Case Description—A 10-year-old Longhorn cow pregnant with a valuable fetus was evaluated because of progressive inspiratory dyspnea of 6 weeks' duration.
Clinical Findings—Physical examination findings were consistent with upper respiratory tract obstruction. A large pedunculated soft tissue mass was evident in the mid-dorsal aspect of the pharynx during palpation and endoscopic examination. Results of microscopic examination of transendoscopic fine-needle aspirates and a biopsy specimen were suggestive of a bacterial granuloma.
Treatment and Outcome—Transtracheal intubation was performed, and the mass was excised with a chain écraseur. Results of histologic examination were consistent with a diagnosis of actinobacillosis. The owner reported that the cow was doing well without any recurrence of respiratory distress 8 months after surgery.
Clinical Relevance—Findings suggested that pharyngeal granuloma resulting from actinobacillosis should be included in the differential diagnoses when examining mature cattle with upper respiratory tract obstruction and that a chain écraseur may be useful for excising soft tissue pharyngeal masses in cattle.
To characterize frontal sinusitis unrelated to standard dehorning procedures in adult beef bulls.
18 beef bulls > 2 years of age treated for frontal sinusitis at a veterinary medical teaching hospital between May 1999 and May 2014.
Medical records were reviewed. Information obtained for each bull included signalment, history, findings from physical examination and diagnostic procedures, treatment, and survival to discharge. Long-term follow-up (≥ 1 year) was obtained from owners by telephone.
18 bulls were included, and 17 were bucking bulls. Median age and duration of signs were 4.5 years and 23 days, respectively. The most common owner complaints were nonspecific signs (eg, separation from the herd, hypo- or anorexia, and weight loss; n = 10) and suspected horn or sinus infection (7). Only 8 bulls had nasal discharge, and only 7 of the 17 bulls for which the rectal temperature was recorded were febrile. Results of radiography indicated frontal sinusitis in 12 of 13 bulls, with increased opacity of the affected sinus (n = 11) noted most commonly. Seventeen bulls were discharged from the hospital alive. Long-term follow-up was obtained for 14 bulls, including 13 bucking bulls. All 14 bulls recovered fully, and 9 of the 13 bucking bulls performed well after treatment.
CONCLUSIONS AND CLINICAL RELEVANCE
Results suggested that frontal sinusitis should be considered as a differential diagnosis in beef cattle examined for nonspecific clinical signs and that, with appropriate treatment, the prognosis is good for long-term survival in affected beef cattle.
Objective—To determine the pharmacokinetics after oral administration of a single dose of ponazuril to healthy llamas.
Animals—6 healthy adult llamas.
Procedures—Ponazuril (20 mg/kg) was administered once orally to 6 llamas (day 0). Blood samples were obtained on days 0, 0.5, 1, 2, 3, 4, 5, 6, 7, 9, 11, 14, 21, 28, 35, 42, and 49. Serum ponazuril concentrations were determined by use of a validated reverse-phase high-performance liquid chromatography assay with UV absorbance detection. Pharmacokinetic parameters were derived by use of a standard noncompartmental pharmacokinetic analysis.
Results—Mean ± SD area under the serum concentration–time curve was 7,516 ± 2,750 h•mg/L, maximum serum ponazuril concentration was 23.6 ± 6.0 mg/L, and the elimination half-life was 135.5 ± 16.7 hours. Serum concentration of ponazuril peaked at 84 hours (range, 48 to 120 hours) after administration and gradually decreased but remained detectable for up to 35 days after administration. No adverse effects were observed during the study period.
Conclusions and Clinical Relevance—The rate and extent of absorption following oral administration of a single dose of ponazuril were sufficient to result in potentially effective concentrations, and the drug was tolerated well by llamas. At this dose, ponazuril resulted in serum concentrations that were high enough to be effective against various Apicomplexans on the basis of data for other species. The effective ponazuril concentration that will induce 50% inhibition of parasite growth for Eimeria macusaniensis in camelids is currently unknown.
OBJECTIVE To determine the efficacy of Bdellovibrio bacteriovorus 109J for the treatment of calves with experimentally induced infectious bovine keratoconjunctivitis (IBK).
ANIMALS 12 healthy dairy calves.
PROCEDURES For each calf, a grid keratotomy was performed on both eyes immediately before inoculation with Moraxella bovis hemolytic strain Epp63–300 (n = 11 calves) or nonhemolytic strain 12040577 (1 calf). For each calf inoculated with M bovis Epp63–300, the eyes were randomly assigned to receive an artificial tear solution with (treatment group) or without (control group) lyophilized B bacteriovorus 109J. Six doses of the assigned treatment (0.2 mL/eye, topically, q 48 h) were administered to each eye. On nontreatment days, eyes were assessed and corneal swab specimens and tear samples were collected for bacterial culture. Calves were euthanized 12 days after M bovis inoculation. The eyes were harvested for gross and histologic evaluation and bacterial culture.
RESULTS The calf inoculated with M bovis 12040577 did not develop corneal ulcers. Of the 22 eyes inoculated with M bovis Epp63–300, 18 developed corneal ulcers consistent with IBK within 48 hours after inoculation; 4 of those eyes developed secondary corneal ulcers that were not consistent with IBK. Corneal ulcer size and severity and the time required for ulcer healing did not differ between the treatment and control groups.
CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that B bacteriovorus 109J was not effective for the treatment of IBK; however, the experimental model used produced lesions that did not completely mimic naturally occurring IBK.
Objective—To determine whether antemortem core needle biopsy and fine-needle aspiration of enlarged peripheral lymph nodes could be used to distinguish between inflammation and lymphosarcoma in cattle.
Animals—25 cattle with enlarged peripheral lymph nodes.
Procedures—Antemortem biopsies of the selected lymph nodes were performed with an 18-gauge, 12-cm core needle biopsy instrument. Fine-needle aspirates were performed with a 20-gauge, 4-cm needle. Specimens were analyzed by pathologists who were unaware of clinical findings and final necropsy findings, and specimens were categorized as reactive, neoplastic, or nondiagnostic for comparison with necropsy results.
Results—Sensitivity and specificity of core needle biopsy ranged from 38% to 67% and from 80% to 25%, respectively. Sensitivity of fine-needle aspiration ranged from 41% to 53%, and specificity was 100%. Predictive values for positive test results ranged from 77% to 89% for core needle biopsy and were 100% for fine-needle aspiration. Predictive values for negative test results were low for both core needle biopsy and fine-needle aspiration.
Conclusions and Clinical Relevance—Results indicated that core needle biopsy and fineneedle aspiration can aid in the antemortem diagnosis of bovine enzootic lymphosarcoma. Results of fine-needle aspiration of enlarged peripheral lymph nodes were more specific and more predictive for a positive test result than were results of core needle biopsy.