Advances in organoid technology for veterinary disease modeling

Organoids are in vitro organ-like structures that faithfully recapitulate many characteristics of a specific organ. During the past decades, major progress has been accomplished in establishing three-dimensional (3D) culture systems toward stem cell-derived organoids. As a significant technological breakthrough, these amazing 3D organoid constructs bridge the conventional 2D in vitro models and in vivo animal models and provide an unprecedented opportunity to investigate the complexities of veterinary diseases ranging from their pathogenesis to the prevention, therapy, or even future organ replacement strategies. In this review, we briefly discuss several definitions used in organoid research and highlight the currently known achievements in modeling veterinary diseases, including infectious and inflammatory diseases, cancers, and metabolic diseases. The applications of organoid technology in veterinary disease modeling are still in their infancy stage but the future is promising.

Diagnostic pathology in microbial diseases of sheep or goats

Post-mortem examination is a key step in the diagnostic process of infectious diseases in sheep and goats. Diagnostic pathology deals with identification and study of lesions, at the same time providing also significant clues regarding pathogenesis of the diseases. This article reviews the salient pathological findings associated with the most significant infectious diseases of sheep and goats present in countries where small ruminants are a relevant agricultural industry. Lesions are reviewed according to the different organ systems where they occur. Emphasis has been given in the description of the salient lesional patterns than can be identified in each organ and which can be of help in the differential diagnosis of the lesions caused by bacteria, viruses, fungi or prions. Finally, a review of the usefulness of ancillary tests that may be used on various tissue samples for performing an aetiological diagnosis, is included; the application of various techniques, from immunohistochemistry to molecular biology-based tests, is described.