Search

Simple Summary: Brain aging in mammals is characterized by morphological and functional changes in neural cells. This process, although physiological, leads to progressive cerebral tissue volume loss and functional decline, including memory loss motor neuron deficits and behavioral disorders. It is generally accepted that aging is associated with a shift in the proportion between the functional cell (neuron) and support cells (astrocytes) in favor of the latter, which also appear different from those of healthy and young brain tissue. Also, dysfunctional autophagy contributes to altering brain homeostasis. This review summarizes and updates the most recent knowledge about brain aging through a comparative approach, where similarities and differences in some mammalian species are considered. Brain aging in mammals is characterized by morphological and functional changes in neural cells. Macroscopically, this process, leading to progressive cerebral volume loss and functional decline, includes memory and motor neuron deficits, as well as behavioral disorders. Morphologically, brain aging is associated with aged neurons and astrocytes, appearing enlarged and flattened, and expressing enhanced pH-dependent β-galactosidase activity. Multiple mechanisms are considered hallmarks of cellular senescence in vitro, including cell cycle arrest, increased lysosomal activity, telomere shortening, oxidative stress, and DNA damage. The most common markers for senescence identification were identified in (i) proteins implicated in cell cycle arrest, such as p16, p21, and p53, (ii) increased lysosomal mass, and (iii) increased reactive oxygen species (ROS) and senescence-associated secretory phenotype (SASP) expression. Finally, dysfunctional autophagy, a process occurring during aging, contributes to altering brain homeostasis. The brains of mammals can be studied at cellular and subcellular levels to elucidate the mechanisms on the basis of age-related and degenerative disorders. The aim of this review is to summarize and update the most recent knowledge about brain aging through a comparative approach, where similarities and differences in some mammalian species are considered. [ABSTRACT FROM AUTHOR]

Simple Summary: Asinara donkeys are unique worldwide for expressing a particular form of albinism spread to all individuals of the breed. This peculiar condition of oculo-cutaneous albinism of type 1 (OCA1) is a rare condition from a recessive autosomic mutation, fixed through generations, thanks to the isolation of donkeys on Asinara Island (from which the breed name originates) favoring inbreeding. Asinara island is a small island of Sardinia, one of the biggest islands in the Mediterranean sea. Asinara donkeys have shown good adaptation to the Mediterranean climate through various metabolic strategies, one of which relies on endogenous retinol mobilization during the positive photoperiod for protective effect and adequate circulating vitamin E. Indeed, their exposure to sun radiation and high temperature on one hand, and the lack of melanin in the coat, skin, iris and mucocutaneous junctions on the other, require them to overcome such an extended lack of photoprotective pigment (melanin) in alternative ways to prevent UV radiation damage. In this investigation, our interest was oriented toward screening the complete blood cell count to understand whether metabolic adaptation to the environment involved blood cell lines. Such an idea comes from the fact that in humans, a particular condition of albinism is reported to share the same gene with other mutations involving hemoglobin synthesis. In our case, significant differences were observed in relation to red blood cells (RBCs), in terms of their average volume (MCV), width distribution (RDW-CV), and width deviation (RDW-SD), in comparison to pigmented (gray) Sardo donkeys. The complete blood cell count (CBC) was screened in a group of 15 donkeys, of which 8 were of Asinara breed (oculocutaneous albinism type 1, OCA1) and 7 of Sardo breed (gray coat). All donkeys were kept under same management and dietary conditions and underwent periodic health monitoring in the month of June 2024, at the peak of the positive photoperiod, at Mediterranean latitudes. One aliquot of whole blood, drawn from each individual into K2-EDTA containing tubes, was analyzed for the complete blood cell count through an automatic analyzer, within two hours of sampling. Data were analyzed and compared by one-way ANOVA, where the breed was an independent variable. All animals appeared clinically healthy, though mild eosinophilia was observed in Sardo donkeys. The red blood cell line showed peculiar traits for Asinara donkeys, which displayed significantly higher circulating red blood cell numbers than gray coat Sardo donkeys (RBC, 5.19 vs. 3.80 1012/mL ± 0.98 pooled-St. Dev, respectively; p = 0.017). RBCs also exhibited a smaller diameter and higher degree of anisocytosis in Asinara donkeys, along with lower hematocrit value, albeit within physiological ranges. Taken all together, such hematological profile depicts a peculiar trait of the red blood cell line in albino donkeys during the positive photoperiod. [ABSTRACT FROM AUTHOR]

The Sardinian partridge is a monogamous wild bird species of least concern according to IUCN list at present, though formerly accounted among threatened species for decades. The creation of couples is crucial in captivity, because forced pairing in cages can lead to poor welfare of birds, specially of females. This study investigated the impact of single versus couple caging of Sardinian partridges during non‐laying period based on the collection and interpretation of indirect and non‐invasive parameters (feed intake; space availability; excreta quality; and nutrient utilization). A total of 24 couples of breeding partridges were enrolled for two consequent phases of a same investigation (lasting 15 days each). During phase 1, all couples were fed ad libitum with a pelleted complete diet (DM, 905 g kg−1 of diet; CP, 160 g kg−1; and EE, 25 g kg−1). In phase 2, each male from 12 out of 24 couples was moved to an identical cage close to that where the female remained alone, to keep visual contact. The rest of couples continued to be kept like in phase 1. During phases 1 and 2, feed intake and excreta outputs were recorded daily. Pooled excreta of the last 3 days from couples and single birds were assessed for pH and DM, CP and ash content. Nutrient digestibility was calculated. No significant differences were noted between single versus couple caging regarding body weight (438 vs. 422 g respectively) or nutrient digestibility. However, singly housed males reduced daily feed intakes and females increased daily feed intake per g−1 BW (0.041 vs. 0.052 g, respectively, p < 0.001). Our results suggest that singly caged partridges from permanent couples can improve the access to feed and reduce competition during the non‐mating season. [ABSTRACT FROM AUTHOR]