The aims of the present study were (a) to maintain the structure and function of the small intestine of the piglet after weaning, and (b) to compare the capacity in vivo of sucking and weaned piglets to digest oral boluses of lactose and sucrose and absorb their monosaccharide products. Piglets were fed on cows' whole milk ad libitum every 2 h for 5 d after weaning. Physiological doses of lactose plus fructose (treatment LAC + FRU) and sucrose plus galactose (treatment SUC + GAL) were administered on day 27 of lactation and on the fifth day after weaning, after which time piglets were killed. Villus height and crypt depth were maintained (P > 0.05) by feeding cows' milk after weaning. The areas under the curves (AUC) for galactose and glucose, adjusted for live weight and plasma volume, increased (P < 0-05) after weaning. Despite the enhancement of gut function after weaning, the galactose index (Gall: AUC for galactose ingested as lactose divided by the AUC for the same dose of galactose ingested as the monosaccharide) and fructose index (FruI: AUC for fructose ingested as sucrose divided by the AUC for the same dose of fructose ingested as the monosaccharide), which are indices of digestive and absorptive efficiency, both decreased after weaning. This apparent anomaly may be reconciled by increased growth, and hence surface area, of the small intestine between weaning and slaughter such that 'total' digestion and absorption most probably increased despite apparent decreases in GalI and FrnI.Positive correlations (P < 0.05) between villus height and GalI are consistent with the maximum activity of lactase occurring more apically along the villus. Significant linear relationships (P < 0.05) were recorded between villus height at the proximal jejunum and adjusted AUC for galactose and glucose following treatment LAC + FRU, and between villus height at the proximal jejunum and adjusted glucose AUC following treatment SUC + GAL. These relationships suggest that maximum digestion and absorption occurs at increasing distances along the crypt:villus axis in the weaned pig.

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In an effort to determine the sterol precursor(s) of the 28-carbon ecdysteroid, makisterone A, honey bee pupae (13 days post-oviposition) were injected with radiolabeled sterols and subsequently examined for labeled ecdysteroids. High performance liquid chromatography of the pupal extracts [14C]sitosterol into an ecdysteroid was observed. The neutral sterols of uninjected honey bee pupae contained 49.8% 24methylenecholesterol on a relative percent basis and, with three other CZ8 and C29 sterols, accounted for over 99% of the total sterols present.

No abstract

Both casein and yeast hydrolysate contain feeding stimulants for the adult female house fly. Guanosine monophosphate is the major active component in yeast hydrolysate. Several amino acids, including leucine, methionine, lysine, and isoleucine, are also effective feeding stimulants and are presumed to be the active components in the casein hydrolysate. Solution in phosphate buffer is necessary in all instances to obtain maximum activity with the stimulants.