What should I feed my mice? – RSPCA Knowledgebase (2024)

Mice are interactive and interesting animals full of personality. They like the company of other compatible mice, and many will also readily accept human companionship if socialised to people early in their lives. Mice need an interesting environment, species-appropriate nutrition and care and your time and attention and to thrive.

Mice are omnivores (they eat plant and animal material). They will eat a wide variety of food if offered.

Mouse feeding guide

• Mice should be fed a combination of fresh fruits and vegetables and good quality mouse/rat pellets or cubes. The quantity should be appropriate to the pellets being fed and the age, size and life stage of your mice. Ensure these pellets have a protein content of at least 16% & fat content of 4-5% [1]. Any fruit and vegetables should washed before these are given to your mice [2]. Some examples of suitable fruit and vegetables include: broccoli, broccolini, bok choy, capsicum, corn, zucchini, cucumber, herbs, beans, snow peas, peas, carrots, beetroot and celery and apples (remove seeds first), pears, banana, melons, stone fruits and carrots. Mice can also eat legumes such as beans (e.g., butter or kidney beans), lentils, and chickpeas.
• Fresh food should be removed from the housing within 4-6 hours if not eaten, to avoid spoilage [3].
• Grapes/raisins, chocolate, avocado, garlic, onion, rhubarb, coffee, tea, alcohol, and walnuts must not be fed as they are toxic to mice. Lettuce should be avoided as it can cause diarrhoea in mice [4].
• As mice in the mild would naturally forage, it is a good idea to scatter portions of their daily food around their enclosure to encourage natural foraging behaviour and activity. Mice also naturally eat their faeces (droppings/poo) to help them absorb vital nutrients that they need such as folic acid and vitamin B12 (called coprophagy or cecotrophy) [1–4]; it is important that they be allowed to do this.
• Avoid feeding mice a seed/grain mix, as these are too high in fat and can contribute to obesity and nutrition-related disease [1, 2]. Mice tend to ‘select’ and only eat their favourite bits in the mix and, consequently, miss out on some important nutrients.
• Mice must be provided with access to fresh clean water at all times. Water bottles should be checked daily to ensure that the mechanism is working properly, as mice may push food or bedding into the mechanism through the valve which will block it, or a water bottle may leak, leaving the mice with no access to water [3]. Adult mice need to drink approximately 6–7 mls of water per day [1].
• The following food items should be considered as treats only and should only be offered in very small amounts: unsalted raw nuts, cereals, grains, seeds (e.g., flax seeds), breads, low-fat yoghurt and cheese, cooked wholemeal pasta and brown rice. Obesity is a common problem in mice, so treats should only be fed occasionally and in very small amounts. Treats that are high in fat and sugar should be avoided (e.g. sweets, ice cream, fast food).
• Please ensure that any changes to the diet are made gradually to avoid gastrointestinal upset.