Despite many challenges faced by animal producers, including environmental problems,
diseases, economic pressure, and feed availability, it is still predicted that animal production …

In dairy cows inseminated during the hot months of the year, there is a decrease in fertility.
Different factors contribute to this situation; the most important are a consequence of …

Summer heat stress (HS) is a major contributing factor in low fertility in lactating dairy cows
in hot environments. Although modern cooling systems are used in dairy farms, fertility …

Establishment and maintenance of pregnancy is difficult in lactating dairy cows exposed to
heat stress because of reductions in estrous detection rate and the proportion of …

When dairy cattle are subjected to heat stress, reproductive efficiency declines. Cows under
heat stress have reduced duration and intensity of estrus, altered follicular development, and …

Heat stress causes a large decline in pregnancy success per insemination during warm
times of the year. Improvements in fertility are possible by exploiting knowledge about how …

Heat stress causes large reductions in fertility in lactating dairy cows. The magnitude and
geographical extent of this problem is increasing because improvements in milk yield have …

Abstract In the Northern Hemisphere, from June to September and in the Southern
Hemisphere from December to March, there are periods of reduced fertility (sub-fertility) in …

The objective was to determine factors controlling seasonal variation in 90-d nonreturn rate
to first service (90-d NRR) including effects of location, milk yield, and weather variables on …

The production of embryos by superovulation is often reduced in periods of heat stress. The
associated reduction in the number of transferable embryos is due to reduced …