01-05-2016, 04:54 PM
French Molt: Diagnosis, Prevention and Control
Diagnosis, Prevention, and Control of French Molt
Gary D. Butcher and Richard M. Miles
French molt is an important disease of young budgerigars characterized by abnormal feathering. The condition has occasionally been reported in young lovebirds and other psittacine species. The name "French molt" was used because the disease frequently affected offspring of budgerigars that had been imported into Germany from France.
Clinical signs of French molt usually appear about five to six weeks of age when the young birds are ready to leave the nest. Excessive molting and occasional breakage of wing and tail feathers occur at this time or shortly after the birds have been flying for a few days. The degree of feather loss reflects the severity of the disease. In severe cases, the secondary flight feathers (shorter, upper "arm" feathers) are also lost while in the most severe cases, nearly all body feathers are shed. Since affected birds are usually unable to fly, they are known as "runners", "creepers", or "crawlers".
There appears to be a pattern to the feather loss. The most medial flight feathers drop out first, and they are shed symmetrically from both wings. Often, all except the two outermost primary flight feathers are lost. These feathers are the first to develop and complete their growth. Only developing feathers which are still growing are lost during an attack of French molt. This is evidenced by the appearance of dried blood spots at the sites where the feathers have fallen out.
Microscopically there is no evidence of dermatitis. The keratin of the quills is poorly developed, and there is extensive hemorrhage in the vascular pulp of the quills. The growth rate of the flight feathers is reduced.
French molt is sporadic in occurrence. The disease may appear suddenly in an aviary and affect offspring of breeding pairs at random. Individual nests may contain both affected and normal fledglings. Affected young within a nest show varying degrees of severity. Generally, after the disease appears, it continues throughout the breeding season, especially in breeding pairs which have already reared two nests of offspring.
The etiology of French molt is still a matter of speculation. Many possible causes have been postulated. These include:
a nutritional deficiency or imbalance such as a protein or amino acid deficiency* in the proventricular secretions of the nursing adults:
a papovavirus infection; and
a budgerigar pox virus infection.
The info about nutrition added by Avianweb:
*Dietary: Poor feather condition / long molts and flaky beaks may be the result of a diet deficient in the essential amino acid "methionine." The requirement for methionine tends to increase when accumulated levels of toxic substances in the body increase.
High levels of methionine can be found in sesame seeds, pumpkin seeds, sunflower seeds, Brazil nuts, fish, meats, eggs, as well as various lentils. Significant amounts can also be found in spinach, potatoes and boiled corn.
Supplementation is another option for birds that don't have access or refuse to eat foods rich in methionine - such as spirulina, which is rich in this amino acid.
Once nutritional needs are met, it may take 9 to 12 months for new, better feathering and the flaky beak to be replaced with a new, smooth one.
While the actual cause of French molt is unknown, certain factors tend to increase the incidence and severity of the condition. These include:
stress due to overbreeding, early breeding or out-of-season breeding;
selection of birds for show at the expense of health;
infectious agents, dietary deficiencies and environmental stresses acting in concert;
strains with a history of French molt;
the use of artificial lights to induce breeding during the normal off season.
Since there is no known cause for French molt, there is no specific recommended therapy.
supplementation of animal protein and vitamins in the diet of breeders;
pulling abnormal and loose feathers to stimulate replacement;
limit breeding to two clutches per breeding pair per year; and
selection against French molt in the breeding program.
Affected birds sometimes recover spontaneously at the first molt within 6 to 8 months of age; however, severely affected birds may never develop normal plumage.
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U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. and M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Larry Arrington, Dean.
Source: edis.ifas.ufl.edu - University of Florida
Copyright Information: This document is copyrighted by the University of Florida, Institute of Food and Agricultural Sciences (UF/IFAS) for the people of the State of Florida. UF/IFAS retains all rights under all conventions, but permits free reproduction by all agents and offices of the Cooperative Extension Service and the people of the State of Florida. Permission is granted to others to use these materials in part or in full for educational purposes, provided that full credit is given to the UF/IFAS, citing the publication, its source, and date of publication
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Last edited by FaeryBee; 06-11-2017 at 08:14 PM.