The 2- and 3-dimensional (3D) anatomy and the morphometric properties of the paranasal sinuses of the foal have received little or no attention in the literature. The aim of this study was to obtain details of the paranasal sinuses using multiplane CT imaging to create 3D models and to determine morphological and morphometric data for the sinuses using the 3D models. The heads of five female foals were used in this study. The heads were scanned using computed tomography (CT) in the rostrocaudal direction. After the heads had been frozen, anatomical sections were obtained in the scan position. The 3D models of sinuses and the skull were prepared using MIMICS®. These models were used to assess the surface area and volume of the sinuses, the width, height and orientation of the apertures connecting these sinuses and finally the planar relation of the sinuses with the skull. The right and left sides of all anatomical structures, except the sphenoid sinuses, had symmetric organization on CT images and anatomical sections. The total sinus surface area and volume on both sides were 214.4 cm2 and 72.9 ml, respectively. The largest and the smallest sinuses were the frontal sinus (41.5 ml) and the middle conchal sinus (0.2 ml), respectively. It was found that the planes bounding the sinuses passed through easily palpable points on the head. In conclusion, 3D modeling in combination with conventional sectional imaging of the paranasal sinuses of the foal may help anatomists, radiologists, clinicians and veterinary students.

The aim of this study was to determine the origin, course, termination and anastomosing of the coronary arteries in Angora rabbits. Eight adult healthy male Angora rabbits were used. Coloured latex was injected into the ascending aorta. A. coronaria sinistra of the Angora rabbit had larger diameter than a. coronaria dextra. It was divided into r. proximalis atrii sinistri, r. interventricularis paraconalis and r. circumflexus sinister in six Angora rabbits as well as r. septi interventricularis in two. R. septi interventricularis that stem directly from a. coronaria sinistra in two animals and from r. interventricularis paraconalis in six was a principal vessel responsible for the septum interventriculare. R. marginis ventricularis sinistri originating from r. circumflexus sinister was the most prominent artery on the auricular surface of the heart. R. interventricularis subsinuosus was not detected in Angora rabbits examined. A. coronaria dextra, crossing the sulcus coronarius immediately after its origin, ran obliquely in direction of the sulcus interventricularis subsinuosus to supply the right portion of the heart. The ventricular and septal branches of a. coronaria sinistra and a. coronaria dextra ran subepicardially at the beginning then intramyocardially and mostly parallel to the muscle fibres as surrounded by a thin adipose tissue. Their atrial branches were seen continuously to run subepicardially.

This study was carried out to describe the ramifications of the cardiac veins of Angora rabbit. For this purpose, a total of 16 adult healthy Angora rabbits of both sexes, 1.5-2 years of age, were used. The great, middle, right cardiac veins ran in a subepicardial course and opened into the left cranial vena cava, but some tributaries of the right cardiac veins sometimes also joined various portions of the right atrium. The smallest cardiac veins followed subendocardially and terminated in the right chambers of the heart. Based on their origin, course and frequency, it was concluded that the smallest cardiac veins are primarily responsible for the drainage of the interventricular septum. Results from this study are thought to shed light on further heart-related medical studies, and to contribute considerably to the present anatomical knowledge of the cardiac veins in this species.

Although the cervical spinal cord (CSC) of the horse has particular importance in diseases of CNS, there is very little information about its segmental morphometry. The objective of the present study was to determine the morphometric features of the CSC segments in the horse and possible relationships among the morphometric features. The segmented CSC from five mature animals was used. Length, weight, diameter, and volume measurements of the segments were performed macroscopically. Lengths and diameters of segments were measured histologically, and area and volume measurements were performed using stereological methods. The length, weight, and volume of the CSC were 61.6 ± 3.2 cm, 107.2 ± 10.4 g, and 95.5 ± 8.3 cm3, respectively. The length of the segments was increased from C 1 to C 3, while it decreased from C 3 to C 8. The gross section (GS), white matter (WM), grey matter (GM), dorsal horn (DH), and ventral horn (VH) had the largest cross-section areas at C 8. The highest volume was found for the total segment and WM at C 4, GM, DH, and VH at C 7, and the central canal (CC) at C 3. The data obtained not only contribute to the knowledge of the normal anatomy of the CSC but may also provide reference data for veterinary pathologists and clinicians.

The aims of this study were to determine the total volume of the horse kidney and volume fractions of its functional subcomponents (cortex, medulla, renal pelvis) using stereological methods and investigate any possible difference in the functional subcomponents of the right and left kidneys that may arise from differences in shape. The study was carried out on the kidneys of 5 horses of different breed and sex. The weight of the kidneys was measured by a digital scale, and kidney volume was calculated by Archimedes' principle. Total kidney volume and volume fractions of subcomponents of the right and left kidneys were estimated by the Cavalieri's principle. The weights of the right and left kidneys were 550 ± 25 g and 585 ± 23 g, respectively. The volumes of the right and left kidneys estimated using the Cavalieri method were 542 ± 46 ml and 581 ± 29 ml. The relative organ weight of the kidneys was calculated as 1:330. The densities of the right and left kidneys were determined to be 1.01 and 1.00, respectively. The mean volume fractions of the cortex, medulla and renal pelvis were determined as 55.6, 42.7 and 1.7 in both kidneys. No statistically significant difference existed between morphometric data pertaining to the right and left kidneys (P > 0.05). To determine precisely whether differences in shape cause any difference in the functional subcomponents of the right and left kidneys requires further investigation of differences in the number of microscopically functional unit of the kidney such as renal glomeruli and nephrons.