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The aim of this work was to determine the activity of the akrosin inhibitor on the basis of depressing the tripsin activity of polar fox (Alopex lagopus) semen and to follow the changes that affect these properties throughout the whole reproductive season. Additionally, the molecular forms of the inhibitor were electrophoretically separated. The research covered 126 ejaculates obtained manually seven times from 18 polar foxes (at intervals of 10-12 days). The highest inhibitor activity was observed in the seminal plasma from the ejaculates obtained in the first sample, the lowest results were characteristic of the fifth sample. The lowest activity of the akrosin inhibitor, determined on the basis of depressing the tripsin activity, indicates either the weakest protection of the semen proteins along with the whole reproductive system from the influence of the akrosin devoid of damaged acrosomes or the already initiated process of proteolysis.
Habitat composition of breeding territories, habitat use during foraging, and nest-site selection of the Great Grey Shrike Lanius excubitor were examined in western Poland during years 1998-1999. Meadows and spring crops occurred within territories more frequently than expected by their availability. Habitat utilisation during foraging was significantly non-random and shrikes appeared to prefer low vegetation. All of 27 nests were located along tree lines and edges of small woodlots (maximum 7 m), and neither deciduous nor coniferous trees were preferred (78% and 22%, respectively). Preferred habitats of Great Grey Shrikes are relatively uncommon in modern agricultural landscape. Lack of suitable habitats in intensively used farmland may be the most important reasons for shrike population decline over Europe. Wielkopolska region offers good breeding habitats and this species has more dense and stable population over here, than in other parts of Europe.
Badania prowadzono na 6 ogierach rasy konik polski w wieku średnio 7 lat, wadze ciała 380- 410 kg, w czasie 7 miesięcy (grudzień-czerwiec), w dwóch sezonach kopulacyjnych. Dieta ogierów zawierała: 21.82 mg Zn , 7.20 mg Cu i 136.92 mg Fe w kg s.m. paszy w I sezonie, a 17.53 mg Zn, 6.50 mg Cu i 130.55 mg Fe w kg s.m. paszy w II sezonie. W czasie badań oznaczano stężenie Zn, Cu i Fe w surowicy krwi i osoczu nasienia. Badania wykazały istotne miesięczne zmiany w stężeniu Zn, Cu i Fe w surowicy i osoczu nasienia ogierów w obu sezonach kopulacyjnych.
In connection with scarce publications on the qualities of polar fox semen and the mutual relationship between particular features of the semen, the undertaken research aimed at specifying selected polar fox semen indicators and determining possible mutual correlations between them. The semen for analysis was collected 7 times from 18 foxes during the period of their sexual activity. In total, 126 ejaculates were obtained and they underwent detailed assessment. The total ejaculate bulk was determined as well as mass spermatozoa movement, the proportional share of hyperactive spermatozoa (preceded by sperm rotation in the percoll’s gradient), ejaculate pH, fructose concentration, the proportional share of spermatozoa not connected with antisperm antibodies and the proportional share of spermatozoa characterized by structural differences. Additionally, the interdependence between the semen quantity and quality and the breeding effectiveness of the analyzed foxes was examined and assessed. The results of the research indicate the high biological quality of the semen investigated during the whole breeding period, which led to high breeding results. The interdependence between the over all effectiveness of the analyzed specimens and the spermatozoa movement, and the proportional share of hyperactive - i.e. ready to fertilize - spermatozoa was observed. This indicates that separating spermatozoa in the percoll’s gradient as a method of spermatozoa preparation allows for in vitro selection of specimens of the best qualities and is useful in case of applying insemination.
The aim of the study was to evaluate the morphology structure of sperm cells and quality of individual male deer obtained in the Lublin Upland during the 2015/2016 hunting season. The comparison included two separate periods of the hunting season resulting from varying physiological processes related to the estrus period of this species. In the first study with regards to the estrus period, males were characterized by an average of 1.6 grams less testicle weight, while body weight was 1.9 kg higher. Increasing the mass of the testicles in the reproductive season proceeded simultaneously with the increase in the share of properly developed sperm cells to the level of 70.6%. During the pre-estrus period, the percentage of spermatozoids with main and secondary defects accounted for almost 60%. Between the compared periods, an approximately 6.8% body weight loss occurred. The highest percentage of properly developed spermatozoids was present in deer aged 4 and 5 years. Regarding the greatest body weight loss in these two age groups, it is indicated that this age is the climax in terms of potential accession to the breeding and effective mating of females and the possibility of fertilization. Analysis of the relationship between body weight and testicle weight showed low and statistically insignificant correlation coefficients (rxy = 0.331-0.393) between those features.
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