Immunoassay of serum ferritin is currently used to evaluate the clinical iron status of human beings, horses, cattle, and swine. Because ferritins are immunologically species specific, a separate assay must be developed for each species. We have developed an ELISA for serum ferritin in dogs, using a monoclonal anti-canine ferritin antibody. Ferritin standards were linear (r = 0.997) from 0 to 80 ng/ml. Recovery of ferritin from canine serum was 94%. Dilutions of pooled canine serum were linear from 0 to 50% (r = 0.994). Within-assay coefficient of variability was 5.5%, whereas assay-to-assay coefficient of variability ranged from 12.5 to 21%. This assay should provide a nonsurgical means of accurately estimating dogs' iron stores.

Bovine fibroblast interferon (BoF-IFN), produced in primary bovine embryonic kidney cell cultures after priming and infection with bluetongue virus, was purified by controlled pore glass (CPG) chromatography to a specific activity of 10(6) U/mg of protein, with 40% recovery of the original activity. The crude IFN was concentrated more than sevenfold during purification. This proved to be a relatively simple, practical method of obtaining sufficient quantities of partially purified natural BoF-IFN for further studies. The CPG-purified BoF-IFN was further concentrated by sequential ultrafiltration and was analyzed by sodium dodecyl sulfate/polyacrylamide-gel electrophoresis (SDS-PAGE). Interferon, recovered from denaturing conditions either by dialysis against phosphate-buffered saline solution or by dilution in cell culture medium containing 10% fetal bovine serum, migrated as a single stainable protein with molecular weight of 21,000 on analytic SDS-PAGE gels. Recovered IFN activity from preparative SDS-PAGE totalled 8.7% of that applied. Attempts to further purify CPG-purified BoF-IFN by zinc chelate affinity chromatography were unsuccessful.

Adult Beagles were used to evaluate clinical signs and serologic response after inoculation with, or exposure to, Borrelia burgdorferi. An indirect immunofluorescent assay (IFA) and 2 ELISA were used to monitor the serologic response to B burgdorferi. Feeding infected ticks on 4 dogs (group 1) failed to cause seroconversion, and SC inoculation with 500 organisms caused minimal seroconversion in 2 of 4 dogs (group 2). At 56 days, approximately 3.01 X 10(8) B burgdorferi organisms were injected IV into group-1 dogs, and intraperitoneally into group-2 dogs. A control group of 4 dogs (group 3) had noninfected ticks feed on them, and then were given IV injection of physiologic saline solution. Increases in immunoglobulin M (IgM) titers were detected in 2 of 4 group-2 dogs approximately 7 days after the initial exposure. These titers returned to negligible values 20 days later. Immunoglobulin G titers increased approximately 10 days after the initial exposure and were mildly increased 56 days later, when dogs were exposed a second time. Both the IV and intraperitoneal injections (second exposures) resulted in increased IgM titers, which in both groups eventually returned to preexposure values after approximately 2 months. Immunoglobulin G titers increased within a week after the second exposure, and in 3 dogs monitored for 8 months, returned to negligible values after the 8-month period. One control dog had a slightly increased IgG titer 24 days after the second inoculation. The possibility of urine transmission is suggested. Clinical status, hemograms, serum biochemical profiles, ECG and results of urinalyses remained normal throughout the study. Borrelia burgdorferi was not isolated from either the blood or urine of these dogs. Gross or microscopic pathologic changes were not detected on necropsy.

Studies were conducted to ascertain in vitro effects and effects of percutaneous application (in vivo) of dichlorvos (2,2-dichlorovinyl dimethyl phosphate; DDVP) on cholinesterase activities in bovine erythrocytes and plasma. Treatment in vitro of erythrocytes and plasma with DDVP resulted in concentration- and time-dependent inhibition of erythrocyte acetylcholinesterase (AChE) and plasma cholinesterase (ChE) activities. Mean (+/- SD) DDVP concentrations required to cause 50% enzyme inhibition were 15.7 +/- 3.3 muM and 43.1 +/- 5.7 muM for AChE and ChE, respectively; however, these values required to achieve this inhibition were markedly decreased with increasing incubation time. The inhibited AChE activity failed to be reactivated after incubation of erythrocytes with 2-pyridine aldoxime methiodide (2-PAM); however, limited reactivation of inhibited AChE and ChE activities was observed with excess concentration of 2-PAM. Percutaneous application of a DDVP-containing livestock spray on cattle also caused a marked decrease in the in vivo activities of AChE and ChE; however, the inhibited enzyme activities were reactivated rapidly after incubation with 2-PAM.

Ureterocolonic anastomosis was evaluated in 13 clinically normal dogs. Urinary continence was maintained after surgery, and the procedure was completed without technique errors in all but 2 dogs. Three dogs died within 5 weeks (2 of undetermined causes and 1 of aspiration pneumonia and neurologic disease), and 1 dog was euthanatized 4 months after surgery because of neurologic signs. Two healthy dogs were euthanatized 3 months after surgery for light microscopic evaluation of their kidneys. Five dogs were euthanatized 6 months after surgery for light microscopic evaluation of their kidneys. Gastrointestinal and neurologic disturbances developed in 4 dogs at various postoperative intervals. Plasma ammonia concentration measured in 2 dogs with neurologic signs was increased. Plasma ammonia concentration measured in 5 dogs without neurologic signs was within normal limits. All 5 dogs, in which metabolic acidosis was diagnosed, had high normal or above normal serum chloride concentration. Serum urea nitrogen values were increased after surgery because of colonic absorption of urea. Serum creatinine concentration was increased in 1 dog 6 months after surgery. Individual kidney glomerular filtration rate was reduced in 38% (3/8) of the kidneys from 4 other dogs at 6 months after surgery. Of 5 dogs euthanatized at 3 to 4 months after surgery, 4 had bilateral pyelitis, and 1 had unilateral pyelonephritis. Six months after surgery, pyelonephritis was diagnosed in 40% (4/10) of the kidneys from 5 dogs. The ureterocolonic anastomosis procedure is a salvage procedure that should allow complete cystectomy. However, variable degress of metabolic acidosis, hyperammonemia, and neurologic disease may result.

Three Beagles with chronic anemia and reticulocytosis were studied. The dogs originated from a large breeding colony and appeared clinically normal with the exception of splenomegaly. The PCV ranged from 30 to 39% (normal, 46 to 56%), with reticulocyte indices of 2.3 to 9.9. Red blood cells were morphologically normal, and examination of marrow aspirates revealed erythroid hyperplasia. Shortened chromium-51 RBC life-spans (7.2 to 15.4 days in anemic dogs; 22.2 to 25.2 days in control dogs) documented a hemolytic anemia. Acquired causes of hemolytic anemia were ruled out. Red blood cells had normal glycolytic enzyme activities, no evidence of unstable or abnormal hemoglobin, and had altered osmotic fragility curves. The breeding of 2 anemic dogs resulted in off-spring with anemia and reticulocytosis. Polyacrylamide gel electrophoresis revealed no abnormalities in RBC membrane cytoskeletal proteins in all anemic adult dogs and in 3 offspring.