Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias

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16 t h International Congress on Animal Reproduction 26 Workshop Abstracts Workshop 18 - Pregnancy, fetal well-being and the periparturient dam Moderator: Marcel A. M. Taverne (The Netherlands) WS18-1 Assessment of fetal well-being during bovine and equine gestations resulting from in vivo and in vitro produced embryos Chavatte-Palmer, P INRA, UMR 1198; ENVA; CNRS, FRE 2857, Biologie du Développement et Reproduction, Jouy en Josas, F-78350, France Pregnant dams need to be monitored in order to precociously diagnose any pathological process and start treatment. Pregnancies established after natural breeding or artificial insemination may not require specific monitoring if the dam is reproductively sound and in absence of maternal pathology (i.e. colics in horses). In contrast, in vitro produced embryos, and particularly cloned embryos, have been associated with severe placental abnormalities and fetal losses, requiring regular assessment of the health of both the recipient and the fetus. In terms of imaging technologies, rectal and transabdominal ultrasound scanning have been used for a long time in the horse to assess fetal growth and activity and evaluate placental health (mainly through the measurement of the utero-placental thickness) throughout pregnancy. Transabdominal ultrasound has also been used successfully in cattle to diagnose the Large Offspring Syndrome (increased fetal size, placental edema, abnormal placentome structures) before clinical signs are prominent and maternal welfare is affected. Transrectal doppler sonography of the uterine artery can also be performed to evaluate uterine blood flow both in the mare and the cow and will provide helpful information on placental perfusion. More recently developed methods, like 3D Doppler scanning, are being evaluated for visualizing the placenta in ruminants, but the use of Magnetic Resonance Imaging is precluded both because of the price and the size of the animals. Ultrasound guided amniocentesis and allantoidocentesis have been performed both in cattle and horses but remain so far too risky for routine use, especially if repeated. It would be worth, however, developing safe procedures to be used in practice as this is a simple technique providing potentially very useful clinical information. Finally, placental biopsies can be performed in cattle but may not provide significant information on fetal well-being. Most useful maternal blood markers for fetal well-being include estrone sulfate and progestagens in the horse. In cattle, the maternal plasma concentration of placental Pregnancy Associated Glycoproteins (PAG) is routinely used for pregnancy diagnosis but may also be helpful in detecting animals likely to develop the Large Offspring Syndrome. Finally, the diagnostic and prognostic interest of other molecules, such has the acute phase protein Serum Amyloid A (SAA) must yet be explored. WS18-2 Monitoring of the bovine fetus during and shortly after birth Bleul, U Department of Food Animals, Clinic of Reproductive Medicine, Switzerland Approximately 3% of all bovine fetuses die during or shortly after birth. In the majority of cases the reason for this peripartal mortality is dystocia. This bears the risk of fetal damage caused by hypoxia, hypercapnia and acidosis. In the field methods for monitoring the well-being of the fetus during parturition are almost lacking. The evaluation of vitality is based mainly on reflexes, meconium staining of the fetus and the amniotic fluid or the detection of a heart beat in the fetus, but they do not allow an accurate estimate of fetal acidosis. In the last years new methods were described which may help to recognize fetal distress. In human medicine, cardiotocography measurement is the standard procedure for fetal monitoring intrapartum and has been evaluated in experimental studies with bovine fetuses. Cardiotocography measures the fetal heart beat and the intrauterine pressure continuously and the fetal heart rate correlates well with the neonatal outcome. Further methods were recently described, which measure the fetal oxygen saturation or blood gas parameters. Oxygen saturation was measured using pulsoximetry by placing an oxygen sensor in the mouth against the mucosa of the hard palate of the fetus. Although postnatal acidosis can be predicted by continuously measuring the oxygen saturation of the fetus intrapartum, technical modifications are required to improve its usefulness. In experimental studies, bovine fetal blood has been collected transvaginally from the umbilical vessels, by centesis or catheterization of the carpal or digital veins. Capillary blood has been collected from the dorsolateral aspect of the distal pastern when the calf’s forelimbs protrude from the vulva. Blood gas values during stage II labor were suitable in order to diagnose fetal asphyxia and selected parameters showed high correlations with the level of postnatal acidosis. Determination of blood gas values of venous blood is an established method for detecting the metabolic component of the mixed metabolic-respiratory acidosis in calves immediately after birth. Because the respiratory component of acidosis is difficult to determine with venous blood, collecting arterial blood is a more reliable method for evaluating pulmonary function by determination of the partial pressure of carbon dioxide and oxygen of arterial blood. Various methods of monitoring the calf during and after birth have been established which may reduce fetal mortality by indicating the right time for an obstetrical intervention, or the necessity of a therapeutic intervention in the newborn calf. WS18-3 The sow and her piglets during the farrowing process Van Dijk, J Faculty of Veterinary Medicine, Utrecht University, The Netherlands Perinatal asphyxia is an important cause of perinatal mortality and reduced viability and vitality of newborn piglets. The occurrence of perinatal asphyxia is clearly associated with the farrowing process. Consequently, several factors affecting the duration of the expulsive stage of farrowing (DF) have been identified. Whereas the effect of parity is controversial, breed significantly affects DF and in this respect the Meishan holds a rather unique position as the number of stillbirths is not related to DF. Furthermore, a decreased gestational length and increased number of liveborn and / or stillborn piglets result, independently of each other, in a significant increased DF. To lower the risk for perinatal asphyxia at birth, attempts have been made to reduce the DF by administration of oxytocin. However, despite a reduction of DF, increasing numbers of intrapartum stillbirths with ruptured umbilical cords and severe meconium staining at birth are observed. Regarding factors affecting individual birth intervals between piglets (BI), it has been shown that higher birth weights, posteriorly presented piglets and stillborn piglets are associated with increased BI. Besides, a curvilinear relationship exists between rank (relative position in the birth order) and individual birth intervals and breed significantly affects this relationship. Several of the factors affecting BI are also shown to affect acid-base balance values in umbilical artery blood samples of liveborn piglets at birth. Piglets born with ruptured umbilical cords show significantly lower pH values and a tendency for higher pCO2 values at birth. Interestingly, decreased birth weights are associated with a slightly more severe metabolic acidosis at birth. Furthermore, posterior presentation at birth, increasing cumulative birth intervals and an increasing rank result in a more pronounced mixed respiratory-metabolic acidosis at birth. The degree of acidosis that gradually develops during the expulsive stage of farrowing is not as severe as observed in newborn, highly asphyxiated piglets at birth. Consequently, it has been stated that traction, occlusion or rupture of the umbilical cord is an inevitable factor in the evolvement of birth asphyxia and concomitant mortality and reduced viability at birth. However, a model of umbilical cord clamping (average duration of cord clamping: 7 minutes) in late pregnant sows suggests an additional role of cumulative uterine contractions, occurring during the expulsive stage of farrowing, in the evolvement of a more or less severe degree of birth asphyxia.
16 t h International Congress on Animal Reproduction Poster Reviewers 27 POSTER REVIEWERS Local Organising Committee wishes to express its sincere gratitude to all poster abstracts reviewers for their willingness to act as poster abstract reviewer during the poster evaluation process. Csaba BAJCSY Agnes BALI PAPP Orsolya BALOGH Judit BARNA Szilard BODO Tamas CSAKI Sandor CSEH Andras DINNYES Istvan EGERSZEGI Vera FAIGL Hedvig FEBEL Ferenc FLINK Jozsef FOLDI Gyorgy GABOR Elen GOCZA Judit JUHASZ Gabor KELEMERI Monika KERESZTES Fruzsina KISS-TOTH Andras KOVACS Karoly MAGYAR Judit MENYHERT Miklos MEZES Peter NAGY Szabolcs NAGY Gabriella NOVOTNI DANKO Anna PECSI Istvan PENTEK Zsuzsanna POLGAR Csaba PRIBENSZKY Angella PROHACZIK Jozsef RATKY Laszlo SOLTI Zsuzsanna SZOKE Julianna THUROCZY Barbara VEGI Laszlo WEKERLE Zoltan ZOMBORSZKY Attila ZSOLNAY
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Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias

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