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Abstract

Objective—To determine whether feeding a commercial anionic dietary supplement as a urinary acidifier to male goats may be useful for management of urolithiasis.

Animals—8 adult sexually intact male Toggenburg, Saanen, and Nubian goats.

Procedure—Goats were randomly assigned by age-, breed-, and weight-matched pairs to an oat or grass hay diet that was fed for 12 days. On days 13 to 14 (early sample collection time before supplementation), measurements were made of blood and urine sodium, potassium, calcium, magnesium, chloride, phosphorus, and sulfur concentrations; blood and urine pH; urine production; and water consumption. During the next 28 days, the anionic dietary supplement was added to the oat and grass hay diets to achieve a dietary cation-anion difference of 0 mEq/100g of dry matter. Blood and urine samples were analyzed during dietary supplementation on days 12 to 13 (middle sample collection time) and 27 to 28 (late sample collection time).

Results—Blood bicarbonate, pH, and urine pH of goats fed grass hay and goats fed oat hay were significantly decreased during the middle and late sample collection times, compared with the early sample collection time. Water consumption and urine production in all goats increased significantly during the late sample collection time, compared with the early sample collection time.

Conclusions and Clinical Relevance—The anionic dietary supplement used in our study increases urine volume, alters urine ion concentrations, and is an efficacious urinary acidifier in goats. Goats treated with prolonged anionic dietary supplementation should be monitored for secondary osteoporosis from chronic urinary calcium loss. (Am J Vet Res 2004;65:1391–1397)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To explore the use of urethral endoscopy and laser lithotripsy in the diagnosis and management of urolithiasis in goats and pot-bellied pigs.

Design—Prospective clinical study.

Animals—16 male goats and 6 male pot-bellied pigs with dysuria.

Procedure—Abdominal ultrasonography and urethral endoscopy were performed on all 22 animals. Endoscopic-guided holmium:yttrium-aluminum-garnet laser lithotripsy was performed in 3 goats and 2 pot-bellied pigs.

Results—Urolithiasis was identified in 15 goats and 5 pot-bellied pigs. Primary urinary bladder paralysis and cystitis were identified in the remaining pot-bellied pig and goat. Mean bladder diameters of obstructed small- and large-breed goats were 7 and 9.5 cm, respectively. The mean bladder diameter of obstructed pot-bellied pigs was 9.5 cm. Five of 20 animals with obstructive urolithiasis had severe urethral necrosis or stricture formation at the time of urethroscopy. All of these animals were euthanatized within 6 months because of persistent dysuria. When used, laser lithotripsy successfully fractured the distally located obstructing stones in the 3 goats and 2 pot-bellied pigs.

Conclusions and Clinical Relevance—Urethral endoscopy is useful for evaluating urethral patency in goats and pot-bellied pigs. Examination of the urethral mucosa following relief of urethral obstructions aids in the assessment of the long-term prognosis for urethral stricture. Urethral endoscopy also expands the therapeutic options for management of urolithiasis by providing a route for conducting laser lithotripsy. Laser lithotripsy proved to be safe and effective for clearing distally located calculi refractory to removal by traditional urethral flushing. Lithotripsy application is restricted to calculi lodged in the urethra. (J Am Vet Med Assoc 2002; 220:1831–1834)

Full access
in Journal of the American Veterinary Medical Association

Summary

Serologic testing to detect persistent IgG titer directed at Salmonella lipopolysaccharide (lps) has proven useful in detecting Salmonella carrier cattle without clinical signs of disease and in seroepidemiologic studies. Although little cross-reactivity exists between most Salmonella serogroups, groups B (O1, 4 [5], 12) and D (O1, 9, 12) share somatic (lps cell wall) antigens O1 and O12, which results in some cross-reactions. This may be unimportant in most instances, because group-B and group-D carriers need to be identified and culled. It may be desirable in some situations, such as when trying to control S dublin, to determine which serogroup is present in a given herd. For this reason, a procedure to produce a pure O9 group-D antigen was developed.

Salmonella dublin (group D) was grown by use of standard procedures, and lps was extracted by use of the phenol-water method. The lps was then oxidized with sodium periodate, dialyzed, reduced with sodium borohydride, cleaved with hydrochloric acid, and again dialyzed. This procedure successfully cleaved the saccharides comprising O antigens 1 and 12, leaving a pure O9 elisa antigen. Sera from cattle vaccinated or naturally infected with S typhimurium, S agona, and S schwarzengrund (all group B), S montevideo (group C1), and S dublin (group D) were tested by elisa, using modified and unmodified antigens. When the elisa antigen used was the chemically modified (pure O9) group-D antigen, elimination of cross-reactions confirmed the structural loss of cross-reacting O1 and O12 antigens.

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

Summary

Cows and calves from a 1,600-cow drylot dairy were screened for IgG antibodies to Salmonella dublin lipopolysaccharide (lps), using an indirect elisa. The elisa was performed on milk samples from lactating cows and on sera from nonlactating cows and calves. Fecal samples were collected from calves and nonlactating cows for culture of Salmonella spp. All seropositive cattle were retested by culture and elisa 5 times at monthly intervals or until antibody concentration decreased. None of the cattle remained culture-positive and seronegative. Prior to and during the sample collection period, approximately 30% of calves < 8 weeks old died of S dublin infection. Vaccination of cows with a killed S dublin/S typhimurium vaccine at cessation of lactation was a routine management practice. The elisa-determined IgG response to vaccination had decreased by 50 days after vaccination.

Eight cows and 5 calves that maintained a high serologic response to S dublin were purchased and moved to a research facility for 6 months of intensive monitoring. Lactating cows were milked twice daily, and culture of milk and feces for Salmonella spp was performed 5 times/wk. Serum IgG antibodies to S dublin lps were measured weekly, using elisa. At the end of 6 months, all 13 cattle were necropsied and tissues were obtained for culture of Salmonella spp. All 8 cows and 5 calves maintained persistently high elisa titer for the 6 months of testing, and shed S dublin in the milk and/or feces during the same period. On this basis, they were termed S dublin carriers. Salmonella dublin was isolated from mammary tissue of 2 calves at necropsy, indicating that bacteremia may be a mode of mammary infection by S dublin.

Results of the study indicated serologic testing can be used successfully on a large dairy to identify S dublin carrier cattle. Using initial milk screening, 42 of 1,268 lactating cows were identified as suspect, requiring repeated serologic testing. One nonlactating cow, 7 of the 42 suspect lactating cows, and 5 of the 222 calves maintained an IgG response, and were found to be S dublin carriers. Carrier cows shed S dublin in 3.35% of fecal samples and 2.51% of milk samples, and carrier calves shed S dublin in 17.26% of fecal samples.

Free access
in American Journal of Veterinary Research

Objective

To identify risk factors for nosocomial Salmonella infections among hospitalized horses.

Design

Longitudinal study.

Animals

1,583 horses hospitalized in an intensive care unit between January 1992 and June 1996.

Procedure

Survivor functions were used to estimate time to shedding salmonellae for various Salmonella serotypes. Survival analysis was then used to determine how variables associated with patient management, environmental conditions, hospital conditions, and other disease processes affected the risk of nosocomial Salmonella infection.

Results

78 horses shed Salmonella organisms: 35 shed Salmonella krefeld, 26 shed S typhimurium, and 17 shed other Salmonella serotypes. Mean time from admission to shedding was significantly longer for horses shedding S krefeld or S typhimurium than for horses shedding other Salmonella serotypes. Therefore, infection with S krefeld or S typhimurium was considered nosocomial. Seven variables were found to be significantly associated with risk of nosocomial Salmonella infection: mean number of horses in the hospital shedding S krefeld during the 4 days prior to and the day of admission, mean number of horses shedding S typhimurium during this period, a diagnosis of large colon impaction, withholding feed, number of days fed bran mash, duration of treatment with potassium penicillin G, and mean daily ambient temperature.

Clinical Implications

Results suggest that risk of nosocomial Salmomella infections is greater for horses with large colon impactions. In addition to implementing hospital protocols that minimize cross contamination between patients, strategies to reduce the risk of nosocomial Salmonella infection should include minimizing use of potassium penicillin G and regulation of environmental temperature in the hospital. (J Am Vet Med Assoc 1999;214:1511-1516)

Free access
in Journal of the American Veterinary Medical Association

Objectives

To predict mortality of horses by use of clinical data from the first day of hospitalization, to determine whether fecal shedding of Salmonella organisms is related to severity of clinical disease, and to determine the impact of fecal shedding of Salmonella organisms on mortality.

Design

Prospective study.

Animals

1,446 hospitalized horses.

Procedure

Medical information was obtained from horses hospitalized in an intensive care unit or isolation facility during a 4.5-year period. A model was created to predict mortality, using covariates determined on the day of admission. Predicted mortality provided a measure of clinical condition. Predicted mortality was compared between horses that were and were not shedding Salmonella organisms in their feces to determine whether shedding was associated with severity of disease. Predicted and observed mortality between horses were also compared to evaluate the association between fecal shedding of Salmonella organisms and mortality.

Results

92 horses were identified as shedding Salmonella organisms. In a multivariable model, 4 variables (heart rate, respiratory rate, rectal temperature, and clinical management) were associated with mortality. A higher predicted probability of death was observed in horses that shed Salmonella krefeld or more than 1 serotype. Relative risk (RR) of mortality was high for horses shedding S typhimurium (RR, 1.94; 95% confidence interval, 1.04 to 3.59) and multiple serotypes (RR, 4.75; 95% confidence interval, 2.29 to 9.84). When the clinical condition (ie, prior predicted probability of death) was taken into consideration, fecal shedding of Salmonella organisms was not significantly associated with mortality.

Clinical Implications

In this horse population, fecal shedding of S krefeld was associated with more severe clinical conditions at the time of admission; however, fecal shedding of Salmonella organisms during hospitalization did not alter predicted mortality. (J Am Vet Med Assoc 1998;213:1162-1166)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine susceptibility of cattle to infection with Ehrlichia equi and the agent of human granulocytic ehrlichiosis (HGE).

Design—Experimental disease and prevalence survey.

Animals—6 cattle, 2 horses, and 2,725 serum samples from healthy cattle.

Procedure—2 cattle and 1 horse were inoculated with E equi, 2 cattle and 1 horse were inoculated with the HGE agent, and 2 cattle served as sham-inoculated controls; inoculated animals were evaluated via clinical, hematologic, serologic, and real-time polymerase chain reaction tests. Prevalence of antibodies against E equi in 2,725 healthy cattle was determined by use of an indirect immunofluorescent technique.

Results—No abnormal clinical or hematologic findings or inclusion bodies within granulocytes were observed in the cattle after inoculation, and results of all polymerase chain reaction tests were negative. Seroconversion in inoculated cattle developed 10 to 12 days after inoculation (reciprocal titers, 160). Both horses developed clinical signs of ehrlichiosis. Five of 2,725 (0.18%) cattle were seropositive for E equi, with titers ranging from 20 to 80. All seropositive cattle originated from the same tick-rich region in the Sierra Nevada foothills.

Conclusions and Clinical Relevance—Results suggest that cattle are not susceptible to infection with E equi or the agent of HGE and that prevalence of exposure to E equi in healthy cattle is low. Therefore, E equi and the agent of HGE are likely of negligible importance for cattle in North America. (J Am Vet Med Assoc 2001;218:1160–1162)

Full access
in Journal of the American Veterinary Medical Association