MAINTENANCE OF VILLOUS HEIGHT AND CRYPT DEPTH IN PIGLETS BY PROVIDINGCONTINUOUS NUTRITION AFTER WEANING

Thirty-rue piglets weaned at 28 days of age were used to test the hypo thesis that maintenance of nutrition after weaning would prevent rite normal decline in villous height and increase in crypt depth and hence preserve file structure and function of the small intestine. Piglets were allocated to one of four treatments at weaning: (1) control group killed at weaning; (2) piglets offered a dry starter diet ad libitum; (3) piglets offered ewes' fresh milk; and (4) piglets offered ewes' f resh milk plus 20 g L-glutamine per l. Piglets in treatments (3) and ( 4) were offered ewes' fresh milk every 2 h in a feeding schedule that increased from 1 . 2 l per piglet on the 1st day after weaning to 2 . 4 l on days 4 and 5. On the 5th day all piglets were killed and sample s of small intestine were taken for histological and biochemical exami nation. Feeding ewes' milk or ewes' milk plus 20 8 L-glutamine per l m aintained (P > 0 . 05) villous height and crypt depth compared with pi glets killed at weaning. In contrast, piglets given a dry starter diet had shorter villi (P < 0 . 001), deeper crypts (P < 0 . 001), and pro portionately 0 . 21 to 0 . 25 less protein (P > 0 . 05) in their intes tinal mucosa. Piglets given the starter diet proportionately grew from 0 . 49 to 0 . 62 more slowly (P < 0 . 02), ate the same amount of dry matter (DM; P > 0 . 05), but consumed proportionately 0 . 30 less ene rgy (P < 0 . 001) than their counterparts given the milk diets. No tre atment differences in the specific activity of lactase and sucrase wer e observed (P > 0 . 05). Significant correlations existed between volu ntary food intake and villous height at the proximal jejunum for pigle ts given the starter diet and ewes' milk (P < 0 . 05 and P = 0 . 073, respectively). In turn, villous height was significantly correlated (r = 0 . 78 to 0 . 87, P < 0 . 05) with the rate of body-weight gain aft er weaning in these two groups. For piglets offered ewes' milk plus gl utamine, an increase in DM intake was associated only with increases i n crypt depth (P < 0 . 01). These data show that the structure and fun ction of of the small intestine can be preserved when a milk diet is g iven after weaning, and suggest an association between food intake and viIlous height in determining post-weaning weight gain.