| Title: | Can domestication shape Canidae brain morphology? The accessory olfactory bulb of the red fox as a case in point |
| Author(s): | Ortiz-Leal I; Torres MV; Villamayor PR; Fidalgo LE; Lopez-Beceiro A; Sanchez-Quinteiro P; |
| Address: | "Department of Anatomy, Animal Production and Clinical Veterinary Sciences, Faculty of Veterinary, University of Santiago de Compostela, Lugo, Spain. Department of Anatomy, Animal Production and Clinical Veterinary Sciences, Faculty of Veterinary, University of Santiago de Compostela, Lugo, Spain. Electronic address: pablo.sanchez@usc.es" |
| DOI: | 10.1016/j.aanat.2021.151881 |
| ISSN/ISBN: | 1618-0402 (Electronic) 0940-9602 (Linking) |
| Abstract: | "BACKGROUND: The accessory olfactory bulb (AOB) is the first integrative center of the vomeronasal system (VNS), and the general macroscopic, microscopic, and neurochemical organizational patterns of the AOB differ fundamentally among species. Therefore, the low degree of differentiation observed for the dog AOB is surprising. As the artificial selection pressure exerted on domestic dogs has been suggested to play a key role in the involution of the dog VNS, a wild canid, such as the fox, represents a useful model for studying the hypothetical effects of domestication on the AOB morphology. METHODS: A comprehensive histological, lectin-histochemical, and immunohistochemical study of the fox AOB was performed. Anti-Galphao and anti-Galphai2 antibodies were particularly useful, as they label the transduction cascade of the vomeronasal receptor types 1 (V1R) and 2 (V2R), respectively. Other employed antibodies included those against proteins such as microtubule-associated protein 2 (MAP-2), tubulin, glial fibrillary acidic protein, growth-associated protein 43 (GAP-43), olfactory marker protein (OMP), calbindin, and calretinin. RESULTS: The cytoarchitecture of the fox AOB showed a clear lamination, with neatly differentiated layers; a highly developed glomerular layer, rich in periglomerular cells; and large inner cell and granular layers. The immunolabeling of Galphai2, OMP, and GAP-43 delineated the outer layers, whereas Galphao and MAP-2 immunolabeling defined the inner layers. MAP-2 characterized the somas of AOB principal cells and their dendritic trees. Anti-calbindin and anti-calretinin antibodies discriminated neural subpopulations in both the mitral-plexiform layer and the granular cell layer, and the lectin Ulex europeus agglutinin I (UEA-I) showed selectivity for the AOB and the vomeronasal nerves. CONCLUSION: The fox AOB presents unique characteristics and a higher degree of morphological development compared with the dog AOB. The comparatively complex neural basis for semiochemical information processing in the fox compared with that observed in dogs suggests loss of AOB anatomical complexity during the evolutionary history of dogs and opens a new avenue of research for studying the effects of domestication on brain structures" |
| Keywords: | Animals Dogs Domestication Foxes Neurons *Olfactory Bulb *Vomeronasal Organ Accessory olfactory bulb Canidae Fox G proteins Immunohistochemistry Lectins Uea Vomeronasal system; |
| Notes: | "MedlineOrtiz-Leal, Irene Torres, Mateo V Villamayor, Paula R Fidalgo, Luis Eusebio Lopez-Beceiro, Ana Sanchez-Quinteiro, Pablo eng Germany 2021/12/14 Ann Anat. 2022 Feb; 240:151881. doi: 10.1016/j.aanat.2021.151881. Epub 2021 Dec 9" |
