Colostrum-deprived lambs (10 to 20 days old) were inoculated with either ovine adenovirus type 6 (OAV-6; n = 6), Pasteurella haemolytica type A1 (n = 6), or OAV-6 followed by P haemolytica 5 days later (n = 10). Another group (n = 3) served as sham-inoculated controls. Lambs inoculated with OAV-6 or P haemolytica developed mild and moderate respiratory tract disease of 6 and 3 days' duration, respectively. Lambs inoculated with virus and bacteria developed clinical signs of respiratory tract disease of greater intensity and duration (9 days) than with either agent alone. Within 3 hours of bacterial inoculation, all lambs that received P haemolytica were anorectic, listless, and febrile, and had hyperpnea and dyspnea. Ovine adenovirus type 6 was isolated from all virus-inoculated lambs. Although P haemolytica was not recovered from all bacteria-inoculated lambs, it was recovered for a longer period in the group that received both agents. Antibody to OAV-6 was detected in virus-inoculated lambs as early as day 6 after inoculation. The control lambs remained clinically normal and neither virus nor bacteria were recovered at necropsy.

A micro-ELISA, using horseradish peroxidase-conjugated anti-canine IgE and polystyrene microtitration wells for detection of allergen-specific IgE in canine serum, was developed. Specificity of anti-canine IgE was confirmed by reversed cutaneous anaphylaxis evaluations, gel-precipitation reactions, immunoelectrophoresis, immunoaffinity chromatography, and heat inactivation. Individual allergen blanks were used to account for variable nonspecific binding among various allergens, and results were normalized using 4 reference sera. Coefficients of variation for intra-assay and interassay variability ranged from 0.77 to 5.66% and 3.15 to 9.83%, respectively. Results observed with wells coated with mixtures of various allergen extracts yielded results approximately equal to results (average) of wells containing individual components. Agreement between ELISA and skin test results ranged from 43 to 64%, depending on allergen used.

Intraocular pressure (IOP) was determined in right eyes of 20 healthy dogs after sodium hyaluronate (1%, n = 5), sodium chondroitin sulfate (4%) and sodium hyaluronate (3%, n = 5), hydroxypropyl methylcellulose (2%, n = 5), or balanced salt solution (control, n = 5) was injected into the anterior chamber. Applanation tonometry was used to measure IOP in both eyes of each dog for up to 168 hours. The 3 viscoelastic solutions resulted in an increased mean IOP by postinjection hours (PIH) 2; from PIH 12 until PIH 72, the IOP was significantly (P less than 0.001) lower than baseline. The control group did not have an increase in IOP at PIH 2; mean IOP decreased below baseline measurements within 2 hours and remained lower until PIH 72. Mean differences in IOP were not found among treated eyes (P = 0.50), and a significant interaction of any treated eyes in a group was not detected (P = 0.21). By PIH 168, the IOP approached baseline values in all groups.

Four groups of 8 horses each had 1 midcarpal joint injected with 33 colony-forming units (CFU) of viable Staphylococcus aureus plus: 1 ml of saline solution (group 1, control), 250 mg of polysulfated glycosaminoglycan (PSGAG, group 2), 100 mg of methylprednisolone acetate (group 3), or 20 mg of sodium hyaulronate (group 4). Horses were euthanatized, and samples were obtained on the basis of clinical signs of septic arthritis that were nonresponsive to phenylbutazone administration. One group-1 horse, all 8 group-2 horses, 3 group-3 horses, and 4 group-horses 4 were culture-positive for S aureus and had clinical signs, results of synovial fluid analysis, and histopathologic findings that were consistent with sepsis. The addition of 250 mg of PSGAG increased the development of sepsis significantly (P = 0.001), compared with results in control horses. Differences in the development of sepsis between horses injected with methylprednisolone acetate or sodium hyaluronate and control horses were not significant.

Serum and vaginal Brucella-specific immunoglobulin isotypes (IgGl, IgG2, IgM, and IgA), obtained from 62 crossbred beef heifers vaccinated with Brucella abortus salt-extractable proteins and subsquently challenge exposed with B abortus S2308, were studied. Brucella-specific IgG antibodies and Brucella-specific immunoglobulin isotypes were quantitated by a fluorometric immunoassay. Serum and vaginal immunoglobulin responses were evaluated as a method of distinguishing infected from noninfected heifers. Rivanol precipitation, complement-fixation, buffered-antigen brucellosis tests and an ELISA were performed on sera. For immunoglobulin isotypes, vaccinated heifers had mean antibody responses higher than baseline mean antibody responses for at least 31 weeks after vaccination. After challenge exposure, significant differences (P > 0.05) were not detected between mean antibody responses of vaccinated and nonvaccinated heifers. Vaginal Brucella-specific antibody responses did not correlate with protection from disease. Vaginal Brucella-specific IgM was detected only at the time of abortion.

The effect of dry, soft moist, and canned dog foods on immediate postprandial plasma glucose and insulin concentrations was evaluated in clinically normal dogs. Dogs were fed either dry (10 dogs; group I), soft moist (10 dogs; group II), or canned (8 dogs; group III) dog food for 5 consecutive days. On the fifth day, plasma glucose and insulin concentrations were determined in each dog prior to, during, and at 5, 10, 15, 30, 45, 60, 90, 120, 180, and 240 minutes after ingestion of the food. The alterations in plasma glucose concentrations were not significantly different from prefeeding values until 240 and 180 minutes after feeding for groups I and III, respectively. In contrast, the increments in plasma glucose were significantly (P less than 0.01) increased from basal concentrations at 30 and 45 minutes after feeding in group-II dogs. The maximal mean postprandial plasma glucose concentration was significantly (P less than 0.0001) less for group III, compared with concentrations for groups I and II, but there was no significant difference between concentrations for groups I and II. Although a bisphasic insulin secretory response was found in all 3 groups of dogs, the patterns of phase-2 insulin secretion and the total amount of insulin secreted during the study were significantly different. There was a rapid increase in the plasma insulin concentration immediately after phase 1 in group II, with maximal plasma insulin concentrations occurring 30 minutes after feeding, followed by a gradual decrease in concentrations throughout the remainder of the study. In contrast, plasma insulin concentrations increased steadily in groups I and III, after phase-1 insulin secretion, with maximal values occurring at 240 minutes after feeding. The maximal mean increase from basal insulin concentrations during phase-2 secretion was significantly (P less than 0.005) greater for group II (80 +/- 15 micro IU/ml) than for groups I and III (23 +/- 3 and 24 +/- 6 micro IU/ml, respectively). Whereas the integrated areas under the glucose response curves were not significantly different between groups, total insulin secretion and total insulin secreted during phases 1 and 2 were significantly (P less than 0.01) greater in group II than in groups I and III. Differences in dietary composition may offer the best explanation for differences in postprandial glucose concentrations and insulin secretory responses between groups. These findings emphasize the importance of dietary formulations when designing hormonal studies or interpreting research data when dogs are the animal model.

Blood and urine chemical values at parturition in clinically normal Holstein cows (n = 12) were compared with the same values in Holstein cows developing udder edema (n = 12). There was no statistically significant mean difference between the 2 groups for the serum and urine chemical data. Furosemide (500 mg) given IV caused a significant increase in serum calcium and sodium, urine chloride, potassium, and sodium, and fractional excretional ratio of chloride, potassium, and sodium. There was a significant mean decrease in the serum potassium, urine creatinine, osmolality, pH, and specific gravity. Hydrochlorothiazide (250 mg) given IV caused a significant mean increase in serum chloride, urine chloride, potassium, and sodium, and fractional excretion ratio of chloride, potassium, and sodium. There was a significant mean decrease in serum potassium and sodium, urine osmolality, pH, and specific gravity. Acetazolamide (500 mg) given IV caused a significant mean increase in blood urea nitrogen, serum chloride and glucose, urine sodium, and fractional excretion ratio of sodium, while causing a significant mean decrease in serum potassium, sodium, and phosphorus, and urine creatinine. Dextrose (500 g) given IV as a 50% solution caused a statistical mean increase in serum glucose, urine chloride, potassium, and sodium, and fractional excretion ratio of chloride and potassium. A statistical mean decrease occurred in the packed cell volume, blood urea nitrogen, serum calcium, potassium, sodium, and phosphorus, urine creatinine, osmolality, and pH.

Interstitial fluid pressures, as a possible function of limb load, were measured at 2 sites within the digital coronary dermis of both cranial digits in 10 standing horses. Fluid pressure changes and digital load measurements were simultaneously detected and recorded by use of, respectively, modified wick-in-needle and force plate transducers coupled to a microcomputer. Mean pressures, recorded at limb loads between 50 and 80 kg, were 2.29 +/- 3.17 mm of Hg at the toe and 2.49 +/- 5.91 mm of Hg at the heel. Mean pressures, recorded between 150 and 180 kg, were 5.01 +/- 5.23 mm of Hg at the toe and 1.28 +/- 7.69 mm of Hg at the heel. These data indicate that, in the static limb, no statistically significant change in interstital fluid pressure occurs at loads up to 180 kg.

A transretinal method for recording the summed potentials generated by photoreceptors of the isolated canine retina in vitro is reported. Pieces from 10 retinas of 5 clinically and visually normal dogs were maintained in a recording chamber and superperfused with a modified cell culture medium. Sodium glutamate added to the medium eliminated electrical responses from retinal glia and allowed the summed receptor potentials to be recorded. The response to flashes of light consisted of a negative potential, which increased in amplitude in a graded manner and in complexity with increased stimulus intensity. The response was similar in waveform to that reported in other vertebrate species, using intracellular and extracellular techniques. This method of recording the mass transretinal receptor potentials in vitro will be of value for investigating abnormal photoreceptor functions in dogs in the early stages of inherited retinal degeneration.

Purified lipopolysaccharides (LPS) from 16 serotypes of Pasteurella multocida were complexed with Aspergillus fumigatus ribosomes. The complexes were used as inocula to prepare antisera, in chickens, for somatic antigen typing by the gel diffusion precipitin test (GDPT). Antisera made against 15 of 16 LPS reacted with their respective specific heat-stable antigens in the GDPT and homologous LPS in the passive hemagglutination test. Antisera could not be made against serotype 15 LPS. Correlation was not observed between intensity of the precipitin reaction in the GDPT and titer to homologous LPS in the passive hemagglutination test. Most antisera cross-related with other heat-stable antigens of other serotypes in the GDPT. Many of these cross-reactions were eliminated by dilution. Cross-reactions that occurred in the GDPT with antisera made against LPS of serotypes 2, 5, 7 and 8 could not be eliminated by dilution.