Equine Gunshot Euthanasia: Creation of a 3D-Printed Model with Integrated Sensors for Training

Challenges and issues related to the use of pentobarbital euthanasia and disposal of animal remains within the US have recently been reviewed. Environmental and public health challenges increasingly necessitate consideration of alternative methods such as gunshots, an American Veterinary Medical Association (AVMA) "acceptable with conditions" method, for the humane euthanasia of horses. A recent study reported a correctly aimed gunshot provides a humane option for euthanizing horses. However, although aiming guidelines exist, studies examining bullet trajectories in animals euthanized by gunshot have reported that inadequate disruption of the brain is a serious welfare issue. Here, we report the development and production of a portable, reusable, equine gunshot euthanasia training model. Using 3D printing, an anatomically accurate model of an equine head has been developed, with external aiming landmarks and equipped with integrated laser sensors and LED eyes. The laser sensors are embedded in two specific anatomical tracts (pons and medulla) with aiming paths associated with the aiming landmarks to train correct aiming angle. The LED eyes are linked to the laser sensors to provide instant feedback on aiming accuracy. When a beam from a commercially available blue training gun laser travels along the correct aiming path and strikes the sensor inside the head, the lights in the model's eyes go out and there is an audible signal, providing immediate feedback on the accuracy of the shot. The model facilitates the training of veterinary personnel and first responders in successful gunshot euthanasia, providing instantaneous feedback on the likelihood of a shot causing immediate, humane death in a live animal.

An implantable helmet for studying repeat TBI

An estimated 3.8 million traumatic brain injuries (TBI) occur each year, the majority classified as mild. Interest in models of mild and repeat mild TBI has grown due to reports of lasting morbidity following sports- or combat-related injury. There remains a paucity of data linking cellular or systems-related mechanisms to behavioral outcomes following repeat mild TBI, particularly in adolescent and adult rats. It is critical, therefore, to develop flexible models to evaluate which parameters of injury are associated with brain vulnerability or poor chronic outcome compared to normal recovery. While there are several existing models of repeat mild TBI in rodents, studying the effects of multiple hits has been complicated by the need for multiple survival surgeries, extensive pre-injury anesthesia time, and limitations due to animal skull thickness.•We developed a chronic "helmet" implant by combining aspects of the Impact Acceleration and Controlled Cortical Impact models.•Implants were performed days before injury, allowing us to decouple surgery from TBI. Critically, by pre-implanting the animals, only minimal anesthesia was required to position them under the impactor.•The implant allows for flexibility in the number and severity of injuries and interval between impacts.

Trichinella spiralis in a South American sea lion (Otaria flavescens) from Patagonia, Argentina

Trichinella spp. from a sylvatic cycle has been found in several animal species such as pumas (Puma concolor), armadillos (Chaetophractus villosus), rats (Rattus norvegicus), and wild boars (Sus scrofa) in Argentina. Moreover, Trichinella infection has been detected in a wide range of marine mammals around the world, including polar bears (Ursus maritimus) and walruses (Odobenus rosmarus). Until the present time, Trichinella spp. infection has not been detected in marine mammals of South America. Samples from four South American sea lions (Otaria flavescens) found dead in Rio Negro, Argentina, were analyzed by artificial digestion, and in the case of one animal, Trichinella larvae were identified at the species level by nested multiplex PCR as Trichinella spiralis. This is the first report of a Trichinella species infecting marine mammals from South America.

The application of 3-dimensional printing for preoperative planning in oral and maxillofacial surgery in dogs and cats

OBJECTIVE

To describe the application of 3-dimensional (3D) printing in advanced oral and maxillofacial surgery (OMFS) and to discuss the benefits of this modality in surgical planning, student and resident training, and client education.

STUDY DESIGN

Retrospective case series.

ANIMALS

Client-owned dogs (n = 28) and cats (n = 4) with 3D printing models of the skulls.

METHODS

The medical records of 32 cases with 3D printing prior to major OMFS were reviewed.

RESULTS

Indications for 3D printing included preoperative planning for mandibular reconstruction after mandibulectomy (n = 12 dogs) or defect nonunion fracture (n = 6 dogs, 2 cats), mapping of ostectomy location for temporomandibular joint ankylosis or pseudoankylosis (n = 4 dogs), assessment of palatal defects (n = 2 dogs, 1 cat), improved understanding of complex anatomy in cases of neoplasia located in challenging locations (n = 2 dogs, 1 cat), and in cases of altered anatomy secondary to trauma (n = 2 dogs).

CONCLUSION

In the authors' experience, 3D printed models serve as excellent tools for OMFS planning and resident training. Furthermore, 3D printed models are a valuable resource to improve clients' understanding of the pet's disorder and the recommended treatment.

CLINICAL RELEVANCE

Three-dimensional printed models should be considered viable tools for surgical planning, resident training, and client education in candidates for complex OMFS.

Anthropomorphic Phantoms for Confirmation of Linear Accelerator-Based Small Animal Irradiation

Three dimensional (3D) scanning and printing technology is utilized to create phantom models of mice in order to assess the accuracy of ionizing radiation dosing from a clinical, human-based linear accelerator. Phantoms are designed to simulate a range of research questions, including irradiation of lung tumors and primary subcutaneous or orthotopic tumors for immunotherapy experimentation. The phantoms are used to measure the accuracy of dose delivery and then refine it to within 1% of the prescribed dose.

Flexible integration of high-imaging-resolution and high-power arrays for ultrasound-induced thermal strain imaging (US-TSI)

Ultrasound-induced thermal strain imaging (USTSI) for carotid artery plaque detection requires both high imaging resolution (<100 μm) and sufficient US-induced heating to elevate the tissue temperature (~1°C to 3°C within 1 to 3 cardiac cycles) to produce a noticeable change in sound speed in the targeted tissues. Because the optimization of both imaging and heating in a monolithic array design is particularly expensive and inflexible, a new integrated approach is presented which utilizes independent ultrasound arrays to meet the requirements for this particular application. This work demonstrates a new approach in dual-array construction. A 3-D printed manifold was built to support both a high-resolution 20 MHz commercial imaging array and 6 custom heating elements operating in the 3.5 to 4 MHz range. For the application of US-TSI in carotid plaque characterization, the tissue target site is 20 to 30 mm deep, with a typical target volume of 2 mm (elevation) × 8 mm (azimuthal) × 5 mm (depth). The custom heating array performance was fully characterized for two design variants (flat and spherical apertures), and can easily deliver 30 W of total acoustic power to produce intensities greater than 15 W/cm(2) in the tissue target region.

What are the barriers to medical care for patients with newly diagnosed diabetes mellitus?

CONTEXT

Few data are available describing factors that prevent patients with newly diagnosed diabetes from seeking medical care.

OBJECTIVE

To identify socioeconomic factors that act as barriers to healthcare among such patients.

SETTING

A community-wide diabetes screening programme.

PARTICIPANTS

One hundred and eighteen patients with newly identified diabetes mellitus out of 1,824 total screenings.

INTERVENTIONS

Each newly identified person with diabetes was instructed to contact a physician for follow-up care.

DESIGN

A follow-up survey was obtained from 89 (75%) subjects 9 +/- 7 months after diagnosis.

MAIN OUTCOME MEASURE

Whether or not subjects had obtained follow-up care for their diabetes.

RESULTS

Of seven variables examined, only lack of health insurance correctly predicted those patients who failed to seek medical care for their diabetes by multivariate analysis.

CONCLUSIONS

Lack of health insurance coverage is the primary reason that patients with newly diagnosed diabetes fail to seek medical care.

Diurnal rhythm of core body temperature is phase advanced in a rodent model of depression

We examined the diurnal rhythm of core body temperature in a strain of rats with an upregulated central muscarinic receptor system. The Flinders-Sensitive Line (FSL) was derived by selectively breeding rats for sensitivity to cholinergic agonists. When compared to control rats, the FSL rats showed a remarkably strong phase advance of the acrophase in body temperature during a standard light-dark schedule. Some patients with some types of depression also show phase advances in a number of circadian rhythms, including temperature. Our finding of a phase advance in a rodent model with a known upregulated muscarinic receptor system is compatible with both the phase advance and the muscarinic overdrive theories of depression. These findings also further validate the usefulness of the FSL rats in the study of depression.

Effects of sleep deprivation on sleepiness and increased REM sleep in rats selectively bred for cholinergic hyperactivity

In this study we employed a modification of the multiple sleep latency test (MSLT) to determine whether rats of a strain with increased cholinergic activity were sleepier compared to randomly bred control rats. Seven rats each from the Flinders sensitive line (FSL, hypercholinergic) and Flinders resistant line (FRL, age-matched controls) were kept awake for 20 min and then allowed to sleep ad libitum for 20 min. The regimen of 20 min of wakefulness followed by 20 min of sleep was repeated 12 times during the day. There were no differences in latency to sleep or to rapid eye movement (REM) sleep or in percent total sleep time, drowsy, or slow-wave sleep between FSL rats and FRL rats. However, FSL rats showed a significant increase in REM sleep compared to FRL rats. This selective increase in REM sleep may be coupled to an increase in brain muscarinic receptors in the FSL rats.

Ovine estrus synchronization and superovulation using norgestomet B and follicle stimulating hormone-pituitary

Finewooled Rambouillet range ewes were used in a study to determine the feasibility of using a progesterone ear implant to synchronize estrus. In addition, some of the ewes were further treated with injections of follicle stimulating hormone-pituitary (FSH-P) to induce superovulation. Five days following estrus detection and breeding, FSH-P-treated ewes were laparotomized and surgically flushed to recover embryos. The number of corpora lutea (CL), the total number of embryos and the number of transferable embryos recovered were recorded along with the number and size of follicles present on both ovaries. Ewes synchronized as recipients were laparotomized for surgical transfer of embryos 5 d following estrus. The number of CL and follicles were recorded. Response to superovulation by FSH-P did not differ (P>0.05) between age groups of ewes when the number of CL present was counted. However, the total number of embryos flushed and good embryos was lower (P<0.05) among the oldest (7 yr) ewes. The number of follicles present showed little variation between age groups. Recipient ewes (No FSH-P) were similar in the number of CL with 6-yr-old ewes, having fewer (P>0.05) CL, than 3-, 4- or 7-yr-old ewes. Only slight variation was boserved in the number of follicles in recipient ewes. Among donor ewes receiving FSH-P in addition to Synchro-Mate B, 71% were detected in estrus within 48 h of implant removal vs 55% of the recipients.

Teaching clinical skills to pre-clinical medical students: integration with basic science learning

Clinical skills are usually learned by pre-clinical students in a manner divorced from their basic science foundations. The value of previously learned basic sciences thus fails to be re-enforced. A clinical skills course was developed for an experimental curriculum of medical students in their first year. It was organized and taught by a team of basic and clinical scientists and emphasized the basic pathophysiological principles underlying clinical skills. Sessions were supported by related basic science audiovisual resources and a series of clinical problems with questions obliging the student to reason through basic-science mechanisms. Over the span of the course, students' interest shifted dramatically from a focus on proficiency in motor skills to an understanding of basic pathophysiological mechanisms underlying observed phenomena. Compared to conventional curriculum students, those in the experimental curriculum failed to show a diminution in perceived value of basic sciences in their future career and, on cumulative, cognitive examinations, scored equally in basic science, but significantly higher in clinical science subjects. A clinical skills course integrating both teachers and concepts from basic, as well as clinical sciences can improve student attitudes toward basic sciences.