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1.
Bodó S Laczkó L Horváth G Baranyai B Szabó MH Dohy J Gócza E 《Acta veterinaria Hungarica》2002,50(4):469-479
This article presents a new, simple and rapid embryo biopsy method. The blastomere for genetic analysis can be separated from a precompacted mouse embryo after a partial zona digestion with the use of a holding pipette. For the micromanipulation only two microcapillaries and micromanipulators are needed. The development of the biopsied embryos was studied during in vitro culture and in utero following embryo transfer. There was no significant difference between the treated and the control groups in the ratio of embryos that developed to the blastocyst stage, although the biopsied embryos were delayed in their development because they contained significantly fewer cells compared to the control ones at the same stage. Although there was no difference in the ratio of implantation, the development of the biopsied embryos in utero was also delayed 12-24 hours on the 9th day of pregnancy. No difference in development was visible from the 13th day of pregnancy. Statistically, no differences were found in the developmental ratio (number of developed fetuses/transferred embryos) of the control and treated embryos during gastrulation (9th day of pregnancy), at the beginning of organogenesis (13th day of pregnancy) and before birth (19th day of pregnancy). The embryo biopsy method presented here can be a new and useful tool for preimplantation genetic diagnosis. 相似文献
2.
Two experiments were conducted to examine the consequences of attempting to control dystocia in Hereford heifers by restricting nutrition during late pregnancy. Nutritional level was controlled by varying feedlot rations in experiment 1 and by varying pasture availability in experiment 2. In neither experiment was the incidence of dystocia or stillbirths significantly affected by level of nutrition during late pregnancy. Calf birthweight was reduced and dam pelvic growth was retarded when the feed intake of heifers was restricted prior to calving. Clear evidence of the dangers associated with allowing heifers to lose too much weight in late pregnancy was provided by these experiments. The loss of around 0.5 kg/day during the last trimester of pregnancy was associated with weak labour, increase dystocia rates, increased perinatal mortality, reduced calf growth rate, prolonged post partum anoestrus and a reduced pregnancy rate (not all statistically significant differences). These effects were not evident in heifers which were maintaining or gaining weight at a moderate rate during late pregnancy. On the basis of this work it is suggested that heifers should be fed to allow modest rates of bodyweight gain (0--0.5 kg/day) during late pregnancy. 相似文献
3.
To understand the role of IGF-I in murine pregnancy, we studied the reproductive performance of IGF-I overexpressed mice. Fetal loss occurred only in the transfected uterine horn during day 10-15 of pregnancy. The placenta appeared healthy until Day 10 of pregnancy. From day 12, the decidua basalis of the transfected horn increased in thickness. The vascular lumen was expanded, and most of embryos were dead. Uterine natural killer cells did not undergo apoptosis from day 10 to day 15 when they usually go through apoptosis. Thus, it is likely that IGF-I plays a role in the decidual formation through regulation of uNK cells. This is the first report to demonstrate that IGF-I overexpression can cause fetal loss during murine placentation. 相似文献
4.
Lise Dybkjær Anne N. W. Olsen Finn Møller Karin H. Jensen Mette Giersing 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(2):83-91
The effects of group size during pregnancy (12 or 24 sows) and introduction methods on behaviour in multi-suckling pens were studied. The introduction methods were: A) (control) all sows and piglets were moved simultaneously to the multi-suckling pen on day 11 after farrowing; B) sows and piglets were moved simultaneously on day 14 after farrowing; C) sows were moved simultaneously and, two hours later, all piglets were moved simultaneously on day 11 after farrowing; D) each sow and her litter were moved separately at three-hours intervals on day 11 after farrowing. The effects of group size during pregnancy interacted with the effects of introduction method. When housed in groups of 12 during pregnancy, treatments B-D resulted in more initiated, but fewer successful nursings compared to A. However, when sows had been housed in groups of 24 during pregnancy, increased age (B) resulted in a decreased number of initiated nursings compared to A, but an increased nursing synchrony. The results indicate that it is possible to affect behaviour in multi-suckling pens through the social environment during pregnancy and by the choice of introduction method. 相似文献
5.
Maternal plasma leptin is elevated during pregnancy in several species, but it is unclear to what extent this elevation reflects changes in adiposity or energy balance. Therefore, Karakul ewes (n = 8) were fed to minimize changes in maternal energy status over the pregnancy-lactation cycle. They were studied 20-40 d before breeding and during mid pregnancy (d 50-60 post coitus [PC]), late pregnancy (d 125-135 PC) and early lactation (d 15-22 post partum). Consistent with the maintenance of near energy equilibrium in nongravid maternal tissues, maternal body weight was increased only during late pregnancy when the weight of the conceptus became significant and plasma concentrations of insulin, NEFA and glucose did not vary with physiological state. In contrast, maternal plasma leptin concentration rose from 5.3 to 9.5 ng/mL between prebreeding and mid pregnancy and then declined progressively through late pregnancy and early lactation. Leptin gene expression increased 2.3 fold in maternal white adipose tissue (WAT) from prebreeding to mid pregnancy and declined to prebreeding levels during early lactation. To determine whether tissue response to insulin was involved in this effect, insulin tolerance tests were performed. The maternal plasma glucose response declined from prebreeding to early lactation, but was not correlated with either plasma leptin concentration or WAT leptin mRNA abundance. In conclusion, pregnancy causes an increase in the synthesis of leptin in sheep. This stimulation does not require increases in adiposity or energy balance and is unrelated to the ability of insulin to promote glucose utilization. 相似文献
6.
本研究为对母兔妊娠期和哺乳期两个生理阶段水平衡的测定。选用的16只经产妊娠期新西兰母兔,随机分成四组,每组4只。试兔采食同一营养密度日粮。对照组为充分饲养组,日采食量为260克;其余三组的采食量各为对照组的90、80和70％(即各为230克、210克和190克)。结果表明:处于同一生理阶段试兔的水平衡不受饲料采食量多少的影响。母兔妊娠期每公斤体重每天的水平衡为18.9克;泌乳期为42.0克,差异极显著(P<0.01)。可见兔的生理状态是影响兔水平衡的重要因素。测得母兔妊娠期饮水占总摄水量的68.9％,泌乳期饮水占总摄水量的84.7％。母兔妊娠期每公斤体重饮水需112.7克,泌乳期需167.0克,饮水与饲料水之比各为1.49∶1和2.11∶1。由此表明:加强繁殖母兔的饲养管理不应忽视对其供给充足、洁净的饮水。 相似文献
7.
Rieko OKAME Keiko NAKAHARA Noboru MURAKAMI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):815-821
We measured the plasma levels of amino acids at various reproductive stages in female
rats, including the estrous cycle, pregnancy and lactation, and compared the resulting
amino acid profiles using two- or three-dimensional figures. These figures revealed that
the amino acid profiles of pregnant and lactating dams differed considerably from those
during the estrous cycle or in male rats. The plasma levels of individual amino acids were
almost the same between proestrus, estrus, metestrus and diestrus, and their profiles did
not differ significantly. However, the amino acid profiles changed during pregnancy and
lactation in dams. The plasma Ser level decreased significantly in mid and late pregnancy,
whereas Tyr, Gly and His decreased significantly in the late and end stages of pregnancy,
and Trp and Lys significantly decreased and increased at the end of pregnancy,
respectively. Much larger changes in amino acid profiles were observed during lactation,
when the levels of many amino acids increased significantly, and none showed a significant
decrease. Plasma Pro, Ser and Gly levels increased continuously from day 1 until day 15 of
lactation, whereas Asn and Met increased significantly from days 1 and 5 respectively
until the end of lactation. These results suggest that the profiles of plasma amino acids
show characteristic changes according to reproductive stage and that it may be necessary
to consider such differences when performing amino acid-based diagnosis. 相似文献
8.
Abortion and preterm birth of foals are major reasons for reproductive losses in the horse. Risk pregnancies require close supervision so that adequate treatment can be initiated in time. The aim of this study was to determine normal values in heart rate (HR) and heart rate variability (HRV) of the pregnant mare compared to her foetus and to detect physiological changes during ongoing gestation. In mares, the RR interval decreased from 1480±29 ms on day 270 of pregnancy to 1190±58 ms on day 330 of pregnancy (p<0.05). In contrast, foetal RR interval increased during the same time period from 611±23 ms on day 270 of gestation to 756±25 ms on day 330 of gestation (p<0.05). Concomitantly, maternal HR increased and foetal HR decreased. No further changes in RR interval occurred during the last 10 days before foaling, neither in the mare nor the foetus. In the last hours preceding parturition, maternal RR interval was lower than at all times earlier in pregnancy (average of 1037±13 ms) but did not change during this time. Maternal HRV did not change during gestation. Marked changes in HRV occurred only during the last minutes of foaling. Then, all HRV variables increased significantly (standard deviation of beat-to-beat interval: p=0.01, root mean square of successive beat-to-beat differences: p<0.01). The cardiovascular system of pregnant mares adapted to the demands of ongoing pregnancy with an increase in HR. We have no evidence that in healthy mares, pregnancy is a major stressor. 相似文献
9.
J C Hadley 《The Veterinary record》1975,96(25):545-547
The changes in total unconjugated oestrogen and progesterone concentrations in the peripheral blood of one bitch throughout a false pregnancy were measured. The levels of these hormones detected in 11 bitches when examined during a false pregnancy, and in 13 other bitches with pyometa are also reported. Oestrogen and progesterone concentrations were within normal limits in both of these conditions where single samples were obtained, but the bitch with false pregnancy studied in detail showed a raised oestrogen level during metoestrus. The significance of these results is discussed in relation to previous studies on the aetiology of false pregnancy and pyometra. 相似文献
10.
A detailed clinical-endocrine investigation was performed in 6 repeat breeder heifers (RBH) with the aim being to ascertain whether endocrine asynchronism exists at luteal regression and during early pregnancy. The heifers were first studied during an open cycle and then after insemination when 3 heifers became pregnant. Circulating plasma levels of PGF2 alpha metabolite were measured every 2nd h, while progesterone (P4) levels were measured every 6th h. The oestrous period and intervals between the onset of oestrus and ovulation were relatively longer, compared with what is normally seen in heifers. Plasma levels of P4 at the onset of oestrus were higher than normal, but it was concluded that the plasma levels of PGF2 alpha metabolite and P4 in RBH at luteal regression and early pregnancy were normal. 相似文献
11.
Most dairy ruminants are still lactating during early pregnancy, which could induce hormonal adaptations different from those observed during pregnancy alone. The incidence of concomitant lactation and pregnancy on plasma leptin has not been studied, and physiological factors involved in its regulation have not been addressed in goats. We assayed leptinemia throughout the pregnancy-lactation cycle in nulliparous and primiparous goats, starting 165 days prior to parturition and finishing 59 days after. During the first half of pregnancy, primiparous goats were lactating. Lactating non-pregnant primiparous goats were studied in parallel. Plasma leptin increased (+49%) up to mid-pregnancy in nulliparous, but not in primiparous goats. Furthermore, leptinemia was similar between pregnant and non-pregnant lactating primiparous goats, suggesting a strong leptinemia down-regulation by late lactation. Plasma leptin decreased from mid-pregnancy to parturition, more markedly in nulliparous goats, and remained depressed during early lactation at a similar level in both female types. It was lower, at 130 days of pregnancy, in goats carrying two fetuses. The leptinemia down-regulation by late pregnancy was highlighted by the lack of plasma leptin increase after drying-off late-pregnant primiparous goats, while it strongly increased in non-pregnant goats. The observation of leptinemia increase only in nulliparous goats suggests that it is not an essential endocrine adaptation during early pregnancy. By contrast, in both female types, the low leptinemia during transition from late pregnancy to lactation, and during late lactation, may be important for the adaptations that occur during lactation such as the partitioning of energy and nutrients towards essential functions and/or hyperphagia. 相似文献
12.
Barbosa dos Santos MH Rabelo MC Rocha de Aguiar Filho CR Dezzoti CH Reichenbach HD Neves JP Fernandes de Lima P Lemos de Oliveira MA 《Research in veterinary science》2007,83(2):251-255
The objective of this study was to determine the accuracy of early fetal sex determination by ultrasonic assessment of the relative location of the genital tubercle (GT) in goats at different stages of pregnancy as well as by the identification of fetal external genitalia. Pregnant animals were divided into three experimental groups (EI: n=21, EII: n=28, EIII: n=33). In EI, fetuses (n=27) were transrectally monitored daily from days 40 to 60 of pregnancy with a linear transducer (6.0 and 8.0MHz). In EII, fetuses (n=40) were examined once between days 45 and 70 of pregnancy by transrectal ultrasonography. In EIII fetuses (n=52) between days 100 and 120 of pregnancy, were submitted to a single transabdominal ultrasonography using a convex transducer (5.0 and 7.5MHz). Regardless of fetal sex diagnosis, 15/15 (EI), 13/16 (EII) and 9/14 (EIII) of single pregnancies and 10/12 (EI), 20/24 (EII) and 21/38 (EIII) of twin pregnancies were correctly identified. The accuracy of sex identification among EI (92.6%), EII (82.5%) and EIII (57.7%) was not statistically different (P>0.05). Identification of the GT in male fetuses was possible from day 45 onward. Changes in the GT position were not observed between days 53 and 60 of pregnancy. Accuracy of fetal sexing under field conditions is high in goats when ultrasound imaging is properly timed during pregnancy and when it is performed with proper equipment by experienced operators. 相似文献
13.
Polyclonal antisera for vascular endothelial growth factor (VEGF) and its two main receptor molecules, VEGF-I (Flt) and VEGF-II (KDR), were used in a conventional immunocytochemical staining method to localize these angiogenic ligand molecules in the endometrium and placenta of the mare during the oestrous cycle and pregnancy. The anti-VEGF and anti-Flt sera both labelled the lumenal and glandular epithelia of the endometrium throughout the oestrous cycle and both the invasive trophoblast cells of the endometrial cups and the non-invasive trophoblast of the allantochorion in pregnancy. The anti-KDR serum likewise stained the maternal and foetal epithelial layers during the oestrous cycle and pregnancy and it also labelled fibroblast-like cells in the endometrial and allantoic stromas and the endothelium of foetal and maternal capillaries. The results demonstrated that constant supplies of the principal vasculogenic and angiogenic factor, VEGF, and its two major receptors, Flt and KDR, are available on both the maternal and foetal sides of the placental barrier throughout gestation in the mare. They are presumed to facilitate the continuing development of the extensive foetal and maternal capillary networks that are such prominent features within the microplacentomes of the diffuse, epitheliochorial equine placenta. 相似文献
14.
Forty yearling Brucella-free ewes were inoculated with Brucella ovis by the conjunctival route in mid or late first pregnancy. Only a few ewes excreted B ovis during pregnancy and gave birth to stillborn lambs, but most of them excreted the organism at lambing or during lactation. One of the 11 lambs which were born alive but died before they were weaned was found to be infected postmortem. In contrast, none of the 46 surviving lambs which were reared in isolation until adulthood, was found to be infected. At weaning, the 40 ewes were mated again with five Brucella-free rams. Although many of the ewes excreted B ovis, none of the rams was found to be infected when necropsied after mating. Most of the ewes that became pregnant, all having excreted B ovis during their first pregnancy, cleared the infection during the second pregnancy. However, three remained persistently infected and excreted B ovis in their milk throughout the second lactation. None of the lambs born to these three ewes was found to be infected when necropsied at weaning. 相似文献
15.
The effects of pregnancy on the course of a infection and associated histopathological changes in thymus and small intestine were studied in outbred Swiss mice. For this purpose pregnant mice were orally infected with on various days (1 to 8) . Virgin, age-matched infected and non-infected mice served as controls.Pregnancy induced a severe but reversible thymus atrophy, which was even more marked during a infection. Thymus atrophy was most dramatic during mid and late pregnancy. During the involution phase a distinct increase in mast cells was observed.In animals infected during early pregnancy a not statistically significant inhibitory effect on worm expulsion was observed, whereas no effect was seen on the yield of muscle larvae, small intestine pathology (numbers of eosinophils, intestinal mast cells and globule leucocytes), blood eosinophilia and antibody production.Infection given during mid-pregnancy exerted an inhibitory effect on blood eosinophilia.On the basis of these results, it is concluded that although a severe atrophy of the thymus occurs during mid and late pregnancy, no effect on worm expulsion and intestinal pathology was observed when the infectious agent was given before thymus depletion started. 相似文献
16.
Oshima K Yoshihara K Kojima T Komatsu M Yamamoto N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(8):799-805
Macrophage colony-stimulating factor (M-CSF) is a hemopoietic cytokine with a primary role in placental physiology. Gene expression of M-CSF in the bovine endometrium shows a temporal upward trend during early and mid pregnancy. This study determined the plasma M-CSF levels during pregnancy using ELISA. In experiment 1, to investigate the relationship between the concentration of M-CSF in peripheral blood and pregnancy, the plasma M-CSF levels were determined in 125 pregnant and 21 non-pregnant Japanese Black cows. The pregnant animals were divided into nine groups based on the month of pregnancy. An ELISA for bovine M-CSF established previously was used according to the authors' instructions. In experiment 2, the plasma M-CSF level was determined to investigate the temporal changes in its concentration in the peripheral blood during pregnancy. In experiment 1, the plasma M-CSF level varied from month to month during pregnancy; the mean level in the first-month of pregnancy was significantly higher than those in the third and last months of pregnancy and non-pregnancy (P<0.05). In experiment 2, the plasma M-CSF level varied with the day of pregnancy (P<0.05). The mean level of plasma M-CSF decreased gradually until 6 weeks of pregnancy; it appeared to increase during weeks 7-9, then varied with several small peaks until 27 weeks of pregnancy and finally decreased gradually until parturition. These results suggest that the plasma M-CSF level may be related to changes in the uterus and placenta as pregnancy progresses. 相似文献
17.
18.
I Salvador MP Viudes-de-Castro J Bernacer EA Gómez MA Silvestre 《Reproduction in domestic animals》2005,40(6):526-529
An artificial insemination programme was carried out to study the effect of factors such as depth of semen deposition, inseminator skill, farm, sire and expression of oestrus on pregnancy rate in Murciano-Granadina (MG) goats during non-breeding season and using frozen semen. Frozen-thawed semen from six males was applied by three technicians to inseminate a total of 551 goats in 17 farms distributed throughout the Mediterranean area of Spain. Pregnancy rate was determined at 6 weeks after insemination by transabdominal ecography. Overall pregnancy rate was 57%. Farm and depth of semen deposition affected pregnancy rate, whereas the sire and the technician had no effect. The deeper the semen was deposited in the genital tract, the higher was the rate of pregnancy obtained, being greater when the catheter reached the uterus. In spite of the relevant difference observed (48.2% vs 59.0%), pregnancy rate of females not coming into oestrus until 30 h after sponge removal was not significantly different, compared with those showing oestrus during the OD procedure. In conclusion, our field assay data on AI in MG goat with frozen-thawed semen showed that post-cervical insemination presented significantly greater pregnancy rate in comparison to when semen is deposited in the vagina or in the caudal part of the cervix. 相似文献
19.
Histomorphological changes in the oviduct epithelium of the rabbit during early pregnancy 总被引：1，自引：0，他引：1
In this study, we determined the histomorphological changes in different regions of the oviduct (fimbriae, infundibulum, ampullae and isthmus) during early pregnancy (days 1-4) of the rabbit. It was observed that the number of secretory cells (PAS-positive cells) diminished in the fimbriae during the first 4 days of pregnancy with the corresponding increase in the number of non-secretory cells (PAS-negative cells). In contrast, there was an increase in the number of PAS-positive cells in the isthmus during early pregnancy. In both the infundibulum and the ampullae the number of PAS-positive cells was increased on day 3. A significant decrease in the height of the epithelium was observed in the fimbriae during early pregnancy. On the contrary, a significant increase in this parameter was observed in the isthmus during the first 3 days of pregnancy. A slight decrease in the height of the epithelium was observed in the infundibulum on day 4 of pregnancy, while in the ampullae it was significantly increased on days 1 and 3. The overall results indicate that during early pregnancy there is a selective modification in the histomorphological characteristics of the different regions of the rabbit oviduct. 相似文献
20.
Uterine natural killer (uNK) cells in the pregnant uterus are known to be associated with the normal development of the placenta. In the mouse pregnant uterus, many uNK cells exist during mid pregnancy, although they show a sudden decrease during late pregnancy and almost disappear before delivery. Our previous study indicated that uNK cells showed clear apoptotic morphology during late pregnancy. Therefore, the present study was carried out to define the involvement of Fas ligand (FasL) and Fas in apoptosis induction of uNK cells. Immunohistochemical analyses revealed that uNK cells expressed FasL in the cytoplasmic granules and Fas on the cell membrane during late pregnancy. In lpr/lpr mice, which genetically lack Fas, many uNK cells were clearly observed during late pregnancy compared with wild-type mice, and moreover uNK cells still existed at day-18 of pregnancy, although there were few in wild-type mice during the same period. In the experiment of in vitro culture, uNK cells derived from wild-type placenta showed chromatin condensation and DNA fragmentation frequently following the anti-Fas antibody treatment, as compared with the control. From these results, it is suggested that FasL and Fas-dependent apoptosis regulates cell appearance of uNK cells in the mouse pregnant uterus. 相似文献