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Simple Summary: Broiler chickens are often exposed to various nutritional and environmental stressors that negatively impact their productivity and overall health. These stressors, such as oxidized diets and high ambient temperatures, increase the risk of oxidative stress, which can affect meat quality and increase production costs. While the harmful effects of high n-3 polyunsaturated fatty acid (PUFA) levels and heat stress on broiler meat quality parameters have been documented, less is known about the combined effects of both these stressors. Antioxidant supplementation could play a key role in improving antioxidant defense and preventing oxidative damage to meat. Our study confirmed that dietary enrichment with 5% linseed oil and cyclic heat stress negatively affected the quality and oxidative stability of broiler breast meat, although no interactions between the stressors were found. In addition, high levels of antioxidants were found to improve meat quality and prevent oxidative damage to broiler meat. This study investigated the individual and combined effects of a high dietary n-3 PUFA intake and cyclic heat stress (HS) on the carcass characteristics, meat quality, and oxidative stability of broiler breast meat and the potential of antioxidant supplementation (vitamins E, C, and selenium) to mitigate these effects. A total of 192 one-day-old male Ross 308 broilers were randomly assigned to 24 pens within two controlled environment chambers and fed with the following diets: a basal diet low in antioxidants according to NRC recommendations (NRC group), a basal diet according to Aviagen recommendations additionally supplemented with 200 IU/kg vitamin E, 250 mg/kg vitamin C, and 0.15 mg/kg selenium (HAOX group), and these two diets further supplemented with 5% linseed oil (NRC N-3 and HAOX N-3 groups). On day 22, the broilers were exposed to the following two environmental conditions: thermoneutral (TN, 21 °C) or cyclic HS (HS, 34 ± 1 °C, 7 h/d) in a 2 × 2 × 2 factorial design. A high intake of n-3 PUFAs significantly decreased growth performance, dressing percentage, and breast yield, while the incidence of pale, soft, and exudative (PSE) meat characteristics and malondialdehyde (MDA) levels increased. Cyclic HS reduced body weight (BW) and average daily feed intake (ADFI), but had limited effects on meat quality. No interactions between n-3 PUFAs and HS were observed for any measurements. High antioxidant supplementation increased breast yield, improved meat quality, and reduced oxidative stress, as evidenced by an enhanced antioxidant activity and lower MDA levels. In conclusion, n-3 PUFAs had a negative effect on both the carcass characteristics and meat quality of broilers, while HS primarily affected only carcass characteristics, with neither stressor having severe adverse effects. High levels of antioxidants could mitigate the negative effects of dietary- and heat-induced oxidative stress by enhancing the oxidative stability of broiler meat. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The objective of this study was to establish the effects of chestnut tannin extract or vitamin E added to linseed oil-enriched diets on growth performance, meat quality, and intestinal morphology of broiler chickens. A total of 240 day-old Ross 308 male broiler chicks were included in trial. 5% of cold-pressed linseed oil was included in finisher diets (21–40 days), and three feeding treatments with four replicates were formed: finisher without additives; finisher + 200 IU vitamin E/kg; finisher + 500 mg/kg of chestnut wood tannin extract. No significant influence of treatments was established on body weight or feed conversion ratio. A negative effect on feed intake (p < 0.05) was found in the vitamin E group. The addition of vitamin E increased the dressing percentage (p < 0.05) and increased the breast meat yield (p < 0.01) compared to the control group. No significant effects were found on the water holding capacity or pH of breast meat. The highest level of AST (p < 0.01) and ALT (p < 0.05) was recorded in vitamin E group. The addition of chestnut tannin extract in feed increased villus height, villus height: crypt depth ratio, and villus area compared to the other two groups (p < 0.05). It can be concluded that vitamin E supplementation improves carcass percentage and breast meat yield, while chestnut tannins improve the intestinal morphology of broiler chickens when added to oil-enriched diets. [ABSTRACT FROM AUTHOR]

Simple Summary: High ambient temperatures present challenging environmental factors in the poultry meat industry, causing heat stress. Heat stress impairs animal health and welfare, growth performance, and productivity, and deteriorates meat quality and its oxidative stability, resulting in economic losses. To mitigate the negative effects of heat stress, several nutritional strategies have been proposed, with vitamin and mineral supplementation being one of the most promising. Several studies reported that the addition of vitamins E and C, as well as selenium, to broiler diets improved the production performance and meat quality of broilers reared under heat stress. Due to the synergistic effects of these antioxidants against the oxidative damage to lipids, combined supplementation could be even more effective in alleviating the symptoms of heat stress on meat quality than supplementation alone, but this has not yet been studied. The results of the present study indicate positive effects of the supplementation with vitamin E on the oxidative stability of breast meat. However, no synergistic effects of the added antioxidants on the measured parameters were observed. 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The reactivity of tocopherols with 2,2-diphenyl-1-picrylhydrazyl (DPPH) was studied in model systems in order to establish a method for quantifying vitamin E in plant oils. The method was optimized with respect to solvent composition of the assay medium, which has a large influence on the course of reaction of tocopherols with DPPH. The rate of reaction of a-tocopherol with DPPH is higher than that of ?-tocopherol in both protic and aprotic solvents. In ethyl acetate, routinely applied for the analysis of antioxidant potential (AOP) of plant oils, reactions of tocopherols with DPPH are slower and concentration of tocopherols in the assay has a large influence on their molar reactivity. In 2-propanol, however, two electrons are exchanged for both a- and ?-tocopherols, independent of their concentration. 2-propanol is not toxic and is fully compatible with polypropylene labware. The chromatographically determined content of tocopherols and their molar reactivity in the DPPH assay reveal that only tocopherols contribute to the AOP of sunflower oil, whereas the contribution of tocopherols to the AOP of linseed oil is 75%. The DPPH assay in 2-propanol can be applied for rapid and cheap estimation of vitamin E content in plant oils where tocopherols are major antioxidants. [ABSTRACT FROM AUTHOR]

This study examined the percentage and stable isotope ratios of fatty acids in milk to study seasonal, year, and regional variability. A total of 231 raw cow milk samples were analyzed. Samples were taken twice per year in 2012, 2013, and 2014, in winter and summer, covering four distinct geographical regions in Slovenia: Mediterranean, Alpine, Dinaric, and Pannonian. A discriminant analysis model based on fatty acid composition was effective in discriminating milk according to the year/season of production (86.9%), while geographical origin discrimination was less successful (64.1%). The stable isotope composition of fatty acids also proved to be a better biomarker of metabolic transformation processes in ruminants than discriminating against the origin of milk. Further, it was observed that milk from Alpine and Mediterranean regions was healthier due to its higher percentage of ω-3 polyunsaturated fatty acid and conjugated linoleic acid. [ABSTRACT FROM AUTHOR]

Simple Summary: Olive polyphenols exert many favorable properties, such as an antioxidative effect in humans, but are poorly studied in animals, especially in pigs. Therefore, we conducted a trial including olive leaf extract (OLE), which is rich in polyphenols, in pigs fed a linseed oil-enriched diet, which is a known cause of postprandial oxidative stress. OLE exerted some antioxidative effects in piglets fed a polyunsaturated fatty acid (PUFA)-rich diet without any negative effects, even when included in a higher concentration than that proposed for humans. Additionally, the inclusion of OLE did not compromise the zootechnical performance of the piglets as in the case of the dietary inclusion of olive leaves. Therefore, OLE could be used as an effective feed additive for beneficial effects on intestinal health and meat quality, among others. 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 F2-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. [ABSTRACT FROM AUTHOR]