Ruminal protein and fibre degradability of lucerne hay as affected by regrowth period and dairy breed

Date
2011
Journal Title
Journal ISSN
Volume Title
Publisher
South African Society for Animal Science
Abstract
The chemical composition of roughages constantly changes while it grows towards maturity. The effective dry matter (DM), crude protein (CP) and neutral detergent fibre (NDF) degradabilities of lucerne hay (LH), harvested after regrowth periods of 4, 5 or 6 weeks, were determined in ruminally cannulated Holstein and Jersey cows by using the in sacco nylon bag technique. The degradabilities of DM and NDF across breeds differed between the LH harvested after the regrowth periods of 4, 5 and 6 weeks. Increasing the regrowth period of LH from 4 to 6 weeks significantly reduced effective DM degradability (k p = 0.08) from 59.0% to 51.2% and NDF degradability from 30.8% to 21.2%. Crude protein degradability tended to decrease with advancing maturity, with values of 77%, 73% and 74% after 4, 5 and 6 weeks' regrowth, respectively. Effective degradability of DM, CP and NDF did not differ between Holstein and Jersey cows. The results from this study suggest that LH harvested after a shorter regrowth period is of a higher quality in terms of DM, CP and NDF degradability which decreases as the plants mature.
Description
CITATION: Cruywagen, C. W., Muller, C. J. C. & Du Toit, F. J. 2011. Ruminal protein and fibre degradability of lucerne hay as affected by regrowth period and dairy breed. South African Journal of Science, 41(4):389-397.
The original publication is available at https://www.sasas.co.za/
Keywords
Alfalfa, Forage, Dairy cattle breeds, Nutrition
Citation
Cruywagen, C. W., Muller, C. J. C. & Du Toit, F. J. 2011. Ruminal protein and fibre degradability of lucerne hay as affected by regrowth period and dairy breed. South African Journal of Science, 41(4):389-397