Sixteen dairy cows were studied to assess the status of the natural antioxidant vitamin E and lipid peroxidation in their livers. Cows with liver failure (n = 7) showed clinical signs of a hepatic encephalopathy and had the following values of selected blood indices: AST > 80 U/l and GLDH > 15 U/l in serum, and venous plasma ammonia > 35 mmol/l. The control group (n = 9) consisted of dairy cows which were recovering from surgery (omentopexy) and were free of any health complications. Blood was analysed for α‐tocopherol, aspartate aminotransferase, glutamate dehydrogenase, γ‐glutamyl transferase, total bilirubin, ammonia, cholesterol, albumin, free fatty acids, glucose, and β‐hydroxybutyrate. Alpha‐tocopherol, triglyceride and malondialdehyde were measured in wet liver tissue. The cows with hepatic failure were clearly low in α‐tocopherol and had significantly lower (P < 0.01) plasma α‐tocopherol than the controls. Both liver triglycerides and MDA were higher (P < 0.05) in the cows with fatty livers. It is concluded that the cows with liver failure had an increase in the intensity of hepatic lipoperoxidative processes and a low antioxidative status, which should be taken into consideration in cases where treatment of the disease is proposed.

Abstract:Iron-based substrates with polyethylene glycol coating were prepared as possible materials for biodegradable orthopedic implants. Biodegradable materials that provide mechanical support of the diseased tissue at the time of implanting and then disappear gradually during the healing process are sometimes favored instead of permanent implants. The implant degradation rate should match the time of the tissue regrowth. In this work, the degradation behavior of iron-based foams was studied electrochemically during immersion tests in Hanks' solution. The corrosion rate of the polyethylene glycol-coated samples increased and the corrosion potential shifted to more negative values. This indicates an enhanced degradation rate as compared to the uncoated material, fulfilling the goal of being able to tune the degradation rate. It is the interfacial interaction between the hydrophilic polymer layer and the iron surface that is responsible for the enhanced oxidation rate of iron.

Summary Thirty dairy cows with left abomasal displacement (LAD) and 14 healthy control cows were studied to assess the status of the natural antioxidant vitamin E, lipid peroxidation in the liver (malondialdehyde‐formation) and its relationship to hepatic lipidosis. Blood concentrations of α‐tocopherol, aminotransferase, glutamin dehydrogenase, free fatty acids, β‐hydroxybutyrate and glucose were determined, α‐tocopherol, tryglyceride, glycogen and malondialdehyde (MDA) in wet liver tissue samples were examined. The dietary α‐tocopherol intake and its plasma changes in LDA cows were also investigated. Cows were divided into four groups according to their liver triglyceride contents (< 20; 20–80; > 80 mg/g of fresh tissue; and control groups). The lowest plasma vitamin E and the highest liver vitamin E levels were found in cows with highest hepatic triglyceride content. The highest increase in plasma α‐tocopherol within 5 days was seen in cows with the lowest liver triglyceride (P < 0.01). The liver triglyceride was positively correlated with liver MDA (r = 0.38; P < 0.05) and negatively with plasma α‐tocopherol (r = −0.41; P < 0.01).

MudroÀ P., J. Rehage, H. P. Sallmann, M. Höltershinken, H. Scholz: Stress Response in Dairy Cows Related to Blood Glucose. Acta Vet. Brno 2005, 74: 37-42.The aim of this study was to investigate whether different pre-surgical blood glucose concentrations have any effect on the course of cortisol and metabolic responses to surgical stress in dairy cows. Eighteen Holstein-Friesian dairy cows, admitted for treatment of left abomasal displacement (omentopexy), were used in the study. Abdominal surgery (the stressor) was performed in the standing position 16 -24 h after admission and lasted approximately 60 min. Blood samples were drawn from the jugular vein prior to surgery, immediately after and then 2, 5, 24, and 72 h after surgery. In order to test the effect of the different blood glucose levels on stress responses the experimental animals were allocated to two groups: 1) six hypoglycaemic cows (glucose < 2.4 mmol/l); 2) twelve normoglycaemic cows. Surgery increased blood glucose in both groups (p < 0.001), however, the glucose rise was less distinct in the hypoglycaemic cows. The surgical stress resulted in a significant increase in plasma cortisol concentrations in both groups (p < 0.001), however there was no difference in cortisol responses between the groups. Similarly, surgery enhanced the blood concentrations of free fatty acids (FFA) and L (+)-lactate in both groups (p < 0.001). In contrast, β-hydroxybutyrate concentrations slightly declined after surgery. On the basis of this study there appears not to be any effect of different plasma glucose on the cortisol and metabolite responses in stressed dairy cows. Therefore, it can be concluded that mechanisms regulating peripheral cortisol concentrations, and thus the animal stress response, are more dependent on the intensity of the stressful stimulus than on the energetic status of animal.

The present investigation was undertaken to study the effects of surgical stress on thiobarbituric acid reactive substances (TBARS) and ferric reducing ability of plasma (FRAP) in dairy cows. Ten Holstein-Friesian dairy cows, mean age 5.26 years, admitted for treatment of left abomasal displacement (omentopexy), were used in our study. Blood samples were collected from the jugular vein prior to surgery, immediately and then 15, 30, 60, 90 min, and 2, 5, 10, and 24 h after reposition of abomasum. Surgical stress resulted in a significant increase in plasma cortisol concentrations (P < 0.001) with the highest mean levels 15 min after surgery (32.4 +/- 18.1 microg/l) as well as in serum levels of glucose (P < 0.001) and non-esterified fatty acids (P < 0.001). Similarly, surgery transiently enhanced the plasma levels of TBARS (P < 0.001). The highest TBARS plasma levels (0.91 +/- 0.18 micromol/l) were recognized 60 min after reposition of abomasums. There were no significant differences in FRAP in dairy cows before and after reposition of abomasum. In conclusion, these data indicate that stress reaction caused by surgical correction of left displacement of abomasum can be associated with higher production of TBARS.

The objective of the study was to evaluate the electrophoretic pattern of serum proteins in dairy cows suffering from various infl ammatory diseases, and to study the infl uence of these diseases on the concentrations of protein fractions. Fourty dairy cows with clinical signs of various infl ammatory diseases were used in the study, including cows with post-partum metritis (n=10), mastitis (n=7), and hoof diseases (n=23). The cows were of a black pied Holstein-Friesian breed, Slovak spotted breed and their crossbreeds at the age of 3.5 to 8 years. Fourteen clinically healthy dairy cows were taken as the control group. The cows were blood sampled for the determination of total serum proteins and serum protein fractions. The protein fractions were divided into albumin, α 1 -, α 2 -, β 1 -, β 2 -, and γ-globulins. In cows with post-partum metritis we found signifi cantly lower concentrations of albumin (P<0.001) and signifi cantly higher values of α 1 -globulins (P<0.01) compared with healthy animals. Signifi cantly higher concentrations of β 1 -globulins were observed in cows with mastitis (P<0.001), while the γ-globulin fraction was non-signifi cantly higher. In cows with hoof diseases we recorded signifi cantly lower values of albumin (P<0.001), signifi cantly higher concentrations of α 1 -and β 1 -globulins (P<0.001), and non-signifi cantly higher β 2 -and γ-globulins. Moreover, in the electrophoretic pattern of serum proteins we found β-γ bridging in thirteen cows with hoof diseases. Presented data suggest marked infl uence of infl ammatory diseases on the concentrations of serum protein fractions in dairy cows. However, further investigations are needed to establish the diagnostic utility of serum protein electrophoresis in bovine clinical practice in relation to infl ammatory diseases.

Spermatozoa must possess many attributes to fertilize an egg but few laboratory methods can assess all of these attributes simultaneously and objectively. Most laboratory methods used to assess the quality of semen in veterinary andrology can be inaccurate and time-consuming. Laboratory techniques which evaluate only one sperm attribute, often provide results that have a weak correlation with fertility. Therefore, semen used for artificial insemination should not be assessed based on the results of one method only but rather on the comprehensive results of several laboratory tests. Flow cytometry is a modern method of analysing diJ169fferent types of cells, including sperm cells. It is based on the scattering of light and fluorescence, the outcome of which yields results that are recorded and evaluated by computer technology which makes an objective assessment. Flow cytometry in combination with fluorescence microscopy and fluorescent probes provides a comprehensive, accurate, objective, and rapid analysis of the ejaculate. In a short time frame it allows us to test thousands of sperm for their structure and properties, even with a minimal amount of semen. This method enables the evaluation of several indicators simultaneously in a population of sperm as a whole or for each sperm individually. It informs us about the selected indicators of sperm quality in the sample by examining the membrane integrity, DNA, mitochondria, acrosome, oxidative stress, and other properties. Flow cytometry has become an important method of evaluating the functional and morphological properties of sperm and is used for research in veterinary science as well as for a routine assessment of the semen quality.

Equine hoof canker and bovine digital dermatitis are infectious inflammatory diseases of the hooves with an unknown etiology. However, anaerobic spirochetes of the genus Treponema are considered to be potential etiological agents. The aim of this study was to find a suitable way to isolate DNA and to detect the presence of treponemal DNA in samples of equine hoof canker and bovine digital dermatitis. DNAzol®® Direct and column kits were used to isolate DNA from samples of equine hoof canker and bovine digital dermatitis. The presence of Treponema spp. was detected using PCR and Sanger sequencing. DNAzol®® Direct is suitable for isolating DNA from these types of samples. Treponemal DNA was detected in equine hoof samples as well as in bovine digital dermatitis skin samples. In equine hoof biopsies, the most frequently detected was Treponema pedis (8/13). Treponema brennaborense (2/13) and Treponema denticola (2/13) were also found. In the case of bovine digital dermatitis, Treponema medium ssp. bovis was confirmed in 14 of 36 skin samples. Treponema pedis (9/36), Treponema vincentii (1/36), Treponema phagedenis (1/36), and Treponema brennaborense (1/36) were detected as well. DNAzol®® Direct was more appropriate for isolation of treponemal DNA because the columns isolation method was more equipment and time-consuming. The presence of several Treponema spp. was determined in the samples. In horses, the most commonly detected species was a T. pedis, while in cattle it was T. medium ssp. bovis.