Effect of seasonal infertility period on boar sperm proteins and quality characteristics

ΔΕΝ ΔΙΑΤΙΘΕΤΑΙ ΠΕΡΙΛΗΨΗSwine seasonal infertility reduces the productivity and profitability of a pig farm. The main causes of this condition are elevated environmental temperatures and long photoperiod during the summer season. The aim of this study was to investigate which sperm proteins and parameters are affected during the period of seasonal infertility. Depending on the environmental temperatures, the period from October to June was considered as cold and the period from July to September as warm season. A total of 65 ejaculates from 18 boars were collected over a year. Each semen sample was evaluated for kinetics (Computer Assisted Semen Analyzer), morphology (Sperm Blue stain), viability (Propidium Iodide - Calcein AM stain), mitochondrial membrane potential (Rhodamine 123 – Propidium Iodide stain), membrane integrity and functionality (Hypo-osmotic swelling test) and sperm DNA integrity (Acridine Orange Test). Moreover, selected proteins (HSP90, GPX5, OPN) were detected and quantified. The kinetic parameters VSL, LIN and the midpiece abnormalities were significantly higher in the warm compared to the cold season (p<0.05), while a strong tendency towards higher values for HSP90 and GPX5 was observed in warm compared to cold season (p=0.07and p=0.06, respectively). In conclusion, among the boar sperm characteristics tested in our study, seasonal infertility period negatively affected VSL and LIN kinetics, while GPX5 seminal plasma enzyme and HSP90 sperm surface protein increased their sperm protective effects

The Phenotype Variability, of the Racka Sheep in the Republic of Serbia

ΔΕΝ ΔΙΑΤΙΘΕΤΑΙ ΠΕΡΙΛΗΨΗThe intensification of sheep production, by permanent genetic selection and the development of breeding technology, has led to the creation of highly productive sheep breeds. In this way, many highly productive breeds were created which could demonstrate their high production potentials only under perfect conditions of nutrition, accommodation and care. Preservation of indigenous breeds is of great importance in order to protect and safeguard those breeds and, in this way, it is possible to restore some of the characteristics that are lost during intensive selection, which are mostly related to resistance. The Racka sheep (Serbian: Vitoroga žuja) is considered to be an autochthonous breed and a genetic resource in the Republic of Serbia. As a primitive breed with low productivity, it offers no economic profitability and, thus, there is no great interest in its breeding. According to the FAO data from 2008-2014, the number of these sheep ranges from 500 to 1000. The objective of this study was to determine the phenotypic variability and to assess the external measurements of the Racka sheep. One-hundred fifty Racka breed ewes were included in this study. The effects of three farms on the phenotypic characteristics and their body indexes were calculated. The significance of the research is reflected in the advancement of this breed and in the assessment of the possibilities of selection work in these herds