Clinicopathologic evaluation of hepatic lipidosis in periparturient dairy cattle.
BACKGROUND
Fatty change of the liver (FCL) is very common in dairy cattle periparturiently. Many laboratory methods have been implicated in order to assist the diagnosis.


OBJECTIVE
To investigate whether FCL in dairy cattle could be evaluated by assessment of ornithine carbamoyl transferase (OCT) by means of an assay modified for bovine serum, other enzyme activity, serum bile acids (SBA) concentration, or other biochemical constituents.


METHODS
A total of 187 dairy cattle were included: 106 were suspected to have liver dysfunction and were examined after referral by veterinarians; 70 were clinically healthy with mild FCL; and 11 were clinically healthy without FCL.


METHODS
Blood and liver biopsy samples were obtained after clinical examination. Histologic examination by light microscopy and classification of samples according to the severity of FCL was done, and total lipid and triglyceride concentration was measured. In serum, OCT, aspartate aminotransferase (AST), alanine aminotransferase (ALT), sorbitol dehydrogenase (SDH), glutamate dehydrogenase (GDH), alkaline phosphatase (ALP), and gamma-glutamyltransferase (gamma-GT) activity as well as SBA, glucose, ketones, total bilirubin (tBIL), and nonesterified fatty acids (NEFA) concentration were measured.


RESULTS
OCT and AST activity and tBIL concentration correlate well with the degree of FCL. SBA concentration does not contribute well to FCL diagnosis. The majority of FCL cases appeared within the first 21 days-in-milk (DIM). The majority of moderate-to-severe and severe FCL cases arose in the first 7 DIM.


CONCLUSIONS
Except for OCT, AST, and tBIL, none of the biochemical tests used, including SBA, had sufficient discriminatory power to differentiate reliably between mild and severe FCL because of poor sensitivity. A weak correlation between clinical signs and the extent of FCL was evident.
Kalaitzakis
Emmanouil
E
Clinic of Farm Animals Faculty of Veterinary Medicine, Aristotle University of Thessaloniki, Thessaloniki 541 24, Greece.
Roubies
Nikolaos
N
Panousis
Nikolaos
N
Pourliotis
Konstantinos
K
Kaldrymidou
Eleni
E
Karatzias
Harilaos
H
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000473:pathology*; D003612:Dairying; D005234:Fatty Liver / Q000473:pathology / Q000662:veterinary*; D005260:Female; D008064:Lipidoses / Q000473:pathology / Q000662:veterinary*; D008111:Liver Function Tests / Q000662:veterinary; D036801:Parturition; D011247:Pregnancy