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81.
In the last few years, newly recognized paramyxoviruses have been associated with severe disease in several animal species, including swine, as well as in human beings. Recently, a paramyxovirus was isolated from a swine herd in the northcentral United States that experienced an epizootic of respiratory and central nervous system disease. Affected pigs had interstitial pneumonia with necrotizing bronchiolitis and encephalitis characterized by lymphocytic perivasculitis and diffuse gliosis. Germ-free pigs inoculated with this isolate developed mild clinical illness and similar but less severe histopathologic lesions in lungs and brain.  相似文献   
82.
The inheritance of distichiasis was analyzed in the dog breed Elo using complex segregation analyses.The different hypotheses of monogenic, mixed-monogenic-polygenic and polygenic inheritance as well as a pure environmental model were tested. In further analyses the number of examined Elo dogs per ophthalmologist and the proportion of genes of Eurasian and Old English Sheepdogs were included in the models as covariates. Seven families were randomly collected for the analyses.The seven families comprised a total of 296 animals with 218 examined and 65 affected dogs. A genetic component was verified for the prevalence of distichiasis. Mixed models with a recessive, dominant or arbitrary major gene effect and the polygenic model represented likely hypotheses of inheritance. The prevalence of distichiasis observed was insufficiently explained by non-genetic factors and the breed composition. Therefore, a model only including non-genetic factors and the breed composition could be excluded.  相似文献   
83.
Although inclusion in formal value chains extends the prospect of improving the livelihoods of rural small-scale producers, such a step is often contingent on compliance with internationally-promoted food safety standards. Limited research has addressed the challenges this represents for small rural producers who, grounded in culturally-embedded food safety conceptions, face difficulties in complying. We address this gap here through a multiple case study involving four public school feeding programs that source meals from local rural providers in the Bolivian Altiplan. Institutional logics theory is used to describe public food safety regulations and to compare them to food safety conceptions in the local indigenous Aymara rural setting. We identify a value-based conflict that leads to non-compliance of formal food safety rules that jeopardizes the participation of small farmers in the market. These include: (1) partial adoption of formal rules; (2) selective adoption of convenient rules; and (3) ceremonial adoption to avoid compliance. Decoupling strategies allow local actors to largely disregard the formal food safety regulations while accommodating traditional cultural practices and continuing to access the market. However, these practices put the long-term sustainability of the farmers’ participation in potentially favorable opportunities at risk.  相似文献   
84.
Seven field isolates of German origin and the type strain WVU 1853 of Mycoplasma synoviae (MS) were experimentally investigated for their virulence in mycoplasma-free broiler chickens. Two groups of birds were inoculated at 6 days of age with each isolate, one group into the thoracic air sac and the other group intravenously and all surviving birds were examined at necropsy 17 days post inoculation (pi). Groups of negative control birds received sterile Frey's broth medium by intravenous and intra-air sac inoculation, respectively. Variation in virulence was evaluated on the basis of significant differences in incidence, severity and extend of MS-induced airsacculitis and synovitis as well as isolation rates of MS especially from parenchymous organs. All the strains tested were pathogenic but varied in their virulence for broiler chickens. Based on differences of the virulence, the isolates were classified to the categories: (1.) highly virulent, (2.) virulent, (3.) moderately virulent and (4.) slightly virulent. (1) Strains WVU 1853 and 246-91 induced a systemic disease associated with multiple synovitis and bilateral airsacculitis (2) Strains 93-92 and 151-77 induced bilateral airsacculitis similar to WVU 1853 and 246-91 but rarely a systemic disease after exposure by intra-thoracic airsac inoculation. (3) In comparison, strains 27-79, 76-93 and 513-83 caused less frequently airsacculitis and even if, then only at the side of intra-airsac exposure. (4) Strain 91-93 has been found to differ significantly from all the other isolates in its capacity to produce disease independently from the inoculation route. After intravenous inoculation, findings gave no indications for strains with selective tropism to the epithelial membranes of the lower respiratory tract or to those of the joints, tendon sheaths and bursae. However, the presented data of the experiments suggest that the MS strains tested differ in their potential capacity to invade systemically and produce acute septicaemia.  相似文献   
85.
Genetic parameters were estimated for prevalences of primary cataract (CAT), persistent pupillary membrane (PPM) and distichiasis (DIST) in 615 single-colored and 617 multi-colored English Cocker Spaniels (ECS) bred in the German kennel club for Spaniels (Jagdspaniel-Klub e.V.). CAT or CAT diagnosed in dogs up to three and a half years of age (early-onset cataract, CAT-early) and CAT diagnosed in dogs over three and a half years of age (late-onset cataract, CAT-late), PPM and DIST were included as binary traits in multivariate genetic analyses. Heritabilities on the underlying liability scale were 0.15 for CAT, 0.34 for CAT-early, 0.13 for CAT-late, 0.46 for PPM, and 0.62 for DIST in single-colored ECS and 0.06 for CAT, 0.13 for CAT-early, 0.14 for CAT-late, 0.10 for PPM, and 0.61 for DIST in multi-colored ECS. There were indications for a different genetic basis of CAT-early and CAT-late in single-colored ECS as genetic correlations were close to zero. In multi-colored ECS, a similar tendency for CAT-early and CAT-late could be observed.  相似文献   
86.
Two complementary approaches to produce visual information from reproduction records are described and exemplified. The Event Display shows all reproductive events, over a year, for all cows in a herd, by symbols placed in an array with columns representing calendar weeks and rows representing individual cows. The Reproduction Monitor consists of graphs of insemination and pregnancy rates evaluated weekly with a Bayesian technique. These visual monitoring tools are well suited to explore temporal variation in reproductive performance, they provide a quick overview of herd performance, and they provide information about individual animals.  相似文献   
87.
The aims of this study were to analyze the influence of systematic environmental effects on the prevalence of primary non-congenital cataract (CAT), fibreglass cataract in the nucleus (FCN), and prominent suture lines (PSL) and to estimate the heritabilities of these eye diseases in the wild-boar-colored wirehaired Dachshunds (WWD) bred in the German Dachshund Club 1888 e.V. (DTK). Data included 2,430 WWD born between 1995 and 2003 that were examined between 1996 and 2005 by veterinary ophthalmologists. CAT was diagnosed in 3.83% of the 2,430 dogs, FCN in 3.74%, and PSL in 2.76%. Sex, size, inbreeding coefficient, the age of the dog at examination, experience of the veterinary ophthalmologist and the additive genetic effect of the animal were considered in the multivariate linear model. The age of the dog at examination had a significant influence on the prevalence of FCN. The degree of experience of the veterinary ophthalmologist significantly influenced the prevalence of FCN and PSL. Using a transformation into the Dempster-Lerner threshold model, heritability estimates (h(DL)2) for WWD were h(DL)2 = 0.39 +/- 0.13 for CAT, h(DL)2 = 0.36 +/- 0.11 for FCN and h(DL)2 = 0.49 +/- 0.12 for PSL. Positive genetic correlations (r(g)) were found between CAT and FCN (r(g) = 0.58 +/- 0.21), between PSL and FCN (r(g) = 0.83 +/- 0.23), and between CAT and PSL (r(g) = 0.79 +/- 0.06). The eye diseases investigated here in the Dachshund were found to be genetically influenced and positively correlated traits.  相似文献   
88.
Immunohistochemical detection of lymphatic capillaries was performed in the periodontium of maxillary and mandibular cheek teeth from 6 horses (aged 3-23 years). Tissue sections of the periodontium were taken at 4 different horizontal levels along the long axis of the tooth. The specimens were processed for immunoreaction with anti-Prox1, in order to distinguish lymphatic endothelium from blood vascular endothelium. Lymphatic vessels were detected in all periodontal tissues except for the dental cementum. Lymphatic capillaries were most densely distributed in the gingiva compared to other tissues of the periodontium. Lymphatic capillaries were found most consistently in samples taken from the gingival and subgingival regions in all horses examined. Within these levels, the gingiva as well as the spongiosa of the maxillary and mandibular bone had the greatest incidence of lymphatic vessels. Considering the distinct distribution of the lymphatic capillaries in the periodontium of the maxillary and mandibular cheek teeth, two complementary lymphatic drainage pathways are proposed: (1) superficial lymph drainage via the gingiva, emptying into the mandibular lymph nodes; (2) deep lymph drainage via the mandibular and maxillary spongiosa, emptying into the mandibular and retropharyngeal lymph nodes, respectively.  相似文献   
89.
This study tested for the first time an optoelectronic device (Perometer*) measuring limb volume of horses. An analysis of its application was performed regarding the influence of different types of physical exercise on the volume of the extremities. 40 horses were divided into four groups often horses, each group being exposed to exercise, differing in kind and duration of lunging, horse-ridden and riderless. The volume measurement was performed by determining the inactive value (I) after a twelfe-hour standing period, the load value (II) immediately after exercise and recovery value (III) one hour after exercise. The results showed a highly significant decrease in limb volume of 5.7% between values (I) and (II), as well as a highly significant increase of 68% between (II) and (III). The volume changes observed in male horses were significantly higher than in female horses. Volume changes in horse-ridden groups were higher than riderless ones, but not significant. There were fewer leg volume changes at low ambient temperatures (1-12 degrees C) compared to high temperatures (23-31 degrees C), but these were not statistically significant. Well-trained horses showed lower volume changes than less trained horses (not statistically significant). The Perometer is a fast and reliable tool for measuring limb volume of horses. The ICC (Interclass Correlation Coefficient) calculated a high measurement reproducibility of 0.996. A variance analysis showed no significant differences between the three repeated leg measurements. Thus, the Perometer can be used for monitoring and quantifying edema and documenting limb volume changes resulting from training, wearing compression stockings or bandages, manual lymph drainage.  相似文献   
90.
Attaching and effacing Escherichia coli (AEEC) adhere to mucosal epithelium in both small and large intestine and induce a distinctive lesion characterized by an irregular scalloped appearance of the epithelial layer. Infection with attaching and effacing E. coli was detected in 14 calves, 7 pigs, 2 lambs, and 3 dogs. Affected animals were from farms and kennels in South Dakota, Minnesota, Iowa, Nebraska, and Wisconsin. Ages of affected animals were calves, 2 days to 4 months; pigs, 1-6 weeks; lambs, 1 week; and dogs, 7-8 weeks. Clinical signs included diarrhea in all animals, but other nonenteric disease problems were present in some animals. Concurrent infection with other enteropathogens was detected in 9 calves and 5 pigs. Infection with AEEC appeared to be the sole cause of illness and death in some animals. There was evidence of intestinal hemorrhage in 5 of the calves and in all 3 dogs. Attaching and effacing lesions varied from small scattered foci to widespread involvement of large areas of intestinal mucosa. Verotoxin was produced by E. coli strains isolated from 9 calves, but not by strains from pigs, lambs, or dogs.  相似文献   
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