Effects of oxytocin administration on doppler indices of mammary artery in postpartum ewes

Doğum sonrası uterus involüsyonunu hızlandırmak ve sütün indirilmesini sağlamak amacıyla sıklıkla uygulanan oksitosin hormonu vasküler tonusun düzenlenmesinde de etkilidir. Doppler ultrasonografi, doku ve organlara ait kan akımı özelliklerinin değerlendirilebilmesine olanak sağlayan oldukça pratik bir tekniktir. Bu çalışmada postpartum dönemdeki koyunlara uygulanan oksitosin hormonunun meme kan akımında oluşturduğu hemodinamik değişikliklerin incelenmesi amaçlandı. Çalışma tekiz kuzulamış olan 20 adet primipar Kıvırcık ırkı koyun ile gerçekleştirildi. Koyunlar randomize şekilde oksitosin ve kontrol gruplarına ayrıldı (her grup için n=10). Oksitosin ve kontrol gruplarına sırasıyla 10 IU/koyun dozda oksitosin ve 1 ml/koyun dozda serum fizyolojik doğum sonrası ilk üç gün boyunca günde 2 kez kas içi yoldan uygulandı. Puls Doppler ultrasonografi tekniği kullanılarak eksternal pudendal artere ait pulsatilite ve rezistans indeksleri (sırasıyla PI ve RI) ölçüldü. Oksitosin grubu daha yüksek PI ve RI değerlerine sahip olma eğiliminde olmasına karşın gruplar arasında anlamlı farklılık sadece birinci ve ikinci postpartum günlerin PI değerlerinde saptandı (sırasıyla p<0,001 ve p<0,05). Postpartum erken dönemdeki koyunlara uygulanan oksitosin hormonunun, meme arterinin direncini arttırdığı sonucuna ulaşıldı.Oxytocin hormone, which is frequently used in order to hasten uterine involution process and to ensure milk ejection, is also effective in regulation of vascular tone. Doppler ultrasonography is a highly practical technique that allows the evaluation of blood flow characteristics of tissues and organs. In this study, it was aimed to investigate the hemodynamic changes of mammary artery caused by oxytocin administration in postpartum ewes. The study was conducted with 20 primiparous Kivircik ewes which lambed singleton. The ewes were randomly divided into oxytocin and control groups (n=10 for each group). A dose of 10 IU/sheep oxytocin and 1 ml/sheep saline solution were administered intramuscularly bid on the first 3 days postpartum to oxytocin and control groups, respectively. The pulsed Doppler ultrasonography is used to measure pulsatility and resistance indices (PI and RI, respectively) of external pudendal artery. Although oxytocin group tended to have relatively higher PI and RI values, significant differences were detected only in PI values of the first and second days postpartum (p<0.001 and p<0.05, respectively) between groups. It has been concluded that oxytocin administration increased the resistance of mammary artery in early postpartum ewes

Serum anti-Mullerian hormone levels during estrus and diestrus in mares

Anti-Mullerian hormone (AMH) is a homodimeric glycoprotin secreted by granulosa cells in postnatal females. AMH plays an important role in follicle recruitment. The aim of the study was to analyse AMH concentrations under the guidance of circulating estradiol and progesterone levels in mares. The study was conducted on 25 non-lactating mares with regular estrous cycles. Blood samples were collected during estrus and diestrus to analyse estradiol, progesterone and AMH concentrations. Estradiol and progesterone concentrations were significantly different (P <0.001) between estrus and diestrus. AMH concentrations in estrus were significantly higher than those in diestrus (P < 0.05). According to the authors' knowledge, this is the first report to suggest that the sexual cycle stage affects AMH concentrations in mares. Further investigations are needed to reveal factors affecting the AMH production and secretion pattern throughout the sexual cycle

B-mode and Doppler Ultrasonographic Assessment of Uterine Involution in Ewes Treated with Two Different Doses of ProstaglandinF2α

Background: Several studies consisted of postmortem evaluations and B-mode ultrasonography have been performed on ovine uterine involution. However, researches with Doppler ultrasonography are very limited in ewes. Doppler ultrasonography is a non-invasive method which provides information about vascular dynamics of the tissues which cannot be examined by B-mode ultrasonography. The aim of the study was to evaluate the effects of two different PGF2α doses on uterine measurements by real time B-mode ultrasonography; and on uterine artery hemodynamics by pulsed-wave Doppler analysis during postpartum uterine involution in ewes.Materials, Methods & Results: The study was conducted with 30 primiparous Kiwircik ewes which lambed singleton without any complication. The ewes were randomly divided into three groups (n= 10 for each group). A single i.m. injection of 125 μg/sheep PGF2α, 75 μg/sheep PGF2α, and 1.0 mL/sheep sterile saline solution were administered to Group 1, 2, and 3, respectively. The day of parturition was considered as the first day of the study. Examinations were performed on days 1, 2, 3, 7, 14, 21 and 28. Diameters of previously gravid horn and caruncles were measured by real time B-mod ultrasonography. Presence of lochia was also noted. Uterine artery pulsatility index (PI), resistance index (RI), systolic/diastolic ratio (S/D) values were measured by pulsed-wave Doppler ultrasonography. The one-way analysis of variance and Duncan’s test were used for statistical analysis. The mean previously gravid horn diameters of ewes were 8.30 ± 0.16 cm and 1.53 ± 0.07 cm on day 1 and day 28, respectively. Previously gravid horn and caruncle diameters had a similar declining pattern in all groups as involution period proceeded. Involution was mostly completed by day 21. More than 50% reduction in uterine size was achieved in prostaglandin administered groups by day 7. Caruncles were not able to be identified after the second week postpartum. Lochia was observed for a longer period in control group. Uterine artery PI and RI showed fluctuations throughout involution period with a similar pattern among groups. S/D values progressively increased until day 14, then showed a decreasing pattern.Discussion: The effects of different PGF2α doses on uterine measurements and uterine artery hemodynamics during postpartum period were compared in ewes for the first time. The uterine size reduction in prostaglandin administered groups suggested that both PGF2α doses were effective in uterine involution. The last observation of lochia in uterine cavity were achieved by day 7 in prostaglandin administered groups, suggesting both PGF2α doses trigger uterine contractions which lead to the removal of uterine content. Automatic measurements by Doppler device were taken in order to provide uniformity and to prevent operator-based bias. The significantly higher uterine artery PI value found in Group 1 on day 1 might suggest the stimulatory effect of PGF2α administration on uterine contractility synergitically with already released endogenous PGF2α. Uterine artery PI and RI showed fluctuations throughout involution period and reached their peak values on day 14. The increasing S/D values up to day 14 indicated increasing diastolic flow, increasing resistance and decreasing blood perfusion in prostaglandin administered groups. Prostaglandin administered groups tended to show higher hemodynamic parameters throughout the study which suggested a vasoconstrictor effect of PGF2α. In conclusion, PGF2α administration on the day of parturition might have constrictor effects both on uterine artery and myometrium which leads to a reduction in uterine blood flow and a rapid decline in uterine size especially during early puerperium even with a reduced dose

B-mode and Doppler Ultrasonographic Assessment of Uterine Involution in Ewes Treated with Two Different Doses of ProstaglandinF(2 alpha)

Background: Several studies consisted of postmortem evaluations and B-mode ultrasonography have been performed on ovine uterine involution. However, researches with Doppler ultrasonography are very limited in ewes. Doppler ultrasonography is a non-invasive method which provides information about vascular dynamics of the tissues which cannot be examined by B-mode ultrasonography. The aim of the study was to evaluate the effects of two different PGF(2 alpha) doses on uterine measurements by real time B-mode ultrasonography; and on uterine artery hemodynamics by pulsed-wave Doppler analysis during postpartum uterine involution in ewes