Wydanie 340(45)1 2018

Stały URI dla kolekcji

https://oa.zut.edu.pl/handle/20.500.12539/699

Przeglądaj

Przeglądaj Wydanie 340(45)1 2018 wg Temat "bydło"

Teraz wyświetlane 1 - 2 z 2
  • Miniatura
    PozycjaOpen Access
    The Association Between Erα/ Bgli Genotypes and Milk Performance in Holstein-Friesian and Jersey Cattle. Preliminary Study
    (Wydawnictwo Zachodniopomorskiego Uniwersytetu Technologicznego w Szczecinie, 2018) Wasilewska, Małgorzata; Tabor-Osińska, Sara; Department of Molecular Cytogenetics, West Pomeranian University of Technology, Szczecin, Poland; Department of Molecular Cytogenetics, West Pomeranian University of Technology, Szczecin, Poland
    Modern farming asks many questions which science has answers to. While selecting animals for further breeding, many aspects should be taken under consideration, like an animal's phenotypic and genetic features. Marker-assisted selection is a useful tool for judging an animal's genetic value. There are many well-known genetic factors responsible for efficiency of animal production and many of which still need to be studied in more depth. The following study examines the association between ERα/ BglI genotypes and milk performance in cattle. Two breeds were analysed in this study (Jersey and Holstein-Friesian red and white) and from the data gathered there is evidence to suggest that polymorphisms in the gene influences milk yield in these breeds. Three genotypes were identified: GG, AG, AA. The data pertaining to milk yield of both herds received from the farmers shows that the efficiency of milk production is the highest in the GG homozygotes and the lowest in the AG heterozygotes. This suggests a strong link between these genetic variants and the effective production of milk. However, to confirm the association between the polymorphic traits of the studied gene and milk production traits, it would be necessary to run a study on a larger group of cattle and to use infomration about their further lactation cycles.
  • Miniatura
    PozycjaOpen Access
    Influence of the Degree of Ejaculate Dilution on the Results of the Assessment of Motility of Sperm of Breeding Bulls Obtained by Two Methods
    (Wydawnictwo Uczelniane Zachodniopomorskiego Uniwersytetu Technologicznego w Szczecinie, 2018) Mizera, Alicja; Kuczaj, Marian; Institute of Animal Breeding, Wrocław University of Environmental and Life Sciences, Poland; Institute of Animal Breeding, Wrocław University of Environmental and Life Sciences, Poland
    The experiment carried out aimed to examine the effectiveness of two methods of assessment of the parameters of sperm motility in thawed semen depending on the degree of its dilution. The semen was collected from 12 Simmental breeding bulls using an artificial vagina. Semen samples were pre-evaluated in terms of volume, colour, pH, viability, concentration and motility and then combined into one pooled sample to eliminate individual differences, cooled to 4°C, packed in 0.25 ml straw and frozen in liquid nitrogen, stored in a container at –196°C. Next they were thawed, divided into samples A, B and C, and subsequently diluted 1 : 10 (sample A), 1 : 20 (sample B) and 1 : 30 (sample C) and selected motion parameters were evaluated using conventional microscopic method and computer-aided (CASA). The obtained results were analysed statistically. The total sperm movement analysed by two methods in all tested samples differed significantly (p < 0.05). The spermatozoa progressive movement studied by the CASA system differed significantly from the one tested using the conventional method at dilution 1 : 20 and 1 : 30 (p < 0.05). The obtained results of the progressive movement at 1 : 10 dilution using both methods did not differ significantly. Studies have shown that mobility analysis carried out using the CASA system was characterized by greater accuracy and reproducibility of results than the conventional microscopic method. Moreover, the results of the following studies indicate the relationship between the degree of sperm dilution and the reproducibility of results.