Objectives -To compare serum concentrations of homocysteine (Hcy) in dogs fitting the criteria for the systemic inflammatory response syndrome (SIRS) and healthy dogs, and compare these values to commonly measured B-vitamins.Methods -Study dogs were classified into noninfectious SIRS or sepsis groups and blood was drawn on Day 1 of the patient's hospitalization for the measurement of Hcy, folate and cobalamin concentrations. Hcy was measured in 51 clinically normal dogs to serve as the control group.Results -A statistically significant difference was found between the Hcy concentrations of the healthy group when compared to noninfectious SIRS and sepsis groups. Hcy values were not correlated with folate, cobalamin or APPLE fast severity scores. Hcy concentrations were significantly lower in sick dogs when compared to the control group, which is dissimilar to the human population.Clinical Significance -The clinical significance of Hcy changes in critically ill dogs is currently unknown.

1. The effects of riboflavin deficiency on growth, whole-body oxygen consumption, cytochrome c oxidase (EC 1.9.3.1) activity and GDP-binding capacity of brown adipose tissue were measured in three groups of rats: sucking pups, weanling rats, and dams. Control groups were weight-matched, pair-fed or fed ad lib.2. Riboflavin deficiency reduced growth rate and increased the activation coefficient of erythrocyte glutathione reductase (NAD(P)H) (EC 1.6.4.2), as predicted. In sucking pups it also reduced whole-body O2 consumption per unit body-weight, especially after noradrenaline stimulation. In weanling rats, however, it increased O2 consumption both before and after noradrenaline stimulation.3. Cytochrome c oxidase (EC 1.9.9.1) activity of brown adipose tissue was not consistently affected by riboflavin deficiency. Binding of [3H]GDP to the mitochondria was increased in the deficient weanling rats.4. Weanling rats therefore, seemed better able to withstand the effects of severe depletion. Their reduced growth and increased non-shivering thermogenesis helped to counteract the unfavourable ratio of riboflavin: other tissuebuilding materials. The relevance for thermoregulation in riboflavin-deficient children is discussed.

Acta PrediatrScand 78: 780-781, 1989 3 12/290 321 (28)/326 (36) 290/232 286 (5.4)/290 (54) 12.0/10.8 12.2 (0.86)/12.4 (1.53) 17.0/17.4 18.0 (1.3)/16.9 (0.5) No significant differences at p<0.05, before vs. after repletion (paired t-test). Acta Paediatr Scand 78 Short communication 781 -. . lime (min) 4. Roberts SB, Coward WA, Schlingenseipen KH, Nohria V, Lucas A. Comparison of the doubly labelled water (2H2'80) method with indirect calorimetry and a nutrient-balance study for simultaneous determination of energy expenditure, water intake, and metabolizable energy-intake in preterm infants. Am J Clin Nutr 1986; 44: 315-22. 5 . Burch HB, Bessey OA, Lowry OH. Fluorimetric measurements of riboflavin and its natural derivatives in small quantities of blood serum and cells. J Biol Chem 1948; 175: 457-70.-m