Effects of melatonin and bromocryptine administration for Spanish goats. II. Effect of season on cashmere growth, yield and fiber characteristics of does

T. Wuliji, A. Litherland, A. L. Goetsch, T, Sahlu, R. Puchala, L. J. Dawson, and T. Gipson

Manipulation for spring breeding in Spanish goats could improve reproductive efficiency, kidding rate, and cashmere production. Therefore, 80 Spanish does were used to determine effect of melatonin treatment on cashmere fiber growth rate, length, and characteristics during spring breeding. Treatments control (C); melatonin implant (18 mg; Regulin, Schering Pty. Ltd., Australia) without (MI) and with bromocryptine (225 mg) implants (MIB) (Innovative Research of America, Sarasota, FL); and oral administration of melatonin (3 mg/day) (Sigma Chemical Co., St. Louis, MO) without (MO) or with bromocryptine (MOB). Results of this experiment suggest that melatonin administration for spring breeding is an effective means of increasing cashmere production from Spanish goats. Melatonin, given by oral or a slow release implant, increased fiber growth rate, fiber elongation, fiber diameter, and cashmere yield in spring months. These changes were accompanied by a delay in the initiation of fall growth, but this did not influence annual fleece weight. Manipulation of seasonal breeding in cashmere growing goats, such as Spanish, in the USA could both increase production of goat meat and extend the cashmere growth phase in spring.