Rabbit Diet Guide: What to Feed, What Not to Feed, and Why Most Advice Is Wrong

Hay is medicine, not just food

A rabbit's digestive system relies on continuous fiber throughput. The cecum (a large fermentation chamber in the hindgut) processes hay fiber into cecotropes -- soft, cluster-like fecal pellets that the rabbit re-ingests directly from the anus. These cecotropes provide essential B vitamins, proteins, and probiotics that are critical to rabbit health. Rabbits that do not eat enough hay develop GI stasis -- a potentially fatal condition where gut motility slows or stops, allowing gas to build up and cecal bacteria to proliferate pathologically. High-fiber hay intake (minimum 1-inch hay depth available at all times) is the single most important preventive against GI stasis. Rabbits should eat hay constantly throughout the day.

GI stasis is the most common life-threatening emergency in pet rabbits

Gastrointestinal stasis occurs when the normal 12-18 hour transit time of food through the rabbit gut slows or stops. Signs: reduced or absent fecal output (fewer or smaller droppings than normal, or no droppings for 12+ hours), reduced appetite, abdominal distension, and hunched posture indicating pain. GI stasis is not self-resolving -- it is a medical emergency. A rabbit that has not produced fecal pellets for more than 12 hours or has stopped eating should be seen by a rabbit-savvy vet within 4-6 hours. Treatment includes fluid therapy (to hydrate gut contents), gut motility drugs (metoclopramide or cisapride), pain management, and syringe-feeding if the rabbit will not eat voluntarily. Untreated GI stasis can be fatal within 24-48 hours.

Most fruits and certain vegetables cause digestive upset when overfed

Fruits contain high sugar content that disrupts the delicate cecal microbiome when fed in excess. Signs of carbohydrate overload: soft, paste-like cecotropes sticking to the anus (cecotrope dysbiosis), loose stools, and diarrhea. Truly dangerous foods for rabbits include: iceberg lettuce (contains lactucarium, which can cause diarrhea and lethargy), avocado (toxic -- can be fatal), rhubarb (high oxalates, potentially fatal), onion, garlic, and leeks (destroy red blood cells), and seeds or pits from fruits. Foods to offer sparingly: fruits (max 1-2 tablespoons per 5 lbs body weight per day), starchy vegetables (carrots and corn are high-sugar), and high-calcium greens (kale, spinach, chard) which can contribute to bladder sludge if fed daily in large amounts.

Pellet quality matters more than quantity

The rabbit pellet market is dominated by muesli mixes (multi-ingredient pellets with seeds, dried vegetables, and colored extruded pieces) that were shown in UK feeding studies to cause selective feeding -- rabbits ate the high-sugar, high-fat components and left the high-fiber pieces, leading to obesity, dental disease, and GI problems. Plain, extruded timothy hay-based pellets (not alfalfa-based for adults) with 18-22% crude fiber, 14-16% crude protein, and less than 1% fat are appropriate for adult rabbits. Alfalfa-based pellets are appropriate only for rabbits under 7 months (who need higher calcium) and for underweight or senior rabbits requiring weight gain. Limit adult pellets to 1/4 cup per 5 lbs body weight per day maximum.