Search Results

Abstract

Objective—To characterize serum biochemical abnormalities in goats with uroliths.

Design—Retrospective case-control series.

Animals—107 male goats with uroliths and 94 male goats with various nonrenal diseases (controls).

Procedures—For male goats, results of serum biochemical analyses collected from 1992 through 2003 were retrieved from computerized records, as were signalment, clinical diagnoses, and discharge status. Results of analyses for BUN, creatinine, phosphorus, calcium, Na, K, Cl, total CO₂, anion gap, and glucose were compared between goats with uroliths and control goats.

Results—Goats with uroliths had higher mean BUN, creatinine, total CO₂, K, and glucose concentrations and lower mean phosphorus, Na, and Cl concentrations than control goats, with no difference in mean calcium concentration and anion gap. Goats with uroliths had higher frequency of azotemia, hypophosphatemia, hypochloridemia, and increased total CO₂ and lower frequency of decreased total CO₂ than control goats. Urolithiasis occurred more frequently in castrated males than in sexually intact males and in dwarf African breeds than in other breeds.

Conclusions and Clinical Relevance—Goats with uroliths often had hypophosphatemia at admission. Hypochloridemic metabolic alkalosis was the most common acid-base disorder. Rupture in the urinary tract system was associated with increased prevalence of hyponatremia and hyperkalemia. Clinicians should be aware of these abnormalities when determining fluid therapy.

Abstract

Objective—To identify the Moraxella bovis cytotoxin gene.

Procedure—Hemolytic and nonhemolytic strains of M bovis were compared by use of western blotting to identify proteins unique to hemolytic strains. Oligonucleotide primers, designed on the basis of amino acid sequences of 2 tryptic peptides derived from 1 such protein and conserved regions of the C and B genes from members of the repeats in the structural toxin (RTX) family of bacterial toxins, were used to amplify cytotoxin-specific genes from M bovis genomic DNA. Recombinant proteins were expressed, and antisera against these proteins were produced in rabbits.

Results—Several proteins ranging in molecular mass from 55 to 75 kd were unique to the hemolytic strain. An open reading frame encoding a 927-amino acid protein with a predicted molecular mass of 98.8 kd was amplified from M bovis genomic DNA. The deduced amino acid sequence encoded by this open reading frame was homologous to RTX toxins. Antisera against the recombinant carboxy terminus encoded by this open reading frame neutralized hemolytic and cytolytic activities of native M bovis cytotoxin.

Conclusions and Clinical Relevance—A gene was identified in M bovis that encodes a protein with sequence homology to other RTX toxins. Results of cytotoxin neutralization assays support the hypothesis that M bovis cytotoxin is encoded by this gene and belongs in the RTX family of bacterial exoproteins. Identification of this gene and expression of recombinant cytotoxin could facilitate the development of improved vaccines against infectious bovine keratoconjunctivitis. (Am J Vet Res 2001;62:1222–1228)

Abstract

Objective—To evaluate the clinical efficacy of a single injection of tulathromycin, compared with saline (0.9% NaCl) solution-treated control calves, for treatment of induced infectious bovine keratoconjunctivitis in calves.

Design—Clinical trial.

Animals—30 Holstein bull calves ranging from 5 to 6 months old and 75 to 200 kg (165 to 440 lb) with no history of Moraxella bovis infections, no history of M bovis vaccination, and negative results for M bovis on 3 consecutive ocular bacterial cultures.

Procedures—Both eyes of each calf were infected with 1 X 10¹⁰ colony-forming units of piliated M bovis for 3 consecutive days prior to the trial. On day 0, ocular lesion scores were determined for each calf and the calves were weighed and assigned to a treatment (2.5 mg/kg [1.14 mg/lb] of body weight, SC) or control group according to a stratified random allocation based on weight and lesion score. Eyes were stained with fluorescein and photographed daily to record healing. Eyes were evaluated bacteriologically for M bovis on days 0 to 6 and at 3-day intervals thereafter.

Results—Median time to ulcer resolution in calves treated with tulathromycin was 9.1 days. More than 50% of control calves still had ulcers at the end of the trial (21 days). Moraxella sp was isolated less often from the eyes of treated calves than from the control calves. By day 10, the treated calves had lower ocular lesion scores than control calves.

Conclusions and Clinical Relevance—A single dose of tulathromycin (SC) was an effective treatment of calves with experimentally induced infectious bovine keratoconjunctivitis. The long serum half-life of tulathromycin, along with the results of this trial, suggests that tulathromycin may be a rational choice as a single-injection treatment for infectious bovine keratoconjunctivitis.

Abstract

Case Description—A closed herd of 400 mixed-breed dairy goats was examined because of a decrease in milk production and increase in mortality rate. Nine animals had died within a 1-month period.

Clinical Findings—Clinical signs were evident only in lactating goats and included anorexia and recumbency. In the most severely affected goats, signs progressed to neurologic abnormalities and death. Serum aspartate aminotransferase activity, γ-glutamyltransferase activity, and total bilirubin concentration were high in clinically affected does, but no evidence of hemolysis was found. A diagnosis of copper toxicosis was made on the basis of high liver and kidney copper concentrations and histologic evidence of hepatic necrosis. Goats were found to have been fed a mineral mix containing 3,050 ppm copper for 9 months prior to the onset of copper toxicosis. Overall, there was no consistent relationship between serum hepatic enzyme activities, serum copper concentration, and liver copper concentration.

Treatment and Outcome—Clinically affected goats were treated with penicillamine, ammonium molybdate, sodium thiosulfate, and vitamin E. Penicillamine increased urine copper excretion in treated does versus untreated control animals. An increased incidence of infectious disease was identified in the herd 9 months later. Liver vitamin E concentration was low in 10 of the 12 goats that underwent necropsy.

Clinical Relevance—Findings suggested that penicillamine may be an effective treatment for goats with copper toxicosis. Production losses months after the diagnosis was made suggested that the intoxication had a prolonged animal welfare and economic impacts.

Abstract

Objectives—To compare stability, antigenicity, and aggregation characteristics of Moraxella bovis cytolysins among isolates from geographically diverse areas.

Study Population—8 isolates of M bovis.

Procedure—Filter-sterilized broth culture supernatants of M bovis were concentrated, diafiltered, and chromatographed. The endotoxin and cytolysin activities in samples were measured. Chromatographed cytolysins of M bovis were examined by immunoblotting. Hemolytic and leukotoxic activities were measured from samples collected at each step of purification and before and after storage. Hemolysis was measured directly by use of washed bovine erythrocyte targets. Leukotoxicity was measured by use of a ⁵¹Cr release assay.

Results—Cytolysin was retained by a filter with 100-kd nominal molecular weight limit. Hemolytic activity, leukotoxic activity, and endotoxin were eluted together in void volume of a gel-filtration column (molecular mass exclusion limit = 4 × 10⁷ d). Gel-column chromatographed diafiltered retentate had the greatest specific cytolytic activity and the highest endotoxinto- protein ratio. Frozen diafiltered retentate(–80°C, 4 months) was cytolytic after thawing. Immunoblots of gel-column chromatographed cytolysin contained 4 proteins with molecular masses between 90 and 68 kd. Fractions with high lytic activities also had additional protein bands with molecular masses of 98 and 63 kd. Immunoblots of gel-column chromatographed diafiltered retentate revealed proteins with molecular masses between 90 and 68 kd.

Conclusions and Clinical Relevance—Diafiltered M bovis cytolysin is aggregated with endotoxin. Antigenicity and cytolytic activities in diafiltered retentate are conserved among M bovis isolates. Diafiltration could be useful for bulk semipurification of M bovis cytolysin. Cytolysin-enriched vaccines of M bovis could be contaminated by endotoxin. ( Am J Vet Res 2004;65:977–983)

Abstract

Objective—To determine the immunogenicity of a Moraxella bovis cytolysin-enriched vaccine for prevention of infectious bovine keratoconjunctivitis (IBK).

Animals—104 mixed-breed beef calves ranging between 4 and 8 months of age.

Procedure—Vaccines were prepared by the diafiltration of broth culture supernatant from hemolytic M bovisor or sterile media. The diafiltered retentate was combined with Quil A adjuvant. Calves were randomly assigned to receive either the cytolysin vaccine (n = 35) or, as controls, adjuvant (35) or saline (0.9% NaCl) solution (34). Eyes of all calves were examined weekly for signs of IBK for 15 weeks. Calves that developed severe IBK were treated SC with florfenicol.

Results—Cytolysin vaccine contained 4 proteins with molecular masses ranging between 65 and 90 kd. Cytolysin-vaccinated calves had fewer instances of IBK than control calves. The time of onset of corneal lesions in cytolysin-vaccinated calves that developed IBK was delayed, compared with that of calves in either control group. The cytolysin-Quil A vaccine contained endotoxin, but calves did not have clinical signs of illness after vaccination.

Conclusions and Clinical Relevance—Calves that were vaccinated with a cytolysin-enriched vaccine had some resistance to IBK. Vaccines containing concentrated diafiltered M bovis cytolysin could protect beef calves against IBK. (Am J Vet Res 2005;66:136–142)

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)

Abstract

Objective—To evaluate rumen transfaunation after surgical correction of left-sided displacement of the abomasum (LDA) in cows.

Design—Prospective clinical trial.

Animals—20 multiparous cows with LDA.

Procedures—Cows with LDA were treated surgically (day 0). On days 0 (immediately after surgery) and 1, 10 cows each received 10 L of rumen fluid (transfaunated group) or 10 L of water (control group) via a stomach tube. Postoperative dietary dry-matter intake and milk yield of each cow were recorded daily for 5 days, beginning immediately after surgery. Blood and rumen fluid samples were collected prior to surgery and on days 1, 3, and 5 after surgery. Serum nonesterified fatty acid and β-hydroxybutyrate concentrations were measured. Volatile fatty acid and ammonia concentrations and pH of rumen fluid were determined. Urine specimens were collected and tested for ketones at 8 AM and 4 PM. Cows with ketonuria were treated with 50% dextrose solution administered IV at the time ketonuria was first detected. Cows with ketonuria were treated twice daily until ketonuria resolved.

Results—All cows survived and completed their lactation. Daily and cumulative dry-matter intake and milk yield of cows in the transfaunated group were significantly greater than those of cows in the control group. Cows in the transfaunated group had significantly lower serum concentrations of β-hydroxybutyrate and significantly lower acetate-to-propionate ratios in rumen fluid on day 1 after surgery, compared with cows in the control group . Cows that received transfaunate required a significantly lower total volume of dextrose administered IV than control cows.

Conclusions and Clinical Relevance—Benefits of rumen transfaunation of cows after surgical correction of LDA included a lesser degree of ketonuria, greater feed intake, and higher milk yield, compared with nontransfaunated cows. (J Am Vet Med Assoc 2004;225:915–920)

Abstract

Objective—To evaluate the efficacy of ceftiofur crystalline- free acid (CCFA) administered into the posterior aspect of an ear for treatment of corneal ulceration associated with naturally occurring infectious bovine keratoconjunctivitis (IBK).

Animals—78 beef calves located at Sierra Foothills Field Station (SFS) and 52 calves located at a commercial dairy (CD). All calves were from 3 to 9 months old.

Procedure—At each site, calves were randomly allocated to 1 of 2 treatment groups by use of a block design determined by corneal ulcer size. A single dose of CCFA (6.6 mg of ceftiofur equivalents/kg, SC) was administered into the posterior aspect of a pinna. A second group of calves received a single dose of vehicle (0.03 mL/kg, SC; controls). Corneal ulcers were photographed, and clinical signs were assessed in calves every 3 to 4 days for 21 days.

Results—A positive treatment effect was detected at SFS. Results at the CD were inconclusive because ulcer healing occurred rapidly in control and CCFA-treated calves. At SFS, treatment with CCFA resulted in shorter mean healing times, smaller corneal ulcer surface area measurements, amelioration of ocular discharge and photophobia, and a 50% increase in the percentage of calves healed by day 14. After adjustment for initial corneal ulcer size, treatment with CCFA resulted in a 4-fold increase in the odds of corneal ulcer healing by day 14, compared with controls.

Conclusions and Clinical Relevance—A single dose of CCFA administered into the posterior aspect of a pinna had a positive treatment effect against naturally occurring IBK in calves with corneal ulcerations . (Am J Vet Res 2004;65:1185–1188)

Abstract

Objective—To determine the efficacy of florfenicol for treatment of calves with naturally occurring infectious bovine keratoconjunctivitis (IBK).

Design—Randomized controlled field trial.

Animals—63 beef calves and 80 dairy calves between 4 and 12 months of age.

Procedure—Calves were randomly assigned to 1 of 3 treatment groups. Calves in the SC treatment group received a single dose of florfenicol (40 mg/kg [18.2 mg/lb] of body weight), SC, on day 0. Calves in the IM treatment group received florfenicol (20 mg/kg [9.1 mg/lb]), IM, on days 0 and 2. Calves in the control group received injections of saline solution (0.9% NaCl), IM, on days 0 and 2. Calves were reevaluated every other day for 20 days after treatment.

Results—Corneal ulcers healed by day 20 in 48 of 49 (98%) calves treated with florfenicol IM, 39 of 42 (93%) calves treated with florfenicol SC, and 33 of 52 (63%) control calves.

Conclusions and Clinical Relevance—Florfenicol administered SC (1 dose) or IM (2 doses 48 hours apart) was effective for treatment of calves with naturally occurring IBK. ( J Am Vet Med Assoc 2000;216: 62–64)