R. Mihaylov, R. Dimitrov, V. Yordanova
Abstract. The main goal of the study was to be determined some age linked ultrastructure features of the duodenum in specific bird species. The investigated are 20 birds from each – Japanese and Wild quails. They were divided into four age groups (1-st, 20-th, 45-th и 60-th day of hatching; 5 birds in each age group). The materials for the electon microscopic study were obtained from the middle section of the duodenum. Onto the apical surface of the enterocytes of the duodenum with the one day old Japanese and Wild quails were determined evenly located and with similar height microvillies. They covered the apical surface of the enterocites and arround the apical parts was seen glycocalyx. The height of the duodenal microvilli of the twenty days old Japanese quails was greater from those of the one day old. The 45 days old and 60 days old quails the microvilli, covering the apical surface of the enterocytes were evenly placed, but their height was continuously growing. The height of the duodenal microvilli of the one day old Japanese and Wild quails was equal. With the 20, 45 and 60 days old quails, the height of the microvilli of the Wild type were higher from the microvillies of the Japanese quails. We beleive the difference of the microvillies height of the duodenum with the Wild and the Japanese quail is due to the distingtion in the nutritive habits and requirements of the investigated birds. The Wild quail is a bird, which is in a need of greater reabsorbtion mucosa of the small bowel and most likely is the reason the duodenal microvilli to be higher compare to the Japanese one.