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

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

Interactions of Energy Levels Offered to Holstein Cows Prepartum and Postpartum. II. Reproductive Performance¹

Department of Dairy Science, University of Arizona, Tucson 85721

ABSTRACT

Thirty-two cows were provided with 115% of their maintenance digestible energy requirements (low-prepartum) during the last six to eight weeks of gestation for comparisons with 32 cows fed 160% of their maintenance energy needs (high-prepartum). The 64 cows were factorially assigned to two energy levels postpartum. One group was fed alfalfa hay at 2% of body weight and enough concentrates to maintain relatively constant body weights through a complete lactation (high-postpartum). A second group was fed alfalfa hay at 2% of body weight and enough concentrates to satisfy the National Research Council energy recommendations of 1958 (low post-partum).

Average birth weights of 43.6 kg (low-prepartum), and 42.9 kg (high-prepartum) were not significantly different (P < .05). The percentages of the cows' uteri which had completely involuted by 45 days postpartum were 94 (low-prepartum-low-postpartum), 75 (low-prepartum-high-postpartum), 75 (high-prepartum-low-postpartum), and 88 (high-prepartum-high-postpartum). Days from calving to first estrus and calving intervals were 32.0, 390.0 (low-prepartum-low-postpartum); 46.9, 385.5 (low prepartum-high-postpartum); 47.8, 378.0 (high-prepartum-low-postpartum); and 42.9, 379.0 (high-prepartum-high-postpartum), respectively. Services required per conception averaged 2.1 (low-prepartum-low-postpartum), 1.6 (low-prepartum-high-postpartum), 1.9 (high-prepartum-low-postpartum), and 1.5 (high-prepartum-high-postpartum). None of the above differences was significant (P<.05).

¹ Arizona Agricultural Experiment Station Technical Paper no. 1466.

² Present address: Department of Animal Science, Brigham Young University, Provo, Utah 84601.