PSXI-35 Effects of chitosan source, molecular weight and supplementation level on in vitro (RUSITEC) ammonia and methane production. (7th December 2018)

• Record Type: Journal Article
• Authors: Kirwan, S; Boland, T; Kelly, A; Serra, E; Rajauria, G; Pierce, K
• Is Part Of: Journal of animal science. Volume 96(2018)Supplement 3
• Page Start: 424
• Page End: 425
• Publication Date: 2018-12-07
• Subjects: Chitosan -- ammonia -- methane; Livestock -- Periodicals; Livestock; Electronic journals; Periodicals; 636.005
• DOI: 10.1093/jas/sky404.929
• Languages: English
• ISSNs: 0021-8812

Abstract

Abstract: Nitrogen excretion and methane emissions from ruminant production systems are growing environmental concerns. Natural feed additives with known antimicrobial activity are being investigated for their rumen fermentation modification potential and as a strategy to mitigate emissions from livestock. The objective of this study was to evaluate the effects of chitosan source, molecular weight and supplementation level on in vitro (RUSITEC) ammonia and methane production. The experiment consisted of two incubation periods using three RUSITEC systems (8 vessels/system). Treatments were as follows: C0 (control) zero chitosan; C1 chitosan molecular weight <5, 000 kDa (fungal origin); C2 chitosan molecular weight 10, 000 kDa (fungal origin); C3 chitosan molecular weight 20, 000 kDa (fungal origin); C4 chitosan molecular weight 3, 500 kDa (crustacean origin), fed at three different feeding levels 500 mg/l, 1, 000 mg/l and 1, 500 mg/l, replicated three times, resulting in a 5 x 3 factorial design. The basal diet contained 40:60 grass silage: concentrate on a dry matter (DM) basis. Rumen inoculum was sourced from eight rumen-cannulated beef heifers (667 ± 53 kg BW). The level of chitosan offered increased rumen ammonia concentration ( P < 0.01) but had no effect on any other variable measured ( P >0.10). In addition, C4 increased butyric acid production ( P <0.05). Rumen ammonia production was higher for the C2, C3, C4 treatments compared to C0 ( P <0.05). Methane production per day in C4 was higher ( P <0.05) compared to all other treatments. Under in vitro conditions, the inclusion of crustacean chitosan of low molecular weight can increase rumen ammonia, butyric acid and methane production.