Switching a Ball Python From Mice to Rats: When and How

Thinking about switching a ball python from mice to rats? Do it by weight. At about 450 grams, a Small rat (45 to 85 g) is close to 10% of its body weight. That's the rule many keepers use. Offer one Small rat on your normal feeding day. If your snake refuses it, feed a mouse and try again next time.

Not sure of your snake's size? Text Mike its weight at (520) 451-4380 and he'll help you pick.

Below: why keepers switch, how to time the first rat, and what to do if your snake says no.

Why do keepers move ball pythons to rats?

Ball pythons outgrow mice. That's the main reason.

An Adult mouse tops out around 30 grams. A vet-reviewed growth chart from The Vet Desk lists 1,000 to 3,000 grams for ball pythons 5 years and older. At the 10% rule, a 1,500 g snake needs a meal of about 150 g. That's five or more Adult mice, or one Medium rat.

Care guides say the same thing. A vet-written care sheet at PetMD says a growing ball python "can be transitioned to a diet of larger mice and rats." The Vet Desk puts it simply: "As your snake gets larger, small rats are ideal."

Here's what one rat does for you:

• Fewer feeders per meal. One Small rat weighs about as much as two or three Adult mice.
• Less time at feeding. One strike instead of three.
• Fewer animals to watch. If you feed live, one rat is easier to supervise than several mice.
• Room to grow. Rats come in sizes from Small to Jumbo, so the food keeps up with the snake.

When should I switch my ball python to rats?

Go by weight, not age. Ball pythons grow at different speeds, so two snakes of the same age can be hundreds of grams apart.

ReptiFiles suggests feeders that weigh 10% to 15% of your ball python's body weight. It also suggests weighing your snake once a week on a digital kitchen scale. Mike's size chart uses the 10% end of that range.

Here's how snake weight lines up with Mike's sizes:

The in-between zone. From about 300 to 450 grams, one Adult mouse is too small. Most Small rats are a bit big. Keepers handle this a few ways. Some feed two smaller mice in one meal. Some offer a rat from the low end of the Small range. ReptiFiles notes that two smaller prey items in one meal are fine. Keep the total near 10% of the snake's weight.

What about age? The Vet Desk chart lists 270 to 360 g at 6 months and 500 to 900 g at 1 year. So many ball pythons reach rat size somewhere in their first year. But your scale is the real answer.

What size rat should I offer first?

Start small. Pick a rat at or a little under 10% of your snake's weight. For a 500 g ball python, that's a Small rat around 45 to 50 g.

A rat that looks a lot like the mice it's used to is easier to accept. One keeper on ball-pythons.net suggests a young rat about the same size as the mouse your snake already eats.

Then keep everything else the same:

1. Same day and time. Ball pythons are night feeders. A vet column in REPTILES magazine says they do best when food is offered at night, in the dark.
2. Same method. If you feed frozen-thawed, thaw the rat the way you thaw mice. If you feed live, offer it the way you always do.
3. Same spot. Don't move the snake to a new box only for this meal.

Feed frozen-thawed? Good. The switch works the same way with frozen rats. Lots of keepers feed frozen, and ReptiFiles calls frozen prey "generally considered optimal."

If you feed live, be careful. Stay and watch the whole time. ReptiFiles says to take the rat out if it isn't eaten within 15 to 30 minutes. VCA Animal Hospitals says never to leave live prey in the cage for more than two hours. Rodents can bite. Never walk away from a live rat in the enclosure. Our step-by-step live feeding checklist covers the rest.

After a meal, leave your snake alone. PetPlace says not to handle a snake for 48 hours after it eats. Handling too soon is a common cause of snake regurgitation.

Ready to try rats? Call or text Mike at (520) 451-4380. Tell him your snake's weight, and he'll help you pick a Small rat. See all Small rat sizes and prices.

What if my ball python refuses rats?

It happens. To a ball python, a rat can smell like a brand new food. A refusal isn't an emergency. Here's what keepers on ball-pythons.net and in other switching threads report trying, in order:

• [ ] Feed a mouse and try again next time. Keep your snake eating while you work on the switch.
• [ ] Scent the rat. Rub it with used mouse bedding or with a thawed mouse.
• [ ] Mouse first, rat second. Offer a small mouse. Once it's eaten, offer a small rat right after.
• [ ] Hold off a feeding or two. One keeper suggests waiting a feeding or two until the snake takes the rat. Only try this with an adult at a good weight, never with a small or young snake.

Keep weighing during the switch. ReptiFiles says a skipped meal is fine if your snake isn't losing more than 10% of its body weight. If it drops past that, or shows other signs of illness, see a reptile vet.

Some ball pythons never switch. Keepers call them lifelong mousers. If yours is one, it's fine to feed two or three mice per meal. It takes more mice, that's all.

Timing matters too. A vet column in REPTILES magazine notes that some ball pythons stop eating in the winter months. Starting a switch during a seasonal fast can look like a refusal when it isn't. Read why ball pythons stop eating in winter, and see why a ball python won't eat for other causes.

Mice vs rats for ball pythons: a quick comparison

Here's how the two stack up for a 600 g ball python. At the 10% rule, it needs a meal of about 60 grams.

Prices are per animal, plus Arizona sales tax (6.1%). Sold as feeders, not pets. Buy 10 or more and each one is 10% off. It's 20% off at 25 and 30% off at 50 or more.

For more on picking the exact rat, see our pillar guide, what size rat for a ball python. For the full chart of growth by age, see the ball python weight chart. Mike's feeder size guide lists every size in grams, plus the names other sellers use.

Ready to try rats?

Weigh your snake. If it's 450 grams or more, it's ready to try a Small rat. If it's close, the in-between zone tips above will carry you there.

Mike breeds live feeder rats in the Tucson area, from Small to Jumbo. No shipping. No freezer to fill. Call or text Mike at (520) 451-4380 with your snake's weight, and he replies the same day.

Nothing ready in your size? Get batch alerts and Mike will email you when a new batch is ready. Want to know who you're buying from? Meet Mike.