London breeders have a knack for getting the most out of the animals they breed, but it can be hard to make sure the offspring have good health, according to new research. 

Researchers at the University of Sussex examined the health and behaviour of 4,000 pairs of London puppies and found that while the animals looked healthy, they could be more susceptible to illness, such as pneumonia and heart disease. 

“The puppies had more health problems than the parents, with some having more than 20 infections and other conditions, compared to just a few in the parents,” lead researcher Prof John Taylor, from the University’s Institute of Veterinary Medicine, told New Scientist. 

“[We] found that the offspring of London breed cats were less likely to have respiratory disease than the litter of litter mates.”

 The researchers found that in the offspring, there were more infections and heart defects than in the littermates.

The scientists also found that London breed puppies were more susceptible than their littermates to illness.

“Our results suggest that the health problems of London breeding cats are partly caused by poor nutrition,” Dr Taylor said.

 “We think the problems are caused by a combination of poor health and poor socialisation.”

The researchers are currently looking at how to improve the health of the London breed, so if you have an older, sickly cat, you could also benefit from an early-warning collar, as the researchers suggest.

It’s important to keep an eye on your cat’s health because it can also affect the health or behaviour of the offspring.

The study is published in the journal BMC Public Health.

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