Husbandry - Small Mammals

Introduction

Many diseases in small animal medicine concern poor husbandry, so it is vital to be well informed on the requirements of the small mammals commonly seen in practice.

Rabbits

Housing

Indoors or outdoors is possible.

Outdoor housing should provide shade and shelter from wind and cold

Indoor free range only requires a cage large enough to stretch out when laying on its side. Recommended indoor housing includes plastic bottom and wire top - easily cleaned and well ventilated; glass is not appropriate.

If the rabbit is on a wire mesh floor make sure that the openings are small enough so that the rabbit's foot cannot slip through the wire; also offer solid non-slip surface to provide rest off the mesh and prevent foot problems.

If there is more then one rabbit, each animal should have its own cage. It is good to provide functional spaces: laying down/sleeping, activities, latrine. Hiding places are important.

Ideal substrate is grass hay; a foam rubber pad, towel covered with newspaper and a thick layer of timothy hay is also acceptable. Wood shavings such as pine or cedar should be avoided (oils can cause respiratory/skin issues and has been associated with elevated liver enzymes).

Cages should be cleaned daily to remove feces and urine; gentle soap and hot water or dilute bleach solution are best. Rabbits generally have clean habits: droppings/urine in same place every time, can be trained to use litter box (place in litter box every few minutes when first acquired).

Rabbits should be housed in temps 15-23°c and low to moderate humidity (30-60%). Rabbits tolerate cold better then heat. They shiver when cold, and cannot sweat except through sweat glands in the lips. Rabbits pant ineffectively and when sufficiently dehydrated stop panting. They do not increase water intake with high temperatures, heat actually seems to inhibit drinking. Rabbits can use ears to dissipate heat, they usually actively seek shade and burrow. They are sensitive to temperatures higher than 28°c.

They can be housed in same space with other pets if the other animals adapt to rabbits. Pet birds and well-behaved dogs are ok, but cats are often unpredictable.

It is not good practice to house rabbits with guinea pigs. Rabbits carry Bordetella bronchiseptica asymptomatically and can transmit the infection to guinea pigs.

Diet

Dietary fibre stimulates gut motility, essential for normal digestion. Diets low in fibre can lead to hypomotility, changes in GI pH and microflora, wool block from increased hair consumption and cheek tooth overgrowth.

Pellets can be fed, including -

commercial alfalfa-based pelleted diets which are balanced but low in fibre

high-fibre, timothy-based pellets are available (Bunny Basic/T, Oxbow, Murdock, Forti-Diet, Kaytee)

Grass hay (timothy, prairie, oat, brome), legume hay (alfalfa) should be given ad lib. Alfalfa hay is ok for healthy rabbit; avoid in sedentary obese rabbits, geriatric rabbits or those offered vitamin or mineral supplements. Alfalfa contains higher levels of protein and calcium and can cause urolithiasis or urinary ‘sludge’.

Veggies - collard, mustard, dandelion greens; carrot, beet and broccoli tops; alfalfa sprouts, clover, parsley, lettuce and cabbage

Recommended diet - unlimited hay, some leafy green veggies, a very small amount of high-fiber low-protein pellets.

Allow access to water at all times; water bottle or heavy dish. Raabbits can go for several days without feed (coprophagy), cannot go without water for longer than 24 hours or less in hot weather. They have high water intake (50-150mL/kg body weight).

Guinea-Pigs

Housing

Healthy guinea pigs produce large amounts of faeces, often defecate in food and water containers, turn over unstable containers and are known to place chewed pellets in the opening of their sipper bottles.

Plastic, metal or wire caging with good ventilation is recommended. The cage does not have to be enclosed because pigs do not jump or climb. Flooring shoul be solid or wire mesh, but holes must be small enough to prevent foot entrapment and there must be an area of solid flooring in the cage. The enclosure needs to be large enough to move around with enough space for a hide box.

Bedding - newspaper, shredded paper, straw, aspen shavings. Pine or cedar should not be used, as they cause contact and respiratory irritation.

Quiet area out of direct sunlight must be provided and the recommended temperature range is 18-26°C. They are better able to tolerate cool than warm temperatures and are susceptible to hyperthermia.

The housing should be cleaned thoroughly on a regular basis (2x per week). Heavy food containers that are easy to disinfect and sipper bottle for water are best.

Diet

Food preferences are established early in life and guine pigs often refuse to eat if their food is changed in type or presentation. It is therfore important to expose young to various types of pellets and vegetables when young.

Recommended diet - guinea pellets (free choice or measured) and grass hay (timothy, orchard grass, oat) supplemented with fresh vegetables. Commercial pig pellets contain 18-20% crude protein and 10-16% fibre. Guinea pigs require a dietary source of vitamin C - 10mg/kg daily, which is found in veggies, fruits or supplemented in the water. Pellets are usually fortified with ascorbic acid but half of it is lost by 90 days after the food is mixed and stored at 22°C. Increased temperature and humidity accelerates oxidation, so it is best to assume that the food has none. Leafy greens like kale, parsley, beet greens, chicory, spinach; red and green peppers, broccoli, tomatoes, kiwi fruit, oranges contain a good amount of vitamin C. It can be added to water at 1g/L - open containers lose 50% content in 24hours. The vitamin C deteriorates more rapidly in the presence of metal, hard water or heat and the supplemented water must be changed daily to ensure adequate amounts are ingested.

Ferrets

Housing

Ferrets can be housed singly or in groups. The choice of indoors or outdoors depends on the climate.

Indoors - Multi-level wire cages are useful when it is necessary to confine the animals. Floor can be either solid or wire. NO glass tanks due to poor ventilation. Wooden cages can be used but care must be taken to urine proof corners, lower 3rd of walls and floors.

Outdoors - A portion of the cage should be shaded for protection from extreme heat or cold. The enclosure must be escape proof. Ferrets do not tolerate temps above 32°c especially with high humidity. In climates where temperature drops below -6°C, a heated shelter is necessary.

Slings, hammocks, shelves can be built into cage to add additional sleep/play areas. Dark, enclosed sleeping area can be created using towels, old shirts, cloth hats, commercial sleeping products (tubes/tents) or similar items. If the pet eats cloth, cardboard, plastic or wooden box with access hole can be used instead. At least one sleep area per ferret should be provided.

Ferrets can be litter box trained relatively easily. They back up into corners to defecate or urinate, so box sides should be high. A pelleted litter material is recommended instead of clay or clumping litter. Ferrets have a short GI transit time so litter boxes should be easily accessible.

There should be a safe play area with a variety of objects (boxes, bags, plastic pipes).

“Ferret proofing” the house: Block off all holes to outside or to areas which ferrets cannot be retrieved from, cover bottom of couches/chairs/mattresses with a piece of thin plywood or hardware cloth - ferrets like to burrow in soft foam rubber, which is not only destructive but may also result in a foreign body problem. Restrict access to recliners. No foam or latex rubber items (cat/dog toys, athletic shoes, rubber bands, stereo speakers, headphones, pipe insulation) should be within ferret's reach.

Diet

Ferrets are strict carnivores, designed to eat whole, small prey. In nature, they would only encounter carbohydrates in prey's partially digested stomach contents. They have a short GIT, minimal gut flora, few enzymes, and so cannot use carbohydrates efficiently or digest fibre.

Diet should be high in fat, high in good-quality meat protein, with minimal carbohydrates and fibre. High quality kitten food or commercially prepared ferret food is recommended. Avoid dog or cat food. Supplements to dry food - whole prey (chicks, mice, rats), fresh raw organ or muscle meat, raw eggs, omega-3 oils, fish oils or meat fat can be added to increase fat content. Some ferrets tolerate dairy products.

Ferrets develop olfactory preferences for foods during first three months of their life and preferences set by four months of age (when they leave the nest in the wild). It is difficult to change an adult ferrets diet.

Water must always be available in sipper or heavy crock-type bowl. Ferrets like to play in the water, so the bowl should not be easy to overturn. Supplements should not be added to the ferrets’ water.

Chinchillas

Housing

Chinchillas can be housed individually or in group housing. They are very active, acrobatic animals and require a lot of space. Large, multilevel cages allow for climbing and jumping. Welded wire mesh is preferred as they often chew wooden cages. The housing should include areas for eating, sleeping, exercising and latrine.

They are shy animals so need places to hide such as PVC pipes, plastic or cardboard boxes. Soft bedding to absorb waste and decrease pressure on feet such as recycled paper products, shredded newspaper, aspen shavings is recommended. Cedar and pine should be avoided.

Chinchillas best in cool, dry environment, 10-20°C. They do not tolerate dampness and are prone to heat stroke at temperatures greater than 30°C. In high heat, the housing may be cooled by using electric fans or placing plastic bottles filled with ice in the enclosure.

In their natural environment, they have 12 hour photoperiod. Full spectrum lighting might be helpful to keep them content and healthy. The housing should be cleaned thoroughly at least 2x per week. A diluted bleach solution is the preferred disinfectant.

Dust bath should be provided daily or at least several times per week. Sanitised chinchilla dust is available in pet shops. 9:1 mixture of silver sand and Fuller’s earth can also be used. Beach/playground sand is not suitable. The recommended way to provide a dust bath is by putting 2-3cm depth in a pan big enough for chinchilla to roll around in. Sand bath should be removed from cage when done to prevent faecal contamination and over bathing.

Diet

Chinchillas eat mainly at night. Their specific nutrient requirements are still unknown. Commercial diets are available, some are just a mixture of rabbit, guinea pig and rodent pellets that provide vitamin C, are lower in protein and fat, have same fibre content as rabbit diet, and the pellets are longer to make it easier for the chinchilla to hold. Accepted formula is 16-20% protein, 2-5% fat and 15-35% bulk fibre.

Recommended diet: good quality grass hay supplemented with small amounts of chinchilla or rabbit pellets and fresh vegetables.

Any changes in diet must be made gradually.

Clean, fresh drinking water should be provided in sipper bottles or heavy bowls and available at all times.

Hamsters

Housing

Most hamsters should be kept singly as they will fight if kept in pairs or groups. Easy to clean cage is recommended with lightweight, easy to remove plastic bottom, sides deep enough to contain bedding, wire top and large door. There should be at least one hide box. Dishes for food should be small and heavy and a water bottle checked and refilled daily.

Bedding- recycled paper, compressed wheat straw, citrus litter, aspen or oak bedding, corncob are all acceptable, avoid pine and cedar wood. The cage should be cleaned twice a week.

The cage must be kept in a cool area of the house during the summer because hamsters get stressed by hot and humid environments. Twelve hour light cycles are recommended.

Diet

Seeds can be given as treats, not as a sole diet. Formulated pellets or blocks are available. The diet should consist of minimum protein content of 16% and fat content 4-5%.

Gerbils

Housing

Gerbils are territorial and best kept singly. Cannibalism can result from keeping incompatible pairs together.

Easy to clean cage is recommended with lightweight easy to remove plastic bottom and sides deep enough to contain bedding, wire tops and large door. A minimum of one hide box is recommended.

Provide a dust bath and small, heavy dishes for food. Water bottles must be checked and refilled daily. Thwelve hour light cycles are the best.

Bedding can consist of recycled paper, compressed wheat straw, citrus litter, aspen or oak bedding, corncob. Avoid pine and cedar wood. The cage should be cleaned 2x per week.

Diet

Formulated pellets or blocks are available. Seeds should only be given as treats, not as a sole diet. The recommended minimum protein content is 16% and fat content 4-5%.

Rats

Housing

Rats can and should be group housed. They like to climb ramps and ropes and use various hide boxes. The cage should be easy to clean with lightweight easy to remove plastic bottom with sides deep enough to contain bedding, wire tops and large door.

Small, heavy dishes for food and water bottles (check/refill DAILY) should be provided. Food can also be hidden in suitable objects to give them something to do.

Bedding can consist of recycled paper, compressed wheat straw, citrus litter, aspen or oak bedding, corncob. Pine and cedar shaving should be avoided as they can predispose rats to respiratory disease. They contain the volatile oil thujone. Thujone is a respiratory irritant and may be tumorogenic. Thujone can cause convulsions and cortical brain lesions if there is prolonged exposure.

The enclosure should be cleaned 2x per week. Twelve hour light cycles are recommended.

Diet

Seeds should only be given as treats, not as a sole diet. Formulated pellets or blocks are available. Minimum protein content of 16% and fat content 4-5% are recommended.

Rats are harder to convert to a new diet.

Husbandry - Small Mammals Learning Resources
Flashcards Test your knowledge using flashcard type questions	Small Mammals Q&A 08

References

Quesenberry, K. (2004) Ferrets, Rabbits, and Rodents Clinical Medicine and Surgery St. Louis: Saunders

Mitchell, M. (2009) Manual of Exotic Pet Practice St. Louis: Saunders