An ELISA test to detect antibody to Bordetella bronchiseptica.

An enzyme-linked immunosorbent assay (ELISA) was developed to measure antibody to Bordetella bronchiseptica in dogs. The ELISA test was more rapid and sensitive and required 50 to 150 times less antigen than the amount of antigen required for the conventional tube agglutination test. A survey of 50 canine serum samples using ELISA suggested that 8% of all sera had titers greater than 1:64, 56% had titers of 1:8 to 1:64, and 36% had titers of less than 1:8. The mean titer of survey sera was 1:46 and the median titer was 1:16. Serum antibody responses in dogs inoculated with a commercially available bacterin were compared with responses in dogs inoculated with experimental endotoxin depleted bacterin.

Novel indirect fluorescent antibody test for Lyme disease.

An indirect fluorescent antibody (IFA) test was developed using a novel format of Borrelia burgdorferi organisms adhered to a monolayer of cultured endothelial cells derived from an equine tumor. Sensitivity and specificity of the new IFA test for detecting anti-B, burgdorferi antibodies were evaluated using sera from dogs inoculated with live B. burgdorferi or vaccinated with B. burgdorferi bacterin or leptobacterins and from unvaccinated specific-pathogen-free (SPF) dogs. To compare the new IFA test with existing tests, serum samples were submitted to independent laboratories to be tested by enzyme-linked immunosorbent assay (ELISA) and a traditional IFA test. Samples were also tested with 2 commercially available membrane-bound ELISA kits. Both Borrelia-inoculated dogs and dogs vaccinated with B. burgdorferi bacterin developed levels of antibody detectable by the new IFA test. Dogs vaccinated with a combination canine vaccine or leptobacterin for food animal use developed detectable levels of antibody against Leptospira but remained seronegative for Borrelia by the new IFA test, as did the unvaccinated SPF dogs. The new IFA test was sensitive, detecting antibodies against B. burgdorferi as early as 7 days postinoculation. It was also specific, showing no cross-reactivity with anti-Leptospira antibodies induced by vaccination with leptobacterins. The new IFA test compared favorably with both the standardized traditional IFA test and ELISA. Results from both membrane-bound ELISA kits were not consistent when compared with each other or with the new IFA test. The new IFA test had low nonspecific fluorescence, which made it easier to evaluate and reduced the human error and variability of test results.

Further characterization of the biology of Hammondia heydorni.

Hammondia heydorni oocysts, recovered from the diarrheic feces of a dog suffering from corticosteroid toxicosis, were sporulated and characterized morphometrically. Sporulated H. heydorni oocysts were administered to three dogs, five goats, a calf and three guinea pigs, and tissues from these inoculated animals fed to coccidia-free dogs to determine species susceptibility to H. heydorni. Morphometric characteristics of H. heydorni oocysts were similar to previous descriptions. Oocysts were not excreted in the feces of dogs inoculated with oocysts. Dogs fed tissues from goats killed 14, 28 or 42 days after inoculation (d.a.i.) with oocysts excreted H. heydorni oocysts in their feces after consuming goat tissues. Dogs fed tissues from a calf killed at 28 d.a.i., and from goats killed 21 and 56 d.a.i., did not excrete oocysts in their feces. Developmental stages of H. heydorni were not observed in histologic sections of tissues from any of the animals.

Seroprevalence of Borrelia burgdorferi in dogs in Alabama, USA.

A random sample of private small-animal practices in Alabama submitted sera from dogs with known tick contact. A total of 579 samples from the three geographic regions of the state were collected (58% of the targeted sample size). Sera were screened for antibodies to Borrelia burgdorferi using an indirect fluorescent antibody (IFA) test which had a sensitivity and specificity of greater than 90%. Anti-B burgdorferi titers of > or = 1:64 were considered to be positive, based on results from B. burgdorferi-inoculated dogs. Ten of the 579 samples (1.7%) were positive, and titers ranged from 1:64 to 1:512. Seropositive dogs were found throughbout the state, and there was no significant difference in seroprevalence by region (Mantel-Haenszel chi 2, P = 0.85). These results indicate that the seroprevalence for canine Lyme disease in Alabama is low and that use of the canine Lyme disease vaccine is not justified.

Anosmia associated with canine distemper.

The sense of smell in dogs infected with canine distemper virus (CDV) was examined by use of EEG olfactometry, behavioral olfactometry, and electro-olfactography. Infection with CDV was confirmed by a direct immunofluorescence technique in 8 active cases and was suggested by clinical history compatible with canine distemper 10 to 26 weeks earlier in 6 cases. Pathologic alterations of the olfactory mucosa in 3 clinically affected dogs was examined by light microscopy. Infection with CDV was found to be associated with anosmia and lack of recorded responses on electro-olfactogram in 8 of 8 dogs with clinical signs of acute distemper from naturally acquired infections. Anosmia was found in 5 of 6 dogs that had recovered from acute distemper 10 to 26 weeks earlier. The sixth dog had hyposmia, with abnormalities on the electro-olfactogram. Histologic examination was not performed on the 6 dogs that had recovered. Histologic lesions observed at necropsy in 3 dogs that had had clinical signs of acute distemper were those of subacute purulent rhinitis and atrophy of the olfactory epithelium. Altered olfactory function could be explained by mucopurulent exudate blocking odors from olfactory receptors in the acutely affected dogs, but alteration of olfactory function in the dogs that had recovered without clinical evidence of rhinitis could not be explained.

Dysfunction of sense of smell caused by canine parainfluenza virus infection in dogs.

Olfactory function of 5 dogs that were naturally infected with canine parainfluenza virus and of 4 dogs that were inoculated with the C958 strain of canine parainfluenza virus was evaluated. Except for one dog that was inoculated, the threshold for detection of benzaldehyde and/or eugenol was found to be excessively high during the course of the disease, as determined by electroencephalographic and behavioral olfactometry. In experimentally infected dogs, an increase in threshold developed in the absence of other clinical signs of disease. Changes were not observed in electro-olfactograms recorded throughout the study. Olfactory thresholds returned to normal after the disappearance of clinical signs of disease in the naturally infected dogs. Necropsies and histologic examinations performed during the course of the disease did not reveal abnormalities of the olfactory mucosa.

Experimental infection of gray foxes (Urocyon cinereoargenteus) with Brucella abortus.

Ten gray foxes, eight principals that were fed approximately 4.4 X 10(10) colony forming units of Brucella abortus strain 2308 and two controls, were examined for serologic responses and tissue distribution of the organisms. Blood sera from each fox were tested on the day of exposure and at seven weekly intervals for antibodies to B. abortus, using the brucellosis card, standard tube agglutination, 2-mercaptoethanol and rivanol tests. Control foxes were serologically negative for all tests throughout the study and the principals were negative prior to exposure. On days 14, 21 and 28, the eight principals had positive card reactions and greater than or equal to 1:100 tube agglutination titers. After 28 days, the titers receded; and by day 49, three principals had negative card reactions and one of these was negative for all tests. Brucella abortus was isolated from one or more lymph nodes from seven of eight principals including the one which was seronegative. The bacterium was not isolated from lungs, livers, spleens, kidneys, uteri or testicles.

Evaluation of feline leukemia virus diagnostic tests available for in-office use by veterinarians.

Blood samples from cats were tested for FeLV group-specific antigen by use of an indirect immunofluorescent antibody (IFA) test, ELISA, or both. Several ELISA kits were evaluated as they would be used in a veterinary clinic, and some ELISA kits were compared with an IFA test for agreement of results. Good agreement of results was evident among the commercially available ELISA kits; results for most blood samples were clearly negative or decidely positive. Occasionally, test results were equivocal and retesting was necessary to obtain clear interpretation. Negative results are highly reliable, which makes ELISA valuable screening tests for FeLV in healthy cats. Results of tests on blood from healthy cats in Alabama indicated positivity rate of 4.0% in 1978 with an IFA test and 4.8% with ELISA in 1988 through 1989. Infection rate in sick cats ranged from 11.6 to 35.8%. The frequency of positive test results for FeLV in cats tested at Auburn University decreased from a 5-year average of 27.7% during 1980 through 1984 to a 5-year average of 14.9% during 1986 through 1990; the rate in 1990 was 11.6%.

Electrophoretic determination of albumin and gamma globulin concentrations in the cerebrospinal fluid of dogs with encephalomyelitis attributable to canine distemper virus infection: 13 cases (1980-1987).

Thirteen dogs with encephalomyelitis attributable to canine distemper virus infection were classified into 3 groups on the basis of histopathologic evidence of virus-induced lesions in CNS tissue. Analysis of data indicated a similarity within groups when arranged by age, clinical neurologic signs, and alterations in the CSF electrophoretic protein values. Comparison with results in dogs with experimentally induced canine distemper encephalomyelitis suggested that when grouped by age, CSF electrophoretic values are helpful in predicting the CNS histopathologic changes in dogs with naturally acquired canine distemper encephalomyelitis.

Comparative efficacies of ivermectin, febantel, fenbendazole, and mebendazole against helminth parasites of gray foxes.

Anthelmintic efficacies of ivermectin, febantel, fenbendazole, and mebendazole were compared in 45 adult gray foxes (Urocyon cinereoargenteus) naturally infected with helminth parasites. Fecal specimens were examined one week before treatment and one week and 3 weeks after treatment with each anthelmintic, using a sucrose flotation technique. Compared with pretreatment, fewer foxes in all groups were infected with helminths one week and 3 weeks after treatment. Ivermectin, febantel, and fenbendazole more effectively eliminated helminths than did mebendazole. Parasites found were Ancylostoma sp, Capillaria aerophila, and Aelurostrongylus abstrusus and/or Filaroides osleri.

Response of gray foxes to modified live-virus canine distemper vaccines.

Ten gray foxes seronegative for canine distemper virus were vaccinated with 1 of 3 commercial modified live-virus canine distemper vaccines. Of 5 foxes receiving vaccine A (chicken tissue culture origin), 4 developed significant titers (greater than or equal to 1:100) of neutralizing antibody to canine distemper virus and remained clinically normal after vaccination. Two of 3 foxes vaccinated with vaccine B (canine cell line origin) and both foxes receiving vaccine C (canine cell line origin) died of vaccine-induced distemper. Five unvaccinated control foxes died of distemper after a known occasion for contact transmission of virus from a fox vaccinated with vaccine B. The results suggested that the chicken tissue culture origin modified live-virus canine distemper vaccine is probably safe for normal adult gray foxes, whereas the canine cell origin vaccines are hazardous. The results of this study tended to corroborate anecdotal experiences of veterinarians who have observed that gray foxes frequently die from distemper soon after vaccination with modified live-virus canine distemper vaccines.

Effect of organic N-halamines on selected membrane functions in intact Staphylococcus aureus cells.

Two N-halamine compounds, 3-chloro-4,4-dimethyl-2-oxazolidinone and 1,3-dichloro-4,4,5,5-tetramethyl-2-imidazolidinone, were compared with free chlorine as to their effects on selected membrane functions of intact Staphylococcus aureus cells. Free chlorine was found to cause a loss of permeability control, as measured by the efflux of potassium from the cells and a dramatic increase in hydrogen ion permeability, and to affect cell respiration in a nonreversible fashion, as measured by oxygen uptake. The two N-halamines were found to have very little effect on permeability to either potassium or hydrogen ions but were both found to dramatically inhibit respiration in a reversible manner. It is proposed that the first step in the disinfection process by these N-halamines is an inhibition of respiratory enzymes that, if not reversed, ultimately leads to a loss of cell viability.

Bactericidal activities of selected organic N-halamines.

The bactericidal efficacies of three organic N,N'-dihalamine disinfectants in the class of compounds termed imidazolidinones were determined for combinations of pH, temperature, and water quality treatments by using Staphylococcus aureus and Shigella boydii as test organisms. The compound 1,3-dibromo-4,4,5,5-tetramethyl-2-imidazolidinone was found to be the most rapidly acting bactericide, especially under halogen-demand-free conditions. The mixed N,N'-dihalamine 1-bromo-3-chloro-4,4,5,5-tetramethyl-2-imidazolidinone was found to be intermediate in terms of rate of disinfection, while the compound 1,3-dichloro-4,4,5,5-tetramethyl-2-imidazolidinone was observed to be the slowest acting bactericide. When overall effectiveness was judged on the basis of stability of the disinfectants along with rates of disinfection, the mixed halamine was considered to exhibit great potential for use as a disinfectant in an aqueous solution.

Bovine papular stomatitis incidence in veterinary students.

Five cases of probable bovine papular stomatitis in faculty and students in a university veterinary clinic precipitated an intensive surveillance program. A senior class of veterinary medical students was questioned at the beginning of their clinical training to determine their history of exposure to cattle and presence of lesions resembling bovine papular stomatitis. Fifty-nine of the 115 students reported having had their hands in the mouths of cattle frequently. One of the 59 had experienced a hand lesion resembling bovine papular stomatitis. This class was maintained under close surveillance for bovine papular stomatitis-like lesions during the final 12 months of their clinical experience in veterinary school. One case developed in 8483 person days spent in the three high risk areas of beef cattle service, dairy cattle service and large animal anesthesiology. These two bovine papular stomatitis cases compare in frequency with five class members who had been vaccinated as a result of exposure to rabid animals and two class members with brucella antibodies in their sera. The findings suggest bovine papular stomatitis infections are not unusual in veterinary students but the mild clinical manifestations make the condition relatively unimportant.

Feline congenital erythropoietic porphyria associated with severe anemia and renal disease. Clinical, morphologic, and biochemical studies.

A feline erythropoietic porphyria was studied in an affected female Siamese cat and 2 male offspring. The principal elevated porphyrins were Type I isomers of uroporphyrin and coproporphyrin; the porphyrin precursors, porphobilinogen and sigma-aminolevulinic acid, were also detected. Porphyrins were present in the blood and in all the viscera, teeth, bones, and excreta. There was severe macrocytic hypochromic anemia, hepatomegaly, splenomegaly, and uremia associated with a renal disease characterized by mesangial hypercellularity and proliferation (resulting in narrowing of glomerular capillaries) and ischemic tubular injury. There was thickening of tubular basement membranes and tubular epithelial lipidosis, degeneration, and necrosis. Electron microscopic studies of bone marrow and kidney revealed the presence of membrane-enclosed lamellar bodies 150 to 1000 nm in diameter in cytoplasmic and extracellular locations.

Cutaneous form of bovine papular stomatitis in man.

A cutaneous form of bovine papular stomatitis (BPS) infection was diagnosed in eight persons at the School of Veterinary Medicine at Auburn University, Auburn, Ala. The initial outbreak occurred in five persons who were involved in the care of a bull that required manual placement of an oral feeding tube. Confirmation of diagnosis was based on clinical findings, cytopathological effects in tissue culture, and isolation of typical paravaccinia virus particles in tissue culture. Transmission studies were performed successfully in three normal calves using tissue culture prepared from human biopsy material. In man, the cutaneous form of BPS infection shows gross lesions similar to the cutaneous form of contagious ecthyma ("orf") or pseudocowpox ("milkers' nodules") infection. Because BPS in cattle occurs most often without evidence of readily observable lesions, unlike contagious ecthyma in sheep or pseudocowpox in cattle, the transmission of BPS to man in the cutaneous form could occur without apparent source. The mild clinical manifestations make the condition relatively minor; however, the occasional case may have more severe lesions.

Bactericidal properties of a new water disinfectant.

The N-chloramine compound 3-chloro-4,4-dimethyl-2-oxazolidinone (agent I) has been compared with calcium hypochlorite as to its efficacy as a bactericide for the treatment of water. The study included concentration, contact time, pH, temperature, and water quality as controlled variables. The species of bacteria tested were Staphylococcus aureus, Pseudomonas aeruginosa, and Shigella boydii. In general, for highly pure, demand-free water, calcium hypochlorite was the more rapid disinfectant at a given total chlorine concentration, although for water containing a controlled amount of organic load, agent I was the better disinfectant. The differences in efficacy of each of the two disinfectants can be attributed primarily to their different stabilities in water at various controlled conditions.