Genetic evaluation of reproductive potential in the Zatorska goose under a conservation program.

The aim of this study was to estimate the genetic parameters and inbreeding effect on the fertility, embryo mortality and hatchability traits in the Zatorska goose covered by the animal genetic resources conservation program. The material for this study contains information about results of hatching of 18 863 eggs from 721 dams and 168 sires, laid between 1998-2015. Genetic parameters were estimated based on the threshold animal model by the use of Restricted Maximum Likelihood and Gibbs sampling. The percentage of fertilized eggs ranged yearly between 37-80%. The percentage of embryo mortality was very low, ranging between 4.63-23.73%. The percentage of the hatched goslings from the total number of analyzed eggs was on average 33.18%, and 53.72% from fertilized eggs. On average based on both methods, the heritability estimates of the fertility, embryo mortality and hatchability reached 0.36, 0.07, 0.24 for males and 0.44, 0.11, 0.32 for females. The genetic trend had increasing tendency for fertility and hatchability and was stable for embryo mortality for both sexes. The obtained result shows that the Zatorska goose can be still maintained in the reserves of the local gene pool according to current rules and use in the local market as a breed with good reproductive potential.

Zatorska goose - a subject of parasitological research.

The aim of the study was to determine the level of gastrointestinal parasites in a native breed of geese - Zatorska goose - based on coproscopic testing. Faecal samples were collected from 90 young geese in three age groups (5, 7 and 9 weeks old) in 2014. The geese were kept indoors on deep litter and pastured from spring to autumn. The area of the pastures around the buildings where the geese grazed was about 1 hectare, divided into quarters for different age groups. Before grazing, the birds were dewormed with fenbendazole (Fenbenat powder 4%, Naturan). As additional treatment for coccidiosis, coccidiostats were added to the feed. The study was conducted using the McMaster quantitative method with centrifugation (flotation liquid: NaCl and glucose). The birds were shown to be infected with coccidia and nematodes. The prevalence of Eimeria sp. infection (mean 40%) and the number of oocysts per gram of faeces (reaching 5,300 OPG) were highest in the youngest age group of geese. The level of Amidostomum anseris infection was similar in the three age groups, with prevalence from 40% to 50% (nematode egg output ranged from 50 to 350 eggs per gram of faeces, EPG). Capillaria anatis was observed only in 5- and 7-week-old geese.

Applicability of anatid and galliform microsatellite markers to the genetic diversity studies of domestic geese (Anser anser domesticus) through the genotyping of the endangered zatorska breed.

BACKGROUND: The 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. FINDINGS: Thirty-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. CONCLUSIONS: We 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.

Generation of cloned and chimeric embryos/offspring using the new methods of animal biotechnology.

The article summarizes results of studies concerning: 1/ qualitative evaluation of pig nuclear donor cells to somatic cell cloning, 2/ developmental potency of sheep somatic cells to create chimera, 3/ efficient production of chicken chimera. The quality of nuclear donor cells is one of the most important factors to determine the efficiency of somatic cell cloning. Morphological criteria commonly used for qualitative evaluation of somatic cells may be insufficient for practical application in the cloning. Therefore, different types of somatic cells being the source of genomic DNA in the cloning procedure were analyzed on apoptosis with the use of live-DNA or plasma membrane fluorescent markers. It has been found that morphological criteria are a sufficient selection factor for qualitative evaluation of nuclear donor cells to somatic cell cloning. Developmental potencies of sheep somatic cells in embryos and chimeric animals were studied using blastocyst complementation test. Fetal fibroblasts stained with vital fluorescent dye and microsurgically placed in morulae or blastocysts were later identified in embryos cultured in vitro. Transfer of Polish merino blastocysts harbouring Heatherhead fibroblasts to recipient ewes brought about normal births at term. Newly-born animals were of merino appearance with dark patches on their noses, near the mouth and on their clovens. This overt chimerism shows that fetal fibroblasts introduced to sheep morulae/blastocysts revealed full developmental plasticity. To achieve the efficient production of chicken chimeras, the blastodermal cells from embryos of the donor breeds, (Green-legged Partridgelike breed or GPxAraucana) were transferred into the embryos of the recipient breed (White Leghorn), and the effect of chimerism on the selected reproductive and physiological traits of recipients was examined. Using the model which allowed identification of the chimerism at many loci, it has been found that 93.9% of the examined birds were chimeras. The effect of donor cells on the reproduction and physiology of the recipients was evident.

Age effect of broiler breeders on fertility and sperm penetration of the perivitelline layer of the ovum.

The objective of this study was to determine the age effect of a broiler breeder flock on duration of fertility and number of spermatozoa penetrating the perivitelline layer overlying the germinal disc (SP/mm(2) GDIPVL). Moreover, in the second half of the flock's reproductive life, the effect of using ejaculates of young roosters (CA2) in artificial insemination (AI) on the above parameters of fertility was estimated. The commercial flock of broiler breeder hens (n = 100) was inseminated six times from 31 to 62 weeks of age. Additional inseminations, with ejaculates of roosters aged 31 and 36 weeks (CA2), were performed at 56 and 62 weeks of age. AI was performed during two consecutive days (D0 and D1) with an insemination dose of 125 x 10(6) spermatozoa/0.06 ml containing pooled ejaculates. The following parameters were studied: the effective and maximum duration of fertility (De and Dm), percent of fertility on different days after AI (FD10, FD15 and FD20), indices of duration of sperm penetration (DSP, SP < or = 3/GDIPVL), SP/mm(2) GDIPVL in eggs laid on successive days after insemination of hens at different age, and correlations between some fertility indices. Both for De and Dm, the highest values were noted after AI of the layers at 36 weeks of age (14.8 +/- 0.49 and 17.4 +/- 0.46 days, respectively), which were about 2 days longer than at 56 weeks. All fertility indices decreased gradually with age, starting from AI at peak egg production (31-36 weeks of age), while the use of ejaculates from CA2 did not help to increase them significantly. Correlation coefficients between SP/mm(2) GDIPVL and the other fertility indices were positive and highest for eggs laid on D3. It is concluded that high De values can be obtained from broiler breeders in adequate environmental and technological conditions of AI. It is suggested that the age-related decrease in fertility is more pronounced in females, in which the efficiency of sperm storage tubules decreases. The present fertility indices indicate the possibility of lengthening AI intervals, especially at peak egg production.