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In Bavaria a BHV-1 eradication program was initiated in 1986 and was changed to a compulsory program in 1998. The eradication success increased progressively from < 50% in 1986 to 87% of the farms in 2002. BHV 1-free farms are controlled by bulk milk serology twice a year along with blood serology in animals that are negative but from herds where positive field virus infected animals are present. All serological tests are performed with an indirect ELISA test, all positive results are confirmed by a gB ELISA. Currently about 100.000 virus infected cattle are in Bavarian herds, approximately 80% of these animals are in heavily infected herds (> 10 infected animals). These herds comprise about 5% of all Bavarian herds. The eradication of the virus in these heavily infected herds is the most diifficult, whereas the prevention of new infections appears controllable. In this review current problems in BHV1 eradication are named and possible improvements are discussed.  相似文献   
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Palliwoda  Julia  Banzhaf  Ellen  Priess  Jörg A. 《Landscape Ecology》2020,35(5):1127-1142
Landscape Ecology - The pressure on remaining open spaces of urban green infrastructure (UGI) is high due to increasing urbanization and the multiple requirements of a diverse urban population....  相似文献   
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×Festulolium ssp. are of particular interest as autumn‐saved herbage in the winter grazing system, but information concerning their performance in this low‐input system is not available. To this end, we examined dry matter (DM) yield and forage quality in winter of four different cultivars of ×Festulolium ssp. (×Festulolium pabulare, Festulolium braunii), either with festucoid or loloid attributes, compared with Festuca arundinacea Schreb. Furthermore, pre‐utilization (accumulation since June or July) and date of winter harvest (December or January) were varied examining the influence of different sward management. DM yield, crude protein, metabolizable energy (ME) (in vitro rumen fermentation technique), acid detergent fibre (ADF) and ergosterol concentration were determined. Within all years, the festucoid cultivars (mean 3.4 t ha?1) attained significant higher yields during winter than the loloid cultivars (mean 1.6 t ha?1), but their yields were comparable with F. arundinacea (mean 3.0 t ha?1). Crude protein was decisively influenced by the different yield levels of the cultivars resulting in higher values for the loloid cultivars. Energy concentrations decreased with later winter harvest, whereas ADF as well as ergosterol concentrations frequently increased from December to January. The greatest differences between festucoid and loloid cultivars were generally observed during severe winters. Obviously, the festucoid cultivars were better adapted to a utilization as autumn‐saved herbage than the cultivars with rather loloid attributes. However, the hybrids did not surpass F. arundinacea regarding yield and quality.  相似文献   
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No information is available regarding the mineral content of autumn‐saved herbage during winter grazing under Central European conditions. Therefore, P, K, Na, Mg and Ca concentrations of autumn‐saved growths of Festuca arundinacea and Lolium perenne were analysed considering the potential influence of pre‐utilization (saved from June or July), date of winter harvest (December, January, February) and year (three winters). For all years date of winter harvest was the main source of variance, whereas date of preceding cut had no relevant effect on the mineral concentrations during winter. Already in December P [2.3 to 4.0 g kg?1 dry matter (DM)], Na (0.3 to 3 g kg?1 DM) and Mg (1.0 to 2.4 g kg?1 DM) concentrations were mostly below the required levels for ruminants. The lowest values were detected in February. K levels ranged between 6.6 g kg?1 DM in February and 23.4 g kg?1 DM in December; on average, K concentrations decreased about 10 g kg?1 DM with advancing winter. Ca concentrations (2.9 to 7.4 g kg?1 DM) hardly changed during winter. Related to higher growth rates of F. arundinacea before December, P and Ca concentrations were diluted, but regarding Mg, more wintergreen F. arundinacea reached higher values than L. perenne especially at the beginning of winter.  相似文献   
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A total of 5204 bulk milk samples were tested for antibodies against bovine viral diarrhea virus (BVDV) classified according to the scheme after Alenius. Forty-five percent of the samples from 2002 were classified as class 0 and class 1, 55% as class 2 and 3. 6420 bulk milk samples from 1997 were classified in an independent study in 65.6% class 0 and 1 and 34.4% in class 2 and 3. In class 0 and class 1 farms only very rarely persistent viremic animals have been found, whereas in class 2 and 3 their presence is highly likely. Our studies with non-selected sera defined the serological screening of bulk milk samples as a promising tool for a possible BVDV eradication program in Bavaria.  相似文献   
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