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bioRxiv · 10.1101/2020.08.07.241174

Effect of oxidized β-carotene-oxygen copolymer compounds on health and performance of pre- and post-weaned pigs

Abstract

The discovery that a naturally occurring, biologically active {beta}-carotene-oxygen copolymer compound is the main product formed in spontaneously oxidized {beta}-carotene has stimulated interest in its potential health benefits. The copolymer, formed in nature or synthetically by the air-oxidation of {beta}-carotene, possesses beneficial immune modulating activities that previously had been attributed to {beta}-carotene itself. Support for these benefits is provided by previous studies showing that supplementation in feed with low parts-per-million levels of copolymer-rich, fully oxidized {beta}-carotene (OxBC) helped reduce the negative impact of subclinical necrotic enteritis in broilers and improved growth in weaned piglets. To further assess these potential benefits, two trials were conducted in swine raised under commercial conditions in Vietnam. Trial 1, a 140-day full-grow, post-wean study with 500 28-day-old pigs, compared 2, 4 or 8 ppm OxBC against both an unsupplemented and an antibiotic control group. OxBC and antibiotics each improved growth rate, feed efficiency, and body weight compared to the control (P<0.001). Animals receiving 4 and 8 ppm OxBC performed better than did animals on antibiotics (P<0.001). In starter pigs, OxBC reduced the occurrence of diarrhea dose-dependently (4 and 8 ppm) and to a greater extent than did antibiotics (P<0.001). Trial 2, a 49-day study with 420 piglets, was conducted in two-stages. In Stage 1 (pre-wean), OxBC in the transition (creep) feed produced a dose-dependent trend toward increased body weight over 21 days, reaching significance at the highest inclusion level (16 ppm) (P<0.001). In Stage 2 (post-wean), body weight gain showed a dose-dependent trend and was significant for both 8 ppm OxBC and the antibiotics at 28 days post-wean (P<0.001). Feed conversion was better at 8 ppm OxBC and for the antibiotic group (P<0.001). These findings support the concept that {beta}-carotene-oxygen copolymers help optimize immune function, and provide validation for the effectiveness of this strategy in enhancing animal performance in the absence of in-feed antibiotics.

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Burton, G. W., Van Kinh, L., Riley, W. W., Nickerson, J. G., Vinh, D., Van Phu, N., Van, N. T., Huyen, L. T. T.. 2020-08-07. Effect of oxidized β-carotene-oxygen copolymer compounds on health and performance of pre- and post-weaned pigs. https://doi.org/10.1101/2020.08.07.241174

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