SLC2A5 and obesity due to melanocortin 4 receptor deficiency: As the gastrointestinal system is exposed to all the mycotoxins in contaminated feed, and GLUT-5 expression levels are significantly affected by various diseases and metabolic disorders, such as diabetes, hypertension, obesity, inflammation and carcinogenesis [14,35,49], more morphometrical and functional studies on hexose transporter expression in norm and during diseases are required in the future.