BACKGROUND: Ambient temperature has a significant effect on the thyroid gland function. Thyroid gland can be assessed by ultrasonography and measurement of thyroid hormones. OBJECTIVES: The aim of this survey was normal ultrasonographic findings of thyroid gland in cat in warm (July) and cold (February) seasons. METHODS: The study was conducted on 30 native, adult healthy cats. Thyroid hormones including T3 and T4 were measured in each cat before ultrasonography. After finding thyroid gland, echogenesity, length, width and height of each lobe (right and left) were measured. RESULTS: Both thyroid lobes were scanable and symmetrical on each side. In sagittal plane it had a fusiform shape and in transverse plane it appeared as an oval or roughly triangular structure. The thyroid parenchyma was homogenously echogenic. The echogenecity of the gland was more than the neck muscles and no difference was seen between cold and warm seasons. Dimensions of each lobe were slightly larger in cold season than warm season. The differences in width and volume were significant (p<0.05) but the differences were not significant in length and height (p>0.05). The mean of the length, width, height and volume of both lobes were in normal range for cat with the same weight. Total means of length, width, height (mm) and volume (cm3) of both lobes were 17.2, 2.6, 2.7, and 0.07 in two seasons respectively. Also, the difference was significant in concentration of T3 and T4 hormones between cold and warm seasons, so that thyroid hormone concentrations were higher in cold season than warm season (p<0.05). CONCLUSIONS: It seems that the reduction in air temperature has an extraordinary effect on increasing thyroid gland size and thyroid hormone concentrations in native adult cats in Ahvaz district. This effect can be due to the influence of cold in the increase of body metabolism and thyroid gland function.

BACKGROUND: Reproductive diseases are among the most important life threatening problems in captive female iguanas. Egg binding is a reproductive disorder in which female iguana cannot lay one or more of its eggs, mainly caused by improper husbandry. Physiological and pathological process of egg production such as egg binding in iguanas has to be assessed more. Objectives: In this study, diagnostic value of two modalities, radiography and ultrasonography, have been compared for evaluation of egg binding in green iguana. Methods: In this study ultrasonography and digital radiography were used as non-invasive methods to evaluate and describe dystocia in captive female green iguanas. Ultrasonography was performed in ventral aspect of abdomen in two sagittal and transverse planes. While radiographic images were taken in both dorso-ventral (DV) and lateral projections. Results: Ultrasonography provided more accurate and informative results than digital radiology. Radiography can be used to detect gravidity and presence of large eggs or follicles. Heterogeneous echogenic eggs or follicles, with different egg size, irregularity in egg borders and echogenic free fluid in celomic cavity were detected in egg-bound green iguanas. Among these ultrasongraphic evidences, the strongest sign was presence of echogenic free fluid in celomic cavity. However digital radiography is unable to delineate fluids in celomic cavity following egg binding in green female iguanas. Among two radiographic positioning, dorso-ventral view provides more information than lateral images. Conclusions: In conclusion, when we encounter a female green iguana with clinical signs of egg binding, ultrasonography has more advantages than radiography, however both modalities can be informative