Post-ovulation Period Research Articles

Study the life aspects of Eriasinsulana Boisd on some of the marshmallow family crops

Based on the importance of cotton crops Gossypium spp., Abelmoschus esculentus and Hibiscus sabdrriffa in Iraq, and because of damage caused by Eriasinsulana boisd cotton worm for these crops, Life data that helps to explain the persistence of this insect as a pest threatening the marshmallow family crops was studied and the main points for the development of effective control programs against it.The results of the laboratory study showed that all the life aspects of the insect were affected during the breeding of different plant families (cotton, okra, hibiscus). The shorter duration of larvae development was 16.27 days and the mean weight was 0.28 g when it was raised on the hibiscus plant and its length was 22.35 days and the highest rate was 0.35 g (18.42 days) and the average weight (0.32 g) on the okra. The highest survival rate was 57% for cotton, while the lowest for the hibiscus plant was 42%. The study showed that the host had an effect on the average period of development of pupa and adult females, with the highest rate of 12.35 and 55.17 days on cotton and the lowest rate of 10.75 and 31.37 days on the hibiscus, respectively. 0.31 and 0.27 g respectively on cotton, while 0.27 and 0.21 g respectively fell on the hibiscus. In terms of the average pre-laying period, the highest rate was 6.24 days on the hibiscus plant, corresponding to 3.89 days on cotton and 5.21 days on the okra, The longest period of laying the eggs was 42.12 days on the cotton, while at least 17.93 days on the hibiscus. The adult insect had the largest number of eggs fed on cotton (75.16 eggs / female) while the lowest number when feeding on the hibiscus (43.3) eggs / female. The results of the study showed that the highest rate of post-ovulation period for the female insect was 3.25 days on the hibiscus and decreased to the lowest rate (2.00 days) on the cotton.It is concluded that the growth and development of the insect was optimal for feeding on cotton.

The porcine sperm reservoir in relation to the function of hyaluronan.

The oviduct plays a role in successful animal reproduction not only in spermatozoa and ova transport to the fertilization site but also by affording a microenvironment for fertilization and early embryonic development. The sperm reservoir (SR) is restricted in the uterotubal junction (UTJ) and caudal isthmus. Billions of porcine spermatozoa are distributed to the female reproductive tract during/after insemination, and small amounts of them are stored for about 36–40 hours in the SR, which maintains sperm viability in the pre-ovulation period through its surface epithelium and production of fluid. The SR regulates the release of spermatozoa so that only a small population moves towards the fertilization site (ampulla) to decrease polyspermy. This review attempts to provide information about the structure and function of the porcine SR, its intraluminal content (hyaluronan, HA), and the influences of HA on porcine spermatozoa in vivo. In pigs, the spermatozoa are stored in a mucous-like fluid within the UTJ and caudal isthmus in the pre-ovulation period. The oviduct fluid contains sulfated glycosaminoglycans (GAGs) and non-sulfated GAGs, i.e., HA. It is interesting to note that HA is synthesized by hyaluronan synthase-3 (HAS-3), and its receptor, CD44, is found in the epithelium of the porcine SR site. Additionally, sperm capacitation does not occur in vivo in the SR during the pre- and peri-ovulation periods, but spermatozoa in the SR will attempt to capacitate if exposed to bicarbonate. However, capacitation in the SR will rise in the post-ovulation period, indicating the role of HA in modulating sperm capacitation after ovulation. All data support the understanding that the porcine SR ensures the viability of fertile spermatozoa and maintains the non-capacitated status during the pre-ovulation period. This basic knowledge about the SR is believed to be useful to advance sperm preparation procedures for in vitro fertilization (IVF) and improve the preservation process of porcine semen.

Expression of nuclear progesterone receptor and progesterone receptor membrane components 1 and 2 in the oviduct of cyclic and pregnant cows during the post-ovulation period

BackgroundProgesterone (P4) may modulate oviductal functions to promote early embryo development in cattle. In addition to its nuclear receptor (PR), P4 may mediate its actions through P4 receptor membrane component 1 (PGRMC1) and its relative, PGRMC2. Two successive experiments were undertaken to characterise the expression of PR, PGRMC1 and PGRMC2 in the bovine oviduct during the post-ovulation period, and to relate their expression to the presence of an embryo, the proximity of the CL and to the region of the oviduct.MethodsIn the first experiment (Exp. I), whole oviduct sections were collected from Holstein cows at Day 1.5, Day 4 and Day 5 post-ovulation (n = 2 cows per stage). The expression of PR, PGRMC1 and PGRMC2 was studied in the ampulla and isthmus by RT-PCR, western-blot and immunohistochemistry. In Exp. II, oviduct epithelial cells were collected from cyclic and pregnant Charolais cows (n = 4 cows per status) at Day 3.5 post-ovulation and mRNA expression of PR, PGRMC1 and PGRMC2 was examined in the ampulla and isthmus by real-time quantitative PCR.ResultsIn Exp. I, PR, PGRMC1 and PGRMC2 were expressed in all oviduct samples. PGRMC1 was mainly localised in the luminal epithelium whereas PR and PGRMC2 were localised in the epithelium as well as in the muscle and stroma layers of the oviduct. The expression was primarily nuclear for PR, primarily cytoplasmic for PGRMC1 and both nuclear and cytoplasmic for PGRMC2. In Exp. II, mRNA levels for PR, PGRMC1 and PGRMC2 were not affected by either the pregnancy status or the side relative to the CL. However, the expression of PR and PGRMC2 varied significantly with the region of the oviduct: PR was more highly expressed in the isthmus whereas PGRMC2 was more highly expressed in the ampulla.ConclusionsThis is the first evidence of PGRMC2 expression in the bovine oviduct. Our findings suggest that P4 regulates the functions of the bovine oviduct in a region-specific manner and through both classical and non classical pathways during the post-ovulation period.

Relationship between Plasma Progesterone Concentration and Number of Conceptuses and Their Growth in Superovulated Cattle

Elevated concentrations of circulating progesterone (P₄) in the immediate post-ovulation period are associated with advancement of conceptus elongation in cattle. Superovulated (SOV) cattle have not only elevated plasma P₄ concentrations but also multiple embryos in the uterus because of the formation of multiple corpora lutea. We examined the relationship between plasma P₄ concentration and uterine glucose level in the immediate post-ovulation period and the presence and growth of multiple conceptuses in SOV cattle. SOV cattle were artificially inseminated with frozen-thawed semen at standing estrus (day 0), and the conceptuses were recovered by nonsurgical flushing of the uterus on day 13. In the SOV cattle, there were quadratic relationships between plasma P₄ concentration on days 4, 5 and 7 and conceptus length and between number of conceptuses in the uterus and conceptus length. These results suggest that conceptus growth in SOV cattle is regulated by both systemic P₄ level and number of conceptuses and that there are ranges of plasma P₄ concentrations and numbers of conceptuses in the uterus that are suitable for conceptus growth and development. Plasma P₄ concentrations on days 5 and 7, but not the numbers of conceptuses, were quadratically correlated with uterine glucose levels on day 13 in SOV cattle. In addition, conceptus length was positively correlated with uterine glucose level in SOV cattle. Accordingly, regardless of the number of conceptuses in the uterus, the plasma P₄ concentration was well correlated with the regulation of conceptus growth via changes in uterine glucose levels in SOV cattle.

Body temperature around induced estrus in dairy cows

The overall objective of this study was to study the influence of induced estrus on body temperature, comparing 5 distinct intervals around induced estrus and to determine the diurnal pattern from 4±1 d before to 4±1 d after induced estrus. Sixteen estrous cycles of 9 postpartum dairy cows were synchronized with 2 injections of PGF2α, 10 d apart. After the second PGF2α injection on d 10, temperature loggers were inserted into the vaginal cavity for a 12±1-d period. Two days later, a third dose of PGF2α was injected to induce estrus. After confirmation of a corpus luteum, loggers were removed on d 5±1. Observation of estrus, rectal palpation, and ultrasound scanning to determine ovulation were carried out every 4±1h, beginning at 12h after the third PGF2α injection. Blood samples from the vena coccygea mediana were collected twice daily from d 11 to 12 and every 4±1h after the third PGF2α injection until ovulation. Vaginal temperature was recorded every 5min and averaged to hourly means for the following 5 periods: 1) 48h preceding the third PGF2α injection, 2) from the third PGF2α injection to first signs of estrus, 3) estrus to ovulation, 4) a 4-h interval in which ovulation occurred, and 5) a 96-h post-ovulation period. High body temperatures (39.0±0.5°C) and low progesterone (P4) concentrations (<0.5ng/mL) were observed during estrus, whereas low body temperatures were observed from PGF2α injection to estrus (38.6±0.3°C) and around ovulation (38.5±0.2°C), respectively. An association between body temperature and serum P4 concentrations did not exist. However, P4 concentrations on d 11 and 12 were high (5.0±1.5ng/mL) and decreased (0.9±0.2ng/mL) after ovulation. Diurnal temperature rhythms were similar before and after estrus. Vaginal temperature before estrus (d 11 and 12) was slightly (0.1°C) higher compared with the post-ovulation period.

Distribution of Spermatozoa and Embryos in the Female Reproductive Tract after Unilateral Deep Intra Uterine Insemination in the Pig

Distribution of Spermatozoa and Embryos in the Female Reproductive Tract after Unilateral Deep Intra Uterine Insemination in the Pig

Gametes Alter the Oviductal Secretory Proteome

The mammalian oviduct provides an optimal environment for the maturation of gametes, fertilization, and early embryonic development. Secretory cells lining the lumen of the mammalian oviduct synthesize and secrete proteins that have been shown to interact with and influence the activities of gametes and embryos. We hypothesized that the presence of gametes in the oviduct alters the oviductal secretory proteomic profile. We used a combination of two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometry to identify oviductal protein secretions that were altered in response to the presence of gametes in the oviduct. The oviductal response to spermatozoa was different from its response to oocytes as verified by Western blotting. The presence of spermatozoa or oocytes in the oviduct altered the secretion of specific proteins. Most of these proteins are known to have an influence on gamete maturation, viability, and function, and there is evidence to suggest these proteins may prepare the oviductal environment for arrival of the zygote. Our findings suggest the presence of a gamete recognition system within the oviduct capable of distinguishing between spermatozoa and oocytes.

Regulation of ipsilateral and contralateral bovine oviduct epithelial cell function in the postovulation period: a transcriptomics approach.

We studied differential gene expression in ipsilateral and contralateral bovine oviduct epithelial cells using a combination of subtracted cDNA libraries and cDNA array hybridization. Four Simmental heifers were synchronized and slaughtered 3.5 days after they entered standing heat. Epithelial cells were isolated from ipsilateral and contralateral oviducts. To identify genes that are differentially regulated in ipsilateral and contralateral epithelium, subtracted cDNA libraries were produced by suppression subtractive hybridization and analyzed by cDNA array hybridization. Sequencing of cDNAs showing differential expression levels in ipsilateral and contralateral epithelium revealed 35 different cDNAs, 30 of which matched genes with known functions and 5 of which matched genes without a known function. The majority of genes (n = 27) were expressed at a higher level in the ipsilateral oviduct, but for some genes (n = 8), mRNA abundance was higher in the contralateral oviduct. The regulated genes or their products include a variety of functional classes such as cell-surface proteins, cell-cell interaction proteins, members of signal transduction pathways, immune-related proteins, and enzymes. Identification of genes differentially regulated in ipsilateral and contralateral oviduct epithelial cells is the first step toward a systematic analysis of local mechanisms that regulate the function of the bovine oviduct epithelium in the postovulation period.

Further observations on abnormal brain development caused by prenatal A-bomb exposure to ionizing radiation.

The pervasiveness of abnormal brain development caused by prenatal exposure to ionizing radiation is still largely unknown. The relationship between A-bomb radiation dose and two measures of neuromuscular performance, one of grip strength and the other of the fine motor coordination required in repetitive action, is described. A multivariate analysis of covariance was used to evaluate the effect of several covariates, such as prenatal radiation exposure and some physical measurements or IQ adding city and sex as categorical factors. When mentally retarded cases were included, a statistically significant effect of radiation exposure on the grip strength and repetitive-action test scores was seen in the 8-15-week postovulation period, and a statistically suggestive effect at 16-25 weeks postovulation. No effect of radiation exposure on the two test scores was noted for prenatal exposure in either of the aforementioned periods when mentally retarded cases were excluded, but a statistically significant diminution of IQ was noted for exposures > or = 16 weeks postovulation. We discuss, from the biological perspective, the projected standard scores for exposures > or = 16 weeks postovulation, and the possibility of lower IQ, small head and mild mental retardation related to radiation exposures < or = 15 weeks postovulation with mentally retarded cases excluded.

The metabolic clearance rate of estradiol-17β in rainbow trout, Salmo gairdneri R., estimated by both single injection and constant infusion methods: Increase during oocyte maturation

A dual cannulation of free-swimming rainbow trout is used to estimate the metabolic clearance rate (MCR) of Estradiol-17β (E 2-17β) by both single injection and constant infusion methods. It is shown that E 2-17β MCR changes significantly during the progress of oogenesis, mainly at the end of the sexual cycle. The same changes in MCR and very similar values are found with both single injection and constant infusion methods: MCR is stable (28.8 ml/hr/kg) from the postovulation period (throughout endogenous vitellogenesis) to early exogenous vitellogenesis. It decreases significantly during advanced exogenous vitellogenesis (18.7 ml/hr/kg) and increases clearly at the onset of oocyte maturation (40.9 ml/hr/ kg). A direct relationship between MCR and plasma E 2-17β occurs: Plasma E 2-17β levels increase (advanced exogenous vitellogenesis) when MCR decreases. Then estradiol decline takes place at the same time that MCR reaches its highest values (oocyte maturation). An increase in MCR is probably one event required to allow the establishment of an appropriate hormonal environment for oocyte maturation.

Plasma cortisol levels of female rainbow trout ( Salmo gairdneri) at the end of the reproductive cycle: Relationship with oocyte stages

The concentrations of plasma cortisol were determined in two populations of female rainbow trout at the end of their reproductive cycles. In females ending vitellogenesis or having oocytes with germinal vesicles in peripheral positions, mean cortisol levels were low (about 8 to 10 ng/ml). Cortisol concentrations remained low during oocyte maturation (about 8 and 11 ng/ml). In contrast, a 3-fold cortisol increase was observed in females sampled in the postovulation period (about 26 and 31 ng/ml). These results are discussed in relation to other studies on endocrinological changes during the spawning season with emphasis on the possible role of cortisol in reproduction in female teleosts.

Effect of ovulation on haem metabolism in rabbits.

To investigate the origin of the cyclic changes in the rate of endogenous carbon-monoxide production (nCO) during the menstrual cycle, haem turnover was determined before and after chorion gonadotropic hormone-induced ovulation in six female rabbits. 14C-labelled delta-aminolevulinic acid and glycine were administered and the excretion rate of 14CO (A14CO) was measured for determination of hepatic and bone-marrow haem turnover, respectively. Carbon-monoxide production (nCO) was measured to estimate total haem turnover. After ovulation A14CO was increased significantly the first 2 h of the early labelled peak after 14C-ALA administration and was increased also at the first determination during the early peak after 14C-glycine but statistically not significantly. The total excretion of labelled CO during the period of the early labelled peak was not increased with any of these precursors for haem synthesis. On the other hand nCO was increased 34% (P less than 0.05) during the post-ovulation period. As the increase in 'unassigned' haem turnover was small and may be unaccompanied by a contemporary increase in bilirubin/CO production, it was concluded that the increase in nCO during the post-ovulation period essentially depends on increased destruction of circulating red cells in the rabbit.

Temporal aspects of macroscopic changes in rainbow trout ( Salmo gairdneri) oocytes before ovulation and of ova fertility during the post-ovulation period; effect of treatment with 17 α-hydroxy-20 β-dihydroprogesterone

Ovulation induced by a single injection of 17 α-hydroxy-20 β-dihydroprogesterone (17 α–20 β P) in rainbow trout at the subperipheral germinal vesicle stage was compared with spontaneous ovulation. Three criteria were considered: the time course of the maturation-ovulation sequence, the embryo and fry viability, and the rate of aging of ova retained in the body cavity after ovulation. Following treatment with 17 α–20 β P at 13°C, the various stages of oocyte maturation took place between day 1 and day 4 and ovulation occurred on days 3, 4, and 5 with a peak on day 4. The same timing was observed in the case of spontaneous ovulation. Treatment with 17 α–20 β P did not affect embryo or fry viability until the end of yolk sac resorption. Lastly, in both natural and steroid-induced ovulation, ova fertility had decreased significantly by the 9th day of retention in the female body cavity, at 13°C. The overall rate of ova aging was similar in both groups. These data demonstrate that ovulation induced by 17 α–20 β P at the subperipheral germinal vesicle stage is close to the natural, spontaneous, process.

Topographical distribution of sialic acids and related enzymes in toad oviduct

1. 1. Sialic acids of the toad oviduct mucoprotein are distributed following a distinct pattern. This pattern was found to be identical for neuraminidases and N-acetylneuraminate lyases—two enzymes which are involved in the metabolic pathway of these compounds. 2. 2. High levels of sialic acids were found in the preovulatory period, but a decrease of about 80 per cent was observed in the postovulation period. 3. 3. N-acetylneuraminate lyase activities are partially lost after ovulation. However, only a few changes in the total activity of neuraminidases were found.

Sorby Fellowship: Dr. W. S. Bullough

THE Royal Society has appointed Dr. W. S. Bullough, lecturer in zoology at McGill University, Montreal, to be Sorby research fellow in the University of Sheffield in succession to Dr. K. Mellanby. Dr. Bullough is a graduate of the University of Leeds. While holding first a research fellowship and later a lectureship in the Department of Zoology there, Dr. Bullough carried out investigations on the internal and external environmental control of reproductive cycles in fishes, birds and mammals. His researches on the endocrine glands in relation to bird behaviour throw much light on the reality of the distinction between British and Continental races of starlings, and evidence has been adduced for regarding Continental immigrant starlings as carriers of foot and mouth disease, responsible for outbreaks in British cattle. An important conclusion,arising from his work on mammals is the power of the oestrogens to stimulate cells in the ovary to mitotic activity, thus leading at the post-ovulation period to a replenishment of the ovary with a new stock of oogonia. This mitogenic function of the sex hormones would seem to be the field of research now to be explored by Dr. Bullough in his tenure of the Sorby fellowship in the Department of Zoology at Sheffield. He hopes to take up his new work during the summer.