In the present study, volume values of the cervical segments in the spinal cords of adult ducks weighing 3-4 kg were investigated. Volume values of the grey matter and white matter in the cervical segment of the spinal cord of the ducks were examined stereologically. Ten ducks (genus Anas) without regarding the sex of the animals. All animals were perfused using 10% formaldehyde. The animals were kept in 10% formaldehyde for 1 week to ensure fixation. The ducks were then dissected. The cervical segments were uncovered by removing the cervical vertebrae. Tissue samples were obtained from each of the cervical spinal segments, and 5-mu m-thick cross-sections were obtained from these samples. Sampling was performed at a ratio of 1/250 to obtain 12 cross-sections from each cervical segment of the animals. These sections were stained using the hematoxylin and eosin staining technique. Photos were taken under a microscope. Volume values of whole tissue, grey matter, and white matter were calculated for each cervical segment of the spinal cord of the ducks. Cavalieri's principle was employed for the calculation. As a result, the vertebral column was used as a guide to identify the cervical segments of the spinal cord. The cervical segments were also obtained by dissection without using a decalcification process. It was determined that the number of segments was 15. When mean volume values of the whole cervical segment of the spinal cord in the ducks were evaluated, the highest mean volume was determined as 4.224 mm(3) in segment C15. The cervical spinal segment with the lowest value of white matter was C7 (0.915 mm(3)). When the volume values of the grey matter of the cervical segments of the ducks were examined, it was determined that segments C14 and C15 had the highest values, calculated as 0.511 mm(3) and 0.513 mm(3), respectively. It was determined that segments C12, C13, C14, and C15 were involved in the cervical enlargement.