Neutrophil myeloperoxidase measurements in plasma, laminar tissue, and skin of horses given black walnut extract

OBJECTIVE: To compare measurements of myeloperoxidase (MPO) in plasma, laminar tissues, and skin obtained from control horses and horses given black walnut heartwood extract (BWHE). ANIMALS: 22 healthy 5- to 15-year-old horses. PROCEDURES: Horses were randomly assigned to 4 groups as follows: a control group given water (n = 5) and 3 experimental groups given BWHE (17) via nasogastric intubation. Experimental groups consisted of 5, 6, and 6 horses that received BWHE and were euthanatized at 1.5, 3, and 12 hours after intubation, respectively. Control horses were euthanatized at 12 hours after intubation. Plasma samples were obtained hourly for all horses. Laminar tissue and skin from the middle region of the neck were harvested at the time of euthanasia. Plasma and tissue MPO concentrations were determined via an ELISA; tissue MPO activity was measured by use of specific immunologic extraction followed by enzymatic detection. RESULTS: Tissues and plasma of horses receiving BWHE contained significantly higher concentrations of MPO beginning at hour 3. Laminar tissue and skin from horses in experimental groups contained significantly higher MPO activity than tissues from control horses. Concentrations and activities of MPO in skin and laminar tissues were similar over time. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, BWHE administration causes increases in MPO concentration and activity in laminar tissue and skin and the time of increased MPO concentration correlates with emigration of WBCs from the vasculature. These findings support the hypothesis that activation of peripheral WBCs is an early step in the pathogenesis of acute laminitis.     

Prevalence of virulence genes in Escherichia coli strains recently isolated from young pigs with diarrhea in the US

Enterotoxigenic Escherichia coli (ETEC)-associated post-weaning diarrhea (PWD) is economically one of the most important diseases for the swine industry. Porcine ETEC strains typically express K88 or F18 fimbria and heat-labile (LT) and/or heat-stable (STa, STb) enterotoxins. However, recent studies indicate that EAST1 toxin, adhesin involved in diffuse adherence (AIDA-I) and porcine attaching and effacing-associated factor (paa) may also be expressed by ETEC strains associated with diarrhea. To better understand the virulence factors of E. coli strains that cause PWD, we applied PCR to screen for K88, F18, F41, 987P and K99 fimbrial genes; LT, STa, STb, Stx2e and EAST1 toxic genes; and AIDA-I, paa and EAE adhesin genes in E. coli strains recently isolated from young pigs with PWD in the US. Of 304 E. coli isolates from diarrheic pigs submitted for testing, 175 (57.6%) strains possessed fimbrial genes: K88 (64.6%), F18 (34.3%), F41 (0.57%), K99 (0.57%), 987P (0); toxin genes: LT (57.7%), STb (72.6%), STa (27.4%), STx2e (17.4%), EAST1 (35%); and adhesin genes: AIDA-I (26.9%), paa (60%), EAE (1.1%). All toxin genes except the EAST1 toxin gene, were almost exclusively associated with K88+ or F18+ isolates, and most of these isolates carried multiple toxin genes. The non-fimbrial adhesin paa was found present in over half of the K88+ isolates. A total of 129 (42%) isolates carried no fimbrial genes, including 66 (21.7%) isolates that did not have any of the above virulence genes. These results suggest a broad array of virulence genes associated with PWD in pigs.     

The clinical utility of the right lateral intercostal ultrasound scan technique in dogs

When performing abdominal ultrasonography in dogs, the right aspect of the liver, porta hepatis, right kidney, right adrenal gland, pancreas, and duodenum are often not fully visible from a ventral, or subcostal, approach. The right lateral intercostal plane is an alternative approach that allows evaluation of these structures. This report provides multiple case examples that demonstrate the sonographic anatomy via the right intercostal approach. Other cases are included to demonstrate indications for this approach. Animals in which the right intercostal approach may prove most useful include large- and giant-breed dogs; deep-chested dogs; dogs with gas distention of the stomach, duodenum, and colon; dogs with microhepatia; and those with abdominal effusion and pain.     

Adrenomedullin (AM) and adrenomedullin binding protein (AM-BP) in the bovine mammary gland and milk: Effects of stage of lactation and experimental intramammary E. coli infection

Adrenomedullin (AM) has been characterized as an endogenous tissue survival factor and modulator of many inflammatory processes. Because of the increased susceptibility of the mammary gland to infection during the time surrounding parturition in the cow, we investigated how milk and tissue content of AM and its binding protein (AM-BP) might be affected by the stage of lactation and the udder health status. Milk and mammary biopsy samples were obtained from Holstein cows 21 days prior to and at various times after calving to represent the dry period and early and mid-stages of lactation. Additional cows received an intramammary challenge with Escherichia coli for immunohistochemical characterization of AM and AM-BP. Milk AM concentrations were relatively constant across the stages of lactation while AM-BP increased two-fold (P<0.04) between early and mid-lactation. Milk AM (P<0.04) and AM-BP (P<0.03) increased as somatic cell counts (SCCs) increased within a given stage of lactation. Tissue content of both (AM and AM-BP) were significantly affected by stage of lactation, lowest in the dry period and progressively increasing to peak at mid-lactation as well as increasing in association with higher levels of SCCs. Following E. coli challenge, AM increased in epithelial cells surrounding mammary alveoli presenting high levels of SCCs. The data suggest that AM and AM-BP are cooperatively regulated in the mammary gland during lactation; changes in localized tissue AM and AM-BP content reflect a dynamic regulation of these tissue factors in the bovine mammary gland consistent with their protective effects within inflamed tissue.     

An alumni survey to assess self-reported career preparation attained at a US veterinary school

The American Veterinary Medical Association (AVMA) Council on Education (COE) has challenged veterinary schools to improve self-assessment of curricular outcomes. One way to assess the quality of education is to gather feedback from alumni. To successfully gather feedback using a questionnaire, questions must be pertinent to veterinary education and include quantifiable responses. Several principles must be applied in questionnaire development to ensure that the questions address the intended issues, that questions are interpreted correctly and consistently, and that responses are quantifiable. The objectives of the questionnaire for alumni of Mississippi State University's College of Veterinary Medicine (MSU-CVM) were twofold: (1) to determine whether graduates were comparable to their US peers in terms of work opportunities and salary, and (2) to evaluate how well the CVM curriculum prepared students to begin their veterinary careers. Demographic categories used by the AVMA and published knowledge, skills, attitudes, and aptitudes of veterinary graduates were used in developing the questions. College-specific questions, such as those relating to student activities and impressions of college resources, were also incorporated. Questionnaires were mailed to participants, who could respond via the World Wide Web. Questionnaire results allowed leaders within the college to determine which aspects of alumni's experiences were exceptionally positive, which needed immediate response, and which might require further study. This article describes the application of principles in developing, administering, and analyzing responses to a questionnaire regarding veterinary education.     

Genetic basis and origin of resistance to acetolactate synthase inhibitors in Amaranthus palmeri from Spain and Italy

BACKGROUND

Amaranthus palmeri is an aggressive annual weed native to the United States, which has become invasive in some European countries. Populations resistant to acetolactate synthase (ALS) inhibitors have been recorded in Spain and Italy, but the evolutionary origin of the resistance traits remains unknown. Bioassays were conducted to identify cross-resistance to ALS inhibitors and a haplotype-based genetic approach was used to elucidate the origin and distribution of resistance in both countries.

RESULTS

Amaranthus palmeri populations were resistant to thifensulfuron-methyl and imazamox, and the 574-Leu mutant ALS allele was found to be the main cause of resistance among them. In two Spanish populations, 376-Glu and 197-Thr mutant ALS alleles were also found. The haplotype analyses revealed the presence of two and four distinct 574-Leu mutant haplotypes in the Italian and Spanish populations, respectively. None was common to both countries, but some mutant haplotypes were shared between geographically close populations or between populations more than 100 km apart. Wide genetic diversity was found in two very close Spanish populations.

CONCLUSION

ALS-resistant A. palmeri populations were introduced to Italy and Spain from outside Europe. Populations from both countries have different evolutionary histories and originate from independent introduction events. ALS resistance then spread over short and long distances by seed dispersal. The higher number and genetic diversity among mutant haplotypes from the Spanish populations indicated recurrent invasions. The implementation of control tactics to limit seed dispersal and the establishment of A. palmeri is recommended in both countries. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Risk factors influencing death prior to discharge in 302 dogs undergoing unilateral adrenalectomy for treatment of primary adrenal gland tumours

Adrenalectomies for canine adrenal tumours are associated with peri-operative morbidity and mortality. Objectives of this study included assessing the prognostic value of tumour- or surgery-related variables in predicting peri-operative mortality and overall survival in dogs undergoing adrenalectomies for primary adrenal tumours as well as pre-treatment with phenoxybenzamine on survival to discharge with pheochromocytomas specifically. A multi-institutional retrospective cohort study was performed across nine institutions. Electronic medical record searches identified 302 dogs which met the inclusion criteria. Data collected included dog-related, tumour-related, treatment-related, surgery-related, and outcome variables. Univariate and multivariable logistic regression and cox proportional hazards models were used to identify variables associated with death prior to discharge and tumour-related survival. Overall, 87% of dogs survived to discharge with a tumour-related survival time of 3.96 years. Post-operative complications were reported in 25%. Increased surgical time (p = 0.002) and pre-surgical medical treatment other than phenoxybenzamine (p = 0.024) were significantly associated with increased peri-operative mortality while ureteronephrectomy (p = 0.021), post-operative pancreatitis (p = 0.025), and post-operative aspiration pneumonia (p < 0.001) were significantly associated with decreased overall survival. Phenoxybenzamine pretreatment had no effect on peri-operative mortality. Thirty-seven of 45 (82%) dogs with pheochromocytomas not pretreated survived to discharge, and 50 of 59 (85%) dogs with pheochromocytomas pretreated with phenoxybenzamine survived to discharge (p = 0.730). This study provides information on risk factors for death prior to discharge and tumour-related survival that may help guide clinical management and owner expectations. In addition, the study findings challenge the previously reported benefit of phenoxybenzamine for pretreatment of dogs undergoing adrenalectomies for pheochromocytomas.