Consumption of thermally-oxidized sunflower oil by chicks reduces α-tocopherol status and increases susceptibility of tissues to lipid oxidation

Abstract

The effect of heated sunflower oil consumption on u-tocopherol status, fatty acid composition and oxidative stability of chicken tissues was investigated. Chicks were fed on diets containing (g/kg): fresh sunflower oil (FSO) 40, heated sunflower oil (HSO) 40 or heated sunflower oil (40) supplemented with a-tocopheryl acetate (HSE) to a similar u-tocopherol concentration as the FSO diet. Concentrations of a-tocopherol in tissues of chicks fed on HSO and HSE were significantly lower than those of chicks fed on FSO. Significant correlations were observed between plasma u-tocopherol concentration and the a-tocopherol Concentrations of other tissues (v 2 0.67, P < 0.005) and between log plasma a-tocopherol and plasma thiobarbituric acid-reacting substances (TBARS) concentrations (v -0,851, P < 0.001). The concentrations of TBARS in tissues of chicks fed on the various diets were generally very similar before stimulation of peroxidation with Fe-ascorbate. Susceptibility of tissues to Fe-ascorbate-induced lipid peroxidation was increased by feeding HSO. Supplementation with u-tocopheryl acetate reduced susceptibility to lipid oxidation to varying degrees, depending on the tissue. The results suggest that chronic ingestion of oxidized lipids may compromise free-radical-scavenging activity in vivo by depleting u-tocopherol in the gastrointestinal tract, or possibly in plasma and other tissues.

Use of recovered frying oils in chicken and rabbit feeds: effect on the fatty acid and tocol composition and on the oxidation levels of meat, liver and plasma

“…Previous studies attributed the reduction of tissue aT content also to a loss of this antioxidant in the gastrointestinal tract as a result of its reaction with radical species, thereby reducing the amount available for absorption (Sheehy et al, 1993). However, this Tissue lipids in chicken and rabbit fed frying oils was more evident when fats presented a higher content of primary oxidation compounds than in our study (Sheehy et al, 1994;Tres et al, 2010b). These results highlight the relevance of a complete characterization of feed ingredients, including their composition and oxidation status, as these two parameters might affect the nutritional characteristics of meat and other animal products.…”

Dietary n-6- or n-3-rich vegetable fats and α-tocopheryl acetate: effects on fatty acid composition and stability of rabbit plasma, liver and meat

“…Dietary supplementation with TA (100 mg/kg) increased the aT content in rabbit plasma by 2.3-fold, and the content in liver and meat by 3-fold (Table 4), according to previous literature in rabbit (Castellini et al, 1998 andOriani et al, 2001;Lo Fiego et al, 2004) and other animal species (Sheehy et al, 1994;Russell et al, 2004;Bou et al, 2006a). Figure 1 Ratio between long-chain n-6 fatty acids synthesized from linoleic acid and linoleic acid (in black), and ratio between long-chain n-3 fatty acids synthesized from linolenic acid and linolenic acid (in white), in rabbit plasma, liver and meat.…”

“…Furthermore, positive correlations were found among the aT content in plasma, liver and meat (Table 5). This suggests that aT content in plasma responds to feed aT content and reflects the aT status of tissues (Sheehy et al, 1994;Castellini et al, 2001;Oriani et al, 2001).…”

Dietary supplementation of pyrroloquinoline quinone disodium protects against oxidative stress and liver damage in laying hens fed an oxidized sunflower oil-added diet

“…The growth depression of broiler chicks fed with heated sunflower oil was probably due to the combined effect of oxidation products and a lower α-tocopherol content in the diet as suggested by Sheehy et al (1994). In the current study, although the Vit E and α-tocopherol levels of sunflower oil were decreased after thermal heating, their contents in the oxidized oil diet were comparable to the fresh oil diet.…”

“…No significant difference was observed in other performance items among the different groups, probably because of lower oxidation levels and a shorter period of feeding with oxidized oil as previously reported in broilers and fish (Yuan et al, 2014). Furthermore, Sheehy et al (1994) and López-Varela et al (1995) noted that feeding heated sunflower oil reduced weight gain in broiler chicks, and decreased feed efficiency ratio in rats, respectively. The contents of total polar compounds, peroxide value and lipid peroxidation products of heated sunflower oil they used were higher than that in the current study, which suggests that the oil used in our study was only moderately oxidized.…”