Impact of L-citrulline on meat production and quality: A study on its effects on meat attributes and nutritional composition.

Abstract

Amino acids are fundamental in sustaining physiological homeostasis during stress conditions. l-citrulline (l-Cit), a non-essential amino acid (NEAA) and metabolic precursor of arginine, has been reported to exert beneficial effects on the health and performance of broiler chickens. This study aimed to investigate the effects of dietary supplementation with varying inclusion levels of l-Cit on growth performance, meat quality, plasma biochemical indices, and thermoregulatory responses in broiler chickens. A total of 120 one-day-old chickens of the Lohman meat (Indian River) strain were randomly allocated to four dietary treatments, and each treatment included 30 birds in 3 replicates each. A 7-day feeding trial was conducted, beginning at 21 days of age. The control group (T0) was fed only a basal diet, while l-Cit was administered through the drinking water at concentrations of 0.5 % (T1), 0.75 % (T2), and 1.0 % (T3) to the respective treatment groups, in addition to the basal diet. Dietary inclusion of l-Cit significantly affected broiler performance and physiology. The T2 group demonstrated the highest body weight gain and lowest feed conversion ratio (FCR) compared with T0, T1, and T3 (p < 0.05). Organ development was increased in T2, with significant increases in bursa, heart, and liver indices, alongside reduced abdominal fat (p < 0.05). Meat quality improved through reduced drip loss and elevated muscle pH, particularly in T2. Plasma biochemical analysis showed lower cholesterol, triglycerides, and LDL in all l-Cit groups, with optimal in T2 (p < 0.05), while HDL and uric acid remained unaffected. Moreover, rectal temperature decreased significantly across l-Cit groups (p < 0.05). Overall, this study suggests that a diet supplemented with 0.75 % l-Cit (T2), which could be a promising amino acid without affecting meat quality or consumer preferences, may improve growth performance, meat quality, the lipid profile (blood plasma), and thermoregulatio