The efficacy of organic acid, medium chain fatty acid and essential oil based broiler treatments; in vitro anti-Campylobacter jejuni activity and the effect of these chemical-based treatments on broiler performance

Aims This research tested the anti-Campylobacter properties of organic acids (OA), medium chain fatty acids (MCFA) and essential oils (EO) in vitro and commenced in vivo suitability testing focused on broiler performance. Methods and Results Nine active compounds were tested at different concentrations and times against Campylobacter jejuni in sterile distilled water, Mueller Hinton broth and grower feed digestate (GFD). Sodium caprate (1.5%, v/v), thymol (0.25% and 2.5%, v/v), carvacrol (1.25%, v/v) and potassium sorbate (1.5%, v/v) each achieved C. jejuni reductions of >= 4.5 log(10) CFU per ml in GFD, the matrix most representative of the broiler gut, after 60 s. Similar reductions were achieved after 60 min with lactic acid (1.25%, v/v), formic acid (3.1%, v/v), sodium caprylate (1.5%, v/v) and carvacrol (1.25%, v/v). However, in vivo these compounds adversely affected broiler performance, resulting in dimished water intake and reduced weight. Conclusions OA, MFCA and EO based compounds are effective anti-Campylobacter treatments in laboratory model studies but cannot be applied in vivo. Significance and Impact of the Study This study illustrates that OAs, MCFAs and EOs can achieve significant reductions in Campylobacter in vitro but identifies a major issue, inhibition of broiler performance, preventing their use in practice.