Jimena Laporta, assistant professor in the Department of Animal and Dairy Sciences, received $650,000 for her project “Targeting environmental and nutritional factors in early life to achieve optimal mammary growth and future productivity” through NIFA’s AFRI Animal Nutrition, Growth and Lactation Program. It was among 25 projects sharing $13 million in funding.

Project summary (from CRIS website): Stressful experiences during the first weeks or months of life, such as heat stress and malnutrition, can influence a cow’s ability to produce milk later in life. While most dairy producers around the globe understand the value of preventing heat stress in adult cows to limit the visible and immediate drop in milk production, interventions to mitigate heat stress are not common in young dairy calves. Furthermore, young dairy calves are typically fed limited amounts of milk twice daily for the first 6-8 weeks of life. Further reductions in milk intakes are exacerbated during hot summers, as calves involuntarily reduce feed intakes. It is becoming more evident that optimal management of young dairy calves can positively influence productive outcomes later in life. For example, we have shown that providing heat abatement to Holstein dairy calves in summer improves feed intakes and growth trajectories. Also, enhancing nutrition in dairy calves promotes mammary gland growth and development. Indeed, these management strategies applied independently can lead to greater milk output later in life. However, the potential synergetic effects of these interventions in programming mammary gland development and function potential are unexplored research areas and will be the focus of our research. The main goal of this proposal is to target practical management interventions during the first weeks of life to improve mammary gland growth and the future lactation performance of dairy cows. Specific objectives are to: 1) determine the individual and combined effects of heat stress abatement and nutritional plane on mammary gland development and first lactation milk production, 2) investigate the molecular and cellular mechanisms in the mammary gland by which these interventions might translate into long-lasting milk production improvements, and 3) to validate these findings in continental and subtropical summers across the U.S. We believe that increasing the plane of nutrition to Holstein dairy calves during the first weeks of life, combined with heat abatement in summer, will act synergistically, translating into long-lasting improvements in their growth, mammary development, and first lactation milk yield. This proposal will contribute to our understanding of fundamental concepts of mammary gland developmental programming in dairy ruminants and promote practical on-farm management strategies that can be implemented in early life to increase milk production in dairy cattle. Further, we will characterize the magnitude and direction of physiological and production responses to nutrition and heat abatement interventions in two climates across the U.S. With this, we will address a timely topic in the face of climate change, as more animals will be exposed to extended periods of elevated temperatures despite their geographic location.