Effect of environmental noise and music on dexmedetomidine-induced sedation in dogs

Effect of Classical Music on Depth of Sedation and Induction Propofol Requirements in Dogs

The main objective of this prospective, randomized, blind, cross-over experimental study was to evaluate the effect of classical music on the depth of sedation and propofol requirements for the induction of anaesthesia in dogs. Twenty dogs were involved, and each was subjected to three different treatments with a 3-month gap: Chopin music, Mozart music, and no music, via loudspeakers. The dogs were premedicated with acepromazine and butorphanol by intramuscular injection, and anaesthesia was induced using propofol intravenously. To compare the depth of sedation and propofol requirements for the induction of anaesthesia among the different treatments, we utilized non-parametric tests (Kruskal-Wallis test) for the depth of sedation due to a slight deviation from the normal distribution and parametric (ANOVA) for propofol requirements. When exposed to music (Chopin or Mozart), dogs exhibited deeper sedation and required less propofol for their intubation compared to the no-music treatment (p < 0.05). Exposure to classical music had a positive impact on the level of sedation, and more profound central nervous system depression seemed to contribute to approximately 20% lower propofol dose requirements for tracheal intubation. Therefore, classical music during the preoperative period appeared to exert a beneficial effect, at least when applying the specific pre-anaesthetic medications used in the present study.

Less is more? Ultra-low carbohydrate diet and working dogs' performance

New Zealand farm working dogs are supreme athletes that are crucial to agriculture in the region. The effects that low or high dietary carbohydrate (CHO) content might have on their interstitial glucose (IG) and activity during work are unknown. The goals of the study were to determine if the concentration of IG and delta-g (a measurement of activity) will be lower in dogs fed an ultra-low CHO high fat diet in comparison to dogs fed a high CHO low fat diet, and to determine if low concentrations of IG are followed by reduced physical activity. We hypothesized that feeding working farm dogs an ultra-low CHO diet would reduce their IG concentrations which in turn would reduce physical activity during work. We prospectively recruited 22 farm dogs from four farms. At each farm, dogs were randomized to one of two diets and had a month of dietary acclimation to their allocated diet. The macronutrient proportions as a percentage of metabolizable energy (%ME) for the high CHO low fat diet (Diet 1) were 23% protein, 25% fat, and 52% CHO, and for the ultra-low CHO high fat diet (Diet 2) 37% protein, 63% fat, and 1% CHO. Following the acclimation period, we continuously monitored IG concentrations with flash glucose monitoring devices, and delta-g using triaxial accelerometers for 96 h. Dogs fed Diet 2 had a lower area under the curve (±SE) for IG (AUC _{Diet 2} = 497 ± 4 mmol/L/96h, AUC _{Diet 1} = 590 ± 3 mmol/L/96h; P = 0.002) but a higher area under the curve (±SE) for delta-g (AUC _{Diet 2} = 104,122 ± 6,045 delta-g/96h, AUC _{Diet 1} = 80,904 ± 4,950 delta-g/96h; P< 0.001). Interstitial glucose concentrations increased as the activity level increased (P < 0.001) and were lower for Diet 2 within each activity level (P < 0.001). The overall incidence of low IG readings (< 3.5 mmol/L) was 119/3810 (3.12%), of which 110 (92.4%) readings occurred in the Diet 2 group (P = 0.001). In the Diet 2 group, 99/110 (90%) of the low IG events occurred during the resting period (19:00–06:00). We conclude that feeding Diet 2 (ultra-low CHO high fat diet) to working farm dogs was associated with increased delta-g despite decreased IG concentrations. Interstitial glucose concentrations were positively associated with dogs’ activity levels independent of diet. Lastly, events of low IG occurred at a low incidence and were predominantly seen between 19:00–06:00 in dogs fed the ultra-low CHO high fat diet.

Use of a Collar-Mounted Triaxial Accelerometer to Predict Speed and Gait in Dogs

Simple Summary

Accelerometers have been used for several years to monitor activity in free-moving dogs. The technique has particular utility for measuring the efficacy of treatments for osteoarthritis when changes to movement need to be monitored over extended periods. While collar-mounted accelerometer measures are precise, they are difficult to express in widely understood terms, such as gait or speed. This study aimed to determine whether measurements from a collar-mounted accelerometer made while a dog was on a treadmill could be converted to an estimate of speed or gait. We found that gait could be separated into two categories—walking and faster than walking (i.e., trot or canter)—but we could not further separate the non-walking gaits. Speed could be estimated but was inaccurate when speed exceeded 3 m/s. We conclude that collar-mounted accelerometers only allowing limited categorisation of activity are still of value for monitoring activity in dogs.

Abstract

Accelerometry has been used to measure treatment efficacy in dogs with osteoarthritis, although interpretation is difficult. Simplification of the output into speed or gait categories could simplify interpretation. We aimed to determine whether collar-mounted accelerometry could estimate the speed and categorise dogs’ gait on a treadmill. Eight Huntaway dogs were fitted with a triaxial accelerometer and then recorded using high-speed video on a treadmill at a slow and fast walk, trot, and canter. The accelerometer data (delta-G) was aligned with the video data and records of the treadmill speed and gait. Mixed linear and logistic regression models that included delta-G and a term accounting for the dogs’ skeletal sizes were used to predict speed and gait, respectively, from the accelerometer signal. Gait could be categorised (pseudo-R2 = 0.87) into binary categories of walking and faster (trot or canter), but not into the separate faster gaits. The estimation of speed above 3 m/s was inaccurate, though it is not clear whether that inaccuracy was due to the sampling frequency of the particular device, or whether that is an inherent limitation of collar-mounted accelerometers in dogs. Thus, collar-mounted accelerometry can reliably categorise dogs’ gaits into two categories, but finer gait descriptions or speed estimates require individual dog modelling and validation. Nonetheless, this accelerometry method could improve the use of accelerometry to detect treatment effects in osteoarthritis by allowing the selection of periods of activity that are most affected by treatment.

Effects of Music Pitch and Tempo on the Behaviour of Kennelled Dogs

Simple Summary

Domestic dogs often live in confined environments for different reasons. These environments can be challenging for some dogs and this can lead to high levels of stress and arousal, which could affect welfare. Auditory enrichment has been shown to reduce arousal-related behaviours in dogs, and the aim of this study was to investigate if these effects are induced by particular characteristics of music such as tempo and pitch. The behaviour of 10 kennelled dogs was monitored in response to music tracks played with different characteristics (high pitch, low pitch, fast tempo and slow tempo), as well as white noise and a control. Low pitch tracks seemed to prompt behavioural changes by increasing the level of alertness of the dogs, potentially due to the association between low frequency vocalisations with agonistic contexts, making them more vigilant of their surroundings.

Abstract

Confinement can be stressful for some dogs and this can lead to behavioural issues and poor welfare. A key component of the stress response is behavioural arousal, characterised by increased alertness and sensory sensitivity. This makes behavioural observations a useful tool to assess stress, as they provide insight into an animal’s internal state. Auditory enrichment has been shown to reduce arousal-related behaviour in dogs, but it is not clear if specific characteristics of a music track, such as tempo and/or pitch, produce these effects. The aim of this study was to compare behavioural responses of dogs to music tracks played with different characteristics (high pitch, low pitch, fast tempo, and slow tempo), as well as white noise and a control. Pitch and tempo modifications were applied to ten piano music songs and the six treatments (four different treatment-song combinations, white noise, and control) were presented daily, for ten minutes each, to ten dogs over ten days. Behavioural changes seemed to be driven by low-pitch tracks, which increased the level of alertness of the dogs. These findings could be related to the Morton’s motivations-structural rules: harsh, low frequency vocalisations signal aggressive motivations in mammals. Dogs may have perceived low-pitch tracks as more unsettling and were therefore more active and alert when listening to them.

Effects of music on behavior and physiological stress response of domestic cats in a veterinary clinic

OBJECTIVES

Our objective was to determine if feline-specific music played in a veterinary clinical setting would promote lower cat stress scores (CSSs), lower mean handling scale scores (HSs) and reduced neutrophil:lymphocyte ratios (NLRs) in cats during physical examinations.

METHODS

Cats were exposed to one of three auditory stimuli tests - silence, classical music and cat-specific music - during three physical examinations 2 weeks apart. CSSs were recorded at pre- and post-auditory tests and during the examination period. The HSs were recorded at the physical examination period. The physiological stress was assessed via NLRs.

RESULTS

The pre-auditory test showed no difference in CSS between cats listening to silence, classical music and cat music. CSSs for post-auditory tests and examination periods were not significantly different between silence and classical music; however, CSSs were significantly decreased in cats listening to cat music vs silence and in cats listening to cat music vs classical music. HSs were not different in cats listening to silence vs classical music, but were significantly lower in cats listening to cat music vs silence and classical music. No difference was found in NLRs among all three auditory stimuli tests.

CONCLUSIONS AND RELEVANCE

Listening to cat-specific music prior to, and during, physical examination was associated with lower CSSs and lower HSs in cats, but had no effect on the physiological stress responses measured by NLRs. We conclude that cat-specific music may benefit cats by decreasing the stress levels and increasing the quality of care in veterinary clinical settings.

Musical Dogs: A Review of the Influence of Auditory Enrichment on Canine Health and Behavior

Simple Summary

Interest in the use of music therapy as a behavioral enrichment tool in veterinary medicine is growing. Indeed, an industry has formed around the development of ‘dog music’, which has been purposely designed to relax dogs. Despite enthusiastic uptake of the idea, there is little empirical evidence supporting the design of such tools. This article summarizes the scientific literature in this emerging domain. It notes that, as a general observation, animals appear less stressed or anxious when exposed to classical music than to control conditions. It also acknowledges that this field is relatively under-researched, and more rigorous studies must be conducted before species-specific recommendations can be made. Such studies must reflect individuals’ and species’ preferences for different genres and songs, taking care to avoid habituation.

Abstract

Music therapy yields many positive health outcomes in humans, but the effects of music on the health and welfare of nonhuman animals vary greatly with the type of music played, the ethology of the species, and the personality and learning history of individual animals. One context in which music therapy may be used to enhance animal welfare is to alleviate stress in domestic environments. Here, we review studies of the effects of music exposure on dogs as a case study for the implementation of music therapy in veterinary medicine. Nine reports of experimental testing for the therapeutic effects of music on dogs were found, with most of these studies focusing on changes in behavior. Overall, exposure to classical music appears to have a calming influence on dogs in stressful environments, with no additional benefit observed from any music purposely designed for dogs (specifically “Through a dog’s ear”). Given the cost effectiveness and ease of implementation, music therapy holds promise in veterinary medicine and animal welfare. However, to address precise research questions, further studies must use clearly defined characteristics of stimulus music in the experimental design, and consider the variability of each individual animal’s physical characteristics and past experience in the selection of candidates.

Preoperative calming effect of melatonin and its influence on propofol dose for anesthesia induction in healthy dogs

OBJECTIVE

To investigate the preoperative calming effect of melatonin and its influence on propofol dose for anesthesia induction in dogs.

STUDY DESIGN

Prospective, randomized, blinded, placebo-controlled clinical study.

ANIMALS

A total of 50 healthy, adult, client-owned dogs scheduled for elective surgery.

METHODS

Dogs were equally divided into treatment group M, which received 5 mg kg^-1 melatonin, and placebo-control group P (sucrose), both administered orally 2 hours prior to induction of anesthesia. Dogs were subjectively characterized and further designated as skeptical (group S; n = 18) or trustful (group T; n = 32). Behavior, calming effect and vital parameters (pulse rate, respiratory rate, blood pressure, rectal temperature) were evaluated before and after treatment. Propofol dose [mg kg^-1 intravenously (IV)] to allow endotracheal intubation and anesthesia induction quality was documented. Data were analyzed using a general linear model and Mann-Whitney U tests.

RESULTS

Dogs in group MS (n = 10) were calmer than those in group PS (n = 8) at 90 minutes after drug administration (p = 0.047). Group MT (n = 15) required less propofol (5.98 ± 0.96 mg kg^-1) than group PT (n = 17; 7.04 ± 1.82 mg kg^-1 IV; p = 0.048) and group MS (9.48 ± 3.22 mg kg^-1 IV; p = 0.007). Group PS required 7.69 ± 2.71 mg kg^-1 IV. Skeptical dogs showed more reactions during induction (p = 0.013). Vital parameters were within physiological ranges before and after treatment.

CONCLUSION AND CLINICAL RELEVANCE

Results showed that melatonin may be used to reduce propofol dose for anesthesia induction in trustful dogs. Skeptical dogs benefitted from the calming properties. Potentially, melatonin could be used to minimize the level of excitement before general anesthesia and to reduce the required propofol dose for induction.