Reference values for fetal heart rate in cattle in the first trimester of pregnancy

The aim of this study was to create a fetal heart rate (FHR) reference curve for singleton bovine fetuses in the first trimester of gestation and to determine its possible relationship with the outcome of pregnancy. Forty-eight Holstein-Friesian cows with one fetus and five cows with twins were used. Fetal heart beatings were recorded on videotape during transrectal scanning with a 5 and/or 7.5 MHz linear array transducer on a weekly basis between Days 40 and 95 of gestation. FHR was calculated by averaging the results of five counts of the same record by the same observer. For singleton pregnancies, a reference curve was created using the mean, the standard deviation (SD) and the 5th and 95th percentiles. The FHR increased from Days 40–46 (173 beats/min) to Days 61–67 (183 beats/min). After a peak, the FHR decreased slowly until Days 89–95 (175 beats/min), while the SD increased. There was no significant difference between singleton and twin fetuses. in the aborted and lost fetuses in twin gestation due to fetal reduction, both bradycardia and tachycardia were detected compared to the singleton pregnancy reference curve

Effect of exogenous circulating anti-bPL antibodies on bovine placental lactogen measurements in foetal samples

BACKGROUND: The involvement of placental lactogen (PL) in the regulation of foetal growth has been investigated in different species by in vivo immunomodulation techniques. However, when circulating antibodies are present together with the hormone, the procedure for hormonal measurement becomes considerably complex. The aim of this study was the immunoneutralization of bovine placental lactogen (bPL) concentrations in bovine foetal circulation by direct infusion of rabbit anti-bPL purified immunoglobulins (IgG) via a foetal catheter (in vivo study). The ability of a RIA based on guinea pig anti-bPL antiserum, for the measurement of bPL concentrations in samples containing exogenous rabbit anti-bPL immunoglobulins, was also analyzed in in vitro and in vivo conditions. METHODS: Six bovine foetuses were chronic cannulated on the aorta via the medial tarsal artery. Infusion of rabbit anti-bPL IgG was performed during late gestation. Pooled rabbit anti-bPL antisera had a maximal neutralization capacity of 25 microg bPL/mL of immunoglobulin. Interference of rabbit anti-bPL immunoglobulin with radioimmunoassay measurement using guinea pig anti-bPL as primary antibody was first evaluated in vitro. Polyclonal anti-bPL antibodies raised in rabbit were added in foetal sera to produce 100 samples with known antibodies titers (dilutions ranging from 1:2,500 till 1:1,280,000). RESULT(S): Assessment of the interference of rabbit anti-bPL antibody showed that bPL concentrations were significantly lower (P < 0.05) in samples added with dilutions of rabbit antiserum lower than 1:80,000 (one foetus) or 1:10,000 (four foetuses). It was also shown that the recovery of added bPL (12 ng/mL) was markedly reduced in those samples in which exogenous rabbit anti-bPL were added at dilutions lower than 1:20,000. Concentrations of foetal bPL were determined in samples from cannulated foetuses. In foetuses 1 and 6, bPL concentrations remained almost unchanged (<5 ng/mL) during the whole experimental period. In Foetus 3, bPL concentrations decreased immediately after IgG infusion and thereafter, they increased until parturition. CONCLUSION(S): The use of a bPL RIA using a guinea pig anti-bPL as primary antiserum allowed for the measurement of bPL concentrations in foetal plasma in presence of rabbit anti-bPL IgG into the foetal circulation. Long-term foetal catheterization allowed for the study of the influence of direct infusion of anti-bPL IgG on peripheral bPL concentrations in bovine foetuses

A collection of bacterial isolates from the pig intestine reveals functional and taxonomic diversity.

Our knowledge about the gut microbiota of pigs is still scarce, despite the importance of these animals for biomedical research and agriculture. Here, we present a collection of cultured bacteria from the pig gut, including 110 species across 40 families and nine phyla. We provide taxonomic descriptions for 22 novel species and 16 genera. Meta-analysis of 16S rRNA amplicon sequence data and metagenome-assembled genomes reveal prevalent and pig-specific species within Lactobacillus, Streptococcus, Clostridium, Desulfovibrio, Enterococcus, Fusobacterium, and several new genera described in this study. Potentially interesting functions discovered in these organisms include a fucosyltransferase encoded in the genome of the novel species Clostridium porci, and prevalent gene clusters for biosynthesis of sactipeptide-like peptides. Many strains deconjugate primary bile acids in in vitro assays, and a Clostridium scindens strain produces secondary bile acids via dehydroxylation. In addition, cells of the novel species Bullifex porci are coccoidal or spherical under the culture conditions tested, in contrast with the usual helical shape of other members of the family Spirochaetaceae. The strain collection, called 'Pig intestinal bacterial collection' (PiBAC), is publicly available at www.dsmz.de/pibac and opens new avenues for functional studies of the pig gut microbiota

Changes of Acid-Base Variables in Dairy Cows with Chronically Implanted Fetal and Maternal Catheters during Late Gestation and Calving

The objective of the present study was to evaluate the changes in maternal and fetal arterial acid-base variables withdrawn from catheterized dams and fetuses during the last days before and during calving. The average gestation length in nine cows with chronically catheterized fetuses was 285 ± 10 (SD) days. The arterial acid-base variables of a catheterized dam and fetus were very stable during late gestation. Four newborn calves showed small differences between prenatal and postnatal pH values (−0.035). At the same time, pCO2 values started to increase significantly (p = 0.02), indicating a shift towards physiological respiratory acidosis during calving. The partial pressure of oxygen and oxygen saturation values showed some non-significant improvements immediately after birth, while the other acid-base parameters did not differ. The remaining five newborn calves showed a significant decrease in arterial blood pH (p p = 0.01), while pCO2 tended to be higher (p = 0.06), indicating a shift towards physiological respiratory and metabolic acidosis, while the other acid-base parameters hardly differed. It is essential to mention that physiological (n = 2) and mild metabolic acidosis (n = 2) developed gradually in four newborn calves during the second stage of calving, lasting about ≤ 2 h. In contrast, in the remaining newborn calf the physiological metabolic acidosis developed during the last 3 min of birth because immediately before birth, the BE value was 0.4 mmol/L. After birth, it was −5.4 mmol/L. The results indicate that the acid-base variables may start to move gradually in the direction of expressed respiratory and metabolic acidosis only after appearing the amniotic sac and fetal feet in the vulva during the second stage of labor; therefore, it is essential to complete obstetrical assistance in time

Comparison of ultrasonography, bovine pregnancy specific B, and bovine pregnancy-associated glycoprotein 1 test for pregnancy detection in dairy cows

At Days 26 to 58 after AI, 138 Holstein-Friesian dairy cows were repeatedly examined by ultrasonography, using a 7.5 MHz linear-array rectal transducer. The total calving rate was 37.6% (52/138), and late embryonic mortality occurred 8.6% of the cows (12/138). On the days of ultrasound scanning, blood samples were drawn from the jugular vein for measuring the concentration of bovine pregnancy-specific protein B (bPSPB) and bovine pregnancy-associated glycoprotein 1 (bPAG 1). When compared with calving results, there were no significant differences in accurate diagnosis of pregnant cows were found between the 3 methods. However, when recognition of an embryo proper with a beating heart was used as the criterion for positive ultrasonographic diagnosis significantly fewer (P<0.001) pregnant cows were correctly identified than by the other 2 tests. When compared with the noncalving cows, significantly fewer (P<0.001) false positive diagnoses were made by the 2 ultrasonographic tests than by the PSPB and bPAG 1 tests, while significantly fewer (P<0.001) false positive diagnoses were made by the bPSPB test than by the bPAG 1 test. The accuracy of detecting nonpregnant animals by both protein tests was limited by the relatively long half-life of these proteins after calving and by early embryonic mortality.Grant number OTKAT01690

Development of a surgical technique for long-term catheterisation of bovine fetuses

The aim of this study was to further develop and extensively describe a surgical technique in order to realise long-term fetal blood sampling in the bovine species. Eleven Holstein-Friesian 6-to 8-month pregnant cows (4-10 years old) were used for this study. Gestational age on the day of surgery varied from approximately 180 days (n = 1) to 240 days (minimum: 232 days, maximum 252 days; n = 10). The fetal medial tarsal artery was catheterised in pregnant cows with a polyvinyl catheter in dorsal recumbency under general anaesthesia. Although 5 out of 11 operations (45.5%) performed between 232 and 252 days of gestation were lost due to different causes mainly associated with peritonitis and septicaemia, the mean interval between operations and calvings was 42.5 days (between 27 and 95 days). It is important to emphasise that a well-trained surgical team is needed for bovine fetal cannulation in order to be able to decrease the risk factors during the operations. Due to the fact that after 5 unsuccessful cases none of the pregnancies were lost, this skill can be reached, and our technique can enable bovine fetal blood sampling for long-term endocrinological and physiological investigations before and during parturition

The monitoring of bovine pregnancies derived from transfer of in vitro produced embryos

Both an increased rate of embryonic, foetal and perinatal losses, and the occurrence of deviations in foetal and placental development are associated with bovine pregnancies obtained from in vitro produced embryos. This thus requires for a more accurate and frequent monitoring of foetal and maternal functions during pregnancies. Such approaches will enable to establish the period during which these losses and deviations in development occur and to plan possible clinical interventions. This paper reviews some recent data on return rates, late embryonic and foetal losses in recipients after the transfer of either MOET, IVF or nuclear transfer embryos. Special attention is paid to the diagnostic value of measurements of pregnancy specific/associated proteins and progesterone in maternal plasma. Possibilities to measure foetal body sizes, size of placentomes and foetal heart rate by means of transrectal or transabdominal ultrasonography are illustrated with data from the literature and with recent results from our own large field study with MOET, IVP-co-culture and IVP-SOF embryos

A formação de professores em perspectivas internacionais: estudo comparado entre modelos europeus e brasileiro

During early embryonic development, pig and chicken embryos share striking morphological similarities. In the present study, the timing and location of expression of mRNA for goosecoid (gsc), a gene classically expressed in the nodal region of developing embryos, was examined and compared in preprimitive streak and gastrulating pig and chicken embryos. The expression of gsc appeared first in the hypoblast and second in the hypoblast of pig and chicken embryos. Because gsc expression in these tissues was not symmetrical, gsc appears to be a useful marker for the onset of embryonic polarity. During gastrulation in both species, gsc expression became confined to cells in and around the node, in the epiblast and mesoderm layers. The only significant species-related difference in the distribution of gsc expression at these stages of development was the presence of gsc expression in the gut endoderm of chicken but not pig embryos. Certainly, our results suggest that the molecular mechanisms that control anterior–posterior development in different classes of vertebrates are remarkably similar. In addition, we were able to demonstrate that the pattern of gsc expression appears to provide a more sensitive and accurate means of determining the developmental stage of early porcine embryos than the more commonly used trophoblast or embryoblast size. Using gsc expression and accompanying embryo morphometric changes, we were able to develop a four-point scale that may offer a more accurate means of quantifying early embryo development in pigs