Ultrasound fetal measurements and pregnancy associated glycoprotein secretion in early pregnancy in cattle recipients carrying somatic clones

It has been shown in several mammalian species that during pregnancy, trophoblast cells express a range of pregnancy-associated glycoproteins (PAG). The presence of PAG in the maternal serum of cows may serve as an indicator of pregnancy from day 28 after AI onward. The present study addresses (1) conversion of an existing PAG-RIA to a competitive double antibody ELISA using a polyclonal anti-bPAG-IgG and an anti-rabbit-IgG raised in sheep for coating and (2) application of newly established ELISA to test its suitability for pregnancy detection by measuring PAG in serum or milk. The intraassay coefficients of variation (CV) for the PAG-ELISA were 2-14% for serum and 10-12% for milk; the corresponding interassay CVs were 8-22% and 12-22%, respectively. Pregnancy-associated glycoprotein profiles established in milk and serum of 12 pregnant cows showed a characteristic pattern with measurable amounts from approximately day 20 onwards in serum and from day 60 onwards in milk. In a field trial, serum PAG was determined in 397 cows sampled between 20 and 50 days after insemination. The outcome was that, pregnancy could reliably be diagnosed from day 28 onwards in serum and from day 150 onwards in milk. In conclusion, it may be stated that the established ELISA provides an efficient and reliable means of pregnancy diagnosis that will, in our judgement, gain in popularity with cattle breeding. The ELISA proved to be an adequate and efficient way of measuring PAG in maternal serum or milk and will be a useful means of pregnancy detection in cows.

Establishment of an ELISA for measuring bovine pregnancy-associated glycoprotein in serum or milk and its application for early pregnancy detection.

Changes in serum pregnancy-associated glycoprotein, pregnancy-specific protein B, and progesterone concentrations before and after induction of pregnancy loss in lactating dairy cows

The aim of this analysis was to determine whether pregnancy loss (PL) after embryo transfer (ET) in cattle was related to maternal progesterone (P4) concentrations during and shortly after ET, and maternal bovine pregnancy-associated glycoprotein-1 (bPAG-1) concentrations in plasma at days 25–35 of gestation. Embryos (n = 260) were produced either in vivo after superovulation (n = 115), or in vitro from oocytes (obtained with ovum pick-up) in co-culture (n = 44) or cultured in a synthetic medium (n = 101). Overall, PL was 56.9% (148) and no significant differences occurred in calving rate among the three embryo production groups. There was no difference in P4 concentrations on days 7–14 of gestation in the three groups, nor between ongoing and interrupted pregnancies. Between days 25 and 35 of pregnancy, bPAG-1 concentrations were unaffected by embryo production, but in cattle that had PL between days 26 and 120, four bPAG-1 profiles could be detected. Between days 25 and 32, bPAG-1 concentrations were influenced by PL, and concentrations were significantly lower in animals in which PL occurred between days 26 and 120 than in those animals that aborted later or calved at term. Early P4 concentrations suggested that maternal luteal factors were not responsible for PL which appeared to be caused by impaired conceptus development (regardless of embryo type) as reflected by low maternal bPAG-1 concentrations prior to embryonic death.

Characterisation of pregnancy losses after embryo transfer by measuring plasma progesterone and bovine pregnancy-associated glycoprotein-1 concentrations

Aglepristone: A review on its clinical use in animals

Ultrasonographic appearance of the conceptus, fetal heart rate and profiles of pregnancy-associated glycoproteins (PAG) and prostaglandin F2α-metabolite (PGF2α-metabolite) after induction of fetal death with aglepristone during early gestation in cattle

This article explores the current and expected direction of education in reproduction at the Faculty of Veterinary Medicine of Utrecht University. The current reproductive course in the Bachelor's programme is described. Based on the yearly routine course evaluation, changes have been started and continue to be implemented, and the educational ideas behind it are defined. Interactive e-learning modules that combine knowledge clips, animations, and quizzes have been developed. For the practical classes, e-modules with instructional videos have been paired to the written material. Using these new tools during self-study, students have to prepare for the necessary face-to-face classes that contain more in-depth discussions and practical training. In the second part, the author describes his expectations for further educational development. The growth of effective self-study using e-learning, besides traditional textbooks, before more in-depth face-to-face classes is likely to occur. With the growth of modern possibilities, such as the haptic technique and virtual reality, a better preparation in laboratory skills before practical training with animals is expected. In the author's opinion, despite all new learning methods and material, small group, face-to-face lectures, and practical classes with animals or animal material remain absolutely necessary. This article concludes with some lessons learned during the current adaptation of the course.

A personal view on basic education in reproduction: Where are we now and where are we going?

Objective To describe perioperative management, surgical procedure, and outcome in mares with third-degree perineal lacerations (TDPL) treated with a single-stage repair, the Utrecht repair method (URM). Study design Retrospective study. Animals Twenty mares with TDPL. Methods Medical records of mares with TDPL reconstructed with a URM were reviewed for perioperative management; surgical outcome; and postoperative fertility, athletic performance, and complications. Results Mares ranged in age from 3.5 to 11 years. Long-term follow-up was available for 13 mares. Mean duration of follow-up was 9 years (median, 9.5; range, 2-215 months (17.9 years)). Standardized perioperative fasting and postoperative refeeding protocols were used. Only five mares received supportive gastric medication. Reconstruction of the rectovestibular shelf was successful in 18 of 20 mares. Two of 20 mares developed a small rectovestibular fistula after the initial repair, which was successfully repaired with a second surgery. Other postoperative complications were observed in 13 mares and consisted of mild postanesthetic myositis, facial nerve paralysis, esophageal obstruction, rectal obstipation, partial perineal dehiscence, and rectal or vestibular wind-sucking. Six of seven mares that were subsequently bred became pregnant. One mare was successfully used for embryo recovery, and five of six mares foaled without recurrence of a TDPL. Nine of 13 mares were used for riding at various levels. Conclusion The alternative single-stage reconstruction for TDPL was successful in 18 of 20 mares after a single surgery. No major complications related directly to the technique were noted. Clinical significance The URM is a valid alternative surgical technique for repairing TDPL in mares.

F. Herman Jonker

Papers

Ultrasonographic appearance of the conceptus, fetal heart rate and profiles of pregnancy-associated glycoproteins (PAG) and prostaglandin F2α-metabolite (PGF2α-metabolite) after induction of fetal death with aglepristone during early gestation in cattle

A personal view on basic education in reproduction: Where are we now and where are we going?

Single-stage reconstruction of third-degree perineal lacerations in horses under general anesthesia: Utrecht repair method.