SCINTIGRAPHIC ASSESSMENT OF GASTRIC-EMPTYING OF CANNED AND DRY DIETS IN HEALTHY CATS

Objective-To characterize factors that affect solid-phase gastric empt ying in healthy cats by use of nuclear scintigraphy and to assess diff erences in emptying patterns of dry and canned diets. Animals-20 healt hy cats. Procedure-2 groups of 10 cats each were fed dry or canned die t for at least 2 weeks before scintigraphy was done. Diets were labele d with Tc-99m-disofenin. After ingestion of labeled meals, scintigraph ic images were obtained at 0, 15, 30, 45, and 60 minutes, then every 3 0 minutes to 6 hours. Gastric emptying scans were obtained 3 times for each cat for each diet, in a complete crossover design. The T-90, T-5 0, and T-20, (times when 90, 50, and 20% of initial meal activity rema ined in the stomach, respectively) were derived from gastric emptying curves fit to nonlinear models. A mixed models approach was used for d ata analysis. Results-Gastric emptying was well described by a nonline ar model. Meal size, water intake, and diet type significantly (P < 0. 05) effected gastric emptying. The T-90, T-50, and T-20 increased with meal size, regardless of diet type or water intake. Gastric emptying of a dry diet meal took significantly (P < 0.05) longer than that of a n isocaloric meal of canned diet, except when meal size was small. Dif ferences in gastric emptying of dry and canned diets varied with the p hase (T-90 vs T-50 vs T-20) of emptying. Conclusion-Water intake, meal size, and diet type significantly influence gastric emptying in healt hy cats, and these factors must be considered in analysis of gastric e mptying data.