Impact of US Brown Swiss genetics on milk quality from low-input herds in Switzerland: Interactions with grazing intake and pasture type

• Published in: Food chemistry Vol. 175; pp. 609 - 618
• Main Authors: Stergiadis, S., Bieber, A., Franceschin, E., Isensee, A., Eyre, M.D., Maurer, V., Chatzidimitriou, E., Cozzi, G., Bapst, B., Stewart, G., Gordon, A., Butler, G.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15-05-2015
• Subjects: Animal Feed; Animals; Brown Swiss; Cattle - genetics; Dairying - methods; Fatty acid; Fatty Acids - analysis; Fatty Acids, Omega-3 - analysis; Female; Grassland; Hybridization, Genetic; Low-input; Milk; Milk - chemistry; Original Braunvieh; Fatty acid; Original Braunvieh; Milk; Low-input; Brown Swiss
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2014.11.079

•Breeding by feeding interactions in milk quality were studied on low-input dairy farms.•Crossbreeding with traditional breeds did not affect milk yield from low-input systems.•Grazing natural pastures improved milk fatty acid profile.•Omega-3 content was maximised by combining traditional genetics with high grazing diets.
This study investigated the effect of, and interactions between, contrasting crossbreed genetics (US Brown Swiss [BS]×Improved Braunvieh [BV]×Original Braunvieh [OB]) and feeding regimes (especially grazing intake and pasture type) on milk fatty acid (FA) profiles. Concentrations of total polyunsaturated FAs, total omega-3 FAs and trans palmitoleic, vaccenic, α-linolenic, eicosapentaenoic and docosapentaenoic acids were higher in cows with a low proportion of BS genetics. Highest concentrations of the nutritionally desirable FAs, trans palmitoleic, vaccenic and eicosapentaenoic acids were found for cows with a low proportion of BS genetics (0–24% and/or 25–49%) on high grazing intake (75–100% of dry matter intake) diets. Multivariate analysis indicated that the proportion of OB genetics is a positive driver for nutritionally desirable monounsaturated and polyunsaturated FAs while BS genetics proportion was positive driver for total and undesirable individual saturated FAs. Significant genetics×feeding regime interactions were also detected for a range of FAs.