Fatal chronic liver disease

A rare liver disease occurs in Galloway cattle in Scotland, England, Canada, and the USA. The provisional name of the disease is hepatic lipodystrophy of Galloway cattle. The first cases were seen in 1965 in Scotland.¹ Subsequently, diagnosticians at the Penrith veterinary investigation center in Cumbria, England reported four cases in a small herd, all the progeny of a pedigree Galloway bull.²An overview of the cases recognized in Scotland until the late 1990 reported 15 affected calves on five farms.³ Two cases were recognized in Canada in 2000 by a diagnostician with the University of Ontario diagnostic laboratory system.^4,

5 In 2007, the disease was seen in a Galloway calf in Wyoming.

The Galloway bull calf born in Wyoming developed clinical signs of diarrhea when 6 weeks old. He was treated by a veterinarian for a suspected abomasal ulcer. Serum samples indicated biochemical evidence of hepatic and renal disease. The calf appeared to respond to treatment but by 3 months of age his condition had deteriorated. The owner noticed that the calf appeared "top-heavy", as though the development of long bones could not keep pace with muscular development. A post-mortem examination revealed a yellow and unusually firm liver (Fig. 1). Tissues examined at the Wyoming State Veterinary Laboratory by Drs. Jon Ayers and Don Montgomery had changes consistent with hepatic lipodystrophy. It is unusual to see hepatic failure in pre-weaned calves. Distinctive features of this condition are hepatic fibrosis, disorganization and loss of hepatocytes, bile ductular hyperplasia at all levels of the lobule, and osmiophilic lipid in hepatocytes and portal macrophages (Fig. 2 - 6). There were also changes in the kidney, which might be unrelated since this is not a feature in cases seen in the UK and Canada.

	Fig. 1. Sample of liver from affected calf (left) compared to that from a normal calf (right). Note yellow discoloration. The liver was diffusely fibrotic.
	Fig. 2. Low power light micrograph of liver. There is loss of lobular architecture, atrophy (or hypoplasia) of hepatocytes, and fibroplasia around presumed portal areas. HE.
	Fig. 3. Low power light micrograph of liver. In addition to features in Fig. 2, there is hyperplasia of bile ductular epithelium throughout all zones of the lobule. It is difficult to recognize normal branches of the central vein. HE.
	Fig. 4. High power light micrograph of liver. There is macrovaculation of a proportion of remaining hepatocytes (1), some of which appear to be going metaplasia into bile ductular epithelium. Vacuolation and intracytoplasmic crystal deposition is in portal macrophages (2). HE.
	Fig. 5. High power light micrograph of liver from affected calf. There is marked disruption of hepatic plate architecture. Vacuoles in hepatocytes are osmiophilic (partly extracted in this 1mm section). Note fibroplasia. TB
	Fig. 6. High power light micrograph of liver from affected calf. There are multilocular lipid-filled vacuoles in portal macrophages. TB.

Hepatic lipodystrophy is associated with failure to grow normally, lethargy and, terminally, a dull depressed Galloway calf. A serum sample will indicate evidence of hepatic failure. The oldest affected animal seen to date was 5 months. Disease sometimes results in spontaneous abortion. Nothing is known about the basis for the condition. It occurs only in Galloway and Galloway-cross cattle, which indicates it may be a genetic trait.

If you think you have seen this condition in your herd in the past, or have what may be an active case, please contact one of the individuals listed below. We are particularly interested in characterizing the disease clinically and biochemically, and in establishing whether the disease is genetic in origin.