IJSRST151233 | Received: 29 June 2015 | Accepted: 02 July 2015 | May-June 2015 [(1)2: 81-84] © 2015 IJSRST | Volume 1 | Issue 2 | Print ISSN: 2395-6011 | Online ISSN: 2395-602X Themed Section: Science 81 Comparison of Scanning Electron Microscopic Examination of Oats, Barley and Maize Grains with the Analyzed Degree of Starch Breakdown and Glycaemic Responses in Horses Mandy Bochnia* 1 , Sabine Walther², Hans Schenkel³, Kristin Romanowski 4 , Annette Zeyner 1 * 1 Institute of Agricultural and Nutritional Sciences, Martin-Luther-University Halle-Wittenberg, Halle, Germany 2 Institute for Geosciences Martin-Luther-University Halle-Wittenberg, Halle, Germany 3 Regional Office of Agricultural Chemistry, University Stuttgart-Hohenheim, Germany 4 Chair of Nutritional Physiology and Animal Nutrition, University of Rostock, Germany ABSTRACT Size and surface-structure of starch granules and their interconnections influence starch hydrolysis. In native grains, these factors depend mainly from the botanical origin. Previously, it has been demonstrated that microscopic examination of starch granules refers to precaecal starch digestibility. A comparison of the elevated morphological characteristics of starch granules in scanning electron microscopic pictures with the degree of starch breakdown and the glycaemic response in adult horses after feeding a defined meal offers a tool to explain differences in the responsibility to enzyme attack and starch degradation. Keywords: starch granules, scanning electron microscope, cereal grains, glycaemic response, horse I. INTRODUCTION Starch is the main carbohydrate in human and animal nutrition. The nutritional value of starch strongly depends on processing and the state of starch [1]. The glucose release as a source of energy for the body and the timeline of digestion are the major physiological properties of starch [1]. The individual botanical structure of different starch granules influences primarily the small intestinal digestibility in horses [2] and in horses the amylase activity and the capacity for starch digestion in the small intestine is very small [3]. Consequently a high small intestinal digestibility of cereal starch is the precondition for mono-gastric animals to maximize starch utilization [4]. Evidence exists that morphological properties of diverse starch granules according to scanning electron microscopy (SEM) may have a predictive value regarding the small intestinal digestibility of different starch sources in horses [2]. To our knowledge a comparison of SEM- pictures between different starch sources of cereal grain with the aid of proven labor analysis and blood parameters has not been reported before. Aim was to investigate oats, barley and maize grains by SEM and to compare obtained starch characteristics with the analyzed degree of starch breakdown (DSB) and the glycaemic response to these cereal grains measured previously in adult horses. II. METHODS AND MATERIAL Starch granules embedded in surrounding structures deriving from grains of oats (variety ‘Melody’), barley (variety ‘ACK2927’) and maize (variety ‘M_002’) were visualized by SEM (German Patent and Trademark Office; Brief disclosure for the Patent Application 10 2013 016 050.2) and further analyzed for DSB [5]. Conclusions from this were compared with the glycaemic response during the initial glucose raising period in six horses consuming meals from the same batches of cereal grains (mean of 0.8, 1.0 and 2.0 g starch/kg body weight; area under the glucose curve [AUC gluc ] up to 120 min pp. [6]. Prior to SEM, grains were crushed, spread out on a microscope slide, air dried and sputtercoated with gold. So-called secondary electron (SE) pictures were taken to characterize