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1.
To test the hypothesis that placental lactogen (PL) is a Immoral regulator of fetal growth, six singleton sheep fetuses received a continuous intravenous fusion of 1.2 mg/d of purified ovine PL (oPL) for 14 d, beginning on Day 122 of gestation. The plasma concentration of oPL was approximately four-fold higher in infused fetuses than in six control fetuses that received a continuous infusion of saline. The circulating insulin-like growth factor 1 (IGF-1) concentration was also significantly elevated in PL-infused fetuses (43.1 ± 1.7 vs. 31.9 ± 4.l ng/ml; P < 0.05). Animals were slaughtered on Day 136, and the placenta and all major fetal tissues were dissected, weighed, and subsampled for chemical analysis. Fetal weight and crown-rump length were not significantly affected by treatment; however, the aggregate weight of the brain, liver, lungs, and heart tended to be larger (85.3 ± 2.1 vs. 79.9 ± 1.5 g/kg fetus; mean ± SE, P = 0.07) and the thyroid gland was smaller (0.18 ± 0.l vs. 0.26 ± 0.02 g/kg fetus; P < 0.05) in the PL-infused fetuses. The livers of the PL-infused fetuses had also accumulated additional glycogen (13.1 ± l.7 vs. 8.4 ± 0.7 g; P < 0.05). In late gestation, PL within the fetal compartment increases fetal plasma IGF-1 concentration and hepatic glycogen deposition and may affect the growth of several vital organs.  相似文献   

2.
The concentration of ovine placental lactogen (oPL) in maternal plasma varies with litter size and nutritional status, making it difficult to compare these concentrations across studies. In this study, 27 Dorset and Finn-Dorset crossbred ewes with litters of known size and gestational age were used to relate concentrations of oPL in maternal plasma to placental and fetal weights. Fetal oPL concentrations also were correlated to these variables in 12 chronically catheterized singleton fetuses. The concentration of oPL in maternal plasma increased with increasing placental weight across litter sizes ranging from 1 to 3 (r = .716). When expressed per gram of placenta, oPL was greater (P less than .05) in those ewes carrying multiple fetuses. There was no correlation between maternal and fetal oPL in time-matched samples or in average values between individuals for ewes carrying singleton pregnancies. Within the singleton group, placental weight and fetal weight were well correlated (r = .761), as were the concentration of fetal plasma oPL and fetal weight (r = .699). Placental weight plus fetal oPL could explain 81% of the variation seen in fetal weight. These results imply that maternal and fetal oPL release are controlled independently and that fetal oPL affects fetal growth by a mechanism not directly related to placental size.  相似文献   

3.
For cows on d 137 (n = 6), 180 (n = 8), 226 (n = 9) and 250 (n = 5) of gestation (Exp. 1), concentrations of insulin and glucose were two- to three-fold less (P less than .01) in fetal venous plasma than in uterine arterial plasma. Concentrations of growth hormone, conversely, were 10- to 20-fold greater (P less than .01) in fetal venous than in uterine arterial plasma. Concentrations of insulin and glucose in maternal and fetal plasmas and concentrations of growth hormone in maternal plasma did not vary with stage of gestation. Concentrations of growth hormone in fetal venous plasma, however, were greater on d 226 and 250 than on d 137 and 180. For cows (n = 6) on d 198 of gestation (Exp. 2), concentrations of insulin and glucose in maternal and fetal plasmas and of growth hormone in maternal plasma remained relatively constant in samples collected every 30 min for 3 h. In contrast, growth hormone concentrations in fetal venous plasma were highly variable and appeared to be episodic, with pulses of 10 to 60 ng/ml in amplitude. No significant correlations were found among concentrations of insulin, glucose and growth hormone in fetal venous plasma. When samples were collected every 15 min for 4 h from cows (n = 5) on d 198 of gestation (Exp. 3), episodes of growth hormone in fetal venous plasma were irregular in amplitude and frequency.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
Serum samples and BW were obtained from 2-yr-old beef heifers, pregnancy with either single (SF, n = 12) or twin (TF, n = 7) fetuses, at 7-d intervals from d 190 of gestation until calving. Serum insulin-like growth factor I (IGF-I) concentrations of SF heifers gradually declined from d 190 (69.9 +/- 1.0 ng/ml) to d 263 (55.6 +/- .8 ng/ml), then exhibited a slight increase by d 277 (63.4 +/- 1.1 ng/ml). Serum IGF-I concentrations of TF heifers essentially paralleled, yet were lower (P less than .05) than, concentrations in SF heifers for all days tested except d 197 and 205. The SF heifers pregnant with heifer fetuses (n = 6) had higher IGF-I concentrations (P less than .1) than heifers pregnant with bull fetuses (n = 6) for all days tested except d 214 and 235. Instantaneous absolute growth rate (IGR) of SF heifers declined from 1.485 kg/d at d 190 to .257 kg/d by d 277. Rate of decline in IGR of TF heifers was much greater (P less than .0001). Correlations between serum IGF-I concentrations and IGR for SF and TF heifers were .79 (P less than .001) and .59 (P less than .05), respectively. These data suggest that number and sex of fetus influence maternal concentrations of IGF-I and that the combined growth rate of the dam and conceptus during gestation is related to serum IGF-I concentration.  相似文献   

5.
An experiment was conducted to investigate the temporal relationship of peripheral estrone (E1) concentration to changes in the size of the pelvic opening preceding and immediately following parturition. Twenty-six multiparous beef cows were observed from approximately 50 d prepartum to 7 d postpartum. Blood samples were collected at 7 d intervals preceding calving and at 1, 3 and 7 d following for E1 quantitation. Estimates of pelvic opening area were made at the time of blood sampling. Peripheral E1 concentrations were elevated beginning at approximately 25 d prepartum. Dams bearing male fetuses had greater (P less than 0.01) concentrations of E1 than did dams with female fetuses. Calf birth weight was correlated (r = 0.44, P less than 0.01) with E1 levels from 10 d prepartum through parturition. Postpartum pelvic area was greater for cows giving birth to male calves, with no significant differences for calf birth weights by sex. Correlations were observed between E1 concentration, and pelvic area measured from 50 d prepartum to 7 d postpartum (r = 0.26, P less than 0.01), 10 d prepartum to calving (r = 0.42, P less than 0.01), and from calving to 7 d postpartum (r = 0.33, P less than 0.01). Percentage increase in E1 concentration from 50 d prepartum to calving was significantly correlated (r = 0.75, P less than 0.01) to percentage pelvic area increase over the same period. A correlation also exists between maternal E1 concentrations and fetal sex and pelvic area. In summary, the increased estrogen concentrations in cows with male calves may facilitate pelvic spread, resulting in a larger pelvic opening.  相似文献   

6.
The biochemical properties of ovine placental lactogen (oPL) have been previously determined following purification, which has yielded various results. To clarify the properties of oPL prior to purification, oPL was examined in solubilized fetal cotyledonary tissue (d 100 of gestation) or conditioned culture medium by electrophoretic, immunoblotting and immunoprecipitation techniques. In cotyledonary tissue or conditioned culture medium, oPL has an apparent molecular weight (Mr) of 22,000 with an isoelectric point (pI) of 9.2. Incorporation of [3H]-glucosamine or [3H]-mannose into immunoreactive oPL could not be detected, nor did the presence of tunicamycin in explant culture medium alter the apparent Mr of oPL. In vitro translation of d 100 fetal cotyledonary mRNA, followed by immunoprecipitation, provided evidence that pre-oPL has an apparent Mr of 25,000. The size of oPL mRNA was determined to be approximately 1,350 base pairs by Northern hybridization procedures using an oligonucleotide probe which was generated from oPL amino acid sequence data. These experiments suggest that the only intracellular processing oPL undergoes is removal of a amino-terminal signal sequence. We conclude that oPL is synthesized and secreted as a single nonglycosylated-basic protein, at a time during gestation when circulating oPL is elevated.  相似文献   

7.
Ovine placental lactogen (oPL) exerts actions in sheep and rodent fetal tissues that growth hormone (GH) does not. However, in postnatal tissues, both oPL and GH possess these activities. Although a high-affinity binding site for oPL in ovine fetal liver has been reported, some investigators believe this to be the GH receptor. It was our objective to discriminate between oPL and GH binding to fetal liver microsomes using competitive saturation analyses. Microsomal membranes from fetal liver (Days 60, 90, 105, 120, and 135 of gestation) and postnatal liver (1 wk of age) were incubated with increasing amounts of [125I]oPL in the absence or presence of a 100-fold molar excess of unlabeled oPL. Saturable binding of [125I]oPL was observed with fetal liver and postnatal liver microsomes. The Kd of the oPL-binding site in fetal liver was 122.1 ± 8.2 pM (mean ± standard error), and receptor concentrations remained relatively constant (9.8 ± 1.1 fmol/mg of membrane protein) across gestation. The highest concentration of oPL binding was detected in 1-wk postnatal liver microsomes (53.0 fmol/mg of membrane protein). Saturation analyses using [125I]GH and [125I] prolactin (PRL) were also conducted with fetal liver membrane preparations. Although specific binding for these two radiolabeled ligands was observed in control tissues, no specific binding was observed in fetal liver. These data are in agreement with earlier reports that a high-affinity binding site for oPL exists in fetal tissues. The fact that saturable binding could not be demonstrated for either GH or PRL with fetal liver microsomes contradicts recent suggestions that oPL is binding the GH receptor.  相似文献   

8.
The within-litter relationship of fetal weight to fetal serum albumin and alpha-fetoprotein (AFP) was investigated at d 30 to 40, 45 to 50, 50 to 60, 75 to 85 and 90 to 105 of gestation in swine. Regression equations were calculated on individual litters and regression coefficients pooled across litters within each gestational age group. Coefficients for the regression of albumin on fetal weight (microgram . ml-1 . g fetus-1) were significant over all groups and ranged from 22.5 +/- 6.6 to d 45 to 50 to .7 +/- .2 at d 95 to 105. There was no significant relationship between AFP levels and fetal weight at any gestational age. Unilateral ovariectomy-hysterectomy was performed before mating to study effects of uterine crowding on the relationship of fetal weight to AFP and albumin. Although the total number of ovulations was not different from controls, this treatment resulted in only about 1.3 more fetuses/uterine horn compared with controls at either d 40 or 60 of gestation. Fetal weights in crowded litters were not different from controls. However, AFP levels in fetuses from crowded litters were lower than in control fetuses at d 40 (4.5 +/- .1 vs 6.7 +/- .5 mg/ml). Albumin levels in crowded fetuses were significantly lower than in controls at d 60 (342 +/- 50 vs 653 +/- 41 micrograms/ml). Because none of these differences in albumin or AFP could be attributed to variation in fetal weight or fetal number at the time of sample collection, it is possible that more extreme uterine crowding earlier in development resulted in these differences. These results demonstrate that fetal serum albumin concentrations are related to fetal weight when analyzed on a within-litter basis and that unilateral ovariectomy-hysterectomy may affect serum concentrations of both AFP and albumin early in fetal development. Future studies involving the regulation of synthesis of these proteins at the cellular level during development should provide information as to how factors affecting overall fetal growth and development influence the expression of a single gene. Previously, such markers that are amenable to study early in development have been lacking.  相似文献   

9.
Crowded uterine conditions were induced by unilateral hysterectomy-ovariectomy (UHO) in 42 gilts to determine the effect of recombinant porcine somatotropin on fetal and placental growth. Gilts were randomly assigned across three replicates to one of three treatments: Control (C; n = 14), daily injections of 1 mL saline from d 0 to 64 of gestation, Early (E; n = 12), 5 mg of rpST/d from d 0 to 30, followed by 1 mL saline from d 31 to 64, and Late (L; n = 16), 1 mL saline/d from d 0 to 29, followed by 5 mg of rpST/d from d 30 to 64 of gestation. Blood was collected from each gilt via jugular venipuncture at d 0 and every 15 d thereafter. Gilts were hysterectomized on d 65 of gestation. Length of placental attachment and fetal crown-rump length were measured. Placentas and fetuses were weighed. Placental length, wet weight, and dry weight were recorded. Treatment with rpST (either E or L) increased (P < 0.0001) maternal plasma IGF-I concentrations relative to controls. Treatment with rpST did not affect placental wet weight or placental DNA content. However, E and L treatments increased the percentage of placental protein (P = 0.01) and placental dry matter (P = 0.10) and increased contact area of uterine-placental interface (P = 0.01). Despite changes in placental composition and morphology, weights of fetuses collected from L-treated gilts did not differ from controls, whereas weights of fetuses collected from E-treated gilts tended to be less than controls (P < 0.06). Administration of rpST increased maternal IGF-I concentrations and placental surface area but failed to increase fetal growth in the UHO model. Therefore, mechanisms that are independent of maternal IGF-I or placental contact area may control early fetal growth under crowded uterine conditions.  相似文献   

10.
Holstein heifers (n = 21) were balanced across sires and assigned to three service-sire-breed groups in which heifers were inseminated artificially to either purebred Angus (n = 7), Holstein (n = 7) or Brahman (n = 7) bulls. Semen from four bulls was used for each service sire-breed group. Blood samples were collected from a jugular vein thrice weekly from d 160 to 265 of pregnancy, daily thereafter until 15 d postpartum, and then thrice weekly until d 60 postpartum. Concentrations of progesterone, estrone, estradiol, and estrone sulfate from 23 d prepartum to parturition, and of 15-keto-13,14-dihydro-prostaglandin F2 alpha (PGFM) from 2 d prepartum to d 15 postpartum were measured by radioimmunoassay. Heifers within the Brahman-service-sire group had longer gestations (P less than .05) than those of Holstein- or Angus-service-sire groups (285.0 vs 278.7), 279.0 d). Calf birth weight was lower (P less than .05) in Angus- than Holstein- and Brahman-service-sire groups (30.6 vs 36.1, 43.4 kg). Daily trends of prepartum maternal progesterone concentrations were approximately 1 ng/ml lower (P less than .01) in Angus- than Holstein- or Brahman-service-sire groups until luteolysis occurred. Heifers bearing crossbred Angus conceptuses had lower daily trends of prepartum estrogens concentrations (P less than .01), whereas heifers of the Holstein- and, even more dramatically, of the Brahman-service-sire groups had a higher magnitude and greater rise of plasma estrogens concentrations between d -10 and -1 prepartum (less than .01). Postpartum mean concentrations (P less than .05) and response curves of PGFM were lower (P less than .01) in the Angus- than in the Holstein- or Brahman-service-sire groups. Calf birth weights were correlated with least-squares means for maternal concentrations of prepartum estrone (r = .57), estradiol (r = .59) and estrone sulfate (r = .64) and postpartum maternal concentrations of PGFM (r = .56). Functional responses of the conceptus (e.g., estrogens) and maternal units (e.g., progesterone and PGFM) were influenced by conceptus genotype during the periparturient period.  相似文献   

11.
Embryonic and fetal mortality reduce lambing rates and litter sizes, thus contributing to economic losses in the sheep industry. In the current study, the timing of late embryonic and fetal loss in ewes and the factors with which these losses were associated were examined. Ewes lambing and lambs born were compared with pregnancy diagnosis and counts of embryos by ultrasonography near d 25, 45, 65, or 85 of gestation. Approximately 19.9% of the ewes experienced late embryonic loss, fetal loss, or both; and 21.2% of the embryos or fetuses were lost from d 25 to term. Potential offspring were lost throughout gestation; 3.7% of embryos from d 25 to 45, 4.3% of fetuses from d 45 to 65, 3.3% from d 65 to 85, and 11.5% from d 85 to parturition; thus, approximately 3 to 4% of the potential offspring were lost for each 20-d period of pregnancy beyond d 25. A greater proportion of ewes lost one (36.7%) rather than all (20.5% single; 3.8% multiple) embryos or fetuses. The patterns of loss were similar in ewes mated during the anestrous season and the transitional period and did not vary with service period within breeding season or method of synchronization of estrus. Late embryonic or fetal losses were not related to the temperature-humidity index. Maternal serum collected near d 25, 45, 65, or 85 of gestation was assayed for concentrations of progesterone, estradiol-17beta , and vascular endothelial growth factor (VEGF). The proportions of embryos or fetuses lost were associated with breed type (P < 0.05), as were concentrations of progesterone (P < 0.01), estradiol (P < 0.05), and VEGF (P < 0.01). The relationships of loss or retention of pregnancy to hormonal variables at the 4 stages studied were limited. Complete and partial losses increased rapidly as maternal progesterone at d 25 decreased below 2 ng/mL (P < 0.05). Survival of fetuses within a litter from d 25 to 65 was greater for ewes with medium concentrations of VEGF near d 25 and from d 65 to parturition was greater for ewes with high concentrations of VEGF near d 45 (P < 0.05). In summary, late embryonic or fetal losses occurred from d 25 throughout gestation and varied with breed type and with concentrations of progesterone in maternal serum on d 25.  相似文献   

12.
This study determined ultrasonographic parameters of fetuses and uterine adnexa in late pregnancy in normal, cloned, and high-risk pregnancies in relation to perinatal and neonatal outcome. Ten cows with normal pregnancies (CONTROL, mean pregnancy length 273 d), 10 sick cows with potentially compromised pregnancies (HIGH-RISK, mean pregnancy length 267 d), and 10 heifers with cloned pregnancies (CLONED, mean pregnancy length 274 d) were examined at more than 260 d of gestation. There was no difference in mean fetal heart rates among the groups. The cloned calves were heavier (57 ± 8 kg) than calves from CONTROL group (36 ± 7 kg), and calves from HIGH-RISK group (37 ± 13 kg) (P = 0.003). The diameter of the thoracic aorta was positively correlated (R = 0.62) with fetal birth weight in the CONTROL group (P = 0.01). Fetal activity was not associated with survival. The results suggest that transabdominal ultrasonographic assessment of the fetal well-being may serve as a potential tool for evaluation of the fetoplacental unit.  相似文献   

13.
To determine the effects of maternal Se intake and plane of nutrition during mid or late gestation or both on AA concentrations and metabolite concentrations in the dam and fetus, pregnant ewe lambs (n = 64) were assigned to 1 of 8 treatments arranged in a 2 × 2 × 2 factorial array: Se level [initiated at breeding; adequate (ASe; 3.05 μg/kg of BW) or high (HSe; 70.4 μg/kg of BW)] and nutritional level [100% (control; CON) or 60% (restricted; RES) of NRC recommendations] fed at different times of gestation [d 50 to 90 (mid) or d 91 to 132 (late)]. A blood sample was obtained from each ewe and fetus on d 132 of gestation and used to measure circulating concentrations of glucose, NEFA, blood urea N, and AA. The late RES ewes and their fetuses had less (P ≤ 0.03) circulating glucose compared with late CON ewes and fetuses at d 132; however, no effect (P ≥ 0.14) of diet on the fetal:maternal glucose concentration ratio was observed. Late RES ewes had a smaller (P = 0.01) fetal:maternal NEFA ratio compared with late CON ewes. Ewes fed ASe had a greater (P = 0.01) fetal:maternal blood urea N ratio compared with HSe ewes. Fetal:maternal ratios of total circulating AA, total essential AA, and total nonessential AA were each affected (P ≤ 0.03) by the combination of Se treatment and late gestation nutritional level.  相似文献   

14.
This study presents serum concentrations of pregnancy‐associated glycoprotein (PAG), oestrone sulphate (E1‐S) and progesterone (P4), and the effects of some dam and foetus‐related factors on these profiles during gestation in Borana and crossbred cattle. The PAG concentrations at 4th week post‐conception ranged from 1.5–5.5 and 2.1–4.7 ng/ml in Borana (n = 6) and crossbred (n = 8) cattle, respectively. The mean PAG concentrations increased progressively from 4th to 33rd week of gestation (from 3.3–173 ng/ml for Borana and 4.2–240 ng/ml for crossbred cattle) and reached peak around calving. Breed, parity status, dam body weight, foetal sex and foetal birth weight significantly influenced the PAG concentrations. After delivery, the PAG concentrations declined steadily to 5.7 ng/ml in Borana (n = 7) and 3.9 ng/ml in crossbred (n = 6) cattle 10 weeks post‐partum. The serum E1‐S concentrations at 17th week of pregnancy ranged from 0.3–2.6 and 0.9–5.7 ng/ml in Borana (n = 8) and crossbred (n = 9) cattle, respectively. The mean E1‐S concentrations increased progressively from 17th to 33rd week of gestation (from 1.1–4.6 ng/ml for Borana and 2.7–10.8 ng/ml for crossbred). Breed, parity status, dam body weight and foetal sex significantly influenced E1‐S concentrations. The P4 concentrations at 4th week of pregnancy ranged from 3.2–5.1 and 1.7–8.9 ng/ml in Borana (n = 6) and crossbred (n = 8) cattle, respectively. The P4 level remained elevated throughout pregnancy. This study indicated that the serum PAG and P4 concentrations at 4th and E1‐S approximately 17th week of pregnancy were above the cut‐off value for pregnancy test and the hormonal profiles observed were comparable to the previous reports. Furthermore, the PAG and E1‐S profiles were considerably influenced by factors such as breed, weight and parity status of the dam, and foetal sex and foetal birth weight (only PAG).  相似文献   

15.
Concentrations of ovine placental lactogen (oPL) were measured in the peripheral plasma of six ewes after the removal of fetuses (in four ewes) or after the intrauterine death of one of twin fetuses (in two ewes). Concentrations of oPL decreased after fetectomy or intrauterine fetal death, indicating that a living fetus is essential to the sustained secretion of oPL.  相似文献   

16.
Growth and compositional changes of fetal tissues in pigs   总被引：2，自引：0，他引：2  
Three hundred twenty fetuses were obtained from 33 pregnant gilts (Camborough-22, Pig Improvement Co.) to determine rates of nutrient deposition in fetal tissues and to estimate nutrient requirements for fetal growth. Pregnant gilts were fed an equal amount of a gestation diet (2.0 kg/d; as-fed basis), and were slaughtered at d 0, 45, 60, 75, 90, 102, or 110 of gestation (n = 3 to 6 per day). Fetuses were dissected into carcass and individual tissues (including gastrointestinal tract, liver, lung, heart, kidney, spleen [> or = d 75]), and partial placental collection was made for chemical analysis. Fetal tissues were weighed and analyzed for DM, ash, CP, and crude fat. Regression equations were obtained to explain the weight and compositional changes of individual tissues during gestation. Weights of the fetus, carcass, gastrointestinal tract, liver, heart, lung, and kidney increased cubically (P < 0.001), whereas brain weight increased linearly (P < 0.001) as gestation progressed. Fetal protein and fat contents increased quadratically (P < 0.001) as gestation progressed (R2 = 0.906 and 0.904, respectively). Changes in fetal protein and fat contents fit a multiphasic regression that consisted of two linear equations (P < 0.001, R2 = 0.988 and P < 0.001, R2 = 0.983, respectively), indicating that protein and fat growth accelerated after d 69 of gestation. Fetal protein and fat accretions were 0.25 and 0.06 g/d (P < 0.001) before d 69 of gestation, and increased to 4.63 and 1.09 g/d (P < 0.001) after d 69 of gestation. Protein needs for tissue protein gains increased 19-fold after d 69 of gestation. Results of this study indicate that the growth of the fetus and fetal tissues occurs at different rates during gestation and support the practice of a two-phase feeding strategy (before and after approximately d 70 of gestation) for pregnant gilts.  相似文献   

17.
Maternal nutrient restriction leads to alteration in fetal adipose tissue, and offspring from obese mothers have an increased risk of developing obesity. We hypothesized that maternal obesity increases fetal adipogenesis. Multiparous ewes (Columbia/Rambouillet cross 3 to 5 yr of age) carrying twins were assigned to a diet of 100% (Control; CON; n = 4) or 150% (Obese; OB, n = 7) of NRC maintenance requirements from 60 d before conception until necropsy on d 135 of gestation. Maternal and fetal plasma were collected and stored at -80°C for glucose and hormone analyses. Fetal measurements were made at necropsy, and perirenal, pericardial, and subcutaneous adipose tissues were collected from 7 male twin fetuses per group and snap frozen at -80°C. Protein and mRNA expression of fatty acid translocase [cluster of differentiation (CD) 36], fatty acid transport proteins (FATP) 1 and 4, insulin-sensitive glucose transporter (GLUT-4), fatty acid synthase (FASN), and acetyl-coA carboxylase (ACC) was evaluated. Fetal weight was similar, but fetal carcass weight (FCW) was reduced (P < 0.05) in OB versus CON fetuses. Pericardial and perirenal adipose tissue weights were increased (P < 0.05) as a percentage of FCW in OB versus CON fetuses, as was subcutaneous fat thickness (P < 0.001). Average adipocyte diameter was greater (P < 0.01) in the perirenal fat and the pericardial fat (P = 0.06) in OB fetuses compared with CON fetuses. Maternal plasma showed no difference (P > 0.05) in glucose or other hormones, fetal plasma glucose was similar (P = 0.42), and cortisol, IGF-1, and thyroxine were reduced (P ≤ 0.05) in OB fetuses compared with CON fetuses. Protein and mRNA expression of CD 36, FATP 1 and 4, and GLUT-4 were increased (P ≤ 0.05) in all fetal adipose depots in OB versus CON fetuses. The mRNA expression of FASN and ACC was increased (P < 0.05) in OB vs. CON fetuses in all 3 fetal adipose tissue depots. Fatty acid concentrations were increased (P = 0.01) in the perirenal depot of OB versus CON fetuses, and specific fatty acid concentrations were altered (P < 0.05) in subcutaneous and pericardial adipose tissue because of maternal obesity. In conclusion, maternal obesity was associated with increased fetal adiposity, increased fatty acid and glucose transporters, and increased expression of enzymes mediating fatty acid biosynthesis in adipose depots. These alterations, if maintained into the postnatal period, could predispose the offspring to later obesity and metabolic disease.  相似文献   

18.
This study characterized the peripheral plasma placental lactogen (bPL) profile throughout gestation and examined the relationship between the stage of gestation, fetal mass, number, and postpartum lactation with circulating levels of bPL in Holstein cows after nonsurgical embryo transfer. Cows (n = 12) were divided into two groups: Group 1 = single embryo recipient cows (n = 5); Group 2 = twin embryo recipient cows (n = 7). Blood was collected about every third day from Day 0 (Day 0 was defined as the first day of standing estrus), then daily for the last 10 d of gestation, and sampling was stopped 1 d postpartum. The cows were milked twice daily at 0800 and 1800 hr. Two twin-embryo recipient cows had abnormal pregnancies; therefore, their data were excluded from that of the group and reported separately. The time trend concentrations of plasma bPL were significantly affected by the stage of gestation (P < 0.01) but not fetal number (P < 0.21). In both groups bPL levels remained low during the first two trimesters, then increased rapidly (P < 0.01) to peak concentrations between Days 200 and 220, and stabilized at this elevated level until parturition. Postpartum milk yields were indistinguishable between the singleton and twin-bearing cows. Calf birth weight and postpartum lactation were both correlated (P < 0.01) to peripheral bPL concentration in singleton cows, however, this relationship decreased with a subsequent increase in fetal number. Cows giving birth prematurely to stillborn calves or to a schistosomus reflexus calf exhibited a deviating bPL profile. These results indicate that peripheral bPL levels are positively associated with the stage of gestation but not with fetal number. Otherwise, the peripheral pattern of bPL is a valuable index for predicting feto-placental viability.  相似文献   

19.
Mature pregnant crossbred ewes (n = 90) were used in a randomized complete block design and assigned to 1 of 3 winter-feeding systems differing in primary feed source: haylage (HL), limit-fed corn (CN), or limit-fed dried distillers grains (DDGS). Effects of these winter-feeding strategies on ewe and lamb performance were determined. Diets were formulated to meet or exceed NRC (1985) nutrient requirements during gestation and were fed from about d 60 of gestation until parturition. All ewes were fed a common diet postpartum. Every 2 wk during gestation, BW and BCS were collected and diets were adjusted to maintain similar BW gain for ewes fed CN and DDGS vs. HL. At 80 and 122 d of gestation, jugular blood samples were collected at 0, 3, 6, and 9 h postfeeding to measure plasma glucose, insulin, NEFA, and blood urea nitrogen concentrations. At birth, 6 lambs per treatment were killed to measure body composition. At 28 ± 2 d postpartum, milk yield was measured. Lambs were weaned at 61 ± 4 d of age. During mid gestation (d 60 to 115), BW gain of ewes was similar among treatments; however, at d 115 of gestation ewes fed HL had a smaller (P = 0.04) BCS than ewes fed DDGS or CN. Plasma glucose concentrations were greater (P ≤ 0.004) in ewes fed CN than in those fed HL or DDGS just before feeding on d 80 and 122 of gestation, whereas ewes fed DDGS vs. CN or HL had greater (P ≤ 0.04) plasma insulin concentrations at 3 h postfeeding. At parturition, ewe BW was greatest for DDGS, least for HL, and intermediate for CN (P ≤ 0.003). Ewes fed CN and DDGS had greater BCS at parturition than those fed HL, but by weaning, ewes fed DDGS had greater BCS (P ≤ 0.05) than those fed CN or HL. Birth BW tended (P = 0.09) to be heavier for lambs from ewes fed CN and DDGS than from those fed HL prepartum, but there was no difference (P = 0.19) due to ewe gestation diet on lamb BW at weaning. At birth, lamb muscle, bone, organ, and fat measures were not affected (P > 0.13) by treatment. Ewe milk production and lamb preweaning ADG were also similar (P > 0.44) among treatments. Prepartum dam winter feed source did not have detrimental effects on pre- or postpartum ewe performance, but altered prepartum maternal nutrient supply during gestation, which affected birth weight but not preweaning growth or mortality.  相似文献   

20.
Fetal intrauterine position relative to the sex of adjacent fetuses has an effect on reproductive performance in rodents. An experiment was conducted to determine whether sex of adjacent fetuses in utero has an influence on fetal and placental weights and whether the hormonal mechanisms documented in rodents are similar in fetal pigs. Sows were slaughtered at 70.1 +/- 1.7 d (n = 123) and 104.5 +/- .05 d (n = 135) of gestation. The fetuses and placentas were removed from the uterus and the position and sex of each fetus was recorded to indicate whether the fetus was between two males, two females, or a male and a female. Fetal blood was sampled for later hormonal analysis. At 70 d of gestation, male fetal and placental weights were heavier than those of females (P less than .05), but no differences were detected relative to the sex of adjacent fetuses. At 104 d of gestation, a fetus surrounded on each side in utero by fetuses of the opposite sex (two males or two females) was lighter in weight than a fetus surrounded by fetuses of the same sex (P less than .01). Differences in fetal weight due to the sex of adjacent fetuses were not related to placental function because placental weights were generally not different at 104 d of gestation. By 104 d of gestation, most placentas were not separated by necrotic regions and were in close apposition with surrounding placentas. No differences in growth or development could be related to hormonal effects (testosterone, estrone, or estrone sulfate) from surrounding fetuses.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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