No abstract

The aim of the study was to establish concentration of selenium and the pertinent activity of glutathione peroxidase (GSH-Px ) in whole blood that could be used as reference values in future research. The first part of study was carried out on clinical healthy beef calves (n = 35), fed a basal diet and a ready-made fodder mix that contained 0.1 mg . kg -1 selenium. In the second part of our research, we investigated the GSH-Px activity in a group of calves (n = 47) that had not received supplements added to the basal diet. The research was carried out in the north-west Croatia, in the region known to be poorer in selenium. We determined GSH-Px activity in whole blood by the "Ransel" method adapted to a Technicon RA-1000 at 37 °C. Determination of Se concentration was done with a modification of the method given by Perkin-Elmer HGGS. The mean value of the Se concentration in the whole blood of the first group of calves was 200.22 ± 45.2 µg . l -1 and pertinent average GSH-Px activity was 764.6 ± 197.8 µkat . l -1 . From the results obtained, a correlation between Se and GSH-Px was calculated (r = 0.82; P < 0.001). The mean values of the GSH-Px activity in herd that did not receive a supplement were 435.3 ± 155.76 µkat . l -1 . Out of 47 animals of the second herd, four animals (8.51%) had lower values than those recommended as sufficient. This study confirmed that after the calculation of the correlation between Se and GSHPx, glutathione peroxidase activity determination can be used as a rapid and simple proxy for the determination of selenium concentration in whole blood.Glutathione-peroxidase, selenium, white muscle disease, beef cattle

Abstract. Haematological and biochemical parameters were examined in the blood of 87 cows, bulls and oxen of the indigenous Croatian breed, Istrian cattle. The sample represents 11.93 % of the total adult population. This breed is classified as highly endangered. The age of tested animals was between 2 and 17 years. Cattle were divided into three groups, animals aged 2 to 6 years (n=19), 7 to 10 years (n=37), and older than 10 years (n=31). Animals were kept in the area of Istria County, mostly in stables though occasionally at pasture. The cows were milked twice daily and gave an average of 1 000 litres of milk per year. Erythrocytes, leukocytes, haemoglobin, haematocrit and mean corpuscular volume were determined. Differential analysis was performed by counting blood cells in the blood smear after Pappenheim staining. Biochemical parameters such as total cholesterol, triglycerides, urea, creatinine, total bilirubin, calcium and inorganic phosphorus were determined. The activity of aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase was determined by spectrophotometry. These biochemical and haematological parameters of this Istrian breed were within the physiological range, while slight deviations were observed for certain parameters. The greatest deviation from the physiological range was shown in the concentrations of urea and creatinine. These results may contribute to a better understanding of the metabolic profile and haematological indicators for estimating the physiological status of these endangered cattle in Istria, for further investigation and for diagnostic purposes.

The concentrations of As, Cd, Cu, Hg, Pb and Zn were measured in four shellfish species (oysters, mussels, scallops, warty venus) collected along the Istria Peninsula coast during autumn 2013. Mean metal levels in shellfish ranged as follows (mg/kg): As 1.69-3.91, Cd 0.15-0.99, Hg 0.06-0.2, Pb 0.33-0.74, Cu 1.23-36.2, Zn 16.3-511. Statistical analysis showed a significant difference in As (p<0.05), Cd, Pb, Hg, Cu and Zn (p<0.01, all) levels among shellfish species. The highest metal concentrations were found in oysters (mg/kg): As 3.91, Cd 0.99, Cu 36.2 and Zn 511. The highest means of Pb and Hg were measured in (mg/kg): warty venus 0.74; scallops 0.12. The estimated daily intakes for oysters shown it as a good source of Cu and Zn. The higher contribution of Cd and As levels to the provisional tolerable weekly intake in shellfishes suggest a careful approach for consumption.

Rubber mats have not yet been widely established in pig production. However, studies mostly focusing on lesions, lameness and behaviours of lactating and group-housed pregnant sows have reported favourable results. To the best of our knowledge, lesions and lameness in sows or gilts housed individually in rubber floor gestation stalls have not been previously investigated. This study was carried out on a commercial pigbreeding farm service unit during a 28-day production cycle in all seasons. Twentyeight gilts were divided into two equal groups, control and experimental groups, and observed for each cycle. The control group was housed in standard gestation stalls with concrete slatted floor, which in the experimental group was covered with an adjusted rubber mat. During each cycle, lesions were scored on days 1, 8, 15 and 28, and lameness on day 1 and upon gilt transfer from the service unit on day 29. Gilts in rubber floor stalls showed significant reduction (P&lt;0.05) in lesions during the cooler period. Conversely, mats had no impact on lameness score in any season. No significant correlations were found between lesions and the percentage of gilts with a particular lameness score. Accordingly, rubber flooring may improve the welfare of gilts in gestation stalls through lower lesion incidence; however, ambient temperature should be taken into consideration when available.