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51.
An eight-month-old female rottweiler was presented with a history of intermittent lameness of the right hindlimb of 4 weeks duration. Radiographs showed a fragmentation in two plantar sesamoid bones of the metatarsophalangeal joint. Based on these clinical and radiographic signs sesamoid disease of the 2nd and 7th sesamoid bone in the right hindpaw was diagnosed. The fragmented sesamoids were surgically removed and histologically examined. The treatment was successful and the dog became lamnessfree. Additional radiographs showed fragmentations of sesamoid bones VII of both the forepaws, but they did not cause any lameness.  相似文献   
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Clinical studies have shown that Cavalier King Charles Spaniels (CKCS) have a high prevalence of mitral valvular insufficiency (MVI). Echocardiography has the potential to disclose early valvular changes, and the present prospective study was designed to investigate the occurrence of mitral valve prolapse (MVP) in young CKCS without heart murmurs, and to correlate the degree of MVP with the clinical status of the dogs by including CKCS with MVI as well. The study was based on blinded evaluations of echocardiographic recordings of mitral valves from 34 CKCS and 30 control dogs. Thirteen (87%) of 15 three-year-old CKCS without heart murmurs had MVP (2 total and 11 partial), as compared with 1 (7%) of 15 three-year-old normal Beagle dogs (P < 0.0001), and none of 15 three-year-old normal Medium Size Poodles (P < 0.0001). Of 19 CKCS with MVI, MVP was found in 84% of the entire group and in 100% of dogs with pulmonary congestion or edema. The occurrence of total MVP tended to be higher in the group with MVI (47%, 9/19), when compared with the younger CKCS without heart murmurs (13%, 2/15, P = 0.06). MVP was positively associated with excessive heart rate variability (P = 0.003). The radius of curvature of the anterior mitral valve leaflet in systole was significantly reduced in dogs with MVP when compared with those without (P < 0.0001). In conclusion, this study shows that CKCS at an early age have a high occurrence of MVP. This suggests: 1) A genetic predisposition of CKCS to MVP; and 2) That MVP is a pathogenetic factor in the development of mitral valvular insufficiency. Follow up studies may add further support to these proposals, and clarify whether echocardiography may be an aid in selecting CKCS for future breeding.  相似文献   
54.
The cross-reactivity of the purified polysaccharides of Actinobacillus pleuropneumoniae serotypes 1 and 9 were examined using a variety of highly sensitive assays, such as radioimmunoassay, latex agglutination, enzyme-linked immunosorbent assay (ELISA), and immunoblotting. In addition, conventional immunodiffusion was included for comparison. Latex agglutination, utilizing affinity-purified IgG to capsule, was also used to serotype whole cells. Agglutination or precipitation tests (radioimmunoassay, latex agglutination, and immunodiffusion) indicated no cross-reactivity between the capsules of serotypes 1 and 9, and no cross-reactivity between whole cells by latex agglutination. Assays that required binding of the capsule to a solid support (ELISA and immunoblotting) did demonstrate cross-reactions between serotypes 1 and 9 capsules, although reactions with the heterologous serotype were weaker than with the homologous serotype. The cross-reactivity could not be attributed solely to nonspecific factors because similar cross-reactivity did not occur with serotype 5 or 7 capsules by any assay. Reactivity of antisera with homologous or heterologous capsule was reduced, but not completely eliminated, by adsorption with washed, live bacteria of the heterologous serotype. Thus, the assay, as well as the antigen or specificity of the antibody reagent used, may influence the results of A. pleuropneumoniae serotyping or serological tests.  相似文献   
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Experimental lifetime performance data obtained from 156 straightbred Hereford, Angus, and Shorthorn and 172 first-cross heifers were used to estimate heterosis for economic efficiency in a 100-cow herd at age equilibrium under three culling policies and at terminal ages from 6 to 12 yr. All nonpregnant heifers and cows greater than 9 yr of age were culled. The culling policy for removal of nonpregnant cows from second parity through 9 yr of age were 1) no culling, 2) after two consecutive years (actual), and 3) all (imposed). Efficiency was calculated as input cost per unit of output value. A 10-yr average was used for costs of replacement heifers, cow units, and the ratio of calf:cull cow prices (PR), plus higher and lower PR. Input included costs for both cow units and purchased replacements. Output value included both weaned calves and cull cows. Optimum terminal age was mainly a function of PR: 9 yr for average and high PR, but 6 through 9 yr when PR was low, regardless of culling policy or breed groups. Efficiency differences among culling policies were small for high or average PR, but more culling for infertility was beneficial when PR was low. Estimated reductions in unit costs of output value under any culling policy or terminal age were approximately 6% from crossbred cows plus another 6% from crossbred calves, or a total of 12% from specific three-breed crossing of these British breeds. Cost reductions would be somewhat less for rotation crossbreeding but greater for mating smaller crossbred cows with sires of superior growth-carcass breeds.  相似文献   
57.
In two trials, Theileria parva bovis (which causes ‘January disease’ of cattle in Zimbabwe) produced a carrier state, over the 7–12 months after infection. Very severe clinical reactions were caused by infections from small numbers (29–43) of adult Rhipicephalus appendiculatus ticks, which had engorged on immunized cattle in the field. The transmission from healthy recovered cattle housed indoors was less efficient, even with high numbers of ticks (300). Two out of seven attempts were successful and disease reactions were rather severe. A non-pathogenic Theileria assumed to be Theileria taurotragi was transmitted in three out of seven attempts.  相似文献   
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Until recently, Angiostrongylus vasorum was not considered to be an endogenous Danish parasite, since demonstration of this worm had been confined to necropsy findings in 2 dogs, both of which had visited France. During the last 2 years, however, clinical cases have been diagnosed among a considerable number of Danish dogs, none of which had ever been outside Denmark. All these cases have occurred north of Copenhagen, where an endemic focus seems to exist. In this field survey A. vasorum was found for the first time in wild Danish red foxes. Furthermore, experimental infections showed that the parasite can be transferred between foxes and dogs. Consequently, the wild fox population must be considered a potential reservoir for transfer of A. vasorum to domestic dogs.  相似文献   
60.
A chondroma rodens involving the superficial medial aspect of the right orbit was diagnosed in a 9-year-old dog referred because of chronic unilateral epiphora. Examination revealed several ophthalmic abnormalities attributable to a space-occupying mass in the superficial medial aspect of the orbit. The mass was excised; however, regrowths at the primary site necessitated additional surgical interventions. The dog was given radiation therapy, which provided encouraging results. Subtle histologic differences as well as differing epidemiologic features suggest that chondroma rodens is not analogous to the human entity of juvenile aponeurotic fibroma, to which it has been compared in the past.  相似文献   
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