Background: Computed tomography currently has a prominent role in diagnosis and evaluation of vertebral column. On the other hand, a thorough knowledge about vertebral column property in normal state is prerequisite an accurate diagnosis of different abnormalities in this region.Objective: The purpose of this study was to present a complete and exact descriptive and morphometric evaluation of thoracic vertebrae in rabbits with computed tomography. In images which were constructed by CT, several structures and different parts of the thoracic vertebrae have been named.Methods: Ten healthy, mature, White New Zealand rabbits were evaluated. The morphologic and morphometric parameters of the thoracic vertebrae were studied. In this study, several parameters of thoracic vertebrae, such as vertebral body height, spinous process height, transverse process length, transverse process width, etc., were measured by computed tomography.Results: Some parameters, such as spinal canal height, spinal canal width, pedicle length, pedicle width, end plate width, and endplate height, had no significant difference through thoracic vertebrae but other parameters, such as vertebral body height, transverse process length, transverse process width, spinous process angle, transverse process angle, and vertebral body length, had a significant difference.Conclusions: In this study, a comprehensive anatomic atlas of CT anatomy of the thoracic vertebrae was produced for use by veterinary radiologists, clinicians, and surgeons. Finally, we must mention these two important points: (1) Many of the differences observed between rabbits and humans are based on the way the trunks of these two creatures are located on the ground and the differences in the way their bodies move. (2) In studies that are done by modelling humans on animals, it should be noted that the terms used in animal anatomy are different and the names are used using the principles of veterinary anatomy.

Background: In mynahs with foreign body ingestion, delayed diagnosis increases the risk of poor outcomes.Objective: The aim of this study was to evaluate various radiologic features on plain and contrast radiographs in mynahs for assessing the presence of ingested foreign bodies.Methods: In our cross‐sectional study, a total of 41 mynahs were included. The diagnosis was made by history, surgery, excision by forceps or excretion in the faeces. Overall, 21 mynahs were considered not to have a foreign body in their gastrointestinal tract. Plain and post‐contrast [oral administration of barium sulphate colloidal suspension of 25% weight/volume (20 mg/kg)] lateral and ventrodorsal radiographs from the cervical and coelomic cavity were taken. Different parameters including oesophageal, proventricular, and small intestinal diameters and opacities were assessed. Image evaluation was performed by two national board‐certified radiologists blinded to the final diagnoses.Results: The inter‐ and intra‐observer reliabilities of the diagnostic features were significant (p < 0.001). The diagnosis of the foreign body was highly accurate [90.2% (95% CI: 76.9%, 92.3%)] with the sensitivity, specificity, and area under the representative characteristic curve of 90.0%, 90.5%, and 0.93%, respectively for plain radiographs. The size and opacity of the oesophagus, proventriculus, and intestinal loops as well as serosal details were significantly different between mynahs with and without foreign body intake (p < 0.05).Conclusions: Lateral and ventrodorsal plain radiographs are highly reliable for diagnosing the presence of non‐opaque obstructing objects in the gastrointestinal tract of mynahs. Attention should be paid to the size and opacity of the oesophagus, extension, and opacity of the proventriculus, segmental opacity of intestinal loops, and decrease in serosal details.

Background: Considering the relationship between human morphology and physiology with the Rhesus monkey, this animal is the most prominent species of laboratory primate for human and animal health research. Moreover, sending Macaca mulatta monkey into space and simulating a living environment for humans shows the similarity of this animal's physiology with humans.Objective: So far, no comprehensive study has been done on computed tomography (CT) scan and radiography of skulls in Rhesus monkeys. Therefore, providing accurate documents from the CT anatomy of the skull in these animals can help us to better understand normal conditions and diseases, and we can use a functional atlas of diagnostic imaging from the skull of this animal.Methods: Ten mature monkeys weighing 6.5 kg were used for this project (five males and five females). A radiographic examination with standard views was performed during general anaesthesia. Then the monkeys were placed in a spherical CT scan during general anaesthesia with standard sternal recumbency.Results: The frontal bone was seen as two parallel radiopaque lines coming forward and downward. The frontal sinus in the Rhesus monkey was not visible in both lateral and dorsoventral radiographs, which could indicate the degeneration of this sinus in this species. The number of teeth in an adult monkey was 32. Molar teeth had a bilophodont arrangement.Conclusions: The comparison between the size of the eye ball in human and Rhesus monkey, unlike other measured parameters, did not differ much, and this indicates that the volume ratio of the eye ball to the whole skull in Rhesus monkey is higher than that of humans.

Background: The Greek or Mediterranean tortoise (Testudo graeca), commonly known as the spur‐thighed tortoise, is a species of tortoise in the family Testudinidae that is found in North Africa, Western Asia and Europe. Several species of this genus are under threat in the wild, mainly from habitat destruction therefore, accurate information about the sexual cycle and the exact time of follicular development can be effective in successful reproduction planning and preventing species extinction.Objective: The experimental part of this study is focused on the evaluation of the reproductive apparatus of tortoises and development of follicles in ovaries during 1 year by ultrasonography and computed tomography.Methods: Ultrasonography and CT scanning was carried out on 10 female ‘T. Graeca’ tortoises which were maintained at Tehran Eram Zoo from November 2021 to November 2022 (1 year). Ultrasonography and CT exams were performed on all animals.Results: In the first study, on 28 November 2021, the ovarian cycle was characterized by the presence of previtellogenic follicles and atretic follicles. The numbers of follicles were best demonstrated on CT examination. Ultrasonography and CT scan in the second study showed no change in type of follicles from previous study. In the third study, atretic follicles were more than previtellogenic follicles, whereas in the fourth one, the numbers of previtellogenic follicles were more than atretic follicles. In following, at 6 and 29 June 2022, the absence of atretic follicles and just presence of previtellogenic follicles were observed. On 20 July 2022, the presence of a few number of atretic follicles and more previtellogenic follicles were noticed. On 30 July 2022, the absence of atretic follicles and presence of previtellogenic follicles and, for the first time, preovulatory follicles were obvious. In four following studies the absence of atretic follicles and the presence of previtellogenic follicles were diagnosed. In the last study, the absence of atretic follicles and the presence of preovulatory and previtellogenic follicles were observed.Conclusion: In current study, the reproductive cycle of female T. Graeca is evaluated during 1 year in captivity with ultrasonography and CT scan. It can be concluded that in captivity, the reproductive cycle does not result in the formation of eggs or calcareous shells and atretic follicles in the study year continued as before; so this should be highly considered in captivity breeding programmes. This study also revealed that among imaging modalities, CT scan is the best modality for detecting the shape, size, type and numbers of the follicles for further evaluation of location and shape of the follicles.

Background: The thymus is the first lymphoid organ formed to regulate a newborn’s immunity. It reaches its maximum size during puberty, after which it undergoes an atrophic procedure called involution, but its ability to grow again in response to some stresses, such as infections, neoplasia, surgeries, chemotherapy, and radiotherapy is maintained. There is no comprehensive study on computed tomographic features of thymus in dogs. So, the goal of the present study is to gain better insight into the thymus using computed tomography as a non-invasive method. Methods: One hundred and fifty dogs classified in five age groups and five breed groups were recruited to this study and the thymus was evaluated using a 2-slice computed tomography machine. The inclusion criteria for the present study were having a normal complete blood count, plain and post-contrast CT scan examination of the thoracic region and no history of neoplasia, chemotherapy or radiotherapy. The visibility, density, enhancement, grade, size, volume, shape, borders and lateralization of the thymus were evaluated and statistical analysis was performed. The effect of obesity on thymic grade and volume was also investigated. Results: The visibility, density, dorsal length, volume and grade decreased with increasing age. The thymic shape and lateralization were mostly wedge shaped and left sided, respectively. The borders became concave with aging and increasing body fat content caused an increase in the fatty degeneration of the thymus. Conclusions: Declining thymic density, grade, size and volume with aging are related to thymic involution and fatty degeneration was accelerated by increasing body fat content. Females and males were different only in thymic shape and small and large breeds were different only in thymic volume. The thymus was visible in some geriatric dogs with no underlying disease. We expect that the present work can be used by radiologists in reading thoracic computed tomography but investigation of thymic characteristics in dogs with neoplasia and history of chemotherapy, radiotherapy and thoracic surgeries can complete this study.