Login | Create Account (DAF staff only)

Supplementation of cattle fed tropical grasses with microalgae increases microbial protein production and average daily gain

Costa, D. F. A. and Quigley, S. P. and Isherwood, P. and McLennan, S. R. and Poppi, D. P. (2016) Supplementation of cattle fed tropical grasses with microalgae increases microbial protein production and average daily gain. Journal of Animal Science, 94 (5). p. 2047. ISSN 1525-3163

Full text not currently attached. Access may be available via the Publisher's website or OpenAccess link.

Article Link(s): http://dx.doi.org/10.2527/jas.2016-0292

Abstract

A series of 3 experiments were conducted to evaluate the use of microalgae as supplements for ruminants consuming low-CP tropical grasses. In Exp. 1, the chemical composition and in vitro protein degradability of 9 algae species and 4 protein supplements were determined. In Exp. 2, rumen function and microbial protein (MCP) production were determined in Bos indicus steers fed speargrass hay alone or supplemented with Spirulina platensis, Chlorella pyrenoidosa, Dunaliella salina, or cottonseed meal (CSM). In Exp. 3, DMI and ADG were determined in B. indicus steers fed speargrass hay alone or supplemented with increasing amounts of NPN (urea combined with ammonia sulfate), CSM, or S. platensis. In Exp. 1, the CP content of S. platensis and C. pyrenoidosa (675 and 580 g/kg DM) was highest among the algae species and higher than the other protein supplements evaluated, and Schizochytrium sp. had the highest crude lipid (CL) content (198 g/kg DM). In Exp. 2, S. platensis supplementation increased speargrass hay intake, the efficiency of MCP production, the fractional outflow rate of digesta from the rumen, the concentration of NH3N, and the molar proportion of branched-chain fatty acids in the rumen fluid of steers above all other treatments. Dunaliella salina acceptance by steers was low and this resulted in no significant difference to unsupplemented steers for all parameters measured for this algae supplement. In Exp. 3, ADG linearly increased with increasing supplementary N intake from both S. platensis and NPN, with no difference between the 2 supplements. In contrast, ADG quadratically increased with increasing supplementary N intake from CSM. It was concluded that S. platensis and C. pyrenoidosa may potentially be used as protein sources for cattle grazing low-CP pastures.

Item Type:Article
Business groups:Animal Science
Subjects:Animal culture > Cattle
Animal culture > Rangelands. Range management. Grazing
Animal culture > Feeds and feeding. Animal nutrition
Deposited On:05 Jul 2016 04:03
Last Modified:05 Jul 2016 04:03

Repository Staff Only: item control page