Effects of consuming diets containing various fats or citrus flavanones on plasma lipid and urinary F2-isoprostane concentrations in overweight cats.

OBJECTIVE: To compare in overweight cats the effects of feeding moderate-energy diets with moderate fat content but with saturated fat (beef tallow), saturated fat plus citrus flavanones, or monounsaturated fat (olive oil) on plasma lipids and urinary F2-isoprostane concentrations. ANIMALS: 20 overweight cats with mean+/-SD body weight of 5.2+/-0.2 kg and mean body condition score of 7.8+/-0.2 (9-point scale). PROCEDURES: Body weight, plasma total cholesterol and triacylglycerol concentrations, and urinary F2-isoprostane concentration (as marker of oxidative stress) were measured at the beginning of the study, when the cats were fed a maintenance diet, and after 1, 3, and 5 months of consuming test diets. RESULTS: In overweight cats, citrus flavanones supplementation of the saturated fat diet was associated with lower energy intake and with lower plasma lipids and urinary F2-isoprostane concentrations than in cats fed the saturated fat alone. Monounsaturated fat feeding resulted in lower food intake than in cats fed saturated fat. However, plasma lipids concentrations remained within reference limits throughout the study. CONCLUSIONS AND CLINICAL RELEVANCE: Although the clinical relevance of these findings is unknown, the significant differences detected indicated that lower energy intake with citrus flavanones supplementation or with substitution of saturated fat for monounsaturated fat could be good strategies for decreasing plasma lipids concentration and oxidative stress in overweight cats, even before considerable loss of body weight is observed.

Fat digestibility is reduced in old cats with subnormal cobalamin concentrations.

Fat digestibility is decreased in old cats for unknown reasons. Subclinical gastrointestinal diseases and pancreatic dysfunction, both related to ageing, can affect food digestibility. The aim of the present study was to elucidate the prevalence of subnormal cobalamin concentration and pancreatic disease in old cats and study the relationship between both markers and fat digestibility. A total of sixty-four cats without evident signs of gastrointestinal disease were included and grouped according to age: (1) fifteen middle-aged (MA), aged 3-7 years; and (2) forty-nine old, aged 10-17 years. All cats were tested for serum cobalamin, specific feline pancreatic lipase (fPL) and feline trypsin-like immunoreactivity. Then, sixteen of the old cats were selected and grouped according to cobalamin and fPL concentrations: control (normal cobalamin and fPL); low vitamin B12 (cobalamin <290 ng/l; normal fPL); and high fPL (normal cobalamin; fPL >4 µg/ml). A food digestibility trial with a high-fat diet (21·6 %) was performed. In the old group, cobalamin was lower and fPL higher than in MA cats. Of the old cats (n 49), 14 % had subnormal cobalamin, 8 % had a severe increase in fPL, 2 % had both alterations and 14 % had a slight increase in fPL. By contrast, MA cats did not have cobalamin deficiency or an increase in fPL concentrations. Fat digestibility was lower in low vitamin B12 cats than control cats. Decreased fat digestibility is not present in all old cats but could be a characteristic of subclinical chronic gastrointestinal disease. Cobalamin concentration, as a marker of gastrointestinal disease, could be useful for the routine evaluation of old cats.