Table 1.
Information extracted from five studies testing the effect of four products in reducing the concentration of Campylobacter in free-range broilers
| Article | [27] | [28] | [29] | [26] | [26] | [25] |
|---|---|---|---|---|---|---|
| Composition (product name) | Ferric tyrosine chelate (TYPLEX® Chelate) | Ferric tyrosine chelate (TYPLEX® Chelate) | Ferric tyrosine chelate (TYPLEX® Chelate) | Saccharomyces cerevisiae fermentate (Original XPC®) | Butyrate coated on microbeads (Adimix® Precision) | Formic acid, acetic acid, propionic acid and sorbic acid (Selko® 4Health) |
| Type of product | Not classified | Not classified | Not classified | Prebiotic | Short-chain fatty acid | Short-chain fatty acids |
| Administration | Feed additive | Feed additive | Feed additive | Feed additive | Feed additive | Water additive |
| Randomization described | Yes | Yes | Yes | Yes | Yes | No |
| Blinding used | No | No | No | No | No | No |
| Establishment baseline infection status prior to intervention | No | No | Yes | Yes | Yes | No |
| Passive infection of broilers via the environment | Yes | Yes | Yes | No | No | Yes |
| Field study conditions | No | No | No | No | No | Yes |
| Country of study | United Kingdom | Scotland | Greece | France | France | Germany |
| Control group (N) | 5 | 10 | 16 | 44 | 44 | 5 |
| Intervention group (N) | 5 | 10 | 16 | 15 | 15 | 4–5 |
| Repeats (N) | 6 | 10 | 6 | 1 | 1 | 3 |