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Abstract

Biological invasion as one of the main threats to natural ecosystems has big economic impact on conservation of nature. Studies of the population biology of invasive species may allow more precise focus on specific plant and soil characteristics involved in invasiveness. The aim of the study was to investigate the relationship between selected biological population characteristics of Impatiens parviflora and a few chosen chemical and physical soil features. Sites were selected because of the poor mapping of invasive plants in the protected natural areas and their interactions with specific soil characteristics. Research on I. parviflora was realised during a vegetation season in three forest nature reserves in Prešov district, Slovakia. Some population biological characteristics of I. parviflora as one of the most invasive plant species in Slovakia and Central Europe were surveyed. The correlation between the numbers of plants was analysed, as well as select population biological characteristics of I. parviflora (plant height, width of the largest leaf and the number of flowers/fruits) on some select chemical and physical soil attributes (soil pH, bulk density, porosity and soil moisture) were analysed. The results suggest that biological characteristics of I. parviflora in three different microhabitats – a meadow (a habitat without tree vegetation), a habitat close to the stumps and a habitat under dense tree vegetation seemed to influence the selected soil parameters. Our results showed that I. parviflora prefers acidic and non-compacted soil conditions. Sunlight and soil moisture do not show statistically significant differences on any biological characteristic of the population. The results also suggest that the autecology of I. parviflora in Western and Central Europe is not very well known and deserves further study.

., Filipiak J., Przybył A. 2002 - Biological characteristics of vendace ( Coregonus albula ) from the Tuczno Wielkie and Siecino lakes - Sci. Pap. Agric. Univ. Pozn. Anim. Sci. 4: 77-90. Dąbrowski B., Eichler M. 1972 - The effect of the course of temperatures on fluctuations of Coregonus albula Linnaeus production - Rocz. Nauk Rol. 94-H-2: 59-73 (in Polish). Dąbrowski K., Czesny S., Matusiewicz M. 2002 - Coregonids - In: Nutrient requirements and feeding of finfish for aquaculture (Eds) C.D. Webster, C.E. Lim. Cabi Publishing, New York, 230-244. Demska-Zakęś K., Długosz M

Chemical and Biological Characteristics of Different Hydrated Monocalcium Phosphates for Broiler Chickens

Three hydrated monocalcium phosphates differing in purity (with or without monetite, or monetite and calcite) and in crystalline structure were used in broiler chickens diets. The performance indices, concentration of Ca, P and Mg and activity of alkaline phosphatase in blood plasma, the content of these mineral elements in bones, and physico-mechanical parameters of femur and tibia bones were recorded. Body weight on 35th day of life, feed intake and mechanical parameters of bone quality were slightly affected by the type of phosphates used. Higher Ca and P concentration in blood was stated in chickens fed diets with greater purity of phosphates, but activity of alkaline phosphatase has increased with the admixture of monetite or calcite used in phosphates. The best parameters of bone quality were found in the treatment in which hydrated monocalcium phosphate (MCP) with admixture of monetite and calcite was applied. Higher concentration of both Ca and Mg in bone was determined in chickens fed diets with pure phosphates.

Abstract

“Wartowice” tailings pond was closed in 1989, resulting in 232,4 ha tailings pile requiring reclamation. The major problem is heavy metals presence and poor nutrient conditions and physicochemical structure of soil which disturbs the plants development. In order to assess the real condition of studied area the complete biological characteristic has been done. The physicochemical conditions were assessed altogether with phytosociological, microbiological and toxicological studies of deposits. We recorded only 27 species of vascular plants belonging to 15 families on the tailings pond of which 5 belong to Rosaceae, 4 to Asteraceae and 3 to Poaceae and Saliceae. Species inhabiting the tailings depended on their dispersal capacity, metal tolerance and rhizome strategy. Microbiological analyses revealed the low number of bacteria and fungi on the tailings pond, apart from the small uplift area where the plants were indentified. Bacteria identified on the tailings pond were classified to 8 genera. The low number of bacteria suggests the lack of nutrients which affects the development of soil microflora. Toxicity tests showed that post-flotation sludge is not toxic to microorganisms because of its high pH. Some plants, such as lucerne could even influence positively the microorganisms development what has been proved in our studies. The tailings toxicity was higher towards producers, where Secale cereale appeared to be the most sensitive species. Amendment with topsoil from adjacent areas can influence positively the phytotoxic properties of tailings and enrich them into native seeds.

Sea of Azov fish and their food resources - ICES J. Mar. Sci. 57: 641-648. Smirnov A.I. 2001 - The round goby Neogobius melanostomus (Pisces, Gobiidae) is found outside of its area: reasons, distribution rate, probable after-effects - Vestn. Zool. 5: 71-77 (in Russian). Tkachenko M.Yu., Demchenko N.A. 2014 - Diet composition of round goby (Neogobius melanostomus (Pallas, 1814) under different ecological conditions - Mar. Ecol. J. 4: 64-70 (in Ukrainian). Tkachenko M.Yu., Demchenko V.O. 2015 - Biological characteristics of round goby Neogobius melanostomus (Pallas

Abstract

The paper contains new data, which confirms distribition of the ratan goby, Ponticola ratan (Nordmann, 1840), in fresh waters, as well as its diagnosis, description, and brief information on its biology.

Abstract

The aim of this study was to determine the growth features of European perch (Perca fluviatilis L., 1758) inhabiting Lake Ladik. A total of 858 individuals were caught. The total length and weight ranged from 8.2 to 27.5 cm and from 7.16 to 365.20 g, respectively. The age of the females ranged between 1 and 7 years and the age of the males ranged from 1 to 5 years. The female to male ratio was 1:0.19. The von Bertalanffy growth equation parameters were determined as L =41.27 cm, W =1251.40 g, K=0.10 (year−1), t 0 (year)=−1.98 for all samples. Length-weight relationship was calculated as W=0.0047TL 3.358 for all specimens. Length-length relationships (total length-standard length, total length-fork length, standard length-fork length) were highly significant (r2>0.98). The mean condition factor value was obtained as 1.28 for all fish. Condition factor showed statistically significant increase according to length classes.

Abstract

Morphological characteristics were studied in adult and embryonic Amidostomum anseris (Zeder, 1800) obtained from domestic goose Anser anser domesticus Linnaeus, 1758. The studied characters included species-specific morphometric indices of male and female specimens and differential characters of sex-related dimorphism in that species. Stages and periods of embryonic development, and viability of the nematodes were studied at laboratory conditions. Size dimorphism in A. anseris was considerable, females were significantly larger (by 10.09–27.98 %) than males by 11 parameters. Additional metric characters were proposed to enhance effectiveness of differentiation of female and male A. anseris specimens. Under laboratory conditions, embryonic development of A. anseris occurs in four stages: blastomere cleavage; larval formation; formation of non-infective larvae I and II; formation of infective larva III which hatches from the egg. Infective larvae develop at 23 °С in six days, and their viability was up to 78.33 ± 2.08 %.

In blood of frogs in two of seven studied biotopes the presence of the genus Hepatozoon representatives was revealed. Morphometric parametres allowed defining a specific accessory of the revealed haemoparasite Hepatozoon in a blood channel of village Malozaharino frogs which were closest to the species H. magna (Grassi et Feletti, 1891) Labbe, 1899

Abstract

Hepatitis E virus (HEV) is transmitted mainly through food and water sources. HEV is a major public health problem faced by developing countries. HEV causes large outbreaks of hepatitis E (HE) or acute sporadic infection. HEV can also lead to chronic infection. HEV mainly affects the young, middle-aged people, and pregnant women, who especially display high rates of infection. This study reviews HE while considering its biological characteristics, clinical symptoms, epidemic characteristics, vaccine, and detection methods.