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The present study aimed to assess the effects of replacing the starchy ingredients of concentrate by increasing the levels of sunflower oil on the production, composition, fatty acid profile, and evaluate the atherogenicity and thrombogenic index of Jersey cow's milk. Eight Jersey cows were arranged in a double Latin square and distributed in treatments consisting of supplementation with increasing levels of sunflower oil replacing the corn grain and wheat bran of concentrate, including the following: T0 (control diet), without sunflower oil and with 38 g ether extract (EE)/kg dry matter (DM); T1 = 65 g EE/kg DM; T2 = 86 g EE/kg DM; and T3 = 110 g EE/kg DM. The daily milk production was measured, and the corrected milk production was calculated. Milk samples were analyzed by infrared spectroscopy to determine fat, protein, lactose, and total solids, whereas the lipid profile was assessed by gas chromatography. Milk production, energy-corrected milk production, fat content, daily fat production, lactose, and total solids were not affected by the treatments. Protein, lactose, and total solids concentrations decreased. Short-, medium-, and odd-chain fatty acids decreased with an increase in sunflower oil levels. Conversely, linear increases in long-chain, monounsaturated, and polyunsaturated fatty acid concentrations were observed. There were significant increases in stearic and elaidic acids and conjugated linoleic acid isomers, especially in vaccenic and rumenic acids. There was a positive effect on the milk atherogenicity, thrombogenicity, and nutraceutical indices. Dietary supplementation with sunflower oil changes the milk FA profile, decreases the atherogenicity and the thrombogenicity indices, and improve the nutraceutical index up to the addition of 86 g EE/kg DM de sunflower oil in the diets of Jersey cows., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

The objective of this study was to evaluate the effects of three finishing systems based on concentrate and legume-grass pasture on beef. Steers were finished for 91 days with an exclusively whole corn grain-based (GRAIN) diet, grazed on legume-grass pasture plus 1.4% of body weight of whole corn grain supplementation (SUPP), or grazed on legume-grass pasture (PAST) only. Lipid and myoglobin oxidation, pH, objective color, and α-tocopherol concentrations were evaluated on M. longissimus thoracis steaks. Dietary treatments did not affect pH and minimally affected protein carbonylation. Steaks from steers fed GRAIN were less red, showed higher lipid oxidation during retail display, and higher metmyoglobin formation from day 7 to 13 when compared to PAST. Levels of α-tocopherol were higher in steaks from steers fed diets containing legume and grass. Inclusion of roughage in finishing diets is essential to maintain retail color and prevent lipid and myoglobin oxidation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)