Two experiments were conducted to determine the effects of feeding chromium propionate (Cr; Kemin Industries, Inc., Des Moines, IA) and a Yucca schidigera-based extract (YS; Distributors Processing, Inc., Porterville, CA) on growth performance of finishing pigs housed in commercial conditions. In experiment 1, a total of 1,188 pigs (PIC 337 × 1050; initially 27.3 ± 0.48 kg body weight [BW]) with 27 pigs per pen and 11 pens per treatment were split by sex upon arrival at the facility and were randomly allotted to groups of four pens blocked by BW. Diets were corn-soybean meal-dried distillers grains with solubles-based and were fed in five phases. Treatments were arranged as a 2 × 2 factorial with main effects of Cr (0 vs. 200 µg/kg) or YS (0 vs. 62.5 mg/kg YS-based feed grade concentrate). Overall, adding Cr alone increased (P = 0.049) average daily feed intake (ADFI), and inclusion of YS resulted in a marginally significant increase (P = 0.077) in ADFI. Backfat depth was increased (P = 0.043) and lean percentage was decreased (P = 0.011) with added Cr. In experiment 2, a total of 2,430 pigs (PIC 359 × 1050; initially 29.3 ± 0.43 kg BW) were placed in balanced mixed-sex pens with 27 pigs per pen, blocked by average pen BW, and randomly assigned to one of six dietary treatments with 14 pens per treatment. Diets were corn-soybean meal-based and were formulated in five dietary phases. Treatments were arranged in a 2 × 3 factorial with main effects of Cr (0 vs. 200 µg/kg added Cr), and YS extract (0, 62.5, or 125 mg/kg YS-based feed grade concentrate). Overall, a marginally significant (linear, P = 0.072) Cr × YS interaction was observed for average daily gain (ADG) where there was insufficient evidence of a difference with increasing YS in diets not including added Cr (P ≥ 0.109); however, ADG increased (quadratic, P = 0.026) with YS addition in treatments fed 200 µg/kg added Cr. For overall ADFI, a marginally significant (linear, P = 0.071) Cr × YS interaction was observed where YS increased ADFI with 200 µg/kg added Cr (linear, P = 0.031), however, did not when diets contained no added Cr (P = 0.700). A marginally significant reduction in gain:feed ratio was observed when 62.5 mg/kg YS was included (quadratic, P = 0.053), and final BW and hot carcass weight were lowest with 62.5 mg/kg YS (quadratic, P = 0.012). In summary, adding Cr propionate along with YS led to modest changes in performance with the greatest benefit observed with 200 µg/kg Cr and 125 mg/kg YS-based feed grade concentrate.
Keywords: chromium propionate; Yucca schidigera; finishing pigs.
Published by Oxford University Press on behalf of the American Society of Animal Science 2019.