Safeguarding the Genetic Legacy:
Aims, Objectives & Methods

Until some decades ago, Italy was endowed with a vast diversity in its population of domestic breeds. This diversity had come to exist through the centuries, thanks to the environmental diversification which presents itself in the Italian peninsula from the Alps to the Apennines, from the fertile soil of its lowlands to the Mediterranean bush and further to the arid areas of the South and the Islands. Furthermore, to such diversification contributed also a history of uninterrupted migrations of human and animal populations. Due to the progressive reduction of agricultural areas and the decrease of husbandry-employed human resources on the one hand, and to the industrialization with the consequent uniformity in production processes on the other, the peninsula's original biodiversity has been sensibly reduced. Suffice to say that a substantial part of the breeds which until the 1950s were bred in large numbers can be found represented at present by no more than a few hundreds or even a few dozens specimens, which classifies them as in danger of extinction.
The objectives of safeguarding endangered breeds can be summarized as follows:
· Promoting extensive animal husbandry in peripheral or marginal areas; In this respect it must be remembered that certain breeds are part of ecosystems that need to be safeguarded; preserving such breeds, therefore, is one of the means to achieve environmental management.
· Preserving the cultural inheritance which indigenous breeds in themselves represent.
· Preventing the loss of genetic material, not only as genes by themselves but also as their combination, before such material has been exhaustingly evaluated.
· Preventing the loss of genetic material which can be employed for future production needs, in case for instance of changing consumption habits in humans, altered environmental situations, or diversified breeding conditions and goals.
· Maintaining genetic material which is potentially resistant to unexpected epidemics.
There are generally speaking two safeguarding strategies being applied:
· Ex-situ or external; this implies preserving genetic material in both aploid (sperm, egg cells) and diploid (embryos), as well as DNA chains. However, these techniques are not applicable in the poultry keeping industry. To this strategy belongs also keeping live stock in zoos, natural reservations and parks, experimental farms or other institutes.
In-situ or internal; this implies keeping the breed's specimens within its production system, that is to say in its environment, on the ground of and focusing on its productive characteristics.
The in-situ strategy presents the following advantages: It allows to improve the often insufficient knowledge about the role and importance of a specific genetic resource in its practical and continuous utilisation; it also stimulates investments aimed at the social and financial development of disadvantaged areas, where the breeds' diversification is generally the highest. This translates directly into the breeding of local breeds, and indirectly allows to preserve diversity in vegetation, animal population, territorial management and cultural heritage. In its broadest sense, the in-situ or internal method is one that safeguards diversity while respecting its evolutionary dynamics.
The first problem one is confronted with when working with a small population is doubtlessly the in-breeding degree within the population itself. In-breeding reduces genetic diversity and consequently the breed's ability to adapt to its environment and respond to selection, thus causing a depression of certain productive characteristics. To the afore mentioned factors one needs to add the inevitable genetic drift that, by fixing the one allele, consequently causes the loss of the other one. In order to limit the negative consequences of close relationship, as far as possible, the so-called Genetic Management Models are being used. Such a model is based on three strategies, which find successful application in the poultry keeping industry too:
· Maximise the actual amount of specimens within a population;.
· Minimize the degree of consanguinity between the breeding specimens;
· Devise a mating plan.
Increasing the number of specimens actually involved in breeding implies keeping a number of male breeders as high as possible, ideally as high as the female's. Besides, the offspring should ideally be the same in number for every single breeder.
Reducing to the minimum the degree of consanguinity between the breeders, as recently shown by computer-aided simulation, results in the possibility to select new breeding specimens for every generation based on their relationship degree. These two criteria find practical application in the planning of the mating, a short-term policy that delays close relationship rather than reducing its rate of increase, as proven by means of computer simulated planning in which the relationship between the breeders was minimised at every mating.

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