Glucose metabolism and the somatotropic axis in dairy cows after abomasal infusion of essential fatty acids together with conjugated linoleic acid during late gestation and early lactation

Sufficient glucose availability is crucial for exploiting the genetic potential of milk production during early lactation, and endocrine changes are mainly related to repartitioning nutrient supplies toward mammary gland. Long-chain fatty acids, such as essential acids (EFA) conjugated linoleic acid (CLA), have improve negative energy balance modify changes. In present study, hypothesis that combined CLA EFA treatment supports metabolism around time calving stimulates insulin action somatotropic axis in cows an additive manner was tested. Rumen-cannulated German Holstein (n = 40) were investigated from wk 9 antepartum (AP) until postpartum (PP). The abomasally supplemented with coconut oil (CTRL, 76 g/d); 78 g/d linseed 4 safflower (EFA); Lutalin (CLA, isomers cis-9,trans-11 trans-10,cis-12 CLA, each 10 or combination EFA+CLA. Blood samples collected several times AP PP determine concentrations plasma metabolites hormones axis. Liver tissue days measure glycogen concentration mRNA abundance genes gluconeogenesis On d 28 21 PP, endogenous (eGP) oxidation (GOx) measured via tracer technique. higher than non-CLA-treated cows, β-hydroxybutyrate non-EFA on PP. eGP increased elevated decreased CLA-treated cows; GOx lower CTRL after all groups non-CLA at points. Plasma glucagon cortisol groups. glucagon/insulin glucose/insulin ratios group transition period. IGF-I 42 dry period lactation cows. IGF binding protein (IGFBP)-3/-2 ratio blood Hepatic higher, but PC IGFBP2 1 IGFBP3 PCK1, PCK2, G6PC, PCCA, HMGCS2, IGFBP2, INSR points Results indicated along stimulation treated whereas stimulated not systemic effects EFA+CLA very similar those treatment, hepatic gene expression partially corresponded treatment.