Dietary cinnamaldehyde with carvacrol or thymol improves the egg quality and intestinal health independent of gut microbiota in post-peak laying hens

Abstract

Essential oils have been proven to exert multiple effects on growth performance, production quality, and health status in poultry nutrition, which is dependent on the component and/or dose of essential oils. Diets with the optimal combination of essential oils might be able to improve the performance traits and welfare of laying hens. Therefore, this study was conducted to evaluate the effects of dietary essential oils, which are composed of cinnamaldehyde with carvacrol or thymol, on performance, egg quality, and intestinal health in post-peak laying hens. A total of 384, 50-week-old Hy-line brown laying hens were randomly divided into three groups with 8 replicates of 16 birds each: (1) a basal diet (Ctrl), (2) a basal diet with 100 mg/kg of essential oils consisting of 4.5% cinnamaldehyde with 13.5% carvacrol (CAR+CIN), and (3) a basal diet containing 100 mg/kg of essential oils composed of 4.5% cinnamaldehyde with 13.5% thymol (THY+CIN). The CAR+CIN diet increased the feed consumption from 52 to 55 weeks more than the Ctrl and the THY+CIN diet. Compared with the Ctrl group, the addition of essential oils decreased the dirty egg rate (P = 0.07) in the whole trial period. Regarding egg quality, the birds that received the CAR+CIN and THY+CIN diets increased the eggshell strength (P = 0.099) or Haugh unit (HU, p = 0.03) at 54 weeks, respectively. Supplementation of both CAR+CIN and THY+CIN diets significantly increased the ratio of villus height to crypt depth in the duodenum through increasing villus height and decreasing crypt depth as well as upregulated the mRNA abundances of duodenal occluding and cadherin (P < 0.05). However, the treatment with dietary essential oils did not notably change the proportion of cecal microbiota and bacterial diversity. This study suggested that dietary supplementation of cinnamaldehyde with carvacrol or thymol, the active components of essential oils, could promote egg quality in post-peak laying hens, which might be associated with improved intestinal development and barrier.

Effects of a mixture of glycerol monolaurate and cinnamaldehyde supplementation on laying performance, egg quality, and antioxidant status in laying hens

“…27 Dietary supplementation with cinnamaldehyde, thymol, or carvacrol had no significant effect on the number of pre-grade yellow and white follicles of 50-week-old Hyline brown laying hens. 12 In order to investigate the effect of GCM addition on follicle development in laying hens, the isolation and counting of LWF, SYF, and LYF were conducted by measuring follicle diameter after slaughter. The results showed that the addition of 500 mg kg −1 GCM significantly increased the amount of LWF, and the addition of 1000 mg kg −1 GCM significantly decreased the amount of LYF and tended to increase the amount of LWF.…”

“…Yolk color is formed when fat‐soluble pigments are deposited in the yolk during egg formation, which is one of the important indexes in measuring egg quality and one of the factors affecting the performance of poultry egg products 21 . Many studies have shown that a single GML and plant essential oil mixture containing cinnamaldehyde or thymol shows improved effects on egg quality 7,12,20,22,23 . Wang et al 12 .…”

“…10,11 Dietary supplementation with cinnamaldehyde and carvacrol or thymol can improve the egg quality of laying hens after the peak laying period, which may be related to improving intestinal development and barrier. 12 At present, there are no studies on the combined application of GML and cinnamaldehyde in laying hens during the early laying period.…”

“…Cinnamaldehyde is one of the main components of cinnamon, which is found in cinnamon essential oil and contains a variety of biological properties such as anti‐inflammatory, antibacterial, and antioxidant 10,11 . Dietary supplementation with cinnamaldehyde and carvacrol or thymol can improve the egg quality of laying hens after the peak laying period, which may be related to improving intestinal development and barrier 12 . At present, there are no studies on the combined application of GML and cinnamaldehyde in laying hens during the early laying period.…”

Dietary supplementation with Clostridium butyricum and its ferment substance improves the egg quality and ovarian function in laying hens from 50 to 58 weeks of age

“…The decrease in egg quality of laying hens as extending the egg production period has been noticed in practice (Tumová & Gous, 2012), which is closely linked to sustainedly damaged intestinal barriers and reproductive organs because of age and the high intensity of production (Braw‐Tal et al, 2004; Gu et al, 2021; Wang et al, 2020). To mitigate these adverse effects, some strategies, including organic acids butyrate (Abbasi Arabshahi et al, 2021; Kazempour & Jahanian, 2017; Zhang, Zhang, et al, 2022), vitamins (Gan et al, 2020), probiotics such as Clostridium butyricum ( C. butyricum ) (Wang et al, 2021), and essential oils (Wang et al, 2022; Zhang, Wang, et al, 2022), have been widely sought out in the laying chicken industry. Of note, C. butyricum , a butyrate‐producing bacteria, has been used as a probiotic in clinical and veterinary medicine for decades (Ariyoshi et al, 2022).…”