Canine brachycephalic obstructive airway syndrome (BOAS) is a conformation-related respiratory disorder of dog breeds having congenitally flattened facial and skull anatomy. The aim of the study was to determine oxidative stress parameters, the lipid peroxidation product malondialdehyde, and antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase in BOAS patients before and after surgical treatment and in healthy brachycephalic dogs. Nine healthy brachycephalic dogs that had not undergone surgery and 39 BOAS patients were included in the study. The BOAS patients were classified as grade 1 (5/34), grade 2 (16/34), and grade 3 (13/34) based on the decrease in the radius of the airway in the larynx. In BOAS patients, oxidative stress parameters were determined before and two weeks after surgery, while in control dogs, blood samples were collected only on inclusion to the study. All BOAS patients showed various degrees of improvement in clinical signs after surgery. Significantly lower (P < 0.05) SOD activity was found in grade 2 and 3 BOAS patients than in grade 1 patients. Two weeks after surgery, a significant (P < 0.05) increase in SOD activity in grade 2 and 3 patients was observed. Antioxidant enzyme SOD may play an important role in BOAS and can be used as a biomarker of antioxidant status assessment in BOAS patients.

The aim of the study was to demonstrate a link between uncomplicated Babesia canis infection in dogs and blood concentrations of zinc and copper and erythrocytic antioxidant defence – activities of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The study was based on 15 naturally occurring cases of canine babesiosis with anorexia, pyrexia, depression, pale mucous membrane, splenomegaly and dark red urine. Microscopic examination of Giemsa-stained peripheral blood smears and the results of PCR confirmed B. canis infection. Seven apparently healthy dogs brought in for either a check-up or vaccination were used for comparison. The levels of the erythrocytic antioxidant enzymes - SOD and CAT - were significantly higher in the infected dogs than in cytologically negative dogs. The levels of blood micronutrients were significantly lower in the infected dogs (0.478 μg of zinc per mL vs 1.241 μg/mL and 0.722 μg of copper per mL vs 1.392 μg/mL). Oxidative stress can be posited as one of the mechanisms leading to anaemia in dogs with babesiosis, and therefore antioxidant biomarker and copper and zinc concentrations could be used as indicators of disease severity and prognostic markers.

The study measured the hormonal and protein markers of acute stress, those of oxidative stress and total antioxidant capacity (TAC) in swine oral fluid, determined which of these parameters would be the most appropriate for future livestock welfare assessment and established the time when the samples should be taken. Stress was induced in 7 out of 14 castrated six-week-old Danbred×Duroc pigs by immobilisation on a nasal snare at 8 a.m., 1 p.m., and 6 p.m. and samples were taken both directly after the stressor was applied and 30 min later. The remaining pigs were the control group, which were not immobilised; their samples were taken at the same times. The concentrations of hormones and malondialdehyde (MDA) were measured using liquid chromatography with tandem mass spectrometry, while those of alpha-amylase and TAC were measured using spectrophotometry. The levels of cortisol and cortisone increased with statistical significance immediately after the acute stress response and 30 min later. A cut-off value set at 0.25 ng/mL cortisol concentration was capable of distinguishing between the stressed and control groups with 100% accuracy in evening samples and 95% accuracy overall. Prednisolone was not present, and the levels of testosterone and corticosterone were low and not distinctive. Alpha-amylase became significantly more concentrated during stress induction and 30 min later. The TAC and MDA levels rose after the stress but without statistical significance. The most suitable markers of acute stress were cortisol, cortisone and alpha-amylase. Oral fluid is a reliable material for monitoring the level of pigs’ stress and should be collected in the evening.

The aim of this study was to determine changes of reactive oxygen species (ROS), serum antioxidant capacity (SAC), oxidative stress index (OSi), and α-tocopherol (α-T) during the periparturient period in healthy and mastitic cows and to further investigate whether these parameters can be used as a tool for identifying cows at higher risk of developing mastitis. Blood samples from 110 dairy cows from two commercial farms were obtained at dry-off, calving, and 30 days post-partum. Healthy cows formed group A (n = 90) and mastitic cows B (n = 20). Blood serum was obtained by centrifugation, and the aforementioned parameters were determined. A general linear model was used for analysing the associations among the determined blood parameters, the health of the animals’ udder, and the sampling time. ROS and OSi values were higher (P < 0.001) by a respective 14% and 26%, and SAC values lower (P < 0.001) by 10% in group B than in group A at calving. ROC curve analysis revealed that all determined parameters at calving and α-T at dry-off and 30 days post-partum had excellent or acceptable predicting ability for mastitis incidence. This information provides a tool for early identification of cows at high risk of developing mastitis, allowing the implementation of intervention strategies.

Atrial fibrillation may potentially contribute to oxidative stress to a greater extent than chronic heart failure. The aim of the study was to compare the serum total antioxidant capacity and enzymatic antioxidant defence of dogs with chronic heart failure and atrial fibrillation with those of subjects with chronic heart failure and sinus rhythm and healthy controls. A total of 33 dogs were divided into three groups: dogs with chronic heart failure and atrial fibrillation (CHF + AF; n = 12), chronic heart failure and sinus rhythm (CHF + SR; n = 9), and healthy controls (n = 12). Serum total antioxidant capacity (TAC), serum CuZn-superoxide dismutase (SOD) and catalase, and plasma glutathione peroxidase (GPx) activity were determined. SOD activity and serum TAC were significantly lower in the study groups than in control animals. Catalase activity was significantly higher and plasma GPx activity significantly lower in dogs with CHF + AF compared with the CHF + SR and control dogs. The results suggest that chronic heart failure in dogs significantly impacts the serum TAC and the antioxidant enzymatic defence, while plasma GPx activity is markedly lower in dogs with chronic heart failure and atrial fibrillation. The role of that imbalance needs further investigation.

Ochratoxin A (OTA) is a mycotoxin notably produced by Aspergillus and Penicillium spp. Bacillus subtilis fermentation extract (BSFE) contains specific enzymes which hydrolyse OTA. This study evaluated the efficiency of BSFE in ameliorating the immunotoxic and nephrotoxic effects of OTA in broiler chickens. Day-old broiler chicks were divided equally into four groups of ten: control, OTA (0.5 mg/kg feed), BSFE product (1 mL/L water) and OTA + BSFE at the same concentrations. The chicks were vaccinated against avian influenza, Newcastle disease, and infectious bronchitis, and lymphoproliferation was induced in all birds by phytohaemagglutinin-P (PHA-P). Serum samples were taken before sacrifice and organ tissue samples were taken after, in which renal function biomarkers were assayed and the presence of OTA residue was evaluated by high-performance thin-layer chromatography. Protein markers of apoptosis were determined by qPCR, and tissue lesions were examined histopathologically. Exposure to OTA significantly decreased the antibody response to the vaccines and the lymphoproliferative response to PHA-P, and significantly elevated the renal function indicators: serum urea, uric acid and creatinine. It also induced oxidative stress (reduced catalase activity and glutathione concentration), lipid peroxidation (increased malondialdehyde content), apoptosis (increased Bax and Caspase-3 and decreased Bcl-2 gene levels) and pathological lesions in kidney, bursa of Fabricius, spleen and thymus tissue. Residues of OTA were detected in the serum and tissue. BSFE mitigated most of these toxic effects. BSFE counters OTA-induced immunotoxicity and nephrotoxicity because of its content of carboxypeptidase and protease enzymes.

There is a balance between oxidative stress, antioxidant capacity and immune response. Their roles in physiological and behavioural mechanisms are important for the maintenance of the organism’s internal equilibrium. This study aimed to evaluate the antioxidant effects of the exogenous alga Spirulina platensis (Arthrospira platensis) in a stress-induced rat model, and to describe its possible mechanism of action. Thirty-six adult male Sprague Dawley rats were separated into four groups: control (C), stress (S), S. platensis (Sp), and S. platensis + stress (SpS). The rats in groups Sp and SpS were fed with 1,500 mg/kg b.w./day Spirulina platensis for 28 days. All rats were exposed to prolonged light phase conditions (18 h light : 6 h dark) for 14 days. The SpS and S groups were exposed to stress by being kept isolated and in a crowded environment. Blood samples were obtained by puncturing the heart on the 28th day. The effect of stress on serum corticosterone, oxidative stress markers (TOS, TAC, PON1, OSI) and immunological parameters (IL-2, IL-4, IFN-ɣ) were tested. Also, the brain, heart, intestines (duodenum, ileum, and colon), kidney, liver, spleen, and stomach of the rats were weighed. Serum corticosterone levels were higher in the S group than in the C group, and significantly lower in the SpS group than in the S group. Mean total antioxidant capacity were lower in the S group than in the C group, and Spirulina reversed this change. Although not significantly different, IL-2 was lower in the S group than in the C group. However, in the SpS group, IL-2 increased due to Spirulina platensis mitigating effects of stress. Male rats fed a diet with Spirulina platensis could experience significantly milder physiological changes during stress, although stress patterns may be different. Exogenous antioxidant supplements merit further investigation in animals and humans where the endogenous defence mechanism against stress may not be sufficient.

The aim of the study was to investigate the mitigative effects of bisoprolol (BIS) in cadmium-induced myocardial toxicity on oxidative stress and its inhibitive effect on nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) signalling in rats. Male albino Wistar rats were assigned to control, Cd, BIS 2 (2 mg/kg b.w.) and BIS 8 (8 mg/kg b.w.) groups with nine rats in each. Over four weeks, the control group was administered 1% gum acacia, all other groups received 3mg/kg b.w. CdCl₂ dissolved in distilled water, and the BIS groups were additionally given bisoprolol in gum acacia. Blood samples were collected for biochemical estimations. Blood pressure and serum biomarker (lactate dehydrogenase, aspirate transaminase, alanine transferase and creatine kinase-MB, enzyme (superoxide dismutase, lipid hydroxy peroxidase, catalase and malondialdehyde), and tumour necrosis factor alpha (TNF-α) concentrations were measured. Western blot analysis was conducted for NF-κB and glutathione S-transferase (GST). After sacrificing the rats, cardiac tissue samples were examined histopathologically. Our findings pointed to a significant decrease (P < 0.05) in the studied serum biomarkers and levels of the relevant enzymes in the BIS 8 group compared to the Cd group. A significant decrease (P < 0.05) in NF-kB p65 expression and TNF-α levels was noted in the BIS 8 group relative to the BIS 2 and Cd groups, indicating a reduction at a higher dose. In microscopy, histopathological changes in the cardiac muscles of the BIS 8 group were evident compared to those of the Cd group. BIS seemed to have protective effects against cardiac injury induced by cadmium and could be considered a novel therapeutic drug and prognostic biomarker in the pathology of the many cardiovascular diseases caused by heavy metal intake.

For many years, scientists have been pursuing research on skeletal muscle ageing both in humans and animals. Studies on animal models have extended our knowledge of this mechanism in humans. Most researchers agree that the major processes of muscle ageing occur in the mitochondria as the major energy production centres in muscle cells. It is believed that decisive changes occur at the enzymatic activity level as well as in protein synthesis and turnover ability. Deregulation of ion channels and oxidative stress also play significant roles. In particular, in recent years the free radical theory of ageing has undergone considerable modification; researchers are increasingly highlighting the partly positive effects of free radicals on processes occurring in cells. In addition, the influence of diet and physical activity on the rate of muscle cell ageing is widely debated as well as the possibility of delaying it through appropriate physical exercise and diet programmes. Numerous studies, especially those related to genetic processes, are still being conducted, and in the near future the findings could provide valuable information on muscle ageing. The results of ongoing research could answer the perennial question of whether and how we can influence the rate of ageing both in animals and humans.

The purpose of this study was to investigate the protective effect of hydrogen-rich saline (HRS) against liver ischaemia-reperfusion combined resection injury. Eighteen miniature pigs were randomly divided into three groups: a sham operated group (sham group, laparoscopic liver ischaemia-reperfusion combined resection injury group (IRI group), and a hydrogen-rich saline intervention group (IRI + HRS group). Samples of hepatic tissue and serum were collected at the time of reperfusion and then 3 h, 1 d, and 3 d post reperfusion. Liver function, oxidative stress, autophagy-related mRNA genes, and protein expression were evaluated. Changes in cell and tissue ultrastructure were examined by transmission electron microscopy. Compared with the sham group, the level of autophagy of hepatocytes increased in the IRI and IRI + HRS groups, corresponding to high oxidative stress and severe liver function injury. Liver function, antioxidant content, autophagy levels, and liver injury were improved after intervention with HRS in the IRI + HRS group compared with the IRI group. Intervention with hydrogen-rich saline could exert a protective effect against liver ischaemia-reperfusion combined resection injury through the reduction of oxidative stress and hepatocyte autophagy.