Different Stages Of Oestrous Cycle Research Articles

Behavioral and Physiological Differences in Female Rabbits at Different Stages of the Estrous Cycle.

Estrus involves a series of complex physiological signs and changes in behavior before ovulation, which play a crucial role in animal reproduction. However, there have been few studies that evaluate behaviors during the different stages of estrus cycle in female rabbits. Therefore, more detailed information is needed on distinguishing the various stages of the estrous cycle. This study explored the behavioral and physiological differences at various estrous cycle stages in female New Zealand White rabbits. The continuous recording method was employed to record the daily behaviors of twenty postpartum female rabbits during the estrous cycle. Compared with the diestrus stage, the duration of foraging and drinking behavior in estrus decreased significantly, and the frequency of grooming and biting behaviors increased (p < 0.05). Differences in reproductive hormone levels (FSH, LH, P4, and E2) and follicle development were measured at each stage via ELISA and HE staining. The FSH and LH levels showed an increasing trend and then decreased, with the lowest being in late estrus (p < 0.05). The P4 level was the lowest in estrus (p < 0.05), and E2 showed a gradually increasing trend. There was no significant difference in the number of primordial follicles at each stage, but the number of primary follicles in estrus was significantly higher than at the other stages (p < 0.05). To further understand the molecular regulation mechanism of the estrous cycle in female rabbits, we analyzed the ovarian transcription patterns of female rabbits in diestrus (D group) and estrus (E group) employing RNA-seq. A total of 967 differentially expressed genes (DEGs) were screened from the ovaries of female rabbits between the diestrus and estrus groups. A KEGG analysis of DEGs enriched in the estrogen signaling pathway, aldosterone synthesis, and secretion pathway, such as CYP19A1 and IGF1R, was performed. The rabbits' behavior, related physiological hormones, and molecular regulation also differed at different estrous cycle stages. The results provide recommendations for the adequate management practices of postpartum re-estrus and breeding female rabbits.

VSELs and OSCs together sustain oogenesis in adult ovaries and their dysfunction results in age-related senescence, PCOS, POI and cancer

Multiple studies using single-cell RNA sequencing (scRNAseq) have failed to detect stem cells in adult ovaries. We have maintained that two populations of ovarian stem cells including pluripotent, very small embryonic-like stem cells (VSELs) and tissue-committed ‘progenitors’ termed ovarian stem cells (OSCs) can easily be detected in Hematoxylin and Eosin-stained ovary surface epithelial (OSE) cells smears prepared from both mice and human ovaries. Most likely the stem cells never get subjected to scRNAseq since they pellet down only by centrifuging cells suspension at 1000 g while cells for scRNAseq were invariably prepared by centrifuging at 200-400 g. A recent article provided further explanation for the failure of scRNAseq to detect ovarian stem cells. Extensive reanalysis of data (generated by scRNAseq) using an advanced software successfully detected OSCs and meiotic markers supporting neo-oogenesis in adult human ovaries. But this article remained critical on the biological relevance of VSELs and their relationship with OSCs. By carefully studying the OSE cells smears (which hold VSELs, OSCs and germ cell nests GCNs), prepared by partial trypsin digestion of intact mice ovaries during different stages of estrus cycle, we have successfully delineated novel functions of VSELs/OSCs in vivo under physiological conditions. VSELs undergo asymmetrical divisions to self-renew and give rise to slightly bigger OSCs which in turn undergo symmetrical divisions and clonal expansion to form GCNs, regular neo-oogenesis and follicle assembly. GCNs have been earlier described in fetal ovaries and during OSE cells culture (from adult ovaries) in response to FSH treatment. Dysfunction of VSELs/OSCs (which express ERα, ERβ, FSHR) due to neonatal exposure to endocrine disruption results in ovarian insufficiency and polycystic ovaries. VSELs have also been implicated in ovarian cancer. Age-related ovarian senescence/menopause is also due to dysfunction and blocked differentiation of VSELs/OSCs. These novel findings in vivo along with abundant in vitro and lineage tracing studies data in published literature provides huge scope for further research, offers novel avenues to manage ovarian pathologies and calls for re-writing of textbooks.

Doppler ultrasonography of ventral perineal artery in bitches during different stages of oestrous cycle

This study aimed to evaluate the Doppler ultrasonographic features of ventral perineal artery of bitches during different phases of oestrous cycle. Sixteen pluriparous bitches were subjected to transperineal Doppler ultrasonography during different stages of oestrous cycle by confirming the stage by exfoliative vaginal cytotlogy (EVC) and vaginoscopy. The resistivity index (RI), pulsatility index (PI), peak systolic velocity (PSV), end diastolic velocity (EDV) and systolic/ diastolic velocity (S/D) were analysed. No significant difference was found between the Doppler velocimetric parameters of ventral perineal artery during different phases of oestrous cycle by trasnperineal Doppler ultrasonography.

Expression profiling of candidate embryotrophic genes of buffalo oviduct during different stages of oestrous cycle

The aim of the present study was to identify the gene expression profile of three candidate genes namely heat shock protein 70, oviductal glycoprotein and osteopontin in buffalo oviduct during different stages of the oestrous cycle. Slaughter house derived buffalo oviducts were categorized as belonging to early, mid and late phase of the oestrous cycle based on the morphological appearance of CL and progesterone concentration. The relative abundance of each of the candidate gene transcript was quantified by real time RT-PCR. Transcripts of all the three candidate genes were found to be expressed in OEC throughout the oestrous cycle. The results of the present study demonstrate that gene expression in the buffalo oviduct is clearly regulated during the oestrous cycle, as these candidate genes play a crucial role in several reproductive processes. It was found that Hsp 70 gene was significantly upregulated in OEC belonging to the early and late phases when compared to mid phases of the cycle. The expression of OVGP mRNA was found to be maximum during the early phase and it remained low during the mid and late phases while expression of OPN mRNA was maximum during the early phase and declined sequentially during the mid and late phase of oestrus cycle.

PGP 9.5- Immunoreactivity in The Ovary at Different Stages of Oestrous Cycle in Rats

The reproductive process in female mammals is characterized by cyclic alteration in the female tract. During the oestrous cycle, the primordial follicle will be developed into the Graafian follicle before the ovulation and it takes place under the influence of hormonal control. This work was carried out to study the general pattern of innervation in the ovary at different stages of the oestrous cycle. Twenty-four adult female Sprague Dawley rats were used to perform the goal of the study. These rats were sacrificed after the detection of their cycle stage by vaginal smears and the ovaries were fixed and section using a frozen cryostat. Detection of nerve fibers was done using the immunohistochemistry technique. The results from this study showed that there is innervation in the ovary throughout the oestrous cycle indicated by the presence of PGP 9.5-immunoreactive nerve fibres. The number of nerve fibres found during each stage of the oestrous cycle significantly varies; the nerve fibre count during the oestrus stage was significantly higher (P < 0.05) than the nerve fibre count at proestrus, metestrus, and diestrous stage. In conclusion, immunohistochemistry PGP 9.5 marker was a useful approach and indicator for nerve fibers distribution in organs which can be changed with different physiological conditions.

Effect of season on hormonal profile and some biochemical parameters at different stages of estrous cycles in Baladi goats

Understanding the seasonal patterns of estrus cycle in caprine is crucial to develop the efficient breeding plans in the subtropics. Thus, the aim of the current research was to evaluate the effects of breeding season on hormonal profile and blood biochemical indices at different stages of estrus cycle in normal breeding or out-of-season breeding in goats. Forty-four Baladi goats were monitored for a period of eight months (July–February). Baladi goats exhibit a normal seasonal breeding (NS) at midsummer and continue through the autumn season (68%), with a considerable percentage of females having estrus signs during out-of-season (OS) period (32%). At the mid and late luteal phases of estrus cycles, the NS breeding group had significantly higher serum progesterone level than that reported in the OS group (p = 0.013 and 0.039, respectively). At the estrus and late luteal phases of estrus cycles, the NS breeding group had significantly higher serum β-estradiol level than that reported in the OS group (p = 0.022 and 0.001, respectively). Compared to the OS group, the NS breeding group had significantly higher serum cholesterol at the mid and late luteal phases of estrus cycle (p = 0.001 and 0.016, respectively), and higher serum glucose level in the early luteal phase of the cycle (p = 0.009). In conclusion, the NS breeding goats had superior progesterone (mid-luteal and late luteal phases) and estradiol (estrus and late luteal phases) profiles than that reported in the OS group. This may indicate specific approaches to maintain the breeding efficiency of goats during the out-of-season period.

Ultrastructural and immunophenotype distribution of Telocytes in female genital tract of adult albino rats

Background: Few information was given about Telocyte (TC) which was recently discovered in the lastfew years.Aim of the work: This study was designed to give full histological, immunohistochemichal andultrastructural preview on TCs distribution in the female genital tract.Material and method: After vaginal smear examination, thirty rats in diestrus phase were subjected forthis study. Uterine, fallopian tube and vaginal specimens were taken and processed for both light andelectron microscopic examination.Results: TCs showed weak positive ER-α and marked immunoexpression of PR-A and CD34 in theendometrial stroma and around the glands, in stratum vascular and outer longitudinal smooth muscle layersof the uterus, serosa of the fallopian tube and in the lamina propria in addition to the connective tissueunder vaginal epithelium and around and within the bundles of the vagina. Ultrastructurally, the uterus,fallopian tube and vagina showed triangular or stellate- shaped TCs that contained elongated nucleusoccupying the whole cell body with thin band of marginal heterochromatin and prominent nucleolus andhad one or more telopodes (TPs) with dichotomous pattern of branching. TPs had thin podomere andthick podom. Podom contains many mitochondria, rough endoplasmic reticulum (RER), many caveolaeand pinchedout vesicles. TCs had either homocellular junction between them or heterocellular junctionwith adjacent smooth muscle cells. TCs were surrounded by collagen fibers.Conclusion:TCs are new type of cells with special ultrastructure and immunophenotype characters thatare detected in the female genital tract ,therefore further studies on their distribution in the female genitaltract during different stages of estrus cycle, and trying to correlate between their distribution and theirrole in controlling infertility or myometrial contraction during pregnancy should be considered.

Expression and localization of angiopoietin family in corpus luteum during different stages of oestrous cycle and modulatory role of angiopoietins on steroidogenesis, angiogenesis and survivability of cultured buffalo luteal cells.

The objective of this study was to document the expression and localization of angiopoietin (ANGPT) family members comprising of angiopoietin (ANGPT1 and ANGPT2), and their receptors (Tie1 and Tie2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle, and the modulatory role of ANGPT1 and ANGPT2 alone or in combinations on progesterone (P4 ) secretion and mRNA expression of phosphotidylinositide-3kinase-protein kinase B (PI3K-AKT), phosphoinositide-dependent kinase (PDK), protein kinase B (AKT), Bcl2 associated death promoter (BAD), caspase 3 and von willebrand factor (vWF) in luteal cells obtained from midluteal phase (MLP) of oestrous cycle in buffalo. Real-time RT-PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors whereas, the P4 secretion was assessed by RIA. The mRNA and protein expression of ANGPT1 and Tie2 was maximum (p<.05) in mid luteal phase (MLP) of oestrous cycle. The ANGPT2 mRNA and protein expression was maximum (p<.05) in early luteal phase, decreased in MLP and again increased in late luteal phase of oestrous cycle. ANGPT family members were localized in luteal cells and endothelial cells with a stage specific immunoreactivity. P4 secretion was highest (p<.05) with 100ng/ml at 72hr when luteal cells were treated with either protein alone. The mRNA expression of PDK, AKT and vWF was highest (p<.05) and BAD along with caspase 3 were lowest (p<.05) at 100ng/ml at 72hr of incubation period, when cultured luteal cells were treated with either protein alone or in combination. To conclude, our study explores the steroidogenic potential of angiopoietins to promote P4 secretion, luteal cell survival and angiogenesis through an autocrine and paracrine actions in buffalo CL.

Quantity of IL-2, IL-4, IL-10, INF-γ, TNF-α and KC-like cytokines in serum of bitches with pyometra in different stages of oestrous cycle and pregnancy.

The occurrence of the pyometra is most common in the first half of the dioestrus when there is decreased cellular immunity associated with increased serum concentration of progesterone in females. The aim of this study was to determine the immunological profile of bitches with pyometra, studying serum levels of IL-2, IL-4, IL-10, IFN-γ, KC-like and TNF-α and comparing them with those of healthy bitches in anoestrus, dioestrus and pregnant. Forty females were divided into four experimental groups: group 1 (G1): with pyometra (n = 10); group 2 (G2): bitches in the second week of gestation (n = 10); group 3 (G3): in anoestrus (n = 10); and group 4 (G4): in dioestrus (n = 10). The serum levels for IL-2, KC-like, INF-γ and TNF-α were similar for all experimental groups. The values obtained for IL-10 were found increased (p < 0.001) in animals in dioestrus and pyometra compared with females in anoestrus and pregnant, and the levels of IL-4 observed were significantly greater (p < 0.001) in bitches with pyometra when compared with others. The cytokine profile in animals with pyometra is similar to bitches in dioestrus for IL-10 and had increase in IL-4 for bitches with pyometra, which represents an anti-inflammatory these cases. This suggests the presence of an immunosuppressive state in both cases, which may explain the propensity of bitches in dioestrus to be affected by pyometra and the severity of the disease on these animals.

OVARIAN RESPONSE OF DAIRY COWS TO PROGESTERONE COMBINED ON

The objective of this study was to evaluate the response of ovaries in estrus synchronizationprotocol using GnRH-PGF2α based protocol combined progestin in a herd with tie-stall housing system.A total of 20 Holstein Friesian cows at different stages of estrus cycle in a dairy herd were enrolled inthe present study. The cows were randomly allocated into two treatment groups; with and without CIDR(Controlled internal drug release) insertion. All cows received 100 μg of GnRH I.M. at the beginning ofthe treatment (d 0) without regard to the stages of the estrus cycle followed by 25 mg PGF2α IM 7dayslater. Cows in CIDR group were inserted CIDR into the vagina at the time of GnRH administration andwere removed on the day of PGF2α administration. estrus signs were checked twice daily starting onday-2 after initiation of the protocol, except cows in CIDR group the estrus signs were checked startingon day-8 of the protocol. The animals showing estrus signs were noted. Blood samples were collectedfrom all animals on the days of GnRH and PGF2α treatments and on day-10 after initiation of protocolfor progesterone concentration. The results of this study showed that 30% animals in cows withoutCIDR insertion showed estrus signs prior to PGF2α injection. Involving CIDR to synchronized estruswith GnRH-PGF2α based protocol avoided the occurrence of premature estrus and maintained highprogesterone concentration on the day of PGF2α administration. It is concluded that ovarian responseafter involving CIDR in the protocol for estrus synchronization especially using combination of GnRHand PGF2α were much effective to synchronize the initiation of estrus in dairy cows. Likewise, the useof progesterone avoided premature estrus.

Anandamide Levels Fluctuate in the Bovine Oviduct during the Oestrous Cycle

Mammalian oviduct acts as a reservoir for spermatozoa and provides an environment in which they may compete for the opportunity to fertilize the oocyte. Whilst in the oviduct spermatozoa undergo capacitation essential for fertilization. Sperm-oviduct interaction is essential for sperm capacitation and is a tightly regulated process influenced by the local microenvironment. Previously we reported that the endocannabinoid anandamide (AEA) regulates sperm release from epithelial oviductal cells by promoting sperm capacitation. The aims of this work were to measure the AEA content and to characterize the main AEA metabolic pathway in the bovine oviduct and determine how these change through the oestrous cycle. In this study, the levels of AEA and two other N-acylethanolamines, N-oleoylethanolamine and N-palmitoylethanolamine, were measured in bovine oviduct collected during different stages of oestrous cycle by ultra high performance liquid chromatography tandem mass spectrometry. Results indicated that intracellular oviductal epithelial levels of all three N-acylethanolamines fluctuate during oestrous cycle. Anandamide from oviductal fluid also varied during oestrous cycle, with the highest values detected during the periovulatory period. Endocannabinoid levels from ipsilateral oviduct to ovulation were higher than those detected in the contralateral one, suggesting that levels of oviductal AEA may be regulated by ovarian hormones. The expression and localization of N-acylethanolamines metabolizing enzymes in bovine oviduct were also determined by RT-PCR, Western blot, and immunohistochemistry but no change was found during the oestrous cycle. Furthermore, nanomolar levels of AEA were detected in follicular fluids, suggesting that during ovulation the mature follicle may contribute to oviductal AEA levels to create an endocannabinoid gradient conducive to the regulation of sperm function for successful fertilization.

Elastase, Myeloperoxidase, and Alkaline Phosphatase Release and Free Radical Generation in Neutrophils Isolated from Blood of Sows at Different Stages of Oestrous Cycle

Abstract The aim of the study was to assess the influence of the oestrous cycle phase on neutrophil secretory activity and to extrapolate it to susceptibility to uterine infections. The obtained results indicate that the highest enzyme release seen in the late follicular phase (elastase release was 42.18 ±3.11% of maximal release, myeloperoxidase was 45.0 ±5.12%, and alkaline phosphatase was 44.75 ±9.0%) was related to the level of 17β-oestradiol in plasma. Similarly, a free radical generation was also the most enhanced during this phase. Significantly lower values were obtained from sows during the luteal phase in regard to both enzyme release (36.62 ±3.58% for elastase, 27.87 ±8.7% for myeloperoxidase, and 22.12 ±2.4% for alkaline phosphatase), and that of free radicals (2.28 1.6 μM/106 cells for nitric oxide and 2.47 0.6 nM/106 cells for superoxide).

In vitro Survival of Follicles Collected from Domestic Cats' Ovaries at Different Stages of Oestrous Cycle and Cultured with IGF‐1

Optimal conditions for in vitro culture of feline ovarian follicles have not yet been defined. Follicular development is regulated by intraovarian growth factors, as insulin-like growth factor (IGF-1), and during the different stages of the oestrous cycle, follicles are exposed to specific hormonal environments. The aim of this study was to investigate the effect of IGF-1 on in vitro growth and granulosa cell (GC) viability of preantral follicles collected from domestic cats at follicular and luteal phases of the oestrous cycle. Oestrus and ovulation were induced in 12 cats. A total of 39 and 32 follicles collected at the follicular and luteal phases, respectively, were individually cultured in vitro for 6 days in minimum essential medium media supplemented with or without IGF-1 (100 ng/ml). Follicles collected during the follicular phase and cultured without IGF-1 displayed a significant increase in size and higher GC viability (46.5 ± 22.1 μm, 66.7%, respectively) than that of follicles collected at the luteal phase and cultured without IGF-1 (26.7 ± 14.4 μm, 50%, respectively; p < 0.05). In contrast, when IGF-1 was added to the culture medium, no differences were observed in size or GC viability between follicles collected at the two phases of the cycle. Nonetheless, follicles collected at the luteal phase and cultured with IGF-1 had a significant increase in their diameter and GC viability (31.9 ± 15.9 μm, 63.6%, respectively) than that cultured without IGF-1 (26.7 ± 14.4 μm, 50%, respectively; p < 0.05). These data suggest that in vitro growth and GC survival of feline preantral follicles are affected by the oestrous cycle phase, and the IGF-1 exerts a positive effect on follicles collected at the luteal phase.

Maternal deprivation-induced stress responses in female rats

To investigate the effect of maternal deprivation on the activity of hypothalamo-pituitary-adrenal (HPA) axis, acute stress response and the sex hormone receptors expression in hypothalamic paraventricular nucleus (PVN) in female rats. Maternal deprivation model was induced in female Sprague-Dawley (SD) rats. Foot shock was given at different stages of estrus cycle during the adulthood. Plasma estradiol, testosterone and adrenocorticotropin (ACTH) levels were determined by radioimmunoassay; and plasma corticosterone level was measured by enzyme linked immunosorbent assay. The expression of androgen receptor (AR) and estrogen receptor (ER-β) in the hypothalamic PVN was detected by immunohistochemistry. Decreased plasma ACTH and corticosterone levels were found in the proestrus of female rats with maternal deprivation (P=0.012 and P=0.019, respectively). A significant down-regulation (P=0.008) of PVN-AR, but not PVN-ER-β expression was found in female rats with maternal deprivation. Maternal deprivation may reduce the HPA axis activity in female SD rats, which is closely correlated with the fluctuation of the circulating sex hormones. The androgen in the hypothalamus seems to play a more important role than the estrogen in this procedure.

Gonadotropin treatment augments postnatal oogenesis and primordial follicle assembly in adult mouse ovaries?

BackgroundFollicle stimulating hormone (FSH) exerts action on both germline and somatic compartment in both ovary and testis although FSH receptors (FSHR) are localized only on the somatic cells namely granulosa cells of growing follicles and Sertoli cells in the seminiferous tubules. High levels of FSH in females are associated with poor ovarian reserve, ovarian hyper stimulation syndrome etc. and at the same time FSH acts as a survival factor during in vitro organotypic culture of ovarian cortical strips. Thus a further understanding of FSH action on the ovary is essential. We have earlier reported presence of pluripotent very small embryonic-like stem cells (VSELs express Oct-4A in addition to other pluripotent markers) and their immediate descendants ‘progenitors’ ovarian germ stem cells (OGSCs express Oct-4B in addition to other germ cell markers) in ovarian surface epithelium (OSE) in various mammalian species including mice, rabbit, monkey, sheep and human. Present study was undertaken to investigate the effect of pregnant mare serum gonadotropin (PMSG) on adult mice ovaries with a focus on VSELs, OGSCs, postnatal oogenesis and primordial follicle assembly.MethodsOvaries were collected from adult mice during different stages of estrus cycle and after 2 and 7 days of PMSG (5 IU) treatment to study histo-architecture and expression for FSHR, pluripotent stem cells , meiosis and germ cell specific markers.ResultsPMSG treatment resulted in increased FSHR and proliferation as indicated by increased FSHR and PCNA immunostaining in OSE and oocytes of primordial follicles (PF) besides the granulosa cells of large antral follicles. Small 1–2 regions of multilayered OSE invariably associated with a cohort of PF during estrus stage in control ovary were increased to 5–8 regions after PMSG treatment. This was associated with an increase in pluripotent transcripts (Oct-4A, Nanog), meiosis (Scp-3) and germ cells (Oct-4B, Mvh) specific markers. MVH showed positive immuno staining on germ cell nest-like clusters and at places primordial follicles appeared connected through oocytes.ConclusionsThe results of the present study show that gonadotropin (PMSG) treatment to adult mouse leads to increased pluripotent stem cell activity in the ovaries, associated with increased meiosis, appearance of several cohorts of PF and their assembly in close proximity of OSE. This was found associated with the presence of germ cell nests and cytoplasmic continuity of oocytes in PF. We have earlier reported that pluripotent ovarian stem cells in the adult mammalian ovary are the VSELs which give rise to slightly differentiated OGSCs. Thus we propose that gonadotropin through its action on pluripotent VSELs augments neo-oogenesis and PF assembly in adult mouse ovaries.

Progesterone Downregulates Oestrogen-Induced Expression of CFTR and SLC26A6 Proteins and mRNA in Rats’ Uteri

Under progesterone (P) dominance, fluid loss assists uterine closure which is associated with pH reduction. We hypothesize that P inhibits uterine fluid secretion and HCO3− transport. Aim. to investigate the expression of Cystic Fibrosis Transmembrane Regulator (CFTR) and Cl−/HCO3− exchanger (SLC26A6) under P effect. Method. Uteri from ovariectomized steroid replaced and intact rats at different stages of oestrous cycle were analyzed for changes in protein and mRNA expressions. Results. P inhibits CFTR and SLC26A6 proteins and mRNA expression while oestrogen (E) causes vice versa. E treatment followed by P causes a reduction in these transporters' mRNA and protein. Similar changes occur throughout the oestrous cycle; that is, CFTR mRNA expression was high at proestrus while SLC26A6 mRNA and protein expressions were increased at proestrus and estrus. At diestrus, however, the expression of these transporters' protein and mRNA was reduced. Conclusion. Inhibition of CFTR and SLC26A6 expressions may explain the reduced fluid volume and pH under P-mediated effect.

CONSEQUENCES OF STRESS DURING SUCKLING FOR REPRODUCTIVE FUNCTION OF ADULT FEMALE RATS

For the study of consequences of stress in a critical period of the physiological suckling the reproductive function of adult female rats exposed to mother separation stress from 3rd till 15thday has been examined. It was found that such conditions led to the change of hormonal profile in the different stages of estrus cycle (higher concentration of testosterone, lower progesterone content in diestrus and flattening of estradiol peak in proestrus), that resulted into the prolongation of estrus cycle in the main over the diestrus phase. The body mass decrease, ovaries mass increase and adrenal mass diminishing at pregnant females, increase of intrauterine losses and inhibition of male fetus embryonal development, specify about production of poor quality oocite and disturbances of pregnancy maintenance at stressed rats.

In vitro Fertilization in Iraqi Local Goats

412 primary ova were used in the study of in vitro fertilization, these ova were collected from ovaries samples of does at different stages of oestrous cycle collected from abattoirs.These follicles were classified according to their size into large follicles (&gt; 2-6 mm) and small follicles (1-2 mm). Ova aspirated from these follicles were evaluated depending on the presence or absence of cumulus oophorus cells and on the presence of the first polar body. The aspirated ova from large and small follicles were maturated in tissue culture medium 199 to study their ability of maturation.. The microdrops technique from tissue culture (Medium 199) and granulosa cell co-culture technique were used for the maturation of ova, also the in vitro fertilization was inducted in these ova with the sperm which were capacitated in Bracket Medium. The results showed that the highest rate for ova aspiration and the highest rate of ova surrounded by cumulas oophorus were from the large, follicles. The size of follicle has a significant influence on the degree of ova growth and maturation. The results showed the absence of significant differences in the efficacy of two techniques used in the ova maturation and their ability of fertilization.

Prolactin receptor gene expression in rat splenocytes and thymocytes during oestrous cycle, pregnancy and lactation

Much evidence suggests that prolactin (PRL) has an immunoregulatory function. Part of this evidence is that the receptors for PRL are present on lymphocytes. Probably the effects of PRL on cells of the immune system depend on the level and specific forms of PRL-R present on the target cells. Therefore, PRL-R expression at both protein and mRNA levels was examined during oestrous cycle, pregnancy and lactation using Western blotting and PCR analysis. Antibody to the long form of PRL-R detected 84 and 42 kDa protein bands in the spleen but only 84 kDa band in the thymus. The expression pattern of these two protein bands was different in the spleen, suggesting that these two isoforms of PRL-R long form are differentially regulated by the hormones of oestrous cycle. In addition, depending on the tissue, the level of mRNA for the short and long forms of PRL-R showed a significant change at different stages of oestrous cycle. Moreover, 42 and 84 kDa PRL-R bands were detected in both spleen and thymus throughout the pregnancy and lactation; however, the expression pattern of 84 kDa protein band was different between tissues. This finding suggests that each tissue exhibits differential response to hormones which affect PRL-R content.

Variations During Lactation in Total and Differential Leukocyte Counts, N-acetyl-ß-D-glucosaminidase, Antitrypsin and Serum Albumin in Foremilk and Residual Milk from Non-infected Quarters in the Bovine

Quarter samples of foremilk and residual milk were taken approximately every second week from 2 days post partum (pp) throughout lactation month 9, from 5 dairy cows in their second lactation period. Bacteriologically positive milk samples were excluded. The aim was to study the variation in total and differential leukocyte counts, N-acetyl-beta-D-glucosaminidase (NAGase), antitrypsin (ATR) and serum albumin (BSA) in milk during the lactation period and different stages of oestrous cycle. Also the between milkings variation was studied from lactation month 4 to 9. At 2 days pp, each fraction of milk contained significantly higher numbers of leukocytes and had a higher activity of NAGase and ATR than later in the lactation period. In foremilk the highest content of BSA was also recorded at 2 days pp. From lactation month 2 to 9, stage of lactation had, in general, a slight effect on the variation in the variables measured. The total leukocyte count in residual milk tended to increase as lactation proceeded. The proportion of monocyte-macrophages in foremilk was significantly decreased during the last 4 months. NAGase and BSA in both fractions and ATR in residual milk increased significantly towards the end of the lactation period. From lactation month 4 to 9 the highest recorded ranges of variation between milkings, within quarter and stage of lactation, in the total leukocyte count, proportions of neutrophils, lymphocytes, monocyte-macrophages, NAGase, ATR and BSA in foremilk were 215 x 10(3)/ml, 42%, 34%, 54%, 6.68 units, 0.36 units and 0.14 mg/ml respectively. The corresponding figures in residual milk were higher except for the variation in BSA which was slightly lower in residual milk than in foremilk. In residual milk there was a positive correlation between the proportion of neutrophils and the total leukocyte count, when calculated on data from all cows and the entire experimental period. During the oestrous periods, the proportion of neutrophils in residual milk was higher than during the dioestrous periods. Foremilk and residual milk differed in the total as well as the differential leukocyte counts in all the various stages of lactation, whereas the contents of NAGase, ATR and BSA were equal in both fractions. The exception was 2 days pp when the proportions of lymphocytes were equal in both fractions and BSA-significantly higher in foremilk than in residual milk.