title: [Fetal heart rate measurement and sonographic fetometry for determination of fetal age in sheep].
abstract: Fetal heart rate was repeatedly measured in 84 ewes of different breeds during gestation. The Doppler system (83 measurements) and the real-time M-Mode ultrasound system (221 measurements) were used. Furthermore the following fetometric parameters were ascertained in 13 pregnant ewes sonographically once a week: crown-rump-length, width of the head, inter-eye distance, height of the lateral thorax in the region of the cardial septum and caudal of the sternum, as well as the diameter of the thorax and abdomen in each case latero-lateral and ventro-dorsal. The following influencing factors were tested by means of group regression analyses and multiple regression analysis: days before parturition, method of examination, litter size and later birth weight of lams, and heart rate, breeds and diseases of the ewes. A significant regression exists between the days before parturition (d.b.p.) and fetal heart rate (fhr): y (fhr) = 139 + 0.94 x (d.b.p.); r = 0.781 p < 0.001; n = 304. No significant influence was proved for the birth weight, litter size, maternal heart rate, method of examination, breed and health state of the ewes on the fetal heart rate. All fetometric parameters were significantly correlated with the days before parturition. This regression was most evident for the measured value of the ventro-dorsal abdomen (abd. vd., mm): y (abd. vd) = 114.2 -0.966 x (d.b.p.); r = -0.958; p < 0.001, n = 128. The litter size influenced the regression with a significance of p < 0.05. The fetometry is more appropriate for the determination of gestational age and the prediction of parturition than the measurement of the fetal heart rate.
authors.affiliation: Klinik für kleine Klauentiere und forensische Medizin, Tierärztlichen Hochschule Hannover.
authors.forename: J
authors.initials: J
authors.lastname: Chavez Moreno
authors.forename: C
authors.initials: C
authors.lastname: Steinmann Chavez
authors.forename: K
authors.initials: K
authors.lastname: Bickhardt
mesh_terms: D000818:Animals; D001724:Birth Weight; D002417:Cattle; D005314:Embryonic and Fetal Development; D005260:Female; D005333:Fetus / Q000033:anatomy & histology*; D006339:Heart Rate; D006340:Heart Rate, Fetal; D007743:Labor, Obstetric; D011247:Pregnancy; D012044:Regression Analysis; D012756:Sheep; D012757:Sheep Diseases / Q000453:epidemiology*; D016216:Ultrasonography, Prenatal / Q000662:veterinary*
vernacular_title: Fetale Herzfrequenzmessung und sonographische Fetometrie zur Bestimmung des Trächtigkeitsstadiums beim Schaf.