Trieliotraehelidae. 



487 



Fig. 59. Ovum of 



Trichocephalus 



affinis. 



(d) Trichotrachelidae. 



Trichina spiralis (see trichinosis) is the only one of the fili- 

 form Trichotrachelidae which is of pathologic significance. 



Trichocephali are comparatively frequent, but apparently harmless 

 inhabitants of the intestinal tract of ruminants, hogs and clogs. Their 

 anterior end is very fine and filamentous, the caudal end is much 

 thicker, cylindrical, straight in the female, rolled up in the male. The 

 small ova, (fig. 59), are lemon shaped with stopper-like formations 

 at either end. 



The following species should be mentioned: 



Trichocephalus affinis, 6 to 8 cm, long; found in the 

 cecum and small intestine of ruminants, also in the intestinal 

 tract of hogs (Meyer). 



Trichocephalus crenatus, 4 to 5 cm. long; occurs in the 

 large intestine of the hog and occasionally causes intestinal 

 catarrh. 



Trichocephalus depressiusculus, 4 to 7 cm. long; found in 

 the cecum of dogs, particularly of those that suffer from 

 dochmiasis. If present in large numbers it appears to cause 



catarrh of the cecum, occasionally also invagination (Megnin),at other times it may 

 be the cause of hemorrhagic inflammation of the colon (Miller). 



Several species of Trichosomata mth a thin anterior portion of the 

 body, gradually becoming thicker towards the caudal end, are found 

 in the intestinal tract of fowl (Tr.-longicolle, annulatum, collare, 

 tenuissimum, and ])revicolle) ; one species is found in sheep. Tr. te- 

 nuissimum occasionally occurs in the intestinal tract of pigeons, some- 

 times in very excessive numbers, and then causes profound enteritis 

 with secondary anemia with numerous fatal cases. Freese observed 

 an epizootic of severe intestinal catarrh due to Tr. retusum ; the disease 

 was generally fatal in 3 to 10 days in young chicks, and in adult 

 chickens, in 2 to 4 weeks. During the initial stage of the affection, oil 

 of anise given in 5 to 10 drop doses to a tablespoonful of olive oil, 

 proved very efficient. 



Literature. Freese, D. t. W., 1908, 715.— Klee, Vet. Jhb., 1906, 352.— Mevers, 

 Z. f. Flhyg., 1905, XIV, 157.— Miller, Am. V. Eev., 1904, 722.— Willett, O. M., 190(3, 

 366. 



(e) Whipworms in the Intestine. Oxyuriasis. 

 Etiology. The following Oxynris occur in domestic ani- 

 mals : 



1. Oxyuris equi (B. curvalis), the female 

 alone is found almost exclusively in the intestine 

 of the horse, 4 to 5 cm. long, thickened and curved 

 in front, pointed behind, mouth surrounded by three 

 lips; the male is difficult to find, 9 to 12 mm. long; 

 oval ova (fig. 60), 88 to 95 /x by 41 to 44 m, pro- 

 vided on one pole with a lid-like formation. The 

 females sometimes are up to a size of 15 cm. and 

 their phape is then changed so that the posterior 

 more slender portion is 3 or 4 times as long as the 

 anterior portion. Nitsch, Friedberger, and more re- 

 cently Jerke, have claimed that this is another species which has received tl 

 Oxyiiris mastigodes. 



2. Oxyuris vermicularis, 2 to 3 mm. long, posterior end rolled u]i, 

 9 to 10 mm. and straight. Ova oval, flat on one end, convex at the other 

 quently found in the rectum of man; according to Ziirn also in dogs. 



Fig. 60. Ova of Oxyur 



female 

 . Fre- 



