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Abstract

Objective—To investigate the effect of an Escherichia coli that produced microcin 24 (Mcc24) on shedding of Salmonella enterica serotype Typhimurium in swine and evaluate evidence of in vivo activation of the Mcc24-mediated, multiple-antibiotic resistance ( mar) operon.

Animals—36 crossbred weaned pigs.

Procedure—24 pigs were allocated to 2 groups (12 pigs/group). Pigs in 1 group received daily oral administration of an Mcc24-producing E coli, whereas the other group received a non–Mcc24-producing E coli. All pigs were challenge exposed with Salmonella Typhimurium χ4232. A third group of 6 pigs received Mcc24-producing E coli and was challenge exposed with an Mcc24-sensitive, marA-deleted strain of SalmonellaTyphimurium 4232. After challenge exposure, fecal samples from all pigs were cultured to detect shedding of Salmonella Typhimurium and Salmonella Typhimurium isolates were screened for resistance to ciprofloxacin. Fecal samples were collected throughout the study, and tissue samples were collected during necropsy.

Results—Differences in shedding of Salmonella Typhimurium were not detected between groups receiving Mcc24-producing or non–Mcc24-producing E coli. No significant differences were found in quantitative analysis between groups receiving Mcc24-producing and non–Mcc24-producing E coli. Evidence of maractivation was not detected.

Conclusions and Clinical Relevance—Microcin-producing E coli did not exert an effect on shedding of Salmonella Typhimurium or maractivation in pigs. It may be difficult or impractical to create the conditions required for Mcc24 to be an effective part of a food safety intervention to reduce shedding of Salmonella Typhimurium. (Am J Vet Res 2004;65:1616–1620)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To characterize rib, intrathoracic, and concurrent orthopedic injuries, and prognosis associated with traumatic rib fracture in cats.

Design—Retrospective study.

Animals—75 cats.

Procedure—Medical records from January 1980 to August 1998 were examined for cats with traumatic rib fracture. Signalment, cause of trauma, interval from trauma to evaluation at a veterinary teaching hospital, referral status and date, method of diagnosis, duration of hospitalization, number and location of rib fractures, presence of flail chest, costal cartilage involvement, intrathoracic and concurrent orthopedic injury, and clinical outcome were reviewed.

Results—Median age was 3 years. Twenty-five (58%) cats with reported cause of trauma were injured by interaction with another animal. Fortyseven (78%) cats that were treated survived. Cats that died had a median duration of hospitalization of < 1 day. Ten (13%) cats had flail chest. Sixty-five (87%) cats had intrathoracic injury (median, 2 injuries). Nine (100%) cats without detected intrathoracic injury that were treated survived. Thirty-five (47%) cats had concurrent orthopedic injury. Cats with flail chest, pleural effusion, or diaphragmatic hernia were significantly more likely to die than cats without each injury.

Conclusions and Clinical Relevance—Traumatic rib fracture in cats is associated with intrathoracic and concurrent orthopedic injury. Aggressive treatment of cats with traumatic rib fracture is warranted, because the prognosis is generally favorable. Diagnosis and treatment of intrathoracic injury associated with traumatic rib fracture in cats should precede management of concurrent orthopedic injury. ( J Am Vet Med Assoc 2000;216:51–54)

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To evaluate 2 doses of alfaxalone on cardiopulmonary parameters, temperature, sedation, endotracheal intubation, the incidence of muscle tremors, and radiographic positioning in Quaker parrots previously administered intranasal midazolam and butorphanol.

ANIMALS

10 healthy adult Quaker parrots (male = 5; female = 5).

PROCEDURES

A randomized, masked, crossover study was conducted where birds received midazolam (2 mg/kg) and butorphanol (2 mg/kg) intranasally 15 minutes prior to a low- or high-dose of intramuscular alfaxalone: 2 mg/kg (LDA) or 5 mg/kg (HDA), respectively. Heart (HR) and respiratory rate (RR), cloacal temperature, sedation quality, and ability to position for radiographs were recorded over time. The incidence of muscle tremors and the ability to intubate were recorded. Data were compared to baseline values and between treatments where appropriate. Significance was set at P < .05.

RESULTS

There were no significant differences in HR, RR, cloacal temperature, and sedation scores between treatments at any time point. Duration of time from midazolam-butorphanol administration to complete recovery from treatment administration was significantly shorter for LDA when compared to HDA (90 [60 to 195] vs 127.5 [90 to 10] minutes, respectively). Compared to baseline, sedation scores were significantly higher from T = 15 to 60 for LDA and from T = 15 to 75 for HDA. The incidence of muscle tremors was greater in HDA (9/10) than in LDA (7/10). All birds were successfully intubated and positioned for radiographs.

CLINICAL RELEVANCE

The combination of intranasal midazolam-butorphanol and intramuscular alfaxalone at the doses examined was a safe and effective method for sedating Quaker parrots. LDA produced adequate sedation with a shorter time to recovery and with fewer muscle fasciculations when compared to HDA.

Open access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To compare intraocular pressures (IOPs) estimated by rebound and applanation tonometry for dogs with lens instability.

ANIMALS

66 dogs.

PROCEDURES

Medical records of dogs examined between September 2012 and July 2018 were reviewed for diagnoses of anterior (ALL) or posterior (PLL) lens luxation or lens subluxation.

RESULTS

Estimates of IOP obtained with rebound and applanation tonometry significantly differed from each other for all types of lens instability considered collectively (mean ± SE difference between tonometric readings, 8.1 ± 1.3 mm Hg) and specific types of lens instability considered individually (mean ± SE difference between tonometric readings: ALL, 12.8 ± 2.5 mm Hg; PLL, 5.9 ± 1.7 mm Hg; subluxation, 2.8 ± 0.8 mm Hg). Median (range) differences between rebound and applanation tonometer readings for dogs with ALL was 5 mm Hg (–9 to 76 mm Hg), with PLL was 3 mm Hg (–1 to 19 mm Hg), and with lens subluxation was 3 mm Hg (–9 to 18 mm Hg). In eyes with ALL, rebound tonometer readings exceeded applanation tonometer readings on 44 of 60 (73%) occasions.

CONCLUSIONS AND CLINICAL RELEVANCE

Rebound tonometry yielded higher estimates of IOP than did applanation tonometry in eyes with ALL and with all types of lens luxation considered collectively. Estimates of IOP in eyes with lens instability should ideally be obtained with both rebound and applanation tonometers. Veterinarians with only one type of tonometer should interpret results for dogs with lens instability concurrent with physical examination findings.

Full access
in Journal of the American Veterinary Medical Association

Abstract

On September 30, 2016, the US National Veterinary Services Laboratory confirmed an autochthonous case of New World screwworm infestation in a Key deer (Odocoileus virginianus clavium) from Big Pine Key, Fla. This case marked the first identification of a sustained and reproducing population of New World screwworm flies in the United States since 1966. Multiple federal, state, and local government agencies collaborated to initiate a response to the outbreak. Efforts were successful in eradicating the flies from Florida.

Full access
in Journal of the American Veterinary Medical Association