Feline Tetrathyridiosis

Feline Tetrathyridiosis

<p align="CENTER"><span style="color: #000000;"><span style="font-size: large;"><b>Feline Tetrathyridiosis</b></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;"> Cats can serve as the second intermediate host of </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> spp</span></span><span style="color: #000000;"><span style="font-size: medium;"><i>.</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> It is in not known if cats develop infections with this life-cycle stage of the parasite after ingestion of the first intermediate host containing the undescribed first larval stage or only through ingestion of the second intermediate host which contains the tetrathyridium. There have been no clinical signs ascribed to this infection. In Norway, Berg &amp; Andersen (1982) discovered two tetrathyridia about 7 to 8 cm long as incidental findings in a cat during an ovariohysterectomy.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;"> The tetrathyridial stage of </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"><i>lineatus</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> has been shown capable of being collected from snakes and transferred to frogs, lizards and mice (Joyeux an Baer, 1932; Kawamoto et al., 1986). Cats have been experimentally infected with the tetrathyridial stage of </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> during attempts to complete the life cycle. Henry (1927); Witenberg (1932), and Reid &amp; Reardon (1976) infected cats with tetrathyridia recovered from the peritoneal cavity of cats or baboons and found that although some of the worms developed to the adult stage, some migrated through the intestinal wall and again take up residence as tetrathyridia within the peritoneal cavity. </span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;"> Larvae from the cat tend to be free within the peritoneal cavity and range in length from one to 7 or 8 cm. The anterior end has a scolex with four suckers that it also inverted into the body of the larva, the scolex, especially in small larvae, is in not often observed until the larva is in processed and histological-sections made. The tetrathyridia observed in the body cats by Witenberg (1932) had rather long pointed tails and were about 2 to 7 cm long. The tetrathyridia observed by Loos-Frank (1980) free in the peritoneal cavity of rodents were about 1 to 1.5 mm long and did not possess the long tails of observed on the larger larvae of Witenberg, although Witenberg also saw small compact tetrathyridial forms about 1 to 1.5 mm long encysted in the omentum of cats.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;"> When cats ingest the tetrathyridial stage, the majority of the posterior of the tetrathyridium is in lost within the gastrointestinal tract and the anterior portion which migrates through the intestinal wall to the peritoneum may regenerate the posterior body. The tetrathyridia recovered from cats apparently do not undergo asexual division within the peritoneal cavity (Conn, 1991). Dogs, in the United States and Europe, sometime develop severe peritonitis that is in due to an infection with an asexually dividing cestode that does not bear a scolex and which has been considered by some to be the larval stage of </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"><i>corti</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> (Barsanti et al., 1979), but Conn(1991) has questioned whether this form should be considered a tetrathyridial stage of </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;">. Similarly, Conn felt that the identity of the more than a thousand cestode larvae observed by Neumann (1896) in the abdominal cavity of a European cat were considered those of </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> without a good basis. Witenberg (1932) observed some very small forms encysted in the omentum of cats that were without scolices although they contained numerous calcareous corpuscles typical of tapeworm larvae.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;"><b>REFERENCES:</b></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Berg C, Andersen K. 1982. Bendelormlarver, tetrathyridier, I bukhulen hos en norsk katt. Norsk Vet 94:563-565.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Barsanti JA, Jones BD, Bailey WAS, Knipling GD. 1979. Diagnosis and treatment of peritonitis caused by a larval cestode </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> spp. In a dog. Cornell Vet 69:45-53.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Conn DB, 1991. The rarity of asexual reproduction among </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> tetrathyridia (Cestoda). J Parasitol 76:453-455.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Henry a. 1927. </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Tétrathyridium</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> et </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;">. Bull Soc Cent Ned Vet 80:147-152.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Joyeux C, Baer JG. 1932. Recherches sur les cestodes appartenant au genre </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> Villant. Bull Soc Path Exot 25:993-1010.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Kawamoto F, Fujioka H, Mizuno S, Kumada N, Voge M. 1986. Studies on the post-larval development of cestodes of the genus </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;">: shedding and further development of </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>M</i></span></span><span style="color: #000000;"><span style="font-size: medium;">. </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>lineatus</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> and </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>M.</i></span></span><span style="color: #000000;"><span style="font-size: medium;"><i>corti</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> tetrathyridia </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>in</i></span></span><span style="color: #000000;"><span style="font-size: medium;"><i>vivo</i></span></span><span style="color: #000000;"><span style="font-size: medium;">. Int J Parasitol 16:323-331.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Loos-Frank B. 1980. The common vole, </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Microtus</i></span></span><span style="color: #000000;"><span style="font-size: medium;"><i>arvalis</i></span></span><span style="color: #000000;"><span style="font-size: medium;">, as intermediate host of </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> (Cestoda) in Germany. Z Parasitenk 63:129-136.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Reid WA, Reardon MJ. 1976. </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;"> in the baboon and its development in laboratory animals. J med Primatol 5:345-352.</span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-size: medium;">Witenberg G. Studies on the cestode genus </span></span><span style="color: #000000;"><span style="font-size: medium;"><i>Mesocestoides</i></span></span><span style="color: #000000;"><span style="font-size: medium;">. Arch Zool Ital 20:467-509.</span></span></p>