One of the biggest risks factors faced by the affected foals is susceptibility to secondary infection. Within three to eight days after birth, the foal may die from infection or is euthanized for welfare reasons.

With rest, the tail returns to normal within a few days. Pain relief, such as a nonsteroidal anti-inflammatory drug may be administered. The symptoms may reoccur.

Biopsies of the skin may be performed to identify the cleavage that takes place at the dermal-epidermal junction. Another test that can aid in a diagnosis of JEB is the positive Nikolsky’s sign. By applying pressure to the skin, transverse movements can indicate slipping between the dermal and epidermal layers. An easier and more definitive test is through polymerase chain reaction (PCR). This method allows mane and tail samples to be genetically tested for the mutated genes that cause the condition. Hair samples must be pulled, not cut, with roots attached. The test can detect both JEB1 and JEB2. Testing costs around $35.00 US per sample.

It has been said by many dog owners that limber tail had been caused shortly (24 hours) after swimming in water that is too cold or on rare occasions too warm and indeed this has certainly produced this very condition. The actual cause is unknown but it may be caused by the narrowing of the space through which the spinal cord passes, typically due to degenerative change to the intervertebral disk spaces. These underlying changes may not lead to visible change until the problem is suddenly exacerbated, such as during physical activity, after trauma, etc. Occasionally other changes are seen prior to or in conjunction with limber tail disease, such as urinary or fecal incontinence, postural abnormalities in the pelvic limb, or pain in response to touching the lower back.

Veterinary treatment or an improved and more stimulating environment may help birds suffering from feather-plucking. Organic bitter sprays are sold in pet stores to discourage plucking, especially of newly grown feathers, although this may make general beak-based grooming difficult for the animal. This is not recommended since it does not address the real reason why the bird is picking feathers.

Recovery is most likely if it is spotted within the first 24–48 hours, and you should seek veterinary advice—a vet may choose to give the animal drugs.

The sick animal should be kept in a cage by itself so that others do not catch the disease—wet tail can be very contagious so sanitize all objects the animal has come in contact with (wheel, food dish, huts, etc.).

If the animal doesn't want to eat, then dry, unflavored oats can be hand fed, which can also help with the diarrhea. The animal should only be fed dry foods, any foods with a high water content should be avoided.

If the animal has an unclean or matted rear-end, this should not be remedied using a bath in water—instead a q-tip (cotton bud) or cotton ball can be used to very gently clean the animal's rear end to avoid discomfort or rashes.

If the animal is not drinking, hydration can be aided by scruffing (i.e. very gently holding the rodent by the extra skin on the back of the neck) the animal so that they open their mouth; then in small, short intervals, water can be provided with a 1 ml syringe. It is very important that this is done slowly, to avoid getting water down the animal's wind pipe. Unflavored pedialyte can be purchased from a grocery store and can be very helpful with wet tail. If feeding is also an issue, a suggested aide is to feed extremely small amounts of no garlic, no onion, no added sugar mashed baby food, and administered using the same scruffing method, and again at a very slow pace.

Treatment includes anti-anxiety medication, anti-depressants such as SSRIs, or sedatives.

Feather duster budgerigars ("Melopsittacus undulatus"), sometimes called budgerigar mops, are budgerigars that have a condition characterised by overly long feathers that do not stop growing at usual periods, giving the bird the appearance of a feather duster. This condition is sometimes known as chrysanthemum feathering. The contour, tail and flight feathers do not stop growing, and they do not have the necessary barbs and barbules for the feather's structure to interlock. The shaft (calamus) is also curved, and so the feathers appear deformed and fluffed out. Individuals with this condition often appear less alert than nest mates. In addition, they are small and some have other defects such as microphthalmia. They lack vigour, often cannot fly and die within a year of hatching. There is no treatment for the condition; birds are often euthanized in the nest.

The condition may be a genetic disorder, caused by a herpesvirus, or perhaps caused by both.

Syringomas can often be diagnosed clinically based on presentation, distribution patterns over the body, lack of associated symptoms and family history. A definitive diagnosis requires a skin biopsy to allow the tissue to be examined under a microscope. Histologically, syringomas have a characteristic comma ("tadpole") shaped tail of dilated, cystic eccrine ducts.

In orange-winged amazon parrots, a heritability estimate of 1.14 ± 0.27 was found for feather-plucking, indicating that a genetic basis exists. This study, however, only involved analysis of full siblings and a small number of birds, explaining the heritability value of greater than 1. Quantitative trait loci (QTL) analysis could provide more insight in possible genetic markers that are involved in feather-plucking.

Ringtail, also known as tail necrosis, is an epidermal disease that may occur in rats, mice, hamsters and other rodents.

In affected individuals, the tail swells as a consequence of annular constrictions along its length (hence the name "ringtail") and subsequent dehydration; in the most severe cases, the process may end up in the tail becoming gangrenous and dropping off. Feet may also swell and redden.

Ringtail is traditionally attributed to low environmental humidity and high temperature, although a number of other possible causes have been suggested, from dietary deficiencies (low levels of fatty acids) to genetic predisposition. For lab and pet rodents, poor bedding (i.e., overly absorbent bedding) or repeated blood draws from tail veins have also been identified as possible causes of ringtail.

The cause of feline hyperesthesia syndrome is unknown. Some experts believe FHS to be a form of epilepsy, while others believe it is a behavioural disorder triggered by trauma. Noting that affected cats tend to be dominating rather than submissive, some research argues that FHS is conflict displacement in which the cat acts out thwarted territorial disputes on its own body.

Although any age, breed, or sex of cat can develop feline hyperesthesia syndrome, those most susceptible include the Siamese, Burmese, and Himalayan breeds.

A number of different conditions can cause pain in the general area of the coccyx, but not all involve the coccyx and the muscles attached to it. The first task of diagnosis is to determine whether the pain is related to the coccyx. Physical rectal examination, high resolution x-rays and MRI scans can rule out various causes unrelated to the coccyx, such as Tarlov cysts and pain referred from higher up the spine. Note that, contrary to most anatomical textbooks, most coccyxes consist of several segments: 'fractured coccyx' is often diagnosed when the coccyx is in fact normal or just dislocated at an intercoccygeal joint.

A simple test to determine whether the coccyx is involved is injection of local anesthetic into the area. If the pain relates to the coccyx, this should produce immediate relief.

If the anesthetic test proves positive, then a dynamic (sit/stand) x-ray or MRI scan may show whether the coccyx dislocates when the patient sits.

Use of dynamic x-rays on 208 patients who gave positive results with the anesthetic test showed:

- 31% Not possible to identify the cause of pain

- 27% Hypermobility (excessive flexing of the coccyx forwards and upwards when sitting)

- 22% Posterior luxation (partial dislocation of the coccyx backwards when sitting)

- 14% Spicule (bony spur) on the coccyx

- 5% Anterior luxation (partial dislocation of the coccyx forwards when sitting)

This study found that the pattern of lesions was different depending on the obesity of the patients: obese patients were most likely to have posterior luxation of the coccyx, while thin patients were most likely to have coccygeal .

Wet-tail or proliferative ileitis, is a disease of hamsters. It is precipitated by stress. Even with treatment, the animal can die within 48–72 hours. Baby hamsters are much more likely to get the disease than older hamsters. It commonly is found when the hamster is being weaned at about four weeks of age.

Only a few individuals who did not have fatal kidney and bladder complications are known to have survived beyond birth with this condition.

It is suggested that the diagnostic criteria for Malpuech syndrome should include cleft lip and/or palate, typical associated facial features, and at least two of the following: urogenital anomalies, caudal appendage, and growth or developmental delay.

Due to the relatively high rate of hearing impairment found with the disorder, it too may be considered in the diagnosis. Another congenital disorder, Wolf-Hirschhorn (Pitt-Rogers-Danks) syndrome, shares Malpuech features in its diagnostic criteria. Because of this lacking differentiation, karyotyping (microscopic analysis of the chromosomes of an individual) can be employed to distinguish the two. Whereas deletions in the short arm of chromosome 4 would be revealed with Wolf-Hirschhorn, a karyotype without this aberration present would favor a Malpuech syndrome diagnosis. Also, the karyotype of an individual with Malpuech syndrome alone will be normal.

Sirenomelia, alternatively known as Mermaid syndrome, is a rare congenital deformity in which the legs are fused together, giving them the appearance of a mermaid's tail as the nickname suggests.

This condition is found in approximately one out of every 100,000 live births (about as rare as conjoined twins) and is usually fatal within a day or two of birth because of complications associated with abnormal kidney and urinary bladder development and function. More than half the cases of sirenomelia result in stillbirth and this condition is 100 times more likely to occur in identical twins than in single births or fraternal twins. It results from a failure of normal vascular supply from the lower aorta in utero. Maternal diabetes has been associated with caudal regression syndrome and sirenomelia, although a few sources question this association.

VACTERL-H is an expanded form of the VACTERL association that concludes that this diagnosis is a less severe form of sirenomelia. The disorder was formerly thought to be an extreme case of caudal regression syndrome; however, it was reclassified to be considered a separate condition.

Patients show markedly low immunoglobulin levels of IgG, IgA, and IgM.

Many small mammals are able to induce degloving of their tails to escape capture; this is comparable to tail autotomy in reptiles.

A remedy, which can work within hours, perhaps by countering constipation, is to feed green pea to affected fish. Fish surgeons can also adjust the buoyancy of the fish by placing a stone in the swim bladder or performing a partial removal of the bladder.

Activities that put pressure on the affected area are bicycling, horseback riding, and other activities such as increased sitting that put direct stress on the coccyx. The medical condition is often characterized by pain that worsens with constipation and may be relieved with bowel movement. Rarely, even sexual intercourse can aggravate symptoms.

Swim bladder disease, also called swim bladder disorder or flipover, is a common ailment in aquarium fish. The swim bladder is an internal gas-filled organ that contributes to the ability of a fish to control its buoyancy, and thus to stay at the current water depth without having to waste energy in swimming. A fish with swim bladder disorder can float nose down tail up, or can float to the top or sink to the bottom of the aquarium.

Many of the congenital malformations found with Malpuech syndrome can be corrected surgically. These include cleft lip and palate, omphalocele, urogenital and craniofacial abnormalities, skeletal deformities such as a caudal appendage or scoliosis, and hernias of the umbillicus. The primary area of concern for these procedures applied to a neonate with congenital disorders including Malpuech syndrome regards the logistics of anesthesia. Methods like tracheal intubation for management of the airway during general anesthesia can be hampered by the even smaller, or maldeveloped mouth of the infant. For regional anesthesia, methods like spinal blocking are more difficult where scoliosis is present. In a 2010 report by Kiernan et al., a four-year-old girl with Malpuech syndrome was being prepared for an unrelated tonsillectomy and adenoidectomy. While undergoing intubation, insertion of a laryngoscope, needed to identify the airway for the placement of the endotracheal tube, was made troublesome by the presence of micrognathia attributed to the syndrome. After replacement with a laryngoscope of adjusted size, intubation proceeded normally. Successful general anesthesia followed.

A rare follow-up of a male with Malpuech syndrome was presented by Priolo et al. (2007). Born at term from an uneventful pregnancy and delivery, the infant underwent a surgical repair of a cleft lip and palate. No problems were reported with the procedure. A heart abnormality, atrial septal defect, was also apparent but required no intervention. At age three years, mental retardation, hyperactivity and obsessive compulsive disorder were diagnosed; hearing impairment was diagnosed at age six, managed with the use of hearing aids. Over the course of the decade that followed, a number of psychiatric evaluations were performed. At age 14, he exhibited a fear of physical contact; at age 15, he experienced a severe psychotic episode, characterized by agitation and a loss of sociosexual inhibition. This array of symptoms were treated pharmocologically (with prescription medications). He maintained a low level of mental deficiency by age 17, with moments of compulsive echolalia.

There are four levels (or "types") of malformation. The least severe indicates partial deformation (unilateral) of the sacrum. The second level indicates a bilateral (uniform) deformation. The most severe types involve a total absence of the sacrum.

Depending on the type of sacral agenesis, bowel or urinary bladder deficiencies may be present. A permanent colostomy may be necessary in the case of imperforate anus. Incontinence may also require some type of continence control system (e.g., self-catheterization) be utilized. Occasionally if deformities of the knees, legs or feet would prove unresponsive to corrective action, amputation at the knee may be proposed.

Before more comprehensive medical treatment was available, full amputation of the legs at the hip was often performed. More recently, the 'amputation' (actually a disarticulation because no cutting of the bone is involved) is done at the knee for those who have bent knee positions and webbing between thigh and calf to enable more ease of mobility and better seating. Some children with knee disarticulation use prosthetic legs to walk. Prosthetics for children without substantial hip and trunk control is usually abandoned in favor of faster and easier wheelchair mobility as the child's weight and age increases. Children may 'walk' on their hands and generally are able to climb and move about to accomplish whatever they need and want to accomplish. Children more mildly affected may have normal gait and no need for assistive devices for walking. Others may walk with bracing or crutches.

There is typically no cognitive impairment associated with this disability. Adults with this disability live independently, attend college, and have careers in various fields. In 2012, Spencer West, a man with sacral agenesis and both legs amputated, climbed Mt. Kilimanjaro using only his hands.

Heterotopy in molecular biology is the name given to the expression or placement of a gene product from what is typically found in one area to another area. It can also be further expanded to a subtle form of exaptation where a gene product used for one underlying purpose in a diverse group of organisms can re-emerge repeatedly to produce seemingly paraphyletic distributions of traits. But actual phylogenetic analysis supports a monophyletic model as does evolutionary theory. Heterotopy is used to explain this and there are so commonly cited examples.

An example is chitin a very durable structural protein used in surgical sutures as well as durable varnishes but is common to many animals especially crustaceans and insects. But is also found in the African clawed frog ("Xenopus laevis").

Wagner et al., suggest that chitin might have a microscopic function observed in cell to cell signaling and the manufacture of insect cuticle for example might represent a recurrent change in the location of expression chitin

Speculative, but however Chitin synthase is maintained in many lineages where it does not have an obvious macroscopic function.

It is thought that because so many organisms share such a profound degree of genetic and molecular similarity that shifts in the location of expression might be a regular occurrence throughout time.

Molecular analysis shows that proteins that seem to have a single specific function are instead found in many different tissue types. One example of this phenomenon is crystallin, a clear protein that makes up the lens of the eye; it is also has structural functions in the heart.