共查询到16条相似文献,搜索用时 15 毫秒
1.
Bartosz WOJCIECHOWICZ Genowefa KOTWICA Justyna KOLAKOWSKA Anita FRANCZAK 《The Journal of reproduction and development》2013,59(1):49-58
Steroid hormones are produced by the porcine uterus. We hypothesized that the uterus in
pigs possesses active 3β-hydroxysteroid dehydrogenase/Δ5-Δ4
isomerase (3β-HSD) responsible for progesterone and androstenedione production, that
uterine steroids may supplement the amount of steroid hormones produced by embryos and
corpus luteum and that these steroids are necessary for maintenance of pregnancy. In this
study, we examined 1) endometrial and myometrial expression of 3β-HSD
mRNA, 2) uterine 3β-HSD protein activity and 3) in vitro production of
A4 and P4 by uterine slices harvested from pigs on days 10 to 11,
12 to 13 and 15 to 16 of pregnancy and the estrous cycle. The expression of
3β-HSD and the presence and activity of 3β-HSD protein were different
in the endometrium and the myometrium during the examined periods of pregnancy and the
estrous cycle. Production of A4 by the endometrium and myometrium was highest
on days 12 to 13 of pregnancy and the estrous cycle. Endometrial secretion of
P4 did not differ in the course of early pregnancy and on the respective days
of the estrous cycle. The gravid myometrium was the highest source of P4 in
pregnant pigs on days 12 to 13. The release of P4 by the cyclic myometrium rose
during the examined days of the estrous cycle. The steroidogenic activity of the uterus,
as described in this study, may support early pregnancy or the luteal phase of the estrous
cycle in pigs. 相似文献
2.
Yuko TAJIMA Kaori MAEDA Tadasu K. YAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):45-51
One hundred and twenty
stranding events of Stejneger’s beaked whales were reported in Japan between 1999 and
2011. The purpose of this study is to introduce pathological data and to discuss probable
causes of death for 44 Stejneger’s beaked whales among them. The significant pathological
findings were the pulmonary edema, parasitic granulomatous nephritis, emaciation,
amyloidosis, suppurative bronchopneumonia and so on. The probable causes of death were
categorized as noninfectious in 43 of the cases, which included drowning, starvation and
secondary amyloidosis. One individual was diagnosed with septicemia, which was the only
example of an infectious disease. Because we could not always perform advanced analyses,
such as microbiology tests, biotoxin examinations or contaminant analyses, the finality of
our findings may be impaired. However, the present study has broad implications on the
causes of death of Stejneger’s beaked whales of the seas around Japan, which are valuable
for the future studies and for the detection of emerging diseases. 相似文献
3.
4.
Yurie KAWASAKI Yuka AOKI Fumie MAGATA Akio MIYAMOTO Chiho KAWASHIMA Takuo HOJO Kiyoshi OKUDA Koumei SHIRASUNA Takashi SHIMIZU 《The Journal of reproduction and development》2014,60(3):173-178
The present study aimed to assess the effect of polymorphisms in the tumor necrosis factor α (TNF-α) promoter (A/A, A/G and
G/G) and exons (T/T, T/C and C/C) on immune function and reproductive performance in dairy cows. The occurrence of the first
postpartum ovulation within 3 weeks in the cows with the TNF-α promoter A/G and G/G genotypes was higher than in the A/A
group. Among the different TNF-α exon genotypes, the occurrence of early first postpartum ovulation was higher in the T/C and
C/C genotype groups than in the T/T group. Single nucleotide polymorphisms (SNPs) in the TNF-α gene did not affect the rate
of artificial insemination (AI) or duration from parturition to next conception (days open). The apoptosis rate of
polymorphonuclear leukocytes (PMNs) did not differ among the TNF-α promoter genotypes, but the PMN transmigration rate was
significantly higher for the A/A and A/G genotypes than for the G/G genotype. Interleukin 8 (IL-8) mRNA expression in PMNs
and peripheral blood mononuclear cells (PBMCs) before culture was significantly higher for the A/A genotype compared with the
G/G genotype. There were no significant differences between the genotypes in the mRNA expression of TNF-α, IL-6, IL-1β, and
toll-like receptor 4 (TLR4) in PMNs and PBMCs before and 4 h after culture. IL-8 and IL-1β production by PBMCs cultured for 4
h was significantly higher for the animals with the A/A genotype than for those with the G/G genotype. On the other hand, no
significant difference was observed in IL-8 and IL-1β production by PMNs among different TNF-α genotypes. Taken together,
these results suggest that SNP in the TNF-α gene affects immune function and reproductive performance in dairy cows. 相似文献
5.
Toshiaki SUMIYOSHI Tomomi TANAKA Hideo KAMOMAE 《The Journal of reproduction and development》2014,60(2):106-114
Lactating Holstein-Friesian cows kept in tie-stall barn were used as subjects in this
study. Rectal examination, ultrasonography and blood sampling were conducted every other
day and then daily after the day on which diameter of the corpus luteum decreased. After
the luteal diameter decreased for 2 consecutive days, rectal and ultrasound examinations,
blood sampling, and observation of estrous signs were conducted at 6-h intervals. Most of
the estrous signs became obvious with the increase in estradiol-17β (E2) and
became most remarkable 24 to 30 hours before ovulation, at which point the E2
peak and luteinizing hormone (LH) surge were achieved, and then weakened which progression
to ovulation. The correlation between the intensity of four estrous signs (hyperemia and
swelling of the intravaginal part of the uterus, opening of the external uterine orifice
and viscosity of the cervical mucus) and the plasma E2 concentration was higher
than that of three estrous signs (swelling of the vulva, contraction of the uterus,
diameter of uterine horn) and the plasma E2 concentration. The relaxation of
the intravaginal part of the uterus showed a unique change compared with the other estrous
signs, and it became most obvious 6, 12 and 18 h before ovulation; this obviously relaxed
period was consistent with the generally accepted theoretical optimal time for artificial
insemination (AI), i.e., 6 to 24 h after initiation of estrus. These results suggest that
observation of estrous signs by vaginoscopic examination gave useful information for
detection of the optimal timing of AI in the periovulatory period in lactating dairy cows
kept in a tie-stall barn. 相似文献
6.
7.
Agnieszka BLITEK Ewa MORAWSKA-PUCINSKA Magdalena SZYMANSKA Jolanta KIEWISZ Agnieszka WACLAWIK 《The Journal of reproduction and development》2013,59(6):512-519
Transforming growth factor (TGF) β and its receptors are expressed at the
conceptus-maternal interface during early pregnancy in the pig. The present studies
were conducted to examine: (1) the effect of conceptus products on TGFβ1 mRNA
expression and protein concentration in the porcine endometrium using in
vivo and in vitro models, and (2) the effect of TGFβ1 on
proliferation of porcine trophoblast cells in vitro. During
in vivo experiments, gilts with one surgically detached uterine
horn were slaughtered on days 11 or 14 of the estrous cycle and pregnancy. For
in vitro studies, endometrial explants and luminal epithelial
(LE) cells co-cultured with stromal (ST) cells were treated with conceptus-exposed
medium (CEM). Moreover, porcine trophoblast cells were treated with TGFβ1, and the
number of viable cells was measured. On day 11, the presence of conceptuses had no
effect on TGFβ1 mRNA expression, but decreased the TGFβ1 protein concentration in the
connected uterine horn compared with the detached uterine horn. In contrast to day
11, on day 14 after estrus, TGFβ1 mRNA expression and protein content in the
endometrium collected from the gravid uterine horn were greater when compared with
the contralateral uterine horn. The treatment of endometrial slices with CEM resulted
in greater TGFβ1 mRNA expression and protein secretion. LE cells responded to CEM
with an increased TGFβ1 mRNA level. Moreover, TGFβ1 stimulated the proliferation of
day 14 trophoblast cells. In summary, porcine conceptuses may regulate TGFβ1
synthesis in the endometrium at the time of implantation. TGFβ1, in turn, may promote
conceptus development by increasing the proliferation of trophoblast cells. 相似文献
8.
9.
Tsutomu TSUKADA Anna Yumiko KOJIMA Kunitada SATO Masaharu MORIYOSHI Masanori KOYAGO Yutaka SAWAMUKAI 《Journal of Equine Science》2008,19(2):31-34
The concentrations of androstenedione, estradiol-17β, progesterone and PGF2α
contained in the follicular fluid produced by the follicles in collected ovaries of mares
that have had estrous phase during the breeding season were measured and analyzed the
relation between the growth stage of follicles and the hormone levels in the follicular
fluid. An ultrasonographic diagnostic instrument was used to measure the diameter of the
follicles in order to categorize the follicles into three groups the following: 8 small
follicles (from 1.0 to less than1.5 cm), 8 medium follicles (from 1.5 to less than 3.0
cm), and 8 large follicles (from 3.0 to 5.0 cm), respectively. The analysis of the
follicular fluid in ovaries of estrous mares showed that the concentrations of
androstenedione were significantly higher in the medium or large follicles than in the
small follicles and the concentrations of estradiol-17β were significantly higher in
larger follicles than in the small or medium follicles (P<0.05). The concentrations of
progesterone and PGF2α, on the other hand, did not significantly vary
regardless of follicluar size. In the follicles within the mare ovaries that have had
estrous stage, the concentrations of the hormones related the ovulation, namely
androstenedione and estradiol-17β, were higher with larger follicles. 相似文献
10.
Padet TUMMARUK Sawang KESDANGSAKONWUT 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1095-1100
The objective of the present study was to determine the number of ovulations in culledLandrace × Yorkshire (LY) crossbred gilts in the tropics associated with age, body weightand growth rate. The genital organs from 316 gilts were examined for gross abnormalities,and those with normal cyclic ovaries (n=155, 307 ± 4.1 days of age, 148 ± 1.6 kg bodyweight) were included in the analyses. Number of ovulations was defined by a count of thecorpora lutea (CL) from both ovaries. On average, the number of ovulations in LY gilts was15.9 ± 0.3 (range 4 to 27). The number of ovulations correlated with the body weight(r=0.31, P<0.001) and growth rate (r=0.20, P=0.015)of the gilts, but not with their age (P>0.05). Gilts with a bodyweight of 141 to 150 kg (17.0 CL, n=31) ovulated more than those with a body weight ≤130kg (14.1 CL, P=0.014, n=23). In conclusion, both the body weight andgrowth rate of the gilts were significantly correlated with the number of ovulations. Themaximum number of ovulations was found in gilts at a body weight of above 141 kg. 相似文献
11.
In China, the first Przewalski’s horse (Equus przewalskii) group was released in
Kalamaili Ungulate Protected Area in Xinjiang, in August 2001. The objective of this study
was to investigate reproduction and development of released Przewalski’s horses in
Xinjiang, China from 2002 to 2006. Twenty-four descendants were naturally born, average
reproduction rate was 38.7%, and average survival rate of foals was 69.1% in this interim.
Frequent alternation of the leading stallion and infertility in female horses due to
environmental factors were main causes for the low reproduction rate. The infant mortality
rate of released Przewalski’s horses was 25.0%, and 83.3% of death in infants was due to
the leading stallion infanticide. The released Przewalski’s horses exhibited seasonal
breeding, 70.8% of infants were born in May and June. The fertility rates were 8.3% in
April and 37.5% in May, which were lower compared to those of the captive Przewalski’s
horse groups (18.3% and 44.3%, respectively). Furthermore, the fertility rate in June was
33.3% and higher than the captive groups (18.3%). These findings showed that the breeding
peak of the released Przewalski’s horse groups was later than the captive groups, and
suggested that the altered survival environment and food supplies were the main reasons
contributing to the delayed breeding peak. 相似文献
12.
Mariko KUSE Hwa-Yong LEE Tomas J. ACOSTA Takuo HOJO Kiyoshi OKUDA 《The Journal of reproduction and development》2013,59(4):346-352
Cortisol (Cr), the most important glucocorticoid (GC), is well known to suppress uterine
prostaglandin F2α (PGF) production. However, the details of the regulatory mechanisms
controlling the cyclic changes in endometrial PGF production remain unclear. Here we
investigated the expression of the GC receptor (GC-Rα), the actions of cortisol throughout
the estrous cycle and the regulatory mechanism of GC-Rα in the bovine endometrium. The
levels of GC-Rα protein were greater at the mid-luteal stage (Days 8–12) than at the other
stages. Cr more strongly suppressed PGF production at the mid-luteal stage than at the
follicular stage. GC-Rα expression was increased by progesterone (P4) but decreased by
estradiol-17β (E2) in cultured endometrial stromal cells. The overall results suggest that
ovarian steroid hormones control the cyclic changes in endometrial PGF production by
regulating GC-Rα expression in bovine endometrial stromal cells. 相似文献
13.
Genetic structure of the Amur tiger (Panthera tigris altaica) population: Are tigers in Sikhote‐Alin and southwest Primorye truly isolated? 下载免费PDF全文
Pavel A. SOROKIN Vyatcheslav V. ROZHNOV Anna U. KRASNENKO Victor S. LUKAREVSKIY Sergey V. NAIDENKO Jose A. HERNANDEZ‐BLANCO 《Integrative zoology》2016,11(1):25-32
We used molecular genetic analyses to noninvasively identify individual Amur tigers and define subpopulations of tigers in the Russian Far East. We identified 63 individuals after genotyping 256 feces, 7 hair and 11 blood samples collected within southern, central and northern Sikhote‐Alin, as well as Southwest Primorye. Analysis of nuclear DNA at 9 microsatellite loci demonstrated greater genetic similarity between animals from southern and northern Sikhote‐Alin (some 500 km apart) than between animals from Ussuriskii State Nature Reserve and Southwest Primorye (less than 10 km apart at their nearest point), suggesting that a true barrier exists preventing movements of tigers between Southwest Primorye and the southern Sikhote‐Alin Mountains. 相似文献
14.
Wageh Sobhy DARWISH Yoshinori IKENAKA Alaa Eldin MORSHDY Kamal Ibrahim ELDESOKY Shouta NAKAYAMA Hazuki MIZUKAWA Mayumi ISHIZUKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):351-354
The aim of this study was to estimate total carotenoids, β-carotene and retinol concentrations in the liversand muscles of some ungulates (cattle, buffalo, sheep, goats and horses) in comparison with the Wistar rats asa control. Cattle and horses had the highest contents of total carotenoids and β-carotene. Unexpectedly, sheepwas the highest accumulator of retinol with a mean concentration of 203 ± 23.34 µg/g, whilethe least accumulator was buffalo, having a mean value of 58.28 ± 13.77 µg/g. Livers hadhigher contents of the examined phytochemicals than muscles. Consumption of these tissues may provide humanwith some needs from these important phytochemicals, though ingestion of livers, especially that of the sheep,is not advisable for the pregnant women. 相似文献
15.
16.
The objective of this study was to compare the biomechanical properties in a single cycle axial loading test and the types of failures in two constructs (a 3-hole 4.5-mm dynamic compression plate (DCP) and 7-hole 5.5-mm Y locking compression plate (Y-LCP)) in equine proximal interphalangeal joint (PIJ) arthrodesis. One limb in each pair was randomly assigned to PIJ arthrodesis using a 3-hole 4.5-mm DCP combined with two transarticular 5.5-mm cortical screws, whereas the contralateral limb was submitted to PIJ arthrodesis using a 7-hole Y-shaped 5.0-mm LCP in conjunction with one transarticular 4.5-mm cortical screw inserted through the central plate hole. Cortical screws were inserted in lag fashion. Constructs were submitted to a single axial load cycle to failure. Construct stiffness, load, and deformation were analyzed. Dynamic compression plate and Y-LCP arthrodesis constructs did not differ significantly and were equally resistant to axial loading under the conditions studied (DCP and Y-LCP group stiffness, 5685.22 N/mm and 6591.10 N/mm, respectively). Arthrodesis of the PIJ using a DCP and two transarticular 5.5-mm cortical screws or a Y-LCP yielded biomechanically equivalent outcomes under the test conditions considered. However, Y-LCP provides less impact in the palmar/plantar bone. Application of Y-LCP with unicortical screws has equivalent biomechanical characteristics of DCP and may be a safe option for PIJ arthrodesis, where potential trauma secondary to applying bicortical screws in the palmar/plantar aspect of the pastern can be avoided. 相似文献