Dear Doctor October 2014

Preservatives in cat food; the best time to wean kittens; help for litter box avoidance


Preservatives in cat food

QThere used to be a lot of talk about the dangers of BHA, BHT and ethoxyquin used as preservatives in certain pet foods. Have they been replaced by different ingredients, or are there simply fewer concerns about them now?

Elizabeth M. Randall

ADear Elizabeth: There is currently less discussion about these synthetic preservatives mainly because they have largely been replaced in most dry commercial pet foods. Interestingly, they were removed because of consumer demand for naturally preserved products — not because there was actual evidence that they are harmful.

Most pet foods are now preserved with mixed tocopherols (vitamin E derivatives), citric acid and/or rosemary extract. Curiously, there is less data on safety and efficacy of these natural products than there are for the synthetic preservatives, yet they appeal to consumers because they are “natural.”

There is some evidence that natural preservatives may not be as effective as synthetic preservatives, so this change does place more responsibility on pet food manufacturers to insure that their products are adequately preserved to provide appropriate nutrition throughout the shelf life of the product. Additionally, pet owners are encouraged to check the expiration date on food bags before purchasing.

If pet owners want to avoid preservatives entirely, they should feed their pets a diet of canned food, which utilizes the canning process to keep food from going bad.

Dr. Cailin Heinze, MS, VMD, DACVN

Veterinary Clinical Nutritionist

Cummings School of

Veterinary Medicine

at Tufts University

When to wean kittens

QDear Doctor: I am a recent subscriber to Catnip and I enjoy it very much. I have been breeding Singapura kittens on a very small, informal scale for several years and will soon be ramping up the scale with three fertile females and the launch of a small online cattery.

The lady from whom I purchased my first Singapura weans her kittens (takes them away from mother) at four weeks and five days of age. I am not entirely sure why she is doing this, but she said it had something to do with preventing disease and/or infection from the mother. To me, the kittens seem too small and vulnerable at this age.

My question is: Is this a bit too early, and if so, when would be a more optimal time to wean these kittens?

Michael R. Lehmann

ADear Michael: I am unaware that early weaning offers any health benefit to kittens — and it actually may be harmful. Weaning (the transition from mother’s milk to solid food) can be a stressful event in the kitten’s life, and if improperly performed, may contribute to kitten illness and mortality (coupled with possible behavioral issues, too).

Weaning begins at three to four weeks of age when kittens are offered cat food moistened with water or kitten milk replacer. Kittens first learn to eat by accident, as they step into food and ingest it during grooming. At three to four weeks of age, kittens begin to eat solid foods, although 95 percent of their caloric intake is provided by the queen’s milk.

A progressive intake of solid food continues until the kittens are completely independent of the queen. Most cats are weaned by six to nine weeks of age. Later weaning allows more time for kitten growth and immune system development, which may reduce kitten mortality.

Abrupt removal from the mother cat can have a negative effect on the kittens’ health and socialization skills — they learn to eat, use a litter box and play, among other things — by observing their mother. Ideally, kittens should remain with their mother during weaning and the process handled entirely by the queen. She will inherently know what to do.

Best of luck with the Singapuras!

Michael Stone, DVM

Clinical Assistant Professor

Cummings School

of Veterinary Medicine

at Tufts University

Litter box avoidance

QMy indoor neutered male three-year-old cat was diagnosed with cystitis earlier this year after I found him urinating outside his litter box. Stormy was placed on Clavamox for 10 days, and the crystals and blood in urine disappeared. He was fine until recently — when he started to urinate again outside the litter box.

There are no other cats in the house. I live alone and have changed nothing in the household routine. My veterinarian is also at a loss for his behavior. Because there were a few crystals showing in his urine recently, she deemed it unnecessary to prescribe antibiotics again. I did ask her to issue the Clavamox again for 10 days. She also prescribed seven doses of prednisolone (five milligrams). Her technician suggested replacing the towel under the litter box with a puppy pad, which might work better because it is softer.

I have used the same brand of litter — Feline Pine — since adopting him when he was eight months old. Whenever he defecates, I scoop it out as soon as possible. I also replace the litter and plastic liner once a week. I first place plastic down on the cement floor, then a towel and then the litter box. To clean the soiled areas, I have used Urine Gone and Woolite Stain Remover.

He is alert, likes to play and is up to date on all his vaccinations. Please help.

Cindy D. Foley

ADear Cindy: What you are reporting is a litter box problem, as opposed to one involving marking or medical issues. It is thought that cats with cystitis sometimes associate pain or discomfort with litter box use and that erroneous connection can lead to litter box avoidance and house soiling. That said, your litter box facilities are far from ideal for any cat, so the cystitis he had may have simply been the straw that broke the camel’s back.

Here’s what you should do and why it will help the situation:

Switch to a fine sand-texture scoopable litter. Cats prefer sand-textured litter because they have desert ancestors and using sand is “in their blood.”

Eliminate the plastic liner. Most cats dislike them.

Scoop the litter box once daily. Do not hover and scoop the box immediately after each elimination incident.

Use Zero Odor™ to clean up after future “accidents.” It is available online and at Bed, Bath and Beyond stores. I regard it as the best at eliminating pet odor.

Get rid of the towel and plastic under the box. The towel might be a preferable substrate to the Feline Pine you have been using. Also, having plastic underlay beneath the litter box is a turn-off to some cats.

Do not put down a “puppy pad.” Those contain pheromones and may encourage his urination outside the box.

Make sure you add a second litter box. There should be one litter box per cat plus one.

Make sure both litter boxes are on different levels of the house and convenient for your cat to access.

If you do all of the above, I feel confident that the problem will disappear rapidly.

Nicholas Dodman, BVMS

Animal Behavior Clinic Director

Cummings School

of Veterinary Medicine

at Tufts University


Please enter your comment!
Please enter your name here