Seven monoclonal antibodies (MAB) generated against sporozoites of Eimeria bovis were tested for reactivity against immature and mature first-generation meronts, sexual stages, and oocysts in tissues from experimentally infected calves by use of an avidin-biotin peroxidase complex (ABPC) immunohistologic test. Three of the 7 MAB reacted in the ABPC test. One of these, MAB-4FB4, reacted only with mature E bovis meronts. The other 2 MAB, MAB2AE7 and MAB4AD7, reacted with all the developmental stages of E bovis tested. Asexual stages and sexual stages of E tenella from chickens and E papillata from mice also were examined in the ABPC test. Monoclonal antibodies MAB-2AE7 and MAB-4AD7 reacted with all stages of these eimerian protozoa. None of the other 5 MAB reacted with these parasites. Results of this study suggested that antigens are shared among the asexual and sexual stages of several diverse Eimeria species.

Effects of topical administration of a single dose of timolol maleate, a nonselective beta-adrenergic blocking agent, on intraocular pressure (IOP) and pupil diameter were evaluated in the normotensive eyes of 10 clinically normal cats over 12 hours. Mean (+/- SEM) normal IOP was 17.1 (+/- 1.1) mm of Hg and diurnal fluctuation was observed, with the highest IOP seen in the evening. Mean (+/- SEM) normal pupil diameter was 10.1 (+/- 0.5) mm. Topical treatment with 0.5% timolol resulted in reduction of IOP in treated and nontreated eyes. This effect was time-dependent and was first observed at 6 hours after treatment. Mean reduction of IOP was 22.3% in the treated eye and 16.3% in the nontreated eye. The treated eye had reduced pupil diameter at 30 minutes after treatment, and miosis persisted throughout the 12 hours of the study. Mean reduction of pupil diameter was 38.7%. A contralateral effect on pupil diameter was not seen in the nontreated eye. Topical administration of timolol maleate results in a reduction of IOP in treated and contralateral eyes, which supports the use of timolol for treatment of glaucoma in cats. In addition, the treated eye becomes miotic. This effect may indicate beta-adrenergic inhibition or alpha-adrenergic activation of the iris sphincter muscle. beta-Adrenergic blockade would then result in miosis.

An ammonium sulfate-soluble fraction of Taenia hydatigena cyst fluid (ThFAS) was further evaluated for use in the immunodiagnosis of cysticercosis. Analysis of ThFAS by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and protein immunoblot analysis confirmed earlier reports of a highly specific, low molecular weight antigen in this preparation; in contrast, other components of ThFAS were shown to react nonspecifically. Antibodies against the < 12-kD diagnostic antigen were detected in sera from 10 cattle and 4 swine inoculated with metacestodes of T saginata and T solium, respectively, but not in animals inoculated with Fasciola hepatica, Trichinella spiralis, Brucella abortus, or Toxoplasma gondii, or in noninoculated controls. Isolation and immobilization of the < 12-kD antigen on a hydrophobic transfer membrane resulted in development of an unambiguous dipstick assay capable of correctly identifying fully developed (10-week) experimentally induced infections in cattle and swine. In addition, the dipstick assay was highly specific for diagnosis of the disease in human beings, and offers the potential of distinguishing between human clinical cases of cysticercosis and taeniasis. A similar reactive antigen of diagnostic potential was also identified and isolated from T crassiceps and T taeniaeformis cyst fluids.

Pili from 11 distinct serotypes of Bacteroides nodosus were examined for diversity of pilin polypeptide subunits among serotypes and for purity of the pilin preparations. The pilin of all 11 samples was shown to be homogeneous. Mean +/- SD molecular weight of the pilin of 7 serotypes (A198, IV, V, VI, IX, XVII, and XVIII) was 18,500 +/- 100. The pilin of serotypes I, III, and VIII had molecular weight of 17,600, 19,400, and 19,000, respectively. Serotype XV differed greatly from the other 10 serotypes in that 2 distinct polypeptide bands with molecular weight of approximately 7,800 and 6,200 were detected. We suggest that these 2 low molecular weight bands resulted from proteolytic cleavage of the pilin protein.

The pharmacokinetic properties of the fluoroquinolone antimicrobial enrofloxacin were studied in New Zealand White rabbits. Four rabbits were each given enrofloxacin as a single 5 mg/kg of body weight dosage by IV, SC, and oral routes over 4 weeks. Serum antimicrobial concentrations were determined for 24 hours after dosing. Compartmental modeling of the IV administration indicated that a 2-compartment open model best described the disposition of enrofloxacin in rabbits. Serum enrofloxacin concentrations after sc and oral dosing were best described by a 1- and 2-compartment model, respectively. Overall elimination half-lives for IV, SC, and oral routes of administration were 2.5, 1.71, and 2.41 hours, respectively. The half-life of absorption for oral dosing was 26 times the half-life of absorption after sc dosing (7.73 hours vs 0.3 hour). The observed time to maximal serum concentration was 0.9 hour after sc dosing and 2.3 hours after oral administration. The observed serum concentrations at these times were 2.07 and 0.452 microgram/ml, respectively. Mean residence times were 1.55 hours for IV injections, 1.46 hours for sc dosing, and 8.46 hours for oral administration. Enrofloxacin was widely distributed in the rabbit as suggested by the volume of distribution value of 2.12 L/kg calculated from the IV study. The volume of distribution at steady-state was estimated at 0.93 L/kg. Compared with IV administration, bioavailability was 77% after sc dosing and 61% for gastrointestinal absorption. Estimates of predicted average steady-state serum concentrations were 0.359, 0.254, and 0.226 microgram/ml for IV, sc, and oral administration, respectively. On the basis of maintaining enrofloxacin serum concentrations at 4 times the minimal inhibitory concentration for Pasteurella multocida, oral dosing resulted in the longest maximal time interval between doses of 15.4 hours vs 9.9 hours and 7.4 hours for IV and SC injections, respectively. Because enrofloxacin is widely dispersed in the rabbit's body, it is estimated from the data in this study that in vivo inhibitory concentrations of enrofloxacin for Pasteurella multocida may be maintained at oral dosage regimens equivalent to 5 mg/kg (q 12 h).

Butorphanol (0.025, 0.05, 0.1, 0.2, 0.4, and 0.8 mg/kg of body weight, and placebo) was given sc to 8 healthy unmedicated dogs to determine its efficacy for visceral analgesia, using a colonic balloon for minimal threshold nociceptor stimulation. Degree of sedation; systolic, diastolic, and mean arterial pressure; and pulse rate were recorded. The highest 3 dosages, 0.2, 0.4, and 0.8 mg/kg, were found to be most effective, with 0.8 mg/kg the only dosage that was significantly different from control responses at the 45-minute interval. Duration of analgesia ranged from 23 to 53 minutes for all 6 dosages and dosing durations were not significantly different from one another. Blood pressures did not change, but pulse rate was significantly decreased by 0.8 mg of butorphanol/kg. We concluded that butorphanol is an effective visceral analgesic of relatively short duration in the dog.

Sheets of mucosa from the jejunum of healthy horses were mounted in incubation chambers and bathed with Krebs-ringer bicarbonate solution. Changes in tissue function and histologic appearance were compared after the following conditions: (1) control conditions for 30 minutes with 95% O2/5% CO2 in the gas phase; (2) same conditions as control, except incubation with superoxide dismutase (300 U/ml) during the last 18 minutes; (3) anoxia for 15 minutes with 95% N2/5% CO2, followed by reoxygenation for 15 minutes; (4) same conditions as 3, except incubation with superoxide dismutase during reoxygenation; and (5) anoxia for 30 minutes. Anoxia reduced the accumulation of radiolabeled L-alanine and caused cell swelling, as indicated by an increase in tissue water and tissue Na contents. Reoxygenation improved the tissue's ability to accumulate L-alanine, but tissue swelling continued after this treatment. Tissue Na content and L-alanine accumulation were restored to control values by reoxygenation with superoxide dismutase in the bathing medium. The grade of structural damage, as indicated by separation of eptihelial cells from villi, was equally severe after all, but control, conditions. Superoxide dismutase had no effect on the tissue control conditions. Results of this study suggest that superoxide radicals are involved in the pathogenesis of reperfusion injury in equine jejunal mucosa and that this may be of clinical importance in cases of small intestinal strangulation obstruction.

An indexing system for hygiene variables associated with egg production was developed by use of datacollected from chicken flocks in southern California. The data were analyzed by factor and regression analysis. On the basis of our findings, hygiene index in relation to egg production consists of ventilation system, cooling system, manure removal, and truck movement. Flocks kept under natural ventilation produced, on the average, 2% more hen-day eggs than flocks kept under artificial ventilation. Flocks placed in houses with roof sprinklers produced 3.3% more hen-day eggs, compared with flocks placed in houses with inside foggers and pad. Flocks kept under the system of frequent removal of manure produced 2% more hen-day eggs than flocks kept under the system for which the manure was removed less frequently. Flocks kept in farms that restricted trucks collecting dead birds from entering the premises produced 3.4% more hen-day eggs than those that allowed such trucks to enter the farm.

Twenty-four specific-pathogen-free Beagles were each given 50 cysticerci of Taenia pisiformis that had been harvested from experimentally infected rabbits. Quantitative fecal egg counts and fecal screening for recovery of passed segments were performed on postinoculation days 56 through 70. Twenty-three of 24 dogs fed cysticerci developed patent infections. The 23 dogs with patent infections were assigned to 1 of 2 groups and treated with nitroscanate or a placebo 60 days after inoculation. Egg counts in the treated dogs had markedly decreased by the second day after treatment, and by the sixth day after treatment, segments were not found in the feces of any of the treated animals. The control dogs continued to pass eggs and segments in their feces throughout the 9 days after treatment. The dogs were euthanatized and necropsied 70 days after being inoculated. At necropsy, the mean number of scolices recovered from control dogs was 24.6, the mean number of scolices recovered from treated dogs was 0.25. Worms recovered from the control dogs were intact, gravid cestodes. Efficacy of treatment with nitroscanate at a mean dosage of 56 mg/kg of body weight was 98.9%.

Two commercially available synthetic adjuvant systems, trehalose dimycolate (TDM) and TDM + monophosphoryl lipid A (MPL), were compared with Freund complete adjuvant (FCA) for the ability to stimulate antibody production in New Zealand White rabbits (Oryctolagus cuniculus). In addition, each animal was evaluated for adverse reactions. The antigen, rat liver microsomal epoxide hydrolase, was administered sc emulsified with FCA, TDM, or TDM + MPL. Serum antibody titers were stimulated with all 3 adjuvant-antigen combinations. The highest titer was produced by use of FCA; TDM + MPL produced an intermediate response, and TDM produced the lowest titer. All of the rabbits immunized with FCA developed sterile subcutaneous abscesses. Rabbits immunized with TDM or TDM + MPL developed no abscesses, and only slight reactions at the injection sites. The synthetic adjuvant system TDM + MPL is recommended for use in rabbits, considering its adequate stimulation of antibody production with minimal adverse reactions.