Generally the green coloured stool is due to bile secreted by the gall blader. As the food passes throgh the intestines, the color of the stool changes to yellowish due to certain enzymatic activities. the green colour stool indicates the increase in transit time ( time tken by the the food to pass through the intestine). it increases in conditions such as bacterial diarrhoea
, irritable bowel disease, ulcerative colitis
and many more.. here as you are giving history of travelling, you should do your stool examination , it will guide us for further mode of managment.and if ther is frequent latrenes, you should maintain the electrolytes level simply by having salt water.. take care.