Swine fertility in a changing climate

Area of Science:

• Animal Science
• Environmental Science
• Reproductive Biology

Background:

• Climate change is increasing global temperatures and weather extremes.
• Environmental hazards linked to climate change can negatively impact pig production and reproductive fertility.
• Sub-populations of pigs exhibit reduced fertility during summer due to heat stress.

Purpose of the Study:

• To assess environmental measures linking pig fertility to climate change.
• To understand the risks and develop solutions for heat stress impacts on pig reproduction.
• To investigate the relationship between rising temperatures and pig fertility metrics.

Main Methods:

• Analysis of pig fertility data in relation to temperature changes and heat stress days.
• Evaluation of physiological, behavioral, and feed intake changes in pigs under heat stress.
• Consideration of factors like climate, year, genotype, and management in fertility assessments.

Main Results:

• Elevated temperatures and heat stress days alter pig physiology, behavior, and feed intake, potentially affecting follicle development, oocyte quality, conception, and litter size.
• Boar sperm quality and production decrease with summer heat stress.
• Despite global temperature increases from 1999-2020, some regions showed improved female fertility (farrowing rate, litter size), possibly due to regional climate buffering or culling of susceptible females.

Conclusions:

• Pig fertility is influenced by a complex interplay of climate, genetics, and management practices.
• While fertility reductions are not universally apparent, widespread temperature increases are expected to make impacts more detectable.
• Proactive environmental management strategies are crucial for mitigating climate change effects on pig production and fertility.