HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Interpretive Summary Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Zhong, R. Z. Articles by Ren, G. P. Search for Related Content PubMed PubMed Citation Articles by Zhong, R. Z. Articles by Ren, G. P.

Effects of Substitution of Different Levels of Steam-Flaked Corn for Finely Ground Corn on Lactation and Digestion in Early Lactation Dairy Cows

R. Z. Zhong^*,, J. G. Li, Y. X. Gao, Z. L. Tan^*,1 and G. P. Ren

^* Key Laboratory of Subtropical Agro-Ecological Engineering, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan 410125, P. R. China
Graduate University of the Chinese Academy of Sciences, Beijing 100039, P. R. China
Agricultural University of Hebei, Baoding 071001, P. R. China
Central South University of Forestry and Technology, Changsha, Hunan 410004, P. R. China

¹ Corresponding author: zltan{at}isa.ac.cn

Eight multiparous Holstein cows, 4 of them fitted with rumen cannulas, were used to test the effects of substitution of steam-flaked corn (SFC) for equal amounts of finely ground corn (FGC) in diets on feed intake and digestion, blood metabolites, and lactation performance in early lactation dairy cows. Cows were fed 4 diets in a replicated 4 x 4 Latin square design. The fistulated cows formed 1 replicate. Each experimental period lasted for 3 wk. The 4 diets contained 0, 10, 20, or 40% SFC and 40, 30, 20, or 0% FGC (dry matter basis), respectively. The milk protein content and yield, milk solid nonfat content and yield, plasma glucose concentration, and dry matter intake increased as the proportion of SFC increased in diets. Apparent total tract digestibilities of dry matter, organic matter, neutral detergent fiber, acid detergent fiber, and average ruminal fluid NH₃-N concentration decreased with increasing levels of SFC. The ruminal fluid pH was not affected by the substitution of SFC for FGC. The 20% SFC substitution improved digestion of crude protein, yield of fat-corrected milk, milk lactose content, fat, and fat yield. The 40% SFC substitution increased urea concentration in both plasma and milk. It was concluded that 20% of SFC substitution for FGC appeared to be an appropriate level in diet for early lactation dairy cows.

Key Words: steam-flaked corn • milk composition • digestibility • dairy cow