ORIGINAL_ARTICLE Prenatal gross morphologic, morphometric and histologic developmental features of the dromedary spleen were studied. The dromedary gestation period (13 months) was categorized into four (1-4) phases and ten developing spleens per growth phase were sampled. Splenic topographical anatomy was noted before being eviscerated from each foetus. Morphologic and morphometric features of the eviscerated spleens were immediately documented and 2 – 4 mm thick samples were collected for histological analysis. The developing spleen was dark brown in colour, semilunar shaped and significantly increased (p > 0.05) in size and weight across the four phases of prenatal development. The full-term dromedary spleen was observed tohave unique histological features. Its capsule had an inner smooth muscle and an outer predominant connective tissue layer.The pumping of stored blood from the muscular capsule and trabeculae was proportionate to the body’s requirement. Thesplenic venous return was characterized by blood flow from the red pulp (venous sinusoids) to the peritrabecular sinuses, subcapsular sinuses and finally to the splenic veins. The dromedary has a sinusal type of spleen and has both open and closed types of circulation. The presence of closed circulation and absence of marginal sinus could be the reason for dromedary main health problems of blood parasites; Trypanosoma evansi. It was concluded that most of the salient features of the postnatal spleen were already evident in the first growth phase and became developed by the second phase. Other growth phases were mainly characterized by increase in sizes. https://macvetrev.mk/Files/Article/2019/10.2478/macvetrev-2019-0018/macvetrev-2019-0018.pdf 2020-10-15T09:00:00 141 149 10.2478/macvetrev-2019-0018 development dromedary foetus histology morphology spleen Alhaji Zubair Jaji false 1 Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Ilorin, P.M.B., 1515, Ilorin, Kwara State, Nigeria AUTHOR Adamu Saleh Saidu adamudvm13@gmail.com false 2 Department of Veterinary Public Health and Preventive Medicine, University of Maiduguri, P.M.B., 1069, Maiduguri, Borno State, Nigeria LEAD_AUTHOR Mohammed Bakari Mahre false 3 Department of Veterinary Physiology and Biochemistry, Faculty of Veterinary Medicine, University of Maiduguri, P.M.B., 1069, Maiduguri, Borno State, Nigeria AUTHOR Mbaya Pindar Yawulda false 4 Department of Veterinary Public Health and Preventive Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria AUTHOR Ibrahim Alhaji Girgiri false 5 Department of Veterinary Anatomy, Faculty of Veterinary Medicine, University of Maiduguri, P.M.B., 1069, Maiduguri, Borno State, Nigeria AUTHOR Piyush Tomar false 6 Department of Veterinary Public Health and Epidemiology, College of Veterinary Sciences, LUVAS, Hisar-125004, Haryana, India AUTHOR Faruk Da'u false 7 Department of Veterinary Services, Ministry of Agriculture and Natural Resources, Kano, Kano State, Nigeria AUTHOR Alshamarry, H.A. 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