The prevalence of mycoplasmal and ureaplasmal recovery from tracheobronchial lavage specimens and prevalence of mycoplasmal recovery from pharyngeal swab specimens from cats with (28) or without (18) pulmonary disease were determined. Mycoplasmas were recovered from tracheobronchial lavage specimens in 21% of cats with pulmonary disease, but in no cats without pulmonary disease; this difference is significant (P = 0.04). Mycoplasmal recovery from tracheobronchial lavage specimens was not significantly associated with concurrent Pasteurella spp isolation, septic inflammation, or bronchitis. Ureaplasmas were only isolated from a tracheobronchial lavage specimen in cat with pulmonary disease and in no cats without pulmonary disease. Similar mycoplasmal recovery rates were found for pharyngeal swab specimens from cats with (39%) or without (35%) pulmonary disease. Seemingly, mycoplasmas are part of the normal pharyngeal flora in approximately a third of the feline population, but mycoplasmas are not normal inhabitants of the lower respiratory tract in cats. It is unknown whether mycoplasmas isolated from tracheobronchial lavage specimens in cats with pulmonary disease are primary pathogens or opportunistic invaders. Seemingly, ureaplasmas are seldom associated with pulmonary disease in cats, and are not normal inhabitants of the trachea and bronchi of cats.

Bacteroides nodosus isolates from 62 sources in the United States were obtained from sheep with infectious foot diseases. Serotypic analysis of these isolates revealed 21 serotypes (designated I-XXI). These serotypes were compared with British and Australian/New Zealand B nodosus strains by use of reciprocal tube agglutination tests. These tests, as well as the cross-matching tube agglutination tests of the US serotypes, resulted in arranging the US serotypes into 11 serogroups, and comparing these serogroups with their Australian/New Zealand serogroup and British serorype counterparts. Three US serogroups and 1 additional British serotype had little or no relationship to any of the Australian/New Zealand serogroups A-H (the vaccine strains). One or more of these unrelated serogroups were found in 29% of the sources studied. The most frequently found US serotype was serotype XV at 29%. The most frequently found US serogroups were the serogroups analogous to serogroup B (43.5%) and serogroup H (37%); the other serogroups were found in 22.6% or less of the sources studied. Evaluation of 3 sources revealed that multiple serotypes in a single flock are common, multiple serotypes from a single lesion are possible, B nodosus isolates obtained from goats (unlike those from cattle) appear identical to the isolates obtained from sheep, and disease can appear in vaccinated animals, even in a flock that appears to be harboring only a single serogroup-B serotype (the serogroup for which there are 3 strains in the current vaccine).

Immunoelectrophoresis and single radial immunodiffusion were used to identify and measure tear immunoglobulin concentrations in 50 healthy dogs. Immunoglobulin A and IgG were detected in all samples analyzed, whereas IgM was not detected in any sample. Mean IgA concentration was 25.28 +/- 1.9 mg/dl, adult dogs (> 18 months) having significantly higher mean value. The IgA concentration related to age had significant (P < 0.006) positive correlation; mean IgG concentration was 23.10 +/- 1.72 mg/dl. Linear correlation analysis revealed significant (P < 0.0007) correlation coefficient between tear total protein and IgA concentrations. The IgA and IgG concentrations also were significantly (P < 0.0001) correlated when expressed as milligrams per 100 mg of protein. Relation with sex was not established for either immunoglobulin.

The susceptibility of 50 clinical Escherichia coli isolates to various antibacterials, including cefoxitin and cefotetan was ascertained, and the minimal inhibitory concentration (MIC) of cefoxitin and cefotetan for each of these isolates was determined. The pharmacokinetics of cefoxitin and cefotetan after a single IV or SC injection (30 mg/kg of body weight) were determined in 4 dogs. Of the 50 E coli isolates, 98% were susceptible in vitro to cefotetan, 90% were susceptible to cefoxitin, and 88% were susceptible to gentamicin. The MIC that would inhibit the growth of 90% of the E coli isolates (MIC90) was 0.25 micrograms/ml for cefotetan and 4 micrograms/ml for cefoxitin. Plasma cefotetan concentrations remained above MIC90 for (mean SD) 8.2 +/- 1.72 hours and 13.52 +/- 0.28 hours after IV and SC administration, respectively. Plasma cefoxitin concentrations remained above MIC90 for (mean +/- SD) 5.37 +/- 1.18 hours and 7.95 +/- 0.71 hours after IV and SC administration, respectively. We concluded that cefotetan was superior to cefoxitin in activity against E coli in vitro. We recommend that cefotetan be given at a dosage of 30 mg/kg, IV, every 8 hours, or SC, every 12 hours.

Concentration of sulfamethazine was measured in plasma and tissues (fat, liver, kidney, spleen, lungs, and skeletal muscle) of pigs given the drug IV and PC. The plasma concentration vs time curve was best described by a 2-compartment model, with a distribution half-life of 0.46 hour and an elimination half-life of 16.9 hours. Bioavailability after oral administration was 85.8 +/- 5.3%. The tissue and plasma sulfamethazine concentration vs time data ,ere used to develop a multicompartment pharmacokinetic model of sulfamethazine disposition in pigs. Plasma and tissue concentrations of sulfamethazine in pigs were measured at various intervals after multiple oral doses of sulfamethazine, and were compared to concentrations predicted by the model. Model predictions for tissue concentrations of sulfamethazine after addition of the drug to feed (110 micrograms/g of feed for 98 days; 550 micrograms/g for 30 days) were compared to results from other studies. The model accurately predicted the number of days for sulfamethazine concentration to fall below 0.1 Kg of tissue/g (0.1 ppm. the tolerated concentration) in various tissues.

Microscopic examination of the nasal mucosa of clinically normal specific-pathogen-free pigs and of toxicogenic type-D Pasteurella multocida toxin challenge-exposed specific-pathogen-free pigs indicated that the surface epithelium in pigs of both groups was microscopically normal; erosions or appreciable inflammatory changes were not evident. In pigs of both groups and in aU 3 regions of the nasal cavity, the endothelial lining of all blood vessels appeared normal without detectable changes to the walls at postinoculation day 10. Vascular injury in the cartilage or the bone was not discernible in control or challenge-exposed pigs. There were marked differences in the osseous structures of the conchae when the 2 groups were compared. In control pigs, active bone formation and remodeling were observed, and the septal cartilage was normal. In toxin challenge-exposed pigs, there likewise was normal bone formation and remodeling in the vestibular region, and the septal cartilage was normal. In marked contrast, conspicuous changes were observed in the osseous core of the conchae of the respiratory and, sometimes, the olfactory regions. These changes consisted of bone necrosis and resorption by large numbers of osteoclasts with variable replacement by dense mesenchymal stroma, which resulted in conchal atrophy. In the absence of any discernible damage or injury (angiopathy) to the nasal vessels, it appears that the action of the dermonecrotoxin of P multocida serotype D is on the most active osteoblasts and the associated organic matrix of the bone, with subsequent disruption of normal bone formation and remodeling of the nasal conchae.

Streak retinoscopy was performed by 5 ophthalmologists on 256 eyes (191 dogs) to determine their postoperative refractive state after cataract extraction. Aphakic and pseudophakic eyes that had been implanted with 1 of 5 intraocular lenses (IOL) with dioptric powers ranging from +14.5 to +38 diopters (D) were studied. By use of ANOVA, breed and body type of dog and individual performing refraction were found to have no detectable effect on final refractive state. Mean refractive state of aphakic eyes was +14.4 +/- 2.10 D. Mean refractive state for different IOL powers was as follows: +14.5 D IOL = +11.54 +/- 1.18 D (n = 13); +30 D IOL = + 5.15 +/- 1.18 D (n = 105); +34.0 D IOL = +3.5 D (n = 1); +36 D IOL +2.34 +/- 0.73 D 9 (n = 61); and +38 D IOL = +1.41 +/- 0.56 D (n = 28). Residual hyperopia ranged from +0.5 D to +2.5 D with +38 D IOL, and no eyes were myopic (overcorrected) by use of any of the IOL studied. linear regression analysis of refractive state on IOL power for aU dogs predicted that dioptric strength of +41.53 D was necessary to best approximate emmetropia for the population as a whole. Body type of the dog had only slight effect (< 1.0 D) on predicted optimal IOL power. Further linear regression analysis of the 7 breeds studied predicted variations from +39.62 to +43.14 D in IOL powers necessary to approximate emmetropia. Results of the study support the routine use of canine IOL with dioptric strength of approximately +41.5 D in circumstances in which preoperative biometry and keratometry are not practical. The findings further suggest that, for the specific population of dogs studied, most of the dogs could be corrected to near emmetropia by use of a small range of IOL dioptric strengths, irrespective of body type or breed.

After a detailed anatomic study to determine puncture sites, 10 cadaver elbows from 5 dogs were examined arthroscopicalty to study the normal intraarticular anatomy, as viewed from the medial side. Subsequent dissection revealed absence of neurovascular injury and only minor iatrogenic damage to the cartilage. The technique was clinically applied and evaluated in 13 dogs (26 joints). The dogs recovered without complications. The technique proved to be safe and reliable for direct examination of nearly the entire joint. More specifically, it allowed systematic inspection of the medial and lateral humeral condyles, the medial and lateral coronoid processes, the caudal and middle parts of the head of the radius, the olecranon (including the anconeal process), and the medial collateral ligament.

The hemodynamic effects of 2 dosages of ephedrine were studied in 6 dogs anesthetized with isoflurane only (end-tidal concentration equivalent to 1.5 times minimum alveolar concentration). Following instrumentation, baseline (time 0) measurements included heart rate (HR), respiratory rate, mean arterial blood pressure (MAP), cardiac output, and blood gas tensions. Cardiac index (CI), stroke volume (SV), systemic vascular resistance (SVR), arterial oxygen content (CaO2), and oxygen delivery and consumption (DO2 and VO2, respectively) were calculated. Three dogs were given ephedrine IV at a dosage of 0.1 mg/ kg of body weight, and 3 dogs were given ephedrine IV at a dosage of 0.25 mg/kg. Measurements were recorded at 5, 10, 15, 30, and 60 minutes. Each dog then received the alternate dosage of ephedrine, and measurements were again recorded at the same intervals. Effects of ephedrine varied with dosage. Neither dosage was associated with significant changes in pH, PaO2, PaCO2, VO2, or respiratory rate. Ephedrine at a dosage of 0.1 mg/kg caused transient significant increases in MAP, CI, SV, CaO2, and DO2, significant decreases in HR and SVR, and a late, slight decrease in CaO2. Ephedrine at a dosage of 0.25 mg/kg caused a greater and more prolonged increase in MAP, as well as increases in CI, SV, and SVR, and a decrease in HR. The higher dosage of ephedrine also caused a pronounced increase in hemoglobin concentration and CaO2, resulting in a 20 to 35% increase in DO2 throughout the 60-minute experiment.

One hundred two dogs without known gastric lesions were evaluated to establish a reference range of gastric rugal fold thickness (millimeters). Mucosal folds were measureable for 63 examinations, and the length of the second lumbar vertebra was measured for 61 of the 63 (centimeters). Body weight was available in the case records of 29 dogs. Measurements of the mucosal folds were related to body weight (n = 29) and length of the second lumbar vertebra (n = 61) by use of linear regression analysis. Reference range of normal gastric mucosal fold thickness, 1 to 8 mm, was defined by this study for dogs of any breed weighing between 2 and 50 kg.