Effect of resistant starch on the intestinal health of old dogs: fermentation products and histological features of the intestinal mucosa.

The effects of resistant starch (RS) intake on nutrient digestibility, microbial fermentation products, faecal IgA, faecal pH, and histological features of the intestinal mucosa of old dogs were evaluated. The same formulation was extruded in two different conditions: one to obtain elevated starch cooking degree with low RS content (0.21%) and the other lower starch cooking with high RS content (1.46%). Eight geriatric Beagles (11.5 ± 0.38 years old) were fed each diet for 61 days in a crossover design. Food intake, nutrient digestibility, fermentation products, faecal pH, and faecal IgA were examined via variance analysis. Histological results of intestinal biopsies were assessed via Wilcoxon test for paired data. The morphometric characteristics of large intestine crypts were evaluated via paired t tests (p < .05). Protein, fat, and energy digestibilities were higher for the low-RS diet (p < .05). Dogs receiving the high-RS diet had lower faecal pH and higher values for propionate, butyrate, total volatile fatty acids, and lactate (p < .05). No differences between diets were found in the histological parameters of the gut mucosa, and only a tendency for deeper crypts in the descending colon was observed for dogs fed the high-RS diet (p = .083). The intake of a corn-based kibble diet manufactured with coarse ground raw material and low starch gelatinization to obtain 1.4% of RS affected microbial fermentation products and faecal pH and tended to increase crypt depth in the descending colon of old dogs.

Beet pulp intake and hairball faecal excretion in mixed-breed shorthaired cats.

Hairball formation may induce vomiting and intestinal obstruction in predisposed cats. Some insoluble fibres as sugarcane fibre and cellulose can prevent hairball formation. The aim of this study was to evaluate the effect of beet pulp consumption, a moderate soluble and fermentable fibre source, on faecal trichobezoars excretion in adult shorthaired cats fed kibble diets. Eighteen mixed-breed shorthaired cats and three extruded diets were used as follows: a basal diet without added fibre source (PB0-8.8% dietary fibre); BP8-8% inclusion of beet pulp (17.5% of dietary fibre); BP16-16% inclusion of beet pulp (23.8% of dietary fibre). The cats were fed during 31 days and faeces quantitatively collected during three periods of 3 days each (from days 3-5; 15-17; 26-28). Gastrointestinal transit time was determined in the last 3 days of study (from days 29-31). The trichobezoars were separated from faeces, collected, dried and washed in ether for complete removal of all faecal material. The results were submitted to repeated-measure analysis of variance and means evaluated by polynomial contrast (p < 0.05). Beet pulp increased faecal production (p < 0.001) and reduced gastrointestinal transit time (p = 0.003). No alterations were found on trichobezoar faecal excretion, both as considered in number per cat per day of mg per cat per day (p > 0.05). Beet pulp intake did not reduce the number or the size of hairballs eliminated via faeces of shorthaired cats.

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.