Antimicrobial susceptibility of bacteria isolated from neonatal foal samples submitted to a New Zealand veterinary pathology laboratory (2004 to 2013)

AIMS: To describe antimicrobial susceptibility, and identify antimicrobial resistance (AMR), in bacteria isolated from New Zealand foals.

METHODS: A database search was performed of submissions to a veterinary pathology laboratory between April 2004 and December 2013 for bacterial culture of samples from foals <3 weeks of age. Culture and susceptibility results were compiled with demographic information. Susceptibility results were as defined for the Kirby-Bauer disk diffusion susceptibility test based on Clinical Laboratory Standards Institute guidelines. Multi-drug resistance (MDR) was defined as non-susceptibility to ≥3 of a panel of antimicrobials (ceftiofur, enrofloxaxin, gentamicin, penicillin, tetracycline, trimethoprim-sulfonamide); penicillin susceptibility was not included for Gram-negative isolates.

RESULTS: Submissions from 102 foals were examined, and 127 bacterial isolates were cultured from 64 (63%) foals. Of the 127 isolates, 32 (25%) were Streptococcus spp., 30 (24%) were Staphylococcus spp., 12 (10%) were Enterococcus spp. and 26 (21%) were Escherichia coli. Of 83 Gram-positive isolates, 57 (69%) were susceptible to penicillin. Over all isolates, 92/126 (73%) were susceptible to gentamicin and 117/126 (93%) to enrofloxacin; 62/82 (76%) of Gram-positive, and 22/42 (52%) of Gram-negative bacteria were susceptible to ceftiofur; 53/81 (65%) of Gram-positive, and 23/44 (52%) of Gram-negative bacteria were susceptible to tetracycline; 59/82 (72%) of Gram-positive, and 23/44 (43%) of Gram-negative bacteria were susceptible to trimethoprim-sulfonamide. Of 126 isolates, 33 (26%) had MDR; >1 isolate with MDR was cultured from 24/64 (38%) foals, and ≥2 isolates with MDR were recovered from 8/64 (13%) foals.

CONCLUSIONS: Multi-drug resistance, including resistance to commonly used antimicrobials, was found in bacterial isolates from foals in New Zealand.

CLINICAL RELEVANCE: The results of this study are of concern from a treatment perspective as they indicate a potential for antimicrobial treatment failure. For future surveillance of AMR and the creation of national guidelines, it is important to record more data on samples submitted for bacterial culture.     

Use of chemical ablation with trichloroacetic acid to treat eyelid apocrine hidrocystomas in a cat

CASE DESCRIPTION: A 7-year-old Persian cat was evaluated for recurrence of multiple cystic periocular masses. A number of cyst-like lesions had been resected from the left eyelids 18 months earlier, with lesions recurring within 6 months after surgery. The cat had blepharospasm and signs of discomfort following rupture of the largest cyst the day prior to examination. Previous histologic examination of the cysts had revealed apocrine hidrocystomas. CLINICAL FINDINGS: Multiple pigmented nodules were seen around the skin of the upper and lower left eyelids. The nodules were brownish to black, round, soft, and fluid-filled. Signs of pain were not evident during palpation of the nodules. TREATMENT AND OUTCOME: The largest cyst on the upper eyelid was removed by means of a V-shaped full-thickness excision. Histologic and immunohistochemical examination of the excised tissue confirmed the diagnosis of apocrine hidrocystoma. The remaining periocular cysts were surgically debrided and then treated topically with 20% trichloroacetic acid. All lesions healed rapidly without any signs of discomfort. During a recheck examination 12 months later, the upper and lower left eyelids appeared morphologically normal, and there was no evidence of recurrence. CLINICAL RELEVANCE: Findings suggested that chemical ablation with trichloroacetic acid may be a useful treatment for apocrine hidrocystomas in cats.     

Cloning and characterization of a plant defensin VaD1 from azuki bean

A recombinant mungbean defensin VrD1 was previously shown to exhibit antifungal and bruchid-resistant activity. To study the function and regulation of VrD1, genomic DNAs of plant defensins were isolated from Vigna radiata VC6089A and azuki bean Vigna angularis Kao Hsiung No. 6. The azuki bean defensin genomic DNA VaD1 was sequenced and converted to VaD1 cDNA. VaD1 defensin was purified from Vigna angularis Kao Hsiung No. 6 to apparent homogeneity. The complete amino acid sequence of the purified VaD1 was determined and was found to be exactly the same as the sequence deduced from VaD1 cDNA. VaD1 is a basic protein containing 46 amino acids with four conserved disulfide bonds and shares high sequence homology (78.3%) with VrD1. VaD1 inhibited the growth of Fusarium oxysporum, Fusarium oxysporum f. sp. pisi, Staphylococcus epidermidis, and Salmonella typhimurium. VaD1 also inhibited in vitro protein synthesis and bruchid larval development, but was less active than the recombinant VrD1.     

The determination of semicarbazide (N-aminourea) in commercial bread products by liquid chromatography-mass spectrometry

Recently, semicarbazide has been found in food in jars sealed with cap liners that were manufactured using azodicarbonamide as a blowing agent. These reports raised the concern that the use of azodicarbonamide-an approved dough conditioner-may result in semicarbazide residues in bread. To answer this question, a method based upon the previously reported liquid chromatography/tandem mass spectrometry determination of the semicarbazone of o-nitrobenzaldehyde was utilized. The method adopted for this work includes an extensive cleanup and reaction with o-nitrobenzaldehyde at pH 3.5, rather than with the widely used 0.1 M HCl, to form the semicarbazone derivative. A stable isotope dilution assay was used to determine the free semicarbazide present in the bread products. Levels of semicarbazide ranged from 10 to 1200 ppb in commercial bread products with azodicarbonamide listed among their ingredients.     

Response of the soil bacterial community to the addition of toluene and toluene-degrading bacteria

Changes in soil bacterial communities after toluene and/or toluene degrading bacteria were added were monitored by growth on various media, and by the culture-independent method of Reverse Sample Genome Probing (RSGP). A total of 397 isolates that were cultured from toluene-amended and non-amended soil were identified using fatty acid methyl ester (FAME) analysis. In 75% of the soil samples, gram-positive bacteria dominated, primarily Bacillus sp. and Cellulomonas sp. In contrast, RSGP revealed Proteobacteria (α, β, and γ subgroups) to be the dominant species, with Bacillus sp. dominant in only one soil sample.In toluene-treated soil, FAME and RSGP analyses indicated that by day 5 the major bacterial populations were gram-negative bacteria, in particular, Pseudomonas sp., Acinetobacter sp., and Alcaligenes sp. When toluene and Pseudomonas putida D8 were coincidentally introduced, the proportion of Pseudomonas sp. in the bacterial population recovered using non-selective medium increased from 16 to 62% and then rapidly decreased to about 9%. When we used selective medium to monitor the population of P. putida D8, a rapid initial increase followed by a gradual decline was also observed. In samples analyzed by RSGP, D8 was one of the major species of the bacterial community at day 2, but its signal intensity dropped to 9.5% by day 5.The influence of D8 addition on the bacterial profile was monitored in growth-based examinations. Bacillus sp. and Pseudomonas sp. were initially dominant. By day 5, Bacillus sp. decreased while the Proteobacteria, (including Acinetobacter sp., Agrobacterium sp., Alcaligenes sp., Burkholderia sp., Erwinia sp., and Pseudomonas sp.) increased. At the same time, D8 decreased to a level indistinguishable from background. Conversely, RSGP analysis revealed the population dominance of P. putida (including D8) and Rhizobium fredii at day 2. Populations shifted toward Agrobacterium tumefaciens, Bacillus subtilis, R. fredii, and D8 by day 5.P. putida D8 levels could be monitored using RSGP when cultivation failed. However, cultivation of Bacillus sp. was always successful, while the organism was only occasionally detected by RSGP. While cultivation and RSGP methods comparably detected the same major bacterial populations, the overall bacterial diversity was greater with RSGP than with growth-based testing.     

Association of increased serum acute‐phase protein concentrations with reproductive performance in dairy cows with postpartum metritis

Background: It is known that quantification of bovine acute‐phase proteins could routinely provide early diagnostic and prognostic information for monitoring herd health status. Objective: The aim of this study was to test the hypothesis that haptoglobin (Hp) and serum amyloid A (SAA) have the potential for indicating uterine infection, mainly due to subclinical endometritis, which can seriously influence the reproductive performance in dairy cows. Methods: A total of 264 serum samples were collected from 24 Holstein dairy cows at defined intervals from 1 week prepartum to 6 months postpartum. Clinically healthy animals (Group 1, n=6) were compared with 24 animals having acute puerperal metritis (Group 2, n=18) and with concentrations obtained from healthy heifers (baseline values, n=10). The concentrations of serum Hp and SAA were measured using a hemoglobin‐binding assay and Western blot analysis, respectively. Reproductive performance was assessed as the number of days open and the conception rate at the end of the study. Results: Upper cut‐off values for Hp and SAA concentrations in heifers were 130.9 μg/L and 51.9 μg/mL, respectively. Hp concentrations in Group 2 were significantly higher than those in Group 1 at all time points (P<.001). Additionally, among the successfully pregnant animals, the number of days open was significantly higher in 6 cows with Hp >130.9 μg/mL (median=316 days) than in 11 cows with Hp ≤130.9 μg/mL (median=120 days) (P=.0024). Conclusions: Serum Hp and SAA concentrations can be used to recognize uterine infection in postpartum cows. The association between elevated Hp values and number of days open suggests Hp may also be a useful indicator of poor prognosis for reproductive performance.     

Trace element water improves the antioxidant activity of buckwheat (Fagopyrum esculentum Moench) sprouts

Buckwheat (Fagopyrum esculentum Moench) was grown in trace element water (TEW) (100, 200, 300, 400, and 500 ppm) and deionized water (DIW) to evaluate whether the beneficial effects of trace elements on the antioxidant activity could be accomplished with the supplement of TEW. At 300 ppm, TEW significantly increased the Cu, Zn, Mn, and Fe contents in buckwheat sprout but not the Se content. However, the levels of rutin, isoorientin, vitexin, and isovitexin did not differ between buckwheat sprouts grown in TEW and DIW. The ethanolic extract from buckwheat sprout grown in 300 ppm of TEW showed higher ferrous ion chelating activity and inhibitory activity toward lipid peroxidation than that grown in DIW. The extract in the TEW group also enhanced intracellular superoxide dismutase activity and lowered reactive oxygen species and superoxide anion in the human Hep G2 cell. It was concluded that TEW could increase the antioxidant activities of buckwheat sprouts.     

Investigation into the use of plasma NT-proBNP concentration to screen for feline hypertrophic cardiomyopathy

ObjectiveTo evaluate the utility of feline NT-proBNP plasma concentration [NT-proBNP] as a screening tool for cats with subclinical hypertrophic cardiomyopathy (HCM).Animals, materials and methodsForty adult Maine Coon or Maine Coon crossbred cats from the feline HCM research colony at the University of California, Davis were studied. All cats had previously been genotyped as heterozygous or negative for the A31P myosin binding protein C (MYBPC) mutation. Echocardiograms were performed to assess the severity of HCM in each cat. Blood samples were collected for evaluation of [NT-proBNP].ResultsIn these cats with severe HCM, [NT-proBNP] was significantly elevated (P < 0.0001) when compared to all other groups of cats and an [NT-proBNP] > 44pmol/L accurately predicted the presence of severe HCM. However, [NT-proBNP] was not increased in cats with moderate or equivocal HCM when compared to normal cats. Cats heterozygous for the MYBPC mutation had a significantly elevated [NT-proBNP] when compared to cats without the A31P mutation (P = 0.028).ConclusionsMeasurement of [NT-proBNP] has a high sensitivity and specificity as a means of detecting severe HCM in cats, but it is not sensitive for the identification of moderate HCM as judged by the evaluation of Maine Coon and Maine Coon cross cats in our colony. Consequently, we conclude that this test cannot be used to screen cats for the presence of mild to moderate HCM.     

Adrenocorticotropic hormone stimulation tests in healthy foals from birth to 12 weeks of age

The purpose of this study was to investigate total baseline plasma cortisol and adrenocorticotropic hormone (ACTH) concentrations, and ACTH-stimulated cortisol concentrations in foals from birth to 12 wk of age. Plasma (baseline) cortisol and ACTH concentrations were measured in 13 healthy foals at birth and at 1, 2, 3, 4, 5, 7, 10, 14, 21, 28, 42, 56, and 84 d of age. Each foal received cosyntropin (0.1 μg/kg) intravenously. Plasma cortisol concentrations were measured before (baseline), and 30, and 60 min after cosyntropin administration at birth and at 3, 5, 7, 10, 14, 21, 28, 42, 56, and 84 d of age. Compared with baseline, cortisol concentration increased significantly 30 min after administration of cosyntropin on all days. Cortisol concentration was highest at birth, measured at 30 and 60 min after cosyntropin administration, compared with all other days. With the exception of birth measurements, cortisol concentration was significantly higher on day 84, measured at 30 and 60 min after cosyntropin administration, when compared with all other days. Baseline plasma ACTH was lowest at birth when compared with concentrations on days 2, 3, 4, 5, 7, 10, 14, 42, 56, and 84. Administration of 0.1 μg/kg of cosyntropin, IV, reliably induces cortisol secretion in healthy foals. Differences in the magnitude of response to cosyntropin are observed depending on the age of the foal. These data should serve as a reference for the ACTH stimulation test in foals and should be useful in subsequent studies to evaluate the hypothalamic-pituitary-adrenal axis in healthy and critically ill foals.