Journal of Advanced Veterinary Research (Oct 2021)
Efficacy of Nano-Phytobiotics to Improve Growth Performance of Broiler Chickens: Evidence from a Meta-Analysis
Abstract
The ban of antibiotic growth promoters in many countries necessitate the need for alternatives. This study aimed to assess the growth-promoting potency of nano-phytobiotics (NP) on broiler chickens by using a meta-analysis approach. A systematic search was conducted using online databases. Data of average daily feed intake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were pooled using a random-effect model and the overall effect size was quantified using mean difference (MD). Heterogeneity among the studies was checked using I2 statistics. A total of 11 studies (31 comparisons) using 3,584 broiler chickens were involved in this meta-analysis. Inclusion of NP had no significant effect on ADFI (MD=-1.20 g/bird/d; P=0.157; I2=32%). However, NP significantly improved ADG (MD=2.16 g/bird/d; P=0.002; I2=90%) and FCR (MD=-0.09; P<0.001; I2=91%). Subgroup analysis revealed that NP significantly improved (P<0.05) ADG when the studies using dose of 45-200 and 1,000-10,000 ppm, as well as 42 d study period. Meta-regression analysis also indicated that ADG improvement significantly associated (P<0.05) with the NP dose and study duration, which could explain 21% and 20% of heterogeneity, respectively. This meta-analysis provides evidence that NP inclusion could improve ADG and FCR without alter ADFI on broiler chickens. However, their efficacy may vary according to the NP dose and study duration.