HEIFER NUTRITION - PREPUBERTAL GROWTH AND DEVELOPMENT

Authors: Capuco, Anthony; ERDMAN, RICHARD - UNIVERSITY OF MARYLAND; DAHL, GEOFF - UNIVERSITY OF ILLINOIS; MEYER, MATT - CORNELL UNIVERSITY; VANAMBURGH, MICHAEL - CORNELL UNIVERSITY

Submitted to: Proceedings of the Maryland Nutrition Conference
Publication Type: Proceedings
Publication Acceptance Date: 4/27/2003
Publication Date: 4/27/2003
Citation: Capuco, A.V., Erdman, R., Dahl, G., Meyer, M., Vanamburgh, M. 2003. Heifer nutrition - prepubertal growth and development. Proceedings of the Maryland Nutrition Conference.

Interpretive Summary: Rapidly rearing dairy heifers before puberty can result in decreased milk production and increased calving difficulty. Data suggest that mammary gland growth is inhibited when excessive body fattening occurs. The mechanisms by which fattening prepubertally impacts milk production are uncertain but may be due to a reduction in the number of secretory cells during lactation, altered nutrient utilization, or reduced skeletal size. Factors that may impact the growth and development of stem cells within the mammary gland may be key to understanding mammary gland biology of replacement heifers and to improving production efficiency through direct effects on the mammary gland. Accelerated body growth in the absence of excessive fattening can be achieved with appropriate nutritional management to provide sufficient protein and energy for balanced growth. This can be aided by growth hormone supplementation. Such regimens can be used to achieve early calving, increased skeletal growth and maximal or near maximal milk production

Technical Abstract: Rapid rearing during the prepubertal period can result in decreased milk production and increased calving difficulty. Data suggest that mammary gland development is inhibited when excessive body fattening occurs. The mechanisms by which fattening prepubertally impacts milk production are uncertain but may be due to a reduction in the number of secretory epithelial cells during lactation, nutrient programming, or negative impact on body size. Factors that may impact development and proliferation of progenitor cells within the mammary gland may be key to understanding mammary gland biology of replacement heifers and to improving production efficiency through direct effects on the mammary gland. Accelerated body growth in the absence of excessive fattening can be achieved with appropriate nutritional management to provide sufficient protein and energy to ensure balanced growth. This can be aided by GH supplementation. Such regimens can be used to achieve early calving, maximal mammary development prepubertally, increased skeletal growth and maximal or near maximal milk production