For More Prolific Sheep

Press, Volume CVIII, Issue 31754, 10 August 1968, Page 9

For More Prolific Sheep

A scheme for improving the prolifacacy of the New Zealand national sheep flock, and in particular the Romney, was put to this week’s conference of former Nuffield farming scholars by Mr F. C. Graham, of Turangi.

Mr Graham proposed the introduction to a quarantine station of four breeds from Britain—the Colbred with a lambing percentage of about 200 ,the Cadzow with a potential of about 260 per cent, the Landrace with genetic

capacity to produce litters of up to five lambs, and the Oldenburg with a lambing of about 200 per cent and clipping some 13 to 181 b of 445-46 s 46s wool—and then using Dorset Horn ewes and mating twice annually to speed the breeding of Scapie-free genetic material. There should also be established either by the Government, or preferably by an independent producer group, a proliferation farm at which would be gathered at least 2000 of the highest performing ewes available as recorded in the national recording scheme or by attested private recording, irrespective of breed. From this material would be developed Romney type improver rams rams that would blend reasonably into present flocks—for dispersal to approved breeders for incorporation into their flocks. “It seems to me that this is the quickest and most positive way to improve the lambing potential of the national flock,” said Mr Graham. Mr Graham said that breeders working to date on up to 1500 ewes had found the improvement to be too slow. The genetic base of most breeders and groups operating in New Zealand today was too low. Oscar Colburn, the British breeder, had emphasised that even on a highly prolific base less than 1000 ewes was just not enough. It was possible to breed a characteristic from one breed into another and breed out the undesirable traits that were in the associated animal reasonably quickly with twice

yearly lambing and litters 01 > three or four lambs. “The main requirement is ; to decide if we need this sori of genetic material and if sc to develop a sense of urgency in collecting it and propagating it “In 1965 it was freely agreed that a quarantine station that could be fully effective was a matter of national urgency and strong representations were made to the Minister of Agriculture by a number of persons, including myself, pointing out the threat that a Government-fav-oured British sheep industry armed with the sort of production potential I have mentioned could present to our trade . . . Somes Island as a playground for Wellington would serve us little if the British sheep men were given, by an attractive subsidy, the green light to produce. Current political trends in the United Kingdom seem to me to make this even more a distinct possibility.” In the discussion which followed it was obvious that the Oldenburg was favoured by several of the former Nuffield scholars as a means of upgrading the New Zealand flock, and In particular the Romney. One of these was Mr J. N. Tripe, of Wanganui, who said in a subsequent paper to the conference, that he was assured that it would be one of the original importations for the Somes Island maximum quarantine station. He said that what appealed to him was the simplicity of putting it across the national flock by artificial insemination and upgrading it to a 150 per cent lambing, with a minimum of disruption and without having to breed out the undesirable characteristics of other breeds. Two former Nuffield scholars from Canterbury, Messrs G. J. Slater, of Hilton, Geraldine, and P. G. Morrison, of Sheffield, also spoke in favour of the use of the Oldenburg in New Zealand, but Mr Graham considered that it would be too slow to affect ewes here in the way required. Some scholars, among them Mr D. K. Mackenzie, of Hinds, still maintained a regard for the possible improved performance of the Romney. He suggested that before a radical change in the structure of the industry was made they might do something about the breed that they had had for many years and he suggested an investigation into embryo losses. Later, when it was suggested that the Oldenburg was a German derivitive of the Romney and that the same strain might indeed exist in

New Zealand, Mr Mackenzie said that a breeder selecting for fertility had been able to achieve a 200 per cent lambing here, but Mr M. T. Bamford . (Masterton) said that few Romney breeders in Kent were getting more than 130 per cent and if a 150 per cent lambing was expected from Romneys “you might as well bash your head against a brick wall.” There was, however, Some feeling that in view of the time that would elapse before any imported material could be introduced into the national flock, home breeders should be making special efforts to uplift the level of prolificacy. The former Director-Gen-eral of Agriculture, Mr D. N. R. Webb, said that sheep might have to stay in the maximum quarantine station for four or five generations before they could be released.