Oxidation of diazinon and malathion by myeloperoxidase

The aim of the work was to investigate the in vitro oxidation of diazinon and malathion, organophosphorous pesticides (OPs) containing phosphorthioate group, catalyzed by enzyme myeloperoxidase (MPO). The oxidation was performed in the presence of hydrogen peroxide. The products were identified as oxon derivatives (phosphates), where the sulfur atom from thioate group was substituted by an oxygen atom. No hydrolysis products were detected after enzyme - induced oxidation. The oxidation efficiency was controlled using acethylcholinesterase (AChE) bioassay for determination of oxon derivatives concentration. The influence of OPs concentration, incubation time of OPs with MPO, as well as MPO concentration on the yield of oxo forms was investigated. Kinetic constants of MPO in oxidation of malathion and diazinon were estimated. The maximum concentration of oxo forms was achieved after 10 min incubation of OPs in 50 mM phosphate buffer (pH 6.0) with 100 nM MPO.     

Sulfentrazone adsorbed on micelle-montmorillonite complexes for slow release in soil

Interactions of the herbicide sulfentrazone with the cationic surfactants octadecyltrimethylammonium (ODTMA), hexadecyltrimethylammonium (HDTMA), and benzyldimethylhexadecylammonium (BDMHDA) have been studied for the design of slow-release formulations based on sulfentrazone adsorbed on a micelle-montmorillonite complex. Adsorbed amounts of sulfentrazone on ODTMA- and BDMHDA-montmorillonite complexes were 99.2-99.8% of that added, and desorption of herbicide in water during 24 h was low. After 10 washings in funnels with soil, only 2.6% of herbicide was released from ODTMA-montmorillonite formulations versus 100% release from the commercial formulation. The strong binding of sulfentrazone to micelles was confirmed by pH and spectroscopic measurements and was explained by the formation of ionic pairs between cationic surfactant and anionic herbicide. The ODTMA-clay and commercial formulations of sulfentrazone yield almost complete and 40% growth inhibition of green foxtail, respectively, at 700 g of active ingredient/ha. Hence, the slow release from micelle-clay formulations of sulfentrazone promotes its biological activity and reduces environmental contamination.     

Reorganizing small animal gross anatomy: improving the faculty and student experience and incorporating non-technical competency development

The organization of the small animal gross anatomy course at Washington State University's College of Veterinary Medicine was modified in several ways over a two-year period. These modifications were motivated in part by the need to accommodate a larger number of students, but also by our desire to make more efficient use of faculty and student time as well as physical resources and to give our students opportunities to develop non-technical competencies such as communication and teamwork skills. The four major changes were (1) increasing dissection group size, (2) assigning specimens to dissection groups on a rotating basis, (3) reducing the amount of dissection time relative to time spent studying prepared specimens, and (4) introducing 'transition reviews,' a limited form of peer teaching meant to emphasize peer interaction and communication skills rather than conveyance of specific and detailed subject matter. This article describes the details of these changes and evaluates their effectiveness based on faculty assessments, results from surveys of participating students, and comparison of examination performance and formal end-of-course student evaluations before and after reorganization of the course. Increasing the dissection group size and reducing per-student dissection time did not adversely affect student performance and were viewed at least neutrally or favorably by most students. Notably, the rotation of specimens and the transition reviews elicited strongly favorable responses from a large majority of students and had several beneficial effects of which students may not have been aware but which were apparent to participating faculty. Overall, the changes were well received by both faculty and students and were, in our view, of sufficient value that this course organization plan would be used regardless of class size.     

IMAGING DIAGNOSIS–PULMONARY‐TRACHEOBRONCHIAL PROLAPSE IN A NEW CALEDONIAN GIANT GECKO (RHACODACTYLUS LEACHIANUS)

A 3‐year‐old male New Caledonian giant gecko, or Leach's gecko (Rhacodactylus leachianus) presented with acute lethargy and coelomic distention. Findings from survey radiographs and an upper gastrointestinal tract contrast study were consistent with severe aerophagia, a collapsed left lung, and hyperinflation of the right lung due to suspected bronchial obstruction. The gecko was treated with conservative medical management, but was found dead 5 days after presentation. Necropsy findings showed intussusception of the proximal left lung into the left mainstem bronchus and trachea.     

Prevalence and Factors Associated with Abnormal Behaviors in Chilean Racehorses: A Direct Observational Study

Stereotypies are considered a cause and symptom of impaired welfare, and have been associated with suboptimal husbandry systems. The aim of this study was to estimate the prevalence of stereotypic and other abnormal behaviors in Chilean thoroughbreds by direct observation, and examine their associations with biological characteristics and management practices. Seven hundred forty-three racehorses were observed directly, every 5 minutes during 1 hour before and after feeding, to identify behavioral disorders. A questionnaire was administered to handlers to obtain information about the animal and husbandry practices.     

Prostatic abscess in a neutered cat

A 6-year-old, male castrated domestic shorthair cat was presented for evaluation of lethargy, vomiting, anorexia, and constipation. Physical examination revealed an elevated body temperature and an extramural colonic mass. Abdominal ultrasonography demonstrated a hypoechoic mass measuring 2.2 cm in maximum dimension immediately caudal to the bladder. Cytological evaluation of a fine-needle aspirate confirmed the mass was a prostatic abscess. Abdominal celiotomy and prostatic omentalization were successful in resolving clinical abnormalities. Feline prostatic abscessation is a rare condition that has not been previously reported and may have a good outcome if treated early and appropriately.     

Pharmacokinetics and physiologic/behavioral effects of buprenorphine administered sublingually and intravenously to neonatal foals

Buprenorphine is absorbed following sublingual administration, which would be a low‐stress delivery route in foals. However, the pharmacokinetics/pharmacodynamics are not described in foals. Six healthy foals <21 days of age participated in a blinded, randomized, 3‐period, 5‐sequence, 3‐treatment crossover prospective study. Foals received 0.01–0.02 mg/kg buprenorphine administered SL or IV with an equivalent volume of saline administered by the opposite route. Blood was collected from the cephalic vein for pharmacokinetic analysis. Physiologic parameters (HR, RR, body temperature, GI sounds), locomotion (pedometer), and behavioral data (activity level, nursing time, response to humans) were recorded. Plasma concentration of buprenorphine exceeded a presumed analgesic level (0.6 ng/ml) in five foals in the IV group and one in the SL group but only for a very brief time. Pharmacokinetic analysis following IV administration demonstrated a short elimination half‐life (t_1/2β 1.95 ± 0.7 hr), large volume of distribution (6.46 ± 1.54 L/kg), and a high total clearance (55.83 ± 23.75 ml/kg/min), which differs from adult horses. Following SL administration, maximum concentrations reached were 0.61 ± 0.11 ng/ml and bioavailability was 25.1% ± 10.9%. In both groups, there were minor statistical differences in HR, RR, body temperature, locomotion, and time spent nursing. However, these differences were clinically insignificant in this single dose study, and excitement, sedation, or colic did not occur.