Hyaline articular cartilage has unique physiological, biological, and biomechanical properties with very limited self-healing ability, which makes the process of cartilage regeneration extremely difficult. Therefore, research is currently focused on finding new and potentially better treatment options. The main objective of this in vivo study was to evaluate a novel biocement CX consisting of tetracalcium phosphate–monetit biocement hardened with a phytic acid–phytase mixture for the regeneration of osteochondral defects in sheep. The results were compared with tetracalcium phosphate–monetit biocement with classic fast-setting cement systems and untreated defects. After 6 months, the animals were sacrificed, and the samples were evaluated using macroscopic and histologic methods as well as X-ray, CT, and MR-imaging techniques. In contrast to the formation of fibrous or fibrocartilaginous tissue on the untreated side, treatment with biocements resulted in the formation of tissue with a dominant hyaline cartilage structure, although fine fibres were present (p < 0.001). There were no signs of pathomorphological changes or inflammation. Continuous formation of subchondral bone and hyaline cartilage layers was present even though residual biocement was observed in the trabecular bone. We consider biocement CX to be highly biocompatible and suitable for the treatment of osteochondral defects.

The vertebral arteries, as the first branches from the subclavian arteries, normally enter into the transverse foramen of the sixth cervical vertebra in dogs. This case report presents the non‐standard course of the left vertebral artery and unilateral asymmetry of the sixth cervical vertebra in a 14‐year‐old female mixed breed dog. The anomaly was an incidental finding during the preparation of a corrosion cast prepared for educational and scientific purposes. The left sixth cervical vertebra transverse foramen and the ventral lamina were not developed. The left vertebral artery originated normally from the left subclavian artery, but atypically entered into the transverse foramen of the fifth cervical vertebra. On the right side, the anatomical structures of the sixth cervical vertebra and the course of the right vertebral artery were normally developed. To our knowledge, this is the first case of such an anomaly described in a dog.

Precise knowledge of the species-/breed-specific anatomy is important for accurate diagnosis and treatment. Existing literature has also been increasing in accordance with the growing demands of biomedical research, wherein mammals, including cats, have been used worldwide. Based on a vascular corrosion cast, complete duplication of the caudal vena cava (dCVC) was accidentally found in a 10-year-old male cat. The two separate symmetric veins corresponding to two caudal venae cavae cranially directed on both sides of the aorta; their first tributaries were the duplicated right and left deep circumflex iliac veins, and the median sacral vein ended in the right common iliac vein. At the L4 vertebra level, the left caudal vena cava crossed the aorta ventrally. It united with the right CVC immediately above the renal veins at the level of the cranial mesenteric artery (L2–L3). Embryologic knowledge is essential to understand the differences between the CVC variants in domestic mammals and the inferior vena cava in humans. However, views regarding the post-hepatic segment of the CVC during development vary considerably. Therefore, our case report also includes a summary of the CVC developmental theories and their clinical impact. We believe that this case and literature review contribute to the knowledge regarding the deep abdominal veins’ variability, concomitant pathologies, and accurate diagnosis and surgery. Additionally, the latest robust studies demonstrating the exclusive participation of the caudal cardinal veins in the CVC development are discussed.

Cats are one of the most common companion animals, and they differ from dogs in several important ways. Considering the central importance of anatomy in high-quality medicine, the treatment of the feline mandible, mostly during intraoral procedures requiring general anaesthesia, has many important features. In cats, the major artery of the brain is the maxillary artery that forms unique structure – the rete mirabile. The rete mirabile is a plexus like vascular structure that lies extracranially and communicates with brain arterial circle through the orbital fissure. The development of the brain vasculature is different in cats, and it includes obliteration mechanisms of the internal carotid artery. The course of the maxillary artery that forms the rete mirabile has a strong relationship to the angular process of the mandible. Emphasis should be placed on manipulation with the feline mandible, especially during open-mouth procedures, as mistakes can lead to blindness, deafness, and central neurological disorders due to compression of the maxillary artery by the angular process of the mandible. This paper focuses on the anatomy and function of the blood supply to the brain, which is very specific in domestic cats and other felids.

Calcific aortic valve disease (CAVD) is the most common reason for valve replacement surgery in elderly people. CAVD is a slowly progressive disorder ranging from a mild aortic sclerosis to a more severe aortic stenosis. This article describes a case of heterotopic ossification in the aortic valve accidentally found at necropsy of presumably healthy 21-year-old mare euthanized for reasons unrelated to the cardiovascular system. Histopathological examination confirmed mature lamellar bone in the aortic valve area. To our best knowledge, heterotopic ossification of the aortic valve is a rare condition in horses and it has been reported in only two cases.

The parotid duct has been reported to be the most common site of sialoliths in horses. In this case report, we described the first confirmed case of the equine sialolithiasis in Slovakia. The work was aimed to describe the transcutaneous approach to removing the sialolith, which manifested as a hard painless mass in the area of the maxillary cheek teeth, in a 14-year-old Slovakian warmblood mare. Pathological-anatomical and histological examination after extirpation confirmed the presence of parotid duct ectasia resulting from calculus. The mineral composition of the sialolith was determined with atomic absorption spectroscopy using X-ray powder diffraction. The sialolith was successfully extirpated transcutaneously, without complications or recurrence.