Transabdominal ultrasonography has been popularly used in animal reproduction for the assessment of pregnancy status and foetal viability where as transvaginal method for pregnancy diagnosis is rarely used for pregnancy diagnosis in goats. The study was conducted in 74 Attappady Black goats from Government Goat Farm, Attappady and Livestock Research Station, Thiruvizhamkunnu to evaluate the accuracy of trans-vaginal methods and to identify the fetal characteristics from day 20 to 75. Transvaginal ultrasonographic examination was performed using endocavity transducer with frequency of 6.5 to 8 MHz. Observations were made in all the pregnant does at three different stages of pregnancy i.e., 20-35 days, 35-55 days and 55-75 days. Does were diagnosed as pregnant from the observation of gestational sac, embryo or foetus, embryonic or foetal heartbeat, placentomes or foetal skeleton. Sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy along gestation period were 98.03, 92.3, 96.15, 96 and 95.62%, respectively. It is concluded from the present study that transvaginal ultrasonography can be used for herd pregnancy diagnosis at early stages from day 20 to 45 of pregnancy diagnosis in goats.

Anatomical and histological changes were studied in the dorsal, ventral, third and splenic lobes of the pancreas of the chicken embryos (8 days of incubation, 10 days of incubation to hatching). From 13 days of incubation, all four pancreatic lobes, namely, dorsal, ventral, third and splenic lobes were observed. Histologically, the pancreas of 10-14 days of incubation were consisted of mesenchymal tissue, exocrine acini and pancreatic islets. But mesenchymal tissues were disappeared from 15 days of incubation. The pancreatic ducts were observed from 14 days of incubation. The dark and light typed pancreatic islets were observed in splenic lobe from 13 days of incubation, in the third lobe from 11 days of incubation, and in the dorsall lobe from 13 days of incubation. But no dark typed islets were observed in the ventral lobes.

We investigated the feasibility of cryopreservation of zebrafish (Danio rerio) blastomeres and primordial germ cells (PGCs) by rapid freezing of dechorionated whole embryos at the blastula, gastrula and segmentation stages. Initially we examined the glass-forming properties and embryo toxicities of 5 cryoprotectants: methanol (MeOH), ethylene glycol (EG), dimethyl sulfoxide (DMSO), propylene glycol (PG), and 1,3-butylene glycol (1,3-BG). Embryos at the blastula and gastrula stages had high sensitivities to cryoprotectant toxicities and were fragile against mechanical damage. Thus the segmentation stage embryos, the PGCs of which were visualized by injecting green fluorescence protein-nos1 3'UTR mRNA, were frozen using solutions containing each cryoprotectant at 6 M (first trial) and 2 types of cryoprotectants at 3 M each (second trial). In the first trial, live PGCs were recovered from most of the embryos frozen with EG (about 2 cells/embryo); however, a few embryos had live PGCs when embryos were frozen with other cryoprotectants. In the second trial; a mixture of EG + PG better preserved the viability of PGCs in frozen embryos. Live PGCs were recovered from all embryos frozen with EG + PG (about 3 cells/embryo), and the survival rate of PGCs was estimated to be about 25% based on the number of live PGCs in fresh embryos (about 12 cells/embryo). The present study indicates that we can utilize rapid freezing of dechorionated whole embryos at the segmentation stage for the cryopreservation of PGCs.

The in vitro differentiative potential of mouse parthenogenetic (PG) embryonic stem (PGES) cells were investigated in the formation of embryoid bodies (EBs). EBs derived from PGES cells retarded in growth and showed restricted differentiation compared to their fertilized counterpart. In chimeric EBs from the aggregation of PGES and fertilized ES cells, morphological examination revealed that PGES cells were reduced in their population and distributed in endodermal layer as culture periods proceeded. These findings were comparable to those in aggregation chimeras of fertilized and PG embryos, and suggest that the differentiation of PGES cells in vitro is restricted in the formation of EBs

The CKH-Jsr (jumbled spine and ribs) mouse was found as a spontaneous mutant with malformation of vertebrae, that is, a short trunk and kinky tail. We examined Lunatic Fringe (Lfng and Uncx4. 1 expression in the presomitic mesoderm (PSM) and somites of Jsr-mutant (CKH-Jsr/+) embryos to elucidate pathogenesis of the Jsr mutation. Expression pattern of Lfng in the PSM of Jsr-mutant embryos was similar to that of the normal (C57BL/6) embryos. However, expression pattern of Uncx4. 1 in the somites of Jsr-mutant embryos was impaired to be irregular and mosaic, suggesting that the anterior-posterior (A-P) polarity is disordered in the Jsr mutant. These results indicate that the Jsr mutation disrupts the A-P polarity of somites during the somitogenesis without altering Lfng expression pattern in the PSM.

Effects of oxygen (O2) tension in the gas atmosphere during in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) on the efficiency of in vitro production of mouse embryos were examined. Mouse oocytes recovered from large antral follicles were subjected to IVM in Waymouth medium for 15, 16 and 17 hr under 5 or 20% O2 and then subjected to IVF and IVC under 5 or 20% O2 tension. Lowering the O2 tension in the gas atmosphere for IVM from 20 to 5% improved the cleavage rate after IVF when the oocytes were subjected to IVM for 15 hr; however, no improvement in the cleavage rate was observed when the culture period for IVM was extended to 16 and 17 hr. Lowering the O2 tension to 5% for IVM and IVC improved the development of the cleaved oocytes to the blastocyst stage, regardless of the culture period for IVM. However, the O2 tension for IVF had no remarkable effect on the subsequent embryonic development. These results demonstrate that 5% O2 is superior to 20% O2 for IVM and IVC, and suggest that 20% O2 for IVM may delay oocyte maturation and/or the acquisition of fertilizability and impair the developmental competence of oocytes.