Melatonin and farm animals: endogenous rhythms and exogenous applications

Area of Science:

• Veterinary Physiology
• Animal Endocrinology
• Chronobiology

Background:

• Farm animal studies enhance understanding of melatonin's role in physiology, reproduction, and pelage.
• Recent work focuses on melatonin's regulation of porcine reproduction, cervine cycles, and wool/cashmere production.

Purpose of the Study:

• To review recent findings on melatonin's role in regulating reproduction and pelage in domestic animals.
• To clarify discrepancies in previous melatonin research in domestic pigs.

Main Methods:

• Review of existing literature on melatonin's effects in farm animals.
• Analysis of studies on porcine reproduction, cervine endocrine and behavioral cycles, and wool/cashmere production.
• Examination of melatonin's influence on reproductive physiology and pelage development.

Main Results:

• Domestic pigs utilize circadian melatonin rhythms for photoperiodic information, contrary to earlier beliefs.
• Exogenous melatonin advances gilt puberty and may combat seasonal infertility in pigs.
• In utero melatonin/photoperiod treatments influence offspring reproductive physiology and pelage development in ruminants.

Conclusions:

• Melatonin plays a crucial role in regulating seasonal reproduction and pelage cycles in various farm species.
• Further research is needed to understand the hormonal factors, transient effects, and specific mechanisms of melatonin action.
• Investigating endogenous melatonin rhythms in sheep, fallow bucks, and pigs remains essential.