title: Effect of pasture versus indoor feeding systems on raw milk composition and quality over an entire lactation.
abstract: The aim of this study was to investigate the effects of different feeding systems on milk quality and composition. Fifty-four multiparous and primiparous Friesian lactating cows were divided into 3 groups (n=18) to study the effects of 3 feeding systems over a full lactation. Group 1 was housed indoors and offered a total mixed ration diet (TMR), group 2 was maintained outdoors on a perennial ryegrass pasture (referred to as grass), and group 3 was also grazed outdoors on a perennial ryegrass/white clover pasture (referred to as clover). Bulk milk samples were collected from each group at morning and afternoon milkings once weekly from March 11 to October 28 in 2015. Milk from pasture-fed cows (grass and clover) had significantly higher concentrations of fat, protein, true protein, and casein. The pasture feeding systems induced significantly higher concentrations of saturated fatty acids C11:0, C13:0, C15:0, C17:0, C23:0, and unsaturated fatty acids C18:2n-6 trans, C18:3n-3, C20:1, and C20:4n-6 and a greater than 2-fold increase in the conjugated linoleic acid C18:2 cis-9,trans-11 content of milk compared with that of the TMR feeding system. The TMR feeding system resulted in milks with increased concentrations of C16:0, C18:2n-6 cis, C18:3n-6 cis, C22:0 C22:1n-9, and C18:2 cis-10,trans-12. Principal component analysis of average fatty acid profiles showed clear separation of milks from the grazed pasture-based diets to that of a TMR system throughout lactation, offering further insight into the ability to verify pasture-derived milk by fatty acid profiling.
authors.affiliation: APC Microbiome Institute, University College Cork, Cork, Ireland; Department of Microbiology, University College Cork, Cork, Ireland; Department of Biosciences, Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.
authors.forename: Tom F
authors.initials: TF
authors.lastname: O'Callaghan
authors.affiliation: Animal and Grassland Research and Innovation Centre, Teagasc Moorepark, Fermoy, Cork, Ireland.
authors.forename: Deirdre
authors.initials: D
authors.lastname: Hennessy
authors.affiliation: Animal and Grassland Research and Innovation Centre, Teagasc Moorepark, Fermoy, Cork, Ireland; School of Biological Sciences, Queen's University, Belfast, BT7 1NN, United Kingdom.
authors.forename: Stephen
authors.initials: S
authors.lastname: McAuliffe
authors.affiliation: Department of Biosciences, Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.
authors.forename: Kieran N
authors.initials: KN
authors.lastname: Kilcawley
authors.affiliation: Animal and Grassland Research and Innovation Centre, Teagasc Moorepark, Fermoy, Cork, Ireland.
authors.forename: Michael
authors.initials: M
authors.lastname: O'Donovan
authors.affiliation: Animal and Grassland Research and Innovation Centre, Teagasc Moorepark, Fermoy, Cork, Ireland.
authors.forename: Pat
authors.initials: P
authors.lastname: Dillon
authors.affiliation: APC Microbiome Institute, University College Cork, Cork, Ireland; Department of Microbiology, University College Cork, Cork, Ireland.
authors.forename: R Paul
authors.initials: RP
authors.lastname: Ross
authors.affiliation: APC Microbiome Institute, University College Cork, Cork, Ireland; Department of Biosciences, Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland. Electronic address: catherine.stanton@teagasc.ie.
authors.forename: Catherine
authors.initials: C
authors.lastname: Stanton
mesh_terms: D000821:Animal Feed; D000818:Animals; D002417:Cattle; D004032:Diet / Q000662:veterinary; D005227:Fatty Acids; D005260:Female; D007774:Lactation; D008892:Milk / Q000737:chemistry*
chemical_list: D005227:Fatty Acids
keywords: dairy cow; diet; milk composition; pasture; total mixed ration