PROCEDURES Three 5F angiographic catheters of the same length (100 cm) and diameter (0.17 cm) but differing in curvature at the tip were labeled A (straight tip), B (tip bent in 1 place), and C (tip bent in 2 places). During a single anesthetic episode, attempts were made to blindly pass each catheter into the urinary bladder of each goat. Order of catheters used was randomized, and the veterinarian passing the catheter was blinded as to catheter identity. The total number of attempts at catheter passage and the total number of successful attempts were recorded.
RESULTS Catheter A was unsuccessfully passed in all 12 goats, catheter B was successfully passed in 8 goats, and catheter C was successfully passed in 4 goats. The success rate for catheter B was significantly greater than that for catheter A; however, no significant difference was identified between catheters B and C or catheters A and C.
CONCLUSIONS AND CLINICAL RELEVANCE 2 angiographic catheters were identified that could be successfully, blindly advanced in a retrograde direction into the urinary bladder of healthy sexually intact male goats. Such catheters may be useful for determining urethral patency, emptying the urinary bladder, and instilling chemolysing agents in goats with clinical obstructive urolithiasis.
Objective—To determine the pharmacokinetics of gallium maltolate (GaM) after intragastric administration in adult horses.
Animals—6 adult horses.
Procedures—Feed was withheld for 12 hours prior to intragastric administration of GaM (20 mg/kg). A single dose of GaM was administered to each horse via a nasogastric tube (time 0). Blood samples were collected at various time points from 0 to 120 hours. Serum was used to determine gallium concentrations by use of inductively coupled plasma-mass spectroscopy. Noncompartmental and compartmental analyses of serum gallium concentrations were performed. Pharmacokinetic models were selected on the basis of the Akaike information criterion and visual analysis of plots of residuals.
Results—Serum concentration data for 1 horse were such that this horse was considered an outlier and excluded from noncompartmental and compartmental analyses. Noncompartmental analysis was used to determine individual pharmacokinetic parameters. A 1-compartment model with first-order input and output and lag time was selected as the best-fit model for the data and used to determine mean — SD values for maximum observed serum concentration (0.28 — 0.09 μg/mL), time of maximum concentration (3.09 — 0.43 hours), time to the first measurable concentration (0.26 — 0.11 hours), apparent elimination half-life (48.82 — 5.63 hours), area under the time-concentration curve (20.68 — 757 h—μg/mL), and apparent volume of distribution (73,493 — 18,899 mL/kg).
Conclusion and Clinical Relevance—Further studies are necessary to determine the bioavailability of GaM after intragastric administration in adult horses.
Objective—To determine the pharmacokinetics of gallium maltolate (GaM) after intragastric administration in healthy foals.
Animals—6 healthy neonatal foals.
Procedures—Each foal received GaM (20 mg/kg) by intragastric administration. Blood samples were obtained before (time 0) and at 0.25, 0.5, 1, 2, 4, 8, 12, 24, 36, and 48 hours after GaM administration for determination of serum gallium concentrations by use of inductively coupled plasma mass spectroscopy.
Results—Mean ± SD pharmacokinetic variables were as follows: peak serum gallium concentration, 1,079 ± 311 ng/mL; time to peak serum concentration, 4.3 ± 2.0 hours; area under the serum concentration versus time curve, 40,215 ± 8,420 ng/mL/h; mean residence time, 39.5 ± 17.2 hours; area under the moment curve, 1,636,554 ± 931,458 ng([h]2/mL); and terminal half-life, 26.6 ± 11.6 hours. The mean serum concentration of gallium at 12 hours was 756 ± 195 ng/mL.
Conclusions and Clinical Relevance—Gallium maltolate administered via nasogastric tube at a dose of 20 mg/kg to neonatal foals resulted in gallium serum concentrations considered sufficient to suppress growth or kill Rhodococcus equi in macrophages and other infected tissues.
Objective—To determine efficacy of a modified-live virus (MLV) vaccine containing bovine viral diarrhea virus (BVDV) 1a and 2a against fetal infection in heifers exposed to cattle persistently infected (PI) with BVDV subtype 1 b.
Animals—50 heifers and their fetuses.
Procedures—Susceptible heifers received a placebo vaccine administered IM or a vaccine containing MLV strains of BVDV1a and BVDV2a administered IM or SC. On day 124 (64 to 89 days of gestation), 50 pregnant heifers (20 vaccinated SC, 20 vaccinated IM, and 10 control heifers) were challenge exposed to 8 PI cattle. On days 207 to 209, fetuses were recovered from heifers and used for testing.
Results—2 control heifers aborted following challenge exposure; both fetuses were unavailable for testing. Eleven fetuses (8 control heifers and 1 IM and 2 SC vaccinates) were positive for BVDV via virus isolation (VI) and for BVDV antigen via immunohistochemical analysis in multiple tissues. Two additional fetuses from IM vaccinates were considered exposed to BVDV (one was seropositive for BVDV and the second was positive via VI in fetal tissues). A third fetus in the SC vaccinates was positive for BVDV via VI from serum alone. Vaccination against BVDV provided fetal protection in IM vaccinated (17/20) and SC vaccinated (17/20) heifers, but all control heifers (10/10) were considered infected.
Conclusions and Clinical Relevance—1 dose of a BVDV1a and 2a MLV vaccine administered SC or IM prior to breeding helped protect against fetal infection in pregnant heifers exposed to cattle PI with BVDV1b.