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11.
A spatial analysis was carried out in order to analyse the reason why the risk of Bovine Spongiform Encephalopathy (BSE) was spatially heterogeneous in France, during the period following the feed ban of Meat and Bone Meal to cattle. The hypothesis of cross-contamination between cattle feedstuff and monogastric feedstuff, which was strongly suggested from previous investigations, was assessed, with the assumption that the higher the pig or poultry density is in a given area, the higher the risk of cross-contamination and cattle infection might be. The data concerned the 467 BSE cases born in France after the ban of meat and bone meal (July 1990) and detected between July 1st, 2001 and December 31, 2003, when the surveillance system was optimal and not spatially biased. The disease mapping models were elaborated with the Bayesian graphical modelling methods and based on a Poisson distribution with spatial smoothing (hierarchical approach) and covariates. The parameters were estimated by a Markov Chain Monte Carlo simulation method. The main result was that the poultry density did not significantly influence the risk of BSE whereas the pig density was significantly associated with an increase in the risk of 2.4% per 10 000 pigs. The areas with a significant pig effect were located in regions with a high pig density as well as a high ratio of pigs to cattle. Despite the absence of a global effect of poultry density on the BSE risk, some areas had a significant poultry effect and the risk was better explained in some others when considering both pig and poultry densities. These findings were in agreement with the hypothesis of cross-contamination, which could take place at the feedstuff factory, during the shipment of food or on the farm. Further studies are needed to more precisely explore how the cross-contamination happened.  相似文献   
12.

The effects of manure handling system and feeding of dairy cows were studied using a simple method to analyse the level of ammonia release in cow stables. Two ratios based on the balances of ammonia and sensible heat, and ammonia and carbon dioxide, respectively, in animal houses were determined and considered to give characteristic levels of the release of ammonia in relation to the animal density independently of the ventilation rate. This required measurements of ammonia, carbon dioxide and temperature with hand-held instruments in the buildings and in outside air. In total, 34 dairy herds were investigated in the south of Sweden. The results clearly demonstrated higher release of ammonia from free stall barn with liquid manure than from conventional tie stall barn with solid manure. There was a clear effect of the content of crude protein, gram per kg dry matter, in the total feed ration on ammonia release in tie stall barn with liquid manure.  相似文献   
13.
Commercial hunting of Spanish wild ungulates has made them an important economic resource. Wild ungulates may have an important role in the maintenance of ixodid tick populations, and also as reservoirs of pathogens. We studied the ixodid ticks that parasitize Iberian red deer and European wild boar from Spain. Ixodid ticks (n=6,336) were collected from 431 Iberian red deer and 142 wild boar in different regions of Spain. We found 10 different ixodid tick species parasitizing Iberian red deer, mainly Hyalomma marginatum marginatum (63.7%), Rhipicephalus (Boophilus) annulatus (7.9%) and R. bursa (7.5%). R. (Boophilus) annulatus was only collected in the province of Cádiz (southern Spain). We found 8 ixodid tick species on the wild boar, mainly Hy. m. marginatum (68.7%), R. bursa (14.6%) and Dermacentor marginatus (9.3%). We found one adult Hy. marginatum rufipes and one adult Hy. anatolicum excavatum parasitizing wild boar from south-central Spain. Mean prevalence of ixodid ticks was 41.3+/-0.08% (n=475) and 31+/-0.09% (n=284) and intensity of parasitization was 13.9+/-0.2 (n=283) and 13.6+/-0.3 (n=130) ticks/animal for Iberian red deer and wild boar, respectively. Only 5 of the 13 ixodid tick species found were shared by Iberian red deer and wild boar. This finding could indicate a host preference when Iberian red deer and wild boar share common habitats. In both Iberian red deer and wild boar from south-central Spain the monthly relative frequencies of Hy. m. marginatum and R. bursa presented an inverse pattern. The highest Hy. m. marginatum relative frequencies coincided with the lowest R. bursa relative frequencies along the year. R. bursa and I. ricinus were present in areas from northern to southern Spain while Hyalomma sp. and D. marginatus were exclusively collected in the two southern thirds of Spain. Haemaphysalis sp. and D. reticulatus were collected in northern Spain. Hy. m. marginatum and R. bursa were present during the whole year in red deer and wild boar from south-central Spain, showing more than one life cycle per year. These results are important for understanding the role of wild ungulates in the maintenance of tick infestations and to improve tick control programmes.  相似文献   
14.
Two isolates of Beauveria bassiana and one of Purpureocillium lilacinum (=Paecilomyces lilacinus) were found infecting Amblyomma cajennense engorged females collected on horses (0.15% infection rate from a total of 1982 specimens) and another two isolates of P. lilacinum and one Metarhizium anisopliae detected in soils (2.1% from 144 samples) collected in typical pasture habitats of this tick in Central Brazil from October 2009 to March 2011. Fungi were isolated from soils with Rhipicephalus sanguineus as surrogate baits. No fungi were found in ticks or soils during the driest months (May to August). Testing pathogenicity of fungi all R. sanguineus females were killed regardless of the isolate and fungi sporulated abundantly on the cadavers. A. cajennense was less susceptible to infection with P. lilacinum within 20 days than R. sanguineus. All three fungal species probably act as natural antagonists of A. cajennense particularly in the rainy season and have interest for integrate control of vectors of Rocky Mountain spotted fever.  相似文献   
15.
The nematode genus Baylisascaris (order Ascaridida, superfamily Ascaridoidea) contains nine relatively host-specific, parasite species of carnivores, omnivores, herbivores, carnivorous marsupials or rodents. They have a facultative heteroxenous life cycle, at least under experimental conditions. Eggs passed in faeces embryonate in the environment and the second-stage larva infective for both definitive and intermediate hosts develops. In intermediate hosts larvae migrate extensively through tissues, where they grow and moult to the third-stage, causing extensive damage. All Baylisascaris spp. are considered a potential cause of visceral, ocular and/or neural larval migrans in mammals including humans and in birds. This paper summarises our current knowledge on the prevalence, biology, pathogenicity and zoonotic significance of three Baylisascaris species: B. transfuga, B. schroederi and B. procyonis which have as definitive hosts bears, giant pandas and raccoons (occasionally dogs), respectively.  相似文献   
16.
The metabolic profile of calf rumen epithelial tissue was for the first time characterized by 1H NMR spectroscopy of chloroform/methanol extracts. The metabolite profiles comprised a number of amino acids, creatine, taurine, short-chain fatty acids and triglycerides. The effects of two dietary interventions; i) four levels of milk allowance with a concomitant different uptake of starter concentrate, and ii) two diets with varying content of starch and fibre in the concentrate, were elucidated. Partial least square regression analysis revealed that the intensity of NMR signals assigned to leucine, isoleucine and valine (0.90  ppm), propionate (1.06 and 2.18  ppm), lactate (1.32  ppm), butyrate (1.56  ppm), acetate (1.93  ppm), glutamine/glutamate (2.18, 2.35 and 3.75  ppm), creatine (3.04 and 3.94  ppm) and glycine (3.55  ppm) decreased with increasing milk allowance. In addition, the analysis revealed that the main difference between the two diets was the content of propionate in the epithelia tissue extracts. Previous morphological analyses of the same rumen epithelia were not able to detect any significant effects of either milk allowance or dietary starch content. Accordingly, the present study demonstrated that 1H NMR spectroscopy applied on extracts is a useful tool for metabolite profiling of epithelial tissue and for following the development of epithelia tissue in young calves, and that the technique may be more sensitive to dietary effects than morphological studies.  相似文献   
17.
The sensitivity and specificity of recombinant open reading frame 5 products used in the Western blotting assay for confirmation of porcine reproductive and respiratory syndrome virus (PRRSV) serologic status were evaluated. The recombinant antigen-based assays were specifically compared with a commercial enzyme-linked immunosorbent assay (ELISA) for PRRSV antibodies using 1) PRRSV antibody-negative reference sera (n = 30), 2) naturally infected pig sera (n = 40), 3) sequential sera obtained from 24 experimentally infected pigs, and 4) sera submitted to 3 state diagnostic laboratories (n = 200). The recombinant antigen assay yielded an average increased sensitivity of 10% over the commercial PRRSV ELISA. The negative controls (group 1 sera) showed no difference between the 2 assays. This comparison confirmed that the recombinant antigen-specific assay was more sensitive than the commercial ELISA and is well suited for routine confirmation of the presence of PRRSV antibodies.  相似文献   
18.
A first record of Taenia ovis krabbei muscle cysts in a muskoxen (Ovibos moschatus) from the Kangerlussuaq population in West Greenland suggests that introduced muskoxen now contributes to the transmission of this parasite in addition to previous observations from caribou (Rangifer tarandus). Muskoxen and caribou are the only wild ungulates in Greenland.  相似文献   
19.
Zoonotic diseases are endemic in the country of Georgia. Using the non‐linear canonical correlation (NCC) method, the aim of this study was to examine the relationship between thirteen epidemiological risk factors and seropositivity to five zoonotic infections (anthrax, Q fever, tularemia, leptospirosis, and Crimean‐Congo hemorrhagic fever [CCHF]) among Georgian military recruits during 2014–2016. According to this multivariate statistical technique, which is suitable for the analysis of two or more sets of qualitative variables simultaneously, two canonical variables were identified. These variables accounted for 68% of the variation between the two sets of categorical variables (“risk factors” and “zoonotic infections”). For the first canonical variable, there was a relationship among CCHF (canonical loading, which is interpreted in the same way as the Pearson's correlation coefficient, [cl] = 0.715), tick bites (cl = 0.418) and slaughter of animals (cl = 0.351). As for the second canonical variable, Q fever (cl = ?0.604) and leptospirosis (cl = ?0.486) were related to rodents inside and outside home (cl = ?0.346) and sweeping in or around home (cl = ?0.317). The NCC method allows researchers to obtain additional insights into the complex relationship between epidemiological risk factors and multiple zoonotic infections.  相似文献   
20.
OBJECTIVE: To determine risk factors associated with identification of an umbilical hernia during the first 2 months after birth in Holstein heifers. DESIGN: Case-control study. ANIMALS: 322 Holstein heifers born in a single herd (45 with an umbilical hernia and 277 without). PROCEDURE: Risk factors that were examined included sire, whether the dam had a history of umbilical hernia, milk yield, duration of gestation, whether the dam had a history of dystocia, whether the heifer had a twin, birth weight, total serum protein concentration, and whether the heifer had an umbilical infection. Logistic regression was used to analyze risk factors. RESULTS: Heifers born to sires with > or = 3 progeny with an umbilical hernia were 2.31 times as likely to develop an umbilical hernia as were heifers born to sires with < or = 2 progeny with an umbilical hernia. Heifers with umbilical infection were 5.65 times as likely to develop an umbilical hernia as were heifers without umbilical infection. CONCLUSIONS AND CLINICAL RELEVANCE: Sire and umbilical infection were associated with risk of an umbilical hernia during the first 2 months of life in Holstein heifers. Attributable proportion analysis indicated that the frequency of umbilical hernias in Holstein heifers with umbilical infection would have been reduced by 82% if umbilical infection had been prevented.  相似文献   
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