Impacts of varying methionine to cysteine supplementation ratios on growth performance, oxidative status, intestinal health, and gene expression of immune response and methionine metabolism in broilers under Eimeria spp. challenge

Coccidiosis in Egg-Laying Hens and Potential Nutritional Strategies to Modulate Performance, Gut Health, and Immune Response

“…The negative effect of coccidiosis on the parameters associated with gastrointestinal health, such as increased intestinal lesion scores, gastrointestinal permeability, a breach in tight junction integrity, damage to intestinal morphology, inflammation, and oxidative stress, are related to Eimeria multiplication and release in the gut lumen [2,[5][6][7]31]. Continuous intestinal epithelial cell turnover occurs throughout the lifetime of the chickens.…”

“…During Eimeria infection, although oxidative defense mechanisms are active, the production of ROS exceeds the production of enzymes suppressing ROS, aggravating the situation. Previous studies have reported that Eimeria infection increased the markers associated with oxidative stress, such as reduced concentration of total antioxidant capacity (TAC) from 15 to 40% [31,46] and reduced GPx and GSH activity [31,47]. Furthermore, Eimeria infection also increased the markers of radical-induced damage, such as superoxide dismutase (SOD) and malondialdehyde (MDA) [34][35][36]44,48,49].…”

“…A study by Lai et al (2018Lai et al ( , 2023 [148,149] reported that supplementing extra methionine above the requirement in vaccinated birds did not have any beneficial effect on the performance, immune response, or oxidative status of Partridge shank broilers. However, reducing the level of methionine in the diets during Eimeria infection significantly affects the performance, oxidative status, and immune responses in challenged broilers [31,47,150,151], and supplementing 0.75% methionine in low-crude protein diets increased the detrimental effect of Eimeria infection on broiler health and performance [6]. In laying hens under heat stress, similar results were observed as those for Eimeria-challenged broilers, where reducing the methionine level reduced the production performance and bone mineralization and increased the oxidative stress of laying hens [152].…”

Effects of Methionine Supplementation Levels in Normal or Reduced Protein Diets on the Body Composition and Femur Bone Characteristics of Broilers Challenged with Coccidia

“…This transition underscores the imperative to explore alternative strategies to mitigate the impact of coccidiosis. In addition to investigating the effects of feed additives, such as probiotics, prebiotics, and phytogenic compound supplementations [ 10 ], exploring the optimal nutrient requirements for birds under challenged conditions is also vital to improve the health and performance of these animals [ 11 , 12 , 13 , 14 ].…”

Effects of methionine supplementation in a reduced protein diet on growth performance, oxidative status, intestinal health, oocyst shedding, and methionine and folate metabolism in broilers under Eimeria challenge

“…Methionine (Met) as one of the essential amino acids is also considered the first limiting amino acid in poultry production [ 14 , 15 ]. It not only plays a crucial role in maintaining bird growth and protein synthesis, but also holds significant importance in supporting the intestinal health, immune responses, and anti-oxidative functions of the birds [ 16 – 21 ]. Besides the established significance in protein synthesis, Met also plays a crucial role in regulating several signaling pathways, including the mTOR and Wnt/β-catenin pathways [ 22 , 23 ].…”