V svetovnem merilu perutninsko meso predstavlja cenovno dostopen in kakovosten vir beljakovin, zato se je v zadnjih desetletjih povečala njegova prireja. Slednje smo dosegli z intenzivno selekcijo ...pitovnih piščancev na hitro rast, učinkovitejše izkoriščanje krme, povečan delež prsne mišičnine in manjši delež trebušne maščobe. Na drugi strani so tako intenzivna selekcija in zahteve po večji prireji, kot tudi nekateri zunanji stresni dejavniki, ki vključujejo neželene spremembe v okolju, prehranskem režimu, tehnologiji reje in nepravilne postopke ravnanja z živalmi pred zakolom, povzročili večjo dovzetnost živali za oksidativni stres, ki poslabšuje senzorične in tehnološke lastnosti perutninskega mesa. Posledice hitrega povečevanja prsne mišičnine pri pitovnih piščancih in intenzivne tehnologije reje se kažejo v naraščajočem trendu pojavnosti različnih neželenih sprememb piščančjega mesa oziroma miopatij. Med najpogostejše miopatije spadajo miopatija globoke prsne mišice, bledo, mehko in vodeno meso, bela progavost prsne mišice, olesenelost prsne mišičnine ter špagetasto meso, ki prizadenejo predvsem veliko prsno mišico in poslabšujejo njene senzorične in tehnološke lastnosti. Prav tako omenjene spremembe prsne mišičnine poslabšujejo kakovost in prehransko vrednost mesa ter vplivajo na sprejemljivost mesa za potrošnike in nedvomno povzročajo ekonomske izgube v živilsko-predelovalni industriji.
The present study was conducted to investigate the effects of dietary supplementation with vitamin E, vitamin C, and Se, alone or in combination, on carcass characteristics, oxidative stability and ...meat quality parameters of breast meat from broilers exposed to cyclic heat stress (HS), and stored under different conditions. A total of 120 one-day-old male Ross 308 broilers were randomly assigned to six dietary treatments: NRC (minimal nutrition requirements), AVI (commercial nutritional recommendations for Ross 308 broilers), AVI + vitE (as AVI + 200 IU vitamin E/kg feed), AVI + vitC (as AVI + 250 mg vitamin C/kg feed), AVI + Se (as AVI + 0.2 mg Se/kg feed), and AVI + ECSe (as AVI + vitE + vitC + Se). From day 26 onwards, all birds were exposed to a high ambient temperature (31 °C) for 8 h per day. The results showed that dietary vitamin E alone or in combination with vitamin C and Se significantly increased the α-tocopherol content and decreased the malondialdehyde (MDA) content in breast meat. Although no obvious synergistic effects of the added antioxidants were observed, the addition of higher levels of vitamin E, vitamin C and Se to broiler diets had no adverse effects on carcass traits, oxidative stability and meat quality parameters when supplemented either alone or in combination.
An experiment in broilers was conducted to investigate the effect of olive (Olea europea) leaves and marigold (Calendula officinalis) petal extract supplementation on oxidative stress, ...characteristics of intestinal contents, and on the morphology of the small intestine. Oxidative stress was induced by a n-3 polyunsaturated fatty acids rich diet. 1-day-old male broiler chickens, Ross 308, were housed in a deep litter system. After the first 21 days, animals were randomly divided into three groups of 16 animals in two replicates and fed, until slaughter on day 39, a diet that contained 7% linseed oil. Control diet (Cont) remained unsupplemented, while both experimental diets were supplemented with olive leaves (OliveEx) or marigold petal (MarigEx) extracts. Oxidative stress was evaluated in blood and liver by measuring markers of lipid peroxidation (malondialdehyde (MDA), isoprostanes), rate of DNA damage in lymphocytes and in blood (comet assay, 8-hydroxy-2′deoxyguanosine (8-OHdG)), and activity of antioxidant and liver enzymes in blood. In different parts of the intestine, levels of short chain fatty acids (SCFA), and viscosity of intestinal contents were measured, and the health of the gastrointestinal tract was assessed using histological measurements. OliveEx significantly (p<0.05) decreased the MDA and 8-OHdG concentration in plasma, and the level of ethanoic acid in small intestinal contents and total SCFA in caecum, indicating improved oxidative status and increased microbial activity in the intestine. MarigEx significantly (p<0.05) decreased the rate of lymphocyte DNA damage and the crypt depth in duodenum, indicating potentially beneficial effects on the immune system and the health of the small intestine. In conclusion, dietary OliveEx and MarigEx supplementation improved some markers of oxidative stress and intestinal health. However, positive effects could be more pronounced in more unfavorable environmental conditions or in cases of diseases, but further studies are needed.
Inflammation and oxidative stress can contribute to the development and progression of heart failure. This study aimed to investigate the association between inflammatory and oxidative stress markers ...in dogs with congestive heart failure (CHF). Associations between the disease severity marker N-terminal pro-B-type natriuretic peptide (NT-proBNP) and markers of inflammation and oxidative stress were also determined.
Thirty-seven dogs with cardiovascular diseases (dilated cardiomyopathy, DCM (16 dogs), myxomatous mitral valve disease, MMVD (21 dogs)) and ten healthy dogs were included in this prospective study. The patients were further divided into groups with (26) and without CHF (11). We found a significantly higher serum concentration of C-reactive protein (P = 0.012), white blood cell (P = 0.001), neutrophil (P = 0.001) and monocyte counts (P = 0.001) in patients with CHF compared to control dogs. The concentration of tumor necrosis factor-alpha (TNF-α) was significantly higher in patients with CHF compared to patients without CHF (P = 0.030). No significant difference was found in most of the measured parameters between MMVD and DCM patients, except for glutathione peroxidase (GPX) and NT-proBNP. In patients with CHF, TNF-α correlated positively with malondialdehyde (P = 0.014, r = 0.474) and negatively with GPX (P = 0.026, r = - 0.453), and interleukin-6 correlated negatively with GPX (P = 0.046, r = - 0.412). NT-proBNP correlated positively with malondialdehyde (P = 0.011, r = 0.493). In patients without CHF none of the inflammatory and oxidative stress markers correlated significantly. Furthermore, in the group of all cardiac patients, GPX activity significantly negatively correlated with NT-proBNP (P = 0.050, r = - 0.339) and several markers of inflammation, including TNF-α (P = 0.010, r = - 0.436), interleukin-6 (P = 0.026, r = - 0.382), white blood cell (P = 0.032, r = - 0.369), neutrophil (P = 0.027, r = - 0.379) and monocyte counts (P = 0.024, r = - 0.386).
Inflammatory and oxidative stress markers are linked in canine CHF patients, but not in patients without CHF. These results suggest complex cross communication between the two biological pathways in advanced stages of CHF.
Over the last decade, the two-phase centrifugation system for olive-oil extraction has become dominant in Slovenia. There are many suggestions for the exploitation of two-phase OMW, but among the ...suggested methods, direct spreading on agricultural land appears to be operationally simple and economically feasible for Slovenia. As there is little information available about two-phase OMW produced in the northern Mediterranean regions, the aim was to determine its composition and evaluate its use as a soil amendment in olive groves. This study shows that the characteristics of two-phase olive-mill waste produced in northern Mediterranean regions are similar to those of other countries. In addition, the calcareous characteristics of the Mediterranean soil can reduce its phytotoxic effects and might thus represent a natural system for olive-mill waste treatment. Phenolic compounds in the two-phase olive-mill waste are rapidly decomposed, and the soil has a high buffering capacity. Furthermore, the results of the soil analysis also showed some effects on the soil properties, such as a significant increase in K2O and soil organic carbon. The combined application of two-phase olive-mill waste and mineral fertilizer to olive groves on eutric cambisols has positive effects on the physical, chemical and biochemical properties of the soil.
The aim of the current study was to assess the antioxidative effects of the dietary supplementation of olive leaf extract (OLE) in different concentrations compared to those of vitamin E in piglets ...under conditions of dietary n-3 PUFA-induced oxidative stress. Forty-eight castrated male piglets (10.6 ± 0.99 kg) were fed the following experimental diets: Cont- (low-fat diet, no supplement), Cont+ (high linseed oil diet, no supplement), Vit-E (as Cont+, 105 IU vitamin E/day), OLE-1 (as Cont+, 3.84 mg hydroxytyrosol equivalents (HEQs)/day), OLE-2 (as Cont+, 38.4 mg HEQ/day), and OLE-3 (as Cont+, 96 mg HEQ/day). After 21 days of feeding, the experimental diets, blood and urine samples were collected to assess the extent of the oxidative stress. Results indicated that diet OLE-1 lowered the activity of gamma-glutamyl transferase, protected DNA (measured as DNA tail %) and altered urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG). Dietary vitamin E lowered the levels of urinary F
-isoprostanes, as well as of plasma malondialdehyde and γ-tocopherol, but raised the plasmatic α-tocopherol and altered the level of urinary 8-OHdG. In conclusion, only minor positive effects of dietary OLE on the oxidative stress parameters were observed. Additionally, OLE did not show concentration dependence.
The aim of this study was to investigate the effects of olive leaf and marigold extracts on the apparent total tract digestibility (ATTD) of the principal nutrients and energy, as well as on mineral ...utilization (Ca, P, Mg, Mn, Fe, Cu and Zn) in relation to bone characteristics in broilers fed walnut- or linseed oil-supplemented diets. Thirty-six 12-day-old commercial broilers Ross 308 were reared in metabolic cages, assigned to one of the six dietary treatments (3 × 2 factorial design): three supplements (not supplemented, olive leaf extract, or marigold extract), and two oils (walnut or linseed oil). The results showed that the marigold extract reduced Zn and P balances and tended to lower the balance of ash and Mg, and the ATTD of Zn and Mg. Diets with linseed oil increased the ATTD of acid detergent fiber and reduced the ATTD of the organic residue and Cu. No differences in the bone characteristics of tibia were observed between treatments. These results indicated that the inclusion of marigold extract had a negative effect on the Zn and P balance, and that neither extract had any major effect on the digestion and utilization of energy and other investigated nutrients, or on bone mineralization, irrespective of the oil source included in the diet.
It is widely accepted that olive (Olea europaea L.) polyphenols (OP) have many favourable properties (e.g. antioxidative, antimicrobial, antifungal). OP can improve the growth and nutrient ...digestibility of animals via affecting digestion and health, even though they could negatively affect the mineral absorption by forming insoluble complexes with minerals in the intestine. In the present study, the effects of a dietary olive leaves extract (OLE) on nutrient digestibility in pigs were studied. Twenty-four weaned castrated male piglets were fed a no supplemented (C) or a supplemented diet with three different levels of OLE (O1, O2 and O3: 3.84 mg, 38.4 mg, 96 mg hydroxytyrosol equivalents/day, respectively). Retention and apparent total tract digestibility (ATTD) of dry matter (DM), crude protein (CP), crude fat (CF), organic matter (OM), nitrogen free extract (NFE), ash, neutral (NDF) and acid detergent fibres (ADF), gross energy (GE), Ca, P, Mg, Fe, Cu, Zn, K and Na were measured. Results showed that OLE lowered the retention of Fe and K, and revealed a numerical tendency to lower the retention of Cu and ATTD of Fe and Cu. In conclusion, a low dietary supplementation of OLE has no effect on the digestibility and retention of major nutrients, although some minor negative effects on mineral digestibility can be present.
The gastrointestinal tract of broilers is susceptible to oxidative stress induced by heat stress (HS) and diet, which can be mitigated by the supply of exogenous vitamins and antioxidants. The aim of ...this study was to compare the extent of the effects of cyclic HS, and high levels of polyunsaturated fatty acids (PUFA) (HP) on gut health. It also aimed to investigate whether additional supplementation with vitamins E, C and selenium (HA) is required to support gut health under these conditions. In the present study, 192 one-day-old male Ross 308 broilers were randomly divided into eight experimental groups. Exposure to HS and HP significantly (p < 0.001) decreased villus height and villus-to-crypt ratio in the duodenum, while no differences were observed in the jejunum and ileum. In addition, oxidative stress in the liver, indicated by increased malondialdehyde (MDA) levels, was increased in the HP groups (p < 0.0001), while the HA groups had a positive effect on lowering MDA levels. The results confirm that cyclic HS and HP induce oxidative stress that damages the structure of intestinal morphology and that supplementation with HA could be a potential approach to mitigate the negative effects of these stressors.
Myxomatous mitral valve degeneration (MMVD) is the most common naturally occurring heart disease in dogs. There is a lack of data on antioxidant status and oxidative damage in dogs with MMVD stage B1 ...according to the American College of Veterinary Internal Medicine (ACVIM B1). The aim of this study was to investigate antioxidant status (plasma vitamin E, lipid-standardized vitamin E (LS-VitE), antioxidant capacity of lipid-(ACL) and water-soluble antioxidants, whole blood glutathione peroxidase and erythrocyte superoxide dismutase), and lipid peroxidation malondialdehyde (MDA) in dogs with MMVD ACVIM B1. Serum cholesterol and triglyceride concentrations were measured to calculate LS-VitE. Fourteen dogs with MMVD ACVIM B1 and 12 control dogs were included in the study. Dogs with MMVD had significantly higher vitamin E, ACL, MDA, and cholesterol concentrations and significantly higher LS-VitE values than control dogs. No significant correlations between MDA and antioxidant parameters were determined in either group. In conclusion, oxidative damage to lipids is already present and the antioxidant status is altered but not depleted in dogs with MMVD ACVIM B1. The antioxidant response to increased oxidative damage consists mainly of the activation of fat-soluble antioxidants. Further research is needed to evaluate the efficacy and targets of early antioxidant supplementation to prevent or ameliorate oxidative stress and mitigate disease progression in dogs with early-stage MMVD.