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  • Author or Editor: Larry J. Allen x
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SUMMARY

A surgical technique was developed for implanting a flexible polyurethane cannula in a lateral ventricle in the brain of calves. Initially, measurements were made on 25 calves at necropsy to develop equations for calculating coordinates for cannula placement. The distance (cm) caudal, in the sagittal plane, from the coronal suture line to the center of a hole to be drilled in the parietal bone of the skull was: 0.73 + (0.00925 × body weight [kg]). The distance (cm) lateral from the midline to the center of the hole to be drilled was: 0.018 + (0.6464 × distance caudal). The depth (cm) from the surface of the skull to the dorsal surface of the lateral ventricle was: 2.29 + (0.0159 × body weight [kg]). Surgery was subsequently performed on 17 calves. A 5-mm-diameter hole was drilled through the skull with a hand trephine at coordinates derived from the aforementioned regression equations. A polyurethane cannula (total length, 30 cm; 1 mm id; 2 mm od) covering a stainless-steel 20-gauge blunt-tipped needle (stylet) was lowered through the brain and into a lateral ventricle at an angle of 20.5° relative to the frontal bones of the skull. The blunt-tipped needle was then removed, and csf was allowed to drip from the cannula to verify placement. One stainless-steel screw was inserted 0.6 cm medial, and another was inserted 0.6 cm caudal to the hole in the skull. The area around the cannula, bone screws, and hole in the skull was covered with dental acrylic (approx 2 cm in diameter) to stabilize the cannula. With minimal restraint of calves, injection of substances into and withdrawal of csf from a lateral ventricle of the brain were possible in most calves for at least 6 weeks after surgery was performed.

Free access
in American Journal of Veterinary Research

Summary

To evaluate the efficacy of penicillin or penicillin and dexamethasone for treatment of infectious bovine keratoconjunctivitis, 6- to 8-month-old beef heifers with clinical signs of infectious bovine keratoconjunctivitis were randomly assigned to 1 of 3 treatment groups: penicillin only, penicillin and dexamethasone, or control. Cattle assigned to the penicillin group (n = 18) were treated with 3 daily subconjunctival injections of procaine penicillin G. Cattle assigned to the penicillin/ dexamethasone group (n = 13) were treated with 3 daily subconjunctival injections of procaine penicillin G and dexamethasone sodium phosphate. Control cattle (n = 14) were not treated. Healing times and frequency of recurrence for corneal ulcers; severity, diameter, and surface area measurements of corneal ulcers; and clinical scores did not differ among the 3 groups. Frequency of Moraxella bovis isolation from specimens of ocular secretions from ulcerated and nonulcerated eyes was similar in all groups. Minimum inhibitory concentration of penicillin G for 95 of the 102 tested M bovis isolates was 0.3 U/ml, and for 7 others was 0.03 U/ml. When first and last specimens from 42 of 45 calves with isolation of M bovis on serial microbial cultures were compared, the susceptibility of each last isolate was similar to that of the corresponding first isolate.

Free access
in Journal of the American Veterinary Medical Association

Objective

To evaluate alterations in lymphocyte subpopulations, CBC results, and clinical signs in neonatal calves inoculated with 3 commercially available proprietary multiple-antigen vaccines containing known quantities of endotoxin.

Design

Prospective, randomized controlled field trial.

Animals

36 healthy Holstein heifer calves between 3 and 31 days old.

Procedure

Vaccines were administered to 18 calves according to label instructions, except for the recommended age of administration. The 18 other calves served as unvaccinated controls. Two weeks after entry into the study, calves were given secondary doses of the same vaccines. Calves in both groups were examined and blood samples were collected for determination of lymphocyte subpopulations and hematological parameters once daily for 5 days beginning on the day that both the primary and the secondary vaccinations were given. Lymphocyte subpopulations, including BoCD2*, BoCD4+, BoCD8+, B cells, and γ/δ T cells, were determined by use of flow cytometry, using monoclonal antibodies as markers.

Results

Vaccinated calves did not develop clinical signs of illness. There were no significant differences in absolute numbers of lymphocyte subpopulations between vaccinated and unvaccinated calves. Vaccinated calves had significantly higher rectal temperatures, total WBC counts, and absolute neutrophil counts than did control calves. These differences persisted for 3 to 4 days after vaccination.

Clinical Implications

Findings confirm empirical observations that vaccination with multiple products at the same time may induce evidence of an inflammatory response in most calves. Additional research is indicated to further evaluate the safety of using multiple vaccines simultaneously. (J Am Vet Med Assoc 1996;209:638-642)

Free access
in Journal of the American Veterinary Medical Association