RESUMO
Critical-size bone defect models are the standard in studies of the osteogenic potential of biomaterials. The present investigation aimed to evaluate the ability of recombinant human erythropoietin (EPO) to induce trabecular bone healing either alone or combined with a xenograft in a rat femoral critical-size defect model. Five-mm bone defects were created in the femoral diaphysis of fifty-six skeletally mature male Wistar albino rats. The animals were divided into six groups: one control group and five experimental groups. The defects in the control group were left empty, whereas an absorbable collagen cone soaked either with saline or erythropoietin (alone or in combination with xenograft) was placed in locally treated groups. The systemic treatment group received EPO subcutaneously. Bone formation was objectively evaluated through radiography, osteodensitometry and histological examination on post-operative days 30 and 90. The results demonstrate that EPO, locally applied on a collagen scaffold, was capable of inducing bone healing, whereas the single systemically administered high EPO dose had only an insignificant effect on bone formation. The combination of EPO with a bone substitute under the form of cancellous granules resulted in more rapid integration between the xenograft and host bone.
RESUMO
Baseline haematological and biochemical blood parameters in healthy wild birds are key to managing wild populations and to saving critically ill individuals. This knowledge is crucial for the care, rehabilitation and the release of birds after treatment in wildlife rescue centres. Plasma levels provide valuable information for the evaluation of the physical condition of animals. The objective of this study was to obtain reference values of some basic biochemical blood parameters of wild common ravens (Corvuscorax). Between 2020 and 2023, we took blood samples from the wild population of common ravens in Bulgaria (n = 36). We determined the values of 18 parameters - alanine transaminase (ALT, U/I), albumin (g/l), alkaline phosphatase (ALP, U/I), amylase (U/I), aspartate transaminase (AST, U/I), calcium (mmol/l), chloride (mmol/l), cholesterol (mmol/l), creatine kinase (CK, U/I), creatinine (µmol/l), blood glucose (mmol/l), lactate dehydrogenase (LDH, U/I), magnesium (mmol/l), phosphorus (mmol/l), total bilirubin (µmol/l), total protein (g/l), triglycerides (TG, mmol/l) and uric acid (µmol/l). We made a comparative analysis including the regions in which the groups were sampled and the time of year. Most of the presented results were comparable to published values of other species from the Corvidae family and some were higher (ALP, amylase, AST, CK, total protein and uric acid levels). Most of these could be explained by the capture- and handling stress. This is the first report in official literary sources presenting some basic biochemical blood parameters of healthy wild common ravens in Bulgaria. The results may be of use to scientists, veterinarians and other researchers in rescue and rehabilitation centres and they can provide the basis for further studies with regards to animal welfare and health assessment of the species.
