This study examined the relationships among physicochemical properties and ultrasonographic image attributes of pectoralis major muscles in broiler chickens. Forty male Ross 308 chicks were randomly assigned to four equinumerous fat-supplementation groups (Group SO: soybean oil; Group FO: flax oil; Group SO + FO: soybean oil + flax oil; and Group BF: beef fat). Ultrasonograms of birds’ pectoral muscles were obtained just before slaughter at 6 weeks of age and were subjected to digital image analyses to determine the mean pixel intensity (MPI) and pixel heterogeneity values (standard deviation of numerical pixel values; MPH). A total of 2, 4, 2, and 6 significant correlations were recorded in Groups SO, FO, SO + FO, and BF, respectively; there were no correlations with the chemical composition of the muscles in Groups SO and SO + FO. The strongest correlations were found between muscle lightness (L*) and MPH in Group BF (physical characteristic; r = −0.82, p = 0.003), and between crude fat/protein content and MPI/MPH of pectoral the major muscles in Groups FO/BF (chemical characteristics; r = 0.72, p = 0.02). There exists a potential application of ultrasonographic imaging and computerized image analysis for predicting certain physicochemical properties of pectoralis major muscles in broiler chickens.

BackgroundThe lack of a sufficient number of molecular markers seriously limits the cognition of genetic relationships within and between populations of many species. Likewise, the genetic diversity of domestic goose (Anser anser domesticus), with a great number of breeds throughout the world, remains poorly understood at the molecular level.FindingsThirty-five goose, seventeen duck and eight chicken microsatellite primer pairs were screened for their utility in the cross-species amplification on DNA from 96 individuals of Zatorska breed of domestic geese. Twenty-seven of 42 amplifying primer pairs revealed length-polymorphic products, but three of them were difficult to score. Fifteen primer pairs amplifying the same length product across all individuals. One polymorphic microsatellite locus was assigned by genotyping of known sex individuals to the Z-chromosome.ConclusionsWe present a set of 24 polymorphic microsatellite markers useful for population genetic studies of the domestic goose. Another 15 markers were classified as monomorphic, but they might also be suitable for the assessment of genetic diversity in geese.

ABSTRACT:The structure of the Zatorska breed was estimated in the context of the realized conservation program. The level of genetic diversity and effective population size were estimated as well. The following parameters were evaluated: pedigree completeness index, genetic diversity, inbreeding level, individual increase in inbreeding, generation interval, and parameters connected with general condition of the population. The whole population of the Zatorska breed was housed in an experimental farm of the University of Agriculture in Cracow (Poland). Records were extracted from the studbook. Totally 5514 individuals hatched between 1990-2013 (2835 males and 2679 females) were included in the analysis. The average number of discrete generation equivalents reached 3.76, whereas the maximum discrete generation equivalent was 9.98. The average inbreeding level was low amounting to 1.46% for the whole population and 3.02% for the inbred individuals. The average pedigree completeness index for five generations reached 59.12%, for 10 generations 37.39%, and for all 16 generations it was 23.53%. The average effective population size was estimated from the family size variance and amounted to 67.36 individuals. It can be concluded that the conservation breeding program in the Zatorska goose has been going on well. This is confirmed by the magnitude of obtained estimates of parameters such as a low inbreeding level across generations under satisfactory pedigree completeness. On the other hand, the structure of a small population may be liable to fluctuations. Hence, continuous monitoring of the endangered population (including molecular control) seems to be necessary.

Brooding behavior, a common characteristic of native breeds of the domestic chicken, is marked by elevated prolactin ( PRL ) levels, which is necessary for incubation and connected with changes in hypothalamic–pituitary–gonadal axis activity. Evidence indicates the serotoninergic system is a potent modulator of PRL secretion. The objective of this study is to investigate whether blocking serotonin synthesis with parachlorophenylalanine ( PCPA ) prevents incubation behavior in native Polish crested chickens. In addition, we examined the effect of PCPA on the gene expression of the gonadal and lactotrophic axes. Birds were stimulated to broodiness by artificial eggs in nests. At 34 wk of age (April: spring period), the hens were divided into 2 groups (14 hens in each group): control and PCPA-treated (50 mg/kg BW) group. After 5 wk of treatment, the artificial eggs were removed from the nests. Egg production, incubation activity, and levels of plasma ovarian steroids progesterone ( P4 ), testosterone ( T ), estradiol ( E2 ), and PRL were examined. At the end of the experiment (45 wk of age, June: summer period), ovarian characteristics and mRNA gene expression of gonadal (gonadotropin-releasing hormone [ GnRH ] I, luteinizing hormone [ LH ] ß, follicle-stimulating hormone [ FSH ] ß) and lactotrophic (vasoactive intestinal peptide [ VIP ], PRL) axes were measured by quantitative real-time PCR. Incubation activity was observed in the hens of both groups but with lower frequency in PCPA-treated birds. Moreover, the PCPA group had a higher cumulative egg production than the controls. During the first six and 8 wk of the experiment, levels of P4 and E2, respectively, were similar in both groups, but all concentrations increased in the PCPA-treated hens after this period. In addition, increased GnRH-I, LHß, and FSHß and decreased VIP mRNA expression was observed in the PCPA group compared with the controls. There were no differences in PRL mRNA expression, the PRL level, and ovarian morphometry between the 2 groups. These results indicate that blockage of serotonin synthesis by PCPA does not effectively prevent incubation in native Polish crested chickens. However, treatment with PCPA increased gonadal axis activity and improved reproductive performance.

The experiment was aimed at the evaluation of inheritance of goose egg measurements, egg shape indices and egg weight as well as the relationship between these traits. The research was carried out in the flock of the Zatorska geese, belonging to the FAO registered genetic resources of poultry. Seven hundred sixty-one eggs from pedigree bred geese in their first to fourth reproduction seasons were included in the analysis. Average egg shape index was 68.8%, average shell surface area was 140.6 cm 2. Egg weight of geese in different age was 165 g. Heritabilities and genetic and phenotypic correlations estimated between the analysed traits of goose egg are presented.