Experimental production of infectious bovine keratoconjunctivitis: comparison of serological and immunological responses using pili fractions of Moraxella bovis.

The effect of vaccinating cattle and mice on the development of keratoconjunctivitis was studied. Cattle were vaccinated with whole cells, disrupted cells and pili fractions of three strains of Moraxella bovis. Mice were vaccinated with pili fractions of three strains. The resistance of all vaccinated animals was challenged with virulent cultures of M. bovis. In an attempt to correlate the response seen after vaccination and challenge with a pili fraction of M. bovis, vaccinated cattle and mice were grouped on the basis of signs of disease manifested and compared on the basis of serological responses. Serum samples were tested for antibodies by a gel diffusion precipitin test. A greater number of the sera of resistant cattle had antibodies to the homologous pili antigen than those of vaccinated nonresistant cattle. Cattle vaccinated with disrupted cells were not resistant to infectious bovine kerato-conjuctivitis and their sera lacked antibodies against the pili antigens. Vaccinated mice were more resistant to infectious bovine kerato-conjuctivitis and their sera lacked antibodies against the pili antigens. Vaccinated mice were more resistant to challenge exposure by homologous than heterologous cultures. A greater number of the sera of resistant mice had antibodies to pili antigens than nonresistant mice.     

NOCTURNAL ACTIVITY OF BIRDS ON SHRIMP MARICULTURE PONDS

Birds can reduce production of shrimp in mariculture grow-out ponds through predation and competition for feed. This study involved weekly nocturnal enumeration of bird populations and observation of nocturnal avian habits on a series of 0.1 ha experimental ponds at the Texas A&M University Shrimp Mariculture Facility at Corpus Christi, Texas. Observations were conducted hourly from sunset to sunrise during October through December 1980. The rate of predation was evaluated every three hours by comparing the number of feeding attempts to the number of successful prey captures over a known time period. Gulls (Family Laridae) acted primarily as competitors for feed. Active feeding by gulls was restricted to daylight hours, consequently feed loss decreased when the feed was distributed at or after dusk. Major preadatory birds included herons and egrets (F. Ardeidae), migratory ducks (F. Anatidae), and, to a lesser extent, grebes (F. Podicipedidae) and shorebirds (Order Charadriiformes). Bird predation decreased pond production by 75% in some ponds.     

Antegrade pyelography for suspected ureteral obstruction in cats: 11 cases (1995-2001)

OBJECTIVE: o determine sensitivity and specificity of radiography, ultrasonography, and antegrade pyelography for detection of ureteral obstructions in cats. DESIGN: Retrospective study. ANIMALS: 11 cats. PROCEDURE: Medical records of cats that had radiography, ultrasonography, and antegrade pyelography performed for suspected ureteral obstructions were examined. Ultrasound-guided pyelocentesis and fluoroscopic-assisted antegrade pyelography were performed on 18 kidneys in 11 cats. Obstructive ureteral lesions were confirmed in all cats by surgical or necropsy examination. Sensitivity and specificity of survey radiography, ultrasonography, and antegrade pyelography for identification of ureteral obstructions were calculated. Surgical or necropsy findings were used as the standard for comparison. RESULTS: All cats were azotemic. Mean +/- SD serum creatinine and BUN concentrations were 10.2 +/- 6.1 and 149 +/- 82 mg/dL, respectively. Fifteen of 18 ureters were found to be obstructed at surgery or necropsy. Sensitivity and specificity were 60 and 100% for radiography and 100 and 33% for ultrasonography, respectively, in identification of ureteral obstructions. Leakage of contrast material developed in 8 of 18 kidneys during antegrade pyelography and prevented diagnostic interpretation in 5 of 18 studies. For the 13 diagnostic studies, specificity and sensitivity were 100% by use of the antegrade pyelography technique. Correct identification of the anatomic location of the ureteral obstruction was obtained in 100% of diagnostic antegrade pyelography studies and in 60% of radiography or ultrasonography studies. CONCLUSIONS AND CLINICAL RELEVANCE: Antegrade pyelography can be a useful alternative in the diagnosis and localization of ureteral obstructions in azotemic cats, although leakage of contrast material may prevent interpretation of the study.     

Use of a hydroxyapatite orbital implant in a cosmetic corneoscleral prosthesis after enucleation in a horse

A hydroxyapatite orbital implant was used after enucleation of an eye from a 5-year-old performance horse. A custom-made corneoscleral prosthesis was made and fitted over the hydroxyapatite implant. The implant and surgery were well tolerated. Placement of a cosmetic prosthesis is desired after enucleation of equine eyes to allow horses to return to competition. Synthetic spheres consisting of methylmethacrylate or silicone have been used, although reported complications have included extrusion, infection, and poor cosmetic results. Hydroxyapatite orbital implants made from marine coral allow vascular and fibrous tissue growth from the host orbit into the implant, which decreases the possibility of implant extrusion or infection and allows enhanced healing of defects in the overlying conjunctiva. Extraocular muscle fixation onto the implant permits motility and assists in the prevention of implant extrusion.     

Immunogenicity of bovine parainfluenza type 3 virus proteins encapsulated in nanoparticle vaccines,following intranasal administration to mice

Stimulation of long lasting, protective immunity to respiratory viruses is often difficult to achieve with conventional respiratory vaccines. Polymeric nanoparticles, incorporating viral proteins have been shown to offer sustained release of antigen, with consequent prolongued stimulation of the respiratory immune system. In this paper the efficacy of two nanoparticle vaccines (poly-lactide-co-glycolide, PLGA; polymethylmethacrylate, PMMA), incorporating proteins of bovine parainfluenza type 3 virus (BPI-3) was investigated. As a preliminary to experiments in calves, it was considered essential to demonstrate immunogenicity of the experimental vaccine in mice. Mice immunised with PLGA nanoparticles, containing BPI-3 proteins, developed higher levels of virus-specific antibody than mice immunised with the PMMA vaccine or with soluble viral proteins alone. Immunoblotting using serum from the vaccinated mice, demonstrated strong reactions against the major BPI-3 proteins.     

Pulmonary embolism associated with canine total hip replacement

OBJECTIVE: To determine by pulmonary perfusion scans and ultrasonography if embolemia occurs during total hip replacement (THR) surgery in dogs. STUDY DESIGN: Prospective clinical study. ANIMALS: Forty client-owned dogs that had THR surgery. METHODS: Thoracic radiographs were taken immediately after THR and immediately after completion of (99m)Tc-MAA lung scans. Scintigraphy was performed in 28 dogs, 48 hours after THR. Intraoperative ultrasonography (intercostal or transesophageal) was performed in another 12 dogs that had THR. The right atrium and ventricle and pulmonary outflow tract were observed during and for 5 to 8 minutes after femoral component insertion into medullary canals prepared by reaming, and lavage and aspiration of debris before filling with polymethylmethacrylate in dough stage. A modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) classification system was used to evaluate lung scans. RESULTS: No pulmonary radiographic abnormalities were identified. Segmental and subsegmental perfusion defects occurred in 23 (82%) dogs and were classified as severe in 9 (32%) dogs, moderate in 11, and mild in 3. There was no particular lobe predilection. Patchy mulberry-appearing defects, indicative of fat embolism, were most common. Embolemia was observed by ultrasound in 10 dogs. Variable-sized particles occurred in 8 dogs, particles and bubbles in 2 dogs, and no emboli were observed in 2 dogs. Embolemia was observed within 10 seconds after femoral stem insertion and lasted < 1 minute. Pneumoemboli remained in the right atrium for > 8 minutes before dislodgement. CONCLUSIONS: Embolemia of either air, particles, or both occurs in most dogs during THR surgery. CLINICAL RELEVANCE: Most dogs seemingly spontaneously recover from pulmonary embolism that occurs during THR. The risk of clinical complications from this pulmonary embolism should be taken seriously, even though the exact morbidity and mortality rates are unknown.     

Canine choroidal melanoma with metastases

A 3-year-old-female, spayed Golden Retriever was examined for a unilateral retinal detachment with exophthalmos. Ultrasonographically, a mass was detected with intra- and extraocular extension. The orbit was exenterated and the dog recovered uneventfully. Histopathologic diagnosis was a primary choroidal melanoma with orbital extension, however, the behavioral and cytologic features were benign. Routine examinations postsurgically were nonremarkable. Twenty-one months after surgery the dog was euthanized for respiratory collapse with radiographic signs of metastasis. Necropsy revealed black lesions in the lung and liver. Histopathologic diagnosis was metastatic melanoma with morphology and behavior identical to the primary choroidal melanoma. This is the first definitive case of a canine choroidal melanoma with metastasis.     

Diet and lifestyle variables as risk factors for chronic renal failure in pet cats

A case-control study examining diet and lifestyle variables to generate hypotheses of potential risk factors for chronic renal failure in pet cats was conducted in five private practices in Texas, USA and at the Texas A&M University Veterinary Medical Teaching Hospital. A telephone questionnaire was used to gather information from owners of 38 cats newly diagnosed with CRF between December 1994 and 1995 and from owners of 56 control cats. Factor analysis was used to determine whether composite variables should be constructed to summarize the nutritional predictors adequately. The composite variables and other lifestyle variables were analyzed with logistic-regression. Three final exploratory models were developed: ad libitum feeding with fiber; ad libitum with Factor-2 (a composite variable composed of fiber, magnesium, protein, sodium and ash); and fiber alone. Ad libitum feeding and increased ash intake were associated with increased odds of CRF; increased dietary fiber, magnesium, protein and sodium were associated with decreased odds of CRF.