Small herbivores can't make their own vitamin C the way most other mammals can, which is why guinea pigs in particular need it topped up through diet rather than left to their own biochemistry — and a treat built around that gap is solving a real nutritional job rather than just adding variety to the bowl.

This is a wheat flour and Timothy grass hay-based treat, with ground dried locust beans, ground dried peas, brown linseeds and soya oil making up the bulk, and dried cranberries and dried blackcurrants each at 0.5%. Vitamin C is added at 12,500mg/kg, alongside concentrated paprika and carrot for colour.

• For rabbits, guinea pigs and chinchillas
• Vitamin C added at 12,500mg/kg
• Dried cranberries and dried blackcurrants, each 0.5%
• Crude protein (min) 8.0%, crude fat (min) 2.0%, crude fibre (max) 12.0%, moisture (max) 10.0%
• Not a grain-free recipe — wheat flour and oats both appear in the ingredients
• 100G pack

On the dose. Supreme's own guidance is 1 to 2 treats a day, as a supplement to a regular diet rather than a replacement for it — fresh water should always be available, and if you're already feeding a vitamin C-fortified pellet, it's worth checking you're not doubling up.

Who it's for: owners of guinea pigs especially, since they're the species most reliant on dietary vitamin C, alongside rabbits and chinchillas kept on the same feeding routine.