by Heather Bjornebo, DVM, DABVP(Reptile-Amphibian Practice), CertAqV
Many clients with rabbits are unaware of the important health benefits of spaying rabbits. Spaying refers to the surgical sterilization of a veterinary patient by removing their ovaries and, at least in the United States, their uterus. There are many benefits to having your rabbit spayed that go beyond preventing unwanted litters.
The biggest benefit is the elimination of the potential to get uterine cancer. Uterine tumors are extremely common in rabbits as they age. Some studies have shown as many as 44% of rabbits developing some form of uterine abnormality in their lifetime. Another important benefit of spaying your rabbit is spayed rabbits are also significantly less likely to get mammary tumors (breast cancer).
Beyond the medical benefits of spaying your rabbit, there are also benefits that will help her make a better pet for your family. Spayed rabbits are better at using their litterbox and tend to be less aggressive. Spay rabbits are easier going and oftentimes more affectionate.
So what should you consider when looking for a veterinarian to have your rabbit spayed? Rabbits in general are considered a higher anesthetic risk than dogs and cats so it is very important to find a veterinary hospital where not only is the veterinarian very familiar with your rabbit’s medical needs, but their staff is trained well so your rabbit receives the best care and monitoring during the procedure. While cheaper prices can be found at spay/neuter only practices, often time this lower cost comes with less one-on-one care, decreased monitoring during and after the procedure, and less supportive care such as skimping on IV fluids. Given the special needs of rabbit patients, we recommend rabbits be spayed at a full service exotics practice. To find an exotic veterinarian in your area visit aemv.org and use their find-a-vet search tool.
Did you know that respiratory infections are come of the most common medical conditions seen in pet rats. Both acute respiratory illness and chronic have been well documented. Acute bacterial pneumonia is characterized by sudden onset of symptoms and is often caused by Corynebacterium kutscheri or Streptococcus pneumonia. Corynebacterium kutscheri is often referred to as pseudotuberculosis (a.k.a. false tuberculosis) and is more often seen in older rats. On the other hand, Streptococcus pneumonia is more commonly diagnosed in younger rats and is actually contagious to people. Chronic disease, commonly referred to as murine respiratory mycoplasmosis, is caused by Mycoplasma pulmonis. Co-infections with cilia-associated respiratory bacillus, Sendai virus, or Sialodacryoadenitis virus are common.
Symptoms of respiratory illness in rats include difficulty breathing, rapid respirations, blue gums, sneezing, ocular/nasal discharge, red pigment staining around the nose, eyes, and front paws, lethargy, head tilt to rolling, muffled heart sounds on veterinary examination, and acute death in severe cases.
Following a thorough physical examination, your veterinarian may recommend chest x-rays. X-rays of the skull may also be recommended to evaluate the inner ear. Blood testing may also be recommended to evaluate the body’s response to infection through a while blood cell count and metabolic state through a serum biochemistry panel. Your veterinarian may also recommend microbial culture and a DNA probe (a.k.a. PCR) test for Mycoplasma especially if the patient isn’t responding as expected to treatment.
Initial therapy involves stabilizing the patient. Hospitalization for oxygen therapy is necessary for patients struggling to breathe. Patients should remain hospitalized until stable on oral medications. Your vet will prescribe appropriate antibiotics and anti-inflammatory medications based on the patient’s illness and needs. Additional treatment with bronchodilators, fluid therapy, and assist feeding. Patients with chronic illness may require long term or pulse therapy as well as may be prescribed medications to treat secondary chronic pulmonary hypertension.
Learn more about respiratory disease in rats by visiting our Educational Guide here.
UV light or Ultraviolet light is high energy light than violet but lower energy than X-rays on the electromagnetic spectrum. Ten percent of the light energy produced by the sun is UV light. UV light is invisible to most humans. Small birds, on the other hand, have a forth color receptor in their retinas that gives them “true” UV vision.
UV light is further broken up into UV-A, UV-B, and UV-C.
UV-A is low wave UV. It easily penetrates the ozone layer. This is the light we find in black lights and is known as “soft” UV. Reptiles utilize this light to help regulate behaviors (a.k.a. their circadian rhythm) such as feeding, daytime movement, mating, and similar activities.
UV-B is medium-wave UV or “intermediate” UV and most of this light frequency is absorbed by our ozone layer. Biologically, it is utilized by non-fish vertebrates like reptiles, amphibians, birds, mammals, and even humans for vitamin D synthesis.
UV-C is short-wave UV or “hard” UV. It is ionizing radiation and used in germicidal UV sterilizers. Luckily, the UV-C produced by our sun is completely absorbed by the ozone layer and our atmosphere.
Why do reptiles need UVB light?
Reptiles, like many vertebrates, utilize UV-B light in the synthesis of vitamin D. When UV-B light interacts with the skin it interacts with 7-dihydrocholesterol activating it into cholecalciferol, or vitamin D3. From there it undergoes further transformation within the liver and kidneys to become 1,25-dihydroxyvitamin D3 used for maintenance of calcium balanced within the body. So without UV-B light that first step in producing this vital chemical regulator within the body never happens. 1,25-dihydroxyvitamin D3 is important as it increases absorption of calcium from the diet, decreases loss of calcium in the urine from the kidneys, prevents overproduction of parathyroid hormone, and modulates the activity if the cells of the skeletal system.
Do all reptiles need UVB light?
Diurnal reptiles, such as iguanas, bearded dragons, turtles, tortoises, water dragons, day geckos, etc. all require UV-B for production of active vitamin D3. Crepuscular reptiles, those active at dawn and dusk, have been found to also be able to utilize UV-B to activate vitamin D3. However, they can also utilize dietary vitamin D3 and have been raised in captivity for generations without UVB lighting. Studies in nocturnal reptiles (i.e. pythons, boas) have shown they cannot utilize UV-B for vitamin D3 activation. However, there may be additional benefits that UV-B lighting provides that have yet to be discovered.
What sources of UVB lighting are available to pet owners?
UV-B light for your reptile can be naturally provided from the sun or artificially by using specially designed light bulbs that produce UV-B. Natural sun can only be used by reptiles housed outside. This is because UV-B cannot penetrate glass so placing your pet near a window will not work. UV-B is only able to penetrate the glass of UV-B bulbs because the glass has been specially treated to allow UV-B to penetrate the glass. This coating wears off over 6-12 months of use causing these bulbs to stop producing UV-B light long before they burn out. This is why manufacturers recommend replacing these bulbs regularly. Artificial UV-B is available in 4 different types of reptile bulbs: fluorescent, mercury vapor, metal halide, and LED.
The first is fluorescent which produces light using a low-pressure mercury-vapor gas-exchange lamp that fluoresces to produce visible light. These bulbs produce minimal heat and come in 3 types. The first are the T8 bulbs, this is a second generation fluorescent straight tube bulb (first generation being T12 bulbs and are no longer produced as UV-B bulbs). The second are the compact fluorescent bulbs where the fluorescent tube is formed into a coil or loop and then set into a normal light bulb socket. Both T8 and compact fluorescent bulbs produce similar amounts UV-B. The third and newest type are the T5 or third generation straight tube fluorescent bulbs. These emit stronger light and have more UV-B production than both T8 and compact fluorescent bulbs.
Most UV-B fluorescent bulbs are sold in various strengths, which vary in their labeling depending on the manufacturer. For example, Zoo Med sells them as 2.0, 5.0, and 10.0 bulbs corresponding to 2%, 5% and 10% UV-B production respectively. While Arcadia sells 2%, 7%, 10%, 12% and 14% bulbs. Exo-Terra takes a completely different aproach utilizing a more complex system to help keepers choose the correct bulb based on species and basking distance with bulbs labeled as 100, 150, or 200.
The second type of UV-B bulb available to reptile owners are Mercury Vapor bulbs. A mercury-vapor lamp is a gas-discharge lamp that uses an electric arc through vaporized mercury to produce light. They procude both head and UV-B light. These bulbs are ballasted, when they turn off they need to cool down before they will turn back on, so they cannot be regulated with a thermostat like standard heat lamps. They have a higher UV penetration and UV index than fluorescent bulbs making them ideal for larger enclosures (40 gallons or larger).
Metal Halide bulbs are the third type available on the market. A metal-halide lamp is an electrical lamp that produces light by an electric arc through a gaseous mixture of vaporized mercury and metal halides. This bubl also produces both heat and light, but less heat at a lower wattage than mercury vapor bulbs. These high intensity UV-B bulbs also work well for larger habitats. It should be noted that special fixures are required for these and standard heat domes will not work.
The final type available are LED or light-emitting diode lamps. These are a semiconductor light source that emits light when current flows through it. Relatively new to the market, more research is needed to really gauge how they compare to other bulbs on the market. While expensive, these bulbs are energy efficient and produce little to no heat.
What is UV penetration and why is understanding this important to choosing the right lighting for your pet?
UV penetration is the concept that the farther you get from the UV-B source, the lower the UV-B index is. Different bulbs are going to give you different depths of penetration into the cage. It is important to take this into account when choosing the lighting for your pet. In general, mercury vapor and metal halide bulbs have the highest (or deepest) penetration while fluorescents the penetration is lower. Below are some examples of UV penetration diagrams for a variety of different UV-B bulbs.
What is UV index?
The last area that needs to be touched on is UV index. UV index is an international standard measurement of the strength of sunburn-producing ultraviolet radiation at a particular place and time. It’s an open-ended linear scale, directly proportional to the intensity of UV radiation that causes sunburn on human skin. It was invented to help people effectively protect themselves from UV radiation, which has health benefits in moderation but in excess causes negative effects. We borrow this in reptiles just as a measure of the amount of UVB reaching our pets.
Summary
UV-B lighting is essential for the health of many pet reptiles. Most reptiles require UVB lighting to properly absorb and utilize dietary calcium. Without UVB many reptiles will develop Nutritional Secondary Hyperparathyroidism a.k.a. “Metabolic Bone Disease.” It is important to understand that artificial UVB lights need to be changed every 6-12 months as they will stop giving off UVB light. Both species and cage setup should be considered when choosing the right UVB source.
Cerenia, generically known as Maropitant, is a neurokinin-1 receptor antagonist. It mediates effects of central and peripheral substance P, an excitatory neurotransmitter and is in a class of peptides known as neurokinins. Substance P binds neurokinin-1 receptors which are G protein coupled receptors. As an antagonist, maropitant and others like it, blocks the action of substance P.
Where are neurokin-1 receptors located?
They are located in the central nervous system, heart and blood vessels, genitourinary system, immune system , and gastrointestinal tract.
What are the effects of Cerenia in the body?
These neurokin-1 receptors are involved in blood cell production, wound healing, neurogenic inflammation, cell survival, cell proliferation, pain transmission, endocrine and paracrine secretions, dilation of blood vessels. They are involved with neuronal transmission associated with depression, stress. Cerenia antagonizes the affects in these areas as well as acts on two areas in the central nervous system to stop vomiting: area postrema and nucleus tractus solitaries.
So if rabbits and rodents cannot vomit, why is it often used in exotic companion mammals?
While the anti-vomiting effects in rabbits and rodents not seem as important since they cannot vomit, it does not necessarily mean they cannot feel nausea. Efficacy of maropitant for preventing vomiting is also associated with pmotion sickness in dogs where it blocks final common pathway in the vomiting center of the brain. Studies showed it was very effective in preventing vomiting in dogs premedicated with hydromorphone, an opioid drug often associated with nausea and vomiting in patients. There are reports on Veterinary Information Network as well about its use with rabbits during head tilt and it is thought to maybe be helpful to reduce nausea from vestibular disease. It is also used in ferrets and birds as an anti-regurgitation drug.
What about its use in pain control?
As a neurokinin-1 receptor antagonist, Maropitant has shown to reduce anesthetic requirements of dogs undergoing surgery and can be used to reduce visceral pain. In rabbits, Maropitant reduced the viscerosensory response caused by colorectal distention and it is often in rabbits and guinea pigs as pain control for gastrointestinal stasis.
It also has anti-itch effects!
Since neurokinin-1 receptors are involved in mediating some itch pathways. Substance P is found in nerve fibers in the skin and it plays a significant role in the nerve pathways that are involved in inchiness. antagonizing, or blocking these pathways, can be helpful to reduce itch. Studies have shown similar drugs reducing itch in humans and Maropitant signficantly reduced the itchiness of ulcerative dermtitis lesions in mice.
It can also reduce the creation of abdominal adhesions forming after surgery!
Antagonizing neurokinin 1 receptors decreases postoperative adhesion formation and increases peritoneal fibrinolytic activity. Research in a rat model with the use of a neurokinin-1 receptor antagonist (NK-1RA) was found to decrease postoperative peritoneal adhesion formation by up to 53% at higher doses studied compared to saline controls. This research indicated that the antagonist used blocked the binding of substance P to neurokinin receptors. Left unblocked, substance P is proinflammatory and results proliferation of scar tissue and stimulates excessive blood vessel formation. Furthermore, antagonism appears to increase expression of tissue-type plasminogen activator an important enzyme in the production of plasmin, a protein that breaks down fibrin and scar tissue production. Research in rabbits has shown that intestinal adhesions can be reduced compared to controls when tissue-type plasminogen activator is given intraperitoneally.
But wait… there’s more… how about in respiratory disease
Maropitant has been used to treat canine chronic bronchitis. Substance P acts on the neurokinin-1 receptor in airway inflammation and the cough reflex. Antagonizing substance P showed a significant decrease in cough frequency and severity but no change in inflammation.
So are their side effects for Maropitant we should consider?
Some recommend not giving for more than 5 days in a row since the enzyme responsible for its metabolism, CYP2D15, becomes saturated. It should also be used with caution with highly protein bound drugs as these drugs compete with Maropitant for protein binding and there can be increases in unbound Maropitant in the blood. Also it should be used with caution with calcium channel antagonists as maropitant has an affinity for Ca and K channels. Excessive use may also decrease intestinal motility and it induced intestinal motility disorder in mice.
