Brain Abscesses in Domestic Ruminants: Clinicopathological and Bacteriological Approaches.

Brain abscesses in ruminants often arise from primary infection foci, leading to an unfavorable prognosis for affected animals. This highlights the need for comprehensive studies on brain abscesses across different ruminant species. We retrospectively investigated medical records of epidemiological, clinical, neuroimaging, anatomopathological, and bacteriological findings in six ruminants (three goats, two cows, and one sheep) diagnosed with brain abscesses. All animals studied were female. Apathy (50%), compulsive walking (33%), decreased facial sensitivity (33%), head pressing (33%), seizures (33%), semicomatous mental status (33%), strabismus (33%), unilateral blindness (33%), and circling (33%) represented the most common neurologic signs. Leukocytosis and neutrophilia were the main findings in the hematological evaluation. Cerebrospinal fluid (CSF) analysis revealed predominant hyperproteinorrachia and pleocytosis. In three cases, computed tomography or magnetic resonance imaging were used, enabling the identification of typical abscess lesions, which were subsequently confirmed during postmortem examination. Microbiological culture of the abscess samples and/or CSF revealed bacterial coinfections in most cases. Advanced imaging examinations, combined with CSF analysis, can aid in diagnosis, although confirmation typically relies on postmortem evaluation and isolation of the causative agent. This study contributes to clinicopathological aspects, neuroimages, and bacteriological diagnosis of brain abscesses in domestic ruminants.

In Vitro Transdifferentiation Potential of Equine Mesenchymal Stem Cells into Schwann-Like Cells.

Schwann cells (SCs) are essential for the regenerative processes of peripheral nerve injuries. However, their use in cell therapy is limited. In this context, several studies have demonstrated the ability of mesenchymal stem cells (MSCs) to transdifferentiate into Schwann-like cells (SLCs) using chemical protocols or co-culture with SCs. Here, we describe for the first time the in vitro transdifferentiation potential of MSCs derived from equine adipose tissue (AT) and equine bone marrow (BM) into SLCs using a practical method. In this study, the facial nerve of a horse was collected, cut into fragments, and incubated in cell culture medium for 48 h. This medium was used to transdifferentiate the MSCs into SLCs. Equine AT-MSCs and BM-MSCs were incubated with the induction medium for 5 days. After this period, the morphology, cell viability, metabolic activity, gene expression of glial markers glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), p75 and S100ß, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and glial cell-derived neurotrophic factor (GDNF), and the protein expression of S100 and GFAP were evaluated in undifferentiated and differentiated cells. The MSCs from the two sources incubated with the induction medium exhibited similar morphology to the SCs and maintained cell viability and metabolic activity. There was a significant increase in the gene expression of BDNF, GDNF, GFAP, MBP, p75, and S100ß in equine AT-MSCs and GDNF, GFAP, MBP, p75, and S100ß in equine BM-MSCs post-differentiation. Immunofluorescence analysis revealed GFAP expression in undifferentiated and differentiated cells, with a significant increase in the integrated pixel density in differentiated cells and S100 was only expressed in differentiated cells from both sources. These findings indicate that equine AT-MSCs and BM-MSCs have great transdifferentiation potential into SLCs using this method, and they represent a promising strategy for cell-based therapy for peripheral nerve regeneration in horses.