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.

Objective: To examine in mice the acute effects of epigallocatechin gallate (EGCG), a green tea bioactive polyphenol on substrate metabolism with focus on the fate of dietary lipids. Methods: Male C57BL/6 mice were fed high-fat diets supplemented with EGCG extracted from green tea (TEAVIGO, DSM Nutritional Products Ltd, Basel, Switzerland) at different dosages up to 1% (w/w). Effects of EGCG on body composition (quantitative magnetic resonance), food intake and digestibility, oxidation and incorporation of exogenous lipids (stable isotope techniques:13 C-labeled palmitate and diet supplemented with corn oil as a natural source of 13 C-enriched lipids) as well as gene expression (quantitative real-time PCR) in liver and intestinal mucosa were investigated. Results: Short-term supplementation (4-7 days) of dietary EGCG increased energy excretion, while food and energy intake were not affected. Fecal energy loss was accompanied by increased fat and nitrogen excretion. EGCG decreased post-prandial triglyceride and glycogen content in liver, increased oxidation of dietary lipids and decreased incorporation of dietary 13C-enriched lipids into fat tissues, liver and skeletal muscle. EGCG dose dependently reversed high-fat diet-induced effects on intestinal substrate transporters (CD36, FATP4 and SGLT1) and downregulated lipogenesis-related genes (ACC, FAS and SCD1) in liver in the post-prandial state. Conclusions: Anti-obesity effects of EGCG can be explained by a decreased food digestibility affecting substrate metabolism of intestinal mucosa and liver, leading to increased post-prandial fat oxidation and reduced incorporation of dietary lipids into tissues.

The predictive value of uterine artery Doppler for adverse pregnancy outcome in a low-risk population is of limited diagnostic value. Performing uterine artery Doppler studies at 23-26 weeks' gestation instead of 19-22 weeks' gestation increases the predictive value for adverse pregnancy outcomes.

The reference ranges and calculated velocities established in this study may be utilized in studies dealing with the role of ductus venosus and inferior vena cava blood flow in fetuses with chromosomal abnormalities or congenital heart disease as well as hypoxic conditions. We speculate, that the reduction in PVIV and PIV with advancing gestational age may reflect a decrease in cardiac afterload as a result of maturation of diastolic ventricular function.

Binucleate trophoblast giant cells (BNC) in the bovine placenta produce glycoproteins, which are delivered into the mother after fusion of BNC with uterine epithelial cells. During most time of pregnancy, BNC produce pregnancy-associated glycoproteins (PAGs) and prolactin-related protein-I (PRP-I) with asparagine-linked lactosamine-type glycans terminating with N-acetyl-galactosamine. We show by lectin histochemistry that terminal N-acetyl-galactosamine (detected by Dolichos biflorus agglutinin, DBA) in placentomal BNC is greatly reduced prior to parturition, while lactosamine-type N-glycans (detected by Phaseolus vulgaris leucoagglutinin, PHA-L) remain unaltered. The change in DBA-staining showed no statistically significant differences between placentomes of cows with and without retention of fetal membranes. Western blots revealed that, at parturition the apparent molecular mass of PAGs and PRP-I is 1-2 kDa lower than in late pregnancy. These changes are due to alterations of asparagine-linked glycans, since the molecular weight of the peptide backbones after enzymatical release of asparagine-linked glycans is identical at late pregnancy and parturition. Lectin western blots showed a reduction of terminal N-acetyl-galactosamine on PAGs at parturition. A lectin sandwich-ELISA was used to differentiate DBA-and PHA-L-binding PAGs in sera of pregnant and non-pregnant cows. The values for DBA-binding PAGs at parturition were not significantly different from non-pregnancy, while the values for PHA-L-binding PAGs were significantly higher at parturition. The peripartal changes of PAG-and PRP-I-glycosylation could alter functional properties of these proteins and might therefore be considered for functional studies. The differentiation of PAG glycoforms in maternal serum could be valuable for a further optimization of PAG-based pregnancy diagnosis in cattle. Reproduction (2006) 132 791-798