Effect of Two Different Biochars as a Component of Compound Feed on Nutrient Digestibility and Performance Parameters in Growing Pigs

The objective of this study was to examine two different biochars as a component of compound feed regarding their effects on nutrient digestibility and performance parameters in growing pigs. A total of 18 male, intact piglets (N = 18) aged 26 days with an initial bodyweight of 6.88 kg were divided into three homogeneous groups of six animals each (n = 6). Treatments were control (CON, no addition of biochar), 2 % biochar 1 (BC 1, diet containing 2 % biochar 1) and 2 % biochar 2 (BC 2, diet containing 2 % biochar 2). Before the start of the trial, the biochars were characterized regarding Brunnauer-Emmet-Teller (BET) surface area, surface energy, humidity and ash content. During the first six weeks a 3 x 3 Latin square was used to determine the apparent total tract digestibility (ATTD) of all three feed in each animal (N = 54, n = 18). On day 42, three new homogenous groups were formed with two animals from each of the previous groups. Each group received one of the three diets for four weeks. The different treatments revealed no effects on ADFI, ADWG or FCR (p > 0.05). The ATTD of dry matter, organic matter , ether extract, crude fiber and N-free extract was higher (p < 0.05) in pigs fed the biochar diets (BC1 and BC2) than in those animals fed the control diet. The greatest difference was found for ATTD of crude fiber, which was increased by 19.8 % respectively 23.8 % (CON: 30.8b ± 13.4 %; BC 1: 38.4a ± 8.2 %; BC 2: 40.4a ± 12.2 %). ATTD of crude protein was only higher in BC 2 compared to CON (CON: 81.0b ± 4.1 %; BC 1: 82.4ab ± 3.6 %; BC 2: 84.2a ± 3.4 %). The results indicate that no negative effects can be expected when biochar is included in the feed for growing pigs.