Effects of dietary urea/energy on fertility in ruminants
By: Vivian GathDepartment of Animal Husbandry and Production
E-mail:Vivian.Gath@ucd.ie
Short description of research activities:
There has been a decrease in fertility of dairy cows over the last twenty years as their milk yield has increased. The modern cow is struggling to meet the metabolic and nutritional demands of the increased milk production. One of the important physiological effects of this stress is a decrease in fertility . An overall objective of our studies is to elucidate the mechanism by which fertility is compromised which may lead to an appropriate feeding and management strategy to restore optimum fertility.
Severe negative energy balance coupled
with raised plasma urea concentrations have been linked with reduced fertility
in dairy cows. Using ewes and beef heifers under strictly controlled feeding
management we can mimic the degree of negative energy balance and plasma
urea levels seen in dairy cows. Then using techniques such as embryo transfer,
embryo recovery, ultrasound guided transvaginal ovum aspiration, in-vitro
culture, embryo grading as well as hormone assays, we determine the various
effects of nutrition on the different stages of embryo production. The
results of this study will lead to the development of an appropriate feeding
and management strategy of high yielding dairy cows and also the early
identification of impending fertility problems in a herd. This would be
of great economic benefit to dairy farmers worldwide.
Contact : Vivian Gath,
Department of Animal Husbandry and Production
Faculty of Veterinary Medicine
Ballsbridge
Dublin 4
Ireland
Fax: 01-6600883
E-mail: Vivian.Gath@ucd.ie
Further information on Vivian Gath's work is available.