Milk composition and fatty acids profile of grazing dairy cows after supplementation with cottonseed and linseed
- Roca-Fernández A.I 1
- Antonio González-Rodríguez 1
- Orlando Pablo Vázquez-Yáñez 1
- José Antonio Fernández-Casado 2
- 1 Agrarian Research Centre of Mabegondo. PO Box 10, 15080 La Coruña, Spain
- 2 Agrarian and Fitopathologic Laboratory of Galicia. PO Box 365, 15640 La Coruña, Spain
Verlag: European Grassland Federation
ISBN: 978-3-902559-65-4
Datum der Publikation: 2011
Seiten: 154-156
Art: Konferenz-Beitrag
Zusammenfassung
7KHGLHWRIUXPLQDQWVLQÀXHQFHVWKHLUPLONFRPSRVLWLRQDQGIDWW\DFLG )$ SUR¿OH7KHHIIHFWof supplementation at pasture with two sources of forage (grass+silage (S) compared to ‘allgrazing’ grass (G)), and two types of concentrate (C, cottonseed and L, linseed) differing in)$SUR¿OHRIWKHWZRRLOVHHGFRPSRQHQWVZDVH[DPLQHGLQIRXUJURXSV 6&6/*&DQG*/ of autumn-calving Holstein-Friesian cows (n = 50). Milk yield and composition were determined across the main grazing season. The ‘all grazing’ treatments produced more milk, withhigher urea content, than the silage-supplemented grazing treatments, despite lower proteinDQGIDW7KHIRUDJHVRXUFHKDGDJUHDWHUHIIHFWRQPLON)$SUR¿OHWKDQWKHW\SHRIFRQFHQWUDWHused. The group of cows grazing all day had lower levels of short- and medium-chain FAthan those at grass-plus-silage. Higher content of long-chain (mono- and poly-unsaturated)FA was observed in milk from cows grazing all day. Daily intake of fresh grass was a decisivefactor for the highest conjugated linoleic acid (CLA) content. The addition of cottonseed inthe concentrate showed higher levels of long chain and mono-unsaturated FA than the use oflinseed. High reliance on grass at farm level would be a good tool to increase the CLA contentLQPLONIDWDQGJHWPRUHDGGHGYDOXHZLWKDQLPSURYHGPLON)$SUR¿OH