Effect of zinc methionine on the equine hoof: an evaluation by environmental scanning electron microscopy

Abstract

THE HOOF IS A RELATIVELY SIMPLE STRUCTURE, MAINLY CONSTITUTED BY KERATIN, A HIGHLY SULFATED PROTEIN, THAT PROVIDES HARDNESS TO THE HOOF AND CERTAIN ELASTICITY TO SUPPORT THE WEIGHT AND DISTRIBUTE THE IMPACT'S INTENSITY ON THE HOOF. THE HOOF NEEDS TO HAVE AN ADEQUATE QUALITY TO BE ABLE TO CARRY OUT THESE FUNCTIONS AND THAT REQUIRES A GOOD NUTRITION BASED ON PROTEINS, VITAMINS AND MINERALS. MINERALS CONSTITUTE 4% OF BODY WEIGHT AND THEY ARE CONFORMED BY MACROMINERALS (CALCIUM, PHOSPHORUS, SODIUM, CHLORIDE, POTASSIUM, MAGNESIUM AND SULFUR) AND MICROMINERALS (SELENIUM, IODINE, COPPER AND ZINC). ZINC PARTICIPATES IN HOOF FORMATION WHILE INDUCING KERATIN PRODUCTION. ITS DIET DEFICIENCY CAUSES PROBLEMS TO THE CORNEOUS TISSUE SUCH AS: THIN AND FRIABLE HOOVES, AND FISSURES ON THE WALL. ZN MUST BE INGESTED IN CHELATED FORM, AS ZINC METHIONINE, TO BE ADEQUATELY ABSORBED. THE DIET OF SEVEN HORSES WAS SUPPLEMENTED WITH 5.4 G/DAY/HORSE OF ZINC METHIONINE FOR A PERIOD OF SIX MONTHS. SAMPLES WERE OBTAINED FROM THE WALL LEVEL AND TRANSVERSE CUTS WERE DONE; BEFORE AND AFTER THE TREATMENT, ITS MORPHOLOGY AND CONTENTS OF MINERALS (MG, CL, S, CA, NA, K, P, SI, FE, CU,ZN) WERE ANALYZED IN THE ENVIRONMENTAL SCANNING ELECTRON MICROSCOPE EQUIPPED WITH AN X RAY DISPERSER. IT WAS OBSERVED THAT THE MORPHOLOGY PRESENTED A BETTER CONSTITUTION AND COMPACTNESS OF THE TUBULAR AND INTRATUBULAR HORNS IN THE MEDIUM STRATUM, AS WELL AS A SUBSTANTIAL INCREMENT OF ZINC (32.9%) AND SULFUR (68.4%), WHICH SUGGESTS AN INCREASE IN KERATIN AND BETTER STRUCTURE OF THE HOOF.