INVESTIGATIONS ON THE PRECECAL DIGESTIBIL ITY OF NATURALLY-OCCURRING THIAMIN, RIBOFLAVIN AND PANTOTHENIC-ACID

The aim of the present investigations was to produce results about pre caecal digestibility of naturally occurring thiamin, riboflavin and pa ntothenic acid from corn, wheat bran and dried skimmilk. Precaecal dig estibility is used as a quantitative measure for availability and was determined in ileorectomized growing pigs. Therefore, 6 female DL-pigs with a liveweight of about 30 kg were fitted with ileorectalanastomos is as end-to-side-anastomosis with preserved ileo-caeco-colic valve. T he metabolism trials to collect the chymus quantitatively with these a nimals were carried out from the third week until 9 weeks after surger y in the liveweight range of about 40-70 kg. Precaecal digestibilities from corn, wheat bran and dried skimmilk were for thiamin 87, 91 and 96%, respectively, with all values being significantly different. Ribo flavin was 67, 62 and 94% precaecally digestible, the significantly di fferent values for pantothenic ranged from 20 to 47 and 90%. ''Availab ility'' of native thiamin was higher than of riboflavin and pantotheni c acid, which showed the lowest value of about 50%. The availability o f the vitamins from the animal product was significantly higher than f rom vegetable products. The suitability of the method is discussed.