Digestibility and metabolism of dietary guanidino acetic acid fed to broilers

Abstract

In two feeding experiments the retention of supplemental guanidine acetic acid (GAA) in broilers was investigated. In both experiments, the same three treatments were used; the basal feed was supplemented with 0, 0.6, or 6.0 g GAA per kg of feed. While in a growth study (experiment 1) day-old, male Ross 308 broilers were fed diets for 35 days, these diets were fed for only 8 days to fistulated broilers 34 days of age in a balance study (experiment 2). Feeding 0.6 g/kg GAA did not improve growth performance whereas 6.0 g/kg GAA resulted in a reduction of feed consumption and consequently of weight gain (P ≤ 0.05). Feed conversion was not affected and was 1.48 to 1.49 in all treatments. Increasing levels of dietary GAA gradually increased the creatine concentration in breast muscle and liver tissues (P ≤ 0.05) indicating a transformation and retention of dietary GAA as creatine. In experiment 2 the non-supplemented basal diet allowed us to determine the endogenous GAA, creatine, and creatinine excretions. Accordingly, only small amounts of these metabolites were recovered in feces while they were much higher in urine. Increasing dietary GAA intake increased fecal and renal GAA, creatine, and creatinine excretion and was significant (P ≤ 0.05) at 6.0 g/kg dietary GAA compared to no or 0.6 g/kg GAA supplementation. The mean true fecal digestibility of GAA (99%) was unaffected by the level of supplemental GAA. Considering renal GAA excretions, true availability of supplemental GAA was reduced with increasing dose (83% vs. 71%; P ≤ 0.05). Taking into account creatine and creatinine excretions above those of the basal diet, as they are a consequence of increasing dietary supply, true availability of supplemental GAA shrank from 76% (0.6 g/kg GAA) to 46% (6.0 g/kg GAA; P ≤ 0.05). Changes in blood creatine and creatinine levels reflected the changes observed in the liver and muscle tissues and may suggest increased transport to excretion organs. Data from these experiment were used to estimate the creatine requirement.

Mısır-Soya Küspesi Diyetine Eklenen Guanidino Asetik Asitin Yumurta Tavuklarının Üretim Performansı, Kan Biyokimyasal Parametreleri ve Üreme Hormonlarına Etkisi

“…Findings showed that GAA addition to diet had not significant effects on productive performance but 0.171% GAA addition decreased egg weight from 2 th week to [24,25] . However, Michiels et al [7] observed only slightly increase in FI of broiler chicks fed with GAA.…”

“…FCR was no influenced by GAA treatments and positive control (2% meat meal); showing that creatine supplementing from each source had not significant effect on the mentioned parameter. Tossenberger et al [24] stated that GAA addition to diet had not significant effect on FCR of broiler chicks. Other studies have shown that GAA addition to diet lowered FCR in broiler chicks [2,5,[25][26][27] .…”

Effects of dietary supplementation of guanidino acetic acid on growth performance, thigh meat quality and development of small intestine in Partridge-Shank broilers

“…However, the present average live weights were less than 2000 g after 60 days' growth, and this may be related to the genetics of the broilers (female Partridge-Shank) used in the present trial. Lemme et al (2007a) reported that the optimum supplemental concentration of GAA ranged from 0.6 to 1.2 g/kg DM of feed, whereas 6.0 g/kg GAA would reduce feed consumption and consequently weight gain (Tossenberger et al, 2016). These reasons Results are means of six pens corresponding to 30 broilers for each treatment.…”

Performance, antioxidant status, nutrient retention and serum profile responses of laying Japanese quails to increasing addition levels of dietary guanidinoacetic acid

“…Guanidinoacetic acid (GAA), as a creatine precursor, has received growing attention in poultry nutrition, mainly because most of the current poultry diets formula are relying on vegetable products, which compared to animal-based ingredients are devoid of creatine (Michiels et al 2012). Creatine and its metabolite, phosphocreatine, are used to replenish adenosine triphosphate (ATP) to prevent the energy depletion of the cells (Tossenberger et al 2016). After the synthesis of GAA in the kidneys, through the catalytic effect of arginine: glycine amidinotransferase, GAA is transferred to the liver for the conversion to creatine.…”