Akademik Veri Yönetim Sistemi
18. INTERNATIONAL CONFERENCE ON AGRICULTURE, ANIMAL SCIENCE & RURAL DEVELOPMENT, Konya, Türkiye, 24 - 26 Ekim 2025, ss.140-142, (Özet Bildiri)
Heat stress is defined as a condition in which animals' physiological,
metabolic, and behavioral adaptation mechanisms fail due to exposure to
temperatures and humidity above their thermal comfort zone. Heat stress is one
of the most significant environmental factors affecting productivity in animal
husbandry and poses a critical problem in the livestock sector because it
negatively impacts animals' performance, health, and welfare, directly or
indirectly leading to difficulties in animal husbandry. Rising temperatures due
to global climate change have become an even more critical problem for husbandry
in regions within the Mediterranean climate zone, which includes Turkey. Recent
reports have predicted that global temperatures will increase by 0.25°C in the
last 10 years, and this increase could reach 1.9 to 8.5°C by 2100. Considering
this situation, it can be predicted that heat stress will increase
significantly, causing more serious challenges to sustainable animal husbandry.
Cattle are highly susceptible to heat stress due to
their high body mass and limited sweating capacity. Heat stress in cattle: It
is particularly common in hot and humid climates and limits cattle's ability to
regulate body temperature. It negatively impacts reproductive efficiency by
putting pressure on animals' physiology and overall performance. The
Heat-Humidity Index (THI) plays a critical role in determining the severity of
heat stress in cattle, and THI exceeding 72 has been associated with significant
decreases in reproductive performance.
In cattle farming, reproductive efficiency is crucial
for ensuring herd sustainability and, consequently, economic profit. However,
heat stress directly affects reproductive functions in both cow and bull,
leading to decreased pregnancy rates. In cow, heat stress causes adverse
effects such as hormonal imbalances, poor estrus behavior, delayed ovulation,
and decreased oocyte quality. Furthermore, increased intrauterine temperature
in cows resulting from heat stress negatively impacts embryo development, leading
to implantation failure and, consequently, early pregnancy loss. In bulls,
hyperthermia in the testicular tissue disrupts spermatogenesis, impairs sperm
quality, and increases abnormal sperm counts.
The aim of this study is to examine in detail the
effects of heat stress on cattle reproductive performance. The physiological
and cellular changes, hormonal disruptions, and resulting decreases in embryo
development and pregnancy rates resulting from exposure to heat stress in both
female and male cattle will be evaluated. Furthermore, strategies developed to
mitigate these adverse effects will be comprehensively discussed.