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51.
52.
Fish and chips     
Summary

Generalized cowpox infection in the Patagonian cavy may represent a threat to the health of immunocompromised persons. We report the first case of cowpoxvirus infection in the Patagonian cavy in an educational animal park. The mara developed extensive pox lesions, shedding large amounts of viral particles. The ending of vaccination programmes against smallpox in the late 1970's may lead to an increase in susceptibility of humans to zoonotic poxviruses.  相似文献   
53.
Investigations were carried out concerning possible litter differences in locomotory ability and exterior conformation, and possible litter and sire group differences in the occurrence of skeletal lesions and in joint shape. The animals were from a breed experiment involving 6 litters, 8 feeding experiments involving 64 litters, and a selection experiment totalling 70 litters and 25 sire groups distributed in 3 lines. One hundred and twenty-one out of 285 P values for litter or sire group differences were statistically significant (P < 0.05). This shows, with reservations concerning the possibility that different environmental conditions up to 20 kg live weight may have produced a litter effect on pigs from the breed and feeding experiments, that heredity plays a significant part in the leg weakness complex. It seems justified to conclude that it partly is the inheritance of certain joint shapes and exterior conformational features, which influence the degree of joint lesions and locomotory ability and give rise to litter differences. This gives the theoretical possibility of selecting for more lasting joints and better locomotory ability using criteria based on joint shape and exterior conformation.  相似文献   
54.
Catrin Borberg  Steffen Hoy   《Livestock Science》2009,125(2-3):314-317
A total number of 26 groups of 8 sows each were mixed after weaning the piglets in a special stimulation pen, including 13 groups with and 13 groups without boar presence. Behavioural measurements were taken for 48 h after mixing and all agonistic interactions (AI) were recorded into a winner–loser-matrix. Additionally, the duration of the AI and the start situation (aggressor–receiver) were determined. Also the skin lesions of each sow 24 h before and after mixing were scored. A total of 90% of the AI were initiated by the dominant sow in the concerned dyad. In more than 50% of all cases low ranking sows were attacked by higher ranking sows. Low ranking sows had a significantly higher skin lesion score than high ranking sows (9.6 vs 6.9). 12.8% of the AI were fights. Fights (mean duration: 30 s) took ten times longer than attacks. Boar presence did not affect the total number of AI per sow but decreased the number of fights to almost half (3.6 vs 6.4). Duration of fighting was shortened by boar presence (14.9 vs 39.6 s). The skin lesion score and the sociometric parameters were unaffected by treatment. Frequency of AI per group was affected by the microclimate and the number of acquainted dyads (pairs). The number of AI was reduced by a higher enthalpy and a higher number of acquainted sows, respectively.  相似文献   
55.
In this longitudinal observational study, 118 growing Newfoundland dogs were followed with sequential radiographic examination of the right front limb, which were scheduled at ages 3, 4, 6, 12, 18, and 24 months to record evidence of skeletal changes. All affected dogs had evidence of changes at 6 months and dogs included in this study had radiographic examination at 6 months and at least two other scheduled examinations that included either 4 or 12 months. The dogs were privately owned and had individualized nutrition and environment with no maintenance protocol required by the project leaders. Irregularities in bone remodeling in the distal radius and ulna were seen in radiographs of 54 of 118 (45.8%) dogs. These irregularities differ from changes previously described in the Newfoundland dog. The reported irregularities were seen as islands of reduced opacity outlined by thickened, radiopaque osseous trabeculae, which were aligned with the axis of stress. All the 54 dogs with irregularities during some phase of development consistently had changes at 6 months of age. Reorganization of the changes in the bone was slow, and residual changes were visible at 18-24 months of age in many cases. The significance of these findings may lie in their potential for misinterpretation if they had been discovered in the presence of clinical signs such as any lameness or growth arrest. Radiographic appearance indicates disturbances in the bone maturation. The etiopathogenesis is unclear. Nutritional, environmental and genetic factors have to be studied.  相似文献   
56.
氯化镉对小鼠的病理损伤和硒的保护效应   总被引:2,自引:0,他引:2  
采用腹腔注射的方法在90只昆明种小鼠中进行了镉中毒与硒解毒的研究。结果表明,镉中毒组在注射后1~5周内,表现出明显的病理变化,特征为全身小动脉血管及肝、肾、心、肺、脑等器官有严重的病理损伤,且肝脏超微病变明显;而硒解毒组小鼠上述变化明显减轻,以肝、心、脾表现最为明显,结果表明硒可颉颃镉在小鼠的毒性。  相似文献   
57.
Fiftysix calves, in 2 similar experiments, were given 1 of 4 diets including a high lactose milk replacer: ground barley (GB), ground barley plus coarse hay (GB + GH), coarse hay (CH) and the liquid diet only (NS) ; the 2 last diets were held as controls. The calves were on the experimental diet from 1–2 weeks of age until slaughtered at 7-8 weeks of age. As observed by stereo-microscopy, the ruminai papillae in calves fed on GB were thickened, mostly finger- or club-shaped and sometimes nodular; nodular papillae were always arranged on prominent mucosal folds. Scattered nodular papillae had white coats. For calves fed on GB + CH the papillae were mostly finger- or tongue-shaped. Histologically papillae in calves fed on GB had hyperplasia of secondary papillae and epithelial layers. Microabscesses associated with penetrating hairs were frequent, and some calves had dyskeratosis with infiltration of polymorphonuclear leucocytes at the apex of papillae, identified as the white coats. For calves given GB+CH, abscesses and apical dyskeratosis were absent and the hyperplasia of epithelial layers milder than in the case of the GB diet. An ameliorative effect of hay on papillary changes caused by barley is indicated.  相似文献   
58.
The aim of this study was to classify the histopathological features of pigs infected with Mycobacterium avium complex (MAC). We used slaughtered pig organs systemically infected with MAC. The results showed granulomatous lesions which were observed predominantly in the digestive organs and regional lymph nodes rather than respiratory organs. The histological picture showed a wide range of granulomatous stages from exudative to fibrotic reactions to the MAC infection. Eosinophils and giant cells were characteristically observed in the exudative reactions. The histopathological type in primary focus tended to be maintained in the respective organs. Most strains with the same genotype showed pathogenicity for guinea pigs irrespective of the type of granuloma. Although these findings suggest that different stages of a granulomatous lesion originating from the same causative agent might influence histological patterns, other possibilities such as the hereditary background of the host, or the effects of viral infections should be considered.  相似文献   
59.
Sheep pox disease outbreaks were recorded among Madras Red (n=145) and Mechery (n=80) breeds of indigenous sheep on three farms in Tamilnadu. Over both breeds, adult mortality rate ranged from 2.66% to 37.5% and lamb mortality ranged from 10% to 17.33%. However, mortality was more in Mechery sheep (50% overall; 37.5% adults, 12.5% lambs) than in Madras Red sheep (24.28% overall; 10.34% adults, 13.79% lambs). The clinical signs observed were high fever, anorexia, respiratory distress, mucopurulent nasal discharge and in a few cases diarrhoea. Cutaneous lesions were mainly observed around nostrils, eyes, lips, ears and in the abdomen. Most of the lesions were covered with purulent materials and on cleaning with sterile swabs, fresh wounds were observed. Dry scabs were also observed over the oral commissure and maxillary areas, which on removal exposed fresh wounds. Important observations on necropsy were severe nodular lesions in the lungs and intestine. The disease was diagnosed as sheep pox by agar gel immunodiffusion test, isolation of virus and its neutralization in BHK(21) cells by specific antiserum and by electron microscopy.  相似文献   
60.
Atlantic halibut, Hippoglossus hippoglossus (L.), that were cultured in tanks with a smooth bottom (gel‐coated fibreglass) substrate developed papillary hyperplasia and skin erosions on the blind (ventral) side. No viruses, bacteria or parasites were observed in any sections of affected skin. Comparison of microscopic pathology with that of skin from normal, wild‐caught halibut showed severe epidermal proliferation with foci of severe mucous cell hyperplasia. Both epidermal thickness and mucous cell density were significantly greater in fish held on a smooth substrate compared to skin of healthy fish. Spongiosis was present, especially at the base of the papillary, hyperplastic epidermis, and there was a chronic inflammatory infiltrate in the scale pockets composed of lymphocytes, histiocytes and erythrocytes. Skin erosions had various degrees of epidermal loss, in some cases to the basement membrane. A predisposing factor for the epidermal sloughing may have been related to the spongiosis, and the vacuolated, degenerated basal cells. When affected halibut were cultured for an additional 28, 62 or 97 days on a sand substrate, which is conducive to skin lesion healing, there was no apparent change in epidermal thickness over time. However, mucous cell density significantly increased from day 0 to 97 during the healing process.  相似文献   
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