Estrous Synchronization Artificial Lighting and Melatonin

Artificial Lighting and Melatonin

Photo of kid nursing


Because the length of the day determines breeding in goats, light treatment to alter this photoperiod response is a well-known method to help get a doe to come in heat for breeding during the non-breeding season, especially in the dairy goat industry. Artificial lighting is used to mimic a long day (16 hours of either sunlight or artificial light) followed by eight hours of darkness. Then, the does are exposed to 8 hours of day and 16 hours of dark.  It takes quite a long time to get the animals cycling using this protocol and a light-proof barn with adequate lighting is needed to house the goats. Time and housing constraints may be impractical for commercial meat goat producers.

Administration of melatonin (a hormone naturally produced in the body) to mimic a different day length may be an effective alternative to light treatment. The typical protocol includes giving melatonin orally or as an implant for three months. To enhance the effectiveness of a shorter light treatment, a combination treatment of light and melatonin might also be an option.

Use of any products in goats that is not labeled for goats must be done with the advice of your veterinarian.

For additional reading on more treatment options used for out-of-season breeding please follow the link below:

Keywords: light treatment, melatonin, out-of-season breeding, daylight

References: Whitley, N.C. and D. J. Jackson. 2004. An update on estrus synchronization in goats: a minor species. J. Anim. Sci. 82: E270-276E (Proceedings).