Bioscientifica Proceedings

Summary. Microbes commonly infect the female genital tract of cattle, causing uterine disease, abortion, and infertility. In particular, postpartum uterine disease develops in about 40% of dairy cows following infections with Gram-negative Escherichia coli and Gram-positive bacteria, such as Trueperella pyogenes. These infections damage tissues and cause inflammation in the endometrium, and perturb follicle growth and function in the ovar...

Summary. Mastitis has a deleterious effect on reproductive responses and fertility of dairy cows, which depends on whether it occurs before or after artificial insemination (AI). Subclinical intramammary infection (IMI) before AI reduced steroid concentrations in the preovulatory follicle of approximately one third of lactating cows, and was associated with low expression of major steroidogenic genes. Consequently, IMI induced an attenuated LH surge and delaye...

Summary. The increase of milk yield in dairy cows during the last decades has been accompanied by a reduction in fertility. This decline in reproductive performance is most likely caused by the pronounced negative energy balance typically observed in high yielding dairy cows and in cows suffering from production diseases. Often, both phenomena occur coincidentally. Cows with a profound negative energy balance and production diseases show hormonal alterations c...