Altering the ratio of dietary palmitic and oleic acids affects nutrient digestibility, metabolism, and energy balance during the immediate postpartum in dairy cows

This article is the second from an experiment that determined effects of altering dietary ratio palmitic (C16:0) and oleic (cis-9 C18:1) acids on digestibility, production, metabolic responses dairy cows during immediate postpartum. elaborates effect these diets nutrient energy balance, metabolism. Fifty-six multiparous were used in a randomized complete block design randomly assigned to 1 4 treatments fed 24 d milk. The were: (1) control (CON) diet not supplemented with fatty (FA); (2) FA blend containing 80% C16:0 10% cis-9 C18:1 (80:10); (3) 70% 20% (70:20); (4) 60% 30% (60:30). supplement blends added at 1.5% dry matter by replacing soyhulls CON diet. Three preplanned contrasts compare treatment differences: versus FA-supplemented diets, (80:10 + 70:20 60:30)/3; linear inclusion diets; quadratic diets. increased digestibility matter, neutral detergent fiber, 18-carbon FA, total compared CON. We observed tendency for interaction between time because difference 60:30 tended increase over time. Increasing linearly 16-carbon, 18-carbon, FA. Interestingly, absorbed was positively related milk, milk fat yield, energy-corrected plasma insulin, albumin, negatively nonesterified (NEFA) body weight loss. intake digestible energy, metabolizable net lactation Compared CON, output negative balance. lactation. Although increasing did affect maintenance, improved but we observe differences NEFA albumin. decreased insulin ?-hydroxybutyrate. During carryover period, no blood metabolites observed. Our results indicate feeding supplements postpartum period intake, non-fat-supplemented reduced markers mobilization, balance