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Data from 75 bird species weighing between 6 g and > 16 kg confirmed a supposition that the amount of haemoglobin per unit surface area of erythrocyte was not dependent on body mass. It showed a constancy across the range reflecting adjustment of the total surface area of erythrocytes in relation to blood haemoglobin concentration. This conclusion is based on an inverse correlation between the numbers and sizes of red blood cells.
The comparative studies were performed on insulin receptors of erythrocytes and liver plasma membranes in fish (tench and carp) and bird (duck). The Scatchard plots indicated the presence of two pools of binding sites both in fish and duck. These pools show inter-species differences in binding ability and the number of receptors. Specific binding of insulin and the binding affinity are higher in duck than in fish.
The work was carried out in the villages of the Łomianki commune near Warsaw, Poland (52°20'N, 20°50'E) in 1994 and 1995. From among 315 clutches of Tree Sparrows studied, 20 exhibited one-day interruptions in the laying of first and second broods, while 2 were characterised by two-day interruptions. Amongst third broods, there was just a single one-day interruption noted in each year of the study. Interruptions did not occur immediately prior to the laying of the last egg in a clutch. Only in the case of the first brood in 1995 could a period of cold account for interruptions; in the remaining cases, the phenomenon must have been influenced by non-meteorological factors. The Tree Sparrow resembles the House Sparrow Passer domesticus in having far fewer interruptions to laying than other small hole-nesting birds, such as tits Parus spp. This is probably a reflection of the genus Passer having evolved in dry areas, where the accumulation of body reserves in the female prior to laying is an adaptation reducing the length of the breeding period to match the time associated with the rainy season, when food is abundant.
Eighty cormorants from the area of Ostroda and Mrągowo were used for this study. The analyses were carried out between 1993-1996. Each year 10 two-year-old birds were shot (5 females and 5 males) in two nesting grounds. On average, the amount of concentrated DDT in cormorant liver fat was 4.914 mg/kg and y-HCH was 0.039 mg/kg of wet mass. The average amount of DDT in subsequent years varied and ranged from 2.515 to 7.252 mg/kg; however, the differences were statistically insignificant. The females accumulated higher levels of DDT than the males, on average up to 8.796 mg/kg. The differences in DDT amounts concentrated in liver fat of both cormorant groups in different years appeared to be insignificant. Liver concentrations of γ -HCH in the observed period most frequently showed tendency to increase, from the level of 0.012 in 1993 to 0.106 mg/kg in 1995. This value decreased in 1996 to 0.003 mg/kg. Higher amounts of γ-HCH in liver fat were recorded in birds originating form the Mrągowo area, excluding the individuals shot in 1995. It was shown that the males accumulated higher levels of γ -HCH in their livers than the females (years 1993, 1994 and 1996). The presented study shows the continuous threat of the analyzed xenobiotic agents to water fowl and the need for continuous monitoring of water fowl in respect of their intoxication by DDT and HCH.
The study was carried out from May 1988 to April 1993 in two types of tropical forests: the tropical evergreen and moist deciduous. The vertical distribution of birds and foliage abundance was recorded by visual observation in seven height classes, using the line transect method. The vertical distribution of 94 bird species was recorded in evergreen forest, and of 90 in moist deciduous forest. Bird species richness and the numbers of birds were highest in the stratum from 1 to 5 m in both the evergreen forests (57 species) and the moist deciduous forests (68 species). The species richness indices of birds in the two types of forest did not display such a clear relationship. Foliage abundance was high up to a height of 30 m in the evergreen forests, whereas in moist deciduous forests, foliage was abundant only up to 20 m. A significant positive correlation was obtained between foliage abundance and species richness and also between the numbers of birds in both types of forests. Significant correlation was also obtained between foliage abundance and the species diversity indices in the two types of vegetation.
The shooting of protected species, especially rare animals, is regarded as a priority issue by law enforcement authorities. In such cases, an expert veterinarian is required not only to confirm the death of the animal as a result of shooting, but also to provide a precise description of the shot. In cases of shootings with pellet bullets, such a description is particularly difficult. The evaluation of the gunshot wounds of an osprey (Pandion haliaetus) delivered to the Veterinary Medical Centre at the University of Poznań called for the use of a variety of diagnostic techniques. A preliminary assessment confirming the shot was based on an X-ray photo. Computed tomography (CT) was used for in-depth diagnostics, providing a spatial representation of bullet stopping points and fragments. The shot caused a lower leg bone fracture. This damage upset the anatomical structure of the animal’s limb, which made it impossible to establish the wound channel by CT. Therefore, full shot characteristics could only be made only after a classical post-mortem examination. This examination facilitated the use of modern imaging diagnostic techniques. The use of mixed diagnostic techniques enabled us to determine the number of shots, the type of ammunition used and the direction from which the shot was fired. On the one hand, this case illustrates the possibilities offered by modern imaging diagnostic techniques and, on the other hand, it shows that the classic post-mortem examination remains a primary diagnostic tool for veterinary forensic experts. This is especially important when preparing forensic veterinary opinions in high-priority law enforcement cases.
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