EI-Banna,, M., Ibrahim, S., EI-Shabrawy, H., EI- Sedfy, E. (2004). RELATIONSHIPS AMONG PLAN OF NUTRITION, WEIGHT GAIN, AGE AT PUBERTY AND REPRODUCTIVE PERFORMANCE IN BALAD! HEIFERS.. Journal of Animal and Poultry Production, 29(3), 1091-1102. doi: 10.21608/jappmu.2004.239057
M. K. EI-Banna,; S. A. Ibrahim; H. M. EI-Shabrawy; Enas R. EI- Sedfy. "RELATIONSHIPS AMONG PLAN OF NUTRITION, WEIGHT GAIN, AGE AT PUBERTY AND REPRODUCTIVE PERFORMANCE IN BALAD! HEIFERS.". Journal of Animal and Poultry Production, 29, 3, 2004, 1091-1102. doi: 10.21608/jappmu.2004.239057
EI-Banna,, M., Ibrahim, S., EI-Shabrawy, H., EI- Sedfy, E. (2004). 'RELATIONSHIPS AMONG PLAN OF NUTRITION, WEIGHT GAIN, AGE AT PUBERTY AND REPRODUCTIVE PERFORMANCE IN BALAD! HEIFERS.', Journal of Animal and Poultry Production, 29(3), pp. 1091-1102. doi: 10.21608/jappmu.2004.239057
EI-Banna,, M., Ibrahim, S., EI-Shabrawy, H., EI- Sedfy, E. RELATIONSHIPS AMONG PLAN OF NUTRITION, WEIGHT GAIN, AGE AT PUBERTY AND REPRODUCTIVE PERFORMANCE IN BALAD! HEIFERS.. Journal of Animal and Poultry Production, 2004; 29(3): 1091-1102. doi: 10.21608/jappmu.2004.239057
RELATIONSHIPS AMONG PLAN OF NUTRITION, WEIGHT GAIN, AGE AT PUBERTY AND REPRODUCTIVE PERFORMANCE IN BALAD! HEIFERS.
Animal Production Research Institute, Agricultural Research Center, Ministry of Agriculture, Egypt.
Abstract
Eighteen pre-pubertal Saladi heifers were used to determine the effects of varying feed level during pre- and post-puberty period on subsequent growth and reproduction. Heifers were randomly allotted to receive 80, 100 or 120% of National Research Council (NRC) requirements for energy, protein and dry matter intake until conception. Heifers were fed their respective diets in groups. Heifers were observed for estrous behavior. The average monthly weight gains during the experimental period differed among groups and were 16.2.20.88 and 22.5 kg for the heifers fed 80, tOO or 120% of the NRC requirements. respectively. Feeding heifers 80% of NRC requirements prolonged age at puberty and sexual maturity and caused lower second service conception rates. Average serum progesterone concentration as indicated by the area under progesterone curve over the second estrous cycle tended to be Significantly low in the low-fed group. The present results indicate that energy and protein intake offered during pre- and post pubertal period have an effective role on growth and ovarian activity in Saladi heifers.