Effects of Scutellaria baicalensis extract on inflammatory biomarkers and performance in transition dairy cows

Heightened and persistent inflammation during the periparturient period impedes health and performance in early lactation. Identifying mitigation strategies capable of attenuating inflammatory cascades without interfering with the inflammation necessary to support normal physiological processes is of significant interest. Dietary supplementation of Scutellaria baicalensis extract (SBE; Dairy Relieve, Elanco Animal Health, Greenfield, IN) has been shown to improve milk performance, an effect hypothesized to be mediated by its anti-inflammatory and antioxidant properties. Thus, study objectives were to evaluate the effect of SBE supplementation on performance and inflammation in primiparous and multiparous cows and to determine the optimal feeding duration. Holstein cows (n = 404; 80 primiparous and 324 multiparous) were used in a randomized complete block design and randomly assigned within block (parity and expected calving date) to 1 of 4 dietary treatments: (1) control diet (CON), (2) 10 g/d of SBE from 255 ± 3 d carried calf (DCC) to 21 DIM (SBE42), (3) 10 g/d SBE from 255 ± 3 DCC to 90 DIM (SBE111), and (4) 10 g/d SBE from 1 to 90 DIM (SBE90). Cows were housed in a freestall barn and received the same base ration. Dietary treatments were administered individually by restraining cows in headlocks for a minimum of 10 min/d during which the top-dress pellet (113.5 g/d) containing 10 g of SBE was administered. Cows were milked 3 times daily for the first 6 wk of lactation and twice daily for the remainder of the data collection period (i.e., 40 wk). Milk yield was recorded from wk 1 to 40, and milk samples for composition analysis were obtained every 2 wk from wk 1 to 15 relative to calving. Blood samples were obtained via coccygeal venipuncture at 7, 21, and 90 DIM from a random subset of cows (24 cows/treatment). Data were analyzed using mixed effects repeated measures ANOVA. A preplanned contrast was used to estimate differences in CON versus cows supplemented with SBE to 90 DIM (SBE111 + SBE90). Over the 40-wk lactation, milk yield increased 1.5 kg/d in SBE111 relative to CON cows. Milk yield was similar in SBE42 and CON cows. Feeding SBE to 90 DIM (SBE111 and SBE90) tended to increase energy-corrected milk yield and milk fat and protein yields, whereas it tended to decrease MUN over the first 15 weeks of lactation relative to CON. Regardless of prepartum feeding, SBE supplementation to 90 DIM tended to increase circulating sirtuin-1 concentrations. Relative to CON, circulating α-1-acid glycoprotein (AGP) increased in SBE-fed cows at 7 DIM, whereas concentrations decreased at 21 DIM. In summary, the optimal feeding window of SBE for improving postpartum performance for cows enrolled in the current study was from 255 DCC to 90 DIM. Changes in circulating sirtuin-1 and AGP concentrations with SBE supplementation support the hypothesis that improved performance with SBE supplementation is partially mediated by the anti-inflammatory properties of SBE.