Dystocia due to a schistosomus reflexus in a miniature Dachshund


Dystocia due to a schistosomus reflexus in a miniature Dachshund 
Collen Kutzler,a Margret Root-Kustritz,a Michelle Kutzlerb

aCollege of Veterinary Medicine, University of Minnesota, St. Paul, MN 
 bCollege of Agricultural Sciences, Oregon State University, Corvallis, OR 

Schistosomus reflexus (SR) is a rare type of fetal monstrosity reported primarily in cattle, with a 
prevalence ranging from 0.01 - 1.3% of bovine dystocias.1 It has also been reported in sheep,1 goats,1 
horses,2 donkeys,3 rhinoceroses,4 and sea turtles5 but not in dogs. A 10 year old intact miniature 
Dachshund was presented with a dystocia following an unplanned mating to her great grandson. Bitch 
was clinically stable on physical examination. Small loops of fetal bowel protruded from the vulva. 
Perineal area was cleaned with an antibacterial soap and a digital examination of vestibule and vagina was 
performed. Digital palpation revealed an abnormal fetus in a ventral transverse presentation. Sterile 
lubricant was instilled into vestibule and fetus was delivered vaginally with traction. Gross fetal 
abnormalities included spinal inversion, exposure of abdominal viscera, lung and diaphragm hypoplasia, 
and limb ankyloses with positioning of the legs adjacent to the skull. Three remaining puppies were born 
without difficulty or abnormalities. Embryological mechanism by which SR develops is unknown, but it 
is reasonable to consider that the origin of this ventral wall closure defect occurred as early as after 
gastrulation. A genetic origin for SR was suggested in transforming growth factor (TGF) ß2 and TGF ß3 
knockout mice.6 In addition, the localization of transacting siRNA generating (TAS) genes to the X 
chromosome suggests that SR may be an X linked disorder.7 Despite a potential genetic origin, SR occurs 
infrequently and sporadically in domestic animals. 

Keywords: Canine, congenital, deformity, dog, fetus, midline 

References 
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donkey. J Am Vet Med Assoc 1990;197:605-607.
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Turtles (Lepidochelys olivacea). Vet Pathol 2017;54:171-177.
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embryonic lethality. Anat Embryol (Berl) 2002;206:73-83.
7. Parvari R, Welstein Y, Ehrlich S, et al: Linkage localization of the thoraco‐abdominal syndrome (TAS) gene to Xq25–26. 

Am J Med Genet 1994;49:431-434.

507 Clinical Theriogenology • Volume 11,  Number 3 • September 2019



508Clinical Theriogenology • Volume 11,  Number 3 • September 2019


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