Chilean brush tailed mouse (): a diurnal precocial rodent as a new model to study visual receptive field properties of superior colliculus neurons.

Lab rodent species commonly used to study the visual system and its development (hamsters, rats, and mice) are crepuscular/nocturnal, altricial, and possess simpler visual systems than carnivores and primates. To widen the spectra of studied species, here we introduce an alternative model, the Chilean degu (). This diurnal, precocial Caviomorph rodent has a cone enriched, well-structured retina, and well-developed central visual projections.

Cognitively impaired aged Octodon degus recapitulate major neuropathological features of sporadic Alzheimer's disease.

The long-lived Chilean rodent (Octodon degus) has been reported to show spontaneous age-dependent neuropathology and cognitive impairments similar to those observed in human AD. However, the handful of published papers on degus of differing genetic backgrounds yield inconsistent findings about sporadic AD-like pathological features, with notably differing results between lab in-bred degus versus outbred degus. This motivates more extensive characterization of spontaneously occurring AD-like pathology and behavior in degus.

Can social behaviour drive accessory olfactory bulb asymmetries? Sister species of caviomorph rodents as a case in point.

In mammals, the accessory olfactory or vomeronasal system exhibits a wide variety of anatomical arrangements. In caviomorph rodents, the accessory olfactory bulb (AOB) exhibits a dichotomic conformation, in which two subdomains, the anterior (aAOB) and the posterior (pAOB), can be readily distinguished. Interestingly, different species of this group exhibit bias of different sign between the AOB subdomains (aAOB larger than pAOB or vice versa).

Anatomical Specializations Related to Foraging in the Visual System of a Nocturnal Insectivorous Bird, the Band-Winged Nightjar (Aves: Caprimulgiformes).

Nocturnal animals that rely on their visual system for foraging, mating, and navigation usually exhibit specific traits associated with living in scotopic conditions. Most nocturnal birds have several visual specializations, such as enlarged eyes and an increased orbital convergence. However, the actual role of binocular vision in nocturnal foraging is still debated.

Effects of Habitat and Social Complexity on Brain Size, Brain Asymmetry and Dentate Gyrus Morphology in Two Octodontid Rodents.

Navigational and social challenges due to habitat conditions and sociality are known to influence dentate gyrus (DG) morphology, yet the relative importance of these factors remains unclear. Thus, we studied three natural populations of O. lunatus (Los Molles) and Octodon degus (El Salitre and Rinconada), two caviomorph species that differ in the extent of sociality and with contrasting vegetation cover of habitat used.

Deterioration of the Gαo vomeronasal pathway in sexually dimorphic mammals.

In mammals, social and sexual behaviours are largely mediated by the vomeronasal system (VNS). The accessory olfactory bulb (AOB) is the first synaptic locus of the VNS and ranges from very large in Caviomorph rodents, small in carnivores and ungulates, to its complete absence in apes, elephants, most bats and aquatic species. Two pathways have been described in the VNS of mammals.