Evaluation of chemical composition of duck's muscles from three conservative flocks Bestimmung der chemischen Zusammensetzung der Muskeln von Enten aus drei Erhal- tungszuchtherden

The conservation of domestic animal diversity (DAD), including poultry, is justified for biological, economic and even cultural or historic reasons (BAUMGARTNER et al., 1995; CRAWFORD, 1993). An inventory of the world’s poultry genetic resources was drawn up under the auspices of FAO to protect animals living in nature as well as breeds, lines and varieties developed by man and threatened with extinction. In Poland the idea of the conservation of genetic resources of ducks and their protection against extinction dates back to the early 1970 s (KSIAZKIEWICZ, 2002). The genetic diversity found among breeds is taken to account for one half of the genetic variability that occurs within species. From the breeding point of view, the maintenance of genetically diversified bird flocks is necessary to ensure genetic variability in the selected populations. In the case of ducks these flocks were used to develop new breeding and experimental strains and synthetic lines as well as to find heterosis effects in commercial sets (KSIAZKIEWICZ, 1995 and 1997a; KSIAZKIEWICZ and KIELCZEWSKI, 1999; PRUSZYNSKA et al., 2001). In Poland, more than ten conservative and genetic reserve flocks of ducks are now under the conservation programme, two conservative flocks of Polish-origin ducks, i.e. Pekin (P33) and Miniducks (K2) have been listed by FAO (WORLD WATCH LIST, 2000) and registered as the protected world genetic resources. The breeding programme for the preservation of duck genetic resources, which specifies, among others, the methods of management, evaluation and mating of parental stocks and size of the population, is carried out in Poland in the National Research Institute of Animal Production in Krakow. The populations of P33, K2 and A3 ducks have been tested for reproductive and meatiness traits so far (KSIAZKIEWICZ, 2002). The Polish Pekin (P33) is derived from an old indigenous breeding strain subjected to selection and taken from the farm at Borowy Mlyn. The Polish Pekin (P33) was developed in 1978 in the Poznan region. It has self-white plumage with no special pattern of feathers. It possesses