Symposium review: Modulating adipose tissue lipolysis and remodeling to improve immune function during the transition period and early lactation of dairy cows

Abstract

Despite major advances in our understanding of transition and early lactation cow physiology and the use of advanced dietary, medical, and management tools, at least half of early lactation cows are reported to develop disease and over half of cow deaths occur during the first week of lactation. Excessive lipolysis, usually measured as plasma concentrations of free fatty acids (FFA), is a major risk factor for the development of displaced abomasum, ketosis, fatty liver, and metritis, and may also lead to poor lactation performance. Lipolysis triggers adipose tissue (AT) remodeling that is characterized by enhanced humoral and cell-mediated inflammatory responses and changes in its distribution of cellular populations and extracellular matrix composition. Uncontrolled AT inflammation could perpetuate lipolysis, as we have observed in cows with displaced abomasum, especially in those animals with genetic predisposition for excessive lipolysis responses. Efficient transition cow management ensures a moderate rate of lipolysis that is rapidly reduced as lactation progresses. Limiting FFA release from AT benefits immune function as several FFA are known to promote dysregulation of inflammation. Adequate formulation of pre- and postpartum diet reduces the intensity of AT lipolysis. Additionally, supplementation with niacin, monensin, and rumen-protected methyl donors (choline and methionine) during the transition period is reported to minimize FFA release into systemic circulation. Targeted supplementation of energy sources during early lactation improves energy balance and increases insulin concentration, which limits AT lipolytic responses. This review elaborates on the mechanisms by which uncontrolled lipolysis triggers inflammatory disorders. Details on current nutritional and pharmacological interventions that aid the modulation of FFA release from AT and their effect on immune function are provided. Understanding the inherent characteristics of AT biology in transition and early lactation cows will reduce disease incidence and improve lactation performance.

Prediction of metabolic clusters in early-lactation dairy cows using models based on milk biomarkers

“…A certain level of FFA is considered normal and necessary. However, FFA concentrations increase when lipolysis is excessive; this is associated with a detrimental effect on immunity, metabolism, and milk production (Roche et al, 2013;Contreras et al, 2018). Part of the circulating FFA are converted into ketone Clusters were created using the k-means clustering method based on the log-transformed and standardized concentrations of glucose, IGF-I, FFA, and BHB.…”

Influence of adipocyte size and adipose depot on the number of adipose tissue macrophages and the expression of adipokines in dairy cows at the end of pregnancy

“…An additional factor that might confound the results of the present study is the fact that mRNA expression was determined at the level of the adipose tissue. This comprises the mRNA expression of all the cells that reside within the adipose tissue, including preadipocytes, fibroblasts, endothelial cells, mast cells, dendritic cells, neutrophils, eosinophils, basophils, lymphocytes, and macrophages (Heilbronn and Campbell, 2008;Contreras et al, 2018). Based on the results of the present study, it is not possible to identify the cellular source of the different adipokines.…”

Symposium review: Selection for fertility in the modern dairy cow—Current status and future direction for genetic selection

“…Postpartum uterine disease has long-term effects on the subsequent establishment of pregnancy (Carneiro et al, 2016;Ribeiro et al, 2016). The inability of the cow to resolve uterine disease may be explained in part by immune dysfunction early postpartum that is caused by a metabolic profile that antagonizes the innate immune system (Contreras et al, 2018;Sheldon et al, 2018).…”

“…The cow's immune system is primarily responsible for resolution of disease and recovery from inflammation within the uterus postpartum (Contreras et al, 2018;Sheldon et al, 2018). The low circulating glucose and elevated circulating BHB that are found during early lactation can antagonize circulating immune cell function (Lucy et al, 2014).…”