The association of Curcuma and Scutellaria plant extracts improves laying hen thermal tolerance and egg oxidative stability and quality under heat stress conditions

Abstract

Chronic exposure to high ambient temperatures is detrimental to laying hen performance and egg quality. Plant secondary metabolites may alleviate effects, partly due to their antioxidant activities. Herein, we investigated the effects of dietary supplementation with a phytonutrient solution (PHYTO) consisting of a plant extract combination of Scutellaria baicalensis and Curcuma longa on young layers (25–32 wk of age) raised under naturally elevated temperature conditions. Four hundred, 24-wk-old Lohmann hens were allocated in 50 cages and, after a week of adaptation, were offered a diet either containing 2 g/kg of PHYTO or not, for 8 wk. Hen BW was measured at the beginning and end of the trial, and egg production and feed intake were recorded weekly. At week 32, four eggs per cage were collected to determine egg quality characteristics as well as the rate of lipid and albumen oxidation in fresh eggs. At the end of the trial, two hens per cage were blood sampled for assessment of biochemical markers, one of which was euthanized for histopathological evaluation of the liver and intestine and assessment of intestinal histomorphometry. The herbal mixture supplementation significantly increased egg production rate at weeks 28 and 29 and for the overall production period, and feed efficiency at weeks 26–29. In addition, the degree of liver necrosis and microvascular thrombosis was lower (P < 0.05) whereas intestinal villosity was greater in duodenal and jejunal segments (P < 0.05) in the PHYTO compared to the control group. Supplementation also reduced (P < 0.05) blood concentrations of corticosterone, alanine aminotransferase activity, and TBARS, and a reduction in catalase activity was observed. Egg quality characteristics were not affected, except for eggshell thickness, egg diameter, and eggshell breaking strength that were superior in the PHYTO group (P < 0.05). PHYTO supplementation significantly improved egg lipid oxidation status of fresh eggs. In conclusion, supplementation with PHYTO improved laying hen productivity and egg quality, which was associated with an improvement in laying hen thermotolerance.

Effects of Dietary Supplementation of Essential Oils, Lysozyme, and Vitamins’ Blend on Layer Hen Performance, Viral Vaccinal Response, and Egg Quality Characteristics

“…Additionally, water supplementation with the L + EO + VIT blend led to decreased TBARS serum concentration in birds, indicating improved endogenous antioxidant capacity. These results are in accordance with previous reports supporting the effect of phytobiotics as antioxidants [43].…”

“…According to our results, the performance of IBV and NDV vaccination οn a flock of young laying hens had a positive effect on egg production three weeks after administration; although for a short timeframe vaccination stress led to a minor decrease in the production rate. A positive effect of phytobiotics has also been reported on egg production [ 42 , 43 ]. While a few studies have reported positive effects of certain EOs on egg production, others have found no significant impact [ 36 ].…”

The impact of curcumin on livestock and poultry animal's performance and management of insect pests

“…The addition of curcumin to broiler diets significantly improved the levels of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) in breast and thigh muscles (101). Similarly, a recent study showed that egg production in broilers benefited from improved oxidative stability and egg shell breaking force when a phytonutrient solution of Curcuma was supplemented in laying hens (102). Curcumin supplementation in duck feed improved the meat quality by limiting the extent of lipid oxidation during the post-mortem period (103).…”

Dietary Chinese herbal mixture supplementation improves production performance by regulating reproductive hormones, antioxidant capacity, immunity, and intestinal health of broiler breeders

“…Recent research also demonstrates that herbs in the diet can increase egg production and egg quality in laying hens ( Yu et al, 2023 ). Besides, in poultry production, Chinese herbal, including compound formulas, extracts, and active compounds of herbs, are reported to have effective antioxidant activity and can regulate immunity and gut microbiota, improving the function of the intestinal barrier ( Ding et al, 2022 ; Giannenas et al, 2022 ). The beneficial effects of Chinese herbals are largely accomplished through the regulation of the gut microbiota, which plays a vital role in maintaining gut health and influencing the overall production performance of laying hens ( An et al, 2019 ; Wang et al, 2020 ).…”