Matt Lucy’s presentation began by defining the difference between stress and strain. Stresses are the external factors that impact animals. Strains are the animal’s response to those stresses. Stresses that might affect reproductive performance include heat and humidity, disease, and negative energy balance. The strains resulting from that stress might include elevated temperature, metabolic and hormonal imbalances, and reduced immune function. Each of those strains can affect the animal’s ability to become pregnant and stay pregnant. We are all familiar with the infertile eggs and embryos that follow heat stress. It is well documented that cows with health problems during the transition period are much less likely to become than cows without transition health problems. Strain can also interfere with ovarian function. Performance can be improved by reducing the stress or reducing the strain. If we use infectious disease as an example of stress, a cleaner environment and better ventilation can help reduce the stress. A vaccination program or a microbial that supports immune function might reduce the strain. A comprehensive program will address both stress and strain.
Impact of Stress and Strain on Reproductive Health of Dairy Cows; Matthew C. Lucy, University of Missouri, Columbia, MO; Dairy Cattle
Reproduction Cooncil Annual Meeting, Salt Lake City, Utah, November 14-16, 2023
Comments