Effect of chromium on bioenergetics and leukocyte dynamics following immunoactivation in lactating Holstein cows

Abstract

Activated immune cells are insulin sensitive and utilize copious amounts of glucose. Because chromium (Cr) increases insulin sensitivity and may be immunomodulatory, our objective was to evaluate the effect of supplemental Cr (KemTrace Cr propionate, 20 g/d; Kemin Industries Inc., Des Moines, IA) on immune system glucose utilization and immune system dynamics following an intravenous endotoxin challenge in lactating Holstein cows. Twenty cows (320 ± 18 d in milk) were randomly assigned to 1 of 4 treatments: (1) pair-fed (PF) control (PF-CON; 5 mL of saline; n = 5), (2) PF and Cr supplemented (PF-Cr; 5 mL of saline; n = 5), (3) lipopolysaccharide (LPS)-euglycemic clamp and control supplemented (LPS-CON; 0.375 µg/kg of body weight LPS; n = 5), and (4) LPS-euglycemic clamp and Cr supplemented (LPS-Cr; 0.375 µg/kg of body weight LPS; n = 5). The experiment was conducted serially in 3 periods (P). During P1 (3 d), cows received their respective dietary treatments and baseline values were obtained. At the initiation of P2 (2 d), either a 12-h LPS-euglycemic clamp was conducted or cows were PF to their respective dietary counterparts. During P3 (3 d), cows consumed feed ad libitum and continued to receive their respective dietary treatment. During P2, LPS administration decreased dry matter intake (DMI; 40%) similarly among diets, and by experimental design the pattern and magnitude of reduced DMI were similar in the PF cohorts. During P3, LPS-Cr cows tended to have decreased DMI (6%) relative to LPS-CON cows. Relative to controls, milk yield from LPS-challenged cows decreased (58%) during P2 and LPS-Cr cows produced less (16%) milk than LPS-CON cows. During P3, milk yield progressively increased similarly in LPS-administered cows, but overall milk yield remained decreased (24%) compared with PF controls. There were no dietary treatment differences in milk yield during P3. Circulating insulin increased 9- and 15-fold in LPS-administered cows at 6 and 12 h postbolus, respectively, compared with PF controls. Compared with LPS-CON cows, circulating insulin in LPS-Cr cows was decreased (48%) at 6 h postbolus. Relative to PF cows, circulating LPS binding protein and serum amyloid A from LPS-administered cows increased 2- and 5-fold, respectively. Compared with PF cows, blood neutrophil counts in LPS-infused cows initially decreased, then gradually increased 163%. Between 18 and 48 h postbolus, the number of neutrophils was increased (12%) in LPS-Cr versus LPS-CON cows. The 12-h total glucose deficit was 220 and 1,777 g for the PF and LPS treatments, respectively, but glucose utilization following immune activation was not influenced by Cr. In summary, supplemental Cr reduced the insulin response and increased circulating neutrophils following an LPS challenge but did not appear to alter the immune system's glucose requirement following acute and intense activation.

Impacts of chronic and increasing lipopolysaccharide exposure on production and reproductive parameters in lactating Holstein dairy cows

“…In agreement with previous reports (Waldron et al, 2006;Moyes et al, 2014;Horst et al, 2018), LPS infusion initially decreased DMI and the pattern was similar in CON-PF cows by experimental design. In contrast to expectations, milk yield did not differ between treatments but remained depressed during the infusion period, and this is mostly explained by decreased DMI, which did not return to baseline until d 6.…”

“…In contrast to expectations, milk yield did not differ between treatments but remained depressed during the infusion period, and this is mostly explained by decreased DMI, which did not return to baseline until d 6. In our LPS bolus experiments, the pair-fed controls produce substantially more milk than immunoactivated cows (Kvidera et al, 2017;Horst et al, 2018). In LPS-AL cows, overall milk fat content and MUN was increased.…”

“…Local leukocyte stimulation and release of inflammatory mediators stimulate further immune cell proliferation and recruitment to the infection site (Lang et al, 1992). In bolus LPS studies, a biphasic response is typically observed with initial leukopenia and subsequent leukocytosis (Kvidera et al, 2017;Horst et al, 2018). Herein circulating monocytes exhibited a similar pattern, whereas neutrophil and lymphocyte count dynamics were opposite.…”

“…The LPS dose was increased every day ( Figure 1A) and calculated based on BW obtained during the acclimation period. The LPS stock solution (Escherichia coli O55:B5, L2880, Sigma Aldrich, St. Louis, MO) was prepared at a concentration of 300 μg/mL, passed 3571 through a 0.2-μm sterile syringe filter (Thermo Fisher Scientific, Waltham, MA), and stored in a sterile glass bottle 24 h before P2 as we have previously described (Kvidera et al, 2017;Horst et al, 2018). The LPS dose and increasing daily infusion rate were selected based on data from a similar experimental design utilizing pigs (Bidne et al, 2018b;Huntley et al, 2018).…”

Effects of dietary zinc source on the metabolic and immunological response to lipopolysaccharide in lactating Holstein dairy cows

“…Mounting a successful immune response is dependent on effective leukocyte communication (cytokine and chemokine production), extravasation, cellular function (i.e., intracellular killing, reactive oxygen species production, cytokine production), and the elimination of cell debris and harmful byproducts. The energetic costs of initiating an immune response are substantial (Johnson, 2012), and this is particularly true for glucose (Kvidera et al, 2016(Kvidera et al, , 2017aHorst et al, 2018). Therefore, dietary strategies capable of improving barrier integrity and immune responses are Effects of dietary zinc source on the metabolic and immunological response to lipopolysaccharide in lactating Holstein dairy cows of practical and economic interest, particularly in lactating dairy cows because glucose is critical for copious milk synthesis (Baumgard et al, 2017).…”