A novel combination of Butyric and Valeric acid glycerol esters with oregano oil in a dry powder form was evaluated for performance improvements in broilers. The dosing regimen (500 g/Ton feed in starter and grower; 250 g/Ton in finisher feed) was considered low compared to conventional practices using non-esterified Butyric and Valeric short-chain fatty acids (SCFA). Six trials were conducted at various trial facilities in Italy, United Kingdom, Spain, and Poland. Supplemented broilers weighed significantly more than the control birds at 28 days of age (+3.4%; 1459 g vs. 1412 g; p = 0.0006) and at 42 days of age (+2.5%; 2834 g vs. 2763 g; p = 0.0030). Supplementation significantly reduced mortality from 1.9% to 0.8% during the finisher phase (from 29 to 42 days of age); however, average mortality was 3.2% for the whole 42-day growth period and was not affected. Further, supplemented broilers grew more (66.4 vs. 64.5 g/day; p = 0.0005), ate more feed (104.7 vs. 103.1 g/day; p = 0.0473), converted feed significantly more efficiently (1.58 vs. 1.60; p = 0.0072), leading to better EPEF value (410 vs. 389; p = 0.0006) than the control broilers. Meta-analysed trial performance data for novel SCFA formulations such as these are not commonly available, and serve to facilitate efficacy determination from an end-user perspective. The use of short- and medium-chain fatty acid esters in optimal low-dose combinations to reliably augment gut health and performance appears promising in commercial broiler production, and may lead to further improvements in industry practices and reduced antibiotic use.
Keywords: Butyric; European poultry efficiency factor; Valeric; body weight; feed conversion ratio; gut health; performance; short-chain fatty acids.