Pet Rats Care Guide

Pet Potential/Behavior:

• Easy to care for.
• Very little odor.
• Affectionate and intelligent animals that bond quickly to their owners; rarely bite.
• Albino rats tend to be the most calm and easily handled.
• Hooded rats may be more aggressive and active.
• Basically nocturnal, but can be active during the day.
• Need at least 30 minutes each day for exercise.
• Dogs, cats, and ferrets are rats’ predators.
• Often difficult to litter train (fecal).

Anatomy:

• Rats are characterized by elongated bodies, short fur, small eyes and ears and hairless tails.
• Anatomically, rats have open inguinal canals, a diffuse pancreas, a divided stomach, a large cecum and an ospenis. Rats do not have gallbladders.
• Rats do not vomit due to the presence of a limiting ridge at the junction of the esophagus and stomach.
• Because rats have poor eyesight, they rely on whiskers and scents for sensory input and spatial orientation.
• Mammary gland tissue may extend from over the shoulders to the perianal region.

Sexing and Reproduction:

• Male rats have a scrotum, making them easily differentiated from female rats.
• The anogenital distance is roughly twice as long in males as in females.
• Only female rat possess nipples.
• Rats are communal and male and females maybe combined in an uncrowded enclosure for breeding.
• If a female is not bred by 8months of age, her pelvis will fuse and she may have difficulty giving birth later.
• Anecdotally, spaying may help to prevent mammary tumors, which are common in middle aged to older rats.
  

Housing:

• Housing should be constructed of escape proof wire mesh with plastic or metal solid flooring and should be large enough to allow nesting, burrowing and exercise.
• Minimal enclosure size guidelines for one adult rat are 24” x 24” x 12” (61 x61x30cm).
• A secure wire screen clamped top or other roof is necessary to prevent escape.
• Ideal room temperature should be 65 80 F (18 26 C).
• Ideal humidity should be 40 70%
• Because rats are social and need companionship, they should be maintained in same sex or altered sex groups.
• Suitable substrates include shredded paper (non inked), recycled newspaper composite materials or pellets, hardwood chips or shavings and compressed wheat straw.
• Cedar should not be used as litter because it has been show to affect microsomal oxidative liver enzymes.
• Bedding should be a minimum of ¼ to 1 inch deep and changed at least 1 2 times per week.
• Exercise may be provided in the form of a large exercise wheel and climbing toys.
• Housing should be cleaned weekly to minimize respiratory disease risk.

Diet:

Rats are omnivorous rodents.

Rat/rodent pellets provide a complete diet. Recommended brands include Mazuri, ZuPreem and Oxbow Pet Products.

Small amounts of fresh fruits, vegetables may be added.

Seed based diets are not recommended as they do not meet nutritional requirements and predispose to obesity.

Adults require 5 10 g of pellets per 100 g body weight daily and 10 ml water per 100 g body weight daily.

Fresh water should be available at all times, ideally provided via a drinking bottle or sipper tube.

Food consumption should be monitored when new food is offered because rats may be suspicious of new food.



Restraint:

• Most rats will allow you to pick them up by placing the hand firmly over the back and rib cage.
• A rat can also be scooped up with both hands.
• The head can be restrained with the thumb and forefinger behind the jaws.
• Scruffing the loose skin at the nape of the neck can help restrain an active rat, but many rats object to this.
• Rats may bite aggressively if restrained against their will.

Blood Collection:

• For blood collection, remove no more than 10% of total blood volume (1.3 ml per adult rat).
• Tuberculin syringes with 25 27 ga needles can be used to collect small amounts of blood from lateral saphenous or lateral tail veins (superficial on either side of tail).
• Alternatively, the ventral tail artery (ventromedial aspect of tail) can be accessed under general anesthesia.

Physical Examination:

• Annual veterinary visits should include a physical exam and a review of diet and husbandry. The need for fecal analysis and blood hematology and chemistry should be discussed.
• Bi annual or quarterly examinations to assess weight, dental health, nail trimmings and overall health are recommended.

Most common Disorders:

• Weight loss/obesity/malnutrition
• Overcrowding/stress/suffocation
• Sudden death/Trauma
• Murine respiratory mycoplasmosis M pulmonis
• Cilia –associated respiratory bacillus
• Corynebacterium Kutscheri
• Sendai virus (most common in laboratory rats)
• Sialodacryoadentis virus (SDV) Cervical salivary gland inflammation
• Chronic progressive nephrosis
• Overheating/Chilling/Heat stress
• Malocclusion/overgrown incisors
• Ectoparasitism
• Congestive heart failure
• Pituitary Tumor
• Ulcerative pododermatitis
• Hymenolepis spp.
• Mammary tumors (fibroadenoma most common)
• Salmonellosis
• Septicemia
• Ptyalism
• Hemobartibekkisus (in colonies)

Zoonotic Potential:

• Rat bite fever Streptobacillus moniliformis
• Salmonellosis
• Ectoparasitism
• Leptospirosis
• Hantaviral disease
• Lymphocytic choriomeningitis virus (LCMV)