Performance, Carcass Yield, Muscle Amino Acid Profile, and Levels of Brain Neurotransmitters in Aged Laying Hens Fed Diets Supplemented with Guanidinoacetic Acid

Abstract

Guanidinoacetic acid (GA) is a natural precursor of creatine in the body and is usually used to improve the feed conversion and cellular energy metabolism of broiler chickens. The objective was to elucidate the effect of dietary supplementation of GA on carcass yield, muscle amino acid profile, and concentrations of brain neurotransmitters in laying hens. In total, 128 72-week-old ISA Brown laying hens were assigned to four equal groups (32 birds, eight replicates per group). The control group (T1) was fed a basal diet with no supplements, while the other experimental groups were fed a basal diet supplemented with 0.5 (T2), 1.0 (T3), and 1.5 (T4) g GA kg−1 diet. The T3 and T4 groups showed higher hen-day egg production and carcass yield compared to the control group (p = 0.016 and 0.039, respectively). The serum creatine level increased linearly with the increased level of dietary GA (p = 0.007). Among the essential amino acids of breast muscle, a GA-supplemented diet linearly increased the levels of leucine, isoleucine, phenylalanine, methionine, and threonine in the breast (p = 0.003, 0.047, 0.001, 0.001, and 0.015, respectively) and thigh (p = 0.026, 0.001, 0.020, 0.009, and 0.028, respectively) muscles. GA supplementation linearly reduced the level of brain serotonin compared to the control group (p = 0.010). Furthermore, supplementation of GA in the diet of laying hens linearly increased the level of brain dopamine (p = 0.011), but reduced the level of brain Gamma-aminobutyric acid (p = 0.027). Meanwhile, the concentration of brain nitric oxide did not differ between the experimental groups (p = 0.080). In conclusion, the dietary supplementation of GA may improve the carcass yield and levels of essential amino acids in the breast muscles, as well as the brain neurotransmitters in aged laying hens.

Investigation of structural and neurobiochemical differences in brains from high-performance and native hen breeds

“…This is confirmed by our behavioural studies, where Leghorns were defined as more active and fearful than Green-legged Partridge chickens 13,14 . Possibly, the lower concentration of dopamine in Leghorn hens is a result of a correlated and unintentional selection because, as reported by Ahmed-Farid et al 54 , laying hens selected for increased productive performance and survival exhibit a lower concentration of dopamine in www.nature.com/scientificreports/ the blood than hens selected towards low productivity and survival. At this point, it is also worth noting that the higher dopamine content in Green-legged hens may be directly associated with the higher content of copper in the brain, which is directly involved in the synthesis of this neurotransmitter 38 .…”

Guanidinoacetic Acid as a Nutritional Adjuvant to Multiple Sclerosis Therapy

“…Magnetic resonance spectroscopy revealed increased levels of total brain creatine, choline, N -acetyl aspartate, and glutathione, and a drop in glutamate levels at follow-up compared to levels evaluated at initial examination. Besides MS, several recent preclinical and clinical trials demonstrated positive effects of delivering GAA to the neural tissue ( McBreairty et al, 2015 ; Semeredi et al, 2019 ; Robinson et al, 2020 ; Ahmed-Farid et al, 2021 ; Seper et al, 2021 ; Adriano et al, 2022 ), corroborating its possible neurotropic potential in experimental and clinical nutrition.…”

Dietary guanidine acetic acid addition improved carcass quality with less back-fat thickness and remarkably increased meat protein deposition in rapid-growing lambs fed different forage types

“…Another prior study demonstrated that GAA supplementation increased the levels of Leu, Phe, Thr, Met, Arg, Glu, Pro, and His in the breast and thigh muscles of aged laying hens [12]. The present study demonstrated that the content of amino acids (Asp, Thr, Ser, Glu, Pro, Gly, Ala, Met, Ile, Leu, Phe, Lys, His, and Arg) and TAAs, EAAs, NEAAs, DAAs, BCAAs increased with UGAA or CGAA supplementation.…”

“…GAA increased the creatine supply had been shown in Holstein heifers [8]. It has been reported that GAA or creatine supplement in the diet help to affect muscle yield, and meat quality of pigs, broilers, and bulls [9][10][11][12][13]. For example, fattening pig diets supplemented with 0.12% GAA 60 days before slaughter improved lean meat yield, reduced backfat thickness [10].…”

“…Finishing gilts supplemented with 0.045% GAA improved meat quality by changing muscle ber characteristics and reducing mandibular fat [11]. In addition, GAA was found to improve carcass yield and levels of essential amino acids (EEAs) in the breast muscles of aged laying hens [12]. In ruminants, the administration of GAA (0.6 0.6 or 0.9 g/kg) has the potential to improve BW, ADG, and feed e ciency in Angus bulls [14].…”