Abstract:
Today, cardiovascular diseases are the dominant diseases of animals, which most
often lead to their death both in Ukraine and worldwide. Therefore, morphological studies
of the heart at the cellular, tissue, and organ levels are essential in clinical cardiology for in
vivo ultrasound diagnosis of functional and organic heart lesions. The aim of the study was to
perform a histological and cytomorphometric assessment of the morphological structures of the
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Horalskyi et al.
Ukrainian Journal of Veterinary Sciences. 2023. Vol. 14, No. 4
sheep heart using macroscopic, histological, and morphometric methods. Using morphological
methods, the hearts of sexually mature clinically healthy animals (n=5) belonging to the class
Mammalia – Mammals, species Ovis aries L., 1758 – domestic sheep (ram) were studied. The
absolute and relative heart weights of mature sheep were determined, which are, respectively,
208.4±9.82 g and 0.44±0.007%, and the weight without epicardial fat is 175.0±8.17 g. The heart
of sheep, according to the development index (145.5±4.02%), belongs to the expanded-shortened
anatomical type. The most developed components are the ventricles. At the same time, the ratio
of the mass of the heart ventricles to its net mass is 1:0.78, respectively, the ratio of the mass
of the atria is 1:0.22, and the ratio of the mass of the atrial myocardium to the mass of the
ventricular myocardium is 1:0.29. The largest volume was found in the cardiomyocytes of the left
ventricle – 3982.99±423.96 μm3
, the smaller – in the right ventricle – 2463.02±318.04 μm3
and
the smallest – in the atrial cardiomyocytes – 1215.93±176.94 μm3
. The volumes of cardiomyocyte
nuclei in the left (53.42±5.18 μm3
), right (52.85±4.33 μm3
) ventricles and atria (50.16±4.57 μm3
)
were almost identical. Nuclear-cytoplasmic ratio was the lowest in cardiomyocytes of the left
ventricle – 0.0136±0.0062, slightly higher in cardiomyocytes of the right ventricle – 0.0219±0.0079
and the highest – 0.0430±0.0096 in atrial cardiomyocytes. The obtained results on the macroand microscopic structure of the heart of bighorn sheep (Ovis aries L., 1758) complement the
information on the morphology of the sheep heart in the relevant sections of histology and
comparative anatomy and are necessary for clinical cardiology
