Dr Liesel van der Merwe is a small animal medicine specialist. Send her your questions: This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Dr Liesel van der Merwe

Cats are seasonal breeders and they are induced to come into heat with lengthening daylight hours. Very young cats can fall pregnant, but a young cat will get her first heat at an older age if she matures in winter versus a kitten which matures in spring.

A queen which has just had kittens can fall pregnant within six weeks of birth so they may already be pregnant with the next litter before the kittens are even weaned.

Different to dogs, cats do not show obvious physical changes with heat. There is no bleeding or obvious swelling of the vulva. The main signs are that they start acting strangely: Being overfriendly, tripling with the hind legs and yowling. The expression “cat on a hot tin roof” comes to mind.

A cat will come on heat every two weeks until she is mated, whereas a dog will only come on heat about every six months whether she’s been mated or not or whether she’s had puppies or not. Spay your cats at five to six months old. If you get caught with an unwanted litter, spay the mother at weaning (six weeks).

Unwanted kittens are often dropped off at kitten shelters. Although I have great admiration for the work these shelters do, this stressful environment is not ideal for kittens. Cats are relatively solitary animals and become stressed in high population density environments. Stress causes a decrease in the immune system. Cats in crowded environments generally suffer from chronic viral diarrhoea.

This virus will sometimes mutate and cause feline infectious peritonitis (FIP), a fatal disease where the virus moves from the intestine into the body and blood vessels and causes inflammation and fluid to build up in the chest and abdomen.

This mutation is more likely to cause disease in young stressed animals with an immature immune system. Young kittens exposed to this environment may develop FIP months to a year after being adopted. This is heartbreaking for the new owners.

I always advise people to adopt kittens from low-density populations: When people advertise kittens from accidental pregnancies. If you pick up an abandoned litter and raise them at home, these cats are also less likely to carry the FIP and leukaemia virus. Cats brought up in home environments are in the long run the healthiest and least likely to develop FIP or feline leukaemia.

This is hard to accept as we all want to reach out and help these poor abandoned kittens in shelters. If you want to adopt from a cattery or shelter, ask if the kittens have been mixed with the adult population. This is a no-no.

Shelters should advise people to keep the kittens at home until homes can be found or to keep new additions separate from the resident population as long as possible. At our practice we often home kittens: The criteria is that they have been dropped off at the shelter and have been kept separate from the other cats before being brought to the practice.

Although FIP is not contagious, viral diarrhoea is. Once the kitten has diarrhoea, there is a chance of developing FIP. The percentage cats developing FIP is very small compared to the number of cats that have diarrhoea but, if your cat is unlucky, the results are fatal.

Make sure the kitten you adopt is healthy before taking it to your other animals at home. Snuffles are often also present in these stressed kittens, and this is contagious.

Cats are not really designed to live in close association with other cats. Lions are the only family oriented wild felid. Most of the time there are no real repercussions from overlapping territories, but if stressed, cats can exhibit several abnormal behaviours and illnesses.

Feline interstitial cystitis is a bladder inflammation triggered by stress and environmental management is needed to control flare-ups. Some cats over-groom themselves and may lick themselves bald in patches. If cats are confined to a small space, ensure that they have vertical interest as they like being high up. Get them multi-level scratch posts and a view and allow sufficient litter trays and feeding areas.