title: Sources of variability in lactational performance.
authors.affiliation: Edinburgh School of Agriculture.
authors.forename: J D
authors.initials: JD
authors.lastname: Oldham
authors.forename: N C
authors.initials: NC
authors.lastname: Friggens
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002417:Cattle; D004777:Environment; D005260:Female; D007774:Lactation / Q000378:metabolism*; D008892:Milk / Q000378:metabolism*; D011247:Pregnancy; D013045:Species Specificity; D013997:Time Factors