TY - JOUR
T1 - The physiology of multifactorial problems limiting the establishment of pregnancy in dairy cattle
AU - Evans, Alexander C.O.
AU - Walsh, Siobhan W.
PY - 2012
Y1 - 2012
N2 - The failure of cows to successfully establish pregnancy after insemination is an important limiting factor for the efficiency of dairy production systems. The physiological reasons for this are many and pertain to the post partum and early pregnancy periods. Cows that suffer severe negative energy balance after parturition are prone to diseases (including uterine infection) that are, in part, explained by reduced function of the immune system, having negative consequences for subsequent fertility. In high-producing dairy cows, the duration and intensity of oestrus is low as a consequence of low circulating oestradiol concentrations, and after insemination, high embryo mortality is the single biggest factor reducing calving rates. Embryo mortality occurs as consequences of poor oocyte quality (probably caused by the adverse metabolic environment) and by poor maternal uterine environment (probably caused by carry-over effects of uterine infection and low circulating progesterone concentrations). Immediate improvements in the fertility of lactating cows on many farms can be achieved by applying existing knowledge, but longer-term sustained improvement will require additional knowledge in many areas including the physiology of the tissues that contribute to reproduction.
AB - The failure of cows to successfully establish pregnancy after insemination is an important limiting factor for the efficiency of dairy production systems. The physiological reasons for this are many and pertain to the post partum and early pregnancy periods. Cows that suffer severe negative energy balance after parturition are prone to diseases (including uterine infection) that are, in part, explained by reduced function of the immune system, having negative consequences for subsequent fertility. In high-producing dairy cows, the duration and intensity of oestrus is low as a consequence of low circulating oestradiol concentrations, and after insemination, high embryo mortality is the single biggest factor reducing calving rates. Embryo mortality occurs as consequences of poor oocyte quality (probably caused by the adverse metabolic environment) and by poor maternal uterine environment (probably caused by carry-over effects of uterine infection and low circulating progesterone concentrations). Immediate improvements in the fertility of lactating cows on many farms can be achieved by applying existing knowledge, but longer-term sustained improvement will require additional knowledge in many areas including the physiology of the tissues that contribute to reproduction.
KW - embryo loss
KW - fertility
KW - negative energy balance
KW - progesterone
UR - http://www.scopus.com/inward/record.url?scp=83155193559&partnerID=8YFLogxK
U2 - 10.1071/RD11912
DO - 10.1071/RD11912
M3 - Review article
C2 - 22394963
AN - SCOPUS:83155193559
VL - 24
SP - 233
EP - 237
JO - Reproduction, Fertility and Development
JF - Reproduction, Fertility and Development
SN - 1031-3613
IS - 1
ER -