Elsevier

Journal of Veterinary Behavior

Volume 9, Issue 5, September–October 2014, Pages 215-221
Journal of Veterinary Behavior

Research
The effect of a pressure wrap (ThunderShirt®) on heart rate and behavior in canines diagnosed with anxiety disorder

https://doi.org/10.1016/j.jveb.2014.06.007Get rights and content

Abstract

The effect of moderate-to-deep pressure on soft tissue has been studied in both humans and nonhuman animals with positive results shown in reducing anxiety and promoting relaxation. Canine anxiety disorders are often treated with medications and behavior modification programming. Pressure wraps are sometimes used to treat canine anxiety, but the effects of this investigation have not been rigorously investigated. The aims of this study were to investigate the use of a pressure wrap (ThunderShirt®; ThunderWorks, Durham, NC) on heart rate and behavior in dogs diagnosed with an anxiety disorder. Subjects were 90 dogs (39 males and 51 females) that were diagnosed with Separation Anxiety or Generalized Anxiety Disorder. Dogs were randomly assigned to 1 of the 3 groups, namely Experimental Group 1 (dogs wore the ThunderShirt® per manufacturer's recommendations), Experimental Group 2 (dogs wore the ThunderShirt® loosely without pressure), and Control Group (dogs had no specific treatment). Average and maximum heart rates were measured at baseline and after 15 minutes alone in the kennel. Dogs were video-recorded and analysis completed for 12 behaviors, namely pacing, panting, yawning, tongue-flicking, drooling, elimination, barking, stress whining, howling, licking, door orientation, and calmness. The results were as follows: Dogs in Experimental Group 1 showed significantly less increase from baseline in average heart rate than the Control Group dogs (P < 0.001) and dogs in Experimental Group 2 (P < 0.001). Dogs in Experimental Group 1did not differ significantly from Control Group dogs in maximum heart rate when all dogs were considered, but did differ significantly from the Control Group (P = 0.04) when only those dogs not currently on anxiety medication were considered. There were no statistically significant differences among groups on behavioral outcomes, except that the dogs in the Control Group were significantly more likely to orient toward the door than the dogs in both Experimental Groups 1 (OR = 7.46, P = 0.01) and 2 (OR = 4.42, P = 0.04). Dogs in the Experimental Group 1 presented a trend of less tongue-flicking (P = 0.06) and yawning (P = 0.07) stress reduction behaviors when compared with the other 2 groups. More research should be conducted with the ThunderShirt® on behavioral outcomes. The ThunderShirt® can be used with behavior modification programming and medication as an adjunct treatment option to assist dogs diagnosed with anxiety disorder to reduce heart rate.

Introduction

Canine anxiety disorders are common behavior problems seen in veterinary clinics and hospitals across the United States. Treatments for these disorders incorporate medication, behavior modification programs, and alternative techniques. One technique, moderate-to-deep pressure, has been used in humans and animals to reduce tension and anxiety (Diego and Field, 2009, Edelson et al., 1999, Grandin, 1992). The research on moderate pressure massage in humans showed enhanced growth and development in infants as well as stress reduction in adults (Field et al., 2010). The use of pressure to calm animals and reduce stress has been documented in a number of studies (Grandin, 1992, Williams and Borchelt, 2003).

Early research, examining the use of pressure applied to a pig's lateral sides of the body while in a V-shaped trough, showed that pressure promoted relaxation and sleep in the animal (Grandin et al., 1989). Other livestock animals such as cattle had reactions to being restrained in a squeeze chute that were similar to human reactions in a squeeze machine. The cattle presented calm behavior after feeling the pressure from being in the squeeze chute (Grandin, 1992).

Although the use of pressure has been studied in livestock animals, there has been minimal research on the use of pressure to reduce anxiety and stress in canines. Genetic predisposition to display anxious behaviors is more obvious in prey species, where escape behavior is essential to survive threatening situations, than it is in predatory species, like canines.

The research conducted on the use of pressure in canines had small sample sizes. One study examined the use of pressure with 3 aggressive Great Danes (Williams & Borchelt, 2003). Each animal was individually restrained in a large wooden box. Approximately 275 kg of triple-cleaned oats were poured over the animal's body to completely immobilize it in a standing position while keeping the head and neck uncovered. Each dog was exposed to a stimulus to which they were reactive (either a human or another dog), with increasing intensity. Each of the dog's aggressive behaviors diminished rapidly during the restraint and resulted in presentation of calm behavior during the highest stimulus intensity (Williams & Borchelt, 2003). The researchers noted a reduced heart rate reading compared with baseline measurement and felt that tactile pressure may be an important tool in behavior modification (Williams et al., 2003).

Cottam and Dodman (2009) examined the use of a cape on 23 dogs that were thunder-phobic. The dogs were randomly assigned to an experimental and control group, with the experimental group dogs placed in a Storm Defender Cape (Fairfield, Ohio) during 4 different thunderstorm periods. The Storm Defender Cape is a wrap that has metal-lined fabric to prevent static charges that dogs may experience during a thunderstorm. The control dogs wore a non-antistatic cape during the 4 different thunderstorm periods. Researchers used owner reports (the owners were not blinded to the study) on how the dogs presented during the thunderstorm looking at specific behavior signs while wearing the cape. Owners completed a 12-question survey, and responses were scored examining the severity of behaviors associated with thunderstorm phobia. The use of both cape types was associated with a statistically significant decrease in median anxiety scores from baseline scores. After the cape was used on 4 occasions, the median anxiety score of the Storm Defender group decreased by 63% from baseline and the non-antistatic cape group's median anxiety score decreased by 36% from baseline. Owners in both groups indicated that their dogs displayed significantly less hiding behavior by the fourth use of the cape. Results from this study indicated the use of a form-fitting cape could be therapeutic in treating canine thunderstorm phobia (Cottam & Dodman, 2009).

Cottam et al. (2013) studied effects of the Anxiety Wrap (Bridgeport, Connecticut) for dogs with thunderstorm phobia. The Anxiety Wrap is marketed as a pressure wrap that uses gentle, constant pressure to relieve stress and end/lessen fear in these dogs. This study examined 18 dogs and used owner-reported scores related to use of the Anxiety Wrap during thunderstorm activity. The mean anxiety scores on the fifth use of the Anxiety Wrap were 47% lower than the mean anxiety score that was generated before the use of the Anxiety Wrap, a statistically significant finding (Cottam et al., 2013).

The aim of the present study was to determine whether there was an effect of a pressure wrap (ThunderShirt®; ThunderWorks, Durham, NC) on heart rate and behavior in canines diagnosed with an anxiety disorder.

Section snippets

Animals

A sample of 90 dogs (aged older than 6 months) diagnosed with anxiety (Separation Anxiety [n = 50] or Generalized Anxiety Disorder [n = 40]) (Overall, 2013, APA, 2013) by a veterinarian or applied animal behaviorist was referred from veterinary clinics and hospitals along the Front Range of Colorado. There were no breed restrictions for this study. Small, medium, and large breed dogs (purebreds and mixes) were used from the following categories: Terrier, Herding, Toy, Working, Sporting,

Results

Table 2 provides distributional information about the sample by treatment condition. The mean ages of the dogs were 74.8 months (standard deviation [SD] = 43.9), 71.5 months (SD = 40.2), and 53.2 months (SD = 32.7) for Experimental Group 1, Experimental Group 2, and the Control Group, respectively.

Examination of the treatment × time interaction effect in the ANCOVA (Table 3), using experimental group membership as the between-subject factor and age in months and anxiety medication status as the control

Discussion

The purpose of this study was to address whether the pressure provided by a ThunderShirt® had an effect on canines diagnosed with anxiety disorder. This study examined dogs from multiple breed groups who had been diagnosed with Separation Anxiety or Generalized Anxiety Disorder. Dogs with these diagnoses showed various anxiety signs and expressed these signs in varying degrees.

A model of animal stress begins in the central nervous system after an organism perceives a threat or potential threat

Conclusion

Results from this study showed that the dogs that wore the ThunderShirt® to manufacturer's specifications had lowered heart rate, decreased visual orientation toward the door (looking for their owner), as well as trending toward reduced yawning and tongue-flicking stress behaviors. More research, however, is needed on the use of a pressure wrap, and specifically the potential effect a ThunderShirt® may have on behavioral signs of anxiety in canines. The results of the present study suggest that

Acknowledgments

The authors would like to thank those who helped bring this research project to completion including the Dog Days Training Center Staff, namely Shantel Southwick, Kara Godebu, and Adam Shapiro. They would also like to thank the owners and their dogs that experienced anxiety while collecting data, in an attempt to consider alternative treatment options for canine anxiety disorder.

References (29)

  • APA

    Diagnostic and statistical manual of mental disorders

    (2000)
  • APA

    Diagnostic and statistical manual of mental disorders

    (2013)
  • S. Blairs et al.

    The clinical application of deep touch pressure with a man with autism presenting with severe anxiety and challenging behaviour. Brit

    J. Learn. Disabil.

    (2007)
  • J. Cohen

    Statistical Power Analysis for the Behavioral Sciences

    (1988)
  • Cited by (19)

    • At the heart of a dog's veterinary experience: Heart rate responses in dogs vary across a standard physical examination

      2022, Journal of Veterinary Behavior
      Citation Excerpt :

      A Polar® M430 Watch and H10 chest strap (Polar Electro, Kempele, Finland) was used to collect and record the HR data from each dog. Human Polar® HR devices have been validated against electro-cardiograms (ECG) in dogs previously (Jonckheer-Sheehy et al., 2012; Essner et al., 2013), and more recently used without validation to ECG (King et al., 2014). The data was exported from the online Polar® Flow portal to Microsoft Excel 2016 (Microsoft Corporation, WA, USA) for analysis.

    • Fearful Fido: Investigating dog experience in the veterinary context in an effort to reduce distress

      2019, Applied Animal Behaviour Science
      Citation Excerpt :

      Note, many recommendations for strategies to reduce stress are found in reviews (like Lloyd (2017)), however evidence for their efficacy within a veterinary clinic is minimal. For instance, King et al. (2014) found anxious dogs had significantly lower average heart rate and a lower increase in heart rate for dogs wearing a Thundershirt® as per its instructions for use in comparison to those wearing a loose Thundershirt® or no wrap. However, the test was conducted in a training facility, measuring the effect of isolation on the dog where participants had already been diagnosed with Generalised Anxiety Disorder or Separation Anxiety.

    • Using an owner-based questionnaire to phenotype dogs with separation-related distress: Do owners know what their dogs do when they are absent?

      2018, Journal of Veterinary Behavior: Clinical Applications and Research
      Citation Excerpt :

      The most common signs reported by owners are vocalization, house soiling, and destruction. Less commonly recognized signs are pacing, restlessness, withdrawal, inactivity, salivation, whimpering, vomiting, diarrhea, hiding, immobility, trembling, self-trauma, licking, yawning, tongue-flicking, body language (ears back, paw up, and tail down), and orientation toward environment (Overall et al., 2001; Cannas et al., 2014; King et al., 2014). Although the behavioral signs of distress are nonspecific, it is possible to benchmark and quantify them (Overall et al., 2016).

    • Dynamic changes in ear temperature in relation to separation distress in dogs

      2016, Physiology and Behavior
      Citation Excerpt :

      Evidence from other physiological measures (heart rate, cortisol) has similarly shown that separation in an unfamiliar room constitutes a stressful experience for pet dogs [33,44,49]. Apart from an initial increase in heart rate during the first separation compared to resting heart rate at baseline, [33] and [44] found that social isolation was associated with a reduction in heart rate compared to when a person was present (but see [43]). This could be explained by dogs' higher activity during the person's presence; or the lowered heart rate during isolation might reflect episodes of parasympathetic rebound to sympathetic activation [44] or a depressive like response.

    View all citing articles on Scopus
    View full text