Elsevier

Journal of Dairy Science

Volume 77, Issue 2, February 1994, Pages 522-532
Journal of Dairy Science

Article
Altered Ruminal Mat Consistency by High Percentages of Soybean Hulls Fed to Lactating Dairy Cows1

https://doi.org/10.3168/jds.S0022-0302(94)76980-0Get rights and content
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Abstract

Three ruminally fistulated dairy cows in early lactation were used in a 3 × 3 Latin square design with 3-wk periods to investigate the effects of alteration of ruminal mat consistency on ruminal function and soybean hull rate of passage. The control diet consisted of 60% forage (alfalfa:corn silages, 1:1, dry basis) and no soybean hulls. Replacement of 40% of the silage mixture with soybean hulls decreased ruminal mat consistency by 57% at 6 h postfeeding and reduced rumination activity 52%, ruminal pH 6%, and acetate:propionate ratio observed over 24 h by 10% compared with the control diet. Replacement of 75% of the silage with 25% soybean hulls combined with 20% coarsely chopped alfalfa hay increased ruminal mat consistency by 49% at 2 and 6 h postfeeding, increased the percentage of large particles (≥9.50 mm) retained in the dorsal rumen, and significantly increased ruminal pH 1.5% and acetate:propionate ratio by 17% compared with the diet of 25% soybean hulls without alfalfa hay. Increasing the ruminal mat consistency with coarsely chopped alfalfa hay did not significantly decrease the rate of escape of soybean hulls from the rumen, but addition of alfalfa hay increased 4% FCM 4.8 kg/d compared with FCM of diets containing 25% soybean hulls without alfalfa hay.

Key words

soybean hulls
specific gravity
ruminal mat consistency
rate of passage

Abbreviation key

HSH
high SH diet with (+) or without (−) hay
SH
soyhulls

Cited by (0)

1

Published with the approval of the director as Paper Number 10370, Journal Series, Nebraska Agricultural Research Division.

2

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