Posts tagged International Animal Health Journal

Pet Acoustics Audiometric Study Reveals Patterns of Age-Related Hearing Loss

The cover of IAHJ magazine, featuring a horse and a dog, nose-to-nose. — **Published in** ***International Animal Health Journal*** (volume 10, issue 4)**, 2024.**

This study investigates the prevalence, progression, and characteristics of age-related hearing loss (ARHL) in domestic dogs and cats. Given the importance of auditory communication in these species, understanding ARHL's impact is crucial for enhancing animal welfare and owner-pet interactions.

Presbycusis, or age-related hearing loss, is a prevalent issue in dogs, usually beginning to impact them when they are between 8 to 10 years old. Initially, this condition manifests as a reduced capacity to hear sounds at mid to high frequencies, which can progressively worsen to total hearing loss. ARHL in cats generally begin to show signs around 8 to 12 years old as part of their ageing process. Our study examines the behavioural adaptations that accompany this sensory decline, such as increased reliance on other senses and altered responsiveness, often misconstrued as an enhancement in hearing. Through comprehensive testing, this research aims to delineate the patterns of ARHL in these animals, highlighting the importance of early detection and management. The findings are intended to enhance the understanding of ARHL in pets, thereby aiding in the improvement of care strategies for senior dogs and cats experiencing this natural age-related change.

Purpose of the Study

Age-related hearing loss in dogs and cats is an important area of study for several reasons.

Animal Welfare

As pets age, hearing loss can significantly impact their quality of life. It can lead to confusion, anxiety, and changes in behaviour, as these animals rely heavily on their auditory senses for communication and environmental awareness. Understanding and addressing hearing loss can help in providing better care for ageing pets.

Owner-Pet Relationship

Hearing loss in pets can affect their interaction with their owners. Pets with diminished hearing may not respond to verbal commands or react to their owners' presence, which can be distressing for both the pet and the owner. By understanding the progression and impact of hearing loss, owners can adapt their communication methods to maintain a strong bond with their pets.

Veterinary Care & Management

Knowledge about age- related hearing loss aids veterinarians in diagnosing and managing this condition more effectively. This can include providing guidance to pet owners on how to care for a pet with hearing loss and exploring potential treatments or interventions to slow down the progression of hearing loss.

Insight into Human Hearing Loss

Studying age-related hearing loss in animals can offer insights into similar conditions in humans. Dogs and cats have a relatively shorter lifespan, allowing for quicker observation of the progression of hearing loss. This can contribute valuable data to the broader field of auditory health research.

Preventive Health Strategies

Understanding the causes and risk factors of age-related hearing loss in pets can lead to the development of preventive strategies. This may include dietary recommendations, environmental modifications, or early detection techniques to help maintain hearing ability for as long as possible.

Breed-Specific Research

Certain breeds of dogs and cats may be more prone to hearing loss as they age. Research in this area can inform breeders and potential pet owners about the risks and help in making informed decisions regarding pet selection and breeding practices.

Consideration for Study Variables

Certain breeds of dogs and cats are more prone to hearing loss due to genetic predispositions, congenital issues, or breed-specific characteristics. It's important to note that while these breeds may have a higher risk, hearing loss can occur in any dog or cat, especially as they age. Here are some examples:

Dogs

Dalmatian (congenital deafness)
Australian Shepherd (linked to merle coat)
Cocker Spaniel (ear infections leading to hearing loss)
Jack Russell Terrier (associated with white coat)
West Highland White Terrier (related to white coat)
English Setter (piebald and speckled coat patterns)

Cats

White Cats with Blue Eyes (genetic predisposition to deafness)
Asian Breeds (e.g., Siamese, Burmese)

Materials and Methods

We conducted a cross-sectional study involving 2,977 dogs and 639 cats of various breeds and ages by veterinarians and pet owners.

Audiometric testing was used to assess hearing thresholds, and owners completed questionnaires about their pets' auditory behaviours. Data regarding the species (dog or cat) and age of the subjects are gathered to further understand the commonality of age-related hearing loss from global testing results.

The audiometric testing was innovated by Janet Marlow, a renowned Animal Sound Behaviourist and the Founder of Pet Acoustics, Inc., as a free digital home hearing test for evaluating pets. Accessible via PetAcoustics.com, the test begins with a simple online questionnaire, requiring basic details such as the pet's species, name and date of birth.

The core of the test involves exposing the pet to three levels of sound wave frequencies, including high-frequency, mid- frequency and low-frequency tones, primarily audible to animals. Various digital devices were used from smartphones to laptops. To assist human testers in the process, sounds as a secondary layer of each test, consist of a bat and a cricket (high sounds), monkey and crow (mid sounds), pig and frog, (low sounds) at frequencies discernible to humans. Participants are instructed to carefully observe their pet's reactions to these sounds, noting behaviours such as ear and head movements, changes in body posture, signs of surprise or confusion, or a lack of response.

These observed reactions can include but are not limited to ear twitching, head tilting, alert posturing, one ear folding back, both ears pointing forward, startled jumping, apparent confusion, leaving the area, or showing no visible reaction at all. This comprehensive approach aims to provide pet owners with a user-friendly yet insightful tool for assessing their pets' auditory health from the comfort of their home or clinic.

The Pet Hearing Test by Pet Acoustics is designed for veterinary and home use, and is available free from their website.

How to Use the Test

The hearing test progresses with a refined questionnaire designed to capture specific reactions to the sounds played.

After demonstrating high-frequency sound waves, pet owners are prompted to answer the following questions, providing clearer insights into their pet's auditory responses.

Did you observe a reaction from your pet to the bat sound?
Did you observe a reaction from your pet to the cricket sound?
Did your pet show no reaction to the sounds?

Following this, the test introduces mid-frequency sound waves, overlying the distinctive calls of a monkey and a crow. Participants are again asked to meticulously answer the questions of their pet’s reactions, focusing on the same set of physical responses observed earlier.

The final phase of the test evaluates responses to low-frequency sound waves, overlying sounds at a similar level to those of a pig and a frog. This comprehensive approach allows for a thorough assessment across a range of auditory frequencies.

Upon completion of the test, the results are promptly sent to the pet owner's email. These results provide valuable information that can be shared with a veterinarian or veterinary client, particularly if there are concerns about potential hearing loss. This efficient and user-friendly method offers a convenient way for pet owners to proactively monitor their pets' auditory health.

A screenshot of the application, showing the high frequency audio test. — A screenshot of the personalized Home Pet Hearing Test.

Canine Results

The canine testing result shows a decline in hearing from 1 year up to the age of 17.

However, in this chart, it becomes clear that there is an apparent spike in hearing abilities in elderly dogs but it is not what it seems. The chart reflects a typical decline in hearing as dogs age, but with a contradicting view of auditory enhancement piquing at approximately age 13. However, there are reasons why older dogs at this age might appear to hear better during the testing.

Canine Reactions by Age

2,977 Dogs tested

Compensatory Behavior

In senior dogs, certain sensory abilities, like vision, diminish and there's an increased reliance on other senses, notably hearing. This shift, often mistaken for improved hearing, is actually an optimised use of the hearing ability that remains. This is indicated during the time of testing among almost 3,000 dogs.

Selective Hearing

The data shows a trend where elderly dogs might demonstrate selective hearing, responding more to specific sounds in the test or voice commands by the owner. While this could be interpreted as improved hearing, it's likely indicative of a preference for certain familiar sounds like the sound response to a crow or a cricket.

Inconsistent Hearing Loss

A closer look at the chart reveals that hearing loss in elderly dogs is not uniform across all frequencies. They might retain sensitivity to some frequencies while losing it in others, showing a varied response to different sounds during the test.

Behavioral Changes with Age

The chart may highlight behavioral changes in aging dogs exhibiting greater alertness or reactivity to sounds, which could be misconstrued as better hearing. These behavioral shifts might show increased behavioral anxiety during the test.

Canine Data

2977 Dogs tested

Feline Results

The chart illustrates a steady decrease in the ability of cats to hear high, mid, and low frequencies up to around 9 to 10 years of age.

Interestingly, the data from cats aged 14 to 16 suggests an apparent improvement in hearing abilities overall. However, this observed increase during the test is likely not due to a literal enhancement in auditory function but rather a result of various adaptive behaviors and physiological changes captured at the time of the test.

Feline Reactions by Age

639 Cats tested

As cats grow older and possibly experience a reduction in other senses, such as vision, they often become more reliant on their hearing. This doesn't mean their hearing improves; rather, they are maximizing the use of their existing hearing capabilities. Age-related changes in behavior or health could also cause cats to react more to the test animal sounds and frequency waves, which might be misconstrued as improved hearing.

Selective hearing is another aspect observed in elderly cats, where they respond more to certain sounds or voices. Additionally, the progression of hearing loss in elderly cats is not always uniform, as seen in this chart, impacting various frequency ranges differently. This inconsistency can lead to the perception of fluctuating hearing abilities.

These elements, when considered together, help explain the perceived increase in hearing abilities in older cats, as indicated by the chart. It's important to recognize these factors as adaptation to the moment of testing rather than a true improvement in hearing.

Feline Data

639 Cats tested

Conclusion

Participating in a home pet hearing test offers several benefits for both pet professionals and pet owners.

Early Detection of Hearing Loss

Conducting regular hearing tests at home can help in the early detection of hearing loss in pets. Early detection is crucial for managing the condition effectively and ensuring the pet maintains a good quality of life.

Non-Invasive

Home tests are non-invasive and can be performed in a familiar and comfortable environment for the pet. This reduces stress and anxiety that pets might experience in a clinical setting.

Convenience and Cost-Effective

Home tests offer convenience as they can be done without the need to travel to a veterinary clinic or can be used by a smartphone at a veterinary exam.

Improved Communication & Care

Understanding a pet's hearing capabilities allows pet owners and professionals to better communicate with and care for them. It can help in modifying training techniques, environment adjustments, and daily interactions to accommodate the pet's needs.

Safety & Prevention

Identifying hearing issues can lead to preventive measures to ensure the safety of the pet. For example, a pet with hearing loss might need to be kept on a leash during walks to prevent accidents.

Enhanced Monitoring for Breed-Specific Risks

Some breeds are predisposed to hearing problems. Regular hearing tests can help in monitoring these breeds closely for any signs of hearing loss.

Data Collection for Research

Participation in such tests can contribute valuable data for veterinary research on pet hearing loss, which can lead to better diagnostic tools and treatments in the future.

Strengthening the Human-Pet Bond

Engaging in such care activities can strengthen the bond between pets and their owners. It shows commitment to the pet's well-being and can enhance the mutual trust and understanding between the pet and the owner.

Professional Development for Pet Professionals

For professionals, conducting these tests can enhance their skills in diagnosing and managing hearing issues in pets. It can also provide valuable insights for advising pet owners on best practices for caring for a pet with hearing loss.

Contributors

Janet Marlow

Founder and Sound Behaviorist, Pet Acoustics

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Clinical Studies, Cats, DogsJanet MarlowFebruary 4, 2024International Animal Health Journal, Pet Hearing Test

Biometric Study Proves Canine-Specific Music Mitigates Stress Levels

**Printed in** ***International Animal Health Journal*** (volume 9, issue 2)**, published in 2022.**

Canine behavioural stress is often triggered by their acute hearing to sounds in the environment. Dogs can hear from 67Hz to 45,000 Hz which is more than two times higher than human hearing which is 20Hz-20,000Hz. To modify behavioural stress in dogs, Janet Marlow, Founder of Pet Acoustics innovated a science-based music process specifically for canine, feline and equine acute hearing.

The benefits of this music in the canine listening environment has been proven in previous studies with results showing calm and a more balanced behaviour. To further understand the calming effects, this new study was initiated to analyse the biometric data of mostly small dog breeds in particular while listening to the species- specific designed music. Why a focus on small dog breeds? Behaviourally, small dog breeds show more fearful and anxious behaviours for various reasons: their comparative size creates a threatened and defensive posturing; owners tend to be overprotective, limiting social confidence; their sonic and vibrational environment triggers an intense physical response. For example, a dog may exhibit compulsive grooming by repeatedly licking or chewing at their skin and fur to help relieve their anxious feelings. Therefore, determining the calming effects of canine- specific music on a biometric level for small dog breeds can provide a tool that promotes calm behavior for a longer, healthier life.

Purpose of Study

The study began in January, 2022, with the purpose of documenting each dog’s biological responses when the canine music was playing and comparatively, when the music was not playing. The music was disbursed by the pre-loaded, Pet Acoustics Pet Tunes Bluetooth® speaker and placed near the dog. The canines for the test were provided by Ron Pia, canine behaviourist in Australia, who facilitated the study. The dogs were volunteered by their owners to participate in the study, with a stay over in a home where the testing took place. Each dog’s daily schedule included rest, walks and play activity. Twenty dogs were monitored, one by one, of different ages and breeds which included: West Highland Terrier, Beagle, Long Haired Chihuahua, Cavalier King Charles Spaniel, French Bulldog, Lagotto Romagnolo, Pomeranian, English Springer Spaniel, Border Collie, Labradoodle, Poodle and a German Shepherd. The ages ranged from six months to twelve years.

Each dog’s vital signs were documented in real time by wearing the Petpace smart collar. The Petpace collar measured each dog’s pulse rate, HRV rate and activity levels with the music playing and without the music playing.

The purpose of this study is to support the hypothesis that canine-specific music induces a physiological and behavioral calmer state in small dog breeds as well as larger dog breeds, helping them modify stress-triggered behavior for better health and balance. The twenty dogs in this study were male and female, neutered and not neutered, different sized breeds and different ages.

The four month biometric study monitored twenty varying small and larger dog breeds of different ages by measuring their pulse rate, HRV rate, and activity level determining the effects of the music to mitigate anxiety. Each dog's vital signs and behavior patterns were collected by wearing the Petpace smart collar.

Pulse

Pulse, or heart rate, is the measurement of the number of times a pet’s heart beats per minute. Heart rate is one of the most important vital signs caregivers can measure for a pet. When the heart rate is measured peripherally by palpating or sensing the pulse in a limb it is called pulse. The job of the heart is to pump blood throughout the body, supplying oxygen to the cells. A pet’s heart rate is controlled by a sophisticated mechanism that takes into account the oxygen demand from the cells and makes sure the heart is able to provide it. For example, when a dog runs, its muscles work hard and consume a lot of oxygen. Therefore, the heart must work faster to supply the demand. Fear is another condition that is associated with increased heart rate in pets. When a pet (or a human) is afraid, the body gets ready for a fight or flight situation, and prepares for the anticipated increase in demand for oxygen.

Heart Rate Variability (HRV)

Heart Rate Variability (HRV) is a statistical analysis of the small variations in time intervals between heartbeats. The variations are innate and normal physiological phenomena. Studies have shown that changes in HRV are associated with a wide range of diseases as well as pain, stress, and obesity. HRV is recognised as a marker for autonomic nervous system activity. The autonomic (parasympathetic and sympathetic) nervous systems as well as hormonal factors provide the main input to the heart’s pacemaker, and the beat-to-beat interval variability is a reflection of the balance between these two. High HRV indicates a good fitness level and a healthy heart and nervous system. Low HRV is associated with stress, pain, heart disease and other pathologies.

Activity Score

Activity Score is a calculated value that provides a quantitative representation of a pet's activity during the selected time range. It is based on summarising all the separate activity readings and producing a total value for the pet's overall activity. What is known is that monitoring and analysing activity patterns and levels can provide valuable medical insights. For example, a decline in activity levels may indicate the development of a disease causing pain or weakness. Activity is also affected by stress levels but this effect is more complex. Some dogs respond to stress by excessive barking, pacing or shaking, while others respond by hiding or loss of appetite. The study evaluated each dog’s activity levels.

Materials

Pet Acoustics and Petpace

There were two catalysts used for the study; the Pet Acoustics canine-specific music and the Petpace smart collar. Each of the twenty dogs wore the PetPace collar for approximately six hours within a twenty-four hour period during various activities. Biometric data was collected by an array of sensors in the collar device. The music was played for three hours. After this time, the music was turned off for three hours in the area of the collared dog for comparison. During the six hour session with the collar, the data was collected in real time and could be seen on a cloud-based analysis engine program provided by Petpace.

Pet Acoustics Canine-Specific Music

The canine-specific music used in the study is a science- based process with measurable and repeatable results to calm behavioral stress in dogs. Different from music for human hearing, the instruments, frequency and decibel levels are digitally modified in original compositions to accommodate the comfort range of canine acute hearing. Species-specific music is a copyrighted, proprietary process innovated in 1997 by Janet Marlow, sound behaviourist and composer for Pet Acoustics.

Janet Marlow, founder of Pet Acoustics and Sound Behaviorist, at the Litchfield Veterinary Clinic.

Methods

After the first dog’s testing was completed, the collar was removed and placed on the next dog visiting the testing site. The same method was done with each of the other dogs collecting the biometric data every two minutes during the sessions. Each dog was tested with half the session without the music playing and then with the music playing.

When the music wasn’t playing, each dog heard and responded to the natural sounds of home life as well as several daily walks and playtime. During the four month period however, there were sounds of passing intense thunderstorms with lightning. Within the testing home of the twenty dogs, there were multiple dogs in the same environment.

Results

When looking at the aggregated data for all the dogs that participated in the study, we can see that the median pulse rate was lower, the median HRV was higher, and the median activity score was slightly lower when the dogs were exposed to the calming music compared to these values when no music was being played.

Pulse

Pulse rate decreased in response to music. The average of median pulse rates was 5.9% lower during times when the dogs were exposed to the music (57.95) compared to times when the dogs were not exposed to the music (61.58).

HRV

Music caused the HRV to increase (high HRV indicates lower stress level). In this study, the overall average of median HRVs was 1.3% higher during times when the dogs were exposed to the music (11.63) compared to times when the dogs were not exposed to the music (11.48).

Activity

The activity score value showed varying results. The median activity score was lower for 10 dogs out of the 20 that participated in the study, and higher for the other 10 dogs. The total average of median Activity Scores was 3.5% lower during times when the dogs were exposed to the music (31.84) compared to times when the dogs were not exposed to the music (32.98).

Conclusions

The Pet Acoustics music that was tested in this study caused physiological and behavioural changes indicating a calmer state for dogs. The pulse rate was lower and HRV was higher in response to music, both being physiological changes associated with a calmer state (lower relative sympathetic tone, or a weaker “fight or flight” state).

All these findings supported the hypothesis of a calming effect as a result of the dogs listening to the music shown by the biometric data. The most significant finding was the HRV, which showed a considerable elevation from baseline, even more than what we see with the pulse. HRV was lower when the sympathetic tone (fight or flight mode) was higher, and vice versa. Therefore, a calm animal should have a higher HRV.

Benefits for Canine Welfare

The results of the study proved that canine-specific music modifies stress behaviours in small dogs. The stress scores were significantly lower in dogs listening to the music as compared with no music. There were no significant differences when comparing the sex, age or breed of the dogs, whether they were neutered or not and whether they were outdoors or indoors, all responded positively to the music.

Therefore, small dog breeds inclination for more intense stress responses to their environment can be successfully mitigated by the use of canine-specific music regardless of the owners consistency of training or environment. Additionally, this study showed larger sized dogs have the same ratio of biometric calming response to the music.

Applications and Benefits

For veterinarians – When playing Pet Acoustics canine- calming music, there is a reduction in stress which allows the team to conduct better physical examinations and take more accurate vitals. Broadcasting this music in the waiting rooms of veterinary clinics can also help to ease the anxiety of waiting dogs.

More Applications

Modify stress for separation anxiety
Modify stress in animal shelters
Calmer response to thunderstorms and firework events Less stressful breeding and birthing
Use for post-surgery healing
Use for travel anxiety

Contributors

Janet Marlow

Founder and Sound Behaviorist, Pet Acoustics

Dr. Asaf Dagan

Chief Veterinary Scientist, PetPace

Ron Pia

Founder, The Pet Calmer

Feline behavioural stress is triggered by their acute sensitivity to sounds in the environment. Cats can hear from 40Hz to 85,000 Hz, which is more than three times higher than human hearing, at 20Hz-20,000Hz. To modify behavioural stress in cats, Janet Marlow, Founder of Pet Acoustics innovated science-based music designed for feline acute hearing.

The benefits of this calming music has been repeatable and observable since its use for cats starting in 1997. To further understand the calming effects of this music, a study was initiated to analyse the biometrics of cats while listening to the music. The three-month clinical study monitored nine adult cats measuring their pulse rates, HRV, and activity levels determining the effects of the music. Each cat's vital signs and behaviour patterns were continuously collected in real time wearing a PetPace smart collar. By having a deeper understanding of how feline-specific music diminishes stress in cats on a biometric level can further define its use for feline welfare.

Purpose of Study

The clinical study began in October of 2020 with the purpose of documenting the biometric effects of feline-specific calming music. Two cat breeders volunteered their multiple cat homes in Southern Australia for the study. The nine adult cats monitored were different breeds, which included Abyssinian, American Shorthair Black Silver Classic Tabby, Domestic mixed, Russian Blue and Selkirk Rex Shorthair. Their ages ranged from two years to twelve years.

Each cat’s vital signs of their pulse, Heart Rate Variability (HRV) and activity were recorded using a PetPace smart collar for cats.

The purpose of this study is to support the hypothesis that Pet Acoustics feline calming music induces a physiological and behavioural calmer state in cats. By measuring the pulse, HRV and activity scores, we can show the physiological and behavioural responses to the music. The nine adult cats were male and female, neutered and not neutered, different breeds and different ages.

Monitoring feline vitals (pulse, HRV and activity) while playing Pet Acoustics species-specific music.

Pulse

Pulse, or heart rate, is the measurement of the number of times a pet’s heart beats per minute. Heart rate is one of the most important vital signs caregivers can measure for your pet. When the heart rate is measured peripherally by palpating or sensing the pulse in a limb, it is called pulse. The job of the heart is to pump blood throughout the body, supplying oxygen to the cells. Your pet’s heart rate is controlled by a sophisticated mechanism that takes into account the oxygen demand from the cells and makes sure the heart is able to provide it. For example, when a dog runs, its muscles work hard and consume a lot of oxygen. Therefore, the heart must work faster to supply the demand. Fear is another condition that is associated with increased heart rate in pets. When a pet (or a human) is afraid, the body gets ready for a fight- or-flight situation and prepares for the anticipated increase in demand for oxygen.

Heart Rate Variability (HRV)

Heart rate variability (HRV) is a statistical analysis of the small variations in time intervals between heartbeats. The variations are innate and normal physiological phenomena. Studies have shown that changes in HRV are associated with a wide range of diseases as well as pain, stress, and obesity. HRV is recognised as a marker for autonomic nervous system activity. The autonomic (parasympathetic and sympathetic) nervous systems as well as hormonal factors provide the main input to the heart’s pacemaker, and the beat-to-beat interval variability is a reflection of the balance between these two. High HRV indicates a good fitness level and a healthy heart and nervous system. Low HRV is associated with stress, pain, heart disease and other pathologies.

Activity Score

Activity score is a calculated value that provides a quantitative representation of a pet's activity during the selected time range. It is based on summarising all the separate activity readings and producing a total value for the pet's overall activity. What is known is that monitoring and analysing activity patterns and levels can provide valuable medical insights. For example, a decline in activity levels may indicate the development of a disease-causing pain or weakness. Activity is also affected by stress levels, but this effect is more complex. Some cats respond to stress by being restless and vocal, while others respond by freezing and hiding. The study evaluated each cat’s activity levels.

Materials and Methods

There were two catalysts used for the study: the PetPace smart collar and the Pet Acoustics feline calming music. Each of the nine adult cats wore the PetPace collar over a four-day period. Biometric data was collected by an array of sensors in the collar for twelve to twenty-four hours without the music playing. After this time period, the Pet Acoustics feline calming music was turned on for twelve to twenty-four hours in the area of the collared cat. The music was broadcast from a portable Pet Acoustics Pet Tunes speaker which is pre-loaded with the music on a micro SD card. The feline-specific music played continuously until it was turned off. During the listening session, the pulse rate, HRV and activity data was collected. The data occurred in real time and could be seen on a cloud- based analysis engine program.

The music is specific to the comfort hearing of cats which is within 60 to 80dB. Additionally, the music is modified by frequency content to stay within the frequency levels that do not trigger hypervigilant response. This proprietary process was innovated by Janet Marlow in 1997.

After the first cat’s testing was completed, the collar was removed and placed on the next cat. The same method was done with each of the other eight cats collecting the biometric data every fifteen minutes during the four-day period. Each cat was tested with half of the session with no music playing and then with the music playing.

When the music wasn’t playing, each cat heard and responded to the natural sounds of home life. During the three- month period, however, there were sounds of workmen and construction in the home and several intense thunderstorms. One cat travelled in a car in a crate. Within the two homes of the nine cats tested, there were multiple cats and a dog.

Music in the feline study was broadcast from a portable Pet Acoustics Pet Tunes Feline speaker.

Results

The pulse rate and the activity were lower as well as the HRV being higher when the cats were exposed to the calming music.

Pulse

The pulse rate was lower, and the distribution of results was narrower. The overall median pulse rate was 3.3% lower during times when the cats were exposed to the music (148) compared to times when the cats were not exposed to the music (153). Four of nine cats had a lower median pulse rate during music time. Moreover, the distribution of pulse readings during the music time was lower (range 101-216, delta 115) compared to the non-music times (range 89-232, delta 143).

Each point on the graph indicates a specific pulse measurement made by the collar. By moving the cursor over the point, one can see the actual reading and the time it was made. The line is a simple moving average of the pulse readings.

If the pulse rate is too high (tachycardia) or too slow (bradycardia) for the dog or cat’s activity level, an alert will be generated to have your pet examined by a veterinarian.

HRV

HRV is higher with music and the distribution of results is narrower. In this study, the overall median HRV was 4.6% higher during times when the cats were exposed to the music (9.48) compared to times when the cats were not exposed to the music (9.06). All cats had a higher median HRV during music time. The distribution of HRV readings during music time was lower (range 8.1-10.36, delta 2.26) compared to the no-music times (range 6.7-10.47, delta 3.77).

Each point on the graph is a statistical analysis of the small variations in time intervals between heartbeats. The variations are innate and normal physiological phenomena. Studies have shown that changes in HRV are associated with a wide range of diseases as well as pain, stress and obesity. High HRV indicates good fitness level and healthy heart and nervous system. Low HRV is associated with stress, pain, heart disease and other pathologies. There is no published reference range for HRV-VVTI. Based on preliminary analysis, we estimate that the following ranges apply for dogs:

>11.5 Normal
11.0-11.5 Suspicious
<11.0 Likely to indicate a health problem

The normal range for cats is not yet completely established. Values >9.5 are likely a deviation (decrease) from the typical values indicating a possible health problem or stress.

Activity

Activity score is a calculated value that provides a quantitative representation of a pet's activity during the selected time range. It is based on summarising all the separate activity readings and producing a total value for the pet's overall activity. The overall median activity score was 8.2% lower during times when the cats were exposed to the music (46.9) compared to times when the cats were not exposed to the music (51.1). All nine cats had a lower activity score during music time compared to no-music times.

This chart divides the pet’s activity intensity into four levels – resting, low, medium and high activity. Low activity helps identify pain from orthopedic problems, like joint disease, or general health issues causing fatigue and lethargy. High activity may be associated with restlessness, agitation, alertness and discomfort. Monitoring activity is useful when pets are recovering from trauma, surgery or disease, to ensure that they get the rest they need and gradually resume normal activity patterns.

Conclusions

The Pet Acoustics music that was tested in this study caused physiological and behavioural changes indicating a calmer state for cats. The activity levels of all the cats tested was lower. The overall pulse rate was lower and the distribution of the results was narrower. The HRV for all cats was higher with the music and the distribution of the results was narrower.

All these findings supported the hypothesis of a calming effect as a result of the cats listening to the music. The most significant finding was the HRV, which showed a considerable elevation from baseline, even more than what we see with the pulse. HRV was lower when the sympathetic tone (fight- or-flight mode) was higher, and vice versa. Therefore, a calm animal should have a higher HRV.

Benefits for Canine Welfare

The results of the Pet Acoustics study proved that feline- specific music modifies behaviours in cats. The stress scores were significantly lower in cats listening to the music as compared with no music. There were no significant differences when comparing the sex, age or breed of the cats, whether they were neutered or not and whether they were outdoor or indoor cats, all responded positively to the music.

For veterinarians, when listening to the Pet Acoustics feline calming music there is a reduction in stress, which allows the team to conduct better physical examinations and take more accurate vitals. Broadcasting this music in the waiting rooms of veterinary clinics helps to ease the anxiety of waiting cats.

Applications and Benefits

Calms behaviours in cat shelters
Relieves muscle tension during grooming sessions
Masks agitating sounds of thunderstorm and firework
Events
Calms behaviour for breeding and birthing
Reduces stress introducing a newly adopted cat
Ideal for stress management for post-surgery healing
Diminishes crate travel anxiety
Lessens nocturnal activity

Pet Acoustics music helping to calm an anxious cat patient at the Litchfield Veterinary Clinic.

Contributors

Janet Marlow

Founder and Sound Behaviorist, Pet Acoustics

At the beginning of training routine, young racehorses are exposed to stressful stimuli. The aim of the study was to evaluate the influence of a relaxing massage which the horses received in the stable, and the influence of music piped into the stable, on the long- lasting stress level of the horses. 120 Purebred Arabian horses were studied. They were examined during the first racing season, which lasted for six months.

At the beginning of the study, the horses were 28–31 months old. The horses were brought to S!uÊewiec Horse Race Track (Warsaw, Poland) from their familiar studs and were randomly assigned to music (n=48), massage (n=48), or control (n=24) groups. All horses were regularly trained and competed in official races. Once a month, saliva samples were collected from each horse to determine the cortisol concentration. Both music and massage resulted in significantly lower salivary cortisol concentration compared to the control treatment.

We see them move to music through Dressage routines. As riders, we partner with our rhythmic friends eliciting their tempos in two and three beats, walking, trotting and galloping, defining the equine species as one of nature’s musicians. The equine hearing range is higher than human hearing. Our human frequency hearing range is 20Hz to 20,000Hz. The frequency hearing range of a horse is 55Hz to 33,500Hz. In fact, horses and humans share the most closely related hearing ranges than any other mammals on the planet. A whisper in their ear from your voice or a personalised whistle from the barn to come in from the field is a significant part of the deep bond with our horses and strong connection through sound. This understanding has been an integral part of the research of Pet Acoustics Inc. with the innovation of a special speaker system that modifies sound disbursement for animal hearing and specifically designed science-based music for dogs, cats and horses by Janet Marlow, internationally recognised composer and Sound Behaviourist.

In 2015, a two-year study was initiated by Witold K#dzierski1, Iwona Janczarek, Anna Stachurska and Izabela Wilk of the Department of Biochemistry, University of Life Sciences in Lublin, Lublin, Poland Department of Horse Breeding and Use, University of Life Sciences in Lublin, Lublin, Poland. The study used the Pet Acoustics speaker and Janet Marlow’s equine specific music in the following study.

Introduction

Young Purebred Arabian horses in Poland are routinely submitted to race training. At the age of 2.5 years, they are moved from familiar studs to an unfamiliar race training centre. Much of the stimuli accumulated at the beginning of the training routine is associated with transport, change of residence, physical effort and participation in races, and can elicit chronic stress in horses (Alexander and Irvine 1998). Moreover, the commercialisation of racetracks alters the living conditions towards circumstances inconsistent with the biology of horses (MacTaggart et al. 2010). Keeping a racehorse in a box for most of the day, results in restricted freedom of movement (Henderson 2007). An unfamiliar environment, isolation, and short feed intake can also deepen the stress level (Waters et al. 2002). It is known that long- lasting stress has a negative influence on the organism. The factors generating stress in trained horses, however, can only be partially eliminated. Therefore, negative factors should be controlled and their effects should be mitigated (Evans 2003). Various relaxing methods may be used, e.g. free movement in the paddocks, massage and music. Massage promotes general body relaxation and increases the sense of an animal's well-being (Scott and Swenson 2009). In horses, the heart rate measured during and immediately after a massage was reduced, and improved behavioural responses were noted (McBride et al. 2004). Horses are generally sensitive to music. The most visible sign of the influence of music on horses is the horse’s ability to synchronise their movement to musical rhythm (Bregman et al. 2012). According to Carter and Greening (2012), the effect of the music on a horse’s behaviour depends on the music genre. Stachurska et al. (2015) showed that relaxation music positively affected the emotional state in racehorses. However, little is known how these kinds of relaxation methods reduce long-lasting stress in racehorses (Scott and Swenson 2009).

The most common approach used to evaluate the stress level in horses is measuring cortisol release (Peeters et al. 2010, Schmidt et al. 2010a, b). The cortisol is a natural glucocorticoid hormone synthesised by the adrenal cortex, which in turn, is stimulated by sympathetic nervous system activity. The main function of the hormone is to increase blood glucose level during effort and stressful conditions. In horses, the blood plasma cortisol concentration reflects not only the response to exertion (Desmecht et al. 1996, Nagata et al. 1999) but also the mental stress level (Cayado et al. 2006, Fazio et al. 2008). In recent years, in cortisol determination, more attention has been devoted to saliva sampling. This form of sampling is less stressful for the horse than blood sampling (Peeters et al. 2010, 2011). The level of the saliva cortisol correlates well with its level in the blood (van der Kolk 2001, Peeters et al. 2011, Bohak et al. 2013). The salivary cortisol concentration was successfully used as an indicator of the stress level in horses in response to stabling (Harewood 2005), road transport (Schmidt et al. 2010a, b) and exercise (K#dzierski et al. 2013, 2014a). A significant increase in the salivary cortisol concentration was stated in naïve horses during the initial training. The increase was particularly significant in response to mounting by a rider (Schmidt et al. 2010a, K#d- zierski et al. 2014b). Thus, measuring the cortisol concentration in saliva samples was assumed to be a useful marker of mental stress in horses.

The aim of the study was to evaluate the influence of a relaxation massage, and music piped into the stable, on the horse’s long-lasting stress level gauged with the salivary cortisol concentration.

Dr. Reuss attending to a horse with Pet Tunes Equine music.

Materials and Methods

This article presents data collected within a larger research project designed to determine the influence of chosen relaxation techniques on the emotional state of young racehorses. The study tested the hypothesis that relaxation techniques such as massage and music used over a long period of time, decrease the salivary cortisol concentration in racehorses.

Horses

In the study, 120 Purebred Arabian horses were examined over two years: 57 horses in the first year and 63 in the second year. All the horses participated in the study during their first racing season. Each horse was studied for six months, which covered the full race season for three-year old Purebred Arabian horses. At the beginning of the study, the horses were 28–31 months old. The horses were brought to S!uÊewiec Horse Race Track (Warsaw, Poland) from their familiar studs about three months earlier to acclimatise to the new conditions. After a month of acclimatisation, the horses began the initial training. On the first few days, they were bridled and saddled inside their boxes. Next, they were walked and trotted in an automated horse walker for 30 minutes a day. After that, the horses were mounted. The caretaker held the reins and another caretaker assisted the rider to first lay over the back of the horse and then to move to a sitting position in the saddle. This initial training lasted nine to twelve days, depending on the horse's behaviour. Finally, the riders walked and trotted the horses in a paddock for 30 minutes a day for about six weeks.

The horses were randomly divided into three groups: control group (n=24), music group which listened to music meant to be relaxing (n=48), and massage group (n=48) which regularly received a relaxing massage for about 30 minutes, three days a week. The only criterion of dividing the horses into the groups was that the groups were to include a similar number of mares and stallions. During the whole testing period, the horses were housed in four stables under comparable social and environmental conditions. Each horse was kept in a box stall measuring 3.5 m $ 4 m. Straw bedding allowed the horse to comfortably lie down. To reduce the influence of nonspecific factors on the animal’s emotional reaction, all the horses were fed the same diet according to dietary guidelines and cared for by the same caretakers in a manner which was typical for racehorses. This means that all

horses had equal exposure to all the caretakers. To minimise the influence of the year and stable factors, the experiment was arranged in a manner shown in Table 1. For the first year of the study, the massage was introduced in stables 1 and 2, and the music in stables 3 and 4. The schedule was revised in the second year of the study. The control group also continued in respective stables in the consecutive years.

Before the study, all of the horses were clinically sound according to a veterinarian. All the horses showed normal behaviour according to the trainer. Not all of the horses remained in training for the whole racing season because, in some cases, the owners decided to end their horse’s career before the end of the season. Thus, the number in the data for each month was lower than the number of horses included in a group, and amounted to 62.5%–89.6%.

Sound Behaviorist and Founder of Pet Acoustics, Janet Marlow.

Training and Racing

The experiment was performed according to the regular race-training schedule, and for two race seasons. The training sessions were performed for about one hour a day, six days a week. The riders saddled the horses then walked the horses for approximately 10 minutes as a warm-up exercise. The primary race training was conducted on the sand track. The speed and duration were individually adapted to the level of each horse’s performance. An exception was made for the measurement days. On the measurement days, each horse had to cover a distance of 1800m at a speed of 6.4m/s. After the exercise, the horses were put on an automatic horse walker for 45 minutes. At the end of the third month of the study, the horses started to compete in official races at least once a month. A day before and two days after the race, the horses were only given 60 minutes of exercise in the automatic walker. On those days, they were not examined. All persons included in the training and maintaining of the studied horses didn’t know the purpose of the study.

At the end of both race seasons, the horses’ performance was estimated with four parameters based on official race records: (1) number of races, in which a horse won; (2) prize per race, i.e. sum of prizes won to the number of races a horse took part; (3) success coefficient, i.e. sum of prizes won by a horse to sum of prizes won by all horses at the same age in respective race season; (4) general handicap, i.e. theoretical weight (in kg) a horse should carry in a race to equal the horse’s chance to win the race, with the chances of other horses at the same age.

**Figure 1** Salivary cortisol level determined at rest in studied groups of horses during following months of the training season (means ‡ SD). 1, 2, 3 ... = following months of the study; * = means in Control Group differ significantly in comparison to other groups; += mean in massage group is significantly different than in music group.

Listening to Music

For approximately five hours a day, the music group listened to music piped into their stalls. The music was played in the stable from 1 to 6 o’clock p.m. The music used was specifically composed and recorded by Janet Marlow, a specialist in the scientific use of music for animals. The rhythms and sound frequency of each composition were specifically composed to be within the sensitivity of the equine hearing range (Saslow 2002, Wells 2009). The relaxation music contained 10 tracks of equine-specific music, composed by Janet Marlow, Sound Behaviourist and Founder of Pet Acoustics. The music was heard in the stable through a special sound speaker device:

My Pet Speaker®, Pet Acoustic Inc, Connecticut, USA) also designed to be within the range of horse-hearing. The speaker system design limits sound frequencies into 200 Hz ~ 12 KHz and features a soft bass designed for equine listening comfort. The speaker also disbursed the music in 360 degrees resonating from the four open areas of the top of the speaker. The equine music by Janet Marlow was played every day in the “Repeat All” mode. The volume was set in the mid-range; at about 65–70 decibels. The equine hearing comfort levels are between 60–80 decibels in general.

The results of the massage group were significantly lower than the results for the music group. To simplify the graphs, in both Figures, the values of SD are presented as only upper or lower bars, nevertheless, each value of SD above the mean was equal with those below the mean.

The race performance parameters are presented in Table 2. Horses in the massage group achieved better results than those in the control group with regard to the number of races won, prize per race and success coefficient. Music group had significantly higher prize per race than the control group. All the studied performance parameters did not significantly differ between music and massage groups.

**Figure 2** Salivary cortisol level determined after the end of training sessions in studied groups of horses during following months of the training season (means + SD). 1, 2, 3 ...= following months of the study; * = means in Massage Group are significantly different than in Control Group; + - means in Massage Group differ significantly, in comparison to Music Group.

Discussion

The results of the present study clearly show that both stress-coping methods (music meant to be relaxing in the stable and relaxing massage), brought positive effects. Introducing those methods significantly decreased the release of cortisol. The amount of cortisol was estimated on the basis of the salivary cortisol concentration. The use of this kind of stress-level estimation is commonly accepted in current research (Schmidt et al. 2010 a and b, Peeters et al. 2010).

The most interesting results concerned the determination of the cortisol level in saliva samples, taken at rest. The lack of differences in the first measurement taken at rest, showed that, as was expected, the three groups showed similar cortisol levels at the beginning of the study. The similarity of the groups was in accordance with the trainer’s opinion on the normal behaviour of all of the horses. Both of the relaxation methods significantly decreased the cortisol release as compared to the control group, during the whole racing season, excluding the fifth month of the study. It is worth noticing that the massage was performed after the training sessions, so the horses were massaged at noon, and they listened to music in the afternoon. The horses were investigated at rest, in the early morning, hence the influence of the relaxation methods was analysed many hours after the relaxation treatments. Our results indicate the long-lasting effect of the relaxation methods on the salivary cortisol level in the racehorses. The positive effect the massage had on the salivary cortisol level determined just after a treatment, was described earlier (Scott and Swenson 2009). In another study, massage reduced the stress level which had been evaluated on the basis of heart rate and behaviour of the horses also during a treatment (McBride et al. 2004). In the fifth month of the study, the horses which listened to music had a significantly higher salivary cortisol concentration than those horses which received a massage. An analysis of heart rate variability in horses which listened to relaxation music, also showed that the effectiveness of this method decreased after some months of the treatment (Stachurska et al. 2015). Perhaps animals get accustomed to the music as time passes. Moreover, the horses in general get accustomed to the training. A tendency to decrease in resting cortisol values was seen in the control group during the study. Thus, probably, the salivary cortisol concentration dropped in the music group in the sixth measurement in comparison to the fifth measurement, because of a general tendency to adapt to the environment. However, the adaptation effects of long-lasting music treatment in humans and animals have been studied less. In fact, many reports describe beneficial effects of short-time use of relaxing music (Kıyıcı et al. 2013, Bowman et al. 2015, Linnemann et al. 2015, 2016).

The analysis of those salivary cortisol samples taken after the daily training sessions, and taken in the fifth and sixth month of the study, showed the clear positive effect of the massage treatment over the music treatment. Exercise performed by racehorses during training increases the salivary cortisol concentration (K#dzierski et al. 2013, 2014a), however, endurance exercise has a stronger effect (Desmecht et al. 1996). Some studies suggest that salivary cortisol level determined after exercise, can indicate the relative intensity of exercise in racehorses (K#dzierski et al. 2013). Generally, the intensity of exercise increases with the duration of training. Therefore, the values of salivary cortisol obtained after the end of training sessions tended to increase, especially in control and music groups. In the following months of the study, we compared horses which were subjected to similar amounts of intensive exercise. Thus, the differences in the salivary cortisol concentration found between massage group and other groups were the evident effect of the massage treatment. Listening to music only appears to influence mental relaxation in the horses, whereas massage has an effect on both the mental and muscle relaxation (Haussler 2009). It is not surprising that the estimated cortisol release after physical activity showed that massage brought more beneficial effects than the music. From the economic and management point of view, though, providing music is much easier than providing a relaxing massage.

Conclusion

In conclusion, both the relaxation massage and the music treatment significantly decreased the cortisol release in Purebred Arabian horses trained for racing. The massage treatment gave better results than listening to music which was meant to be relaxing. Playing music, though, being easier to provide, may be widely introduced to improve the welfare and performance of racehorses.

Funding Statement

The Polish National Centre for Research and Development (grant number 180061) sponsored this study.

Citation

Kedzierski W., Janczarek I., Stachurska A., Wilk I. (2017) Massage or music meant to be relaxing, result in lowering salivary cortisol concentration in race horses. Pferdeheilkunde 33, 146-151; DOI 10.21836/PEM20170206

Correspondance

Witold Kedzierski PhD, Department of Biochemistry, University of Life Sciences in Lublin, Akademicka 12, 20-033 Lublin, Poland; email

Contributor

Janet Marlow

Founder and Sound Behaviorist, Pet Acoustics

In swine production, one of the stages where there is a higher percentage of mortality is between the birth and the weaning of piglets. The mortality of piglets is associated in part with the stress of the sows, due to the restriction of high motivation behaviours such as to root and due to the establishment of social hierarchy in piglets.

One strategy that has been used in various species to reduce stress is the use of classical music. However, in a previous study carried out by the authors, it was found that the sow's response stimulated stress-type behaviours with classical music instead of relaxation. In this study, the use of frequency-modified music by composer and sound behaviourist, Janet Marlow, was proposed and adjusted to the auditory comfort range of the swine hearing range, as environmental enrichment. Frequency-modified music has been clinically tested in horses with results that positively influenced their performance in races (Stachurska et al., 2015). It is hypothesized that music that is frequency-modified based on hearing range, produces a relaxing effect in piglets that stimulates affirmative social behaviour, improves weight gain and reduces mortality.

Purpose of Modifying Stress Behaviours in Piglets

Piglets show aggression to other piglets within the first week of life while forming a teat order.
Introducing new pigs into a group may lead to aggression as the pigs establish social ranks. Pigs may spend 1–2 minutes nosing each other, vocalising, and then biting until one of the pigs retreats.
During estrous cycles, sows may show severe aggression toward newly added sows.
During breeding, boars may fight and become very vocal.
Using tranquilizers such as azaperone (2.2 mg/kg) or amperozide (1 mg/kg) can help reduce aggression but may not be economical.
Tail biting is seen mostly in confined pigs.
Overcrowding and boredom seem to be the main causes of aggression. Slatted floors without bedding, low-salt diets, and low-iron soil seem to predispose pigs to tail biting.
When the sow is stressed, usually, the sow will bark to warn piglets walking by her head and then later attack them, biting them to death.
Regrouping or overcrowding increases stress levels as well. These two factors (confinement and crowding) lead to chronic stress, delayed puberty, and failure to reproduce. On the other hand, acute and mild stress such as transport and gentle handling accelerate estrous cycles.

Environmental enrichment in early stages is usually successful. Feeding smaller quantities more frequently and providing toys, bedding to root, corn on the cob, and clean tires can be enriching and mentally stimulating for pigs. The inclusion of species-specific swine music is an enhancement to their enrichment to diminish stress.

Swine Hearing Range Data

The hearing of pigs range from 42 Hz to 40.5 kHz with a region of best sensitivity from 250kHz to 16kHz. Because these animals are unable to localise high-frequency tones, it seems unlikely that selective pressure to use the interaural spectral- difference cue for sound localisation is behind their high- frequency hearing. Instead, researchers suggest that these and other hoofed mammals evolved high-frequency hearing in order to use monaural locus cues which prevent front/back locus reversals.

Process for Composing Swine-Specific Music

Using the Logic Pro program, original music based on the swine hearing range sensitivity was originally composed and modified by frequency and decibel levels accordingly. The music was designed to be broadcast at a comfortable volume in an agriculture setting considering a modest amount of noise and squealing coming from multiple pigs. Speakers were provided which were pre-loaded with repeating, modified swine music placed near three large areas of the pigs interacting during less daily activity. The music permeated the environment with specific tones, volume and frequency content to elicit calm behaviour. Proposing that the music will trigger an ear/behaviour response to the piglet's listening comfort as opposed to the transmission of other pig sounds causing reactive stress behaviour.

Included in the compositions are sounds of nature such as water streams and songbird vocalising to add to the environment. The goal here is to help the pigs feel their natural life to ease stress in an unnatural setting.

Instrumentation

Flutes, Harp, Strings, Chorus-Voice, Nature Sounds, and Piano- Synthesizer. Most of the [Pet Acoustics] music has been modified within 10,000Hz to 12,000 Hz, within the comfort zone of swine hearing.

Sound Behaviorist and Founder of Pet Acoustics, Janet Marlow, in her music studio.

Materials and Methods

The study was carried out in a commercial swine farm in the central zone of Chile. A total of 14 litters were used in two rooms, 7 per room was one of the rooms where the music played in (Grupo Música, GM), while in the other room it was kept in normal conditions (Group Control, GC). The music was played between 8:00 and 4:30 p.m., from one day before delivery until weaning, by means of a music system with 2-audio system speakers, Sony model Mhc-rg590s.

For the study, the animals that were closest to the speakers were selected. The speaker’s volume did not exceed 75 dB, a parameter that was evaluated with a sound level meter (model MS-6708). The music used in the study for the selected pigs consisted of ten compositions of designed music, with sustaining instruments and sounds of nature. The frequency levels were placed in the hearing comfort zone between 10,000 Hz and 12,000Hz, with the auditory spectrum of the pigs being between 40.5 Hz and 40 kHz (Heffiner and Heffiner, 1990).

Productive parameters such as mortality, were measured by birth weight / weaning weight and face injuries. The behaviour was recorded and recorded by CCTV cameras. By sampling the litter and discontinuous recording with intervals of 1 minute, measurements were made of the proportion of times that the piglets performed play, rest, and aggression behaviour. Breastfeeding on day 0, 7, 14 and 21 of lactation.

Results and Discussion

Studies on the use and effect of music in pigs are scarce (eg de Jonge et al., 2008), so this is a line of research that has an interesting projection. In the present study, the parameters such as mortality, birth and weight weaning of the piglets did not show significant differences with the music (p> 0.05). Thus, music did not improve productive performance, as occurred in racehorses (Stachurska et al., 2015).

However, this result may be related to the time of exposure to music, because in the study, the aforementioned differences were found in the performance of the careers after three months of exposure to music that was frequency-modified and in the present study the piglets were exposed to music from one day the birth to the weaning, that is no more than 22 days. As for the behaviour, on day 0 a smaller proportion of time spent in the GM attacks than in CG (p = 0.001). When comparing both groups throughout breastfeeding, it was found that the music stimulated more rest (p = 0.004) and reduced the rate of aggression (p <0.001).

Conclusions

This is the first study using music that is specifically designed for swine hearing. The process of species specific music to calm behaviour has been proven in other biometric studies modifying pulse rates, HRV and activity levels in dogs, cats and horses. It is concluded that the swine-specific music had a positive effect on the behaviour of the piglets, so it can be attributed to the calming effect, thus increasing their animal welfare in an agricultural production system.

Authors

Jimenez, MV 1., Plaza, A. 1, Sepulveda, D. 1, Acosta, J. 2 and Atlagich, M. 2 Zapata, B 1 *,1. Universidad Mayor, Campus Huechuraba, Camino La Pirámide 5750, Santiago Chile. 2. Agrosuper, Camino La Estrella 407, Rancagua, Chile.

References

Jonge, FH et al. 2008. Appl. Anim. Behav. Sci.,115 (3), 138-148; Heffner, RS., Heffner, HE. Hearing Domestic Pigs 1990, 48 (3): 231- 40; Stachurska, A. et al. 2015. Journal of Equine Veterinary Science, 35 (5), 650-656; Marlow, J. et al. 2022, Equine Music Study, International Animal Health Journal, Volume 8, Issue 4, (4) 24-27; Marlow, J. et al. 2021, Feline Music Study, International Animal Health Journal Vol. 8 Issue 2, (3) 20-23; Marlow, J. et al. 2021, Canine Music Study, International Animal Health Journal Vol. 9 Issue 2, (6) 36-41

Contributors

Janet Marlow

Founder and Sound Behaviorist, Pet Acoustics

Olga Beatriz Zapata Salfate

Coordinator of Ethology and Animal Welfare, Escula de Medicina Veterinaria en Universidad Mayor

Clinical StudiesJanet MarlowJuly 28, 2023International Animal Health Journal