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  • The age and the growth of the european weather loach (Misgurnus fossilis)
    37-44
    Views:
    411

    The possibilities of examination the growth of fish species are  verry difficult, and much of methods are oblique. With the weather loach is the work especially complicated through the small scales. Till now the growth of weather loach is in Hungary unexamined.
    We applied self developed catch method in three explored channel. The length and weight measured on the fishes alive, as well the sexing. We analysed the datas with Bertalanffy-method.
    The growth of the fishes is different, but the growth of the body length was nearly the same in the three channels. The one year old fishes can growth to a maximum of 130-140 millimeters, the two years old fishes can growth to maximum of 180-190 millimeters. Longer fishes by 180-190 millimeters are 3 or more years old. The data of sex-ratio is deviant than the literature wroted. The fish from Fényes are growing faster, than the others. This species can be 190-200 millimeters long after 2 years from birth. It is a very fast growing.

  • Comparison of Reproductive Performance of the Roe Deer (Capreolus capreolus, L.) Among Different Regions
    41-46
    Views:
    220

    The potential and actual number of offspring of roe deer and the difference between these figures (prenatal and postnatal loss) significantly vary in each population yearly. The objective of this study is to examine the potential and actual number of offspring, the number of losses, and to find a link between the most important biological characteristics of does (body weight – BW, condition – KFI) and the number of raised offspring on four territories on the Great Hungarian Plain.
    Where the number of corpora lutea (CL) is the highest, there the losses are the highest as well, and the number of raised offspring is the lowest (region I.). Here, the rearing loss is double that of the weakest territory (region IV.). Rearing losses can be associated with the fenotype of does (BW, KFI) but environmental factors also have determinative importance. Where the number of twin-calving does was the highest, I found four times more does without a fawn than where the number of twin-calving does was the lowest. The nursing success was the best (the losses were lowest) in the region where the potential offspring (number of CL) was also the lowest, but the coverage of the habitat and the proportion of forests were largest. The food supply for the animals in autumn and winter are not enough, the structure of the habitat has to be improved as well, so that it might become adequate for game protection in extreme weather conditions.
    The results have to be considered as preliminary ones. It is essential to continue and extend the research to increase the reliability of the results.

  • Comparison of major population parameters of Brown hare (Lepus europaeus, Pallas 1758) in two hunting fields of the Great Hungarian Plain
    69-74
    Views:
    400

    Hungarian stock of game is not only part of our national treasure but also one of our domestic products and economic income. Not indifferent therefore the number and the state of health of our wildlife. Population decline of the Brown hare (Lepus europaeus, Pallas 1758) (one of our most important small game in Hungary) takes a long time. Demographic parameters of Brown hare was examined, particularly the factors affecting the decline of the species in Hungary. We took samples from typical habitats where the Brown hare could be found in relatively high density in our country. The article reports data of reproductive characteristics, diseases, parasites of Brown hare and other factors such as climatic and anthropogenic which could influence of the population dynamics. We mention sample collection and processing methods eg: population size estimates, examination of reproductive organs, the sex ratio and the age structure as well as the individual condition based on data of domestic and foreign authors and our partial results.

  • Investigation of intersexual polled goats
    11-15
    Views:
    355

    The sex reversal may occur in all mammalian species, but is connected to a favourable trait – the polledness – only in the goat. Later abnormal sex ratio was noticed in these goat populations, in which a part of the phenotypically male individuals was sterile. These males have two X chromosomes. In goats the PIS (Polled Intersex Syndrome) mutation is responsible for the absence of horns in homozygous and heterozygous individuals. This same mutation causes a female-to-male sex reversal, but only in the homozygous polled genetic female goats. The PIS mutation inhibits the expression of the FOXL2 gene which is responsible for ovary development, and a protein encoded by this gene inhibits the activity of the Sox9 gene. The Sox9 gene stimulates the development of the cells of the testis. When the FOXL2 gene is inhibited, the Sox9 gene is activated and transforms the ovary cells into testis cells. In our article we briefly introduce the morphological and chromosome investigations of three intersex individuals we found.