Insoluble fibres, satiety and food intake in cats fed kibble diets.

Fibre is generally considered to dilute food energy, alter intestinal transit time and promote satiety; however, in cats, conflicting results have been found. In this study, two insoluble fibres were evaluated in four feline diets: control (no added fibre); diet with 10% sugar cane fibre; diet with 20% sugar cane fibre; and diet with 10% cellulose. The experiment was conducted with 32 cats, eight animals per diet, over 42 days: 1-7 for diet adaptation; 8-14 for total collection of faeces for digestibility; 15-17 for fresh faeces collection for fermentation products measurements; 18-20 for gastrointestinal transit time determination; 21 and 37 to evaluate the pattern of food intake; and 22 and 42 to assess satiety. Means were compared by analysis of variance and orthogonal contrasts, and the pattern of food intake was compared by repeated-measures analysis of variance (p < 0.05). The cats exhibited increased food intake after fibre addition to the diets (p < 0.05), achieving similar energy consumption. Cellulose and the two levels of sugar cane fibre reduced nutrient availability and energy digestibility, but only sugar cane fibre reduced fat digestibility (p < 0.05). Faecal output and the number of defecations per day increased with fibre inclusion (p < 0.05). Gastrointestinal transit time did not change with sugar cane fibre inclusion, but it was reduced with cellulose addition (p = 0.032). The pattern of food intake did not change, but cats fed fibre-supplemented diets exhibited greater consumption of a challenge meal, increasing energy intake (p < 0.01) when exposed to a palatable, energy-dense food.

Effects of food processing and fibre content on the digestibility, energy intake and biochemical parameters of Blue-and-gold macaws (Ara ararauna L. - Aves, Psittacidae).

Considering the increased incidence of obesity and metabolic diseases in caged psittacines, the effect of fibre and food processing was evaluated in the Blue-and-gold macaw. Four food formulations (0%, 7%, 14% and 21% of sugarcane fibre) processed by pelleting or extrusion were studied, resulting in eight diets. To study digestibility, 48 macaws housed in pairs in cages was used in a block design. Subsequently, diets containing 0% or 21% sugarcane fibre, pelleted or extrude was fed for 4 months to evaluate energy intake and blood metabolites. A 2 × 2 × 2 (two fibre levels, two food processing methods and two genders) factorial arrangement with subplots (beginning and end) was used. When differences were detected in anova's F test, data were submitted to polynomial contrasts in the first experiment and to orthogonal contrasts in the second experiment (p < 0.05). Fibre addition reduced protein, fat and energy (p < 0.001) digestibility in both food processing. Pelleted foods presented higher dry matter digestibility and food metabolisable energy (ME) than the extruded ones (p < 0.05). Fibre addition or the type of processing did not change ME ingestion (p > 0.05). The macaws gained body weight (p < 0.05) regardless of the diet (p > 0.05), but females fed with the high-fibre diets did not gain weight (p > 0.05), suggesting a low food ME (12.5 kJ/g).The substitution of the original diet (sunflower seeds, fruits and cooked maize) by the experimental foods decreased the basal (12-h fast) concentrations of glucose, cholesterol and triglycerides (p < 0.001). The consumption of pelleted diets reduced serum glucose and cholesterol (p < 0.05). Results suggest that the pelleted diets were more beneficial and can be used to reduce blood metabolites related to metabolic disorders that are commonly observed in macaws.

Digestibility for dogs and cats of meat and bone meal processed at two different temperature and pressure levels*.

This study evaluated the effect of two rendering processes applied to meat and bone meal (MBM) production, associated or not with extrusion, by measuring diet apparent total tract digestibility of dogs and cats, and true digestibility of amino acids (AA) by cecectomized roosters. Four diets were evaluated, with the main protein source as follows: conventional and extruded MBM; high temperature and pressure (HPT; 135 °C, 3 bar, 20 min) and extruded MBM; conventional non-extruded MBM; HPT non-extruded MBM. Nutrient digestibility and food metabolizable energy content were evaluated with dogs and cats by the method of total collection of faeces. True AA digestibility was evaluated by a precision-fed assay with cecectomized roosters. The evaluated MBM had high-ash content. The HPT process of MBM increased the digestibility of crude protein of the diets by cats, and the true digestibility of several AA by cecectomized roosters. The extrusion process did not modify the apparent total tract nutrient digestibility of MBM by dogs and their amino acid digestibility by roosters, but increased the digestibility of the dietary protein by cats. Dogs fed HPT MBM presented a higher urea post-prandial response, suggesting reductions in bioavailability and protein synthesis from absorbed AA.