Concentration of melatonin in plasma of goats treated with Regulin

Parry AL, Paterson DJ, Litherland AJ, Death AF, Staples LD
Proceedings of the New Zealand Society of Animal Production, Volume 50, pp 297-300, Jan 1990
Proceedings of the New Zealand Society of Animal Production, Volume 50, pp 297-300, Jan 1990
Article class: Conference Presentation
Subject Terms: Endocrine/autocrine/paracrine, Reproduction, Reproduction - female, Seasonality/photoperiod
Animal Type: Goat, Livestock, Production animal, Ruminant
Publisher: New Zealand Society of Animal ProductionAbstract
The duration of melatonin release from Regulin implants and the diurnal variation in plasma melatonin concentration was investigated in 18 cashmere wethers, divided into 3 treatments: C-control; T-treated with melatonin 18mg Regulin implant on 10.11.88; PT - previously treated with melatonin every 6 weeks for 10 months before receiving an implant on 10.11.88. Mean concentration of plasma melatonin in T remained high 52 pg/ml for up to 42 days after implant, then declined to 8.5 pg/ml at 50 days remaining relatively low for the rest of the sampling period. Goats from PT maintained much high concentration of plasma melatonin 226 pg/ml for 42 days after implant. Control goats showed very low mean concentration at 5 pg/ml. Between animal variation in plasma melatonin concentration was high coefficients of variation were between 100% and 200% within all treatments. At 8 days post-implant plasma melatonin concentration of goats in C showed a nocturnal increase averaging 12.5 pg/ml, between sunset and sunrise. The same diurnal fluctations were evident at 29 days post-implant. Goats in treatment T also showed a nocturnal rise in plasma melatonin concentrations with average increases of 15 and 24 pg/ml at 8 and 29 days post implant between sunset and sunrise. It can be concluded that the melatonin implants used in this trial lasted for 42 days after administration and a nocturnal rise in melatonin concentration was evident in control and treated goats.The whole of the literary matter of the Proceedings of the New Zealand Society of Animal Production is copyright New Zealand Society of Animal Production, Downloading this article signifies agreement with the terms and conditions of electronic access.
