Rats are prone to respiratory illnesses and also tumors. Female rats that have not had a litter, not been spayed, and are about 18 months old are at high risk for developing tumors.Bumblefoot, a bacterial infection caused by Staphylococcus Aureus, called ulcerative pododermatitis. Cages with wire floors are the major cause of bumblefoot. As your rat walks across the wire, it causes cuts and abrasions on little ratty feet, and through those cuts, the bacteria enter. Signs include large lumps that are red and hard on the underside of the paws. If left untreated, the infection can spread to the bones and blood stream. The most common treatment is antibiotics. To prevent this infection, if your cage has wire floors, cover the floors with cardboard, a sheet of newspaper, vinyl, or other similar items.
Itching causes quite a few problems. Your rat's nails may be too long, so when it scratches, it breaks the skin, leaving scabs. In turn, these itch, making the scabs worse. Scratching may be caused my mites, allergies, too much protein, eczema, fungus infection, or stress.
A deadly illness in rats is called mycoplasma pulmonis, caused by bacteria. Symptoms include lots of sneezing, wheezing, labored or noisy breathing, coughing, squinting, red-brown tearing (like blood), and rough fur. Sadly, this disease is not curable, although if it has not advanced enough, it is controllable. If you suspect your rat is infected, immediately take him to the vet to get started on antibiotics. It is highly infectious, so when looking for a new rat in the pet store, check for any of the above symptoms. If you see one rat with symptoms, then don't buy rats from that store.
Overgrown Teeth can be a problem. Rats' teeth grow continuously throughout their lives, so things to chew on are a must. A rat wears down its teeth mostly by eating and bruxing. Overgrown teeth can cause sores that prevent your rat from eating, so weight loss will be a symptom. If your rat's teeth are overgrown, it is best to have them trimmed by your veterinarian. You could probably do it yourself, but someone could get hurt.
Pasteurella multocida is a very uncommon disease among rats, but it is possible for them to acquire it. This disease is fairly dangerous as it can be passed onto humans and other animals. It is passed through bite wounds, through the air, contaminated water bottles, direct contact, and infected mothers who pass it on to their young. There may be no symptoms or sudden illness or death; blood infection (septicemia) is common, pneumonia with head tilt, nasal discharge, ocular discharge, and ulceration of a bite wound.
Pasteurella pneumotropica is a bacterial disease that lies dormant in most rats. When the immune system weakens, the disease starts to take over. Symptoms include sneezing, labored/congested breathing, weight loss, chattering, conjunctivitis, abscess of the harderian gland (gland behind the eye that produces porphyrin), inflammation of the interior eye, mastitis, infertility, spontaneous abortion, skin abscesses, and bulbourethral gland infections (only males), which is larger than normal testicles.
SDA and Sendai virus are similar to HIV. It is deadly to rats. Most often, rats are infected through a new rat. Quarantine your new rat for at least 2 weeks to see if it develops any flu like symptoms. Wash your hands thoroughly after handling your new rat, and change any clothing that has come in contact with it as well.
Sialoacryodenitis is a highly contagious viral disease. It is usually seen among young rats. Symptoms vary depending on the age and immune status of the rat. Signs are seen in 2 to 4 week old rats with no maternal antibody protection. Symptoms include squinting, blinking, rubbing eyes; sneezing and swelling of the neck area; swelling below or around the eyes, bulging eyes, red-brown tears, and self-trauma to the eyes.
Euthanasia is a good option for your rat. It is not painful for your rat, and is not stressful. It is a humane and gentle act.
Try to find a veterinarian in your area that will treat rats. Ask what the exam fee is, if they examine rats, spay/neuter rats, and other procedures. Your vet might see 2 rats at once for the same price as one exam.