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EN
The aim of this study was to evaluate the occurrence of antibodies to the bluetongue virus (BTV) in animals imported to Poland in 2008, the calves born to bluetongue positive cows and Polish-origin animals kept together with imported cattle. From January 1 to December 15, 2008, a total of 25,495 samples of sera was tested using the c-ELISA and direct ELISA. Out of the tested sera, 1,511 (5.92 %) were found to be positive for BTV. The majority of seropositive cattle were imported to Poland from Germany (987; 65.3%) and the Netherlands (290; 19.2%). Maternal antibodies were detected in 129 (8.5%) samples of sera taken from calves born to seropositive dams of German and Dutch origin. The high number of seroreagents was the result of bluetongue vaccination implemented in BTV-infected EU member States in 2008. In conclusion, it can be stated that surveillance studies should be continued to monitor the actual bluetongue status of Poland. However, an ELISA for the differentiation of infected and vaccinated animals should be introduced to laboratory practice to determine the number of BTV post-infected seropositive animals in the population of imported animals.
EN
The aim of the study was to determine the usefulness of near-infrared spectroscopy (NIRS) for direct estimation of energy, protein and fillunits as well as organic matter digestibility (OMD) for wet whole-crop sorghum silages according to the French feeding system for ruminants INRA (1988). Fifty-eight whole-crop sorghum silages ensiled alone or with the addition of wheat bran, rapeseed meal, or whole-crop maize were used to create a calibration data set. Wet samples of silage were scanned using a spectrophotometer (570–1850 nm). The spectral data were transformed to the first derivative. For scatter correction, standard normal variate and detrending methods were used. The calibration equations were developed using modified partial least squares regression.The accuracy of each equation was evaluated based on the coefficient of determination of calibration (R2 ), standard error of calibration, and standard error of cross validation (SECV). High R2 (> 0.93) were shown for all parameters except OMD (R2 = 0.83).The highest SECV (0.62) was observed for protein units, but all errors were within acceptable values. The results of the study suggest that NIRS may be used for direct prediction of nutritive value of sorghum silages in INRA system units. Furthermore, these results suggest that the NIRS technique may be successfully used for direct estimation of feed units for ruminants in wet silages.
3
Content available Bluetongue vaccines in Europe
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EN
The article reviews the history, present status and the future of BT vaccines in Europe. So far, an attenuated (modified live viruses, MLV) and inactivated virus vaccines against BT were developed and used in the field. Moreover, the virus-like particles (VLPs) produced from recombinant baculovirus, and live recombinant vaccinia or canarypox virus-vectored vaccines were tested in the laboratory. The main aims of BT vaccination strategy are: to prevent clinical disease, to reduce the spread of the BTV in the environment and to protect movement of susceptible animals between affected and free zones. Actually, all of the most recent European BT vaccination campaigns have used exclusively inactivated vaccines. The use of inactivated vaccines avoid risk associated with the use of live-attenuated vaccines, such as reversion to virulence, reassortment of genes with field strain, teratogenicity and insufficient attenuation leading to clinical disease. The mass vaccinations of all susceptible animals are the most efficient veterinary method to fight against BT and successful control of disease. The vaccination of livestock has had a major role in reducing BTV circulation and even in eradicating the virus from most areas of Europe.
EN
Coccidian oocysts were prevalent in nearly 100% of goats and sheep from various localities in Slovakia. In goats 4 Eimeria species were identified: E. ninakohlyakimovae (in kids 40%, in adult goats 51 %), E. arloingi (in kids 43%, in adult goats 20%), E. alijevi (in kids 12%, in adult goats 21 %) and E. hirci (in kids 3%, in adult goats 2%). In addition, 2-6% of coccidian oocysts were not speciated. The mean number of oocysts per gram of faeces (OPG) was 5853 ± 12666 (min. 160-max. 31920) in kids and 2365 ± 4916 (min. 80 - max. 7920) in adult goats. In sheep 5 Eimeria species were identified: E. parva (in lambs 42%, in adult sheep 37%), E. ovinoidalis (in lambs 33%, in adult sheep 29%), E. crandallis (in lambs 14%, in adult sheep 19%), E. bakuensis (in lambs 6%, in adult sheep 6%), E. faurei (in lambs 3%, in adult sheep 4%); 2-5% of coccidian oocysts could not be classified. The mean OPG value was 11941 ±9048 (min. 2680-max. 48880) in lambs and 5250 ± 3412 (min. 880-max. 12280) in adult sheep. In connection with the occurrence of pathogenic Eimeria species, the total counts of selected enterobacteriae in faeces of both goats and sheep were also evaluated. In spite of the fact that in kids the mean OPG numbers were lower, the values of total bacterial counts in their faeces were 1-2 orders of magnitude higher than in lambs. In comparison with lambs, organisms of kids are probably more susceptible to influence of pathogenic Eimeria species. The total counts of selected enterobacteria genera in goats and sheep with coccidiosis were higher than in control groups. These increased bacterial counts might be affected by impaired immunity of the host. Other factors as feeding, breeding conditions and management etc. may be also taken into consideration.
EN
A combination of a flotation/sedimentation experiment and sieve analysis for the reticulorumen (RR) contents of roe deer Capreolus capreolus Linnaeus, 1758, a browsing ruminant, showed that there was no correlation between particle size and particle density. Large particles were present in both the sedimented and the buoyant fraction, which is in accord with the reported absence of stratification of RR contents in browsing ruminants. Comparative sieve analysis of roe deer RR and caecal/rectal material demonstrated that there must be some selective particle retention in the browsing ruminant as well, as a certain fraction of large particles in RR contents does not occur in the caecal/rectal material. These results lead to the explanatory dilemma that, while selective particle retention is observed, it cannot be due to the mechanisms known to work in grazing ruminants.
EN
Over the last three decades, a variety of approaches have been investigated to develop new types of bluetongue virus (BTB) vaccines, ranging from baculovirus-expressed subunit vaccines to live vector vaccines. DNA vaccines against BTV consist of DNA plasmid expressing different BTV proteins after inoculation of the animals. The recombinant viral vector vaccines against BTV are based on recombinant viruses that express desired BTV antigens in the host upon inoculation. Viruses such as vaccinia, modified vaccinia Ancara (MVA), capripox, canarypox, herpes, myxoma and fowlpox viruses have been used as vectors of BTV genes. The reverse genetics (RG) systems for BTV are useful tools for BTV vaccine development. Disabled infectious single-cycle (DISC) vaccines make it possible to restore virus replication and can be used for differentiating infected from vaccinated animals (DIVA). These vaccines are based on the production of a modified virus with a deletion in one or more genes that are essential for virus replication. Another approach for BTV vaccine development using RG is the disabled infectious single-animal (DISA) vaccine, generated by deletion of NS3/NS3a expression. DISC and DISA vaccines can mimic the natural tropism of the virus and can express BTV proteins at the site of infection. Important advantages of these new generation vaccines over the conventional BTV vaccines are their high efficacy as well as the possibility of applying them for DIVA. At present, there are a number of novel laboratoryscale BTV vaccines that could meet vaccine profiles required for different field situations. However, further development and licensing of these vaccine candidates for many BTV serotypes is needed in order to prepare for future BT outbreaks. To date, all novel BTV vaccines described in this paper are still under laboratory testing. They are not available commercially, and the time of their application in the field is still indefinite.
EN
Methane emissions from ruminant livestock are considered to be one of the more potent forms of greenhouse gases contributing to global warming. Many strategies to reduce emissions are targeting the methanogens that inhabit the rumen, but such an approach can only be successful if it targets all the major groups of ruminant methanogens. Therefore, basic knowledge of the diversity of these microbes in breeds of buffalo is required. Therefore, the methanogenic community in the rumen of Surti buffaloes was analyzed by PCR amplification, cloning, and sequencing of methyl coenzyme M reductase (mcrA) gene. A total of 76 clones were identified, revealing 14 different sequences (phylotypes). All 14 sequences were similar to methanogens belonging to the order Methanobacteriales. Within Methanobacteriales, 12 clones (6 OTUs) were similar to Methanosphaera stadtmanae and the remaining 8 phylotypes (64 clones) were similar to unclassified Methanobacteriales. Overall, members of the Methanobacteriales dominated the mcrA clone library in the rumen of Surti buffalo. Further studies and effective strategies can be made to inhibit the growth of Methanobacteriales to reduce methane emission from the rumen which would help in preventing global warming.
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