Contrary to chicken and livestock mammals, duck genome has not been explored much. Nowadays a relatively small number of reports on molecular variability and mapping of loci in Peking ducks has been published. Therefore, the objective of this study was to detect single loci affecting body weight, carcass and meat traits in Peking ducks (Anas platyrhynchos). The study was based on an F2 cross between two parental lines A-55 and GL-30. Phenotypes of 387 birds from generation F2 including carcass and meat quality traits were collected. Linkage map, of the linkage group CAU1, consisting of 29 microsatellite markers was constructed. One highly significant (p < 0.01) QTL for skin weight was identified at the beginning (0 cM) of the linkage group CAU1. Two significant QTL (p < 0.05) were found for fatness of leg muscle and leg muscle electrical conductivity - 24 hours post slaughtering (EC24h) at 178 and 100 cM, respectively. Additionally one suggestive QTL for odour of leg muscle was identified at 265 cM.

Blastoderm cells from chicken embryos of a donor breed (Green-legged Partridgelike; GP) were transferred to embryos of a recipient breed (White Leghorn; WL) to form chimeric progeny that, after inter se mating, permitted successful reconstitution of the donor breed. Among 23 chimeric chicks hatched from WL embryos injected with GP cells, 20 (87%) were raised until maturity, and progeny were tested by mating with GP birds to determine the ability of blastodermal cells to form germline chimeras. Six of the tested birds (30%) produced recipient-derived and donor-derived offspring, indicating that they were germline chimeras. The mean percentages of donor-derived germ cells in these birds were 21.1 (17.6 to 50.0%) and 16.9 (5.3 to 23.1%) in males and females, respectively. Among 477 chicks, resulting from mating the germline chimeric male with four germline chimeric females, 10 chicks (2.1%) exhibited a GP phenotype, indicating that the original donor stock had been reconstituted. Only one germline chimeric hen produced GP offspring, but the expected and calculated percentages of GP offspring were similar (2.99 and 2.08, respectively). Two methods of DNA analyses (RFLP and PCR amplification of polymorphic microsatellite loci) of chimeras and their offspring indicated that through mating of a relatively small number of chimeras it is possible to reconstitute a highly diverse population.

The aim of this study was to genetically analyse by the RAPD-PCR method four indigenous Polish goose breeds, Kartuska (Ka), Lubelska (Lu), Kielecka (Ki) and Podkarpacka (Pd), in order to determine the band-sharing frequency as well as bands characteristic of the evaluated breeds. The birds were maintained as conservative flocks, accounting for a reserve of genetic resources. A total of 102 scorable bands were obtained, their number ranging from 0 to 8, depending on one of seven primers used and the group of birds analyzed, within a mean of 3.64. For each genetic group specific bands with given primers were obtained, suggesting their potential for use as population-specific markers, especially in ex-situ conservation methods. The results also suggest that keeping endangered geese as separate flocks is relevant for their preservation.

The aim of this study was to estimate coefficients of heritability as well as genetic and phenotypic correlations among body weight and carcass traits. The dataset contained records of 387 birds from the second crossbred generation. The following traits were recorded: body weight (BW) at 11 weeks, carcass weight (CW), breast muscle weight including superficial and deep muscle (BMW), leg muscle weight including thigh and shank (LMW), wings weight (WW), skin with subcutaneous fat weight (SW), abdominal fat weight (AFW), skeleton with the back muscle and inedible elements (SBM), and liver weight (LW). Estimates of variance components were obtained by the average information -REML algorithm in the ASReml package. Very high slaughter yield (74.90%) was obtained. Generally, the coefficients of heritability were high. The highest one of 0.75 was estimated for body weight at 11 weeks. High coefficients of h 2 were estimated for breast muscle weight (0.69), wings weight (0.70), carcass weight (0.65), skin with subcutaneous fat weight (0.57) and skeleton with the back muscle (0.58), whereas h 2 of liver weight was 0.29. Both phenotypic and genetic relationships between the recorded traits were usually positive. Generally, it seems that the crossbreeding scheme can be perceived as a suitable proposal for the breeding practice.

Simple Summary: Identification of mutations in the myostatin gene, affecting the occurrence of the double muscling phenotype in some breeds of beef cattle, was an impetus for further analysis and identification of mutations within this gene in other animal breeds, characterized by increased meat performance parameters. The number of geese in poultry livestock production in Poland is small. The native geese breeds can be successfully used to produce high-quality poultry meat and can be a very good source of goose meat production for regional and organic products. The aim of the study was to identify a mutation in the MSTN (Myostatin) gene and investigate whether this polymorphism can affect body weight in different periods of life in Landes and Kielecka breeds. Measurements of the examined trait were taken with time intervals to demonstrate the putative effect of the identified SNP (Single Nucleotide Polymorphism) on body weight over the course of bird growth. In conclusion, the identified c.1231C>T polymorphism suggests a possible link between the polymorphism and the BW (body weight) of Kielecka geese in the 12th week of life. The most significant factors affecting the BW values in geese are breed and sex.Abstract: Myostatin, also known as growth differentiation factor 8 (GDF8), belongs to the TGF-β superfamily of proteins. MSTN is a highly conserved protein that acts as a negative regulator of skeletal muscle growth. Loss of myostatin functionality causes the phenotype to appear in the form of 'double musculature', among others in cattle, sheep, and house mice. The presented results of the research were carried out on two geese breeds-Landes and Kielecka. The aim of the study was to identify mutations in the MSTN gene and study their impact on body weight in both geese breeds in different periods of life. Analysis of the obtained results showed the existence of polymorphism in exon 3 (c.1231C>T) and suggested a possible association (p < 0.05) between BW and genotype in 12 weeks of life in male Kielecka geese breed. The identified polymorphism may be one of the factors important for improving body weight in the studied Kielecka breed, therefore, it is necessary to conduct further research on a larger population of geese breeds in order to more accurately estimate the effect of the identified SNP c.1231C>T on BW in geese.