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Objective—To determine risk factors associated with hemorrhagic bowel syndrome (HBS) among dairy cattle in the United States and identify characteristics of HBS in individual cows.

Design—Cross-sectional, population-based survey.

Sample Population—A stratified random sample of 1,013 dairy operations with ≥ 30 cows located in 21 states.

Procedure—Information on management and animal health-related topics was collected with a questionnaire.

Results—HBS was estimated to have been observed on 9.1% of operations during the preceding 5 years and on 5.1% of operations during the preceding 12 months. Factors found in multivariable analysis to be associated with the occurrence of HBS during the preceding 12 months were large herd size, administration of bovine somatotropin, and routine use of milk urea nitrogen concentration to determine ration composition. Use of pasture as part of the lactating cow ration during the growing season was associated with decreased odds of HBS in operations with rolling herd average milk production ≤ 20,000 lb, whereas in operations with higher milk production, use of pasture was not associated with occurrence of HBS. For individual cows with signs consistent with HBS, the third lactation was the median of the parity distribution and the median time between parturition and the onset of clinical signs was 104 days.

Conclusions and Clinical Relevance—Results suggest that management practices implemented to achieve high milk production may increase the risk of developing HBS in dairy cattle. Increased consumption of a high-energy diet seems to be the most plausible common pathway for all of the risk factors that have been described. (J Am Vet Med Assoc 2005;226:1700–1706)

Full access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association


From 1986 to 1989, 5 desert bighorn sheep (3 Ovis canadensis mexicana and 2 O c nelsoni), ranging in age from 2 to 3 years, were exposed to a flock of exotic wild and domestic sheep to potentially achieve naturally acquired pneumonia. Pasturella multocida was isolated from nasal samples from 4 of 6 sheep randomly sampled from the flock. Bighorn sheep were exposed individually and each exposure period was a trial. Treatment before and after exposure varied and included combinations of α interferon, antibiotics, anti-inflammatory drugs, and vaccines. Treatments were chosen on the basis of recommendations of others for treating pneumonia in desert bighorn sheep as well as our own experience in sheep and cattle. Regardless of treatment used, bighorn sheep in trials 1 to 4 developed signs of pneumonia within 10 to 14 days of exposure. Bighorn sheep in trials 1 to 3 died within 11 to 17 days of initial exposure. In trial 4, the bighorn sheep was isolated from the carrier sheep for treatment of pneumonia on day 14 and died on day 30. Pasteurella multocida was isolated from lung tissue in 3 of the 4 bighorn sheep.

On the basis of results of trials 1 to 4, a more in depth clinical study was conducted in trial 5. Nasal and blood specimens were collected prior to and during trial 5 for bacteriologic culturing and serologic testing for bovine viral diarrhea virus, infectious bovine rhinotracheitis, parainfluenza-3 virus, and respiratory syncytial virus. The bighorn sheep was vaccinated with a modified-live Pasteurella haemolytica vaccine and allowed to habituate to its new facilities for 133 days before it was exposed to the carrier sheep.

Body temperature of this bighorn sheep was monitored every hour with radiotelemetry. Pneumonia was diagnosed on day 30 of exposure to the carrier sheep. Treatment consisting of long-acting oxytetracycline, sulfadimethoxine, long-acting sulfamethazine bolus, dexamethasone, and flunixin meglumine was given for 8 days and clinical improvement was detected. Acute pneumonia was again diagnosed on day 53. The bighorn sheep was removed from contact with the carrier sheep and put in isolation for a second treatment regimen. The bighorn sheep died on day 99. Pasteurella multocida was isolated from a tracheal flush and a nasal specimen obtained during the second bout of pneumonia and from lung tissue and sinuses at necropsy. Viruses were not isolated from the tracheal flush or from tissue samples collected at necropsy.

None of the carrier sheep had clinical signs of pneumonia during the trials. Bacteriologic culturing and serologic testing in the bighorn sheep and ewes prior to and during the study suggested that carrier ewes were the source of P multocida infection in the bighorn sheep. Viruses were not a predisposing factor. Chronic sinusitis following initial pneumonia was suspected to play a role in the recurrence of pneumonia in the bighorn sheep of trial 5.

Free access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association


Objective—To determine signalment, history, and clinical, necropsy, and microbiologic findings in dairy cows with hemorrhagic bowel syndrome.

Design—Retrospective study.

Animals—22 adult dairy cows from a single farm in Colorado.

Procedure—Medical records were reviewed for information on signalment, medical and reproductive history, the owner's chief complaints, results of physical examinations and ancillary diagnostic tests, treatment and response to treatment, results of microbiologic testing, and, if applicable, postmortem findings.

Results—Common clinical signs were acute signs of profound depression, decreased milk production, tachycardia, ruminal stasis, abdominal distention, and dark clotted blood in the feces. Rectal examination revealed distended loops of small intestine in 7 of 14 cows. Transabdominal ultrasonography revealed small intestinal ileus and distention in 12 of 12 cows and homogeneous echogenic intraluminal material compatible with intraluminal hemorrhage and clot formation in 4. Seven of 8 cows treated medically died; 9 of 13 cows that underwent surgery died or were euthanatized. Clostridium perfringens was isolated from fecal samples from 17 of 20 cows. The most common morphologic diagnosis at necropsy was severe necrohemorrhagic enteritis or jejunitis with intraluminal hemorrhage or blood clots. The most prominent histologic finding was severe, segmental submucosal hemorrhage and edema of the small intestine.

Conclusions and Clinical Relevance—Results confirm that in adult cattle, hemorrhagic bowel syndrome is a sporadic acute intestinal disorder characterized by intraluminal hemorrhage and obstruction of the small intestine. Clostridium perfringens was consistently isolated from the feces of affected cows. The prognosis for affected cows was grave. (J Am Vet Med Assoc 2002;221:686–689)

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in Journal of the American Veterinary Medical Association


Objective—To develop a method for percutaneous collection of fetal fluid from cattle in the late stages of gestation and determine whether bovine viral diarrhea virus (BVDV) can be isolated from such fluids.

Design—Case series.

Animals—169 pregnant beef cattle.

Procedure—Animals were restrained in a squeeze chute, and hair was clipped from a region of the right flank. Pregnancy was confirmed, and fetal fluids were identified by means of abdominal ultrasonography. Fetal fluid was collected with a spinal needle. Virus isolation was performed on fetal fluids, WBC lysates from 160 live calves, and tissues from 12 calves that died or were aborted. Blood samples collected from adult cattle were assayed with an immunoperoxidase monolayer assay.

Results—Fourteen animals aborted or delivered premature calves within 3 weeks after fetal fluid collection; however, it could not be determined whether this was a complication of the procedure or attributable to other factors. Results of BVDV isolation from fetal fluid samples were negative for 168 animals. However, a noncytopathic BVDV was isolated from fetal fluid obtained from a 2-year-old heifer; results of the immunoperoxidase assay of serum from this heifer were also positive, and a noncytopathic BVDV was isolated from tissue specimens from a stillborn calf produced by this heifer.

Conclusions and Clinical Relevance—Results suggest that fetal fluids can be collected percutaneously from cattle in the late stages of gestation and that virus isolation performed on fetal fluids can be used to identify fetuses infected with BVDV in utero. However, safety of the procedure could not be evaluated. (J Am Vet Med Assoc 2002;220:1348–1352).

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in Journal of the American Veterinary Medical Association


Objective—To compare β-hydroxybutyrate (BHB) and glucose concentrations measured with a dual-purpose point-of-care (POC) meter designed for use in humans and a laboratory biochemical analyzer (LBA) to determine whether the POC meter would be reliable for on-farm measurement of blood glucose and BHB concentrations in sheep in various environmental conditions and nutritional states.

Animals—36 pregnant mixed-breed ewes involved in a maternal feed restriction study.

Procedures—Blood samples were collected from each sheep at multiple points throughout gestation and lactation to allow for tracking of gradually increasing metabolic hardship. Whole blood glucose and BHB concentrations were measured with the POC meter and compared with serum results obtained with an LBA.

Results—464 samples were collected. Whole blood BHB concentrations measured with the POC meter compared well with LBA results, and error grid analysis showed the POC values were acceptable. Whole blood glucose concentrations measured with the POC meter had more variation, compared with LBA values, over the glucose ranges evaluated. Results of error grid analysis of POC-measured glucose concentrations were not acceptable, indicating errors likely to result in needless treatment with glucose or other supplemental energy sources in normoglycemic sheep.

Conclusions and Clinical Relevance—The POC meter was user-friendly and performed well across a wide range of conditions. The meter was adequate for detection of pregnancy toxemia in sheep via whole blood BHB concentration. Results should be interpreted with caution when the POC meter is used to measure blood glucose concentrations.

Full access
in American Journal of Veterinary Research


Objective—To compare the frequency of isolation, genotypes, and in vivo production of major lethal toxins of Clostridium perfringens in adult dairy cows affected with hemorrhagic bowel syndrome (HBS) versus left-displaced abomasum (LDA).

Design—Case-control study.

Animals—10 adult dairy cattle with HBS (cases) and 10 adult dairy cattle with LDA matched with cases by herd of origin (controls).

Procedure—Samples of gastrointestinal contents were obtained from multiple sites during surgery or necropsy examination. Each sample underwent testing for anaerobic bacteria by use of 3 culture methods. The genotype of isolates of C perfringens was determined via multiplex polymerase chain reaction assay. Major lethal toxins were detected by use of an ELISA. Data were analyzed with multivariable logistic regression and X2 analysis.

ResultsC perfringens type A and type A with the beta2 gene (A + beta2) were the only genotypes isolated. Isolation of C perfringens type A and type A + beta2 was 6.56 and 3.3 times as likely, respectively, to occur in samples from cattle with HBS than in cattle with LDA. Alpha toxin was detected in 7 of 36 samples from cases and in 0 of 32 samples from controls. Beta2 toxin was detected in 9 of 36 samples from cases and 0 of 36 samples from controls.

Conclusions and Clinical RelevanceC perfringens type A and type A + beta2 can be isolated from the gastrointestinal tract with significantly greater odds in cattle with HBS than in herdmates with LDA. Alpha and beta2 toxins were detected in samples from cows with HBS but not from cows with LDA. (J Am Vet Med Assoc 2005;227:132–138)

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in Journal of the American Veterinary Medical Association