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 Hulet, C. V. Search for Related Content PubMed PubMed Citation Articles by Hulet, C. V.

Pregnancy Diagnosis in the Ewe Using an Ultrasonic Doppler Instrument¹

U. S. Department of Agriculture

Abstract

An assessment of the value of two ultrasonic Doppler instruments for diagnosing pregnancy in the ewe at 56 to 135 days of gestation has been made on 243 ewes. Pregnancy detection was studied with ewes in both a standing and sitting position. The transducer was systematically placed at various locations on the wool-free area on the anterior margin of the udder or flank and the ultrasound beam rotated in a conical direction while coupled with a water soluble jelly. The characteristic sound of fetal heart beat, arterial pulse or fetal movement was taken as a positive indication of pregnancy. Ewes were examined for a maximum of 5 min. in flocks 1 and 2 and for a maximum of 2 min. in flock 3. No significant difference was found between examination position of the ewe nor make of ultrasonic Doppler instrument. All ewes but three diagnosed pregnant lambed or aborted. The greatest error was in ewes diagnosed non-pregnant which lambed. The over all accuracy in flock 1 (110 to 135 days pregnant) was 94%. In flock 2 (100 to 130 days pregnant), after one examination diagnostic accuracy was 92%. A second examination about 2 wk. after the first improved the over-all accuracy to 99%. Flock 3 (56 to 73 days pregnant) was tested much earlier in pregnancy than flocks 1 and 2. Diagnostic accuracy was only 61% at the first test when fetal movement was not included as a positive diagnosis. Diagnostic accuracy improved to about 95% (56 to 85 days pregnant) when fetal movement was added as a positive test, more experience was gained and the average age of fetuses was slightly greater. Using the best known procedures, diagnostic accuracy was 99% when the ewes were between 75 and 92 days pregnant.

¹ From the U. S. Sheep Experiment Station. Sheep and Fur Animal Research Branch, Animal Husbandry Research Division, A.R.S., Dubois, Idaho in cooperation with the University of Idaho, Moscow.