Out-of-Season Breeding Artificial Lighting and Melatonin

Artificial Lighting and Melatonin

Photo of kid nursing dam.

Light treatment to alter photoperiod response is a well-known synchronization and/or induction method for out-of-season breeding in the dairy goat industry. Artificial lighting is mostly employed for long day simulation, administered as 16 hours of daylight followed by eight hours of darkness. To simulate long days it is not necessary to provide the entire 16-hour light period, but treatment can be divided into the natural daylight period followed by an appropriately …

Season Impacts Reproduction Influence of Daylength

Influence of Daylength

Doe with kid on pasture.

The environmental cue most dominantly affecting seasonal breeding in small ruminants is the annual change in day length (goats are considered short day breeders). Seasonal anestrous occurs when the day length increases and this period is associated with an absence of estrus and ovulation and decreased secretion of the reproductive hormones. Seasonal species are responsive to a hormone called melatonin which is produced by the pineal gland in response to declining periods …