MOI.I.USCUM CONTAGIOSUM IN BIRDS. 



Synonyms. Epithelioma Contagiosum ; Acne Varioliforma ; 

 Acneoid Epithiliosis ; Bird-pox ; Gefliigelpocken. 



Definition. A croupous or diphtheritic inflammation of the 

 mucosa and skin due to an invisible, infinitesimal, filtrable 

 microbe. 



Contagion. This affection is virulently contagious to pigeon, 

 chicken and goose, and is easily transferred by rubbing the mor- 

 bid products on the delicate skin of the comb, wattles, eyelids, 

 beak, etc., or on the buccal or nasal mucosa. In such an ex- 

 posed situation the raw surface becomes the seat of accidental 

 microbian infection, and the disease has been attributed to proto- 

 zoa (gregarina, coccidia, blastomycetes). The experiments of 

 Marx and Sticker (1902) have, however, definitely shown that 

 the virulent material passes through a Berkefield filter though it 

 is arrested by the finest porcelain filter. This ranks it with the 

 invisible microbes of rabies, lung plague, etc., the demonstra- 

 tion of which under the microscope is not yet accomplished. It 

 has great vitality and resistance, having survived complete drying 

 at room temperature ; exposure to sunlight or to 8° F. for one 

 week ; three hours at 140° F. ; or one week in glycerine. It 

 perishes in two per cent carbolic acid. Passed from the pigeon 

 through the system of the hen, it parts with its virulence for the 

 pigeon. 



Recovery from a first attack brings immunity against a second. 



Symptoms. These resemble those of chicken diphtheria. In 

 slight attacks there is inflammation with more or less production 

 of false membrane in the mouth, nose, throat and eyes and at 

 times in the bowels causing diarrhoea. When it extends to the 

 skin, warty-like masses appear oh the angles of the beak, nasal 

 openings, eyelids, ears, comb, wattles or bare parts of the head, 

 at first the size of poppy seed or millet seed, and later of a hemp 

 seed, or even a pea, or cherry stone, imbilicated in the centre, un- 

 like an ordinary wart, and of a variable color, reddish or yellowish 

 gray or brown, and even in some recent cases, a pearly lustre. 

 The individual nodule is definitely circumscribed and is easily 

 enuncleated by pressure between finger and thumb, the contents 

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