Location: Environmentally Integrated Dairy Management Research
Title: What do we know about heat stress on grazed dairy heifers?Author
 |
KOHMANN, MARTA - University Of Wisconsin |
|
Jaramillo, David |
|
Submitted to: Forage Focus
Publication Type: Popular Publication Publication Acceptance Date: 11/1/2024 Publication Date: 12/1/2024 Citation: Kohmann, M., Jaramillo, D.M. 2024. What do we know about heat stress on grazed dairy heifers?. Forage Focus. Dec. 2024 issue. Interpretive Summary: Technical Abstract: The Midwestern USA is the largest dairy producing region in the country. Maintaining herd size of high-performing animals depends on how well we can develop replacement heifers, which is crucial for a successful business. Raising replacement dairy heifers on pasture can do just that: while animals are able to reach growth targets, they do so at significantly lower cost compared to heifers raised on feedlots. Although raising replacement heifers on pasture can be successful, many producers have expressed concerns over animals experiencing heat stress during the grazing season. In the Midwest, heat stress may be experienced from June through August or later, when temperature and humidity reach their greatest levels. So far, no studies have evaluated heat stress effects, management options, and trade-offs for grazing dairy heifers in the Midwestern continental climate. This means we need to collect more data on the benefits of shade to animal performance in the Midwest, while also measuring other responses associated with plant and soil parameters. And that is exactly what we plan to do: next growing season at Marshfield Research Station, we will evaluate how shade affects dairy heifers growth and development, pasture production, and soil parameters – in addition to other responses such as animal water intake and enteric methane production, both important parameters to evaluate sustainability of grazing systems. |