Many common Uromastyx health problems can be prevented with proper husbandry. Proper housing includes a dry enclosure, safe substrate, adequate temperature and basking areas, and plenty of space. Humidity can cause respiratory problems and scale rot. Improper substrate such as walnut shells or calci-sand can cause impaction in the gut if swallowed. Improper diet can also result in impaction, as well as vitamin/mineral deficiencies such as Metabolic Bone Disease (MBD).
Always be ready to take your Uromastyx to the vet if the reptile is visibly ailing. Reptiles in general are good at masking health problems because in the wild, the weak get taken out by predators or become ostracized from the group. It is a good idea to have a fecal scan run on new additions to the collection or at a sign of illness. See our Reptile Resources page for links to reptile vets.
Always quarantine your new addition(s) for 30-90 days before introducing them to other animals. Always be prepared to keep animals in solitary enclosures in case of fighting.
Most diet-related health problems in Uromastyx lizards can be prevented by offering a highly varied diet of leafy greens, vegetables, flowers, beans, seeds and a limited amount of fruit.
Metabolic Bone Disease or MBD is the most common affliction of captive reptiles, and Uromastyx are no exception. MBD is a spectrum of disorders related to calcium deficiency, most cases are diet related. The bioavailability of calcium is determined not just by overall calcium in the diet but also the interaction of other vitamins & minerals such as vitamin D3 and phosphorus. When the right balance is not available in the diet, calcium is pulled from the bones.
Signs of MBD include soft jaws, disfigured bones, swollen joints, trembling and general signs of ill health. Calcium is for more than just bones. Internal problems include lack of muscle control, loss of liver, kidney and nerve function and problems in blood clotting. Severe cases of MBD do result in death, usually from heart failure. The healthy level of calcium in the bloodstream is roughly 1%. Over-supplementation with calcium is rare but possible.
Providing a balanced diet is crucial to prevent Metabolic Bone Disease in Uromastyx lizards. Choosing foods that are both high in calcium AND low in phosphorus are the best way to give uros the building blocks these reptiles need to function properly.
The final component in calcium absorption is Vitamin D3, either via diet supplementation or UVB exposure.
Provide your Uromastyx with either a humid hide or allow him to burrow to regulate his humidity needs. Uros will retreat to their burrows at night after digesting their food; in the wild, they have extensive and deep burrows and move around accordingly. Burrows up to 3 feet have been discovered, with humidity levels ranging from 50-90% depending on the season and rainfall. Temperatures are fairly constant at 70-75 degrees.
Under most circumstances, Uromastyx don’t need water bowls and should instead be provided with plant foods with high water content. Additionally, providing a light mist on the sides of the enclosure in the morning once a week to allow them to drink should be fine as long as the humidity levels don’t exceed 40% for an extended period of time.
Emaciated uros that have gone off-feed are also dehydrated. When they don’t eat, their stomachs shrink, their energy level drops and appetite is suppressed. Therefore, it is important to offer drinking water for these individuals. Dehydration also affects their ability to process proteins, so remove any beans/legumes from the diet. No insects!
It is important to address the issue of dehydration before resorting to force feeding. The impact of this can affect health later on. Get appropriate vet care in issues of severe dehydration and starvation before attempting force feeding.
Excess protein is hazardous to dehydrated Uromastyx lizards because it over-taxes the kidneys and liver. Over time, too much protein for any Uromastyx can affect kidney and liver function. For tortoises, a safe level of protein has been estimated at an average 4%. Strive to keep the amount of protein from plant foods low by avoiding excessive feeding of beans and other legumes. Green legumes such as alfalfa, clover, etc. are good to feed in moderation.
Do not feed insects to your Uromastyx. Insects are not part of their native diet for most species. They are unnecessary at best and dangerous at worst.
Herbivorous reptiles such as Uromastyx species are uniquely adapted to the local environment. They do not have the same digestive systems as mammals, with their masticating teeth, multi-chambered stomachs and cud-chewing, that are useful when eating tough vegetation. Uromastyx rely entirely on their gut flora (and possibly small stones) to break down plant matter and extract nutrients. This is a generally inefficient process and keeping the right balance of microorganisms is very important. This gut flora includes “beneficial bacteria” and even protozoans and nematodes. This is combined with the uro’s preferred 130 degree basking temperature to digest their meals.
The use of antibiotics, such as Baytril, and parasite treatments, such as Panacur, will kill off these microorganisms, making it difficult for the Uromastyx to digest food. NutriBAC df is a respected brand of probiotic. Repashy “Veggie Dust” also contains beneficial ingredients to boost gut flora.
Most of the time, Uromastyx are fine if they skip meals for up to a week. Common causes are food preferences, changes of season, stress, low temps, and sadly, illness.
In the wild, Uromastyx change foods with the season, and different species tend to eat slightly different foods. Ornate Uros eat a lot of acacia flowers and tend to go nuts for any small yellow flower (such as from dandelions or budding wild arugula). Don’t drastically change the diet from one day to the next, but rotate foods in and out gradually.
Normal Changes in Appearance
As your young Uromastyx grows and matures, you will see general changes in appearance. Males and females (depending on species) will gain color and some will exude a waxy secretion from their femoral pores on their inner thighs.
Reptiles shed as they grow and their skin is renewed. Unlike people, whose skin cells slough off one at a time, most reptiles like snakes, geckos and other lizards, tend to go into shed all at once; snakes have an easier time pulling it all off at once because they are unhindered by appendages. However, with our friend the Uromastyx, the lizard may be in a state of constant shed throughout the warm seasons! Often they look like half-peeled bananas. It’s best to not pull off their skin unless it’s restricting their circulation around their wrists and toes.
Uromastyx will often eat their delicious skins, regaining some of the nutrients that went into creating it in the first place. Eating the shed also minimizes the chance of a predator coming across it and alerting them to the presence of a nearby meal.
The salt glands of Uromastyx, as well as other herbivorous and marine reptiles, is an adaptation of the lateral nasal gland. This comes in handy by removing salts these animals encounter through diet or other environmental exposure. Since most reptiles do not produce liquid urine, evolution has adapted the lateral nasal gland to eliminate these substances as “snalt”. 
The term “snalt” refers to the salt-snot, the ring of white deposits around the lizard’s nostrils. It is composed of excess salts in the diet. Lentils, papaya, carrots, corn, and sweet potatoes are comparatively high in sodium and potassium which form these salts. They shouldn’t be avoided as they are highly nutritious foods, just keep them on rotation. This “white stuff” on your uro’s nose can simply be wiped away and will fall off on its own.
Stress & Handling
Whenever you suspect your Uromastyx is not well or not adjusting to its home, you should stop handling. Even relatively friendly reptiles such as Uros are stressed by too much handling. How much is too much? You don’t want to handle daily if you see signs of stress, hiding during the day in warm weather, and not feeding.
Mature male Uromastyx are often brightly colored and easily distinguished from females in this way. However, for immature animals or to make sure you don’t have a “male mimic”, you can sex uros by gently lifting the tail and looking for a “v” or “u” shaped crease starting at the base of the tail extending back. The bulges on either side are the hemipenes of the male. The tail body of a female will appear more uniform as it does not house the male reproductive organs!
Other secondary sexual characteristics include coloring mentioned above, wider, larger heads and “jowls” in males. Both males and females can have femoral pores, males tend to have larger ones.
Never probe a Uromastyx! This can cause harm to the internal tissues and can be very stressful to the reptile. Probing is for use on snakes but is still not recommended for novices. Uros should not be “popped” either.
Disorders & Diseases
Keeping a Uromastyx in an enclosure that is too moist, or failing to dry them off after a soak can lead to tail rot. Bacteria or fungi can build up in the tail crevices and lead to infection or “rot”. The tail turns dark and can fall off. A trip to the vet is always advisable, as problems with tail tips could also be dry gangrene from an injury and not tail rot.
Undigested food or foreign objects (rocks, hair, wood chips, bark, vermiculite from potting soil, etc) can form a mass in the digestive system and cause an impaction. Signs of impaction include inability to defecate, or straining to go, and passing narrow, skinny poops. If you’ve noticed a lack of poo in your enclosure, and your Uromastyx is lethargic, this could be signs of infection or other illness.
Soaking in warm water can help pass the blockage, but if normal bowel movement does not return quickly, so don’t put off a vet visit! Impactions can cause death if not dealt with quickly.
Maintaining good husbandry and making sure foods are high in moisture and free from dirt and debris will cut down on the chances of your Uromastyx becoming impacted. Improper substrates, especially crushed walnut shell and cacli-sand also cause impactions.
Faulty UVB bulbs can cause eye irritation and often blindness.
http://www.uvguide.co.uk/phototherapyphosphor-info.htm is a great resource if you suspect your Uromastyx or other reptile has photo-kerato conjunctivitis.
Uromastyx are generally hardy, but improper husbandry or exposure to infected reptiles can introduce viral, bacterial, or fungal infections. ALWAYS follow proper quarantine when obtaining new animals. If your uro appears ill and you don’t know why, please take your pet to a qualified reptile vet!
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