Fancy Rat Health Guide

Pet rats are prone to several health problems like being overweight, getting hurt (usually from a fall or being bitten), having teeth that don't fit together (malocclusion), parasites, and respiratory tract infections. Rat illness can be caused by mycoplasmas, and a wide range of other bacteria and viruses. Respiratory infections can become long-lasting or come back, and usually need to be treated with antibiotics.

Rats secrete porphyrin so if you see red secretions from a rat's nose or eyes it probably isn't blood. Over production of these natural secretions can be caused by illness or stress. Typically rats will secrete a small amount and groom it off, however if you notice it all the time they probably need to see a vet. 

Here is a link to a Rat Health "Cheat Sheet" for some quick tips and information: https://ratguide.com/reference/ratmedhelp.pdf

Scabs, mites and parasites

If you notice excessive scratching, see small scabs or small black spots in and around your rats ears they probably have mites. This can be treated with Ivermectin readily available in Revolution. It is handy to keep a tube of this on hand so you can put a few drops on the skin on the back of the rats neck. You should treat all rats, do a thorough cage clean and hot wash all toys and bedding. Dosing guide is:

(Add dosing for Revolution)

Malocclusion 

Malocclusion is the misalignment of the front incisors, it can develop due to injuries to the mouth area or be present from birth due to genetics. The most obvious sign is visible overgrowth or uneven growth of incisors.

A rat with malocclusion may salivate, rub at its mouth with its feet, or exude a foul odor from the mouth. Other signs include inability to chew hard food, weight loss, or sores developing in or near the mouth. Broken upper or lower incisor(s) is a sign that malocclusion may be an issue.

In healthy rats the incisors are properly aligned and able to be maintained at a certain length through the process of natural teeth grinding without requiring something hard to chew on.

In a rat with malocclusion, the teeth are not aligned properly, and natural grinding cannot take place. The incisor(s) continue to grow and curve, and if not kept trimmed results in trauma to the soft palate, infection, and abscesses, which in turn will eventually lead to the rat starving. Malocclusion may be due to injury (such as loss of a tooth due to root damage or trauma), dental disease, genetics, tumors, or other noninfectious reasons.

It is important to check and do a visual exam of your rat’s teeth and mouth on a regular basis to access his oral health. Teeth that are misaligned should be trimmed on an average of every 2 weeks to 2 months (depending on the rate of growth). Infected molars can cause oral abscesses that can go undetected until they actually make their way to the rat’s epidermis. Abscesses are a concern if a foul odor is present in the rat’s mouth. In such cases the veterinarian may elect to open and debride the abscess and remove the infected tooth.

In cases of oral abscesses, or infections due to malocclusion, it is wise to institute a soft diet during the healing process.

Source: Rat Guide (Malocclusion) 

Lumps and Tumors

Abscess

Abscess are common in rats and look similar to tumors and cysts. Abscesses can pop up almost over night and they grow faster than tumors or cysts, as it is usually inside the skin, when you move the skin the lump will also move. They are usually caused by a scratch or other wound which the skin grows over, the wound will typically heal before the abscess appears. Males often get them in the genital area, usually they will open and drain on their own.

When found on other body parts it usually can be allowed to sort itself out and it can take several weeks so if your rat isn't bothered by it you can 'wait and see'. When natural healing has taken place there will be a dark area on top of the lump, which in time will open and drain, a small portion of skin/scab will fall off and you might notice a small hole, as rats are very hygienic they will be able to keep it clean themselves.

You can speed up the draining process by applying a warm compress to the area to soften the skin/scab and encourage the puss to the surface, then using a tiny needle (blood lancets are good) prick two small holes on either side of the abscess, puss should start to escape, you might need a gentle squeeze to assist. If BLOOD not PUSS comes out when you prick this usually indicates a tumor or cyst and you should consult a VET.

You might need to repeat the warm compress and squeeze a couple of times, keep an eye for any sign of infection and monitor.

Cysts

Cysts are small sacs filled with either liquid or semi-solid waxy/oily substances. They are created by the oil glands in the skin, they often look like a small abscess. They grow slowly and usually stay on the smaller side, they will usually create a small hole in the top and it might look darker than the rest of the sac.
Usually these resolve on their own but if it continues to grow it should be emptied, they will come back until the internal sac is destroyed so you might need to squeeze several times. Vet assistance might be required if it keeps growing back or if it becomes very large. 

Tumors

Tumors and respiratory infections are the two most common conditions Fancy Rats get. Tumors are more common in females and can be benign or malignant.  It is important to give weekly health checks so you notice tumors early and can seek assistance from your vet. There are many different types of tumors that rats can develop, the few most common types of tumors are discussed below. 

Mammary Tumors 

Mammary are the most common tumor found on female rats but males can also get them. Female rats stop ovulating around 18 months which results in changes to estrogen, up to half of female rats will get mammary tumors, they usually present in the armpit, chest, belly or groin area. Usually they are soft and flat in the beginning and get harder as they grow. Mammary tumors can become necrotic and fill with puss, they can also contain small milk pockets. 

Benign tumors are usually loosely attached, it can move separately from the surrounding skin and muscle. If the tumor feels firmly attached it is possibly malignant, this 'feel test' is not a diagnosis you will need a vet to check and confirm. Surgery isn't usually too successful as tumors tend to come back quickly but they could be managed with a medication called prednisone.

Pituitary Tumors

These are more difficult to diagnose as pituitary tumors grow inside the skull, it begins to press on the brain and over time causes neurological issues. Symptoms can come on suddenly or over time, they can also hemorrhage which will trigger severe symptoms very suddenly. 

Poor coordination and partial loss of arms and legs usually appear first. Their arms might be held stiff and hands curl into a fist, you will probably notice porphyrin build up and they could have strange behavior. They might walk in circles or into object, they could act confused. They might not be able to bend their arms so they cannot feed themselves and require hand feeding. 

Once diagnosed by a vet you might have the option to treat with cabergoline (DOSTINEX®) and will need to monitor their quality of life and in time make the decision to euthanize. 

Lumps on Throat

If you see a lump on your rats throat it could be a tumor, abscess, swollen lymph node or inflamed salivary gland. The lymph node can enlarge from a bacterial infection or cancer, salivary glands can enlarge from viral or bacterial infections.

Glands and lymph nodes can appear very quickly like abscesses do. Tumors tend to grow more slowly. If you notice a sudden lump on your rats throat try treating with an anti-inflammatory, if it starts to shrink within 24 hours it is probably not a tumor, abscess or cyst. You will then need to visit a vet to find the cause of the infection and treat accordingly. 

Hormonal Aggression 

Hormonal aggression (or HA) is a fairly common issue with rats, particularly in NZ. It typically affects males, although females can also get it as well. HA typically shows up between 6-8 months, but it can show up as early as 3-4 months and sometimes even well up to 18 months. 

Note: This is why it is SO important to wait for males to be 18 months before they're bred, because hormonal rats will make more hormonal rats. 

Signs/Symptoms: 

There are many symptoms of HA and it’s not always the same for each rats. Some are mild, while some are not. For some it comes on suddenly without warning and others its can be a gradual thing.

Typically the symptoms include: 

• puffy fur around other rats

• hissing/spitting at other rats

• Side-barging/Butt-barging (to make themselves look bigger) 

• Defensive when you touch them, particularly the lower back area

• Excessive scent marking 

• Excessively trying to dominate cage mates (hump, power groom, scent mark) 

• Biting/lunging towards rats and/or people 

• constantly chasing cage mates 

• cage aggression towards rats and people 

• Boxing/Upright dominance 

• fighting 

What to do?

The one and only cure for HA is for the rat to be desexed. With HA, it is fairly time critical - so the earlier its picked up & dealt with, the easier it will be for the rat to recover. 

Firstly you'll want to remove the hormonal rat from the cage and set it up in a spare cage. This is important for the safety of your other rats as hormonal rats are unpredictable and the fighting can escalate without warning. Secondly you need to book a neuter with a rat-savvy vet. A neuter done by a rat savvy vet is a fairly routine surgery and the risks (while present) are low if the vet is experienced with the procedure. The recovery time is fairly short and they should recover within a few days. However sometimes it can take much longer for their behavior to improve.

Re-introductions:

This seems to be another variable thing. Some rats will go back with their cage mates immediately and some can take months.  It is important to do intros as if the rats have never met before - so neutral space intros like a bathtub so you can quickly intervene if things get out of hand. Sometimes hormonal males will never intro back with males, and often prefer living with females only. So it is worth keeping this in the back of your mind if your rat does not re-intro back with other male cage mates. 

Respiratory Issues

Lower Respiratory Infections 

The lower respiratory system in rats is comprised of the trachea, bronchi, and lungs. The lungs of the rat, like in humans, lie on each side of the heart in the chest cavity, but rat lungs differ from humans in the division of the lobes. The left lung in the rat contains one lobe while the right contains four lobes. In humans the right lung contains three lobes while the left contains two. 

While there may be some structural differences and variation of nerve innervation of the lungs between humans and rats, for the most part, respiration remains the same.

In newborn rats the lungs are not yet mature. The alveoli and alveolar ducts do not develop until the 7th day following birth. Up to that point the gas exchange of breathing occurs by way of smooth-walled channels and saccules. By day 13 the restructuring of lung parenchyma is complete.

Respiratory disease is among the most common health issue in rats. Learning to recognize your rat’s normal healthy behavior can alert you to early signs of illness. In addition, seeking treatment at the earliest signs of illness (e.g., upper respiratory issues or porphyrin staining) can often increase life span and comfort for your rat.

Source: RatGuide (Lower Respiratory)

Upper Respiratory Infections

The upper respiratory system of rats is much the same as other mammals. It includes the nares (nostrils) which open into the nasopharynx, the sinuses, the Eustachian tubes which open on the dorsolateral wall of the nasopharynx, the epiglottis which is located in the oropharynx and covers the opening to the larynx, and the beginning of the trachea where it goes on to form the two main branches of the bronchi which enters the lungs.

It is easy to see by the connection between these various structures how the introduction of irritants can harm, or how infections or neoplasms can spread to adjacent structures within the respiratory system.

Upper respiratory disease is a common health issue in rats that can result in acute or chronic, infectious or non-infectious, subclinical or overt signs of illness and may be attributed to a variety of environmental factors, as well as infection by bacterial, viral, or fungal agents. It is important to become familiar with your rat’s normal behavior and appearance in order to spot signs of illness and treat earlier. Seeking veterinary care early in the illness can help to prevent an illness from becoming more severe.

Source: RatGuide (Upper Respiratory)

Wounds: Is it Infected or Not?

Rats are very good healers and will heal from most small injuries fairly quickly, such as surface lacerations. However sometimes complications arise and their wound might become infected. Here are some things to look out for to see if your rat needs a vet visit for further treatment and medication.

• Pus is a clear indication a wound is infected. Pus or cloudy fluid draining from a wound is both good and bad - it means the wound is infected, but that the body is currently fighting off infection

• A yellow crust has formed around the wound

• The scab has increased in size/thickness

• The area around the wound is red

• The wound area is very tender and is painful for you to touch or interact with and your rat might prevent you from looking at it

• If there is an increase in swelling or the wound has become swollen after 24 hours

• The wound shows no sign of healing or improvement after 3-4 days 

If your rat is experiencing any of these symptoms, then we advise you seek out vet help immediately. 

Recommended Vets

• common things to look out for that vets get wrong eg doxy in water