Table 2.
Non-comprehensive list of recent studies showing the effects of probiotics modifying gut microbiota on behaviors in poultry.
| Birds/Treatment | Effects | Conclusion | Reference | |
|---|---|---|---|---|
| Layers | L. rhamnosus (5 × 109 CFU/mL) in-drinking water of stressed HFP birds, LFP birds, & a unselected pullets | Pecks (phenotypic and genotypic) had lower plasma TRP. L. rhamnosus caused a short-term increase in plasma TRYP and the TRP:(PHE + TYR) ratio and all subsets of T cell proportions. |
A transient effect on the immune and TRP catabolism with minimal changes in behavior in pullets. | [126] |
| L. rhamnosus (5 × 109/mL) in-drinking water of chronic stressed adult HPF & LPF hens |
L. rhamnosus prevented stress-induced FP. L. rhamnosus increased T cells in the spleen and cecal tonsil. L. rhamosus reduced cecal microbiota dysbiosis. |
Reduces stress-induced FP; and improves hen welfare. | [173] | |
| L. rhamnosus (5 × 108 CFU/mL) orally fed peckers & non-peckers | L. rhamosus caused ↑cecal contractions and their amplitude; It positively correlated with the number of FP of peckers. | Impacted gut motility with FP phenotypic effects. | [148] | |
| B. subtilis (1 × 106 CFU/g) fed dominant & subordinate hens |
B. subtilis caused ↓threat kick and ↓aggressive pecking during paired aggression test, and ↓plasma serotonin. B. subtilis caused ↓HS-associated behavior but ↑eating, foraging, standing, and walking. B. subtilis led to ↓hepatic IL-6, HSP70, cecal IgA & IgY but ↑hepatic IL-10. |
Dietary probiotic could be a suitable strategy for controlling aggression in chickens. | [178] | |
| Broilers | B. subtilis (1 × 106 CFU/g) fed HS broilers | Reduces HS-induced inflammatory reactions via the microbiota-immune axis, while increases broilers to copy HS more effectively. | [179] | |
| * A synbiotic fed HS broilers | Snybiotic fed birds had a shorter latency to make the first vocalization, with higher vocalization rates during the isolation test and a greater number of birds reached the observer during the touch test. | The synbiotic can reduce the fear response and stress state of HS broilers. | [177] | |
| Turkeys | B. amyloliquefaciens fed turkey poults | Probiotic increased the feeding time and decreased distress call and aggressive behaviors. | Probiotics regulates behavior in turkey poults via modulation of gut microbiota. | [180] |
| Quails | P. acidilactici (2.54 × 106/g) fed STI & LTI quails | Probiotic reduces immobility duration of STI birds during TI test. | The probiotic affected host behavior and memory via the effects on gut microbiota | [176] |
B. amyloliquefaciens: Bucillus amyloliquefaciens; B. subtilis: Bacillus subtilis; CMP: cecal microbiota transplantation; FP: feather pecking; HMT: homologous microbiota transplantation from the same line; HPF: high feather pecking birds; HS: heat stress; HSP: heat shock protein; IL: interleukin; L. rhamosus: Lactobacillus rhamnosus; IL: interleukin; LFP: low feather pecking birds; LTI: long tonic immobility quails; P. acidilactici: Pediococcus acidilactici; PHE: phenylalanine; STI: short tonic immobility quails; T: T lymphocytes; TI: Tonic immobility test; TRP: tryptophan; TYR: tyrosine. * Synbiotic consisted of a probiotic (Enterococcus faecium, Pediococcus acidilactici, Bifidobacterium animalis, and Lactobacillus reuteri) and a prebiotic (fructooligosaccharides).