PSI-18 Adiponectin serum concentrations in late pregnancy and early lactation in primiparous and multiparous Holstein dairy cows.

摘要

The peripartal decrease of insulin sensitivity in peripheral tissues other than the mammary gland facilitates draining of glucose towards the mammary gland at that time. Adiponectin is an insulin-sensitizing adipokine; its concentrations decrease around parturition in dairy cows. Based on the different metabolic stress in primiparous (PP) and multiparous (MP) cows (PP are still growing, MP have more milk), we hypothesized that the serum concentrations of adiponectin in the dry period and subsequent lactation will be greater in PP than in MP cows. Blood was sampled -50, -14, 8, 28, and 100 days relative to calving from 201 PP and 456 MP Holstein cows on three experimental farms, i.e. a subset from the optiKuh project*. Individual feed intake and milk yield were recorded daily, milk composition was analyzed weekly, and energy balance (EB) was calculated on a weekly basis assuming 10% of bodyweight at calving as body gain for PP. Serum adiponectin concentrations were measured with an in-house developed bovine-specific ELISA. For statistical analyses the linear mixed model was used (SPSS 25; fixed effects: time, parity, farm, all interactions; random effects: cow). Due to a significant time*parity interaction for adiponectin, further analyses were performed separately for the pre- and postpartum period. Results are presented as means ±SEM. Prepartum, PP had lower adiponectin concentrations (23.3 ± 0.37 µg/mL) and EB (10.6 ± 1.29 MJ NEL/day) than MP (Adiponectin: 26.7 ± 0.26 µg/mL; p<0.001; EB: 16.9 ± 1.41 MJ NEL/day; p=0.014). Postpartum, PP had higher adiponectin concentrations (26 ± 0.25µg/mL) than MP (24.4 ± 0.18 µg/mL; p=0.002) but EB did not differ (p=0.2) although MP yielded more milk (39.1 ± 0.28 kg/day) than PP (29.2 ± 0.29 kg/day; p<0.001). The higher adiponectin concentrations and assumingly greater insulin sensitivity postpartum in PP would allow for further body growth beside lactation. *funded by the German Federal Ministry of Food and Agriculture.