Anesthesia and Intubation of 10-Day Old C57BL/6J Mouse Pups for Cardiothoracic Surgery

Murine surgical models play an important role in preclinical research. Mechanistic insights into myocardial regeneration after cardiac injury may be gained from cardiothoracic surgery models in 0-14-day-old mice, the cardiomyocytes of which, unlike those of adults, retain proliferative capacity. Mouse pups up to 7 days old are effectively immobilized by hypothermia and do not require intubation for cardiothoracic surgery. Preadolescent (8-14-day-old) mouse pups, however, do require intubation, but this is challenging and there is little information regarding anesthesia to facilitate intubation. Empirical titration of ketamine/xylazine/atropine dosage regimens to body weight indicated the response to anesthesia of 10-day-old C57BL6/J mouse pups of different weights was non-linear, whereby doses of 20/4/0.12 mg/kg, 30/4/0.12 mg/kg and 50/6/0.18 mg/kg, facilitated intubation of pups weighing between 3.15-4.49 g (n=22), 4.50-5.49 g (n=20) and 5.50-8.10 g (n=20), respectively. Lower-body-weight pups required more intubation attempts than heavier pups (p<0.001). Survival post-intubation was inversely correlated with body weight (65, 70 and 80% for low-, mid- and high-weight groups, respectively, R2=0.995). For myocardial infarction surgery after intubation, a surgical plane of anesthesia was induced with 4.5% isoflurane in 100% oxygen and maintained with 2% isoflurane in 100% oxygen. Survival post-surgery was similar for the three weight groups at 92%, 86% and 88% (p=0.91). Together with refinements in animal handling practices for intubation and surgery, and to minimize cannibalization by the dam post-surgery, overall survival for the entire procedure (intubation plus surgery) was inversely correlated with body weight (55%, 60% and 70% for low-, mid- and high-weight groups, respectively, R2=0.978). Given the difficulty encountered with intubation of 10-day old pups and the associated high mortality, we recommend cardiothoracic surgery in 10-day-old pups be restricted to those weighing at least 5.5 g.

The role of aquaria in beluga research and conservation

Aquaria that care for and maintain belugas (Delphinapterus leucas) under professional care have the opportunity to contribute to the conservation of wild belugas through research, expertise in animal care and husbandry, and engaging and educating the public about threats to the species’ health and population sustainability. In an aquarium setting, belugas can be studied under controlled conditions, with known variables that are often difficult to discern when studying wild belugas. Information on nutrition, health status and environmental parameters can be easily obtained in a controlled setting. Biological samples are collected from professionally trained whales that voluntarily participate in informative experimental paradigms. Research studies in aquaria seek to contribute to the recovery and management of endangered beluga populations, such as those in Cook Inlet. Mystic Aquarium’s efforts are presented as a case study. Key research priorities address action items in the Cook Inlet Beluga Recovery Plan and include: (1) understanding the beluga immune system, microbial communities, pathogens and disease; (2) development of non-invasive methods for assessing reproductive status, body condition and health in wild whales; (3) investigation of diving physiology and the impact of altered dive patterns on health; (4) understanding reproduction, a key to recovery and sustainability of wild populations; (5) development and testing of new technologies for tracking and monitoring whales and habitat use; and (6) understanding how noise affects beluga hearing, behaviour and physiology. Expertise in animal handling, behaviour and nutrition contribute to rescue, rehabilitation and capture release efforts. Moreover, ‘students’ of all ages have the opportunity to be engaged, educated and contribute to beluga conservation.

269 Validation of an Automatic Scale Equipped with Solar Panels for Grazing Beef Cattle

Body weight (BW) is used to detect health and nutritional disorders in cattle, as well as calculate profitability of the production system based on weight gain curves. In grazing systems, measuring BW frequently implies moving animals, which is labor intense, stressful, and reduces grazing time and feed intake. All of which negatively impacts animal performance. An automated scale in the pasture can reduce labor and animal handling, while ensuring an accurate BW estimation. Our objective was to evaluate the functionality and accuracy of an automatic wireless scale system equipped with solar panels (SmartScale, C-LOCKTM), when compared to a conventional scale located at the cattle working facility. Eight multiparous beef cows were weighed in a 14-day interval for a period of 57 days with a conventional scale, while at the same time BW was measured daily with an automated scale located at the pasture in front of the water trough. This wireless system registers BW every time the animal approaches the water trough and automatically transmit it to a server via cellular network. Correlation between weighing systems was evaluated through a linear regression (R Core Team, 2019), where the adjusted R2 value was 0.99, determining an excellent linear relationship between values obtained by the conventional scale and values obtained by the automated scale. In addition, the automated scale registered the time of day, time spent in the scale, and number of daily visits. The probability to find an animal at the scale varies between 15% to 20% during daylight, decreasing under 9% during the night, with 2.56±1.50 average number of visits per day, where animals spend in average 2.94±1.84 minutes. In conclusion, the automated scale has the ability to measure BW with great precision and has potential to be used as a complimentary instrument to evaluate animal behavior in grazing systems.

PSX-B-18 Behavioral and physiological responses of ewes in hardwood silvopastures vs. open pastures

Managing livestock in silvopasture systems can help reduce heat stress and improve animal behavior and productivity. However, quantifying physiological benefits for animals in pastoral systems is challenging because the sampling procedures require animal handling; this is stressful and elevates plasma cortisol, a stress hormone. Hair cortisol (HC) is a relatively non-invasive and reliable measure of chronic stress, but it has received limited use especially in pasture systems. We compared behavioral and physiological (temperature, hair and blood cortisol) responses of ewes that grazed mid-stage hardwood silvopastures vs. open pastures. The study site consists of 0.27-ha black walnut (Juglans nigra; BW) and honeylocust (Gleditsia triacanthos; HL) silvopastures and open pasture (OP) treatments, each replicated three times. Thirty-six Katahdin ewes were assigned to one of the treatments for a 6-week summer grazing trial. Ewe weights and intravaginal temperatures were recorded routinely; trail cameras captured animal behavior. Blood was collected via jugular venipuncture; hair grown during the trial was collected from the loin region. Blood and hair cortisol concentration was determined by ELISA. Body weight gains and plasma cortisol levels did not differ among treatments. Ewes on OP had higher HC on Day-21 and Day-42 (P ≤ 0.007) and 0.5–1.0 °C hotter (P ≤ 0.04) intravaginal temperatures between 1200h-1700h than ewes on silvopasture treatments. Overall, ewes on OP spent more (P &lt; 0.001) time loafing and less (P &lt; 0.10) time lying down compared to ewes on silvopasture treatments. Trees within the silvopastures moderated ambient conditions, both reducing stress and improving the behavioral and physiological responses of ewes.

The Impact of Interpretive Messaging and Animal Handling on Visitors’ Perceptions of Animal Welfare and Empathic Reactions

Zoos are increasingly turning to ambassador animal programs to address animal welfare issues and visitors’ empathic responses. However, little is known, if or how, animal handling practices and interpretation impact attendees’ perceptions of animal welfare and/or empathy. To evaluate these effects, eight ambassador animal program videos were created employing varying combinations of animal handling (traditional/free choice), interpretive messaging (traditional/empathy-based), and choice and control language (present/absent). Online questionnaires ( N = 1,185) were used to assess participants’ environmental and empathic predispositions before viewing and perceptions of animal welfare and empathic reactions immediately after viewing a video. Results revealed that empathic reactions were moderately correlated with perceptions of animal welfare ( r = .53, p < .001) and mean empathic responses were higher for free choice handling and empathic messaging videos versus traditional handling and messaging. Programming recommendations are discussed that can improve visitors’ perceptions of animal care and elicit strong empathic reactions.

Providing Humans With Practical, Best Practise Handling Guidelines During Human-Cat Interactions Increases Cats' Affiliative Behaviour and Reduces Aggression and Signs of Conflict

The importance of animals' experiences and associated comfort during Human-Animal Interactions (HAI), and particularly Animal Assisted Interventions (AAI), are increasingly recognised. However, there remains a paucity of published research, particularly concerning less formal but frequent HAIs to which companion animals are typically exposed, such as stroking or petting. Additionally, few practical evidence-based guides to facilitate humans' optimal animal handling and interaction in these contexts exist. A simple set of Human-Cat Interaction (HCI) guidelines were therefore created, with the aim to enhance domestic cats' comfort during generic HCI contexts. Based around a “CAT” acronym, guidelines focused on providing the cat with choice and control (“C”), paying attention (“A”) to the cats' behaviour and body language and limiting touch (“T”), primarily to their temporal regions. Guidelines were presented to human participants during a brief training intervention, and guideline efficacy was subsequently assessed. Domestic cats available for rehoming at Battersea Dogs and Cats Home, UK (n = 100) were filmed during interactions with novel members of the public (n = 120). Cats were exposed to a maximum of six, 5-min interaction sessions, balanced across “control” (interactions with humans pre-training) and “intervention” conditions (interactions with humans post-training). For each observation, cat behaviour and posture were coded and humans' cat-directed behaviour rated on the degree to which it reflected best practise principles. Data were extracted from a total of 535 observations and average human interaction ratings and cat behaviour values compared between control and intervention conditions via paired Wilcoxon tests. Compared to the control, humans' interaction styles were rated as significantly more closely aligned with best-practise principles in the intervention condition. Cats also displayed significantly greater frequencies and/or durations of affiliative and positively-valenced behaviours in the intervention. In contrast, cats in the control displayed significantly greater frequencies of human-directed aggression, in addition to greater frequencies and/or durations of behaviours associated with conflict and negative valence. Results demonstrate the positive impact of practical interaction guidelines on cats' social behaviour and comfort during HCI, with the potential to improve cats' general experiences during interactions, reduce human-directed aggression and ultimately improve cat-human relationships.

Habituation Protocols Improve Behavioral and Physiological Responses of Beef Cattle Exposed to Students in an Animal Handling Class

Our objective was to determine the impact of different habituation protocols on beef cattle behavior, physiology, and temperament in response to human handling. Beef heifers were exposed to three habituation strategies: (1) tactile stimulation (brushing) in the working chute for seven consecutive days (STI; n = 18); (2) passage through the working chute for seven consecutive days (CHU; n = 19) and; (3) no habituation (CON; n = 19). Individual heifer respiratory rate (RR; n/min), internal vaginal temperature (VAGT; °C), and blood cortisol were measured. Further, behavior parameters were observed to generate a behavior score, and heifer interaction with students and their behavioral responses were recorded. Habituation with STI and CHU resulted in improved numerical behavioral scores compared to CON, and greater (p ≤ 0.05) handling latencies. Vaginal temperature was decreased in STI compared to CHU and CONT (p ≤ 0.05). Cortisol concentration did not differ among treatments, but decreased (p ≤ 0.05) from the start of the experiment to 14 days after treatment initiation. Both habituation protocols showed benefits, but heifers that received the positive tactile stimulation in the chute had the greatest behavior improvements. Furthermore, these heifers responded more calmly during student-animal interactions in class, which is beneficial for the students’ and animals’ safety.

A Simulation Design of Immersive Virtual Reality for Animal Handling Training to Biomedical Sciences Undergraduates

Background: One area of biomedical research concerns is applying new treatments to cure human diseases, moving bench-side research to the bedside practice. While using animal models is crucial in the research process, researchers should strictly adhere to the moral 4R framework to protect animal welfare—replacement, reduction, refinement, and responsibility. Virtual reality (VR) applies computer technology to create a simulated environment, allowing players to immerse and interact with animated 3D contexts. We developed a virtual animal-holding simulator (ViSi) using immersive virtual reality technology for students studying in the undergraduate biomedical sciences programme. The specific objectives of the paper are to 1) describe the development of the VR courseware for animal training and 2) describe the learning experience among students.Method and Result: An evaluation of the courseware was conducted among Year one and two biomedical sciences students. Students who participated in ViSi responded positively about their involvement in the virtual environment experience and their concentration on the assigned task.Discussion: ViSi is a reliable simulation technology that can train animal handling skills, which replaces real animals, while learners’ multi-cognition could still be enhanced with simulation training. Thus, the impact of immersive VR technology integrated into skills training is promising, although few technical problems are to be resolved.

Effect of illumination level [18F]FDG-PET brain uptake in free moving mice

In both clinical and preclinical scenarios, 2-deoxy-2[18F]fluoro-D-glucose ([18F]FDG) is the radiotracer most widely used to study brain glucose metabolism with positron emission tomography (PET). In clinical practice, there is a worldwide standardized protocol for preparing patients for [18F]FDG-PET studies, which specifies the room lighting. However, this standard is typically not observed in the preclinical field, although it is well known that animal handling affects the biodistribution of [18F]FDG. The present study aimed to evaluate the effect of ambient lighting on brain [18F]FDG uptake in mice. Two [18F]FDG-PET studies were performed on each animal, one in light and one in dark conditions. Thermal video recordings were acquired to analyse animal motor activity in both conditions. [18F]FDG-PET images were analysed with the Statistical Parametric Mapping method. The results showed that [18F]FDG uptake is higher in darkness than in light condition in mouse nucleus accumbens, hippocampus, midbrain, hindbrain, and cerebellum. The SPM analysis also showed an interaction between the illumination condition and the sex of the animal. Mouse activity was significantly different (p = 0.01) between light conditions (632 ± 215 s of movement) and dark conditions (989 ± 200 s), without significant effect of sex (p = 0.416). We concluded that room illumination conditions during [18F]FDG uptake in mice affected the brain [18F]FDG biodistribution. Therefore, we highlight the importance to control this factor to ensure more reliable and reproducible mouse brain [18F]FDG-PET results.