Authors

Abstract

The effect of feeding of soaked barley straw on milk production and composition and rumen characteristics was studied. The degradability of soaked barley straw (for 24, 48 and 72 hours) and unsoaked barley straws were studied in the first experiment. The unsoaked barley straw had more readily degraded fraction (a) than soaked straw treatments (p> 0.05). There was no significant difference between slowly degradable fractions (b) and degradation rates (c, %h) in various treatments of barley straw. The degradability parameters of different rations also studied. The differences between readily (a) and slowly (b) degradable fractions were not significant. In the second experiment the effect of partial replacement of alfalfa hay with unsoaked barley straw and 24h soaked barley straw on performance of 9 multiparous lactating dairy cows in midlactation (580.9 ± 39.3 BW) with 27.8 ± 4.5 kg daily milk yield was studied in a crossover design. The effects of different treatments on milk yield (p< 0.05), milk fat (g/kg yield) (p< 0.05), N-NH3 rumen liquor (p< 0.0001), rumination and chewing activity (min/d) were significant. The rumination and chewing activity (min/d) were increased in diets that contained barley straw. In conclusion utilization of soaked barley straw in ration of midlactation cows is recommended.

Keywords

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