Parâmetros de fermentação in vitro de alimento extra-usado de duas raças de cães (Buldogue francês e Whippet) E WHIPPET)

Abstract

The aim of this study was to evaluate the in vitro fermentation parameters of a dry extruded complete food using dogs of two breeds, one brachycephalic and the other dolichocephalic. Twelve adult dogs were used, 6 French Bulldogs (FB) and 6 Whippets (W), submitted to fresh feces collection for 3 consecutive days. Fresh feces were incubated at 39°C under anaerobic conditions and the same extruded food supplied to the dogs, submitted or not to pre-digestion, was used as substrate. The evaluation followed a 2x2 factorial design with two breeds of dogs (FB and W) and two substrates (food with and without enzymatic treatment). Gas production was recorded for 48 hours and the disappearance of organic matter (OMD) and dry matter (DMD) was calculated by weight difference. The remaining liquid was collected and analyzed for pH and concentration of volatile fatty acids, lactic acid and N-NH3. Fresh feces were also used to determine pH, DM and fecal score, as well as final fermentation products to study the correlation with in vitro data. Substrate pre-digestion resulted in lower DMD, cumulative gas volume and maximum fermentation rate (p<0.05). However, the time to reach half of the asymptote was increased by 1h (p<0.05). Untreated substrate resulted in lower pH and higher concentration of lactic acid and short chain fatty acids. Inoculum FB showed higher fermentation activity, represented by higher DMD and gas production (p<0.05). Higher concentrations of N-NH3, lactic acid and volatile fatty acids were found using FB inoculum (p<0.05), with a tendency (0.05<p<0.10) of a lower pH value. Whippet breed dogs had drier feces and lower ammonia concentration (p<0.05). Fecal score and pH did not differ between breeds, as did the concentrations of VFA and lactic acid in feces (p>0.05). The previous enzymatic treatment changed the substrate fermentation kinetics and FB dogs seem to have a intestinal microbiota that leads them to a greater production of in vitro gas and nitrogen compounds related to malformation and fecal odor.