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.

Angel wing, also known as airplane wing, slipped wing, crooked wing, and drooped wing, is a syndrome that affects primarily aquatic birds, such as geese and ducks, in which the last joint of the wing is twisted with the wing feathers pointing out laterally, instead of lying against the body. Males develop it more frequently than females. It has also been reported in goshawks, bustard chicks, and psittacine birds (budgerigars, macaws, and conures).

The syndrome is acquired in young birds. Due to a high-calorie diet, especially one high in proteins and/or low in vitamin D, vitamin E, and manganese, one or both carpus (wrist) joints are retarded in their development relative to the rest of the wing; for reasons unknown, if only one wing is affected, it is usually the left one. The result is a wrist which is twisted outwards and unable to perform its usual function. Angel wing symptoms include stripped remiges (flight feathers) in the wrist area, or remiges protruding from wings at odd angles. In extreme cases, the stripped feathers may resemble sickly blue straws protruding from wings. In adult birds, the disease is incurable and usually leads to an early death, as affected birds are rendered effectively or totally flightless. In young birds, wrapping the wing and binding it against the bird's flank, together with feeding the bird a more nutritionally balanced diet, can reverse the damage.

The theorized causes of angel wing are genetics, the excessive intake of carbohydrates and proteins, together with insufficient intake of vitamin E, low dietary calcium and manganese deficiency. Angel wing is occasionally observed in waterfowl residing near humans, (including domestic fowl), and the disease can sometimes be observed in areas where geese or ducks are excessively fed bread. Duck seed is an alternative for duck feeders.

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.

Surgery is an option to correct some of the morphological changes made by Liebenberg Syndrome. Cases exist where surgery is performed to correct radial deviations and flexion deformities in the wrist. A surgery called a carpectomy has been performed on a patient whereby a surgeon removes the proximal row of the carpal bones. This procedure removes some of the carpal bones to create a more regular wrist function than is observed in people with this condition.

Diplopodia is a congenital anomaly in tetrapods that involves duplication of elements of the foot on the hind limb. It comes from the Greek roots diplo = "double" and pod = "foot". Diplopodia is often found in conjunction with other structural abnormalities and can be lethal. It is more extreme than polydactyly, the presence of extra digits.

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.

Liebenberg Syndrome is a rare autosomal genetic disease that involves a deletion mutation upstream of the PITX1 gene, which is one that's responsible for the body's organization, specifically in forming lower limbs. In animal studies, when this deletion was introduced to developing birds, their wing buds were noted to take on limb-like structures.

The condition was first described by Dr. F. Liebenberg in 1973 while he followed multiple generations of a South African family, but it has since been noticed in other family lineages across the world.

In addition to history and exam, it has been recommended to perform projectional radiography of the neck, chest, shoulder, and thoracic inlet to rule out structural abnormalities such as malunited or greenstick fractures. Computed tomography (CT) or magnetic resonance imaging (MRI) are rarely indicated, but may be useful to rule out certain diagnoses if suspected, such as neurofibromatosis-related injury, intervertebral disc disorder, radiculopathy, and tumors.

In medicine, heterotopia is the presence of a particular tissue type at a non-physiological site, but usually co-existing with original tissue in its correct anatomical location. In other words, it implies ectopic tissue, in addition to retention of the original tissue type. In neuropathology, for example, gray matter heterotopia is the presence of gray matter within the cerebral white matter or ventricles. Heterotopia within the brain is often divided into three groups: subependymal heterotopia, focal cortical heterotopia and band heterotopia. Another example is a Meckel's diverticulum, which may contain heterotopic gastric or pancreatic tissue.

In biology specifically, "heterotopy" refers to an altered location of trait expression. In her book "Developmental Plasticity and Evolution", Mary-Jane West Eberhard has a cover art of the sulphur crested cockatoo and comments on the back cover "Did long crest[head] feathers evolve by gradual modification of ancestral head feathers? Or are they descendants of wing feathers, developmentally transplanted onto the head". This idea sets the tone for the rest of her book which goes into depth about developmental novelties and their relation to evolution. Heterotopy is a somewhat obscure but well demonstrated example of how developmental change can lead to novel forms. The central concept is that a feature seen in one area of an organism has had its location changed in evolutionary lineages.

Although infection of avian reovirus is spread worldwide, it is rarely the sole cause of a disease. For chickens, the most common manifestation of the disease is joint/limb lameness. Confirming infection of avian reovirus can be detected through an ELISA test by using and observing the expression of σC and σB proteins. However, isolating and identifying reoviruses from tissue samples is very time consuming. Isolation is most successfully attained through inoculation of material into chick embryo cultures or fertile chicken eggs. Inoculation of embryonic eggs through the yolk sac has shown that the virus usually kills the embryos within 5 or 6 days post inoculation. Analyzing the samples, the embryos appeared hemorrhagic and necrotic lesions on the liver were present. (Jones, Onunkwo, 1978). There have also been approaches to identify avian reoviruses molecularly by observing infected tissues with dot-blot hybridization, PCR, and a combination of PCR and RFLP. This combination allows for the reovirus strain to be typed.

People of any age may suffer from Legionnaires' disease, but the illness most often affects middle-aged and older persons, particularly those who smoke cigarettes or have chronic lung disease. Immunocompromised people are also at higher risk. Pontiac fever most commonly occurs in persons who are otherwise healthy.

The most useful diagnostic tests detect the bacteria in coughed up mucus, find "Legionella" antigens in urine samples, or allow comparison of "Legionella" antibody levels in two blood samples taken 3 to 6 weeks apart. A urine antigen test is simple, quick, and very reliable, but it will only detect "Legionella pneumophila" serogroup 1, which accounts for 70 percent of disease caused by "L. pneumophila", which means use of the urine antigen test alone may miss as many as 30% of cases. This test was developed by Richard Kohler in 1982. When dealing with "Legionella pneumophila" serogroup 1, the urine antigen test is useful for early detection of Legionnaire's disease and initiation of treatment, and has been helpful in early detection of outbreaks. However, it will not identify the specific subtypes, so it cannot be used to match the person with the environmental source of infection. The "Legionella" bacteria can be cultured from sputum or other respiratory samples. "Legionella" stains poorly with Gram stain, stains positive with silver, and is cultured on charcoal yeast extract with iron and cysteine (CYE agar).

A significant under-reporting problem occurs with legionellosis. Even in countries with effective health services and readily available diagnostic testing, about 90 percent of cases of Legionnaires' disease are missed. This is partly due to Legionnaires' disease being a relatively rare form of pneumonia, which many clinicians may not have encountered before and thus may misdiagnose. A further issue is that people with legionellosis can present with a wide range of symptoms, some of which (such as diarrhea) may distract clinicians from making a correct diagnosis.

A winged scapula due to serratus anterior palsy is rare. In one report (Fardin et al.), there was an incidence of 15 cases out of 7,000 patients seen in the electromyographical laboratory. In another report (Overpeck and Ghormley), there was only one case out of 38,500 patients observed at the Mayo Clinic. In yet another report (Remak), there were three diagnoses of serratus anterior paralysis throughout a series of 12,000 neurological examinations.

Contrary to a widespread misconception, only 3 species of bats feed on blood, and these species only live in Latin America. Common ignorance often leads to misidentification.

At the same time, the fear of bats may be naturally reinforced by the natural startle response experienced by an unsuspecting person, e.g., when a disturbed colony of bats dashes out of a cave. In fact, the majority of bats, specifically the microbats which make up the majority of species, are terrified of humans and see man as a potential predator; bats disturbed in their roost instinctively flee as fast as they can, with maternity colonies sometimes abandoning their babies since they are desperate to escape.

Often, people fear bats due to the possibility of contracting rabies, but only 0.5% of vampire bats carry rabies.

Fear of bats, sometimes called chiroptophobia (from the Greek χείρ - "cheir", "hand" and πτερόν - "pteron", "wing" referring to the order of the bats, and φόβος - "phobos", meaning "fear"), is a specific phobia associated with bats and to common negative stereotypes and fear of bats.

Schwabenhass (German for "hatred against Swabians") is a political slogan about aversion to the approximately 300,000 strong Swabian minority in Berlin. In 2013, the so-called "spätzlestreit" gained nationwide attention.

Pterygium (conjunctiva) can be diagnosed without need for a specific exam, however corneal topography is a practical test (technique) as the condition worsens.

The affected leg usually has one foot that is in an approximately normal position. The extra foot is composed of at least some metatarsal or tarsal bones and extra digits, though it is usually not complete. The feet can be joined together, so that the limb appears to have one large foot, or the extra foot can be joined to the limb separately, usually above the level of the other foot. Diplopodia affects one or both of the hind limbs.

Although the risk of Legionnaires' disease being spread by large-scale water systems cannot be eliminated, it can be greatly reduced by writing and enforcing a highly detailed, systematic water safety plan appropriate for the specific type of facility involved (office building, hospital, hotel, spa, cruise ship, etc.) Some of the elements that such a plan may include are the following:

- Keeping water temperature either above or below the range in which the "Legionella" bacterium thrives.

- Preventing stagnation, for example by removing from a network of pipes any sections that have no outlet (dead ends). Where stagnation is unavoidable, for example when a wing of a hotel is closed for the off-season, systems must be thoroughly disinfected just prior to resuming normal operation.

- Preventing the buildup of biofilm, for example by not using (or by replacing) construction materials that encourage its development, and by reducing the quantity of nutrients for bacterial growth that enter the system.

- Periodic disinfection of the system, by high heat or a chemical biocide, and the use of chlorination where appropriate.

- System design (or renovation) that reduces the production of aerosols and reduces human exposure to them, for example by directing them well away from building air intakes.

An effective water safety plan will also cover such matters as training, record-keeping, communication among staff, contingency plans and management responsibilities. The format and content of the plan may be prescribed by public health laws or regulations. There is tentative evidence for the treatment of the water with copper-silver ionization or ultraviolet light.

Mutation analysis of the "ATP7B" gene, as well as other genes linked to copper accumulation in the liver, may be performed. Once a mutation is confirmed, it is possible to screen family members for the disease as part of clinical genetics family counseling. Regional distributions of genes associated with Wilson's disease are important to follow, as this can help clinicians design appropriate screening strategies. Since mutations of the WD gene vary between populations, research and genetic testing done in countries like the USA or United Kingdom can pose problems as they tend to have more mixed populations.

As it is associated with excessive sun or wind exposure, wearing protective sunglasses with side shields and/or wide brimmed hats and using artificial tears throughout the day may help prevent their formation or stop further growth. Surfers and other water-sport athletes should wear eye protection that blocks 100% of the UV rays from the water, as is often used by snow-sport athletes. Many of those who are at greatest risk of pterygium from work or play sun exposure do not understand the importance of protection.

Diagnosis of egg allergy is based on the person's history of allergic reactions, skin prick test (SPT), patch test and measurement of egg-specific serum immunoglobulin E (IgE or sIgE). Confirmation is by double-blind, placebo-controlled food challenges. SPT and sIgE have sensitivity greater than 90% but specificity in the 50-60% range, meaning these tests will detect an egg sensitivity, but will also be positive for other allergens. For young children, attempts have been made to identify SPT and sIgE responses strong enough to avoid the need for a confirming oral food challenge.

The treatment of soft tissue parts of midface anomalies is often a reconstruction from a skin flap of the cheek. This skinflap can be used for other operations in the further, as it can be raised again and transposed again. In the treatment of midface anomalies there are generally more operations needed. Bone tissue reconstruction of the midface often occurs later than the soft tissue reconstruction. The most common method to reconstruct the midface is by using the fracture/ incision lines described by René Le Fort. When the cleft involves the maxilla, it is likely that the impaired growth will result in a smaller maxillary bone in all 3 dimensions (height, projection, width).

The majority of children outgrow egg allergy. One review reported that 70% of children will outgrow this allergy by 16 years. In subsequently published longitudinal studies, one reported that for 140 infants who had challenge-confirmed egg allergy, 44% had resolved by two years. A second reported that for 203 infants with confirmed IgE-mediated egg allergy, 45% resolved by two years of age, 66% by four years, and 71% by six years. Children will be able to tolerate eggs as an ingredient in baked goods and well-cooked eggs sooner than under-cooked eggs. Resolution was more likely if baseline serum IgE was lower, and if the baseline symptoms did not include anaphylaxis.

Vaccines are available (ATCvet codes: for the inactivated vaccine, for the live vaccine, plus various combinations).

Given that avian reovirus infections are widespread, the viruses are relatively resistant outside the host, and that vertical and horizontal transmission occurs, eradicating avian reovirus infection in commercial chicken flocks is very unlikely. In addition, absence of detectable seroconversion and failure to detect virus in cloacal swabs are unreliable indicators of resisting infection, or transmission via the egg. Thus, the most proactive and successful approach to controlling this disease is through vaccination. Since chicks are more prone to being detrimentally affected by the disease right after hatching, vaccine protocols that use live and killed vaccines are designed to provide protection during the very early stages of life. This approach has been accomplished through active immunity after early vaccination and a live vaccine or passive immunity from maternal antibodies followed with vaccination of the breeder hens. Currently, efforts toward administering inactivated or live vaccines to breeding stock to allow passive immunity to the offspring via the yolk are being taken.

The Simulator Sickness Questionnaire (SSQ) is currently the standard for measuring simulator sickness. The SSQ was developed based upon 1,119 pairs of pre-exposure/post-exposure scores from data that were collected and reported earlier. These data were collected from 10 Navy flight simulators representing both fixed-wing and rotary-wing aircraft. The simulators selected were both 6-DOF motion and fixed-base models, and also represented a variety of visual display technologies. The SSQ was developed and validated with data from pilots who reported to simulator training healthy and fit.

The SSQ is a self-report symptom checklist. It includes 16 symptoms that are associated with simulator sickness. Participants indicate the level of severity of the 16 symptoms that they are experiencing currently. For each of the 16 symptoms there are four levels of severity (none, slight, moderate, severe). The SSQ provides a Total Severity score as well as scores for three subscales (Nausea, Oculomotor, and Disorientation). The Total Severity score is a composite created from the three subscales. It is the best single measure because it provides an index of the overall symptoms. The three subscales provide diagnostic information about particular symptom categories:

- Nausea subscale is made up of symptoms such as increased salivation, sweating, nausea, stomach awareness, and burping.

- Oculomotor subscale includes symptoms such as fatigue, headache, eyestrain, and difficulty focusing.

- Disorientation subscale is composed of symptoms such as vertigo, dizzy (eyes open), dizzy (eyes closed), and blurred vision.

The three subscales are not orthogonal to one another. There is a general factor common to all of them. Nonetheless, the subscales provide differential information about participants' experience of symptoms and are useful for determining the particular pattern of discomfort produced by a given simulator. All scores have as their lowest level a natural zero (no symptoms) and increase with increasing symptoms reported.