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Appendix 1

FAO Activities on Animal Resources
(taken from Hodges, 1990b)

A. Publications

1948Breeding livestock adapted to unfavourable environments
1950Improving livestock under tropical and sub-tropical conditions
1950Report of the inter-American Meeting on Livestock Production
1953Zebu cattle of India and Pakistan
1957Types and Breeds of African Cattle
1958Pig Breeding, Recording and Progeny Testing in European Countries
1966European Breeds of Cattle, Vols I and II
1967Sheep Breeds of the Mediterranean
1970Observations on the Goat
1970The Buffaloes of China
1974The Husbandry and Health of the Domestic Buffalo
1977Animal Breeding: Selected Articles from World Animal Review
1977Bibliography on the Criollo Cattle of the Americas
1977Mediterranean Cattle and Sheep in Crossbreeding
1978Declining Breeds of Mediterranean Sheep
1979The Sheep Breeds of Afghanistan, Iran and Turkey
1979Dairy Cattle Breeding in the Humid Tropics
1980Prolific Tropical Sheep
1980Trypanotolerant Livestock in West and Central Africa, Vols 1 and 2
1980Informe de la Consulta de Expertos FAO/PNUMA Sobre la Evaluacion y Conservacion de Recursos Geneticos Animales en America Latina
1981Animal Genetic Resources - Conservation and Management
1982Sheep and Goat Breeds in India
1982Breeding Plans for Ruminant Livestock in the Tropics
1984Animal Genetic Resources: Conservation by Management, Data Banks and Training
1984Animal Genetic Resources: Cryogenic Storage of Germplasm and Molecular Engineering
1985Livestock Breeds of China
1985Animal Genetic Resources in Africa: High potential and Endangered Livestock
1985Sheep and Goats in Pakistan
1985Awassi Sheep
1986Animal Genetic Resource Data Banks
1. Computer Systems Study for Regional Data Banks
2. Descriptor Lists for Cattle, Buffalo, Pigs, Sheep and Goats
3. Descriptor Lists for Poultry
1986Sheep and Goats in Turkey
1986The Przewalski Horse and Restoration to its Natural Habitat in Mongolia
1987Animal Genetic Resources - Strategies for Improved Use and Conservation
1987Trypanotolerant Cattle and Livestock Development in West and Central Africa, Vols 1 and 2
1987Crossbreeding Bos Indicus and Bos Taurus for Milk Production in the Tropics
1988Biotechnology applicable to Animal Production and Health in Asia
1989Animal Genetic Resources of the USSR
1989Biotechnology for Livestock Production
1989Ex situ Cryoconservation of Genomes and Genes of Endangered Breeds by means of Modern Biotechnological Methods
1990Animal Genetic Resources: A Global Programme for Sustainable Development
1990Reproduction in Camels
1990Open Nucleus Breeding Schemes for Cattle and Buffalo

Animal Genetic Resources Information (AGRI)
This newsletter has been published during the period 1983–90 and contains update information on activities on a world scale, articles of particular relevance on endangered or highly used breeds, methodologies, book reviews and reports of meetings. It is designed to reach all who are interested and concerned with Animal Genetic Resources and is distributed free to a mailing list of 1,500 people and institutions throughout the world. Funding has been provided by UNEP.

B. Conservation Activities

1983–1986A large scale pilot project to develop a new system of Animal Descriptors was carried out and resulted in the development of a system for the orderly genetic characterization of the breeds and of the environments to which they are adapted.
1983–1985Pilot studies of alternative options for ex situ and in situ preservation of endangered breeds.
1986-An international research project to investigate the genetic structure of Sahiwal cattle is being undertaken jointly with India, Kenya and Pakistan supported by trust funds and technical input from Sweden. The expected output is a programme for increased use of the breed in dairy programmes of developed countries, thus preserving its value germplasm.
1988-Regional Animal Gene Banks in Latin America, Africa and Asia for the cryogenic storage of semen and embryos have been established. The banks will become operational in 1990 after training of nationals of participating countries is undertaken. An Operating Manual for Gene Banks has been prepared.
1988-The EAAP/FAO Global Animal Genetic Data Bank was established in Hanover, FRG to hold genetic characterizations and population census data. These are stored, analyzed and available for access.

C. Meetings

1967FAO study on the Evaluation, Utilization and Conservation of Animal Genetic Resources.
1969FAO Second ad hoc Study group on Animal Genetic Resources.
1971FAO Third ad hoc Study Group on Animal Genetic Resources (Pig Breeding).
1973FAO Fourth ad hoc Study Group on Animal Genetic Resources (poultry breeding)
1980FAO/UNEP Technical Consultation on Animal Genetic Resources Conservation and Management
1983OAU/FAO/UNEP Animal Genetic Resources in Africa
1983First FAO/UNEP Expert Panel Meeting on Animal Genetic Resources Conservation and Management
1985FAO/UNEP Expert Consultation on Animal Genetic Resources Conservation and Management - Methodology for Data Banks
1986Expert Consultation on Biotechnology applications
1985FAO/UNEP Expert Consultation on the Przewalski Horse
1986Second FAO/UNEP Expert Consultation on Animal Genetic Resources Conservation and Management
1989Consultative Workshop for co-ordinators of Regional Animal Gene Bank Centres
1989Workshop on Open Nucleus Breeding Systems
1989Expert Consultation on FAO Programme for Animal Genetic Resources

D. Training Courses

1983FAO/UNEP Training Course on Animal Genetic Resources - Conservation and Management
1988Embryo Transfer Training Course in Czechoslovakia
1989Embryo Transfer Training Course in Cuba
1989Embryo Transfer Training Course in China
1989Staff from national Bureaux or animal genetic resources in China and India trained at Global Animal Genetic Data Bank, Hanover, FRG
1990Open Nucleus Breeding Schemes for Buffalo in Bulgaria
1990In vitro fertilization (IVF) for cattle in Brazil
1991Training Course for 2 participants from each of 12 Latin American countries on operation of Regional Animal Gene Bank in Brazil
1992Training Course for 2 participants from each of 15 Asian countries on operation of Regional Animal Gene Bank in China

Appendix 3.1

General guidelines to decide when to intervene for conservation of natural populations

Priority Population
possiblyN < 100,000At least serious surveillance of status and trends should be initiated
probablyN < 10,000Well managed captive propagation programmes should be established, reproductive technology research should be vigorously conducted, and germinal tissues collected for storage, while there are an adequate number of animals to use as founders, subjects and donors.
certainlyN < 1,000Ex situ programmes should be intensified while field (in situ) efforts are fortified for a 'last stand'; ex situ programmes are imperative.
urgentlyN < 500Ex situ programmes assume at least as much importance as field (in situ) efforts.

It would be better to predicate these guidelines on actual Ne's rather than N's. However, effective population sizes have been and will be difficult to measure for wild populations. Not only is information on sex ratios and family sizes often insufficient, but subdivision of the population and lack of data on rates of gene flow among subpopulations will complicate estimates. Nevertheless in these cases, a quick approximation may be:

Ne = 4 Nm Nf/Nm + Nf

where Nm = the estimated number of adult males
Nf = the estimated number of adult females

(after Notter and Foose, 1987)

Appendix 3.2

Calculation of the Effective Population Size

Mathematical expressions of the effective population number (Ne) have been derived for a variety of special population structures and will be reviewed in this appendix

A. Unequal Number of Breeding Males and Females

Ne = (4MF)/(M + F)(1)

where M is the number of males and F is the number of females (eg, Crow and Kimura, 1970). Ne is primarily controlled by the sex (usually male) present in smallest numbers. For example, M = 10 and F = 100, the total census number is 110 but Ne = 36.

B. Fluctuation in Population Numbers Across Generations

Ne is given by the harmonic mean population number (eg, Crow and Kimura, 1970):


Where Ni is the population number in each of t generations. Ne is seriously reduced by periods of small N. If Ni = 100 in nine of 10 generations but is reduced to Ni = 10 in one generation, Ne = 53.

C. Non random Distribution of Progeny Numbers

In an ideal population, each parent is assumed to be equally likely to contribute progeny to the next generation. This implies a Poisson distribution of family sizes with the variance in family size (σ2k) equal to the mean family size, k (which is equal to two in a population of constant size). However, in many populations σ2k exceeds k. Mathematically:


where N is the actual population number (Crow and Morton, 1955). Note also that in managed populations, if each mated pair contributes exactly two offspring to the next generation, σ2k = 0 and Ne = 2N.

D. Joint Effects of Sex Ratio and Distribution of Family Size

Hill (1972) demonstrated that in this situation:


where M and F are the numbers of males and females, respectively, σ2m is the variance among sires in number of male progeny, σ2mf is the variance among sires in the number of female progeny and σmm,mf is the covariance among sires in numbers of male and female progeny. The quantities σ2fm, σ2ff and σfm,ff are comparable values for dam progeny numbers.

In a simplified derivation, Gowe at al, (1959) demonstrated that if each sire produces exactly one male and F/M daughters and each dam produces exactly one daughter and a son with probability M/F, equation (4) becomes:

(1/Ne) = (3/16M) + (1/16F)(5)

Smith (1976) also modified equation (4) to estimate the effect of failure of sires and dams to produce appropriate replacements such that:

(1/Ne) = (1/16M) (4.17 - 2pm) + (1/16F) (4.17 - 2pf)(6)

where p is the probability that a male or female will survive and produce the required number of progeny.

(after Notter and Foose, 1987)

Appendix 5.4

A Procedure for Developing an Optimal Level of Subdivision within a Captive Population

A decision regarding the extent to which population subdivision is indicated can be based on the following logic:

  1. Develop a goal for the amount of genetic diversity that is to be conserved. This can be expressed in a variety of ways, but for purposes of example, let it be described in terms of the percentage of the initial heterozygosity that is to be maintained for a given number of generations. Let us assume an arbitrary goal of maintenance of 90% of the initial heterozygosity for 100 generations. From equation (1) of the text, this would require a panmictic (non-subdivided) population of effective size Ne = 356.

  2. Let the maximum rate of inbreeding that is consistent with the continued fitness of the species (Δ F MAX) be arbitrarily set at 1.5% generation. In reality, this value would have to be determined separately for each species. If ΔF MAX = .015/generation, then the minimum effective size of a subline (Ns) is given as

    Δ F MAX = 1/2 Ns = .015

    such that Ns = 33.3. After 100 generations of random mating, only 22% of the initial heterozygosity is expected to be retained for any single line with Ns = 33.3.

  3. For a population composed of k sublines the heterozygosity expressed in a composite population derived by crossing the sublines with subsequent random mating is directly proportional to the number of sublines. Such a population would be a reasonable one for reintroduction of a species into the wild and would have

    1 -H't/Ho = (1/k) (1 - Ht/Ho) = (1/k) [1 - (1 - 1/2NS)t]

    where Ho is the original heterozygosity, Ht is the remaining heterozygosity within a subline at generation t and Ht is the heterozygosity within the composite population derived by crossing the lines. For Ns = 33.3 and t = 100,

    1 - H't/Ho = (1/K) [1 - (1/66.6)100]

    If we let (1 - Ht/Ho) equal to .10 (the goal of the conservation programme), k = 7.80. Thus for 8 lines of size Ns = 33.3, the loss in heterozygosity would be restricted to 9.7%. A total effective population size of 266.4 would be required for the subdivided population and would compare to a value of Ne = 356 which would abe required to achieve the same result in a totally panmictic population.

(after Notter and Foose, 1987)

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