Effects of corn processing on the glycaemic and insulinaemic responses in horses

Abstract

This study was conducted to evaluate the effects of different corn processing techniques on the glycaemic and insulinaemic responses in horses. It was hypothesized that the changes in pre-caecal starch digestibility caused by various types of corn processing would alter the post-prandial glycaemic and/or insulinaemic response. Six horses were fed in random order: untreated, finely ground, steamed, micronized, steam-flaked and popped corn. The total corn intake was adjusted to 630 g starch/horse/day (1.2-1.5 g starch/kg BW/day). During a stabilization period of 10 days, horses also received 6 kg grass hay/horse/day. At blood collection day horses were fed their test diet (exclusively corn), and blood samples were taken at defined times. Corn feeding resulted in a significant increase in mean plasma glucose and insulin concentration, but glucose and insulin peaks as well as areas under the curve (AUC) were not clearly influenced by corn processing. The glycaemic index (in which each test diet's plasma glucose AUC was expressed relative to untreated corn) varied between 91.4 +/- 9.4% (steamed corn) and 108.4 +/- 11.8% (popped corn, treatment n.s.), the insulinaemic index (in which each test diet's plasma insulin AUC was expressed relative to untreated corn) ranged between 98.2 +/- 12.6% (steamed corn) and 121.0 +/- 29.9% (micronized corn, treatment n.s.). However, the well-established improvement in pre-caecal starch digestibility was not reflected by differences in the glucose or insulin responses.

Defatted maize germ in equine diets

“…The highest glucose and insulin levels were achieved between 2-3 hours, and 3-4 hours after feeding, respectively, in agreement with Vervuert et al (2004) and higher than the values reported by Correa et al (2016) for corn gluten 21. It is suggested that this difference may be attributed to the high starch digestibility obtained in this study.…”

Effects of feeding state on glycaemic and insulinaemic responses to a starchy meal in horses: a methodological approach

“…In horses, several studies have been conducted to describe glycaemic and insulinaemic responses to a starchy meal with a focus on grain origin (Stull and Rodiek, 1988; JoseCunilleras et al, 2004;Rodiek and Stull, 2007), different grain processing techniques (Vervuert et al, 2003(Vervuert et al, , 2004(Vervuert et al, , 2007(Vervuert et al, and 2008a or the interaction between starch and other nutrients like fiber (Stull and Rodiek, 1988;Radicke et al, 1994;Pagan and Harris, 1999;Harris et al, 2005;Vervuert et al, 2008b and2008c) or fat (Stull and Rodiek, 1988;Delobel et al, 2006). Recently, Brouns et al (2005) reviewed the influence of methodological variations and their impact on blood glucose and insulin responses to a starchy diet in humans.…”

“…In horses, the feeding states before and after feeding of the test meal is performed equivocally. In most studies, a 10-to 18-h overnight fast is described, and no additional forage was given to the horses during the postprandial blood sampling period (Stull and Rodiek, 1988;Vervuert et al, 2003Vervuert et al, , 2004Vervuert et al, , 2007Vervuert et al, , 2008aVervuert et al, , 2008bVervuert et al, and 2008cJose-Cunilleras et al, 2004;Zeyner et al, 2006). In other studies, ad libitum access to hay was offered the night before and during the blood sampling procedure (Hoffman et al, 2003;Treiber et al, 2005).…”

Creatine and maltodextrine dietetic supplementation in eventing horses at training

“…However, when horses had a diet supplemented with D-fructose, glucose or 50% fructose/ 50% glucose, no significant effect on the glucose pick concentration was observed, not even at the time of the occurrence of glucose pick (Bullimore et al, 2000). However, Vervuert et al (2004) observed that glucose plasma levels were significantly higher after glucose supplementation provided before or during the exercise and that fructose presented no advantage at all in comparison with the supply of glucose and soluble carbohydrates to endurance horses.…”