APPLICATION OF AGAR-FILL METHOD TO ESTIMATE COMPARTMENT CAPACITY OF GASTROINTESTINAL-TRACT IN SYRIAN-HAMSTERS (MESOCRICETUS-AURETUS)

In the present study we have developed the agar-fill method for the me asurement of gastrointestinal-tract capacity (GTC) to replace the in v itro water-fill method. This would estimate GTC without using complex equipment and techniques, and can be applied to the measurement of GTC for small laboratory animals. We attempted to confirm the efficiency of the agar-fill method by investigating the relationship between diet ary neutral-detergent fibre (NDF) content and GTC. The digestion trial s were carried out using the Syrian hamster (Mesocricetus auretus). Th e trials were conducted using both sexes, two age-groups and three lev els of dietary NDP with a cross-classified design. The size of each ga strointestinal organ was determined as tissue weight (TW) and GTC. The DM intake, digestible DM intake, DM digestibility, NDF digestibility, acid-detergent fibre (ADF) digestibility and digesta transit time wer e also measured. GTC increased with increasing NDF content of the diet s. TW responded similarly to increasing NDF content, but the response was smaller than that of GTC. DM digestibility decreased with increasi ng NDF content of the diet. The digestible DM intake did not decrease with increasing NDF because DM intake increased with NDF content. Dige sta transit time was not shorter of the high-NDF-diet group but DM int ake increased with increasing NDF content. NDF digestibility did not d iffer significantly between low- and medium-NDP diets. ADF digestibili ty was low in the low-NDF-diet group. The digestion characteristics we re highly correlated with TW and GTC, except for TW of small intestine . These correlations were higher with GTC than with TW. The results of the present study confirm previous findings suggesting that the agar- fill method is a useful means of estimating GTC for small laboratory a nimals.