SECTION A
PRINCIPLES FOR GENETIC IMPROVEMENT OF INDIGENOUS ANIMALS IN THE TROPICS
To FAO/UNEP
1. The Panel recommends that:
2. The Panel recommends that FAO/UNEP should actively participate in the preparation of four publications:
The manual should include discussion of:
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monitoring animal performances;
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selection of outstanding individuals by population screening;
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interactions between experiment station and farmer herds;
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use of nucleus herds;
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establishment of societies for recording pedigree and performance;
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assignment of valid genetic values to bulls and cows;
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use of artificial insemination and embryo transfer;
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avoidance of inbreeding.
The manual should be aimed at administrators, extension officers and researchers and be in appropriate local languages.
3. The Panel recommends that FAO/UNEP should develop guidelines for national governments to use when deciding priorities to derive maximum benefits from the application of new technologies such as embryo transfer, artificial insemination, etc. to the improvement of a livestock species.
4. The Panel recommends that FAO/UNEP encourage the application of biotechnology to animal production and health. Priorities for the rapid application of biotechnology to livestock in developing countries should be drawn up.
To FAO/UNEP and National Governments
5. The Panel recommends that, in consultation with national governments in Latin America, FAO/UNEP should establish a permanent consultative committee on experimental designs for crossbreeding programmes in Latin Amercia involving Criollo and Zebu with European breeds. F1 hybrids have proved successful, but data are still scanty on the effect of continued crossing. The permanent committee should give priority to schemes which would add to knowledge, and should help design and implement an experiment or series of experiments to answer questions on unresolved areas of concern, such as:
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the extent of F1 heterosis (or recombination) at different levels of stress, and Its loss in subsequent generations;
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the efficiency of milk, meat and draught production, based on total lifetime merit.
6. The Panel recommends that, together with national governments, FAO/UNEP should establish procedures periodically to identify superior Sahiwal bulls and cows in India, Kenya and Pakistan; their use should be directed towards the propagation of superior F1 offspring for farmer programmes in tropical areas. The international sale of F1 Sahiwal hybrids of unknown dairy merit should be discouraged.
7. Where cattle breeds are spread over many countries, (e.g., the Sahiwal in Pakistan, India, Kenya, Malaysia, Australia, and so on), the Panel recommends that FAO/UNEP working with national governments should develop programmes of inter-country linkages so that data, semen, and embryos can be exchanged, with the aim of maximizing production and with due regard to animal health requirements. Such programmes could be developed between India and Latin American countries for the Ongole, GIR and Haryana breeds, and for the Criollo breeds.
To FAO/UNEP and National Governments
8. The Panel recommends that FAO/UNEP together with national governments:
9. Since most sheep breeds in the tropics have long breeding seasons and since in some breeds ewes cycle throughout the year, and in some sheep breeds' two peaks of breeding activity have been reported, the Panel recommends that more use should be made of this sheep trait. There is sufficient evidence under experiment station conditions to show that it is technically feasible to breed every eight months, but field tests should be made to identify practical problems under nomadic and transhumant conditions.
10. The Panel recommends that studies on the reproductive behaviour of indigenous sheep breeds in the tropical environment are needed, as there is growing interest in the use of hormones for synchronization of oestrus, superovulation and induction of early sexual maturity. However, the physiology of reproduction in the local environment should always be thoroughly investigated first.
11. The Panel recommends that research be encouraged to develop two strains of Java Thin-Tailed (JTT) sheep, one homozygous for the "prolificacy" gene and the other without it. Ewes of this breed show considerable variation in litter size. A homozygous strain should be uniformly high, while a strain without the gene would have singles or twins - an adequate level of prolificacy for most current practical management conditions.
12. The Panel recommends that for sheep meat production:
13. The Panel recommends that for wool production:
14. Since some Indian goat breeds with valuable genetic traits are declining numerically {for example the Barbari, present population 30 000, and Jamunapari 5000), the Panel recommends that conservation is needed.
15. Since selection within breeds of sheep and goats seems the most favourable method at present for genetic improvement of small ruminants, the Panel recommends that such schemes should take account of habitat and flock size. The practice of population screening for individuals of outstanding merit should be more widely used to supplement normal selection and breeding methods. It should be noted that crossbreeding and development of new breeds should also have a place under improved husbandry conditions and in the more developed countries; also that milk production in goats can be improved through selection for first lactation milk yield and age at first kidding.
The camel species is widely distributed among the Far Eastern (two-humped camel), Middle Eastern, North African and Sahelian (one humped) countries. The species is well adapted to desert climates and is used for milk, meat, draught, transport and racing. Camelidae exist in the Andean high altitude areas, where pastoralism is the main activity.
The Panel took note of the extreme importance of camels in providing milk, meat and transport for populations living in sub-desert and desert areas, and of the camelidae in producing meat, fibre and transport for people in the Andean regions. It recognized there are still wide gaps in knowledge about both camels and camelidae.
To FAO/UNEP and National Governments
16. The Panel recommends that FAO/UNEP:
17. The Panel recommends that:
The Panel noted that in most developing countries, two kinds of pig production have developed over the last three decades:
18. The Panel recommends that FAO/UNEP:
19. The Panel recommends:
20. The Panel recommends that FAO/UNEP:
There was general agreement on the high priority to be attached to education and training in the tropics. Courses of various kinds should be set up with defined objectives using methods and languages appropriate to the participants. While courses should be set at suitable technical levels it was emphasized that screening of applicants is essential. The proper sharing of experiences will only be achieved by bringing in some experts from outside the Region and at the same time balancing this with local personnel with a good knowledge of local production requirements. In this latter respect it is very important to appreciate socio-economic aspects of current animal production and their interaction with the intended changes.
21. To FAO/UNEP the Panel recommends that FAO/UNEP, in association with national governments, should organize training courses at three levels:
22. Training manuals should be compiled in association with the planning of the relevant courses above.
23. The Panel recommends that FAO/UNEP should make special merit awards to recognize outstanding performance by individual technicians. This is suggested to encourage pride in achievement; strong motivation is required to create close involvement and commitment from the farming community.
24. On the subject matter of courses, the Panel recognizes that various types of courses will be required varying in length and technical content according to particular requirements. It recommends the following subjects to be considered:
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animal breeding and genetics (including organizational aspects);
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conservation and management of animal genetic resources;
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design and analysis of genetic experiments;
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data acquisition; data banks and computing;
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cryopreservation and techniques for the manipulation of reproduction;
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extension methods and socio-economic factors.
25. The Panel recommends that:
Embryo transfer is a basic method in all aspects of applied and experimental embryology, and knowledge of embryo collection, evaluation and freezing is essential in relation to cryo-preservation of genetic material from endangered breeds and in the improved utilization of germ plasm in certain situations.
26. To FAO/UNEP the Panel recommends that:
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embryo manipulation
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fertilization in vitro
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production of transgenic animals.
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electro-ejaculation, which, however, gives semen of lower quality;
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use of the imprinting effect, which involves artificial rearing of newborn males, but leads to easy handling of mature animals.
27. The Panel recognizes that although specific information is not available on decline in numbers in various tropical breed populations, indiscriminate crossing with temperate exotics is putting many of these populations in danger of extinction, e.g. Criollo breeds of Latin America, Sahiwals of India, Pakistan and Kenya, Jamnapari goats of India, Siri cattle of Bhutan and India. The need for preservation/conservation of breeds and local populations with specific adaptations, some of which are clearly endangered for various reasons, has now been clearly established.
A number of methods for preservation have been identified and costs worked out for each. There are two main categories:
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in situ preservation of live animals;
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ex situ preservation of parts in cryogenic storage.
Advantages of the in situ method are:
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the animals are visible, and so pleasing to the eye, and have some cultural value;
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they are a gene bank for future use;
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they are a constant reminder that the needs of posterity must be considered;
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the herd/flock may have some economic advantage (e.g. disease resistance in chickens) which can be exploited and so render the enterprise economically viable.
The costs of in situ preservation worked out so far for Europe are not applicable to many tropical countries; these could be much less and need to be estimated for each ecosystem.
Disadvantages of the in situ method are:
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small population size, leading to inbreeding and random drift. Many models are now available which reduce inbreeding to a minimum, but some scientists argue that random drift over long periods (say hundreds of years; may lead to a population very different in genetic composition from the initial one;
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gene x environment interactions.
Because of random drift and possible gene by environment inter actions, ex situ methods are generally preferred over in situ.
Ex situ storage can be of semen, ova or embryos. At present, embryos are preferred for obvious reasons, as the breed can be reconstructed at any time. There is agreement, however, that it is desirable to store semen as well as embryos.
The fast growing science of biotechnology may lead to newer techniques of gene preservation. DNA recombinant techniques, embryo manipulation, cloning of desirable genes from the same or other breed populations may one day become commonplace.
28. To FAO/UNEP the Panel therefore recommends that:
29. The Panel recommends that:
30. The Panel recommends that:
There is a substantial risk of transferring contaminating agents when cryo-preservation of genetic material is used for breeds not kept under strict hygienic control.
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semen may be contaminated;
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viruses may stick to the zona pellucida of the embryos;
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contaminating agents are effectively frozen with semen or embryos and may be preserved indefinitely;
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contaminating agents cannot be removed from semen;
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addition of antibiotics does not offer guarantee of neutralization of contaminating agents.
31. To FAO/UNEP the Panel recommends that: