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Over the last fifty years a decline in fertility in high yielding Holstein dairy cattle is observed
as well as a steady incline of the stillbirth rates during the last years is detectable, especially in
Holstein-Friesian heifers.
Both dystocia and stillbirth can be affected by several factors such as birth weight of the calf,
gender of the calf, parity, age and breed of the dam, season of calving, gestational/calving
length, and furthermore number of calves. Infections (e.g. BVD), insufficient placenta
development, metabolic disorders of the cow, and congenital malformations of the calf belong
to causes of stillbirth which are not related to calving difficulties.
This present study focus primarily on analysing the periparturient levels of progesterone (P4),
estradiol (E2) and pregnancy associated glycoprotein (PAG) to investigate the possible effects
of hormonal and pregnancy protein disturbances on the incidence of stillbirth in Holstein-
Friesian dairy cows.
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