Dietary Inclusion of Monosodium Glutamate in Gestating and Lactating Sows Modifies the Preference Thresholds and Sensory-Motivated Intake for Umami and Sweet Solutions in Post-Weaned Pigs

SIMPLE SUMMARY: Umami is an innately hedonic taste in pigs, which has been related to glutamic acid (i.e., monosodium glutamate (MSG)) and other dietary amino acids. We studied the inclusion of 5% MSG in gestating and lactating sow diets, with the objective of altering feeding behavior of the progeny. It was observed that the addition of MSG to maternal diets decreased the preference thresholds for umami and sweet tastants in the progeny, and increased sucrose sensory-motivated intake. In contrast, MSG supplementation decreased MSG-motivated intake and did not modify the total consumption and consumption patterns of pigs for these solutions. We concluded that MSG inclusion in maternal diets modifies feeding behavior in pigs in what appears to be a compensatory mechanism to balance the diet for basic nutrients. ABSTRACT: Pigs show an innate preference for umami (monosodium glutamate, MSG) taste. Nevertheless, the influence of a pre and postnatal umami exposure remains unclear. An experiment was conducted to test the hypothesis that MSG inclusion into maternal diets would modify the feeding behavior of post-weaning pigs. A total of 22 sows were selected on day 85 of gestation and randomly assigned to one of two gestating and lactating programs (standard commercial diets without or with 50 g/kg of MSG). Later, 208 pigs born from these sows were selected to evaluate their preference thresholds, sensory-motivated intake, total consumption, and consumption patterns for MSG and sucrose solutions. Pigs born from MSG-fed sows showed lower (p < 0.045) preference thresholds for MSG and sucrose than did animals born from control sows, and displayed an increased (p < 0.050) sensory-motivated intake for sucrose and decreased for MSG. Conversely, no differences (p > 0.05) were observed in the total consumption or consumption patterns of MSG or sucrose solutions among pigs born from control and MSG-fed sows. It is concluded that the feeding behavior of nursery pigs can be influenced by pre and postnatal inclusion of a taste active compound into maternal diets. It would appear that a compensatory mechanism to balance dietary nutrients might be in place.