Год выпуска: 2013 Автор: John Cassius Moreki Издательство: LAP Lambert Academic Publishing Страниц: 236 ISBN: 9783659446764
Описание
Calcium is the key element required for bone and eggshell formation in laying hens. Consequently, knowledge regarding the calcium requirements of broiler breeder pullets/hens during rearing period (up to 22 weeks) and laying period (23 to 60 weeks) is of utmost importance. This study showed that 1.0% Ca is adequate for normal bone development in broiler breeder pullets on restricted feed during rearing period. It seems that 2.5% Ca (3.5 – 4.0 Ca g/hen/day) is needed for growth, bone development and good egg quality of broiler breeder hens during the laying phase. From 23 to 35 weeks of age, 1.5% dietary Ca was sufficient to achieve maximum hen day production, egg weight and egg mass. Additionally, from 36 to 60 weeks of age 2.5% Ca is required for maximum hen day production, eggshell weight, egg mass and eggshell quality. Higher Ca retentions were observed for birds consuming 2.5% Ca diet compared to 1.5% Ca. Bone dimensions, mechanical properties, true cortical area and percent bone...
