Besnoitia darlingi

Besnoitia darlingi

<p align="CENTER"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Besnoitia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i><b>darlingi</b></i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b> (Brumpt, 1913) Mandour, 1965</b></span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>ETYMOLOGY:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Besnoitia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (for Dr. C. Besnoit) </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>darling</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (for Dr. S. T. Darling)</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>SYNONYMS:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Sarcocystis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>darlingi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Brumpt, 1913; </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Besnoitia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>panamensis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Schneider, 1965; </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Besnoitia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>sauriana</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Garnham, 1966.</span></span></span></p> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>GEOGRAPHIC DISTRIBUTION AND PREVALENCE:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> The prevalence of this parasite in cats is unknown. It has been described from naturally infected opossums (</span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Didelphis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>viginiana</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> and </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>D</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">. </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>marsupialis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">) in North and South America and from naturally infected lizards (basilisk lizards </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Basiliscus</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>basliscus</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">, </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Basiliscus</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>vittatus</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> and the borriguero lizard </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Ameiva</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>ameiva</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>praesignis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">) from South America. Only cyclic transmission between opossums and cats has been documented (Smith and Frenkel, 1977, 1984). Infection is apparently common in opossums in North America ranging from 10 to 60% (Conti-Diaz et al., 1970; Flatt et al. 1971; Smith and Frenkel, 1977).</span></span></span></p> <span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>PARASITE IDENTIFICATION:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Oocysts measure 11.8-12.8 by 10.2-12.8 </span></span></span><span style="color: #000000;"><span style="font-family: Symbol, serif;"><span style="font-size: medium;"></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">m (mean, 12.3 by 11.9 </span></span></span><span style="color: #000000;"><span style="font-family: Symbol, serif;"><span style="font-size: medium;"></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">m). No micropyle or polar granule are present. Two elliptical sporocysts are present. Sporocysts measure 6.2-8.9 by 4.8- 6.2 </span></span></span><span style="color: #000000;"><span style="font-family: Symbol, serif;"><span style="font-size: medium;"></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">m (mean, 7.9 by 5.4 </span></span></span><span style="color: #000000;"><span style="font-family: Symbol, serif;"><span style="font-size: medium;"></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">m) and do not contain Stieda bodies. Four sporozoites are present in each sporocyst and they measure approximately 5 by 2 </span></span></span><span style="color: #000000;"><span style="font-family: Symbol, serif;"><span style="font-size: medium;"></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">m. </span></span></span> <span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>LIFE CYCLE:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Oocysts are excreted by cats fed tissue cysts but not oocysts (Smith and Frenkel, 1984). The prepatent period is 9 to 14 days (mean, 11.5 days), and the patent period is 3 to 13 days (mean, 8 days). Oocysts are excreted unsporulated in the feces. Unsporulated oocysts sporulate in 2 to 3 days at room temperature (Smith and Frenkel, 1977). The location and structure of developmental stages in the cat intestine is not known. Extraintestinal development apparently does not occur in cats (Smith and Frenkel, 1984). Cats become immune to challenge infection but do not usually develop high antibody titers. Cats fed oocysts do not excrete oocysts, do not develop extraintestinal infections, do not develop measurable antibody titers, and do not become immune to challenge with tissue cysts (Smith and Frenkel, 1984).</span></span></span> <span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> It is not known if the organism named </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>B. darlingi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> in reptiles and </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>B. darlingi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> in opossums is the same species. Experimentally mice and hamsters can serve as intermediate host for </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>B. darlingi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> isolated from opossums and cats. The tissue cysts are grossly visible and are characteristic for the genera.</span></span></span> <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>CLINICAL PRESENTATION AND PATHOGENESIS: </b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> Clinical signs of infection in cats have not been reported. </span></span></span></p> <span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>TREATMENT:</b></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Besnoitia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>darlingi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> infection does not cause clinical disease in cats and no treatment is needed.</span></span></span> &nbsp; <p align="JUSTIFY"><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><b>REFERENCES:</b></span></span></span></p> <span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Conti-Diaz IA, Turner C, Tweeddale DT, Furclow ML. 1970. Besnoitiasis in the opossum (</span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Didelphis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>marsupialis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">). J Parasitol 56:457-460.</span></span></span> <span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Flatt RE, Nelson LR, Patton NM. 1971. </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Besnoitia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>darlingi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> in the opossum (</span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Didelphis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>marsupialis</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">). Lab Anim Sci 21:106-109.</span></span></span> <span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Smith DD, Frenkel JK. 1977. </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Besnoitia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>darlingi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (Protozoa: Toxoplasmatinae) cyclic transmission by cats. J Parasitol 63:1066-1071.</span></span></span> <span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;">Smith DD, Frenkel JK. 1984. </span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>Besnoitia</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"><i>darlingi</i></span></span></span><span style="color: #000000;"><span style="font-family: 'Times New Roman', serif;"><span style="font-size: medium;"> (Apicomplexa, Sarcocystidae, Toxoplasmatinae) transmission between opossums and cats. J Protozool 31:584-587.</span></span></span>