Out of Season Breeding in Angora goats
By Dr Mackie Hobson BSc(Agric),BVSc

1. Reproduction

Angora goat’s natural peak breeding season is April-May. There are farmers who do start putting the rams in as early as mid-February to enable them to make maximum use of their lands during kidding.

The highest ovulation rates and goats showing heat in Angora goats is in autumn. Ewes matted at this time will perform at an optimal level. If rams were introduced out of season July-Sept when Angora ewes are normally in anoestrus will lead to very poor reproductive performance.

Melatonin is the day length measurer by which goats determine the season. Melatonin is manufactured by the pineal gland during the hours of darkness. As night duration lengthens more melatonin is secreted by the pineal gland and this signals the reproductive system to increase activity.

A drug Regulin (containing melatonin) can be used to mimick this effect. Regulin is in the form of an implant which slowly releases melatonin over an extended period. Melatonin marketed as "Regulin" (Gene Link Aust. Ltd) available in Australia.

Regulin used in a ‘normal’ breeding season may result in:

• Fewer non pregnant ewes
• More kids born per ewe
• A more concentrated mating/kidding (cannot be used to synchronise ewes)

Dosage: 1 implant (18mg) inserted subcutaneously 30-40 days before ram introduction. The implant is inserted s/c near the base of the ear.

Timing: It is expected mating and therefore kidding will occur over about 30 days with an early peak.

 A study by Diedericks,  King &  Coetzer  was conducted to evaluate the efficiency of melatonin implants to induce breeding activity in Angora goats during their anoestrous period (September-February). Eighty mature Angora does (> 35kg) were isolated from rams for a period of 2 months preceding the mating period (mid November).

The does were allocated at random to the control and melatonin treatment groups and kept separately for the duration of the experimental period.  Melatonin implants were administered subcutaneously to all rams and does in the experimental group four weeks prior to joining. The control does received no melatonin treatment.

Four per cent fertile rams were used in each group.

Results:

• A significant (P
• Kidding percentage (95 vs 52.5).

Results indicate that melatonin treatment could be a practical method to breed Angora goats outside their normal breeding season.

Reference:

EFFECT OF MELATONIN IMPLANTS* ON SEXUAL ACTIVITY OF ANGORA GOATS IN THE OFF-SEASON

 J.C. Diedericks, P.R. King & W.A. Coetzer1

 Grootfontein College of Agriculture, Middelburg CP,

1Dept. Animal Physiology, Stellenbosch University