A meta-analysis of the effects of dietary Spirulina on growth performance of broiler chicken

SUMMARY Spirulina (Spirulina platensis) has received attention as an alternative protein source and feed additive in animal diets. Many studies reported varying degrees of success in the growth performance of broiler chicken when fed diets containing Spirulina. In the present study, we investigated dietary effect of Spirulina on broiler chicken growth performance using a meta-analytical approach. The databases, WEB OF SCIENCE (1970–2021), SCOPUS (1939–2021) and Google Scholar were searched systematically to select studies for the analysis. A total of 28 studies were included in the analysis. The differences in growth performance parameters (i.e. feed intake, weight gain and feed conversion ratio) between the birds fed control diets and Spirulina diets were calculated using a standardised effect size; Hedges’ g. The meta-analysis showed that birds fed diets containing Spirulina improved weight gain and feed conversion ratio compared to those fed control diets. On the other hand, there was no difference in feed intake between the groups fed Spirulina diets and control diets. The present meta-analysis manifested that dietary inclusion of Spirulina could improve the growth performance of broiler chicken. In particular, the supplementation of low levels of Spirulina (i.e. less than 10%) in diets is more suitable to achieve higher growth performance in broiler chicken.