80 Syiigamus. 



70.— Kitt, rath. Auat., 19()G, II, 284; Bakterienkunde, 1908, 170.— Koch, Eev. 

 f. Tk., 1883, 17.— Miiller, D. Z. f. Tin., 1889, XV, 137; 1891, XVll, 58.— Xeumann, 

 Mai. par., 1892, 562.— Nielsen, B. t. W., 1909, 212.— Plana, Clin, vet., 1906, 15.— 

 Kailliet, Zool. nied., 1895, 424.— Eeynal, Diet., II, 627.— Scheibel, D. t. W., 19o7, 

 673.— Schlegel, A. f. Tk., 1899, XXV, 137.— Schultz, A. f. Vet.-Wiss., 1901, 1117.— 

 Strose, B. t. W., 1892, 614.— Tapken, Monh., 1891, II, 241.— Zurn, Tier. Par., 

 1882, 264. 



5. Animal Parasites in the Air Passages of Fowl, 

 (a) Syngamus. (Gapes.) 



Historical. A disease caused in chickens and turkeys by Syngamus 

 trachealis was first observed in 1779 by Wiesenthal in Baltimore. It 

 has since been reported repeatedly and has been studied more care- 

 fully bv a number of observers (Leuckart, Ehlers, Railliet, ]\Iegnin, 

 Walker) . 



Occurrence. The disease which is produced by syngami 

 appears to be especially prevalent in America, England, Italy, 

 France and Germany, and it prevails preferably in enzootic or 

 epizootic distribution among pheasants bred in larger numbers 

 in captivity. Syngamus trachealis invades especially pheasants, 

 chickens, turkeys and peacocks, while Syngamus bronchialis 

 infects water fowl (geese, ducks) ; however, S. trachealis occa- 

 sionally affects other domestic birds, especially pigeons (Tossi) 

 and room birds kept in cages. Syngami have also been found 

 in partridges, American blue-jays, in cardinals, magpies, 

 rooks, swallows, wood-peckers, storks, starlings and ravens. 

 Young birds are generally affected. 



Wiesenthal estimated that the loss by syngami in the invailed parts of the 

 I'nited States amounts to 80Vv of all young chickens; Crisp states that England 

 loses annually aliout one-half million of chicks. In a large pheasant breeding 

 establishment of France there was a daily loss of 1,200 pheasants. Klee estimates 

 the loss in Germany to several hundred pheasants annually. 



Etiology. Of the genus Syngamus, belonging to the family 

 StrongylidcT, the air passages of birds are invaded ])y Synga- 

 mus trachealis Siebold (Strongylus trachealis, S. primitivus) 

 and Syngamus bronchialis Miililig. The air passages of water 

 fowl sometimes contain Monostoma flavum. 



Syngamus is a slender, red filiform worm. The head 

 contains a mouth-opening surrounded by a strong chitinous 

 ring. The posterior end of the much smaller male ter- 

 minates in a ribbed bursa which covers two spicula. The 

 female is three or four times as long as the male; its 

 posterior end is blunt, the genital pore is situated in the 

 anterior portion of the body. The male of syngamus 

 trachealis is 2-6, the female 5-20 mm. long; the male of 

 syngamus bronchialis 10 mm., the female 25 mm. The oval 

 ova (Fig. 8) are small, provided with a doulile shell. The 

 latter contains at either end a roundish opening closed liy 



Fig. 8. Ova of Synga- a delicate membrane. They contain a segmented mass or 

 mus trachealis. a <leveloped embryo. In the trachea of fowl the male and 



(Accordingto:Megnin.) female are usually found in copulation; the two look like 

 one worm, branched under an acute angle. 



Infection. Since the genital pore is closed by the adherent 

 male, the ova or the embryos develop in the body of the mother, 



