TITLE:
Feeding Polyunsaturated Supplements to Grazing Dairy Cows Improve the Healthy Value of Milk Fatty Acids
AUTHORS:
Gerardo Antonio Gagliostro, Daniel Alberto Garciarena, María Alejandra Rodriguez, Liliana Elisabet Antonacci
KEYWORDS:
Grazing Dairy Cow, Milk Fatty Acids, Conjugated Linoleic Acid
JOURNAL NAME:
Agricultural Sciences,
Vol.8 No.8,
August
18,
2017
ABSTRACT: The objective of the experiment was to improve the healthy value of milk fatty acids (FA) by feeding sunflower oil (SO) or sunflower seed (SS) combined or not with fish oil (FO) to grazing dairy cows. Four Holstein cows (515 ± 80 kg liveweight) in late lactation (230 days postpartum) fitted with ruminal cannulae were allotted to a 4 × 4 Latin square design with factorial arrangement of treatments: SS = 1.9 kg dry matter (DM)/cow/d of SS; SO = 0.8 kg/cow/d of SO; SS-FO = SS + 0.24 kg/cow/d FO and SO-FO = SO + 0.24 kg/FO. Cows grazed a high quality pasture offered at 11 kg DM/cow/day. After the afternoon milking cows also received 5.6 kg DM/cow of corn silage and during each milking time cracked corn grain (1.3 kg DM/cow) mixed with a mineral-vitamin premix was fed. Oils and SS were introduced via ruminal cannulae and SS was fed roughly grounded. Milk yield tended (p 12:0, 51% for C14:0 and 29% for C16:0. Atherogenicity index (AI) of milk was reduced particularly in SS-FO. Basal concentration of cis-9, trans-11 C18:2 (CLA) in milk was 1.39 g/100g FA and increased (p