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 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 Johnson, J. C. Articles by Knox, F. E. Search for Related Content PubMed PubMed Citation Articles by Johnson, J. C., Jr. Articles by Knox, F. E.

Persistence of Phosvel in Corn Silage and Effects of Feeding Dairy Cows the Treated Silage¹

Department of Animal Science, Coastal Plain Station, Tifton, Georgia 31794

M. C. Bowman and D. B. Leuck

Entomology Research Division, USDA, Tifton, Georgia

F. E. Knox

Animal Science Research Division, USDA, Tifton, Georgia

ABSTRACT

Corn treated in the field with Phosvel [O-(4-bromo-2-5-dichlorophenyl) O-methyl phenylphosphonothioate] at rates of .0, .56, 1.12, and 2.24 kg/hectare was ensiled 1 day later and subsequently fed to 16 lactating cows (4 per treatment). Silages produced from treated corn and fed during 8 weeks following 62 days from ensiling contained 56 to 66% of the ensiled Phosvel. Ingesting Phosvel and its phenol at averages of .41 to 1.71 mg per kilogram body weight did not affect (P>.05) silage dry matter intakes even though blood cholinesterase was measurably, but not critically, lowered (P<.05). Cows fed silage from the high treatment had greater body weight gains (P<.05) but produced less milk (P<.05) than cows fed control silage; thus, Phosvel residues seemed to effect a preferential formation or utilization of nutritive metabolic products or both for synthesizing body tissues rather than milk. Residues of Phosvel were present in milk, feces, and urine of all cows fed treated silage, but the highest mean residues in milk at any sampling were .244±.012 ppm Phosvel and .030±.003 ppm phenol. Except for an average of only .012 ppm Phosvel in milk from cows fed the high residue treatment, the milk, urine, and feces were free of residues within 1 week after feeding of the treated silage was terminated.

¹ University of Georgia, College of Agriculture Experiment Stations, Coastal Plain Station, Tifton, Journal Series Paper 1099.