Ograniczanie wyników

Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 20

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  body
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Characterisation of salmon (Salmo salar) aged 0+, 1+, 2+, stocked in Pomeranian rivers, involved 25 plastic and 13 meristic characters, the opercular bone arrangement, and coloration. Coloration of body and fins, appearing at the age of 0+ at the fork length of 6-10 cm belonged to the earliest species-specific traits. Typical values of certain species-specific characters, such as tail base width, caudal fin incision (as per cent of l. caudalis), and the length of the upper jaw (as per cent of l. capitis) were recorded as early as in the fish aged 0+. Other characters, such as the opercular bone arrangement, were observed in those individuals aged 1+ and only in some fish aged 0+. The typical salmon anal fin shape occurred in some of the salmon aged 1+ and 2+ only. The study showed a high variability and significant differences in meristic and plastic characters between individuals grown in various rivers.
The study was aimed at determining effects of feed ration on growth, within-group variability, and chemical composition of the body of juvenile zander (c. 25 g initial individual weight) grown out in a recirculation system for 42 days. The fish were fed a commercial pelleted trout feed offered at three rations (Group L: 1.2% of stock biomass; Group M: 1.6% of stock biomass; and Group H: 2.0% of stock biomass). Each experimental treatment involved two replicates. The feed rations used were found to significantly (p < 0.01) affect fish growth: the mean body weight on termination of the experiment was 47.9, 60.3, and 69.4 g in Group L, M, and H, respectively. Statistically significant differences were revealed also in SGR and fish condition. The most favourable food conversion ratio (FCR) and protein efficiency ratio (PER) were found in Group M, the between-group differences being significant as well (p < 0.05).
The procedures for GMO safety tests include traceability of transgenic protein and transgenic DNA if the plant constitutes a component in the diet for an animal. This is due to the possibility of horizontal transfer of genes, accumulation of transgenic DNA in consumer’s organs, or induction of antibiotic resistance in gastrointestinal tract microflora. The last possibility is related to the use of marker genes in the process of transformation. In an in vivo experiment conducted on laboratory rats with the use of transgenic cucumbers expressing the pre-prothaumatin gene, the presence of transgenic DNA in the tissue of kidneys and liver was not detected. Resistance to neomycin of gastrointestinal tract microflora of the rats fed the GMO diet was not found, despite the use of marker genes (npt II) in the process of transformation of the investigated plants.
Male rats of Wistar strain (n = 48) were fed a vitamin A deficient diet for 3 days of adaptation period and then a 10 day experimental period to reduce slightly the body stores of this vitamin. Half of the animals were subjected to physical training and/or oral vitamin A supplementation. Four different doses of supplementation were used – 0, 7.5, 15 and 60 μg/d/rat, which is equivalent to 0, 25, 50 and 200 IU of vitamin A, respectively. Animals from the defined groups ran on a treadmill with a rate of 2.0 m/s for 15 minutes per day for 10 days. After overnight fasting, the rats were sacrificed, and insulin in blood serum and hepatic retinol concentrations were estimated. Daily feed intake and daily body gains were similar in groups of sedentary and physically trained rats. A moderate level of oral vitamin A supplementation (the highest supplemented dose was about 6 x the above recommended NRC level) did not cause any changes in these zootechnical parameters. Oral Vitamin A supplementation resulted in an increase in retinol concentration in the liver (F = 15.2, p < 0.001), but without significant difference between trained and untrained animals. Physical training of rats caused a statistically significant decrease of insulin concentration in blood serum (1.53 ± 0.18 vs. 1.73 ± 0.20). This difference was highly significant (F = 11.1, p < 0.001). Vitamin A supplementation was found not to influence the concentration of this hormone, which is responsible for energy metabolism regulation in the body. Based on estimated parameters, the necessity of vitamin A excessive use in physically trained subjects was not proven.
Studies were conducted on 77 tongues, collected from rabbits being at day 15, 18, 20, 22 and 26 of prenatal life and from rabbits at day 1, 15 and 30 and in the 6th month of postnatal life. Tissues for analyses, collected from the lateral surfaces of the body of the tongue of rabbits, were studied under a light microscope (LM) and a scanning electron microscope (SEM). The thickness of the epithelium in successive periods of pre- and postnatal life was analyzed morphometrically. As a result of the conducted studies it was shown that the epithelium covering the lateral surfaces of the tongue changes in the course of pre- and postnatal development from an epithelium consisting from 1-2 layers of cells into a nonkeratinized stratified squamous epithelium. The thickness of the epithelium increases in successive analyzed periods of life in rabbits. A rapid growth rate was found for the epithelium in the period from day 26 p.c. The lamina propria mucosae is observed in histological slides starting from day 22 p.c. In the same period the presence of elastic fibers was shown. Glycogen was found in the cytoplasm of the epithelial and mesenchymal cells from day 15 to 20 p.c.
The body of Multicalyx elegans consists of a dorsal main part and a ventral disc subdivided into compartments (alveoli) by transverse septa which carry pairs of “foot”-like lateral organs. The dorsal lip contains a groove with a large number of receptors. Numerous bulbous receptors and pits are also found in other parts of the body, which is covered by a tegument bearing densely packed microtubercles. Small particles associated with the body surface may represent viruses or bacteria.
The concentration of heavy metals in the bodies of invertebrates is dependent on their physiological equipment and prevalent environmental factors. To verify the effect of some of these factors on the content of metals (Pb, Cd, Zn, Cu, Mn) we analysed and then tested (using RDA, t-test) ten species of field ground beetles (Coleoptera, Carabidae). A significant effect of Cu and Cd was discovered in terms of the sex; the males accumulated more Cu (27.520 mg kg⁻¹) than females (18.297 mg kg⁻¹) (P <0.01), which, on the contrary, accumulated more Cd (1.495 mg kg⁻¹) than males (0.663 mg kg⁻¹) (P <0.02). The content of all the metals differed significantly (P <0.03) according to the species, unambiguously showing species-specific models of accumulation. The effect of the feeding ecology was evident only on the essential elements; carnivores (Zn – 222.596 mg kg⁻¹, Cu – 27.211 mg kg⁻¹, Mn – 71.929 mg kg⁻¹) had a significantly (P <0.03) higher contents than omnivores (Zn – 168.198 mg kg⁻¹, Cu – 21.116 mg kg⁻¹, Mn – 58.452 mg kg⁻¹). Although there were differences (P <0.01) in the concentrations of Zn and Cu between the spring (Zn –163.749 mg kg⁻¹, Cu – 19.998 mg kg⁻¹) and autumn (Zn – 202.373 mg kg⁻¹, Cu – 25.496 mg kg⁻¹) species, the effect of the type of reproduction is considered to be only partial. At the same time the time of sampling affected the Zn and Mn (P <0.02) content. An important positive correlation was determined between the contents of Cu-Zn, Mn-Zn and Mn-Cu.
Stephanoprora podicipei sp. n. parasite of great grebe Podiceps major Boddaert, 1785 (Aves, Podicipedidae) from Mar Chiquita coastal lagoon (Buenos Aires, Argentina) is described and illustrated. The new species presents common features with S. conciliata Dietz, 1909; S. manei Holcman-Spector et Olagüe, 1986; S. dogieli Holcman-Spector et Olagüe, 1989 and S. uruguayense Holcman-Spector et Olagüe, 1989. S. podicipei sp. n. can be clearly distinguished from these species, principally, by the smaller size of its body, peristomic disk, testes, ovary and by its shorter oesophagus and uterus. S. podicipei also differs from S. argentiniensis Sutton et al., 1982, the other species of this genus parasitizing Podiceps major in Argentina, in the number of spines of the peristomic disk (22 vs. 20), in its smaller body, peristomic disk and testes; in its larger acetabulum and eggs, in the shape of the testes and in its vitellaria extending to the middle of the anterior testis.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.