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951.
A dog microfilariae prevalence and risk factor survey was conducted in 51 contiguous municipalities of the Mt. Vesuvius area (Campania region, southern Italy) in order to add data to the limited epidemiological information available regarding filarial worms in this zone. Between May 1999 and June 2000, blood samples were collected from 351 asymptomatic dogs. Blood samples were examined using a modified Knott's technique and histochemical staining in order to count and identify microfilariae. The results were subjected to statistical analysis and choroplethic municipal maps (MMs) were drawn by a geographical information system (GIS) software. Microfilariae were detected in 63 of the 351 dogs surveyed, constituting a total filarial prevalence of 17.9%. In particular, 56 dogs (15.9%) showed only microfilariae of Dipetalonema reconditum; three dogs (0.8%) only microfilariae of Dirofilaria repens; two dogs (0.6%) microfilariae of both D. reconditum and D. repens and two dogs (0.6%) microfilariae of both Dirofilaria immitis and D. repens. High D. reconditum prevalence was associated with hunting practice, masculine gender and older dogs. There was also a tendency to find high prevalence in dogs sampled in the afternoon.In conclusion, the presence of microfilariae of D. reconditum in 92% of microfilaraemic dogs indicates that this filarial worm was the predominant filarial species in dogs in the Mt. Vesuvius area.In addition, the general trends of the MMs showed that D. immitis and D. repens were present only in a few municipalities, whereas D. reconditum was widely and homogeneously spread throughout the entire study area. 相似文献
952.
Jonathan H. Foreman D.V.M. Stephen M. Reed D.V.M. Norman W. Rantanen D.V.M. M.S. Richard M. DeBowes D.V.M. M.S. Pamela C. Wagner D.V.M. M.S. 《Journal of Equine Veterinary Science》1983,3(5):154-164
Since the normal absorption of CSF occurs in the cerebral veins and venous sinuses, any obstruction to the normal flow and absorption of CSF will result in accumulation of CSF central to the site of obstruction. Such accumulation within the cranium is defined as hydrocephalus.A foal was presented with an enlarged and an abnormally-shaped skull, but with normal behavior. The filly's condition deteriorated. Radiographs showed a domeshaped cranial vault with compression of the frontal sinus region. Massive hydrocephalus with little normal cerebral tissue left was diagnosed with ultrasound.Surgery was attempted to relieve the pressure. Eventually the foal was euthanized. Post-mortem confirmed the radiographic and ultrasound diagnosis. Since there was a lack of demonstrable obstruction, the authors suspected the foal had suffered from the Arnold-Chiari syndrome. 相似文献
953.
E M SPICER S J DRIESEN V A FAHY B J HORTON L D SIMS R T JONES R S CUTLER R W PRIME 《Australian veterinary journal》1986,63(3):71-75
Causes of preweaning mortality were examined on a large intensive piggery. Diagnosis was made using comprehensive clinical histories combined with post-mortem data. Two thousand four hundred and twenty-six piglets were born in 238 litters. Pre-parturient and parturient losses were 2.9% and 5.4% of the total numbers of piglets born. Birth to weaning mortality was 11.3%. Among piglets born alive, overlaying was the most frequent cause of death (2.1%), followed by deaths due to diarrhoea (1.7%), anaemia (1.2%), savaging (1.1%) and losses of small weak piglets (0.9%). Most deaths, including stillbirths, were associated with below average birth weight, and two-thirds of all deaths of liveborn pigs occurred within 4 days of birth. Increased litter size resulted in decreased birth weights, an increased percentage of stillborn piglets and mummified foetuses, but duration of parturition was not affected. Stillborn piglets were born late in the litter and after a longer interval between pigs born (interpig interval). Over 70% of deaths due to overlay were in previously healthy piglets, but some were associated with illness of the sow (18%) or both sow and piglet (3%). Savaging was confined mainly to first parity sows and was responsible for 20% of all deaths in these litters. Sixty-two per cent of all piglets with a birth weight of less than 800g were stillborn or died before weaning compared with 18.7% mortality for all piglets. Anaemia in piglets was considered to be due to umbilical haemorrhage. Anaemic piglets had a 36% mortality to weaning compared with 10% for non-anaemic piglets.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
954.
955.
M C Healey H M Gharpure S J Kleinschuster H H Hwang A V Johnston 《American journal of veterinary research》1986,47(7):1446-1451
Three monoclonal antibodies (LG17, LG30, and LG33) were used to identify outer membrane antigens of Actinobacillus sp (As8C isolate) cultured from the epididymides of an infected ram lamb. Specificity of the 3 antibodies to As8C antigens was determined by use of bacterial agglutination, the enzyme-linked immunosorbent assay, and the indirect fluorescent antibody test. Results of immunoelectron microscopy confirmed that each antibody was specific for epitopes on As8C outer membrane antigens. Evaluation by use of enzyme-linked immunoelectrotransfer blot indicated that target antigens for LG17 and LG33 antibodies had molecular weights of 10 kilodaltons and 43 kilodaltons, respectively. Multiple-band staining was observed with the LG33 antibody. The target antigen for the LG30 antibody could not be discerned by use of enzyme-linked immunoelectrotransfer blot. For each of the 3 monoclonal antibodies, enzyme-linked immunosorbent assay titers were obtained for Actinobacillus seminis, A actinomycetemcomitans, and 10 field isolates of Actinobacillus spp. Target antigens for LG17 and LG30 antibodies occurred infrequently or were absent on these bacteria. However, the target antigen for the LG33 antibody was shared by Actinobacillus seminis, A actinomycetemcomitans, and the 10 field isolates of Actinobacillus spp, indicating some diversity of outer membrane antigens between isolates. 相似文献
956.
957.
Yield and quality of fresh ears were measured in field plots of selected hybrids of sweet corn (Zea mays L.) that were affected by rust (Puccinia sorghi Schw.) or were nearly rust-free (mancozeb-sprayed). In 1978, 28 hybrids were tested. Losses in total yield ranged from zero in the more resistant entries to nearly 50% in more susceptible entries. In 1979, three cultivars were planted. Yield losses of these cultivars were similar in ranking order to those in 1978, although the loss was greater in late-planted plots because of the greater final severity of the disease. Losses in total yield in late-planted sweet corn were 18%, 26% and 49% for cv. Sugarloaf (most resistant), cv. Jubilee (intermediate) and cv. Style Pak (most susceptible), respectively. 相似文献
958.
V Antal T Antal I Szabó G Vajda A Polner I Szollár B Totth G Laber L Stipkovits 《Archiv fuer experimentelle veterinaermedizin》1989,43(5):751-754
The authors examined 585 samples from 92 mares of 2 studs and 346 nasal swabs taken from their foals for the presence of mycoplasmas. The positive rates of mares and foals were 81.5% and 71.7%, respectively, with positivity of samples being variable. Clinical symptoms developed in 2-4 waves and lasted 3-7 days, with intervals of 7-12 days. The disease started in April among foals born in February, at an average age of 88 days. Later on, the average age of the affected foals decreased. There was a correlation between presence of mycoplasmas in nasal cavity and disease of foals. 相似文献
959.
In 15 selected stocks in the Strakonice district, 507 slaughter pigs, 708 small terrestric mammals and 110 free-living birds were examined in a two-year period (1986-1987) to study the occurrence of carriers of yersiniae and their elimination. Rectal smears from 243 persons working in livestock production were examined in the same way. Standard bacteriological methods, recent examination procedures (Aulisio et al., 1980; Aldová, 1981) and a diagnostic antiserum (03 IMUNA Sarisské Michalany) were used for the examination. The following results were obtained: In pigs: 1. yersiniae were detected in 65 cases (12.8%); of this, in 31 cases they occurred in the tonsils, in 35 cases in ileum, and twice in the ileocaecal lymph nodes. 2. Epidemiologically significant Y. enterocolitica 4;03 was detected in 28 cases (5.5%); of this, 22 times in the tonsils, 7 times in ileum, and once in the ileocaecal lymph nodes. 3. The seasonal nature of the occurrence of yersiniae was confirmed in 1986, with maxima in winter-spring, but in 1987 their occurrence declined substantially to less than a quarter. In the small mammals, yersiniae were detected 28 times (4%); of this, 7 times in common field mouse, 11 times in common vole, 5 times in house mouse, twice in shrew, once in Apodemus flavicollis, and once in Apodemus sp. 2. Y. enterocolitica 4;03 was detected twice (0.26%), both cases in the house mouse. Other results: 1. In all the 110 free-living birds the examination for yersiniae had a negative result; 2. in the rectal smears of 243 persons employed in livestock production, yersiniae were identified twice (0.8%)--in one case Y. enterocolitica 1, in the other Y. enterocolitica biovars 1 and 2. 相似文献
960.
There were repeated histological bioptic examinations of the endometrium during the period from the second to twentieth day post partum (p.p.) in cows with afterbirth retention (n = 5), with developing puerperal endometritis (n = 5), and with a physiological course of puerperium (n = 5). In cows with a physiological course of puerperium, a finished process of epithelization of endometrium with a morphological and functional consolidation of the epithelium could be observed on the 20th day p.p. In cows with disturbed puerperium, the surface epithelium still exhibited signs of disintegration and a low secretion activity. The endometria of both groups of cows with pathological puerperium had a high degree of infiltration with neutrophil granulocytes: in cows with retained afterbirth this picture was characteristic already the second day p.p. On the other hand, the endometrium of cows with physiological puerperium was characterized by a higher occurrence of folliculoid nodules as early as on the tenth day p.p., and a rapid increase in the number of fat cells and activated histiocytes--macrophages could be observed in the endometrium of these cows between the 15th and 20th day p.p. The dynamics of occurrence of mobile cells in the studied groups of cows confirmed their importance for a physiological course of the restitution of endometrium during the puerperium of cows. 相似文献