Translational models for vascular cognitive impairment: a review including larger species.

BACKGROUND: Disease models are useful for prospective studies of pathology, identification of molecular and cellular mechanisms, pre-clinical testing of interventions, and validation of clinical biomarkers. Here, we review animal models relevant to vascular cognitive impairment (VCI). A synopsis of each model was initially presented by expert practitioners. Synopses were refined by the authors, and subsequently by the scientific committee of a recent conference (International Conference on Vascular Dementia 2015). Only peer-reviewed sources were cited. METHODS: We included models that mimic VCI-related brain lesions (white matter hypoperfusion injury, focal ischaemia, cerebral amyloid angiopathy) or reproduce VCI risk factors (old age, hypertension, hyperhomocysteinemia, high-salt/high-fat diet) or reproduce genetic causes of VCI (CADASIL-causing Notch3 mutations). CONCLUSIONS: We concluded that (1) translational models may reflect a VCI-relevant pathological process, while not fully replicating a human disease spectrum; (2) rodent models of VCI are limited by paucity of white matter; and (3) further translational models, and improved cognitive testing instruments, are required

Dairy cows trade-off feed quality with proximity to a dominant individual in Y-maze choice tests

In this experiment choice tests were used as a tool to determine how dairy cows perceive their feeding environment with specific emphasis on understanding the challenges that low ranking animals face when forced to feed in the presence of socially dominant cows. It was hypothesised that cows would trade-off proximity to a dominant individual at the feed-face with access to food of a high quality. Thirty Holstein Friesian cows were used in the study. A test pen contained a Y-maze, with one black feed bin placed in one arm of the maze and one white feed bin placed in the other arm. During a training phase half of the cows were trained to make an association between the black bill and high quality food (HQF), and the white bin and low quality food (LQF). The other half was trained with the opposite combination, to prevent any colour bias. The status of each cow was assessed and dominant and subordinate cows were paired. Choice test I determined if cows had correctly learned the association between colour (of food bin) and food quality. Cows were presented with one black and one white bin in the two arms of the maze, with the presentation of each coloured bin in the left and right arms randomised. When cows achieved an 80% success rate of HQF preference they proceeded onto the next stage, where two further tests were presented. In choice test 2, the subordinate cow was presented with two bins of HQF, one of which had a dominant cow feeding from it. In test 3. cows had a choice of HQF and LQF, with the dominant cow present at the HQF bin. Cows showed a significant preference for feeding on HQF alone rather than next to a dominant (P &lt; 0.001). When they were &quot;asked&quot; to trade-off feed quality with feeding next to a dominant, the majority chose to feed alone on LQF (P &lt; 0.01). These results suggest that social status within a herd Could significantly affect feeding behaviour, especially in situations of high competition and for subordinate individuals. (C) 2008 Elsevier B.V. All rights reserved.</p

Pathological findings in spontaneously dead and euthanized sows - a descriptive study

Background:A high rate of euthanized and spontaneously dead sows causes production losses and likely indicatesunderlying welfare problems. Identification of predisposing factors to on-farm deaths requires a thoroughunderstanding of the causes. Post-mortem examination is needed for a proper diagnosis. The aims of thisdescriptive study were to determine causes of spontaneous deaths and euthanasia in sows in a conveniencesample of Finnish herds and to describe pathological findings in the locomotor system and in teeth and gums.Results:This study described post-mortem findings in 65 sows found dead or euthanized on 15 farms. All but oneof the sows presented with two or more pathological findings. The majority of primary pathologic-anatomicdiagnoses (PAD-1) were inflammatory. The most prevalent diagnoses were arthritis and peritonitis (9% of sowseach). The locomotor system was the body part most commonly affected by lesions. Findings in the locomotorsystem unassociated with death were present in 85% of the animals, additionally 29% of PAD-1 s concerned thelocomotor system. The prevalence for both degenerative joint disease and tooth wear was 71%. Farmers had notedclinical signs within 30 days of death in every euthanized sow and in half of the spontaneously dead ones. Thefarmer’s impression of the cause of death agreed at least partly with the PAD-1 in 44% of the cases.Conclusion:Multiple pathologies were the norm in the present animals. This may indicate an extended course ofillness and therefore also an unnecessary delay in medical treatment or euthanasia. The prevalence and clinicalrelevance of the most common disorders, including degenerative joint disease and tooth wear, need to beelucidated.Peer reviewe