Effects of 5-aminolevulinic acid supplementation on milk production, iron status, and immune response of dairy cows

Abstract

The objective of this study was to investigate the effect of 5-aminolevulinic acid (5-ALA) as a dietary supplement on milk yield and composition as well as iron status and immune response in lactating dairy cows. In this study 13 lactating Holstein cows were randomly assigned to either a control group or a treatment group supplemented with 10 mg of 5-ALA per kilogram of dry matter. During feeding, 5-ALA was mixed with a small amount of the total mixed ration and top-dressed. The experiments followed a crossover design with 2 periods. Each period consisted of an adaptation period of 12 d and a test period of 2 d. Dairy cows fed the diet supplemented with 5-ALA exhibited increased counts of white blood cells and granulocytes compared with the control group. The rate of phagocytosis and mitogen-induced proliferation of peripheral blood mononuclear cells in cows fed 5-ALA were higher than in cows fed a basal diet. However, 5-ALA did not affect iron status or plasma biochemical composition. Supplementation with 5-ALA improved milk protein and milk casein contents; however, it had no effect on milk production, milk fat, lactose, total solids, or solids-not-fat, compared with the control. We conclude that dietary supplementation of 5-ALA to lactating dairy cows may have a positive effect on milk protein synthesis and the immune response.

Effects of 5-Aminolevulinic Acid as a Supplement on Animal Performance, Iron Status, and Immune Response in Farm Animals: A Review

“…Moreover, seven studies assessed production performance. Four studies examined milk composition, e.g., milk fat, milk protein, milk casein, milk glucose, milk lactose, total solid, and Fe concentration [ 14 , 22 , 23 , 28 ]. Egg production and quality were also assessed in three studies: egg weight, shell breaking strength, shell thickness, Haugh unit, yolk color unit, yolk index, shells color, albumin height, and Fe concentration in yolk [ 19 , 20 , 21 ].…”

“…In this review, we considered indices reflecting different levels of defense mechanisms of the immune system: white blood cell (WBC) count, differential count, and cell-mediated immunity, which involves soluble proteins and bioactive small molecules released by the activated cells, such as cytokines, as well as the membrane-bound receptors and cytoplasmic proteins that bind to molecular patterns expressed on the surfaces of invading pathogens. Hence, the immune response in the evaluated studies was addressed through an estimation of WBC count and lymphocyte count, as well as measurement of tumor necrosis factor (TNF)-α; insulin-like growth factor (IGF)-1; haptoglobin; plasma cortisol [ 8 ]; cluster of differentiation antigen positive cells 2, 4, and 8 (CD2+, CD4+, CD8+, respectively); the ratio of CD4+ to CD8+ cells; B-cells; major histocompatibility complex classes I and II [ 17 ]; rates of phagocytosis in blood mononuclear cells (MNC); mitogen concanavalin A and phytohemagglutinin-induced proliferation of blood MNC [ 16 , 22 ]; levels of cluster of differentiation 3 (CD3) mRNA in the spleen; plasma thiobarbituric acid reactive substances (TBARS); plasma ceruloplasmin concentration; expression of interferon-γ; inducible nitric oxide synthase (iNOS); interleukin (IL)-6 and TNF-like ligand 1A mRNA; levels of IL-2; toll-like receptor 2, 4, and 7 mRNA in the spleen during Escherichia coli lipopolysaccharide (LPS) stimulation; ceruloplasmin oxidase [ 16 ]; differential count of WBC [ 13 ]; immunoglobin G (IgG) [ 8 , 14 , 29 ]; and the weight of immune organs, such as spleen, bursa of Fabricius, liver, and the thymus [ 15 , 16 , 31 ]. Readers are encouraged to refer to Supplementary Table S1 for further details.…”

“…Concerning production performance, 5-ALA supplementation improved milk protein [ 14 , 22 , 23 ], milk fat [ 14 ], milk casein [ 22 ], and Fe concentration in milk [ 28 ], while milk glucose, milk lactose, and total solids were unaffected. Similarly, 5-ALA supplementation improved egg production [ 20 , 21 ] and quality, such as egg weight [ 21 ], Haugh unit [ 19 , 20 , 21 ], yolk color unit [ 20 , 21 ], eggshell color, Fe concentration in yolk [ 20 ], and egg yolk index [ 19 ].…”

“…Supplementation of 5-ALA was associated with improved IGF-1 (2 h) and WBCs (12 h) post-challenge by LPS [ 8 ]. Also, 5-ALA increased levels of CD2+, CD8+, B-cells, major histocompatibility complex classes I and II [ 17 ], the rate of phagocytosis and mitogen-induced proliferation of peripheral MNC [ 16 , 22 ], CD3 mRNA in the spleen, and plasma TBARS [ 16 ]. On the other hand, dietary use of 5-ALA reduced plasma cortisol and TNF-α concentration at 2 h post-challenge by LPS [ 8 ].…”

“…Furthermore, the literature documents an array of 5-ALA uses in the medical field, especially for tumor diagnosis and cancer treatment [ 11 , 12 ]. Similarly, 5-ALA has been introduced to farm animals as a dietary supplement to improve blood iron status [ 13 , 14 , 15 ], enhance immunity, increase resistance to disease [ 8 , 16 , 17 ], improve growth [ 18 ], and enhance egg production and quality [ 19 , 20 , 21 ], as well as milk composition [ 14 , 22 , 23 ]. However, available studies report mixed findings.…”