CT anatomy of the lungs, bronchi and trachea in the Mature Guinea pig (cavia porcellus).

BACKGROUND: Since there is no complete study of topographic features of thorax structures in guinea pigs, this study strives to define the exact topographic features of thorax structures. OBJECTIVES: The aim of this study is to provide comprehensive topographic information about the location of the trachea, bronchi, lungs and heart inside the thoracic cavity in guinea pig, as well as to study the features of these structures, their proximity to other organs and comparative anatomical studies with CT scan images in living samples. METHODS: Ten adult male and healthy guinea pigs were selected. CT scan transverse images were taken. The morphometric parameters of the lungs, bronchi, trachea, heart, thoracic cavity and abdominal cavity were measured. RESULTS: In these studies, the position of organs such as the trachea, lungs and heart were monitored, and specified descriptions of CT scan images and anatomical observations were obtained. We realised that the heart in this animal was not inclined to the left, and due to the equal size of the lungs, the heart was almost on the midline. According to the measurements, 20.05% of the ventral cavity volume was thoracic cavity and 79.95% was abdominal cavity. CONCLUSIONS: According to studies on guinea pigs, the right and left have the volume, and the heart is located between them on the midline without a tendency to the left. It seems that one of the reasons for the reluctance of the heart to the left and its placement on the midline in the guinea pig is that the volume of the two lungs is equal. In the case of guinea pigs, both numerical parameters are smaller than rabbits', but close to it. One of the most important factors in this study is that none of the animals were euthanised, and all of samples were alive after our study.

CT anatomy of cervical vertebrae of Asian elephant (Elephas maximus).

BACKGROUND: Elephants are currently the largest mammals on earth. A comprehensive examination of the anatomy of this animal to diagnose various disorders is required. In addition, due to the heavy head of these animals, adaptations have been made in the anatomical structure of the neck that is worth studying. OBJECTIVE: This study aimed to investigate a standard morphologic and morphometric description of the elephant cervical spine. Another aim of this study was to compare the changes in the cervical skeleton of elephants with horses and cattle. METHODS: For this study, the cervical vertebrae of the Asian elephant, cattle and horse were examined. CT Images were obtained using Somatom Spirit II CT Machine. Statistical analysis was done by SPSS 24 software. RESULTS: Two dorsal tubercles and a groove between them were observed on the dorsal arch of the atlas vertebra of the Asian elephant. In elephant samples, the variation of vertebral body height, spinous process height, transverse process width, vertebral body length and vertebral foramen volume indices were statistically significant. The volume of the vertebral foramen in the elephant decreases in the second vertebra compared to the first vertebra, decreases in the third vertebra, decreases in the fourth, increases in the fifth, decreases in the sixth and increases in the seventh. CONCLUSIONS: In this study, the structure of the cervical vertebrae of the Asian elephant was examined, and certain features were observed. One of the main features was the reduction of the length of the vertebrae, which leads to the decrease of the ratio of neck length to the size of the body. This condition can be due to the high weight of the head in the elephant. To maintain this weight, it is necessary to reduce the length of the neck and confer less mobility.