Abstract:
This study was conducted to investigate the impact of guanidinoacetic acid (GAA) on layer hen performance, egg quality and hen health and whether GAA may contribute towards energy available to the hen. Six hundred Lohmann Brown layer hens were placed in individual cages and used for experimental purposes from point-of-lay at 18 weeks-of-age until termination of study at 34 weeks-of-age.
The 600 pullets were divided into six dietary treatments with 10 replicates per treatment. The six dietary treatments consisted of two main effects, i.e., diet energy concentration and the inclusion of a GAA containing product, CreAMINO. Each of two energy concentrations (standard or reduced) were combined with one of three levels of CreAMINO (0, 0.08% or 0.12%). The effect of CreAMINO supplementation was combined with a reduced dietary energy level to test for a possible energy-sparing effect in layer hens. If an increase in GAA in the diet can lead to an increase in creatine and ATP, a subsequent increase in available energy is possible. Therefore, less energy will be needed via the feed. A lower energy dense diet supplemented with GAA, may have the same effect as a standard or high energy diet without containing GAA.
Over a period of 18 weeks, bodyweight, feed intake, egg production, egg quality and liver and gut health were measured. The feed efficiency and energy efficiency were also calculated at the end of the trial. Feed conversion ratio (FCR) was calculated as gram of feed per gram of egg produced. Feed consumed per dozen of eggs produced, was also recorded. Energy efficiency was determined by dividing the calculated energy intake with the weight of eggs produced. The overall results showed that hens did compensate for a reduced energy diet by increasing feed intake, whether supplemented with CreAMINO or not. CreAMINO treatment had no significant effect on any of the parameters. There were, however, some negative effects of CreAMINO on liver health, although none of it detrimental. Due to the higher feed intake of the hens from the reduced energy group, compared to the hens receiving the standard diet, no energy-sparing effect was observed in the hens. In the case where an energy-sparing effect was present due to CreAMINO, all hens across different treatment groups would have had the same feed intakes.
The results showed that no positive effects could be seen on hen performance, hen health, or egg quality by supplementing CreAMINO to the diets of early to peak layer hens.