LETHAL TOXIN NEUTRALIZING ANTIBODY RESPONSE INDUCED FOLLOWING ORAL VACCINATION WITH A MICROENCAPSULATED BACILLUS ANTHRACIS STERNE STRAIN 34F2 VACCINE PROOF-OF-CONCEPT STUDY IN WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS)

Improved methods are needed to prevent wildlife deaths from anthrax. Caused by Bacillus anthracis, naturally occurring outbreaks of anthrax are frequent but unpredictable. The commercially available veterinary vaccine is labeled for subcutaneous injection and is impractical for large-scale wildlife vaccination programs; therefore, oral vaccination is the most realistic method to control and prevent these outbreaks. We reported the induction of an anthrax-specific lethal toxin (LeTx) neutralizing antibody response in mice following oral vaccination with alginate microcapsules containing B. anthracis Sterne strain 34F2 spores, coated with poly-L-lysine (PLL) and vitelline protein B (VpB). We continued evaluating our novel vaccine formulation through this proof-of-concept study in white-tailed deer (WTD; Odocoileus virginianus; n = 9). We orally vaccinated WTD via needle-free syringe with three formulations of the encapsulated vaccine: 1) PLL-VpB-coated microcapsules with 107-8 spores/ml (n = 5), 2) PLL-VpB-coated microcapsules with 109-10 spores/ml (n = 2), and 3) PLL-coated microcapsules with 109-10 spores/ml (n = 2). Although the limited sample sizes require continued experimentation, we observed an anthrax-specific antibody response in WTD serum following oral vaccination with PLL-coated microcapsules containing 109 spores/ ml. Furthermore, this antibody response neutralized anthrax LeTx in vitro, suggesting that continued development of this vaccine may allow for realistic wildlife anthrax vaccination programs.

In Vitro Protection and Titer Duration of Anthrax-Specific Antibodies Following Subcutaneous Vaccination of White-tailed Deer (Odocoileus virginianus) with Bacillus anthracis Sterne 34F2 Strain Spores

Outbreaks of anthrax, caused by the soilborne bacterium Bacillus anthracis, are a continuous threat to free-ranging livestock and wildlife in enzootic regions of the United States, sometimes causing mass mortalities. Injectable anthrax vaccines are commercially available for use in livestock, and although hand injection is not a cost- or time-effective long-term management plan for prevention in wildlife, it may provide a tool for managers to target selectively animals of high conservation or economic value. Vaccine-induced anthrax-specific antibody responses have been reported previously in white-tailed deer (Odocoileus virginianus), but the protective nature was not determined. In this study, five white-tailed deer were subcutaneously vaccinated with one dose (1 mL) of the Anthrax Spore Vaccine. Eight blood collections by jugular venipuncture were conducted over 146 d to measure the anthrax-specific antibody response in each deer's serum over time. Antibodies were first detected by ELISA and later with toxin neutralization assays to estimate in vitro protection. Average peak absorbance by ELISA occurred at 14 d postvaccination, whereas average peak in vitro protection occurred at 28 d postvaccination. Observed in vitro protection on average for white-tailed deer after this single-dose vaccination protocol lasted 42-56 d postvaccination, although three individuals still maintained lethal toxin-neutralizing serum antibody titers out to 112 d postvaccination. Vaccination responses were variable but effective to some degree in all white-tailed deer.

Self-limiting Orbital Emphysema Following Ocular Evisceration and Demonstration of Nasolacrimal-Oropharyngeal Communication in a South African Ostrich (Struthio camelus australis)

A 25-year-old, male, sanctuary-owned, South African ostrich (Struthio camelus australis) was evaluated for orbital emphysema after evisceration of a nonvisual and chronically irritated eye. On initial ophthalmic examination, the ostrich's left eye displayed severe corneal fibrosis, broad anterior synechia, and a shallow anterior chamber, all suggestive of a previous corneal perforation. Conjunctival hyperemia and eyelid crusts were also present, reportedly associated with chronic rubbing. Evisceration of the left eye was performed by excising the eyelid margins, conjunctiva, nictitans, cornea, and intraocular contents. Four weeks postoperatively, a nonpainful, fluctuant swelling of the surgical site was noted. Trocarization of the surgical site verified orbital emphysema and served to temporarily decompress the orbit. Orbital emphysema reoccurred within 48 hours but gradually regressed without intervention over the subsequent 9 months. A Jones test was performed in the healthy, right eye and demonstrated clear communication to the oropharynx. To our knowledge, this is the first reported case of an evisceration performed on an ostrich and the first reported case of orbital emphysema in any avian species. It is probable that the emphysema noted in this case was secondary to nasolacrimal duct-oropharynx communication.

Liposarcoma arising from the mandibular bone marrow in a ferret

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Surgical treatment of egg retention in emus

We developed a surgical technique for management of retained eggs in emus. Clinical signs associated with egg retention include cessation of laying activity or failure to lay eggs, lethargy, anorexia, straining, and passing egg material, and diagnosis can be made by external palpation, abdominal radiography, and ultrasonography. The retained eggs were removed through a paramedian abdominal incision in all birds. One bird was euthanatized at surgery because of severe peritonitis resulting from uterine rupture at the site of obstruction by the retained egg. Three birds survived and were discharged from the hospital to the owners. Egg peritonitis resulting from eggs or egg remnants in the abdominal cavity was evident in the birds that survived surgery. Surgery and administration of antimicrobials were successful in resolving the peritonitis.

Proventriculotomy in ostriches: 18 cases (1990-1992)

Over a 3-year period, proventriculotomy was performed on 18 ostriches to relieve impaction of the proventriculus. Diagnosis was confirmed by abdominal palpation, abdominal radiography, and in some cases, exploratory proventriculotomy. In addition to proventriculotomy, an esophagotomy was performed in 5 birds that were debilitated to allow force-feeding during the postoperative period. The median age of ostriches treated surgically for proventricular impaction was 7.5 months (range, 3 months to 18 years). Impactions consisted of sand, rocks, or gravel in combination with grass, leaves, wood, or other fibrous materials. In 7 birds, small pieces of wire or nails were also removed from the proventriculus. In 1 bird, a large metal punch was removed via the proventriculotomy. Six ostriches died at the hospital in the immediate postoperative period. Four of these died within 24 hours of surgery. All 4 birds were emaciated and in a severely weakened condition at admission, and they continued to deteriorate after surgery. One bird died 8 days after surgery as a result of complications associated with a septic joint unrelated to the proventriculotomy procedure. Another bird was euthanatized 6 days after surgery because its condition failed to improve and the owners did not want to pursue further treatment because of expense. Follow-up information was obtained for 12 surviving ostriches 1 week to 29 months (median, 5.5 months) after they were discharged from the hospital. Four of the 12 birds died within 30 days of discharge from the hospital. The remaining 8 birds (44%) were alive at follow-up evaluation (median, 10.5 months after surgery; range, 5 to 29 months).(ABSTRACT TRUNCATED AT 250 WORDS)