Hallowell, G.

Olivier, B.

Ramsay, K.

Swart, D.

CGSpace

339Ramsay et al.ICAR Technical Series - No 3The development of the Dorper sheep and the Improved Boer Goat areundoubtedly two of the most successful long-term livestock programmesin South Africa. The Dorper is a composite mutton sheep breed developedthrough crossing an indigenous breed with a British mutton breed andthe Improved Boer Goat was developed using a breeding strategy basedlargely on selection for fertility and meat production.Both breeds were developed for low input production environments andboth have subsequently been influenced by market preferences and trendsas well as ‘fancy points’ that often have no bearing on adaptive orproduction traits.Both breeds were also part of Government-assisted programmes and bothbenefited from the establishment of a breed society and a national recordingand evaluation scheme.This paper reviews the strategies put into place to develop the Dorpersheep and the Improved Boer Goat and discusses aspects that have beenimproved and could have been improved upon.The main objective of the Dorper programme was to develop a hardymeat-producing sheep for the extensive production areas of the country.The breed was developed by crossing Dorset Horn sheep with thefat-rumped black headed Persian sheep, a local Somali sheep variety.A major catalyst in the development of the breed was market and consumerresistance to the carcass quality of traditional fat-tailed and fat-rumpedbreeds, such as the Afrikaner and the Persian, that made up most of thesheep farmed in the arid to semi-arid areas of the country during the1930s.An evaluation of the breedingstrategies used in the development ofthe Dorper sheep and the improvedBoer goat of South AfricaK. Ramsay, D. Swart, B. Olivier & G. HallowellRegistrar of Livestock Improvement and Identification,National Department of Agriculture, Private Bag X 138,Pretoria 0001, South AfricaIntroductionThe Dorpersheep340 Breeding Strategy WorkshopCase study: sheep in South AfricaThe Department of Agriculture initiated a series of trials from 1933 to1946 at research stations and participating farms in South Africa. Thiswas done in cooperation with farmers who had indigenous breeds todevelop a composite that could produce a quality carcass in harshconditions. This followed less controlled cross-breeding using rams fromexotic breeds such as the Suffolk, Border Leicester, South down, WelshMountain and the Dorset Horn. The largest disadvantage of the latterinitiative was the fact that, while breeding half crosses again to Britishmutton breeds improved carcass quality, adaptability decreased. The needto keep breeding flocks of less adapted pure British mutton breeds wasalso a problem.Trials to evaluate British mutton sire lines began in earnest at this stage.After analysing the results, it was decided in 1942 to develop a compositebreed using the half-cross Dorset Horn-Blackhead Persian as a basis. Ofparticular importance was the fact that this cross was less seasonal as faras breeding was concerned.The Grootfontein Research Institute of the Department of Agricultureplayed a major role in the further development of the breed. The overridingtrait in the breeding programme was adaptability. This can be describedas follows:• ability to survive unfavourable conditions;• ability to reproduce regularly in local conditions;• ability of lambs to grow rapidly to a marketable size.One of the major advantages of cooperative development is that it is easierto establish a half-cross composition this way. A sufficient number ofanimals exist to select and breed unrelated half-cross rams.Although numbers of the composite increased, progress was not asexpected until a breed society was formed in 1950. The name DORPERwas also established. The years that followed saw participation in thenational mutton performance testing scheme (introduced in 1964) and thedevelopment of the all white Dorper, a cross between the Dorset horn,Persian, Dorper and the Van Rooy sheep (an Afrikaner-Rambouilletcomposite).As the popularity of the Dorper increased, its distribution widened fromthe more traditional arid to semi-arid areas to include higher rainfall areasand semi-intensive production systems. Selection in these conditions aswell as buyer preferences had an influence on breeding objectives andbreed standards. Table 1 shows changes in 100 day masses of performancetestedIt can be seen that the Dorper has changed. It is shorter-legged and morecompact. Fat is more evenly distributed and the hair coat is short andsmooth. Performance data shows that growth has also improved.341Ramsay et al.ICAR Technical Series - No 3Can the breed still use the natural resources as effectively as it did in the1950s? Is the shorter sturdier modern Dorper still as adaptable?• Can it still move effectively in extensive conditions?• Does it still have the necessary adaptive traits?• Does it still graze effectively or has it become a destructive grazer?Lochner (1996) claimed that breeding objectives had moved from a hardyextensive type to a type more suited to temperate climates and Nel (1980)was of the opinion that selection for size and discrimination against certainfat deposits could possibly influence the breeds’ adaptive traits. VanNiekerk (1999) referred to changes as a result of breeding objectives thatcould influence sexual maturity and fertility and Campbell, (1998) advisedbreeders to pay attention to economically important traits of mutton sheepand to resist the temptation to intensively select for “fancy points”. Olivier(1999) advised that there should be a balance between marketability andthe genetic improvement of the breed.  Over emphasis in either directioncould do long-term damage to the whole breed.The Breed Society is located in Middelburg in the Cape Province, aboutten kilometres from Grootfontein Agricultural Development Institute.Close ties are maintained with key researchers and the Government stillcontributes a third to the running costs of the National performance-testingscheme that includes the small stock testing schemes.  Grootfontein hasalso recently developed a new recording and evaluation system underthe guidance of Dr Buks Olivier. The updated goal of the breed reflectsthese links.It is, however, important to constantly monitor breed progress with themost suitable aids available.Table 1. Changes in the 100 day masses of performancetested Dorper lambs (Data from the National Sheepperformance-testing scheme).Year 100 day weight (kg)Ram Lambs100 day weightEwe Lambs1964 25.40 24.201970 30.60 28.221978 30.96 28.031982 34.83 32.401989 34.80 31.50Is the modernDorper still asadaptable as itwas 50 yearsago?342 Breeding Strategy WorkshopCase study: sheep in South AfricaPerformance testing should be used sensibly to facilitate a balance betweenreproduction and growth.  The new small-stock recording andimprovement scheme that has been developed at Grootfontein is capableof meeting all these needs.It is encouraging to note that Grootfontein, the Institute that has contributedthe most to the development of the breed, continues to do so, using ahealthy balance between modern technology and phenotypic observation.This Institute would make an ideal small stock centre for Africa and hasall the necessary facilities to render advisory and support services to allfarmers and farm systems.Participation in the new scheme has increased rapidly over the last fewmonths owing to breeders and breed societies that had becomedisillusioned with performance testing. This is most encouraging andshows the Society’s commitment towards on-going evaluation andimprovement.Modern breed evaluation techniques will now enable those involved topredict trends as far as the major traits were concerned. With thisinformation, it will be possible to avoid a skewed approach to productiontraits where adaptability might be compromised by such directionsThe improved Boer Goat had its origins in the Eastern Cape Provincewhere farmers began keeping lop-eared goats obtained from Hottentotand Bantu owners. During the early stages, the goats were multi- colouredand were used in the thornveld areas to utilise and control bush.Although unsubstantiated, there are indications of early Eastern/Indianand European introductions. While these may have had an influence onsome animals, the overall breeding objectives did not take these intoconsideration.In the late 1920s and early 1930s a few breeders focussed breeding objectiveson improved conformation for meat production, quality meat and theability to browse. Colour selection followed and the typical white goatwith a red head began to establish itself as the only meat goat in Africa.The late Theunis Jordaan, a farmer from near Somerset West in the EasternCape Province, played a major role in this selection and developmentprogramme by concentrating on heavier short-haired goats with light redheads.A Boer Goat Breeders’ Association was formed on 4 July 1959. The aims ofthis society were to:• further improve the Boer Goat as a Breed in South Africa;• appoint an administrative staff;Improve theefficiency ofproduction ofa marketableproduct. Meatand SkinThe improvedBoer goat343Ramsay et al.ICAR Technical Series - No 3• implement an annual short course on Boer Goats and to train judgesand inspectors;• compile and distribute an information brochure and to organizedemonstrations to disseminate information regarding the breed;• establish an inspection service to class and inspect flocks;• introduce a more efficient grading system for Boer Goat meat;• stage sales and inspect all animals offered at sales under the auspicesof the association.Government support included trials in the late 1960s on grazing andbrowsing patterns and its impact on the improvement of grass coverage.This was followed by research into the productivity of the breed. Thisinformation was made available in the form of departmental publicationsand through the popular agriculture media. Other Government assistanceincluded technical advice and the establishment of herds at Dohne ResearchStation in the Eastern Cape and at Grootfontein in the Northern Cape.Additional institutional support came from the South African StudBookwho provided certification services as the only registering authority inthe country. Active membership of the South African Stud Book has,however, fluctuated over the years, particularly amongst breeders whosaw no need for recording and identification. Currently, there are12 breeders with a total of 3 866 animals registered with the South AfricanStud Book. Another eight breeders are currently being registered.The lack of recording in some herds recently led to problems whereembryos with no pedigree or performance information were exported toCanada. Prospective importers have been advised that only breed societyendorsed genetic material can be guaranteed.In 1964 when the mutton sheep performance testing scheme started Boergoat breeders joined the scheme. In 1970 a National Goat Performancetesting scheme was started under the mutton scheme. This schemeprovided a framework to record and evaluate the performance of goatsthrough the following phases:• Phase A: Records details of the dam, fertility, milk production and thegrowth rate of the kid/kids from birth to weaning;• Phase B: Records the post weaning growth rate of the kid;• Phase C: Records and determines the efficiency of feed conversionand the growth rate of male kids;• Phase D: Measures the post weaning growth rate of male kids instandard conditions at a central ram-testing centre;• Phase E : Determines the qualitative and quantitative carcasscomponents of the progeny of a specific sire.First phase ofthedevelopmentof the breed344 Breeding Strategy WorkshopCase study: sheep in South AfricaThe number of participants has fluctuated over the years. In 1975 therewere eight breeders with 500 ewes in the scheme and at present, there are12 breeders.Table 2 gives details of the mean adjusted 100 day mass (kg) of performancetested Boer Goat kids from 1970 to 1998.Second phaseof thedevelopmentof the breedTable 2. Mean adjusted 100 day mass(kg) of performance tested boer goatsfrom 1970 to 1998 (Data from theNational performance testing scheme).Year Ram(kg)Ewes(kg)1970 24.0 21.91975 23.6 21.71979 36.5 29.21982 32.3 27.81986 26.9 23.41988 25.3 22.3Although selection has been largely concentrated on the ability to producea saleable carcass off the savanna bushveld, there has been a tendencyamongst some breeders to select for ‘fancy points’, some of which may benegatively correlated with more important adaptive traits. Campbell (1990)who has played a key advisory role in the development of the breed formany years warned breeders not to pay too much attention to traits oflittle to no economic importance when selecting breeding stock.The breed was developed in the Eastern Cape where tick borne diseaseswere not a problem. Consequently, the Improved Boer goat has a lowlevel of resistance to heartwater (Cowdria) compared to unimproved goatsin areas where heartwater is endemic.Management practices and selection policies in some herds have also seena loss of maternal behaviour where ewes do not bond effectively withtheir kids.These issues show that there is no universal breed. The Improved Boergoat was developed with focussed breeding objectives to fit into a specificenvironment. The development was very successful and the animalsproduce more meat per unit area than any other goat breed in a similarenvironment. The breed is also being used very successfully in semi-intensive smallholder systems in many countries. Environmental factorsare of less importance where farmers can afford to make the necessarymanagement adjustments. It should, however, always be remembered345Ramsay et al.ICAR Technical Series - No 3that small stock are often of critical importance as the only sustainableform of animal production in arid to semi-arid areas. As such, adaptabilityand the ability to produce a useable/saleable product are the key overridingconsiderations.Future breeding plans must therefore always take aspects such asadaptability and production environment factors into consideration. Breedinformation should include production environment information to enableprospective breeders to make an informed choice.The strategies followed and experience gained during the developmentof the Dorper and the Improved Boer goat will be useful when formulatingguidelines for livestock breeding strategies for low input environments.In addition, modern animal recording and evaluation technology shouldbe adapted for use with specific programmes. This will enable plannersand farmers to ensure that objectives remain focussed.The role of the Government and supportive institutions should also betaken into consideration, particularly when it comes to identification,recording, evaluation of production traits and processing of performancedataIn developing guidelines, the following should be taken into consideration:• What are the objectives of the programme? Meat, milk, fibre, acombination?• What can the production environment support?• What genetic material is available and what is the potential of thismaterial?• What shortcomings are there in the general phenotype and genotype?• Can the available resource be used to produce?• What breeds can be used to develop a composite that will meet theneeds of the basic objective?• Will the development require institutional support? If so, in what form?and what is available?• What identification, recording and evaluation system will ensure thatthe primary objective remains focussed?Taking the Dorper as an example, modern breeding, recording andevaluation technology can assist in ensuring that the initial objective, thedevelopment of an adapted meat-producing sheep will remain focussed.Evaluations would be able to predict trends that could be rectified earlierthan present. Throughout this process, the following should always bekept in mind:Discussion.Using theexperience todevelopguidelines346 Breeding Strategy WorkshopCase study: sheep in South AfricaBreeding goals should always be defined in simple but explicit economicand biological terms. These include: more emphasis on reproduction rates,reducing the number of traits selected for by excluding those of doubtfuleconomic importance and maintaining effective herd/flock sizes andcomposition (Hofmeyr, 1978).Campbell, Q.P. 1984. The development of a meat producing goat inSouth Africa. Proc. 2nd World Congress on Sheep and Beef Cattle Breeding(1984).Campbell, Q.P. 1999. Personal communication.Casey, N. H. 1990. Meat, Dairy and Dual Purpose Goats: Meat as aPrimary and Secondary product with special reference to the Boer Goat.University of Pretoria – internal publication.Hofmeyr, J.H. 1978. The application of genetic resources for animalproduction in Southern Africa. S. Afr. J. Anim Prod. 8:(1) 69-78.Lochner, H. 1996. Stoetboere uit pas met kuddebehoeftes.Landbouweekblad 951: 10-13.Nel, J.A. 1993. Geskiedenis van die Dorper. DieDorperskaaptelersgenootskap van Suid Afrika. Middelburg, Cape.Olivier, J.J. 1999. Doeltreffende produksie per dier- sleutel virrasverbetering. Dorper News No. 58, 8-9.Olivier, J.J. 1999. Die Nasionale kleinveeverbeteringsskema.Presentation at a Dorper farmers day, June 1999.Olivier, J.J. 1999. Personal communication.van Niekerk, W. 1999. Dorperekologie. Dorper News No. 58, 44-45.References

An evaluation of the breeding strategies used in the development of the Dorper sheep and the improved Boer goat of South Africa

https://cgspace.cgiar.org/bitstream/10568/3931/1/CS1_26.pdf

An evaluation of the breeding strategies used in the development of the Dorper sheep and the improved Boer goat of South Africa

Abstract

Similar works

Full text

Available Versions

CGSpace