Probiotics are one of the most common supplements pet parents ask us about, and one of the most confusing to buy. Labels quote big numbers in different units, and some promise to fix everything. This guide explains what a probiotic can do for a dog or cat, what it can't, and how to compare one product with another.
What a probiotic is
A probiotic is a supplement of live, friendly microbes, usually bacteria and sometimes a yeast. Your pet's gut already holds billions of them. They help break down food and keep harmful bugs in check, and they play a part in the immune system. A probiotic adds more of the helpful kinds. A prebiotic is different. It's a fibre the friendly microbes feed on, and many good products include both.
When a probiotic can help
- Changing food. Switching brands, or moving between packaged and home-cooked food, often upsets stools for a few days.
- Stress and travel. Boarding, moving house, festivals with fireworks and long car journeys can all unsettle the gut.
- After antibiotics. Antibiotics kill helpful bacteria along with the harmful ones. Ask your vet about timing.
- Everyday upkeep. For pets that tend to have soft or smelly stools.
Home-cooked food is a good diet for many pets. Cooking makes it safe, but the heat also means no live cultures reach the bowl, so home-cooked meals aren't a source of probiotics.
When to see a vet instead
A probiotic is everyday support, not treatment. Go to a vet if you see blood in the stool, repeated vomiting, diarrhoea lasting more than a day or two, weight loss, a pet that won't eat, or constant scratching and paw licking. Itching in particular has many causes, including allergies, parasites and skin infections, and the gut is only one of them.
What to look for in the best probiotics for dogs: five label checks
1. The culture count, and its unit
Counts are given in CFU (colony-forming units). The number on its own means little until you know whether it's per gram, per serving or per pack. "10 billion per gram" and "10 billion per pack" are a hundred times apart in a 100 g jar. Work out what your pet actually gets in one day's serving.
2. Which microbes
Look for the names of the groups or strains, such as Lactobacillus, Bifidobacterium, Bacillus or Saccharomyces. Bacillus and the yeast Saccharomyces cope well with stomach acid, which helps more of them reach the intestine.
3. A prebiotic
Fibres such as FOS (fructo-oligosaccharides) or inulin feed the friendly bacteria and help them settle in.
4. Dose by weight, for your species
A good label tells you how much to give a 5 kg cat and how much to give a 30 kg dog. If it gives one dose for every animal, ask why.
5. Allergens and storage
Check for ingredients your pet reacts to, such as soy or chicken. Live cultures don't like heat or damp, so look for clear storage instructions and a "use within" period after opening.
How long until you see a difference?
Stools often settle within one or two weeks. Changes to skin and coat take a month or more. If you see no change after a month, talk to your vet. The cause may be something a probiotic can't reach.
A note on our own product
We make Cani-Gut, a pre- and probiotic powder for dogs and cats, so we have an interest here. We've tried to write this guide so it's useful whichever product you choose. If you do look at ours, everything above is on its label: the count per gram, the four culture groups, the prebiotic, the dose by weight and the allergens.
