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Abstract

The purpose of this study is to describe the current state of tidewater glaciers in Svalbard as an extension of the inventory of Hagen et al. (1993). The ice masses of Svalbard cover an area of ca 36 600 km2 and more than 60% of the glaciated areas are glaciers which terminate in the sea at calving ice-cliffs. Recent data on the geometry of glacier tongues, their flow velocities and front position changes have been extracted from ASTER images acquired from 2000-2006 using automated methods of satellite image analysis. Analyses have shown that 163 Svalbard glaciers are of tidewater type (having contact with the ocean) and the total length of their calving ice-cliffs is 860 km . When compared with the previous inventory, 14 glaciers retreated from the ocean to the land over a 30-40 year period. Eleven formerly land-based glaciers now terminate in the sea. A new method of assessing the dynamic state of glaciers, based on patterns of frontal crevassing, has been developed. Tidewater glacier termini are divided into four groups on the basis of differences in crevasse patterns and flow velocity: (1) very slow or stagnant glaciers, (2) slow-flowing glaciers, (3) fast-flowing glaciers, (4) surging glaciers (in the active phase) and fast ice streams. This classification has enabled us to estimate total calving flux from Svalbard glaciers with an accuracy appreciably higher than that of previous attempts. Mass loss due to calving from the whole archipelago (excluding Kvitřya) is estimated to be 5.0-8.4 km3 yr-1 (water equivalent - w.e.), with a mean value 6.75 ± 1.7 km3 yr-1 (w.e.). Thus, ablation due to calving contributes as much as 17-25% (with a mean value 21%) to the overall mass loss from Svalbard glaciers. By implication, the contribution of Svalbard iceberg flux to sea-level rise amounts to ca 0.02 mm yr-1. Also calving flux in the Arctic has been considered and the highest annual specific mass balance attributable to iceberg calving has been found for Svalbard.
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Abstract

The aim of this study was to compare effect of combinations of intravenous isotonic sodium bicarbonate (NaHCO3), acetate Ringer, lactate Ringer and small-volume hypertonic sodium chloride (NaCI) solutions along with oral electrolyte solutions (OES) on the treatment of neonatal calf diarrhea with moderate dehydration and metabolic acidosis. Thirty-two calves with diarrhea were used in the study. Calves were randomly assigned to receive acetate Ringer solution (n=8), lactate Ringer solution (n=8), isotonic NaHCO3 (n=8) and 7.2% saline solutions (n=8), and two liters of OES were administrated to all calves orally at the end of intravenous administration. Blood samples for blood gas and biochemical analyses were collected at 0 hours and at 0.5, 1, 2, 4, 6 and 24 hours intervals. All the calves had mild to moderate metabolic acidosis on admission. Increased plasma volume and sodium concentration, but decreased serum total protein were observed within 0.5 hours following administration of hypertonic 7.2% NaCI + OES, compared to other 3 groups. In conclusion, administration of intravenous hypertonic 7.2% NaCI solution in small volume along with OES provided fast and effective improvement of dehydration and acid-base abnormalities within short time in treatment of calf diarrhea with moderate dehydration and metabolic acidosis.
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Abstract

Perinatal calf mortality in dairy herds has been reported worldwide. The etiology of stillbirth is multifactorial, and can be caused by various species of bacteria and environmental factors. Among them some potential pathogens from the Mollicutes class such as Mycoplasma (M.) spp. and Ureaplasma (U.) diversum can be isolated from the bovine genital tract and other organs of the suspected cattle. The aim of this study was to evaluate if the bacteria belonging to the Molli- cutes class i.e. M. bovis, M. bovigenitalium, M. canadense, M. canis, M. arginini, M. bovirhinis, M. dispar, M. alkalescens and U. diversum could have an impact on perinatal calf mortality in selected Polish dairy farms. The material was: 121 stillborn calves (SB), 21 live born calves (C) and 131 cows (dams) from 30 Polish Holstein-Friesian herds. Samples were examined from all the SB calves’ and six control euthanized calves’ abomasal contents and lung samples collected during necropsy, and from the dams’ serum and placenta. In dams the serological ELISA, and in calves and placenta samples molecular PCR/denaturing gradient gel electrophoresis, methods were used. Screening of dams’ sera for antibodies to M. bovis (ELISA) showed seven dams positive for M. bovis, whereas none of the nine examined Mollicutes microorganisms were detected in the placenta and calves.
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Abstract

The study was performed on 21 H-F calves divided into 3 groups of 7 animals each. The first group was composed of calves whose mothers did not receive an injection of Se preparation. The second and third groups consisted of calves whose mothers were administered injections of Se and vitamin E in a single dose of 10 ml and 30 ml, 10 days before the expected parturition date. 24 hours after birth, blood samples were collected from all calves to determine Se, Fe and IgG concentrations and the activity of GSH-Px and GGT. The results of the study indicate that the administration of a single-dose Se supplement to cows in late pregnancy increases Se concentration in calves and promotes passive transfer of immunity from the mother to offspring.
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