Mass screening of Irish wolfhound puppies for portosystemic shunts by the dynamic bile acid test

Abstract

Five hundred and sixty-six Irish wolfhound puppies aged six to 15 weeks were tested for congenital portosystemic shunts by the dynamic bile acid method. Plasma ammonia concentration was also measured in 165 of the puppies both fasting and postprandially. Nineteen puppies (3.4 per cent), nine males and 10 females, had portosystemic shunts. Smaller litters appeared to be more likely to contain affected puppies. The postprandial bile acid concentration was a reliable predictor of the presence of a shunt, with the highest concentration in a normal puppy being 38 mumol/litre and the lowest in an affected puppy being 43 mumol/litre. In contrast, fasting bile acid concentrations were normal in the majority of the affected puppies. There was considerable overlap in fasting plasma ammonia concentrations between normal and affected puppies (26 puppies, 15.8 per cent of those tested). Postprandial ammonia concentration appeared to give better separation between the two groups, apart from two individuals which produced bizarre results. It was concluded that the postprandial or dynamic bile acid test is an appropriate test for the mass screening of Irish wolfhound puppies for portosystemic shunts, and guidelines are proposed for the interpretation and follow-up of the test.

Inherited liver shunts in dogs elucidate pathways regulating embryonic development and clinical disorders of the portal vein

“…A globally used screening method measures increased pre- and postprandial serum bile acid levels (Kerr and van Doorn 1999). This test, however, gives abnormal results for many different liver diseases and is sensitive, but not specific, for congenital and acquired portosystemic shunting (Gerritzen-Bruning et al 2006).…”

“…In dogs, the closure occurs within 6–9 days (Lamb and Burton 2004). IHPSS is diagnosed almost exclusively in large-sized purebred dogs (Hunt 2004; Rothuizen and van den Ingh 1982) and a predisposition to IHPSS is suggested for Irish wolfhounds (Kerr and van Doorn 1999; Meyer et al 1995), Australian Cattle dogs (Tisdall et al 1994), Old English Sheepdogs (Lamb and White 1998), and Labrador and Golden retrievers (Tobias and Rohrbach 2003; van den Ingh et al 1995). The shunt can be anatomically positioned at the left or right side or centrally in the liver.…”

Lifespan and disease predispositions in the Irish Wolfhound: A review

“…It is, however, possible to mass screen puppies for the presence of the disease using a postprandial serum bile acid test (39). Unfortunately, this reduces the incentive for breeders to take appropriate genetic control measures to a certain degree by providing them with a means of identifying affected individuals before sale.…”

“…Onset of clinical symptoms varies, but is usually seen before one year of age (5). In Irish Wolfhounds, this condition has been reported to occur in 2.1% to 3.4% of all puppies and 18% of all litters (39,46,62). Furthermore, its prevalence in the offspring of certain individual Wolfhounds has been reported to be as high as 15% (61).…”

Evidence of Inheritance of Intrahepatic Portosystemic Shunts in Irish Wolfhounds

“…9 The observed overall prevalence of 62.5% in these test litters was much higher than could be expected based on the incidence in the entire Dutch population, which has been reported to be between 2.1 and 3.4%. 5,10 This overrepresentation with at least a factor of 20 most likely is because of the genetic make up of the parents indicating the likely hereditary nature of this defect in this breed. This is an independent confirmation of previous findings which were based on an epidemiologic study of Irish Wolfhounds.…”