Effect of Gamma Irradiation on Microbial Decontamination, Crude Nutrient Content, and Mineral Nutrient Composition of Laboratory Animal Diets

Document Type : Original Articles

Authors

1 Nuclear Agriculture Research School, Nuclear Science and Technology Research Institute, Karaj, Iran

2 Department of Molecular Medicine, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran

3 Cancer Biology Research Center, Tehran University of Medical Sciences, Tehran, Iran

4 Department of Research, Breeding and Production of Laboratory Animals, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization, Karaj, Iran

Abstract

Laboratory animal models are an important part of test design. Certain conditions such as microbial contamination in diets of these models could affect the results of experiments. One of the most important routes that predispose to contamination is generated through feeding of laboratory animals. This study aimed to show the effect of gamma irradiation in reducing bacteria concentrations, crude nutrient content, and concentrations of some minerals and trace elements in laboratory animal diets. Large-sized pellets with 10–15 mm diameter (commonly used for rats and hamsters) and small-sized pellets with 3–5 mm diameter (used for rabbits and guinea pigs) along with skimmed milk powder (SMP) as a food additive were exposed to gamma irradiation with different doses ranging from 3 to 30 kGy. The total microbial contamination and any possible changes in some mineral nutrient composition and the crude nutrient content were determined pre- and post-irradiation. Our data revealed that 25 kGy in pelleted diets and 18 kGy in SKM had superior effects in the reduction of bacterial contamination with little change in crude nutrient content and minerals and trace elements in nutrient requirements of laboratory animals. According to the results, gamma irradiation had minimal effects on crude nutrient content and the concentrations of some minerals and trace elements of laboratory animal diets, and it also eliminated bacterial and fungal contamination load. By using gamma irradiation, this method could yield a favorable outcome in controlling microbial contamination of animal diets.

Keywords

Main Subjects

Article Title [French]

Effet de l'irradiation Gamma sur la Décontamination Microbienne, la Teneur en Éléments Nutritifs Bruts et la Composition en Éléments Minéraux des Régimes Alimentaires des Animaux de Laboratoire

Abstract [French]

Les modèles d'animaux de laboratoire jouent un rôle important dans la conception des tests. Certaines conditions telles que la contamination microbienne des régimes alimentaires de ces modèles pourrait affecter les résultats des expériences. L’alimentation des animaux de laboratoire est l’une des voies de contamination les plus importantes. Cette étude visait à montrer l’effet de l’irradiation gamma sur la réduction des concentrations de bactéries, teneur en éléments nutritifs et concentrations de certains minéraux et oligo-éléments dans les régimes alimentaires des animaux de laboratoire. Des granulés de grande et petite taille d’un diamètre respectif de 10–15 mm (couramment utilisés chez le rat et le hamster) et des de 3–5 mm (utilisés pour les lapins et les cobayes) contenant du lait en poudre écrémé (lait écrémé en poudre) comme additif alimentaire, ont été exposés à une irradiation gamma à des doses allant de 3 à 30 kGy. La contamination microbienne totale et tout changement éventuel de la composition de certains éléments minéraux nutritifs et la teneur en éléments nutritifs bruts a été déterminée avant et après irradiation. Nos données ont révélé que 25 kGy en granulés et 18 kGy dans SKM ont eu des effets supérieurs dans la réduction de la contamination bactérienne avec peu de changement de la teneur en éléments nutritifs bruts, des minéraux et des oligo-éléments constituant les besoins en éléments nutritifs des animaux de laboratoire. Selon nos résultats, l’irradiation gamma a eu des effets minimes sur le contenu en nutriments bruts et sur la concentration de certains minéraux et oligo-éléments des aliments et a permis d‘éliminer la charge de contamination bactérienne et fongique. En utilisant l'irradiation gamma, cette méthode pourrait aboutir à un résultat favorable dans le contrôle de la contamination microbienne des régimes alimentaires des animaux.

Keywords [French]

  • Irradiation gamma
  • Animal de laboratoire
  • Régime alimentaire
  • Bactéries
  • Granulés

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Archives of Razi Institute
Volume 74, Issue 2
June 2019
Pages 175-182

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