Remodelling of the bovine placenta: Comprehensive morphological and histomorphological characterization at the late embryonic and early accelerated fetal growth stages

Asymmetric growth-limiting development of the female conceptus

Introduction

Sex differences in prenatal growth may contribute to sex-dependent programming effects on postnatal phenotype.

Methods

We integrated for the first time phenotypic, histomorphological, clinico-chemical, endocrine and gene expression analyses in a single species, the bovine conceptus at mid-gestation.

Results

We demonstrate that by mid-gestation, before the onset of accelerated growth, the female conceptus displays asymmetric lower growth compared to males. Female fetuses were smaller with lower ponderal index and organ weights than males. However, their brain:body weight, brain:liver weight and heart:body weight ratios were higher than in males, indicating brain and heart 'sparing'. The female placenta weighed less and had lower volumes of trophoblast and fetal connective tissue than the male placenta. Female umbilical cord vessel diameters were smaller, and female-specific relationships of body weight and brain:liver weight ratios with cord vessel diameters indicated that the umbilico-placental vascular system creates a growth-limiting environment where blood flow is redistributed to protect brain and heart growth. Clinico-chemical indicators of liver perfusion support this female-specific growth-limiting phenotype, while lower insulin-like growth factor 2 (IGF2) gene expression in brain and heart, and lower circulating IGF2, implicate female-specific modulation of key endocrine mediators by nutrient supply.

Conclusion

This mode of female development may increase resilience to environmental perturbations in utero and contribute to sex-bias in programming outcomes including susceptibility to non-communicable diseases.

ALYE, M. ALHT. Clinical and Ultrasonic Study for Detection of Pregnancy in Iraqi Buffaloes

The present study was conducted on 10 Iraqi pregnant buffaloes aged between 3-6 years at Al-Qasim district- Babylon province, Iraq from December 2018 to December 2019. Those animals diagnosed by rectal palpation and ultrasonography technique to estimate the reproduction status. The results of this study reported wandering of ovum in 10% of animals (1/10). While ultrasonography characterized by increasing placentomes measurement gradually with development of gestation, and the placentomes recorded 8.32±2.46 mm, 13.27±3.25 mm, 18.37±5.34 mm, 23.25±8.63 mm and 28.2±6.87 mm in the 2nd , 3rd, 4th, 5th and 6th month, respectively. Also the total size was recorded by the crown rump length (CRL), which was 0.77±0.05 cm, 5.81±2.54 cm and 14.09±0.73 cm in the 1st, 2nd, and 3rd month, respectively. The heart beat and embryonic vesicle during the 1st and 2nd month were detectable by ultrasonography. In conclusions in the present study, rectal palpation and ultrasonography technique represented one of the most important methods to estimate the gestation period in different stages.

Patterns of protein glycosylation in bovine placentomes as a function of gestational age and in retained versus non-retained placenta

The formation of placenta at the beginning of pregnancy and its separation at parturition require not only deep remodelling of extracellular matrix, which mainly consists of proteins conjugated with sugar moieties, but also the cooperation with cells from both maternal and foetal parts of placenta. The aim of the study was to compare the patterns of selected conjugated proteins with sugar moieties between pregnant and term placenta as well as between released and retained placenta in cows. Placental samples from healthy pregnant cows (3-5 months of pregnancy) were collected at a slaughterhouse (n = 6), and parturient samples were collected during caesarean section at term and retrospectively divided into retained (n = 6) and released (n = 6). The pattern of selected sugar moieties conjugated with proteins was detected by use of lectin blotting with Phaseolus Vulgaris leucoagglutinin, Maackia Amurensis and Sambucus Nigra (Elderberry). The comparison and analysis of obtained band patterns showed differences between their number, molecular weight and abundance related to the intensity of staining. Samples from 3 to 4 months showed similarities, while at the 5th month, clear differences were visible in all 3 lectins, which were used in this study. Samples from retained/released placenta expressed significant differences in PHA-L and SNA pattern in the foetal part. Obtained results indicate that the development of placenta related to extracellular matrix and accompanying cells from both sides of placenta shows dynamic changes during pregnancy. Moreover, in the case of animals with the retention of foetal membranes the patterns of proteins conjugated with sugar moieties are altered, suggesting that the changes in extracellular matrix metabolism can be involved in the attachment and detachment of the placenta in cows.