Static lung compliance, static lung volumes, and transfer factor for carbon monoxide were measured in 12 anesthetized adult Texel ewes seropositive for maedi-visna virus (MVV) and in 11 breed-, sex-, and age-matched seronegative controls. Median static lung compliance in MVV-infected sheep (1.24 L.kPa-1; range, 0.27 to 2,20 L.kPa-1) was not significantly different from that in controls (1.58 L.kPa-1; range, 0.82 to 2.08 L.kPa-1). Median body weight of MVV-infected sheep (56 kg; range, 40 to 75 kg) was significantly (P < 0.05) less than that of controls (65 kg; range, 53 to 87 kg). Median effective alveolar lung volume in MVV-infected sheep (3.36 L; range, 1.44 to 4.52 L) was significantly (P < 0.01) less than that in controls (4.12 L; range, 3.75 to 4.90 L). Median effective end expiratory lung volume in MVV-infected sheep (1.20 L; range, 0.56 to 1.99 L) was significantly (P < 0.001) less than that of controls (1.98 L; range: 1.76 to 2.78 L). Median lung volumes expressed per unit of body weight did not differ significantly between the groups. Median single-breath transfer factor for carbon monoxide in MVV-infected sheep (7.89 mmol-min-1.kPa-1; range, 3.45 to 12.74 mmol.min-1.kPa-1) was significantly (P < 0.001) less than that in controls (14.10 mmol.min-1-kPa-1; range, 10.02 to 18.30 mmol.min-1-kPa-1). Median transfer factor expressed per liter of alveolar volume in MVV-infected sheep (2.44 mmol.min-1-kPa-1.L-1; range, 1.28 to 3.72 mmol.min-1-kPa-1.L-1) gm significantly (P < 0.05) less than that in controls (3.22 mmol.min-1-kPa-1.L-1; range, 2.47 to 3.74 mmol.min-1-kPa-1.L-1). These findings indicate that static lung volumes and transfer factor for carbon monoxide are significantly decreased in adult sheep naturally infected with MVV.

The popular urodynamic technique of stressed urethral pressure profilometry used for investigation of genuine stress incontinence in women was adapted and applied to bitches. The aim was to assess the suitability and reproducibility of the technique in the canine species, and to determine whether differences seen in continent and incontinent women were found in bitches. Resting and stressed simultaneous urethral pressure profiles were obtained for 25 continent and 25 incontinent bitches, the latter diagnosed as having urethral sphincter mechanism incompetence. The stressed urethral pressure profiles were produced by ballottement of the abdomen during catheter withdrawal. The degree of stress induced was consistent and had got short-term reproducibility. Highly significant (P < 0.001) differences in the percentage of negative spikes extending below the resting intravesical pressure were found between continent and incontinent bitches. Significant differences were not observed in the pressure transmission profiles between continent and incontinent bitches; both groups had a gradual decrease in pressure transmission from the bladder neck to the external urethral orifice. The distance from the start of the urethral pressure profile to the first negative peak (attributable to respiration or ballottement) on the subtracted profile was compared with the radiographic distance that the bladder neck was positioned with respect to the cranial pubic brim, taking body weight and continence status into account. Body weight and continence status did not have significant effect on the relation in either instance. The distance between the start of the urethral pressure profile and the first negative peak induced by respiration was significantly (P < 0.05) related to the bladder neck position with respect to the cranial pubic brim, although it accounted for little of the total variance. Relation between the same variables during stressed urethral pressure profilometry, induced by abdominal ballottement, was not significant.

Pili have been implicated as virulence factors that result in increased infectivity of Moraxella bovis, the causative agent of infectious bovine keratoconjunctivitis (IBK). Healthy calves' eyes were inoculated with I- or Q-piliate or nonpiliate M bovis Epp63 to compare the pathogenicity of these isogenic variants. Pathogenicity was determined by the rate of persistent M bovis infection and the prevalence of clinical IBK. Inoculation with M bovis expressing the Q pili resulted in the highest frequency of infection and IBK whereas I-piliate M bovis elicited a lower rate and nonpiliate M bovis did not result in infection. In vivo pilin gene rearrangement and pilin-type switching were evaluated by DNA hybridization and immunoblot. Gene rearrangement and type switching varied dependently, and were observed only in eyes inoculated with Q-piliate M bovis. This study suggests that Q pili are specific for colonization of bovine corneal epithelium, whereas I pili enable maintenance of an established infection.

Virulence of three Canadian poultry strains of Salmonella enteritidis, namely phagetypes (PT) 4, 8 and 13, and one Salmonella heidelberg strain was assessed in orally and intraperitoneally inoculated one-day old chickens and compared to the virulence of a human S. enteritidis PT 4 strain from the United Kingdom (UK). The two PT 4 strains were also compared in orally inoculated adult laying hens. In addition, orally inoculated Balb/c mice were used to evaluate virulence of the above strains and two strains of Salmonella typhimurium containing different plasmids. In orally inoculated one-day old chickens, the UK S. enteritidis PT 4 strain was more virulent than the Canadian PT 4 strain. The UK PT 4 strain was also more virulent and invasive in adult laying hens than the Canadian PT 4 strain. The S. enteritidis PT 8 strain and one S. typhimurium strain isolated from a chicken hatchery were the most virulent for orally inoculated Balb/c mice. This strain of S. typhimurium contained the 60 megadalton plasmid associated with virulence for Balb/c mice which was not present in the S. typhimurium strain isolated from a pig with septicemic disease.

The IgG and IgM classes of antibodies to a water-soluble antigen preparation derived from microsporum canis were determined by ELISA in the sera of 79 cats with dermatophytosis confirmed by results of fungal culture, and of 46 specific-pathogen-free-derived, barrier-maintained cats with no previous exposure to dermatophytes. Of the 79 cats with dermatophytosis, the species isolated were: M canis from 72, M gypseum from 6, and Trichophyton mentagrophytes from 1. Concentrations of soluble M canis antigen-specific IgG and IgM were significantly (P < 0.05) higher in the cats with dermatophytosis than in the control cats. The IgG concentration was larger than or equal to 2.0 ELISA units/ ml in 71% of the cats with dermatophytosis and in 9% of the control cats, whereas IgM concentration was greater than or equal to 4.0 ELISA units/ml in 38% of the cats with dermatophytosis and in 11% of control cats. There was no significant difference in either IgG or IgM values between the cats with M canis infection and those with other non-M canis dermatophyte infections.

Twelve mature (5 sexually intact males, 4 castrated males, and 3 females) mixed-breed dogs were surgically thyroidectomized and used in a Latin-square design pharmacokinetic study of orally administered L-thyroxine. The dogs were treated with 44, 22, and 11 Kg of L-thyroxine/kg as a single morning dose or in divided doses, morning and evening. Serum concentration of thyroxine (T4) was evaluated to determine a number of pharmacokinetic variables for comparison. Mean steady-state concentrations (C(SS)) were determined from the area under the curve. Variables were analyzed for comparisons between dosages by use of ANOVA. Concentration at steady state was highest for dogs of the 44-micrograms/kg of body weight once-daily group and was lowest for dogs of the group given 11 micrograms/kg in 2 daily doses. Single daily administration resulted in higher C(SS), except at the 22-micrograms/kg/d dosage. Clearance was faster for the 22- and 44-micrograms/kg/d dosages than for the 11-micrograms/kg/d dosage. The half-life (t(1/2)) and mean residence time (MRT) also were shorter for the 44-micrograms/kg/d dosage, possibly indicating more rapid elimination of the drug at higher doses and dose-dependent kinetics. Perhaps, as the dogs' metabolism increased with higher iodothyronine concentrations, hormone degradation was accelerated. Interval (divided vs single dose) caused some expected changes: maximal concentration was higher and minimal concentration was lower when single administration was used. These undulations resulted in iodothyronine concentrations above the physiologic range for a number of hours, whereas concentration closer to physiologic ranges was achieved by use of divided doses. Delayed absorption (lag time) was seen in 37 of the 72 data sets, but was generally short, about 0.25 hour. Mean time to maximal concentration was 3 to 4 hours. At the higher dosages, serum total T4 concentration was high normal or above normal during most of the time after L-thyroxine administration, but serum concentration of total 3,5,3'-triiodothyronine did not remain within the normal range until the 44-micrograms/kg/d dosage was used. The customary dosage of 22 micrograms/kg/d (0.1 mg/10 lb/d) may not be adequate for most dogs. Pharmacokinetic variables appear to be highly dependent on the individual dog. Those with rapid absorption and higher concentration tended to have these characteristics at each dosage in this study. The pharmacokinetic variables, therefore, appear to be highly individualized, and dosages recommended for treatment of hypothyroidism should be considered to be only a starting point for the average dog. To avoid underdosing or overdosing, monitoring of treatment to adjust dose for individual dog kinetic variables seems to be imperative.

Eight dogs were determined to be orthopedically normal on the basis of prelavage physical examination, stifle radiography, synovial fluid analysis, and force plate analysis (peak vertical force normalized for body weight, and time on the force plate). Each dog had 1 stifle randomly assigned to be lavaged with 100 ml of a commercially available 0.05% (w/v) chlorhexidine diacetate solution, and the contralateral stifle was lavaged with lactated Ringer's solution. Difference was not detected between the chlorhexidine diacetate and lactated Ringer's solution-treated joints, with regard to results of synovial fluid analysis and clinical lameness evaluations on days 4 and 8 after lavage. Chlorhexidine diacetate caused a more intense synovitis than did lactated Ringer's solution, as determined by histologic evaluation of synovial membrane specimens after necropsy on day 8; however, a difference in the intensity of toluidine blue staining of articular cartilage was not found between treatments. Chlorhexidine diacetate, as a 0.05% (w/v) solution, cannot be recommended as a joint lavage fluid until the duration of inflammatory changes in the synovial membrane are determined or until the chemical constituents of chlorhexidine diacetate causing the synovitis can be identified and removed.

A rebreathing method for measurement of pulmonary diffusing capacity for carbon monoxide (DL(CO)) and functional residual capacity (FRC) was evaluated in conscious horses. Horses were manually ventilated through an endotracheal tube, using a custom-made syringe filled with a gas mixture containing 18-carbon monoxide (18CO) and helium (He). The 18CO and He concentrations were continuously monitored by use of a mass spectrometer connected to the rebreathing circuit. Values for DL(CO), and FRC were calculated from changes in the concentration of these 2 gases. In 11 Thoroughbreds, mean (+/- SD) DL(CO) was 330.3 +/- 56.9 ml.min-1.mm of Hg-1, and FRC was 20.21 +/- 3.35 L. Body weight normalization yielded mean (+/- SD) values of 0.652 +/- 0.114 ml.min-1.mm of Hg-1.kg-1 for DL(CO), and 39.9 +/- 6.4 ml.kg-1 for FRC.

A six month-old sheep was entered into a control group in an experiment designed to study the effects of exposure to the bovine immunodeficiency-like virus (BIV). Anti-BIV antibodies were detected in the serum of this sheep prior to the start of the study; these antibodies persisted for 12 months at which time the animal was destroyed. The sheep was normal clinically and was grossly normal at postmortem examination. Blood from this sheep was inoculated into a recipient sheep which subsequently showed a transient anti-BIV antibody response beginning two months postinoculation. Sheep have been previously shown to produce anti-BIV antibodies after experimental inoculation with infected cell culture material or infected bovine blood and BIV infection was found in a sheep pastured with BIV-infected cattle. In the present case there was no contact with cattle; the source of the infection was not identified.

Corticocancellous bone graft was obtained from the caudoventral portion of the mandible of 8 dogs. The recipient site was an alveolar jugal and alveolar defect from vital root amputation of the mesiobuccal root of the maxillary fourth premolar. Anatomic observations of 20 canine cadavers indicated that guidelines for harvesting bone from the caudoventral portion of the mandible of dogs were the mesial aspect of the masseteric fossa, the distal aspect of the roots of the first mandibular molar, and the ventral aspect of the mandibular canal. The mean weight of corticocancellous bone harvested was 0.4 +/- 0.1 g. Harvested corticocancellous bone was adequate to fill recipient sites measuring a mean volume of 105.0 +/- 28.5 mm3. Histologic evaluation of the recipient site revealed progressive osseous integration of the bone. graft site during a mean follow-up period of 3.5 +/- 1.9 months. There was normal bone healing of the donor site without adverse effects on the mandibular molars or neurovascular structures of the mandibular canal. Vital amputation sites receiving silver amalgam had evidence of plasmacytic/lymphocytic inflammation associated with residual silver amalgam in the bone-graft area. The caudoventral portion of the mandible may be used as a donor site for autogenous corticocancellous bone in periodontal surgery of dogs.