Dogs and wolves split from a common ancestor around 40,000 years ago.
Today, they share many of the same traits, such as howling at the moon and running in packs.
Now researchers have found another similarity; dogs benefit from being born, like a wolf, in the spring.
Scientists have found that domesticated pups born in this period of time are less likely to suffer from heart disease than those born at other times of the year.
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They are called man’s best friend for good reason, but the loving heart of a dog is still the same as their wolf ancestors. Although dogs can be born year-round, the animals birthed in April and May are far more likely to have a healthier heart (stock)
The study of 130,000 dogs looked at 253 different breeds and used information from the Orthopedic Foundation of Animals (OFA) which has information on a huge amount of animals.
Information was gathered on an animal’s date of birth, fur colour, sex, breed, registration number, test name, test date, report date (because the report date can differ from the test date) and test conclusion.
This process resulted in a comprehensive dataset of dogs with cardiovascular issues.
The researchers then used an algorithm to decipher all the data from the OFA and came to one of three conclusions for each canine: ‘abnormal’, ‘equivocal’, and ‘normal’.
They found that dogs born in April and May had the lowest risk of heart problems, 20 per cent and 27 per cent lower than the average.
This is in stark contrast to the pups born in July and August that are at the highest risk level – 44 and 33 per cent higher.
Dogs only breed year round as a result of their domestication by humans.
It seems our interference in the lives and breeding patterns of dogs has caused the animals born at ‘unnatural’ times to be less healthy.
This may be due to their early exposure to air pollution.
Dr Mary Regina Boland, from University of Pennsylvania, led the study and said the wolf hypothesis is ‘possible’.
The study looked at 253 different breeds of dog and used information from the Orthopedic Foundation of Animals (OFA). Using an algorithm (pictured), the researchers came to one of three conclusions for each canine’s cardiac health: ‘abnormal’, ‘equivocal’, and ‘normal’
Wild wolves are pack animals and born only in the months of spring. Scientists have found that domesticated pups born in the same time period are less likely to have a heart attack than others (stock)
There is evidence that the time of year an animal is born causes a predisposition to a variety of illnesses and conditions.
This is not limited to dogs, and also includes all species – even humans.
For example, previous research found that people born in the northern hemisphere in January and April are at the highest risk of coronary heart disease.
This is believed to be as a result of exposure to sunlight, pollution or the flu virus after birth.
Dr Boland believes this is the most likely cause of the disparity in heart attack rates amongst dogs.
She said: ‘[It] looks like it could be early gestational exposure to air pollution.’
The research was published in Scientific Reports.