Last update: April 7, 2011 12:05:28 PM E-mail Print



MA Snyman & J.J. Olivier

Grootfontein Agricultural Development Institute, Middelburg, 5900

J.A.N. Cloete

Carnarvon Experimental Station, Carnarvon, 8925



Concepts like hardiness and adaptability are widely used by breed societies when promoting their breeds. Conservationists and breeders of indigenous livestock claimed that the indigenous breeds are exceptionally hardy and adaptable. Hardiness is defined as the ability to economically produce and reproduce under adverse environmental conditions. Evaluation of a breed's hardiness can therefore only be done under adverse or sub-optimum environments. At the Carnarvon Experimental Station in the North-western Karoo, Namaqua Afrikaner (indigenous fat-tailed breed), Afrino (composite white woolled mutton breed) and Dorper (composite mutton breed) flocks are maintained under similar management conditions. The experimental station is representative of the extensive low potential areas of the Karoo region. The natural pasture varies from mixed grass and shrub veld to karoo shrub veld and is described as arid karoo. The official grazing capacity norm is 5.5 ha per small stock unit. The climate is characterised through severe winters and hot summers. The average annual rainfall is 210mm and it occurs mainly during the autumn months. The total recorded rainfall from January 1992 to December 1992 was 98 mm, which was less than half of the average annual rainfall and resulted in very poor grazing conditions. Due to the deteriorating body condition of the Afrino and Dorper ewes, the Afrino ewes had to be supplemented with 300 g chocolate grain per day for a five month period from August 1992 until the lambs were weaned in the beginning of January 1993 (45 kg grain per ewe over that period). Dorper ewes each received 250 g of grain per day from the beginning of September 1992 for a four month period (30 kg grain per ewe over that period). It was not necessary to supplement the Namaqua ewes, probably due to their ability to mobilise their fat reserves. The resulting feeding cost per ewe was R54.00 for Afrino ewes, R36.00 for Dorper ewes and R0.00 for Namaqua ewes. The average weight of lamb weaned per ewe for the three breeds were 33.76 kg for Afrino ewes, 31.00 kg for Dorper ewes and 29.54 kg for Namaqua ewes. Taking a meat price of R10 per kg for Afrino and Dorper carcasses and R 8.00 per kg for Namaqua carcasses, together with dressing percentages of 46, 48.5 and 51.9 % respectively, income from lambs weaned were R155.02 for Afrino ewes, R150.35 for Dorper ewes and R122.65 for Namaqua ewes. The resulting income above feeding cost generated by the respective breeds were R101.02 per Afrino ewe, R114.35 per Dorper ewe and R122.65 per Namaqua ewe. During the subsequent lambing season, Namaqua ewes weaned 39.9 kg lamb, in comparison to the 38.9 kg and 32.0 kg of Afrino and Dorper ewes. The hardiness of the Namaqua Afrikaner was emphasized by the fact that in spite of receiving no supplementary feeding, the ewes still outproduced the other breeds in the subsequent lambing season. These results indicated that Namaqua ewes were able to produce more profitable under severe drought conditions than either Afrino or Dorper ewes.



Congress DAB-SASAS, Pilansberg, 1-4 October