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591.
Sylvatic rabies has been present in Croatia for more than three decades, with the red fox (Vulpes vulpes) as the main reservoir. The present epidemic of sylvatic rabies in Croatia started already in 1977 and in the past ten years the disease has become enzootic in the entire country and thus represents a considerable veterinary and public health threat. A genetic characterization and phylogenetic analysis of rabies virus isolates (RABV) from Croatia was performed using panel of 32 selected rabies-positive brain samples from domestic and wild animals collected between 2008 and 2010. Based on the comparison of 367-nucleotide sequences of a conserved region of the nucleoprotein (N) gene (nucleotides 75-441), the phylogenetic analysis revealed a low genetic diversity of currently circulating RABV strains in Croatia. 18 RABV isolates mainly originating from Eastern Croatia clustered with the formerly established Eastern European (EE) lineage, and the rest (14) were identical with the West European (WE) group. Both phylogenetic groups seem to coincide in central regions on both sides along the Save River. A high sequence identity in the N gene of the RABV isolates from neighbouring countries was found.  相似文献   
592.
Anatomical variations can be frequently found in the lymphatic system, which is also true for the shape and course of the thoracic duct (ductus thoracicus), the biggest lymph vessel in the body. From 2012 to 2019, the thoracic duct was successfully dissected in 43 dog carcasses that were used in the anatomy course at the Faculty of Veterinary Medicine, University of Zagreb. The thoracic duct originated from the cranial border of the cisterna chyli as one lymph vessel in 36 dogs (83.7%), as two vessels in six dogs (14%) and as three vessels in one dog (2.3%). We divided the observed thoracic duct variations into six groups according to their anatomical similarities. Considering the specific embryonic development, we can conclude that all observed variations are the result of minor deviations from the standard ontogenesis. However, the importance of thoracic duct variations is significant in surgical procedures done in the thoracic cavity to prevent or cure the chylothorax. Since this research showed variations in 39 out of 43 dogs (90.7%) throughout the whole course of the thoracic duct, great care must be taken while performing the ligation or embolization of the thoracic duct.  相似文献   
593.
The egg shape index and shell deformation of 2466 pullet and 2214 hen eggs have been studied each week over a period of 45 weeks. The weekly and 5‐week averages were utilised for correlation analysis.

A pronounced negative correlation between shape index and shell deformation variations was found for both pullet and hen eggs. The pullet egg correlation coefficient, determined on the basis of the weekly and 5‐week averages, was ‐0.605 and ‐0.885, respectively; while the corresponding values for hen eggs were ‐0.433 and ‐0.510.

It has been pointed out that although a correlated variation of shape index and shell deformation with time might be due to specific conditions, it is reasonable to assume that if the time‐dependent changes of the relevant properties were taken into account in the investigations, an improved correlation might be expected.  相似文献   

594.
The objective of this study was to evaluate effects of two commercially available probiotic additives, containing Bacillus spores, on carcass and meat characteristics, serum lipids and concentration of cecal volatile fatty acids of meat type chickens. Birds were fed regular corn-soy meal based feed (control), supplemented with additive A, containing 1.6 × 10(6) spores per gram of feed of Bacillus subtilis and Bacillus licheniformis (group A) or additive B, containing the same concentration of Bacillus cereus var. toyoi spores (group B). One hundred and twenty birds (20 per replicate) were slaughtered at the age of 55 days. Results showed that birds in group B had higher (p < 0.05) final body weight compared to birds from group A and higher carcass weights and yield percentages compared with control. Breasts and whole legs were also heavier in group B, compared to control, but not the yield. Group A had higher yield of wings and lower abdominal fat weight compared to group B (p< 0.05), but not compared with control. Total cholesterol was not affected by the dietary treatment, on contrary both probiotics elevated the LDL (p < 0.05) and lowered HDL cholesterol, thus unfavourably changed animal's blood serum cholesterol profile. Both probiotics influenced the cecal fermentation, which was observed as decrease in cecal concentrations of propionic, butyric, n-butyric and n-valeric acids, but the differences compared to control group were statistically significant for group A only. It was established that probiotic additive B was more effective regarding carcass and meat part weights than additive A, however the animals from group B also had more abdominal fat and their meat had significantly higher conductivity than control group, which is not considered as beneficial.  相似文献   
595.
We investigated the prevalence of Hepatitis E Virus (HEV), Leptospira and Ascaris suum (A. suum) seropositivity, and of nasal methicillin‐resistant Staphylococcus aureus (MRSA) colonization among Austrian practising veterinarians, and assessed the association with occupational swine livestock exposure. The 261 participants completed a questionnaire on demographics, intensity of occupational swine livestock contact and glove use during handling animals and their secretions. Participants' blood samples were tested for HEV, Leptospira and A. suum seropositivity and nasal swabs cultured for MRSA. We compared swine veterinarians (defined as >3 swine livestock visits/week) to non‐swine veterinarians (≤3 swine livestock visits/week) with regard to the outcomes through calculating prevalence ratio (PR) and 95% confidence interval (CI). Furthermore, the relationship between occupational swine livestock contact and the study outcomes was examined by age (</≥55 years) and glove usage. The prevalence of nasal MRSA colonization was 13.4% (95% CI: 9.3–17.6), of HEV seropositivity 20.8% (95% CI: 15.8–25.7) and A. suum seropositivity 44% (95% CI: 37.7–50.2). The highest anti‐leptospiral antibodies titres were 1:200 (L. hebdomadis) and 1:100 (L. autumnalis, L. caicola) found in three non‐swine veterinarians. Compared to non‐swine veterinarians, swine veterinarians were 1.9 (95% CI: 1.0–3.4) and 1.5 (95%CI: 1.0–2.3) times more likely HEV seropositive and A. suum seropositive, respectively, and 4.8 (95%CI: 2.5; 9.3) times more likely nasally colonized with MRSA. Among glove‐using veterinarians, occupational swine contact was no longer a determinant for HEV seropositivity (PR 1.6; 95% CI: 0.8–2.9). Similar was found for A. suum seropositivity, which was no longer associated with occupational swine livestock contact in the subgroup of glove using, ≥55‐year‐old veterinarians (PR: 1.07; 95% CI: 0.4–3.3). Our findings indicate that >3 occupational swine livestock visits per week is associated with HEV and A. suum seropositivity and nasal MRSA colonization and that glove use may play a putative preventive role in acquiring HEV and A. suum. Further analytical epidemiological studies have to prove the causality of these associations.  相似文献   
596.
The influence of two infectious bursal disease vaccines on the activities of hepatic microsomal enzymes aniline hydroxylase, ethylmorphine N-demethylase, NADPH-cytochrome c reductase, aryl sulphotransferase and p-nitrophenol UDP-glucuronyltransferase was investigated in chickens. The vaccines contained attenuated Winterfield 2512 and VMG-91 strains, respectively. The activities of enzymes were determined on postvaccination days 0, 2, 5 and 7. At the same time, post-mitochondrial supernatant, cytosolic and microsomal pellet protein concentrations were determined. As expected, the antibody titres against infectious bursal disease virus in the serum were increased in both tested groups in relation to each administered vaccine. Using RT-PCR, the presence of the VP2 gene fragment of virus in the liver of chicken was demonstrated 4 and 6 h after vaccination. The results of this study suggest that the two commercial vaccines modulate the activities of five enzymes tested, and that the two attenuated vaccines applied triggered induction and/or inhibition of phases I and II of biotransformation enzyme activities.  相似文献   
597.
598.
Landscape Ecology - Sustainable spatial development requires the establishment of a balance between rational land use and the protection of nature, ecosystems and biodiversity on various spatial...  相似文献   
599.
Streuobst stands, i.e., tall fruit trees on vigorous rootstock on traditional grassland, represent an important source of raw material for the processing industry and for traditional fruit processing on family-run farms. Apart from production aspects, the high-stem orchards also play a role in the conservation of the traditional landscape, and indirectly in maintenance of the viability of rural areas. In this paper, a qualitative multi-attribute model for the assessment of Streuobst stands with respect to their multifunctional characteristics is presented. The assessment is based on four groups of attributes: (1) production criteria (percentage of missing trees), (2) biodiversity (fruit species and varieties, artificial human intervention), (3) landscape diversity (visual appearance, eco-diversity and erosion protection), and (4) function of the stand (row or individual trees, countryside appearance). The assessment is based on the aggregation of input attribute values to an overall assessment through user-defined decision rules. The model was applied to 85 sample stands in NE Slovenia. The assessment shows that most of the stands (48) were rated as ??very poor?? or ??poor??, mainly as a result of poor cultivation and lack of maintenance.  相似文献   
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