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 Reid, R. L. Articles by Daniel, K. Search for Related Content PubMed Articles by Reid, R. L. Articles by Daniel, K.

Effects of Nitrogen and Micro-Element Fertilization on Quality of Pasture and on the Health, Nutritional Status and Reproductive Performance of Sheep^1,2,

West Virginia University, Morgantown 26506

Abstract

The data obtained in this study indicate that, in general, nitrogen fertilized orchardgrass in the form of pasture or hay provided an adequate source of most nutrients for a breeding flock of ewes over an extended period of time. A requirement for supplemental P was evident across all treatments after 1 year, although P levels in the forage were adequate by N.R.C. standards. Nitrogen and available energy concentrations in the herbage and hay were apparently adequate, with the exception of 1 year in which the feeding of a poor quality, late-cut hay during the latter part of pregnancy resulted in impaired reproductive performance in ewes and adverse effects on the health and growth of lambs on the low- and medium-N fertilization treatments.

Increasing increments of N fertilizer, and the incorporation of micro-elements at a high level of N, had certain specific effects on metabolism and performance of sheep. In the first year, a higher incidence of thyroid abnormalities was noted in lambs born from ewes on the high N treatments. Although ewes on the high N and high N + micro-element treatments maintained higher body weights during pregnancy, birth weight of lambs born from ewes on these treatments tended to be lower. High levels of N fertilization depressed the intake of herbage in spring, but little effect was noted on body weight of the ewes during the spring to autumn grazing season.

¹ Published with the approval of the Director of the West Virginia Agricultural Experiment Station as Scientific Paper No. 1261.

² The authors wish to express their appreciation to E.C. Townsend and E.J. Harner, Jr. for advice on statistical analysis of data. The study was carried out with financial support from HEW, PHS Grant No. ES 00150-02; micro-element fertilizers were supplied by TVA.

³ Present address: U.S. Regional Pasture Research Laboratory, University Park, Pa. 16802.

⁴ Present address: Agricultural Research Service, U.S. Department of Agriculture, Fort Reno Livestock Research Station, El Reno, Ok. 73036.