Inbreeding and canine mammary cancer: a retrospective study.

Using files of the Animal Neoplasm Registry (ANR) in Alameda and Contra Costa Counties, California, we conducted a retrospective study to compare the degree of inbreeding in the ancestry of purebred dogs with mammary and other cancers, and of those without tumors. Wright's coefficients of inbreeding, calculated for all animals in the three groups, ranged from 0.000 to 0.535. The median inbreeding coefficients of the mammary cancer and comparison groups (consisting of other cancers) were approximately twice that of the nonneoplastic group, but neither difference was statistically significant. Dogs with mammary adenocarcinoma and mixed mammary cancer had similar degrees of inbreeding.

Quantitative light microscopic localization of [3H]naltrindole binding sites in the rat brain.

The binding of radiolabeled naltrindole ([3H]NTI), a selective delta-opioid antagonist, was characterized using receptor autoradiography. Receptor binding properties were established in brain paste slices which demonstrated one site receptor occupancy with an apparent Kd of 0.25 +/- 0.08 nM (Bmax of 597.5 fmol/mg protein). Autoradiographic localization of [3H]NTI binding sites in the rat brain revealed high densities of these sites in the cortex (layers 1-3 and 6), caudate putamen, accumbens, claustrum, and internal plexiform layer of the olfactory bulb. Moderate to low levels of specific binding were observed in the hippocampus, thalamus, and substantia gelatinosa of the spinal cord.

DNA probe for detection of serogroup O157 enterohemorrhagic Escherichia coli.

To develop a probe for the detection of serogroup O157 enterohemorrhagic Escherichia coli (EHEC), plasmid DNA extracts from 16 E. coli strains that hybridized with the CVD419 probe were screened for restriction fragments present in plasmids of serogroup O157 E. coli strains, but not in plasmids of non-O157 E. coli strains. Using a single O157:H7 E. coli strain (639I), 10 serogroup O157 E. coli specific fragments were then removed, radiolabeled and hybridized (42 degrees C) with colony blots of both groups of strains. A 2.0 kb SmaI fragment probe (VPM1) was the most specific for serogroup O157 EHEC. Using a larger set of 41 non-E. coli and 107 E. coli strains from human, animal and meat sources, VPM1 hybridized with all 49 serogroup O157 EHEC strains. None of 8 enterotoxigenic E. coli (ETEC), including serogroup O157 strains, nor any of the 41 non-E. coli with the VPM1 probe. However, this probe hybridized with 5 of 50 non-O157 E. coli which were verotoxin (VT) or CVD419 probe-positive. Increased hybridization stringency (45 degrees C) reduced the 5 false-positives to 2 negatives and 3 trace responses, which were easily distinguishable from positive responses.

Characteristics of Vero cytotoxin producing Escherichia coli associated with intestinal colonization and diarrhea in calves.

Isolates of Escherichia coli which produce Vero cytotoxin (VTEC) were obtained during 1983-1989 from calves raised in 5 north-central states of the USA. All of the calves experienced intestinal epithelial colonization by VTEC, diarrhea or both; twelve of the calves had bloody diarrhea. Twenty one isolates were serogroup O111 and the others were O103, O69, O45, 026, O5, or non-typable (4 isolates). All but one of the isolates hybridized with the CVD419 probe which identifies most VTEC strains. Thirty two isolates hybridized with the VT1 probe, 3 with both the VT1 and VT2 probes, and one with neither probe. The culture filtrate of the VT probe negative isolate was partially neutralized by SLT I monoclonal antibody. For the other isolates, the results of toxin neutralization by anti-SLT I and anti-SLT II monoclonal antibodies corresponded exactly with the VT1 and VT2 probe hybridization results. Three of the strains adhered in a localized manner to HEp-2 cells and Intestine 407 cells.

Acute lead poisoning with eosinophilic meningoencephalitis in calves on a farm receiving land application of sewage sludge.

A total of 3 cases of acute lead poisoning in calves was confirmed by atomic absorption spectrophotometric analysis of biological samples, presence of an acute lead exposure source, clinical signs of impaired vision in one case and eosinophilic meningoencephalitis in another case. One of two other calves which died approximately 2 months earlier had nervous signs and it is likely that they also had lead poisoning. Dams of two of the cases did not have elevated lead levels. Municipal sewage sludge had been applied to most fields on the farm during the preceding 5 year period. There had been approximately a doubling of the lead content in the soil; however, the foodstuffs produced on the farm had low lead concentrations. The extremely high lead levels in the abomasal contents and feces of calves eliminated sludge as the source of the lead in this acute poisoning episode. The contents of oil filters, accessible to calves but not to adult cattle, had lead levels as high as 26,922 micrograms/g and was the most likely lead source responsible for this lead intoxication. It appears that the manifestation of eosinophilic meningoencephalitis in lead poisoning cases may occur in young calves as well as in cows and in acute as well as in chronic intoxications.

Plasmid analysis and epidemiology of Salmonella enteritidis infection in three commercial layer flocks.

Ninety-six S. enteritidis isolates obtained from three commercial layer flocks in 1988-90 were examined following DNA extraction, restriction enzyme digestion, and gel electrophoresis for plasmid size profiles and restriction fragment length polymorphisms (RFLPs). The S. enteritidis isolates from the three flocks had three, eight, and two different plasmid profiles, respectively. Only four isolates from one flock lacked plasmids. A 36-megadalton (mDa) (54-kilobase) plasmid was present in 73% of the isolates, either alone or in combination with other plasmids. Isolates with only the 36-mDa plasmid had identical RFLPs. The diversity of plasmid profiles was greater than that of phage-types among isolates from the three flocks: 12 unique plasmid profiles vs. four phage-types. Mixed infections with S. enteritidis strains having distinct plasmid profiles occurred in all three flocks. Reinfection of these flocks in 1990 with one or more of the strains obtained earlier was evident, because some of the original isolates and the 1990 isolates had matching plasmid profiles and were of the same phage-types. Isolates from both environmental and tissue samples, examined from one flock, were found to share the same plasmid profile and phage-type.

Quantitative index for diagnostic surveillance of neoplasms in dogs.

The probability of detecting a neoplasm in dogs with a previous or concurrent tumor may not be the same as the probability of observing a first neoplasm in the general canine population. A population-based index was developed to quantitate the diagnostic surveillance of tumor-bearing and nontumor-bearing dogs. The index was derived from each dog's excess submissions defined as the difference between the number of tissues submitted for microscopic examination during a dog's registration and the number of confirmed neoplasms derived from the submissions. Based on this index, 14.2% of additional tumors diagnosed in dogs already bearing at least one tumor could be attributed to a difference in the excess submission measure of diagnostic surveillance. This difference in diagnostic surveillance was constant over breed, sex, and tumor type.

Serologic enzyme-linked immunosorbent assay responses of calves vaccinated with a killed Mycobacterium paratuberculosis vaccine.

The purpose of this study was to document the effect of calfhood vaccination for Mycobacterium paratuberculosis on a serologic ELISA. Fifteen calves vaccinated with a killed paratuberculosis vaccine and 5 unvaccinated control calves were tested from the first through the fifteenth month of life. Age of vaccination ranged from 5 to 40 days. Blood samples were collected prior to vaccination and periodically thereafter. Serum antibody was analyzed by use of the ELISA. All calves were ELISA-negative prior to vaccination. Thirteen of 15 vaccinated calves became ELISA-positive between 2 and 6 months after vaccination. The unvaccinated cohort remained ELISA-negative. Wide-spread use of vaccine may interfere with diagnosis of paratuberculosis and with control programs that are based on serologic tests that measure humoral antibody.

Characterization of Mycobacterium paratuberculosis antigenic proteins.

The characterization of a purified antigen from Mycobacterium paratuberculosis, recently made commercially available for use in serodiagnosis by enzyme-linked immunosorbent assay (ELISA), of paratuberculosis in cattle was described. This assay had 89% specificity and 83% sensitivity for M paratuberculosis infection. The protein/polypeptide composition of the purified antigen was compared with that of a crude protoplasmic extract of strain 18 M paratuberculosis used in the agar-gel immunodiffusion test and ELISA and with that of sonicated strain 19698 M paratuberculosis organisms grown on Dorset-Henley synthetic liquid medium. The sonicated M paratuberculosis contained 27 major proteins/polypeptides; the crude protoplasmic extract, 18; and the purified antigen contained 14 proteins/polypeptides, using sodium dodecyl-sulfate polyacrylamide-gel electrophoresis analysis. The serologic reactivity of these proteins/polypeptides were defined, using the enzyme-linked immuno-electrotransfer blot technique. The sonicated M paratuberculosis contained 20 serologically reactive proteins/polypeptides (34,000 to 84,000 daltons); the crude protoplasmic extract contained 3 (37,000 to 45,000 daltons); and the purified extract contained a diffuse polypeptide band (34,000 to 38,000 daltons). Identification by enzyme-linked immuno-electrotransfer blot technique of M paratuberculosis antigens reactive in the ELISA will allow us to further study these antigens in the ELISA to improve sensitivity and specificity of the diagnostic test.

Comparison of antibodies to Leptospira in white-tailed deer (Odocoileus virginianus) and cattle in Ohio.

A survey was conducted to determine the prevalence of leptospiral antibodies in sera from 248 white-tailed deer (Odocoileus virginianus) in Ohio. The sera were collected at check stations during the hunting season in 1983. The microscopic agglutination microtiter test was used to determine the presence of antibodies to Leptospira interrogans serovars pomona, icterohemorrhagiae, canicola, hardjo, and grippotyphosa. Eighteen of 248 (7.3%) serum samples had antibody titers (greater than or equal to 1:100) to at least one of the five serovars tested, with three of these samples reacting to more than one serovar. Prevalence did not differ significantly between sex or age groups. The serovar antigens reacting most frequently with serum antibodies were grippotyphosa (10 of 22, 45.5%) and pomona (eight of 22, 36.4%). Sera agglutinating with pomona antigen had higher titers (ranging from 1:200 to 1:6,400) than did sera agglutinating with the other serovars. These results were compared to results obtained from cattle tested at the Ohio Department of Agriculture Laboratories during 1983. There was a significant relationship between pomona infections detected in deer and cattle (P less than 0.05), but not with grippotyphosa.

Taenia saginata cysticercosis in an Ohio cattle feeding operation.

In January to March 1981, 37 slaughter cattle from a single Ohio feeding operation were determined, at postmortem inspection, to be infected with Taenia saginata cysticerci. A subsequent outbreak on this same farm in March 1983 involved 7 slaughter cattle. An epidemiologic investigation was conducted of possible sources of the T saginata ova; these included leakage of raw sewage onto the pasture after a flood in 1980, municipal sewage sludge application on the farm, defecation in feed or water by farm workers, and other off-farm sources. Temporal and spatial observations implicated raw sewage contamination of pastures as the most likely source of infection in the 1981 outbreak. The outbreak in 1983 was more likely associated with sludge application. The possibility of an infected worker exposing the cattle to infected feces was not excluded definitely as a possible source.

Epidemiologic analysis of oral and pharyngeal cancer in dogs, cats, horses, and cattle.

Four hundred sixty-nine oral-pharyngeal malignancies diagnosed in dogs, cats, horses, and cattle and submitted to the Viterinary Medical Data Program between March 1, 1964, and Dec 31, 1974, were analyzed. Of these cases, 84% were in dogs. The most frequent oral-pharyngeal cancer in dogs was melanoma; in cats and horses, it was squamous cell carcinoma. In dogs, the risk of developing melanoma increased more with age than did the risk of developing squamous cell carcinoma and fibrosarcoma. Male dogs had significantly greater risk of developing fibrosarcomas and melanomas than did female dogs. The German Shorthaired Pointer, Weimaraner, Golden Retriever, Boxer, and Cocker Spaniel breeds had significantly higher risk and Dachshunds and Beagles had significantly lower risk, as compared with all breeds combined. There was no significant difference between observed and expected numbers of tonsillar carcinomas diagnosed at veterinary colleges located in small urban areas (less than 50,000 persons) as compared with large urban populations (greater than 500,000).

Dog interaction with persons receiving institutional geriatric care.

A prospective study of 66 geriatric residents in 2 facilities was conducted to quantitate people-dog interactions. Residents were assigned randomly to sessions with dog activity and to sessions with other activity in a crossover design. This study involved a 12-week prestudy activity period and two 12-week activity periods, one before crossover and one after crossover. Systolic and diastolic blood pressures, psychologic evaluation of case histories, and other health and social variables were measured on all residents for dog activity and other combinations of programmed activity sessions. Frequence of attendance in both facilities was higher at dog activity sessions than at other activity sessions (P less than 0.01). Resident systolic blood pressures were lower in one facility during dog activity (P less than 0.02). Combined pre- and postactivity systolic and diastolic blood pressures at the same facility were lower when residents had 12 weeks of dog activity before 12 weeks of other activity (P less than 0.04). There were no significant differences in residents' blood pressures between measurements before and after dog activity (treatment mode) or between measurements before and after other activity. Psychologic scores of residents in both facilities were not significantly different between periods of the study. Of the 9 types of interaction between the residents and the dog, grooming and touching were the 2 most commonly used by residents.

Navicular disease in the horse: risk factors, radiographic changes, and response to therapy.

In a retrospective study, 74 horses met defined historical and clinical features indicative of navicular disease. Most of the affected horses were 4 to 9 years old. Males had a greater risk of navicular disease than females, geldings had a greater risk than stallions, and Quarter Horses had a greater risk than other breeds. Diagnostic radiographic changes were found in 42 of 70 horses examined. The distribution of diagnostic radiographic changes between the right and left fron feet was equal. There was no correlation between the finding of diagnostic radiographic changes and the horse's response to therapy or the type of work for which the horse had been used. A questionnaire regarding the current status of the horses in the study was mailed, and 51 replies were received. Of the 38 horses that were alive at least 6 months after treatment and for which the current status was known, 9 were sound at the time of follow-up (from 7 to 91 months after treatment). Three of these horses had been treated medically, 4 surgically, 1 by corrective shoeing, and 1 not treated. No advantage for medical or surgical therapy was demonstrated. The poor response to therapy in this group of horses suggests that the prognosis for horses with navicular disease should be guarded, and that the probability of a return to a prelameness capacity for work is slight.

Estimation of the costs of mastitis, using National Animal Health Monitoring System and milk somatic cell count data.

Data collected by the National Animal Health Monitoring System in Ohio for a 12-month period during 1986 and 1987 were used to determine the relative magnitude of costs associated with mastitis in the following categories: milk production loss, veterinary services, drugs, producer labor, and "other" factors. The cost of milk loss associated with mastitis that was reported by producers cooperating in the National Animal Health Monitoring System program was compared with estimates based on bulk tank somatic cell counts and individual cow milk somatic cell counts. Using producer-reported estimates, milk loss accounted for about one third of the total cost associated with mastitis. When estimates of milk loss were replaced by estimates based on bulk tank somatic cell counts, milk loss accounted for over 80% of the total cost of mastitis. Estimates of the cost of milk loss based on studies relating milk yield to somatic cell counts differed considerably. Consequently, it was unclear how to best estimate the relative magnitude of the milk loss component of mastitis costs.

Neutropenia and salmonellosis in hospitalized horses.

Colitis due to salmonellae was diagnosed in 9 horses following hospitalization for various reasons at the University of Missouri Veterinary Teaching Hospital, from May, 1971, to April, 1972. Diarrhea, fever, and either a neutrophil count of less than or equal to 3,600/cmm or a rapid decline in neutrophil numbers were specific for salmonellosis. The value of hematologic survelillance in hospitalized Equidae was demonstrated in another group of 9 horses with neutropenia, each of which was promptly treated and did not develop colitis. Bacteriologic culturing of fecal samples from 28 clinically normal horses yielded only 2 salmonella isolations, S manhattan in each case. The serotyped salmonellae isolated from the patients with colitis were all S typhimurium, with similar antibiotic resistance patterns.