OBJECTIVE To determine the optimal anatomic site and directional aim of a penetrating captive bolt (PCB) for euthanasia of goats.
SAMPLE 8 skulls from horned and polled goat cadavers and 10 anesthetized horned and polled goats scheduled to be euthanized at the end of a teaching laboratory.
PROCEDURES Sagittal sections of cadaver skulls from 8 horned and polled goats were used to determine the ideal anatomic site and aiming of a PCB to maximize damage to the midbrain region of the brainstem for euthanasia. Anatomic sites for ideal placement and directional aiming were confirmed by use of 10 anesthetized horned and polled goats.
RESULTS Clinical observation and postmortem examination of the sagittal sections of skulls from the 10 anesthetized goats that were euthanized confirmed that perpendicular placement and firing of a PCB at the intersection of 2 lines, each drawn from the lateral canthus of 1 eye to the middle of the base of the opposite ear, resulted in consistent disruption of the midbrain and thalamus in all goats. Immediate cessation of breathing, followed by a loss of heartbeat in all 10 of the anesthetized goats, confirmed that use of this site consistently resulted in effective euthanasia.
CONCLUSIONS AND CLINICAL RELEVANCE Damage to the brainstem and key adjacent structures may be accomplished by firing a PCB perpendicular to the skull over the anatomic site identified at the intersection of 2 lines, each drawn from the lateral canthus of 1 eye to the middle of the base of the opposite ear.
To assess the extent of damage to the skull and brain of cadaveric dairy goat kids caused by a .22-caliber, 16-g pellet fired from a multipump air pistol at various power levels.
Cadavers of 8 male and 7 female dairy goat kids ≤ 5 days old.
Each cadaver was positioned in sternal recumbency with the head and neck extended on a straw bale. A multipump air pistol was held with the barrel perpendicular to and 2.5 cm from the head at the intersection of 2 imaginary lines that extended from the lateral canthus of each eye to the middle of the contralateral ear base and fired at half (5 pumps; n = 2), intermediate (7 pumps; 2), or full (10 pumps; 11) power. The head and neck were removed from the carcass for CT imaging and gross sectioning to determine the location of the pellet and extent of damage caused to the skull and brain.
The pellet successfully penetrated the skull of all 13 heads shot at full or intermediate power and 1 of the 2 heads shot at half power. The pellet did not fragment after entering the skull of any cadaver and penetrated the brainstem (necessary for instantaneous death) in only 7 cadavers.
CONCLUSIONS AND CLINICAL RELEVANCE
The described technique was insufficient for use as a stand-alone method for euthanizing young dairy goat kids. Modification of the technique warrants further research to determine whether air pistols can be used to effectively euthanize young goat kids.
During a large animal clinical rotation at the College of Veterinary Medicine, Iowa State University, veterinary students commented on observing variability in the route by which perioperative antimicrobials were being administered to prevent surgical site infections in cattle. The clinicians indicated that preoperative parenteral administration of antimicrobials was likely the preferred route, as suggested by the literature available on antimicrobial use in other veterinary species; however, such use results in drug residues that prevent immediate slaughter of the affected cattle for use in the food supply when surgical findings suggest a poor prognosis. Consequently, veterinarians are often under pressure
Objective—To compare efficacy of 2 commercial ovine Campylobacter vaccines and an experimental bacterin in guinea pigs following IP inoculation with Campylobacter jejuni IA3902.
Animals—51 female guinea pigs.
Procedures—Pregnant and nonpregnant animals were randomly assigned to 1 of 4 treatment groups and administered a commercial Campylobacter vaccine labeled for prevention of campylobacteriosis in sheep via two 5-mL doses 14 days apart (vaccine A; n = 13), another labeled for prevention of campylobacteriosis via two 2-mL doses (vaccine B; 12), an experimental bacterin prepared from the challenge strain (12), or a sham vaccine (14). Ten days later, animals were challenged IP with C jejuni IA3902; 48 hours later, animals were euthanized, complete necropsy was performed, and blood and tissue samples were obtained for bacteriologic culture.
Results—Administration of vaccine B or the experimental bacterin, but not vaccine A, significantly reduced 48-hour infection rates versus administration of the sham vaccine. A significantly reduced 48-hour infection rate was associated with administration of vaccine B independent of pregnancy status.
Conclusions and Clinical Relevance—Administration of vaccine B significantly reduced infection in guinea pigs challenged with C jejuni IA3902, similar to a homologous bacterin. Results suggested that vaccine B or an autogenous product may be effective in controlling ovine campylobacteriosis caused by this emergent abortifacient strain. Bacteriologic culture of blood, liver, bile, and uterus in nonpregnant guinea pigs 48 hours after inoculation may be a useful screening tool for comparing efficacy of C jejuni vaccines.
Objective—To compare pathogenicity of an emergent abortifacient Campylobacter jejuni (IA 3902) with that of reference strains after oral inoculation in pregnant guinea pigs.
Animals—58 pregnant guinea pigs.
Procedures—12 animals were challenged IP with C jejuni IA 3902 along with 5 sham-inoculated control animals to confirm abortifacient potential. Once pathogenicity was confirmed, challenge via oral inoculation was performed whereby 12 guinea pigs received IA 3902, 12 received C jejuni isolated from ovine feces (OF48), 12 received a fully sequenced human C jejuni isolate (NCTC 11168), and 5 were sham-inoculated control animals. After abortions, guinea pigs were euthanized; samples were collected for microbial culture, histologic examination, and immunohistochemical analysis.
Results—C jejuni IA 3902 induced abortion in all 12 animals following IP inoculation and 6 of 10 animals challenged orally. All 3 isolates colonized the intestines after oral inoculation, but only IA 3902 induced abortion. Evidence of infection existed for both IA 3902 and NCTC 11168; however, C jejuni was only recovered from fetoplacental units of animals inoculated with IA 3902. Immunohistochemical analysis localized C jejuni IA 3902 infection to subplacental trophoblasts, perivascular tissues, and phagocytes in the placental transitional zone.
Conclusions and Clinical Relevance—This study revealed that C jejuni IA 3902 was a unique, highly abortifacient strain with the ability to colonize the intestines, induce systemic infection, and cause abortion because of its affinity for the fetoplacental unit. Guinea pigs could be effectively used in the study of septic abortion after oral inoculation with this Campylobacter strain.
To evaluate the efficacy of tulathromycin for prevention of abortion in pregnant ewes when administered within 24 hours after experimental inoculation with Campylobacter jejuni.
20 pregnant ewes between 72 and 92 days of gestation.
All ewes were inoculated with a field strain of C jejuni (8.5 × 108 to 10.6 × 108 CFUs, IV). Eighteen hours later, ewes received either tulathromycin (1.1 mL/45 kg [2.4 mg/kg], SC; n = 10) or sterile saline (0.9% NaCl) solution (1.1 mL/45 kg, SC; sham; 10). Ewes were euthanized immediately after observation of vaginal bleeding, abortion, or completion of a 21-day observation period. Necropsy was performed on all ewes, and tissue specimens were obtained for bacterial culture and histologic examination.
1 sham-treated ewe and 1 tulathromycin-treated ewe developed signs of severe endotoxemia and were euthanized within 24 hours after C jejuni inoculation. Seven sham-treated and 2 tulathromycin-treated ewes developed vaginal bleeding or aborted and were euthanized between 4 and 21 days after C jejuni inoculation. The proportion of tulathromycin-treated ewes that developed vaginal bleeding or aborted during the 21 days after C jejuni inoculation (2/9) was significantly less than that for the sham-treated ewes (7/9).
CONCLUSIONS AND CLINICAL RELEVANCE
Results suggested that administration of tulathromycin to pregnant ewes following exposure to C jejuni was effective in decreasing the number of C jejuni–induced abortions. Because of concerns regarding the development of macrolide resistance among Campylobacter strains, prophylactic use of tulathromycin in sheep is not recommended.
Objective—To measure antibody titers against
bovine coronavirus (BCV), determine frequency of
BCV in nasal swab specimens, and compare calves
treated for bovine respiratory tract disease (BRD)
between those given an intranasally administered
vaccine and control calves.
Design—Randomized clinical trial.
Animals—414 heifer calves.
Procedure—Intranasal BCV antigen concentration
and antibody titer against BCV were measured on
entry to a feedlot. Calves were randomly assigned to
receive 3.0 mL of a modified-live virus vaccine against
bovine enteric coronavirus and rotavirus or 3.0 mL of
saline (0.9% NaCl) solution. Calves were confined to
1 of 2 pens, depending on vaccination status, for a
minimum of 17 days of observation (range, 17 to 99).
Selection of calves for treatment of BRD and scoring
for severity of disease were done by veterinarians
unaware of treatment status.
Results—Intranasal BCV (125/407 [31%]) and serum
antibody titers ≥ 20 against BCV (246/396 [62%])
were identified in calves entering the feedlot.
Vaccination was associated with significant decrease
in risk of treatment for BRD; intranasal BCV on entry
to the feedlot was associated with increased risk of
treatment. Univariate analysis revealed that control
calves with intranasal BRD on entry to the feedlot and
those with antibody titer < 20 were significantly more
likely to be treated for BRD.
Conclusions and Clinical Relevance—These data
provide further evidence of an association between
BCV and respiratory tract disease in feedlot calves.
An intranasally administered vaccine appeared to
reduce risk of treatment for BRD. (J Am Vet Med
Recent state and federal legislative actions and current recommendations from the World Health Organization seem to suggest that, when it comes to antimicrobial stewardship, use of antimicrobials for prevention, control, or treatment of disease can be ranked in order of appropriateness, which in turn has led, in some instances, to attempts to limit or specifically oppose the routine use of medically important antimicrobials for prevention of disease. In contrast, the AVMA Committee on Antimicrobials believes that attempts to evaluate the degree of antimicrobial stewardship on the basis of therapeutic intent are misguided and that use of antimicrobials for prevention, control, or treatment of disease may comply with the principles of antimicrobial stewardship. It is important that veterinarians and animal caretakers are clear about the reason they may be administering antimicrobials to animals in their care. Concise definitions of prevention, control, and treatment of individuals and populations are necessary to avoid confusion and to help veterinarians clearly communicate their intentions when prescribing or recommending antimicrobial use.
Viewpoint articles represent the opinions of the authors and do not represent AVMA endorsement of such statements.
Antimicrobial stewardship has been defined for the veterinary profession as “the actions veterinarians take individually and as a profession to preserve the effectiveness and availability of antimicrobial drugs through conscientious oversight and responsible medical decision-making while safeguarding animal, public, and environmental health.”1 These actions may include making a commitment in one’s veterinary practice by assigning a staff member to track stewardship activities, selecting antimicrobials in a judicious and evidence-based manner, or attending continuing education about antimicrobial use (AMU) decision-making. The