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Five related Boer goat kids (≤4 months of age) were presented to the University of Missouri, Veterinary Teaching Hospital (MU-VMTH) with epiphora and blepharospasm of several weeks duration and commencing prior to 1 month of age in all animals. Clinical examination confirmed euryblepharon and entropion bilaterally in two females and one male and unilaterally in two female kids. Deep stromal corneal ulceration was present in two eyes, and corneal granulation tissue and fibrosis were present in half (5/10) the affected eyes. A combination Hotz-Celsus and lateral eyelid wedge resection procedure was performed on all affected eyelids. Recheck examinations and long-term follow-up confirmed resolution of the entropion, preservation of normal eyelid conformation, and restoration of ocular comfort. Pedigree analysis ruled out sex-linked and autosomal dominant inheritance patterns; a specific mode of inheritance could not be determined. The Boer goat breed may be at increased risk for the development of entropion. This cases series represents the first report of entropion in the caprine species.

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Presented here is a draft genome sequence for Staphylococcus agnetis CBMRN 20813338, isolated from a lactating dairy cow with subclinical mastitis. The genome is approximately 2,416 kb and has 35.79% G+C content. Analysis of the deduced open reading frame (ORF) set identified candidate virulence attributes in addition to potential molecular targets for species identification.

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Coagulase-negative staphylococcal species are a common cause of subclinical bovine mastitis, with Staphylococcus chromogenes being one of the most frequently identified species in these cases. The draft genome sequence of an S. chromogenes isolate (MU 970) recovered from the milk of a cow with a chronic intramammary infection is reported here.

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OBJECTIVE: To determine pharmacokinetic and pharmacodynamic properties of midazolam after IV and IM administration in alpacas. ANIMALS: 6 healthy alpacas. PROCEDURES: Midazolam (0.5 mg/kg) was administered IV or IM in a randomized crossover design. Twelve hours prior to administration, catheters were placed in 1 (IM trial) or both (IV trial) jugular veins for drug administration and blood sample collection for determination of serum midazolam concentrations. Blood samples were obtained at intervals up to 24 hours after IM and IV administration. Midazolam concentrations were determined by use of tandem liquid chromatography-mass spectrometry. RESULTS: Maximum concentrations after IV administration (median, 1,394 ng/mL [range, 1,150 to 1,503 ng/mL]) and IM administration (411 ng/mL [217 to 675 ng/mL]) were measured at 3 minutes and at 5 to 30 minutes, respectively. Distribution half-life was 18.7 minutes (13 to 47 minutes) after IV administration and 41 minutes (30 to 80 minutes) after IM administration. Elimination half-life was 98 minutes (67 to 373 minutes) and 234 minutes (103 to 320 minutes) after IV and IM administration, respectively. Total clearance after IV administration was 11.3 mL/min/kg (6.7 to 13.9 mL/min/kg), and steady-state volume of distribution was 525 mL/kg (446 to 798 mL/kg). Bioavailability of midazolam after IM administration was 92%. Peak onset of sedation occurred at 0.4 minutes (IV) and 15 minutes (IM). Sedation was significantly greater after IV administration. CONCLUSIONS AND CLINICAL RELEVANCE: Midazolam was well absorbed after IM administration, had a short duration of action, and induced moderate levels of sedation in alpacas.

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The occurrence of Clostridium difficile infections in patients that do not fulfill the classical risk factors prompted us to investigate new risk factors of disease. The goal of this study was to characterize strains and associated antimicrobial resistance determinants of C. difficile isolated from swine raised in Ohio and North Carolina. Genotypic approaches used include PCR detection, toxinotyping, DNA sequencing, and pulsed-field gel electrophoresis (PFGE) DNA fingerprinting. Thirty-one percent (37/119) of isolates carried both tetM and tetW genes. The ermB gene was found in 91% of isolates that were resistant to erythromycin (68/75). Eighty-five percent (521/609) of isolates were toxin gene tcdB and tcdA positive. A total of 81% (494/609) of isolates were positive for cdtB and carry a tcdC gene (a toxin gene negative regulator) with a 39-bp deletion. Overall, 88% (196/223) of pigs carry a single C. difficile strain, while 12% (27/223) of pigs carried multiple strains. To the best of our knowledge, this is the first report of individual pigs found to carry more than one strain type of C. difficile. A significant difference in toxinotype profiles in the two geographic locations was noted, with a significantly (P < 0.001) higher prevalence of toxinotype V found in North Carolina (84%; 189/224) than in Ohio (55%; 99/181). Overall, the study findings indicate that significant proportions of C. difficile in swine are toxigenic and often are associated with antimicrobial resistance genes, although they are not resistant to drugs that are used to treat C. difficile infections.

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Dynamic changes in neuroinflammation and glutamate NMDA receptors (NMDAR) have been noted in traumatic and ischemic brain injury. AIM: Here we investigate the time course and regional distribution of these changes and their relationship with atrophy in a rat model of penetrating brain injury. MATERIALS METHODS: Quantitative autoradiography, with the neuroinflammation marker [3H]PK11195 and the NMDAR antagonist [125I]iodoMK801, was performed on brains of animals subjected to a unilateral wireknife injury at the level of striatum and killed 3 - 60 days later. Regional atrophy was measured by morphometry. RESULTS: The injury produced large increases in [3H]PK11195 binding density in cortical and septal regions adjacent to the knife track by day 7, with modest increases in the striatum. [125I]iodoMK801 binding was reduced in cor tical and hippocampal regions showing marked neuroinflammation, which showed marked atrophy at subsequent time points. CONCLUSION: These results indicate that neuroinflammaton and loss of NMDAR precede and predict tissue atrophy in cortical and hippocampal regions.

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OBJECTIVE: To estimate prevalence and determine association between antimicrobia resistance and toxin gene profile of Clostridium difficile in commercial pigs at the preharvest food-safety level. ANIMALS: 68 sows and 251 young pigs from 5 farms in North Carolina and 3 in Ohio. PROCEDURES: Fecal samples were collected from sows (8/farm) and matched young pigs (32/farm) at farrowing and again at the nursery and finishing stages. Clostridium difficile isolates were tested for susceptibility to 6 antimicrobials. A PCR assay was used to detect genes coding for enterotoxin A (tcdA), cytotoxin B (tcdB), and binary toxin (cdtB). RESULTS: C difficile prevalence in young pigs at farrowing was 73% (n=183) with significantly higher prevalence in Ohio (875%) than in North Carolina (64%). Clostridium difficile was isolated from 32 (47%) sows with no significant difference between the 2 regions. A single pig had a positive test result at the nursery, and no isolate was recovered at the finishing farms. Resistance to ciprofloxacin was predominant in young pigs (91.3% of isolates) and sows (94%). The antimicrobial resistance profile ciprofloxacin-erythromycin-tetracycline was detected in 21.4% and 11.7% of isolates from young pigs and sows, respectively. Most isolates had positive results for tcdA (65%), tcdB (84%), and the binary toxin cdtB (77%) genes. Erythromycin resistance and tetracycline resistance were significantly associated with toxin gene profiles. CONCLUSIONS AND CLINICAL RELEVANCE: The common occurrence of antimicrobial-resistant C difficile and the significant association of toxigenic strains with antimicrobial resistance could contribute to high morbidity in farms with farrowing pigs.

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CTX-M extended-spectrum ß-lactamases are enzymes produced by bacteria that are capable of inhibiting the antimicrobial effects of cephalosporin drugs. Recently, the first domestically acquired Salmonella in the United States expressing bla(CTX-M) was reported. This is a concern because expanded-spectrum cephalosporins are the treatment of choice for invasive Gram-negative infections, including salmonellosis in children. Because Salmonella transmission is primarily foodborne, there is also concern that resistant enteric bacteria from livestock can be transferred through the food supply chain to consumers. bla(CTX-M) has not been previously identified in bacterial isolates from food animal populations in the United States. We report the recovery of CTX-M-type extended-spectrum ß-lactamases from fecal Escherichia coli of sick and healthy dairy cattle in Ohio. Four individual fecal samples yielded E. coli isolates representing three clonal strains that carried bla(CTX-M) on transferable plasmids. Two distinguishable plasmids were identified, each encoding bla(CTX-M-1) or bla(CTX-M-79). Transferrable bla(CTX-M) genes in bovine E. coli have the potential to serve as a reservoir of resistance for pathogens and may represent a public health concern.

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This study investigated the roles of various environmental sources, such as truck-washing systems, waste-processing lagoons, and other sources, as potential contributors to the exposure and dissemination of Salmonella in commercial swine production systems. Four cohorts of nursery age swine herds which originated from distinct farm flows were selected. In addition, cross-sectional sampling of four truck wash stations selected based on the types of disinfectants and sources of water used for sanitizing trucks were tested. Salmonella isolates were recovered from pigs (feces, cecal contents, and mesenteric lymph nodes) and environmental sources (barn floor, lagoon, barn flush, trucks, and holding pens). Antimicrobial susceptibility testing and genotyping were conducted using Kirby-Bauer disk diffusion and amplified fragment length polymorphism, respectively. Salmonella prevalence significantly increased with age from late nursery to slaughter for all of the cohorts (P = 0.007). In two of three instances, all three pig holding pens (lairage) sampled at processing were Salmonella positive. The predominant antibiotypes for all sources included ACSSuT (51.8%), SSuT (16.8%), T (6%), and pansusceptible (7.4%). For the isolates obtained at the farms, the ACSSuT phenotype was 5.6 times more likely to be found in the animals than in the environment (95% confidence interval, 4.4 to 7.2 times). Serogroup B was the most common serogroup (79%), followed by serogroup E (10.4%). Despite the fact that the four production flows were independent, 1 of the 11 genotypic clusters (cluster A1) was commonly detected in any type of sample regardless of its origin. Five of the genotypic clusters (clusters A3, A4, A5, A6, and A7) contained isolates that originated from trucks and lairage swabs and also from cecal contents and/or mesenteric lymph nodes. More interestingly, genotypic clusters A3, A4, and A6 (but not clusters A5 and A7) were not detected on the farms. They originated from the trucks and lairage swabs and then were identified from the cecal contents and/or mesenteric lymph nodes. These findings underscore the significance of various environmental factors, including inadequate truck-washing systems, and emphasize the role of lairage contamination by Salmonella that has food safety significance.

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Traumatic brain injury is a leading cause of mortality and morbidity among young people. For the last couple of decades, it was believed that excess stimulation of brain receptors for the excitatory neurotransmitter glutamate was a major cause of delayed neuronal death after head injury, and several major clinical trials in severely head injured patients used blockers of the glutamate N-methyl-D-aspartate (NMDA) receptor. All of these trials failed to show efficacy. Using a mouse model of traumatic brain injury and quantitative autoradiography of the activity-dependent NMDA receptor antagonist MK801, we show that hyperactivation of glutamate NMDA receptors after injury is short-lived (<1 h) and is followed by a profound and long-lasting (> or =7 days) loss of function. Furthermore, stimulation of NMDA receptors by NMDA 24 and 48 h postinjury produced a significant attenuation of neurological deficits (blocked by coadministration of MK801) and restored cognitive performance 14 days postinjury. These results provide the underlying mechanism for the well known but heretofore unexplained short therapeutic window of glutamate antagonists after brain injury and support a pharmacological intervention with a relatively long (> or =24 h) time window easily attainable for treatment of human accidental head injury.

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