Abstract

This study investigates the morphological, morphometric characteristics of thoracic and lumbar intervertebral discs (IVD) in guinea pigs. The main objective of this research is to provide baseline data for comparative studies in veterinary and medical fields, especially in relation to common lumbar diseases. In this study, 5 guinea pigs were examined and morphometric parameters were measured using micro-CT images and macroscopic dissection   and compared with each others.

The results showed that 13 thoracic and 6 lumbar discs were identified in guinea pigs. Thoracic discs change from a round shape in the T1-T3 region to triangular and heart-shaped structures in the T4-T13 region, while lumbar discs have a more consistent heart shape. Morphometric analysis revealed statistically significant differences. Lumbar discs were larger than thoracic discs in lateral, dorsal dimensions, and disc area, annulus fibrosus, and nucleus pulposus. In particular, a significant increase in lateral width and disc area was observed at lumbar L5 and L6. Histologically, both disc types had well-organized nucleus pulposus, annulus fibrosus, and endplates. The endplates were composed of hyaline cartilage, fibrocartilage, calcified cartilage, and secondary ossification centers with large vascular channels.

Finally, this study demonstrates that although thoracic and lumbar intervertebral discs in guinea pigs retain key features histologically, their distinct morphological and morphometric features reflect adaptation to biomechanical demands. However, due to fundamental differences between humans and guinea pigs, the use of this species as a research model for human intervertebral discs should be done with caution..

Keywords: Guinea pig, Intervertebral disc, pine, roRdent, Micro-CT

abstract Dislocation of the patella is one of the main causes of lameness in dogs and is one of the most common reasons that send pets to the operating room. In this condition, the patella bone is out of its normal position and the movement of the animal is difficult. Although this condition also occurs in cats, most of the reports are seen in dogs, especially small breed dogs. Dislocation of the patella bone, if it worsens, prevents the normal activity of dogs and creates a big problem for them and their owners. Its abundance statistics have been studied by various researchers. However, despite the growing trend of keeping dogs in the last few years, no information regarding the investigation of this condition in Kermanshah city was found during the search in the available scientific source