Background： Main objectives were to determine to what extent Smartamine M（SM） supplementation to a prepartal higher-energy diet could alter neutrophil（PMN） and liver tissue immunometabolic biomarkers, and whether...Background： Main objectives were to determine to what extent Smartamine M（SM） supplementation to a prepartal higher-energy diet could alter neutrophil（PMN） and liver tissue immunometabolic biomarkers, and whether those responses were comparable to those in cows fed a prepartal lower-energy diet（CON）.Results： Twenty-eight multiparous Holstein cows were fed CON（NEL= 1.24 Mcal/kg DM） during d-50 to d-22 relative to calving. From d-21 to calving, cows were randomly assigned to a higher-energy diet（OVE, n = 9; NEL= 1.54 Mcal/kg DM）, OVE plus SM（OVE ＋ SM, n = 10; SM = 0.07 % of DM） or remained on CON（n = 9）. Al cows received the same basal lactation diet（NEL= 1.75 Mcal/kg DM）. Supplementation of SM（OVE ＋ SM） continued until 30 d postpartum. Liver biopsies were harvested at d-10, 7, and 21 relative to parturition. Blood PMN isolated at-10, 3, and 21 d relative to calving was used to evaluate gene expression. As expected, OVE increased liver lipid content postpartum; however,cows fed OVE ＋ SM or CON had lower concentrations than OVE. Compared with OVE, cows in CON and OVE ＋ SM had greater DMI postpartum and milk production. Furthermore, cows fed OVE ＋ SM had the greatest milk protein and fat percentage and lowest milk SCC despite having intermediate PMN phagocytic capacity. Adaptations in PMN gene expression in OVE ＋ SM cows associated with the lower SCC were gradual increases from-10 to 21 d in genes that facilitate migration into inflammatory sites（SELL, ITGAM）, enzymes essential for reducing reactive oxygen metabolites（SOD1, SOD2）, and a transcription factor（s） required for controlling PMN development（RXRA）. The greater expression of TLR4 on d 3, key for activation of innate immunity due to inflammation, in OVE compared with CON cows suggests a more pronounced inflammatory state. Feeding OVE ＋ SM dampened the upregulation of TLR4, despite the fact that these cows had similar expression of the pro-inflammatory genes NFKB1 and TNF as OVE. Cows in CON had lower overall expression of these inflammation-related genes and GSR, which generates reduced glutathione, an important cellular antioxidant.Conclusions： Although CON cows appeared to have a less stressful transition into lactation, SM supplementation was effective in alleviating negative effects of energy-overfeeding. As such, SM was beneficial in terms of production and appeared to boost the response of PMN in a way that improved overall cow health.展开更多
基金in part by Adisseo(Commentry,France)and Hatch funds under project ILLU-538–914National Institute of Food and Agriculture,Washington,DC,USA
文摘Background： Main objectives were to determine to what extent Smartamine M（SM） supplementation to a prepartal higher-energy diet could alter neutrophil（PMN） and liver tissue immunometabolic biomarkers, and whether those responses were comparable to those in cows fed a prepartal lower-energy diet（CON）.Results： Twenty-eight multiparous Holstein cows were fed CON（NEL= 1.24 Mcal/kg DM） during d-50 to d-22 relative to calving. From d-21 to calving, cows were randomly assigned to a higher-energy diet（OVE, n = 9; NEL= 1.54 Mcal/kg DM）, OVE plus SM（OVE ＋ SM, n = 10; SM = 0.07 % of DM） or remained on CON（n = 9）. Al cows received the same basal lactation diet（NEL= 1.75 Mcal/kg DM）. Supplementation of SM（OVE ＋ SM） continued until 30 d postpartum. Liver biopsies were harvested at d-10, 7, and 21 relative to parturition. Blood PMN isolated at-10, 3, and 21 d relative to calving was used to evaluate gene expression. As expected, OVE increased liver lipid content postpartum; however,cows fed OVE ＋ SM or CON had lower concentrations than OVE. Compared with OVE, cows in CON and OVE ＋ SM had greater DMI postpartum and milk production. Furthermore, cows fed OVE ＋ SM had the greatest milk protein and fat percentage and lowest milk SCC despite having intermediate PMN phagocytic capacity. Adaptations in PMN gene expression in OVE ＋ SM cows associated with the lower SCC were gradual increases from-10 to 21 d in genes that facilitate migration into inflammatory sites（SELL, ITGAM）, enzymes essential for reducing reactive oxygen metabolites（SOD1, SOD2）, and a transcription factor（s） required for controlling PMN development（RXRA）. The greater expression of TLR4 on d 3, key for activation of innate immunity due to inflammation, in OVE compared with CON cows suggests a more pronounced inflammatory state. Feeding OVE ＋ SM dampened the upregulation of TLR4, despite the fact that these cows had similar expression of the pro-inflammatory genes NFKB1 and TNF as OVE. Cows in CON had lower overall expression of these inflammation-related genes and GSR, which generates reduced glutathione, an important cellular antioxidant.Conclusions： Although CON cows appeared to have a less stressful transition into lactation, SM supplementation was effective in alleviating negative effects of energy-overfeeding. As such, SM was beneficial in terms of production and appeared to boost the response of PMN in a way that improved overall cow health.
