Pathogenicity of porcine enterotoxigenic Escherichia coli that do not express K88, K99, F41, or 987P adhesins.     

T A Casey  B Nagy  H W Moon 《American journal of veterinary research》1992,53(9):1488-1492

Three-week-old weaned and colostrum-deprived neonatal (less than 1 day old) pigs were inoculated to determine the pathogenicity of 2 enterotoxigenic Escherichia coli isolates that do not express K88, K99, F41, or 987P adhesins (strains 2134 and 2171). Strains 2134 and 2171 were isolated from pigs that had diarrhea after weaning attributable to enterotoxigenic E coli infection. We found that both strains of E coli adhered in the ileum and caused diarrhea in pigs of both age groups. In control experiments, adherent bacteria were not seen in the ileum of pigs less than 1 day old or 3 weeks old that were noninoculated or inoculated with a nonpathogenic strain of E coli. These control pigs did not develop diarrhea. Antisera raised against strains 2134 and 2171 and absorbed with the autologous strain, grown at 18 C, were used for bacterial-agglutination and colony-immunoblot assays. Both absorbed antisera reacted with strains 2134 and 2171, but not with strains that express K99, F41, or 987P adhesins. A cross-reaction was observed with 2 wild-type K88 strains, but not with a K12 strain that expresses K88 pili. Indirect immunofluorescence with these absorbed antisera revealed adherent bacteria in frozen sections of ileum from pigs infected with either strain. We concluded that these strains are pathogenic and express a common surface antigen that may be a novel adhesin in E coli strains that cause diarrhea in weaned pigs.  相似文献   

Estrogen and progesterone receptor status of mammary carcinomas and correlation with clinical outcome in dogs.   总被引：3，自引：0，他引：3  

E A Sartin  S Barnes  R P Kwapien  L G Wolfe 《American journal of veterinary research》1992,53(11):2196-2200

Estrogen and progesterone receptors (ER, PR) were measured in cytosol fractions from 18 primary canine mammary carcinomas by use of biochemical assays. One or both receptors were detected (> 10 fmol/mg of cytosol protein) in 11 tumors: 5 ER and PR; 2 ER only; 4 PR only. Mean cytoplasmic receptor concentrations (fmol/mg of cytosol protein) were 22.8 +/- 2.9 (SEM) for ER and 51.0 +/- 10.3 for PR in tumors containing ER and PR, 28.8 +/- 12.1 for ER in tumors containing only ER and 13.2 +/- 1.5 for PR in tumors containing only PR. Estrogen or progesterone receptors or both were identified in 6 of 9 tubular adenocarcinomas, 4 of 5 papillary adenocarcinomas, and 1 of 1 squamous cell carcinoma. These receptors were not identified in solid carcinomas (n = 2) or a single spindle cell carcinoma. Although the number of cases was limited, survival times of dogs tended to be longest in those with tumors containing ER alone or in combination with PR, intermediate in those with tumors containing only PR, and shortest in those with tumors without ER or PR. A correlation was not apparent between receptor status and age, presence of ovaries, tumor size, or histologic classification of the tumor. In the analysis of this series, the extent of surgery (mastectomy of the involved gland vs unilateral or bilateral mastectomy) did not appear to influence the outcome of the disease, and metastasis to regional lymph nodes did not appear to be a reliable prognostic indicator.  相似文献   

Infection of bovine fetuses at 120 days' gestation with virulent and avirulent strains of bluetongue virus serotype 11.     

A S Waldvogel  G A Anderson  D L Phillips  B I Osburn 《Comparative immunology, microbiology and infectious diseases》1992,15(1):53-63

Bluetongue virus infection in sheep and cattle during fetal development causes neuropathology. Two strains of bluetongue virus serotype 11 designated as UC-2 and UC-8 have different virulence patterns in newborn mice. These viruses have distinctly different electropherotype patterns on polyacrylamide gel electrophoresis indicating a genetic difference in these two viruses of the same serotype. Four bovine fetuses each were inoculated intramuscularly with either UC-2 or UC-8, and one fetus was inoculated with placebo. The inoculation was made intramuscularly through the uterine wall at 120 days' gestation, and the bovine fetuses were recovered by cesarean section 12 or 20 days after inoculation. Fetal blood was collected for virus isolation and serology. Virus was reisolated from brain, blood, lung and liver. Both strains, UC-2 and UC-8, cause severe lesions in the 120 day fetuses. The encephalomalacic lesions occurred earlier and were more severe in fetuses inoculated with UC-8 as compared to those inoculated with UC-2. The subtle differences observed in the fetuses inoculated with the two different strains suggest that there is a difference in pathogenic potential of the two viruses. These differences do not appear to be completely dependent upon the host species.  相似文献   

In vitro nitroimidazole resistance of Trichomonas gallinae and successful therapy with an increased dosage of ronidazole in racing pigeons (Columba livia domestica)     

F. F. J. FRANSSEN  J. T. LUMEIJ DVM PhD  † 《Journal of veterinary pharmacology and therapeutics》1992,15(4):409-415

Six out of eight different Trichomonas gallinae strains isolated from racing pigeons proved to be resistant to the nitroimidazole drugs ronidazole, carnidazole and metronidazole. The minimal cytocidal concentration of ronidazole was determined in in vitro experiments. Moreover, a therapeutic dose for ronidazole was determined for the control of trichomoniasis in pigeons from which the resistant T. gallinae strains were isolated. It was a 5-fold increase of the recommended ronidazole dosage which eliminated the infection in affected pigeons.  相似文献   

Induced Maturation and Spawning of the Chinese Catfish Clarias fuscus     

Michael J. A.  Young Arlo W.  Fast Paul G.  Olin 《Journal of the World Aquaculture Society》1989,20(1):7-11

Chinese catfish ( Clarias fuscus ) were successfully spawned in Hawaii using human chorionic gonadotropin (HCG) at dosage rates of two and four international units (IU) per gram body weight. Fish not injected with HCG did not produce viable eggs. Successful spawns with HCG occurred between May and October. Hatch rates of up to 80% were obtained during June, July, and August for those fish given either a 2 or 4 IU per gram body weight injection of HCG. Fish spawned in either May or October yielded significantly higher hatch rates when injected with 4 rather than 2 IU per gram body weight. Fish held at elevated temperatures (28 to 30 C) prior to the normal spawning season developed significantly larger oocyte diameters, 60 days earlier than fish held under ambient temperature conditions (21.5 to 24 C). Photoperiod manipulation at ambient temperature conditions was associated with earlier oocyte maturation, but photoperiod effects were much less important than temperature.  相似文献   

Variability of serum bile acid concentrations over time in dairy cattle, and effect of feed deprivation on the variability.     

E G Pearson  A M Craig  K Rowe 《American journal of veterinary research》1992,53(10):1780-1783

Twelve nonlactating dairy cows, free of signs of liver disease and with normal serum activities of liver-derived enzymes and normal liver biopsy tissue, were examined over a 72-hour period for serum total bile acid concentrations. The cattle were fed hay twice daily, and blood samples were obtained every hour for 24 hours, every other hour for 24 hours, then every hour for 24 hours. After 3 weeks, the study was repeated on 6 of the cattle, thus providing data for eighteen 72-hour periods. Serum bile acid concentration varied greatly over the 72 hours, with the range being from one third to 3 times the median. There were variations by as much as 60 mumol/L from 1 hour to the next. After another 3 weeks, 8 of the cattle were deprived of hay for 48 hours and then fed hay morning and afternoon of the third (last) day of the study. There was no significant reduction in bile acid concentration after withholding the hay, but the variability was reduced (P = 0.02) during the last 20 hours of the hay-deprivation period. In 3 ancillary studies, serum bile acid concentrations were examined over a 48-hour period in 2 cows in early lactation, 3 cows in midlactation, and two 6-month-old heifers. The cows were fed hay and grain twice daily, and the heifers were fed only hay twice daily. In comparison with values for the 12 nonlactating cows fed hay twice daily, mean serum bile acid concentration in the recently freshened cows was significantly (P < 0.002) higher (62.9 vs 22.0 mumol/L).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Relationship of common avian pathogen antibody titers in so-called chicken anemia agent (CAA)-antibody-positive chicks to titers in CAA-antibody-negative chicks.     

M A Goodwin  J Brown  M A Smeltzer  T Girshick  S L Miller  T G Dickson 《Avian diseases》1992,36(2):356-358

Antibody titers for infectious bursal disease virus (IBDV), infectious bronchitis virus, Newcastle disease virus, and reovirus from chicks with chicken anemia agent (CAA) antibodies were compared with antibody titers from their CAA-antibody-negative counterparts. These comparisons were made in 396 chickens that were 1 day, 2 weeks, 8-9 weeks, 10 weeks, 17 weeks, or 29-32 weeks old. Only one serum sample was collected from any given chick or chicken. There were no significant differences between the antibody titers at any age for any antigen, with one exception: at 29-32 weeks, the IBDV titers were higher (t = 2.62, df = 142, P less than 0.01) in chickens with CAA antibody. Although not at all likely, we believe that the observation of high IBDV antibody titers in CAA-antibody-positive chicks could have been a spurious one.  相似文献   

Monoclonal antibodies to bovine viral diarrhea virus: cross-reactivities to field isolates and hog cholera virus strains.   总被引：2，自引：1，他引：1       下载免费PDF全文

D Deregt  S R Bolin  R A Heckert    K G Loewen 《Canadian journal of veterinary research》1994,58(1):71-74

Monoclonal antibodies to bovine viral diarrhea virus (BVDV) were examined for binding with a large number of North American BVDV isolates and eight strains of the serologically related pestivirus, hog cholera virus (HCV). No single BVDV monoclonal antibody reacted with all BVDV isolates. The most cross-reactive monoclonal antibody was an anti-p80/p125 antibody which showed a positive reaction with 173 of 180 (96%) North American isolates. From a fewer number of isolates tested, one anti-gp53 monoclonal antibody also showed a high cross-reactivity (94%). All BVDV isolates showed a positive reaction with at least one of the seven monoclonal antibodies in the panel. Thus, the results indicated that a pool of these monoclonal antibodies may be used in place of polyclonal antisera for the detection of BVDV contamination of cell lines or for virus isolation. For HCV, all three anti-p80/p125 monoclonal antibodies reacted positively with all eight virus strains. In contrast, none of the anti-gp53 monoclonal antibodies were reactive to HCV strains. Thus, the anti-gp53 monoclonal antibodies may be useful for distinguishing between usually innocuous BVDV infections and the highly significant HCV infections in swine for foreign animal disease surveillance.  相似文献   

Comparative effects of mu and kappa opiate agonists on the cecocolic motility in the pony.          下载免费PDF全文

T Roger  T Bardon    Y Ruckebusch 《Canadian journal of veterinary research》1994,58(3):163-166

The electrical and mechanical activity of the large intestine and its response to administration of opiate mu and kappa agonists were assessed from electrodes and inductograph coils chronically implanted on the cecocolic segment in six ponies given a diet of hay and concentrates. Before the drugs were given, migrating complexes propagating from the cecum into the colon occurred at the rate of 1.5 to 16/hour. During this propulsive activity, the cecocolic sphincter opened and closed allowing the outflow of cecal contents and preventing the backflow of colic contents. Each pony was used as its own control and was given fentanyl (0.01 and 0.05 mg/kg of body weight, IV) and U50488H (0.1 and 0.5 mg/kg, IV) at weekly intervals. The mu agonist fentanyl elicited a marked phase of inhibition of the propulsive activity and a closure of the cecocolic sphincter that lasted one to two hours depending on the dose. The kappa agonist U50488H induced an inhibition of the short spiking activity, i.e. of the resting muscle tone. It did not disturb the occurrence of migrating complexes nor that of the openings of the cecocolic sphincter. These kappa compounds may be drugs of choice to alleviate visceral pain in colic stases without inducing delay of transit unlike mu compounds.  相似文献   

RADIOGRAPHIC DIAGNOSIS TRAUMATIC RETICULOPERITONITIS     

JoAnna  G. Toenniessen  DVM  John M.  Losonsky  DVM  MS 《Veterinary radiology & ultrasound》1994,35(1):22-23

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