title: Metabolic changes and induction of hepatic lipidosis during feed restriction in llamas.
abstract: OBJECTIVE
  To determine whether feed restriction induces hepatic lipidosis (HL) in llamas and to evaluate the metabolic changes that develop during feed restriction.
  
  
  METHODS
  8 healthy adult female llamas.
  
  
  METHODS
  Llamas were fed grass hay at a rate of 0.25% of their body weight per day for 13 to 28 days. Llamas were monitored by use of clinical observation, serum biochemical analyses, and ultrasound-guided liver biopsies.
  
  
  RESULTS
  All 8 llamas lost weight and mobilized fat. Five llamas developed HL, including 4 that were nursing crias. During the period of feed restriction, mean serum concentration of bile acids and activities of aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), and gamma-glutamyl transferase (GGT) were significantly higher in llamas that developed HL, compared with llamas that did not. Mean insulin-to-cortisol concentration ratios were lower in llamas with HL before and up to 7 days of feed restriction, compared with those that did not develop HL.
  
  
  CONCLUSIONS
  HL in llamas may be induced by severe feed restriction, particularly in the face of increased energy demand. Llamas with weight loss attributable to inadequate dietary intake may develop biochemical evidence of hepatopathy and HL. Increases in serum concentration of bile acids and activities of GGT, AST, and SDH may indicate the development of HL in llamas and identify affected animals for aggressive therapeutic intervention.
authors.affiliation: Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis 97331-4802, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Tornquist
authors.forename: C K
authors.initials: CK
authors.lastname: Cebra
authors.forename: R J
authors.initials: RJ
authors.lastname: Van Saun
authors.forename: B B
authors.initials: BB
authors.lastname: Smith
authors.forename: J S
authors.initials: JS
authors.lastname: Mattoon
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D001647:Bile Acids and Salts / Q000097:blood; D001707:Biopsy, Needle / Q000662:veterinary; D002161:Camelids, New World / Q000097:blood / Q000378:metabolism* / Q000502:physiology; D002784:Cholesterol / Q000097:blood; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005234:Fatty Liver / Q000097:blood / Q000209:etiology / Q000662:veterinary*; D005260:Female; D005508:Food Deprivation / Q000502:physiology*; D006854:Hydrocortisone / Q000097:blood; D007328:Insulin / Q000097:blood; D007064:L-Iditol 2-Dehydrogenase / Q000097:blood; D007774:Lactation / Q000378:metabolism; D010865:Pilot Projects; D015431:Weight Loss; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D001647:Bile Acids and Salts; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D002784:Cholesterol; D007064:L-Iditol 2-Dehydrogenase; D005723:gamma-Glutamyltransferase; D001219:Aspartate Aminotransferases; D020155:3-Hydroxybutyric Acid; D006854:Hydrocortisone