and T4 diets. The highest (P<0.05) albumin height (AH) (10.04 mm) and Haugh unit (Hu) (94.62 %) was observed for layers fed T4 diet. Layers fed T1 and T4 diets had higher (P<0.05) total protein and globulin than other treatments. Calcium and phosphorus content in blood was highest (P<0.05) for layers fed T1 diet. Bone calcium and phosphorus were highest (P<0.05) for layers fed the T3 diet but lowest for those fed the T1 diet. It was concluded that bone dust can be included in the diet of layers at 50 and 100% for better performance and egg quality without negative effects on blood and mineral composition.