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961.
Slaughterhouse sampling and examination of urogenital tracts of 499 sows and gilts culled for reproductive reasons from 21 Hungarian herds were performed over a 6-year period. The aim was to estimate the prevalence of different urogenital tract lesions, and to provide sensitivity and specificity estimates for macroscopic and bacteriological examinations in the diagnosis of urocystitis and endometritis. Furthermore, the association between endometritis and urocystitis was assessed. The prevalence of main lesions of the urogenital tract was similar to that reported in other studies. The 'sensitivity' of macroscopic and bacteriological methods was determined statistically by taking histopathology as the 'Gold Standard'. As a result, the 'sensitivity' of macroscopic methods for the diagnosis of endometritis and urocystitis was < or = 18.1% and 47.9%, respectively, while the 'sensitivity' of bacteriology for the diagnosis of the same conditions was < or = 31.8% and 63.0%, respectively. The presumed positive association between urocystitis and endometritis was confirmed; it was not confounded by parity. Animals affected by urocystitis had a 3.5 times higher odds to simultaneously have endometritis than animals without urocystitis. 相似文献
962.
Brüssow KP Rátky J Torner H Egerszegi I Schneider F Solti L Tuchscherer A 《Acta veterinaria Hungarica》2002,50(1):101-110
The aim of the present study was to estimate follicular and oocyte development of the same gilts in three phases of their reproductive life--prepuberal gilt (6 months old), cycling gilt (9.5 months old) and primiparous sow. Follicular development was induced by injections of 1000 IU PMSG followed by 500 IU hCG 72 h later. Cumulus-oocyte-complexes (COCs) were recovered from preovulatory follicles of the left ovary, and follicular fluid (FF) from the right ovary always 34 h after hCG by endoscopy. Altogether, 19 gilts were used in the prepuberal (P) and cycling (C) trials and 12 of them in the primiparous trial (S). Altogether 168, 190 and 82 follicles were aspirated from the left ovary and 106, 125 and 42 COCs recovered (recovery rate 60.5 +/- 26.9, 62.7 +/- 20.9 and 52.9 +/- 21.8%). The average number of follicles was higher in C compared to P (19.7 +/- 6.8 vs. 15.7 +/- 6.8, p = 0.06) and to S (14.2 +/- 4.0, p < 0.05), respectively. More uniform expanded COCs were aspirated from prepuberal and cycling gilts as compared to sows (89.7 and 78.4% vs. 46.3%, p < 0.05). Furthermore, the meiotic configuration in oocytes differed (p < 0.05) between these groups (55.5 and 61.7% vs. 0% Telo 1/Meta 2). Concentrations of progesterone in FF decreased (p < 0.05) from 590.0 +/- 333.6 (P) to 249.1 +/- 72.6 (C) and 161.4 +/- 75.2 ng/ml (S). FF concentrations of oestradiol-17 beta were different between gilts and sows (9.3 +/- 2.9, 21.9 +/- 10.6 and 94.0 +/- 15.9 pg/ml, p < 0.05). The progesterone/oestradiol ratio was 72.1, 15.2 and 4.7. Results indicate a different follicular and oocyte development during the investigated lifetime periods. Cycling gilts should preferably be used in IVF and breeding programs. The lower reproductive potential of primiparous sows is taken into consideration at breeding. Prediction of lifetime performance based on individual ovarian reaction of prepuberal gilts is unsuitable. 相似文献
963.
Twenty-four honeybee (Apis mellifera) colonies were used to monitor the efficacy of a solution of 2.9% oxalic acid (OA) and 31.9% sugar against the mite Varroa destructor. Mite mortality was established prior to and after OA treatments, which were conducted in August and September. The treatments resulted in 37% mite mortality as opposed to 1.11% in the controls. OA treatment conducted in September on previously untreated colonies resulted in 25% mite mortality. OA treatments in October and November resulted in approximately 97% mite mortality. These results suggest that OA is effective during the broodless period and less effective when applied to colonies with capped broods. The possible use of OA against the Varroa mite in honeybee colonies as an alternative to routine chemical treatments is discussed. 相似文献
964.
ABSTRACT Production of conidia of Penicillium oxalicum (ATCC number pending), a biocontrol agent of Fusarium oxysporum f. sp. lycopersici, was tested in liquid and solid fermentation. P. oxalicum produced 250-fold more conidia in solid than in liquid fermentation at 30 days after inoculation of substrate. Solid fermentation was carried out in plastic bags (600 cm(3)) especially designed for solid fermentation (VALMIC) containing 50 g of peat/vermiculite (PV) (1:1, wt/wt) with 40% moisture, sealed, sterilized, and then inoculated with 1 ml of a conidial suspension of P. oxalicum (10(5) conidia g(-1) dry substrate), sealed again, and incubated in darkness at 20 to 25 degrees C for 30 days. Addition of amendments to PV in a proportion of 0.5 (wt/wt) significantly increased conidial production of P. oxalicum. The best production was obtained on PV plus meal of cereal grains (barley) or leguminous seeds (lentil) (100-fold higher). Conidial production obtained after 5 days of inoculation was similar to that obtained at 30 days. However, viability of conidia produced in PV plus lentil meal was 35% higher than that of conidia produced in PV plus barley meal. Changes in proportions (1:1:0.5, wt/wt/wt; 1:1:1, wt/wt/wt; 1:0.5:0.5, wt/wt/wt; 1:1:0.5, vol/vol/vol) of components of the substrate (peat/vermiculite/lentil meal) did not enhance production or viability of conidia. Optimal initial moisture in the substrate was 30 to 40%. At lower moistures, significant reductions of production of conidia were observed, particularly at 10%. There was a general decline in the number of conidia in bags with time of storage at -80, -20, 4, and 25 degrees C, or at room temperature (range from 30 to 15 degrees C), with the highest decline occurring from 60 to 180 days. Conidial viability also was reduced with time, except for conidia stored at -20 degrees C. Fresh conidia produced in solid fermentation system or those conidia stored at -20 degrees C for 180 days reduced Fusarium wilt of tomato by 49 and 61%, respectively. 相似文献
965.
Martin G Methner U Rychlik I Barrow PA 《DTW. Deutsche tier?rztliche Wochenschrift》2002,109(4):154-157
A phenomenon of inhibition among Salmonella organisms colonizing the gut of young animals can be demonstrated which is important in connection with immunization using live Salmonella vaccines. For practical utilization of this inhibition phenomenon, research into its specificity is very important. In vitro broth culture and animal experiments have shown inhibition to be genus-specific, i.e. there is no inhibition between strains of different genera of Enterobacteriaceae in most cases. The strongest inhibition occurs between isogenic (identical genotype) strains (strain-specific inhibition). This applies to Salmonella and other genera of Enterobacteriaceae. There was a close correlation between the degree of the inhibitory effect and the genetic relatedness of the strains, as has been demonstrated in Salmonella strains of different epidemiological classification. The inhibitory capacity was most pronounced among closely related strains. Clonal strains of Salmonella Enteritidis phage type 4 fully inhibited caecal colonization by Salmonella Enteritidis phage type 4 strains in 65% of the combinations tested in chicks. In broth culture experiments, the share of combinations with complete inhibition was above 90%. A significant inhibitory competence of a selected strongly inhibitory Salmonella Enteritidis phage type 4 strain against the majority of Salmonella Enteritidis field isolates can be expected. However, Salmonella Enteritidis strains of all phase types showed almost no inhibitory competence against other Salmonella serotypes. 相似文献
966.
Hierarchical Bayesian model for prevalence inferences and determination of a country's status for an animal pathogen 总被引:2,自引:0,他引:2
Certification that a country, region or state is "free" from a pathogen or has a prevalence less than a threshold value has implications for trade in animals and animal products. We develop a Bayesian model for assessment of (i) the probability that a country is "free" of or has an animal pathogen, (ii) the proportion of infected herds in an infected country, and (iii) the within-herd prevalence in infected herds. The model uses test results from animals sampled in a two-stage cluster sample of herds within a country. Model parameters are estimated using modern Markov-chain Monte Carlo methods. We demonstrate our approach using published data from surveys of Newcastle disease and porcine reproductive and respiratory syndrome in Switzerland, and for three simulated data sets. 相似文献
967.
968.
Roussel AJ Hooper RN Cohen ND Bye AD Hicks RJ Bohl TW 《American journal of veterinary research》2000,61(4):420-424
OBJECTIVE: To evaluate the effect of erythromycin on motility of the ileum, cecum, and pelvic flexure of horses during the postoperative and post-recovery periods. ANIMALS: 8 healthy adult horses. PROCEDURE: Horses were anesthetized and bipolar electrodes were implanted in smooth muscle of the ileum, cecum, and pelvic flexure. Approximately 4, 16, and 24 hours (postoperative recording sessions) and at least 8 days (post-recovery recording session) after surgery, myoelectric activity was recorded before and after administration of erythromycin (0.5 mg/kg). RESULTS: Following erythromycin administration, myoelectric activity was increased in the ileum during all postoperative recording sessions but not during the post-recovery recording session. Myoelectric activity was increased in the cecum following erythromycin administration only during the post-recovery recording session. Myoelectric activity was increased in the pelvic flexure following erythromycin administration during all recording sessions. During several recording sessions, there were short periods during which myoelectric activity was significantly decreased following erythromycin administration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that erythromycin has an effect on myoelectric activity of the ileum, cecum, and pelvic flexure in horses; however, prokinetic effects of erythromycin administered during the postoperative period were not always the same as effects obtained when the drug was administered after horses had recovered from the effects of surgical implantation of recording devices. Therefore, caution must be exercised when extrapolating results of prokinetic studies in healthy animals to animals with abnormal gastrointestinal tract motility. 相似文献
969.
Roussel AJ Cohen ND Hooper RN 《Journal of the American Veterinary Medical Association》2000,216(5):730-733
OBJECTIVE: To assess signalment, history, results of clinical and laboratory testing, and outcome for beef cattle with a left displaced abomasum (LDA), right displaced abomasum (RDA), or abomasal volvulus (AV). DESIGN: Retrospective study. ANIMALS: 19 beef cattle with an AV, LDA, or RDA. PROCEDURE: Signalment; history; results of physical examination, diagnostic testing, and surgical exploration; and condition of the animal at discharge were obtained from medical records. RESULTS: Fourteen cattle had an AV, 4 had an RDA, and 1 had an LDA. Duration of clinical signs ranged from 1 to 21 days. Eighteen cattle had an AV or RDA; 7 were Brahmans, 12 were males, and median age was 10 months. Abdominal distention was observed in 11 cattle, heart rate of > or = 100 beats/minute was detected in 14, and the abomasum was palpable per rectum in all cattle in which per rectal examination was performed. Leukocytosis, neutrophilia, hyperglycemia, azotemia, hypochloremia, and hypokalemia were common laboratory findings. At surgery, 3 cattle with an AV or RDA had a ruptured abomasum. Of the remaining 15 cattle, 12 survived. CONCLUSIONS: Clinical course in beef cattle with an AV or RDA was more protracted than that typically associated with these conditions in dairy cattle, but survival rate in beef cattle that did not have rupture of the abomasum was similar to that of dairy cattle. CLINICAL RELEVANCE: Abomasal displacement should be considered for beef cattle with abdominal distention. Prognostic indicators recommended for use in dairy cattle may not be useful for beef cattle. 相似文献
970.
Cohen ND Berry SM Peloso JG Mundy GD Howard IC 《Journal of the American Veterinary Medical Association》2000,216(8):1273-1278
OBJECTIVE: To determine the association between high-speed exercise and risk of injury while racing among Thoroughbreds in Kentucky. DESIGN: Matched case-control study. ANIMALS: 206 Thoroughbreds that sustained a musculoskeletal injury while racing and 412 Thoroughbreds that were not injured during the same races. PROCEDURE: Data regarding official timed workouts and races and the Beyer's numbers for the 3 races before the race during which injury occurred were extracted from past performance charts and compared between injured horses and control horses. RESULTS: For injured horses, cumulative distance of high-speed exercise during the 1- and 2-month periods prior to the race in which injury occurred was significantly less than that of control horses; for either period, a difference of 10 furlongs was associated with approximately 2-fold greater risk of injury. Beyer's numbers were significantly higher for injured horses than for control horses. These effects remained significant after adjusting for age and results of prerace physical inspection. CONCLUSIONS AND CLINICAL RELEVANCE: In Kentucky, injured horses had significantly less cumulative high-speed exercise than did control horses during the 1- and 2-month periods prior to the race in which injury occurred. These results differ from those observed in California. The association of injury with cumulative high-speed exercise appears to vary among regions in the United States. 相似文献