European Union Legislation for the Welfare of Animals Used for Scientific Purposes: Areas Identified for Further Discussion.

The Directive 2010/63/EU of the European Parliament and of the Council has been in force for more than a decade and has brought about significant improvements and novel requirements for the welfare of animals used for scientific purposes, while safeguarding research integrity. The Directive sets clear provisions for its scope, the authorization procedures, animal welfare bodies, national committees, cost/benefit analysis, severity classification, retrospective assessment, and statistical reporting, among many others. From this perspective, indicative areas in the existing legislative texts and guidance documents, which may influence animal welfare and scientific integrity, have been identified by the authors after years of working in this field. Suggested solutions to address these areas by potential future revisions in the legislation or other actions to benefit animal welfare are discussed, with the aim to clarify and simplify them for all stakeholders involved.

Changes of blood biochemistry in the rabbit animal model in atherosclerosis research; a time- or stress-effect.

BACKGROUND: Rabbits are widely used in biomedical research and especially as animal models in atherosclerosis studies. Blood biochemistry is used to monitor progression of disease, before final evaluation including pathology of arteries and organs. The aim of the present study was to assess the consistency of the biochemical profile of New Zealand White rabbits on standard diet from 3 to 6 months of age, during which they are often used experimentally. METHODS AND RESULTS: Eight conventional male 3-month-old New Zealand White rabbits were used. Blood samples were taken at baseline, 1, 2 and 3 months later. Plasma glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triacylglycerol concentrations, and alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase activities and malondialdehyde were measured. Statistically significant time-related changes were observed in glucose, total cholesterol and triacylglycerol, which were not correlated with aortic lesions at 6 months of age. Similarly, hepatic enzyme activity had significant time-related changes, without a corresponding liver pathology. CONCLUSIONS: Age progression and stress due to single housing may be the underlying reasons for these biochemistry changes. These early changes, indicative of metabolic alterations, should be taken into account even in short-term lipid/atherosclerosis studies, where age and standard diet are not expected to have an effect on the control group of a study.

Differential effect of Pistacia vera extracts on experimental atherosclerosis in the rabbit animal model: an experimental study.

BACKGROUND: Lipid-enriched diets and oxidative stress are risk factors for the development of atherosclerosis. The effects of the methanolic (ME) and cyclohexane (CHE) extracts of the Pistacia vera nut, often included in the Mediterranean diet, were studied in the rabbit model of atherosclerosis. METHODS AND RESULTS: Twenty-four New Zealand White rabbits received atherogenic diet (Control Group), supplemented with ME (Group ME) or CHE (Group CHE) for 3 months. Previously, a GC-MS and a UHPLC LC-DAD-ESI(-)-HRMS/MS method were developed to investigate the extracts' chemical profiles. Blood samples at baseline and monthly determined lipid profile, lipid peroxidation and liver function. The aorta, myocardium and liver were examined histologically at 3 months.Groups ME and CHE had significantly higher HDL- and non-significantly lower LDL-cholesterol median % changes from baseline than the Control Group. Triacylglycerol was significantly higher in Group CHE vs. Control. MDA values were significantly lower in Group ME vs. Control and CHE. ALT and AST were significantly higher in Group CHE vs. Control. gamma-GT was lower in Group ME vs. Control. Aortic intimal thickness was significantly less in Groups ME and CHE vs. Control; Group ME atherosclerotic lesions were significantly less extensive vs. Groups Control and CHE. Only Group CHE had significant liver fatty infiltration. CONCLUSIONS: During short-term administration concomitantly with atherogenic diet, both P. vera extracts were beneficial on HDL-, LDL-cholesterol and aortic intimal thickness. The ME additionally presented an antioxidant effect and significant decrease of aortic surface lesions. These results indicate that P. vera dietary inclusion, in particular its ME, is potentially beneficial in atherosclerosis management.

Mechanical behavior of colonic anastomosis in experimental settings as a measure of wound repair and tissue integrity.

AIM: To determine the mechanical properties of anastomotic colonic tissue in experimental settings and therefore give a measure of wound healing. METHODS: Thirty-six male Wistar rats were used as experimental models of anastomotic tissue integrity. On the 5th post-operative day, the tensile strength was measured by application of an axial force, providing a quantitative measure of anastomotic dehiscence and leakage. RESULTS: Diagrams of the load as a function of the time [P = P (t)] and of the displacement also as a function of time [Delta s = Delta s (t)] were recorded for each test, permitting the design of the load versus the displacement diagram and thus providing significant data about the critical values of anastomotic failure. Quantitative data were obtained concerning the anastomotic strength of both control specimens (healthy rats), as well as specimens from non-healthy rats for comparison. CONCLUSION: This experimental model provides an excellent method of measuring anastomotic strength. Despite the relative small number of specimens used, this method provides an accurate way of measuring wound repair. More experimental measurements need to be performed to correlate emerging tensile strength values to anastomotic failure.