Last update: November 22, 2010 12:01:19 PM E-mail Print

 

CASHMERE PRODUCTION BY A BOER GOAT HERD IN SOUTH AFRICA


 A. Theunissen¹#, J. A. Roux² & M. A. Snyman³


¹Vaalharts Research Station, Private Bag X9, Jan Kempdorp, 8550

²Cradock Experimental Station, P.O. Box 284, Cradock, 5880

³Grootfontein ADI, Private Bag X529, Middelburg (EC), 5900

 


A project, which involved the selection of Boer goats for cashmere production, was initiated in 1995 at the Koopmansfontein Experimental Station near Barkly West in the Northern Cape province of South Africa. The aim of the project was to select for a higher cashmere yield, without sacrificing body weight and to still conform to the breed standards set for the South African Boer goat. Selection during the first five to six years was limited to the buying of Boer goat bucks with cashmere potential from various Boer goat studs. Very little doe selection was practised, due to the fact that doe numbers had to be increased. The aim of this paper was to evaluate the cashmere production of the animals in this herd from 1996 to 2002.

Data were collected on the following cashmere traits during this period: combed greasy cashmere weight, combed scoured cashmere weight, clean cashmere percentage, down lengths on the shoulder, rib and britches, down mean fibre diameter, guard hair mean fibre diameter and down yield percentage. These data, collected on 81 bucks, 458 does and 373 kids, were analysed with GLM-procedures of SAS.

The average combed greasy cashmere weight for the bucks, does and kids (under one year) was 29.39±13.68, 30.66±19.52 and 17.09±8.04 g respectively. The down lengths on the shoulder, rib and britches were 36.90±8.51, 35.31±8.71 and 38.40±7.28 mm for the bucks, 29.50±10.86, 28.30±10.57 and 31.66±9.58 mm for the does and 28.0±7.88, 26.65±9.12 and 30.05±8.00 mm for the kids respectively. The mean fibre diameter of the down was 16.58±1.02, 18.02±1.19 and 15.42±0.81 micron, while the mean fibre diameter for the guard hair was 90.16±12.49, 78.44±16.96 and 83.07±9.51 micron for the three classes of animals respectively. The down yield percentage was 74.16±9.26 for the bucks, 81.13±9.81 for the does and 77.53±9.58 for the kids. The greasy cashmere weight, mean fibre diameter of the down and the guard hair of the male kids were lower (P<0.01) than that of the female kids.

Greasy cashmere weight had a significant correlation of 0.99 with scoured cashmere weight in all goats, while the correlations between greasy cashmere weight and the various down lengths varied from 0.38 to 0.56 and those between greasy cashmere weight and mean down fibre diameter from 0.15 to 0.27. Significant (P<0.05) correlations, ranging between 0.68 and 0.80 were estimated among the down lengths on the different body parts. No significant relationships between down length and down fibre diameter or down yield were found. Mean guard hair fibre diameter was negatively correlated with mean down fibre diameter in bucks (-0.52) and does (–0.51), but slightly positively correlated in the kids (0.13).

There was no significant (P>0.01) effect of age of the does (two to nine years of age) on greasy cashmere weight, scoured cashmere weight, down length, down and guard hair mean fibre diameter, clean fibre percentage or down yield. There was a significant (P<0.01) year effect on greasy and scoured cashmere weight and down length, but none on mean down fibre diameter.

The results indicated that the quantity of cashmere harvested from purebred Boer goats is low. Average mean down fibre diameter is also relatively high compared to those produced by traditional cashmere goats. However, there is a lot of variation among animals in the herd with regard to the various cashmere traits, which leaves scope for selection and possible genetic progress. Considering that the project has only been running for 7 years and that doe numbers had to be increased, very little selection of does was possible up till now. Stricter adherence to selection criteria (cashmere yield and down fibre diameter) should be followed to enable genetic progress. Genetic trends in the cashmere traits will be evaluated when more data become available.