Funnel plots to assess the publication bias. (a) ADFI. (b) ADG. (c) CP. (d) GE. (e) GF. (f) La:Ec. (g) Fatty acids. ADFI: Average daily feed intake; ADG: Average daily gain; LB: Lactobacillus; Ec: Escherichia coli; V/VH: Villus height, C: Crypt depth, CP: Crude protein; GE: Gross energy; GF: Gain to Feed ratio, and La:Ec: Lactobacillus : E. coli La:Ec ratio.