Search Results

You are looking at 1 - 7 of 7 items for

  • Author or Editor: Eileen Johnson x
  • Refine by Access: All Content x
Clear All Modify Search
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine effects of pituitary pars intermedia dysfunction (Cushing's disease) and age on fecal egg count and time to egg reappearance after anthelmintic treatment in horses residing in similar environments.

Design—Cross-sectional study.

Animals—29 healthy horses (4 to 35 years old) and 13 horses with PPID (13 to 33 years old).

Procedures—Fecal egg counts were performed by use of a modified Wisconsin flotation method at 2-week intervals before and after ivermectin treatment.

Results—Horses with PPID had higher fecal egg counts before and 8, 10, and 12 weeks after ivermectin treatment, compared with counts for site-matched healthy horses. There was no difference in the period for < 90% reduction in fecal egg counts between the 2 groups. Age did not affect fecal egg counts at any time point.

Conclusions and Clinical Relevance—For similar environmental conditions, horses with PPID were more likely to have higher fecal egg counts than were healthy horses. Therefore, horses with PPID may need to have a more aggressive parasite prevention program than do healthy horses. Age did not affect fecal egg counts or time to egg reappearance after anthelmintic treatment, which suggested age alone does not likely require special consideration when designing a parasite control program for adult horses.

Full access
in Journal of the American Veterinary Medical Association

Objective

To evaluate the association of herd demographics, parturition variables, stocking rate, and rotational grazing practices with the probability of fecal shedding of Cryptosporidium parvum from beef cow-calf herds in California.

Design

Cross-sectional study.

Sample Population

38 beef cow-calf operations.

Procedure

Fecal specimens were collected and examined for C parvum oocysts, using immunofluorescent microscopy. Association between various demographic and management factors and the probability of shedding C parvum were statistically evaluated.

Results

Adjusted for age and month of collection of a fecal sample, cattle from herds with a high number of young calves (≤ 2 months old) on the day of sample collection, a high stocking rate (No. of cattle/acre/mo), or a longer calving season were more likely to shed C parvum oocysts, compared with cattle from herds with fewer young calves, a lower stocking rate, or a shorter calving season. Cattle from herds with a higher number of older calves (> 2 months old) on the day of sample collection were less likely to shed C parvum oocysts, compared with cattle from herds with fewer older calves. Using our multivariate model, rotational grazing systems or season of onset of calving were not associated with shedding status for C parvum oocysts.

Conclusions and Clinical Relevance

Reproductive management that would result in a shorter calving season and use of a lower stocking rate for cattle may be associated with reduced risk of C parvum shedding. Intensive rotational grazing systems and time of year for onset of calving season apparently have little effect on reducing prevalence of oocyst shedding. (J Am Vet Med Assoc 1999;215:1833–1838)

Free access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To determine the prevalence of Alaria infection in cats and dogs in north central Oklahoma over various periods and investigate whether wild animal species in this region were also infected.

DESIGN Combined cross-sectional study and case series.

SAMPLE Results of parasitological testing of fecal samples from 5,417 client-owned dogs and 1,246 client-owned cats (2006 through 2014); fecal samples from 837 shelter or rescue dogs and 331 shelter or rescue cats (2013 and 2014) and 268 feral cats (2015); tongue or jowl samples from cadavers of 43 wild pigs, 3 opossums, and 1 raccoon; and intestinal tract segments from cadavers of 48 cats and 5 coyotes.

PROCEDURES Various parasite recovery techniques were performed to detect various Alaria stages in samples. Recovered adult trematodes and mesocercariae were used for PCR assay and sequencing of the 28S rRNA gene.

RESULTS Prevalence of Alaria infection was significantly higher in feral cats (9.0%) than in shelter or rescue cats (0.6%) and client-owned cats (1.4%) and in shelter or rescue dogs (1.8%) than in client-owned dogs (0.2%). Mesocercariae were recovered from tissue samples from 11 (26%) wild pigs and 1 opossum. Amplicon sequences from adult trematodes and mesocercariae were 100% identical to each other and 99% homologous to GenBank sequences of Alaria alata and Alaria mustelae.

CONCLUSIONS AND CLINICAL RELEVANCE Prevalence of Alaria infection in the study area has increased in dogs and cats since 1990, when infections were rare. Prevalence in wild pigs was similar to that in Eurasia, where A alata is considered an emerging zoonotic parasite.

Full access
in Journal of the American Veterinary Medical Association

Objective

To examine Escherichia coli isolates obtained from dogs dying with diarrhea for heat-labile, heat-stable, and Shiga-like toxins and for the eaeA gene, which is associated with attaching and effacing lesions.

Design

Retrospective study.

Animals

122 dogs.

Procedure

E coli isolates were tested by means of dot-blot hybridization of DNA extracts of cultured bacteria. Medical records of dogs from which E coli isolates with virulence genes had been isolated were examined, and histologic findings and evidence of intercurrent bacterial and viral infections were recorded.

Results

None of the E coli isolates obtained from these dogs produced heat-labile, heat-stable, or Shiga-like toxins; however, E coli isolates from 44 of 122 dogs were found to have the eaeA gene. Histologically, multifocal bacterial adherence to the epithelium and epithelial necrosis and detachment were seen in colonic specimens from 20 of 44 (45%) dogs. Escherichia coli was the sole pathogen identified in 15 of 44 (34%) dogs. Intercurrent pathogens, including canine parvovirus (n = 19). Clostridium perfringens (8), rotavirus (5). hookworms (3). coccidia (3). and Salmonella agona (1). were identified in the remaining 29 (66%) dogs.

Clinical Implications

Attaching and effacing E coli can be a primary or secondary pathogen in dogs with diarrhea. Antibiotic treatment is indicated in dogs with diarrhea because of the possibility that it is primarily bacterial in origin and because, even if it is primarily viral in origin, there may be secondary bacterial infection. (J Am Vet Med Assoc 1998;212:1735–1736)

Free access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To determine effects of prosthetic laryngoplasty on return to racing, performance index, and career longevity in racing Quarter Horses with recurrent laryngeal neuropathy (RLN) and to evaluate performance variables for horses with RLN undergoing prosthetic laryngoplasty, compared with a control horse population.

DESIGN Multicenter, retrospective cohort study.

ANIMALS 162 racing Quarter Horses with RLN treated with prosthetic laryngoplasty (case horses) and 324 racing Quarter Horse without RLN (control horses).

PROCEDURES Medical and race records of case and control horses examined at 5 referral centers between January 2000 and December 2015 were reviewed retrospectively. Two control horses were matched with each case horse. Return to racing, earnings, number of racing starts, performance index, and career longevity were evaluated.

RESULTS The odds of returning to racing did not differ significantly between case and control horses but decreased with increasing age. Neither racing starts nor career longevity were affected by prosthetic laryngoplasty or by RLN grade. In fact, horses undergoing laryngoplasty for treatment of RLN and horses with the lowest RLN grade before surgery had higher performance indices after the surgery, compared with indices for control horses.

CONCLUSIONS AND CLINICAL RELEVANCE The faster speeds and shorter distances raced with Quarter Horses could alter how RLN impacts respiratory variables and performance in Quarter Horses, compared with other racehorse breeds. Further study is needed to understand the impacts of RLN and surgical treatments for RLN in racing Quarter Horses.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To evaluate fecal shedding of Cryptosporidium parvum from California cow-calf herds with respect to age, geographic region, temporal effects, and association with watery feces.

Animals

Cows and calves from 38 beef cow-calf operations.

Procedure

Fecal specimens were collected and examined for C parvum oocysts, using immunofluorescent microscopy. Associations between age, geographic region, month of collection, watery feces, and likelihood of shedding C parvum were evaluated.

Results

3.9% of cattle were shedding C parvum oocysts. Prevalence of shedding among calves ranged from 0 to 13%, and was 0.6% among cattle ≥ 12 months old. The odds of shedding C parvum among 2-month-old calves were 41 times greater than among cattle > 4 months old. The odds of shedding C parvum among cattle tested in May were 8.7 times greater than among cattle tested during June, July, or August. The odds of infected individuals having watery feces were 3 to 4 times greater than for noninfected individuals, but the etiologic fraction was only 8 to 9%.

Conclusions and Clinical Relevance

Substantial fecal shedding of C parvum by cow-calf herds was limited to calves 1 to 4 months old, with low prevalence detected in older animals. Risk of contamination of watersheds with C parvum was limited to those periods when young calves were in the herd. Although the odds of having watery feces were greater for animals infected with C parvum than for noninfected animals, the low etiologic fraction suggests that most calves with watery feces were not infected with C parvum. (Am J Vet Res 1999;60: 420-425)

Free access
in American Journal of Veterinary Research