Dietary supplementation with sodium humate improves egg quality and immune function of laying hens

Abstract

The aim of this study was to evaluate the influence of the dietary addition of sodium humate (HAS) on performance and immune response of laying hens during peak lay, over an eight-week period. Laying hens, aged 24 weeks old, were randomly allotted to four dietary treatments: a basal control diet or the basal diet supplemented with 0.1, 0.3 or 0.5% HAS. Each treatment had six replicates with 15 layers per replicate. Egg production, egg quality, serum antioxidant parameters and immunity indexes were measured. HAS had no significant effect on egg production or egg and shell quality, but all supplemental levels significantly improved Haugh unit values and egg yolk colour. Supplementation with all levels of HAS significantly increased serum immunoglobuline (Ig) level compared to the hens fed the control diet. Feeding either 0.1 or 0.5% HAS significantly increased serum IgM levels. The results indicated that dietary supplementation with HAS can enhance egg albumin quality and improve immunity in laying hens.

Effects of Dietary Supplementation of Humic Substances on Production Parameters, Immune Status and Gut Microbiota of Laying Hens

“…Dietary supplementation with HS additives had a significant effect on the laying rate, daily egg mass, egg weight, and feed conversion, which indicate the ability of HS to stabilize the intestinal microbiota, thus ensuring improved nutrient utilization in feed [38,39]. These findings are consistent with our results.…”

“…The increased percentage of the IgM+ lymphocyte subpopulation is consistent with the finding of increased gene expression for IgA in the gut. Zhang et al [38] (2020) also noted significantly elevated serum IgM as well as IgG levels after the administration of 0.1 and 0.5% HS to laying hens, which confirms the activation of B cells. Similarly, Salah et al [53] reported an increase in the serum gamma globulin fraction containing most of immunoglobulins after 5 days of humic acid application to broiler chickens.…”

Mechanisms of Action of Humic Substances as Growth Promoters in Animals

“…For example, elevated lymphoid tissue distribution and density in the bursa of Fabricius and thyme [25] increased concentration of antibodies against infectious bursal disease [69], avian influenza [70], and Newcastle disease virus (NDV) [71,72], and greater lymphocytes and leukocytes counts, globulins (α, β, and γ), phagocytosis, and phagocytic index have been found in HS-added broilers [73]. In laying hens, supplementation HS significantly increased the serum IgG and IgM level [74].…”

“…In laying hens and partridges supplemented with HS, benefits in feed intake, egg production, egg weight, and feed conversion ratio have been observed [118-120, 130, 147]. Improved Haugh unit values and egg yolk color in HS-added laying hens [74] and increased albumen height, albumen index, and Haugh units of the egg in partridge [148] were observed. A strong tendency of lower mortality have been reported in HS-added broilers [25, 67,77] and Japanese quails [27].…”

Ameliorative impacts of sodium humate on heat‐stressed laying Japanese quail (Coturnix coturnix Japonica)

“…Humates (humic substances) are the salt forms of humic acid that originated from microbial decomposition of decayed plant substances, with Na+, K+, Ca 2 +, Fe 2 + and Al 3 + as exchange sites instead of hydrogen (Zhang et al, 2020). Humates is a bioactive compound that consists of humic acid, humus, fulvic acid, ulmic acid and other microelements that exhibit potent anti‐inflammatory, antioxidant, antitoxic, antiviral and immunostimulatory (Arafat et al, 2015; Vaskova et al, 2018).…”