Reduced microbicidal activity of peripheral mononuclear phagocytic cells infected with Pasteurella multocida

Pasteurella multocida inhibits the uptake and killing of Candida albicans and P. multocida by avian mononuclear phagocytic cells. The toxic outer membrane protein of P. multocida, which has been previously described, also inhibited the uptake and killing of C. albicans. Antibody specific for the toxic outer membrane protein reversed this effect resulting not only in an increase in uptake of C. albicans and P. multocida, but also in intracellular killing of P. multocida. This antibody, however, only partially restored killing of C. albicans. These data support the hypothesis that P. multocida is capable of intracellular survival in avian mononuclear phagocytic cells and that the toxic outer membrane protein is totally or partly responsible for this occurrence.     

Identity of Bacteroides isolates and previously named Bacteroides spp in clinical specimens of animal origin.

During the years 1984 through 1987 2,574 isolates of obligately anaerobic bacteria were isolated from samples submitted for analysis. The most common anaerobic isolates were members of the genus Bacteroides, representing 44.6% of the isolates. Of these, the most commonly isolated identifiable microorganisms were bile-resistant and nonpigmented, belonging to the B fragilis group of Bacteroides. Importantly, obvious predilections for any one species or group of Bacteroides were not apparent for animal or site (condition), except that the proportion of isolates belonging to the nonpigmented, bile-resistant group obtained from the respiratory tract was significantly (P less than 0.005) higher than that not belonging to this group. On the other hand, the proportion of isolates of the non-pigmented, bile-resistant group obtained from abscesses was significantly lower than that not belonging to this group.     

A comparison of the protein constituents of the major body compartments of the dog roundworm, Toxocara canis

An analysis of the protein profiles of intact worms and isolated tissues of adult male and female Toxocara canis worms was conducted. Soluble proteins recovered from homogenized whole specimens and dissected tissues (body wall, reproductive tract, esophagus and intestine) of T. canis adults from several different canine hosts were separated by size using gradient sodium dodecyl sulfate electrophoresis (SDS-PAGE) and visualized with silver staining. SDS-PAGE profiles of worms from different hosts were found to be virtually identical irrespective of sex or tissue type. Recovered proteins ranged in size from 3.4 to 325 kDa. As expected, variations existed between the protein profiles of different body tissues, with only slight variations between the sexes. The largest number of recovered proteins was present in the female reproductive tract extracts.     

Successful resolution of a preputial prolapse in an alpaca using medical therapy

A 2-year-old intact male alpaca was presented for a post-breeding preputial prolapse of 5 days duration. The internal lamina of the prepuce was prolapsed approximately 6 cm and the exposed preputial epithelium was edematous and necrotic. Following 7 days of medical treatment, resolution of the preputial prolapse was achieved.     

Serum resistance is correlated with encapsulation of avian strains of Pasteurella multocida

Encapsulated avian strains of Pasteurella multocida possessing an A-type capsule were shown to be resistant to the bactericidal action of turkey serum, whereas unencapsulated variants as well as other unencapsulated strains were not. Removal of the capsule from serum-resistant strain P1059-1 resulted in this strain becoming susceptible to the bactericidal effects of turkey serum. Since complement was consumed when encapsulated or unencapsulated strain P1059-1 was incubated in turkey serum, we conclude that the capsule acts to shield the outer membrane rather than prohibiting the generation of an effective membrane attack complex.     

A Clinical Trial of Probiotic Administration for Prevention of Salmonella Shedding in the Postoperative Period in Horses With Colic

The purpose of this study was to evaluate the effects of probiotic administration on the prevalence of fecal shedding of Salmonella , the prevalence of postoperative diarrhea, the length of antimicrobial therapy, and the length of the hospitalization stay during the postoperative period in horses with colic. Two commercially available probiotics for horses were used in a double-blind prospective study of 200 horses undergoing surgery for colic. Probiotic or placebo was administered PO once a day for 7 days postoperatively, and fecal cultures for Salmonella were obtained daily for 10 days. After selection of 186 patients completing the treatment protocol, the results indicated that the commercial probiotic formulations had no effect on Salmonella shedding, prevalence of diarrhea, length of antimicrobial therapy, or length of hospitalization ( P > .05). Twenty percent of the horses yielded 1 or more positive fecal cultures for Salmonella; of these horses, 74% were classified as asymptomatic shed-ders. Twenty-six percent of all horses had fluid diarrhea postoperatively, with only 12% of these horses having positive fecal cultures for Salmonella , The most common isolate was Salmonella krefeld (24 of 39 isolates). Among the different gastrointestinal disorders, horses with feed and sand impactions appeared to be more prone to shed Salmonella .     

Differentiation of field isolates of Pasteurella multocida serotype 3,4 from live vaccine strain by genotypic characterization

Fifty-five serotype 3,4 isolates of Pasteurella multocida, isolated from turkeys dead from fowl cholera, were characterized (fingerprinted) genotypically for comparison with the serotype 3,4 live fowl cholera vaccine principally used in turkeys in California. Twenty-three isolates were obtained from turkeys vaccinated with the M9 live vaccine, and 32 additional isolates were from turkeys not vaccinated for fowl cholera. Methods of characterization included restriction endonuclease analysis of chromosomal DNA and ribotyping, a technique for highlighting restriction site heterogeneity of highly conserved ribosomal RNA genes and associated sequences using a radiolabeled rRNA probe. Eight different genotypes or ribotypes were detected in these isolates by the above methods. Of 23 isolates from M9-vaccinated turkeys flocks, 19 were the same ribotype as M9. Thirty of 32 isolates recovered from unvaccinated turkeys were different ribotypes from M9. The remaining two isolates resembled M9 and were recovered from two different flocks placed in succession on a turkey farm where a flock placed previously had been vaccinated with M9, suggesting interflock transmission. Ribotyping and restriction endonuclease analysis appear to be useful tools to aid in the determination of the role that the live vaccine plays in fowl cholera epidemiology.