Pulsed wave–doppler ultrasonographic evaluation of mammary blood flows speed in cows during different productive periods

Abstract

Circulatory phenomena are complex organic functions that depend on several factors as blood viscosity, vascular walls elasticity, cardiac pump rhythm, discontinuous activity, various resistance to blood flow in tissues and spontaneous or induced vasomotor responses. Doppler ultrasonographic method is a valid tool for performing mammary blood flow recordings. Seven Bruna Italiana cows (average age 5 years) during 3 different period of lactation (40, 100, 210 days after the delivery) and during the dry period (290 days after the delivery) were used for our study. Systolic and diastolic flow speeds recordings of right and left external pudendal arteries (before the cranial and the caudal mammary bifurcation) were carried out on each subjects by means of a Pulsed Doppler System. By appliyng repeated measures ANOVA between the different lactation phases and the dry period systolic and diastolic blood flows both for right and left external pudendal artery showed the same pattern. The systolic speed of right and left external pudendal arteries showed the following statistical significances: systolic speed before milking (F(3,18) =37.71; P<0.0001, right artery morning; F(3,18) =30.91; P<0.0001, left artery morning; F(3,18) = 52.94; P<0.0001, right artery afternoon; F(3,18)=32.49; P<0.0001, left artery afternoon); diastolic speed before milking (F(3,18) =19.89; P<0.0001, right artery morning; F(3,18)=24.09; P<0.0001, left artery morning; F(3,18) =36.75; P<0.0001, right artery afternoon; F(3,18) =41.56; P<0.0001, left artery afternoon). No statistical significant differences were found after milking both in morning and in afternoon for the different lactation phases and the dry period. The obtained results give a contribution to the physiologic knowledges of the cow mammary activity and led us to better understand the complex vascular phenomena during the different lactation and dry periods.