IGF-I and NEFA concentrations in fetal fluids of term pregnancy dogs

Insulin-like growth factor-I (IGF-I) and non-esterified fatty acids (NEFA) play an essential role in fetal growth and development. To date, fetal fluids IGF-I and NEFA levels at term canine pregnancy are unknown and could be related to the neonatal development and breed size. For these reasons, the aims of the present study were as follows: (1) to evaluate IGF-I and NEFA concentrations in fetal fluids collected from normally developed and viable newborn puppies born at term of normal pregnancies; (2) to assess possible differences between IGF-I and NEFA levels in amniotic compared with allantoic fluid; (3) to detect possible relationship between breed body size and IGF-I and NEFA amniotic and allantoic concentrations; (4) to evaluate possible differences in IGF-I fetal fluids levels between male and female puppies; and (5) to assess possible correlations between the two hormones in each type of fluid. The study enrolled 25 pure breed bitches submitted to elective Cesarean section at term because of the high risk of dystocia or previous troubles at parturition. At surgery, amniotic and allantoic fluids were collected and assayed for IGF-I and NEFA. IGF-I and NEFA amounts in both amniotic and allantoic fluids of different breed size bitches (small: ≤10 kg; medium: 11–25 kg; large: 26–40 kg) were detected, as well as the effect of gender on IGF-I levels. On a total of 73 amniotic and 76 allantoic samples collected by normal, viable, and mature newborns, the mean IGF-I concentration was significantly higher in amniotic than in allantoic fluid in all three groups, but the amniotic IGF-I levels were significantly lower in small and medium size bitches when compared with large ones. No significant differences were found in allantoic IGF-I concentrations among size groups. A significant effect of the puppy gender on IGF-I content in both fetal fluids was not reported. Regarding NEFA, in all the three groups, the mean NEFA concentration did not significantly differ between amnion and allantois, but in both fetal fluids, higher NEFA levels were detected in samples belonging to small breeds when compared with medium and large. These data strongly indicated that, also in the dog, a relation between fetal fluids IGF-I and NEFA concentrations and breed size exists. Further research is needed to elucidate the possible role of IGF-I and NEFA in the pathologic conditions related to canine fetal growth.     

Bovine amniotic and allantoic fluids for the culture of murine embryos

This study evaluated bovine amniotic and allantoic fluids as culture media for two-cell murine embryos to the hatched blastocyst stage. Amniotic and allantoic fluids were collected from four 70-d periods of pregnancy and pooled from at least five different animals. In Experiment 1 (n = 470) the fluids were frozen twice. Treatments consisted of twice frozen amniotic or allantoic fluid from each pregnancy period, Whitten's medium and fetal calf serum. The later two media were controls. Twice-frozen amniotic fluid <70 d pregnancy period, fetal calf serum and Whitten's medium supported the development of embryos to the hatched blastocyst stage. Whitten's medium was superior to twice-frozen amniotic fluid <70 d pregnancy period or fetal calf serum (P<0.01). Biochemical analysis showed lower glucose in amniotic and allantoic fluids than in Whitten's medium. Experiment 2 (n = 425) was performed to evaluate the effect of glucose supplementation to amniotic fluid. No benefit of glucose supplementation of the amniotic fluid was observed. In Experiment 3 (n = 432), the fluids were transported nonfrozen on ice. Treatments consisted of nonfrozen amniotic fluid <70 d pregnancy period; nonfrozen amniotic fluid <70 d pregnancy period + glucose), nonfrozen allantoic fluid <70 d pregnancy period; and Whitten's medium. The percentages of embryos developing to hatched blastocyst stage were 66.6, 56.5, 57.4 and 63.9% respectively, for each of the four treatments. No differences were found between any two treatments (P<0.05). In Experiment 4 (n = 231) the fluids were stored at -20 degrees C for 15 d. Whitten's medium was superior to amniotic or allantoic fluid <70 d pregnancy period in sustaining embryo development (P<0.05). In conclusion, these data indicate that nonfrozen bovine amniotic or allantoic fluid <70 d pregnancy period can support the development of murine embryos to the hatched blastocyst stage comparable to culture in Whitten's medium. Glucose supplementation of the amniotic fluid offered no advantage, and freezing of fluids had an adverse effect on in vitro embryo development.     

Concentrations of altrenogest in plasma of mares and foals and in allantoic and amniotic fluid at parturition

Treatment with the progestin altrenogest is widely used in pregnant mares. The fact that foals born from healthy mares treated with altrenogest until term suffered from neonatal problems raises the question of direct effects of altrenogest on vital functions in the neonate. We have therefore investigated altrenogest concentrations in maternal and neonatal blood plasma and in fetal fluids. Pregnant mares were treated with altrenogest orally once daily (0,088 mg/kg bodyweight, n = 7) or left untreated (n = 8) from 280 d of gestation until foaling. Altrenogest concentration was determined in plasma of the mares, their foals and in amniotic and allantoic fluid. The concentration of altrenogest in plasma from treated mares (2.6 ± 1.0 ng/mL) was significantly lower than in plasma from their foals immediately after birth (5.6 ± 1.9 ng/mL; p < 0.05), but was significantly higher than in their fetal fluids (amniotic fluid: 0.4 ± 0.1 ng/mL; p < 0.05; allantoic fluid: 3.0 ± 1.5 ng/mL). Altrenogest was undetectable in maternal and fetal plasma and fetal fluids of control pregnancies at all times. Altrenogest concentration in plasma of foals from treated mares was strongly correlated to the altrenogest concentration in plasma of their dams (r = 0.938, p < 0.001) and in amniotic (r = 0.886, p < 0.001) and allantoic fluid (r = 0.562, p < 0.05). A significant decrease in altrenogest concentration between the time periods 0-15 min, 30-120 min, and 180-360 min after parturition was seen in the plasma from foals born to altrenogest-treated mares. In conclusion, our data demonstrate that altrenogest reaches the equine fetus at high concentrations.     

Presence of the major progesterone-induced proteins of the sheep endometrium in fetal fluids

Allantoic and amniotic fluids were collected on Days 60 (n = 3), 100 (n = 4), and 140 (n = 3) of pregnancy. The presence of uterine milk proteins (UTM-proteins) in these samples was evaluated by Ouchterlony immunodiffusion and enzyme-linked immunoabsorbant assay (ELISA). Eight of ten samples of allantoic fluid and three of ten samples of amniotic fluid produced one or two immunoprecipitin bands against antiserum to UTM-proteins. Each band fused with immunoprecipitin bands from UTM-proteins purified from uterine fluid. Data from a semi-quantitative ELISA indicated that allantoic fluid from all ewes and amniotic fluid from six of ten ewes contained immunoreactive UTM-proteins. Concentrations of UTM-proteins in these fluids were not statistically affected by day of gestation (p greater than 0.10), but tended to decline as gestation advanced. Greater concentrations of UTM-proteins were detected in allantoic fluid than in amniotic fluid (p less than 0.05). The physical characteristics of the immunoreactive material in allantoic and amniotic fluids were examined by polyacrylamide gel electrophoresis and Western blotting. The immunoreactive material was found to possess pIs and molecular weights identical to UTM-proteins. These results indicate that fetal fluids contain material that reacts with antiserum to UTM-proteins and has physical properties similar to UTM-proteins. It is likely, therefore, that the UTM-proteins are transported across the placenta during gestation, perhaps to serve some function in the fetal compartment.     

Concentrations and antioxidative activity of anserine and carnosine in poultry meat extracts treated with demineralization and papain

Anserine and carnosine found in animal skeletal muscle are capable of inhibiting the catalysis of lipid oxidation by heme and non-heme iron. A demineralization technique and a proteolytic enzyme (papain) were used in this research in order to reduce the levels of proxidants while maintaining high levels of anserine and camosine in poultry (chicken, duck and turkey) meat extracts. Undemineralized poultry meat extracts contained larger amounts of anserine, camosine, heme and non-heme iron (p < 0.05) than did demineralized poultry meat extracts. Both undemineralized and demineralized breast meat extracts of chicken, duck and turkey contained higher concentrations of anserine and camosine, but lower amounts of heme and non-heme iron than did thigh meat extracts. In chicken, duck and turkey meat (breast and thigh) extracts (undemineralized and demineralized), the anserine concentrations were greater (p < 0.05) than the camosine concentrations. The hydrogen-donating ability of undemineralized and demineralized chicken breast meat extracts was not significantly different (p > 0.05): however, demineralized chicken breast meat extracts showed higher (p < 0.05) ferrous chelating ability than did undemineralized meat extracts. The concentrations of anserine, camosine, heme and non-heme iron in chicken breast meat extracts increased (p < 0.05) with the addition of papain (1%) to the meat mixture before extraction. Heme and non-heme iron in the chicken breast meat extracts increased as the reaction time for papain increased from 30 to 120 min, but the concentrations of anserine and camosine were not significantly affected by the longer reaction time for papain. The hydrogen-donating ability and ferrous chelating ability of demineralized chicken breast meat extracts were not significantly affected by papain. The ratios of carnosine/anserine were very specific in the chicken, duck and turkey meat extracts (breast and thigh); and the turkey meat extracts had lower (p < 0.05) camosine/anserine ratios than did the chicken and duck meat extracts. The camosine/anserine ratios of undemineralized and demineralized poultry meat extracts were not significantly different (p > 0.05). This suggests that the carnosine/anserine ratios of undemineralized chicken (0.62 - 0.80), duck (0.75 - 0.77) and turkey (0.15 - 0.16) meat extracts could be used to estimate the single meat species in uncooked or cooked meat products.     

Suppression of lymphocyte reactivity in vitro by porcine allantoic and amniotic fluids

Porcine allantoic and amniotic fluids from early, mid and late pregnancy were analyzed for protein constituents and ability to suppress phytohemagglutinin (PHA)-induced lymphocyte transformation. All fetal fluids contained alpha-fetoprotein as evaluated by polyacrylamide gel electrophoresis (PAGE), with the highest concentrations appearing in mid-pregnancy amniotic fluids. In addition, allantoic fluids from mid-pregnancy contained proteins assumed to be secreted by the uterus. Both allantoic and amniotic fluids from mid-pregnancy were suppressive to PHA-induced lymphocyte transformation (P<.01). Thus it was concluded that substances, potentially able to suppress the immune response locally, exist within porcine fetal fluids, but it was not determined whether this material is of solely fetal or maternal origin, or a combination.     

The IGF-system in healthy pre- and postmenopausal women: relations to demographic variables and sex-steroids

Plasma insulin-like growth factor (IGF)-I, free IGF-I and -II, IGF-binding protein (IGFBP)-1, -2, and -3 together with IGFBP-3 protease activity were measured in 114 postmenopausal and 39 premenopausal healthy women. For each parameter, the mathematical distribution was characterised, and the normal range for pre- and postmenopausal women described, together with correlations to demographic variables and sex-steroids (postmenopausal women).Postmenopausal women had lower levels of plasma IGF-I (P<0.001) and free IGF-I (P<0.001) compared to premenopausal women, while plasma IGFBP-2 (P<0.05) and immunoreactive IGFBP-3 (P<0.001) were higher in postmenopausal women. Free IGF-I (but none of the other parameters) was significantly lower in postmenopausal smokers compared to non-smokers (P<0.05).IGF-I and -II both correlated positively to height (r=0.203, P<0.05 and r=0.198, P<0.05, respectively), while IGF-II correlated positively to weight (r=0.250, P<0.01). Plasma IGF-I correlated positively to androstenedione (r=0.292, P<0.01) and dehydroepiandrosterone sulphate (DHEAS, r=0.202, P<0.05), while a significant positive correlation was observed between IGF-II on the one side and oestradiol (E(2), r=0.227), oestrone sulphate (E(1)S, r=0.238) and androstenedione (r=0.213) on the other side (P<0.05 for all).Our results support a relation between sex-steroids and IGF-I and -II in healthy postmenopausal women. The lower levels of total and free IGF-I in postmenopausal compared to premenopausal women indicate lower bioavailability of this growth factor in elderly females.     

Conjugated and unconjugated oestrogens in fetal and maternal fluids of the cow throughout pregnancy.

The changes in concentration of oestrone, oestradiol (-17alpha and -17beta), oestrone sulphate and the oestradiol sulphates have been measured in allantoic and amniotic fluids and in maternal peripheral plasma throughout gestation. Oestrone sulphate was the major oestrone present in all of the fluids. It was measurable in allantoic fluid before Day 52 and reached a peak concentration of 475 ng/ml around Day 133. A lower peak occurred in the amniotic fluid around Day 110. The changes in oestradiol sulphates in allantoic fluid were similar to those of oestrone sulphate but at a much lower level. Considerable fluctuation was observed in the oestradiol sulphate concentrations in amniotic fluid. The ratio of oestradiol-17alpha sulphate to oestradiol-17beta sulphate was considerably higher in amniotic fluid than in allantoic fluid. Consistent changes in the levels of oestrone and the oestradiols were found in amniotic fluid but not in allantoic fluid during the second half of pregnancy. In maternal peripheral plasma oestrone sulphate was measurable before Day 72. In the limited number of samples analysed no difference in oestrogen concentration due to the sex of the fetus was evident in any of the fetal or maternal fluids.     

The insulin-like growth factor system and markers of inflammation in adult patients with inflammatory bowel disease

BACKGROUND AND OBJECTIVES: Catabolism and growth impairment are well-known complications of inflammatory bowel disease (IBD). Recent studies have demonstrated significant changes in the IGF system in IBD patients. The aim of the present study was to investigate correlations between the IGF system and markers of inflammation in IBD. METHODS: A cross-sectional study comprising 99 IBD patients (Crohn's disease (CD, n = 50) and ulcerative colitis (UC, n = 49)). Correlations between markers of inflammation and IGF-I, IGF-II and IGFBP-3 were examined in CD and UC patients in remission and relapse. The patients were clinically scored using Crohn's Disease Activity Index (CDAI) for CD patients and Activity Index (AI) for UC patients. RESULTS: In the UC group we found correlations between IGF-I and CRP (r(s) = Spearman's rho) (r(s) = -0.40, p < 0.01) and albumin (r(s) = 0.46, p < 0.001), IGFBP-3 and albumin (r(s) = 0.36, p < 0.01) and AI score (r(s) = -0.31, p < 0.05). IGF-II correlated with CRP (r(s) = -0.42, p < 0.01), IL-6 (r(s) = -0.65, p < 0.001), albumin (r(s) = 0.41, p < 0.01), AI score (r(s) = -0.30, p < 0.05) and orosomucoid (r(s) = -0.47, p < 0.001). In the CD group we found correlations between IGF-I and CRP (r(s) = -0.40, p < 0.05), and albumin (r(s) = -0.46, p < 0.01), IGFBP-3 and albumin (r = 0.36, p < 0.01). IGF-II correlated with IL-6 (r(s) = -0.65, p < 0.001), albumin (r(s) = 0.41, p < 0.01), CDAI score (r(s) = -0.30, p < 0.05) and orosomucoid (r(s) = -0.47, p < 0.001). CONCLUSIONS: IGF-I, IGF-II and IGFBP-3 are correlated to albumin and IGF-I and IGF-II are correlated to CRP in IBD patients. Further, IGF-II is correlated to IL-6 in IBD patients. This may suggest a correlation between inflammation and the IGF system with involvement in muscle and bone catabolism in IBD.     

Influence of IGF-I on buffalo (Bubalus bubalis) spermatozoa motility, membrane integrity, lipid peroxidation and fructose uptake in vitro

The objective of the present experiment was to examine the influence of mean physiological concentration of insulin-like growth factor-I (IGF-I) on frozen-thawed Surti buffalo (Bubalus bubalis) spermatozoa functional parameters, i.e., motility, plasmalemma integrity, acrosomal integrity, functional membrane integrity, lipid peroxidation and fructose uptake in vitro. Frozen-thawed semen samples (n=6) were washed in tris buffer and divided into two equal parts (control and IGF-I groups). Only in the IGF-I group, IGF-I (rhIGF-I analogue) was added to a final concentration of 100 ng/ml. The samples were incubated at 37 degrees C for 2h and the assessments were made at 0, 30, 60, 90 and 120 min of incubation. The mean concentration of the buffalo seminal plasma (n=17) IGF-I was 116.83+/-28.34 ng/ml (range 41.4-198.95). IGF-I had significant effect on the total motility (P<0.01), progressive forward motility (P<0.01), functional membrane integrity (P<0.05) and lipid peroxidation levels (P<0.05) during the 120-min study period as assessed by area under curve. Treatment with IGF-I increased (P<0.01) the total spermatozoa motility at 30, 60 and 90 min as compared to the control. The progressive forward motility was significantly (P<0.01) higher at 60 and 90 min of incubation. The addition of IGF-I resulted in significant (P<0.01) increase in straight-line velocity (VSL, microm/s) as compared to the control at 60 and 90 min of incubation. The linearity (%) was significantly (P<0.01) higher in IGF-I treated semen as compared to control at 60 min of incubation. Plasmalemma integrity in IGF-I group was significantly (P<0.05) higher than control at 30 and 60 min of incubation. The functional membrane integrity differed significantly (P<0.01) between groups (control and IGF-I) at 60 and 90 min of incubation. The percentage of acrosomal intact spermatozoa decreased continuously over a period of time in both the groups. As compared to 0 min of incubation, the significant (P<0.05) loss of acrosome was observed at 60 and 90 min of incubation in control (63.87+/-3.17 vs. 58.52+/-2.54) and IGF-I (61.60+/-2.26 vs. 56.11+/-2.12) groups, respectively. Lipid peroxidation levels were significantly lower in IGF-I group at 90 min (P<0.05) and 120 min (P<0.01) of incubation than the control group. Fructose utilization was significantly higher in IGF-I group as compared to control at 30 min (P<0.05) and 60 min (P<0.01) of incubation. The present study suggests that addition of IGF-I improve spermatozoa functional parameters by reducing lipid peroxidation levels.     

Soluble fetoproteins in chorioallantoic membrane from chick embryo (Gallus domesticus).

1. Anti-chorioallantoic membrane (CAM) serum was made fetal-specific by absorbing it in a mixture of egg white, fresh yolk and chicken serum, plus liver, lung, heart and spleen from a laying hen. 2. By immunoelectrophoresis, the CAM extract shows three soluble transitory proteins, an oncofetal protein (alpha-fetoprotein) and a soluble organ permanent protein from some of the organs used in the absorption. 3. By assaying crossed heterologous systems, alpha fetoprotein was found in the allantoic, amniotic and yolk fluids after 14 days of incubation; all three proteins were found in amniotic, but neither in allantoic nor in yolk fluid.     

Studies on enzymes of nitrogen metabolism, and nitrogen end products in the developing chick (Gallus domesticus) embryo.

1. A total of 450 fertilized eggs were used to study the concentrations of uric acid, urea and ammonia in allantoic and amniotic fluids, and some enzymes of nitrogen metabolism in the liver and kidney during the development of the chick embryo from the 5th to 21st day of incubation. 2. Concentrations of the compounds studied were higher in allantoic fluid. The molar concentration of allantoic uric acid increased steadily with time. The pattern of urea and ammonia in both allantoic and amniotic fluids were the same. 3. Arginase (E.C.3.5.3.1) activity in both embryonic kidney and definitive kidney was higher than that in the liver. The specific activity of arginase (mumole urea formed/hr per g wet wt kidney) dropped during development. 4. Little arginine synthetase activity (argininosuccinate synthetase, E.C.6.3.4.5; and argininosuccinate lyase, E.C.4.3.2.1) was found in kidney, but none in the liver. 5. The complete urea cycle function was absent in both the liver and the kidney of the chick embryo.     

Pregnancy-specific protein B (PSPB), progesterone and some biochemical attributes concentrations in the fetal fluids and serum and its relationship with fetal and placental characteristics of Iraqi riverine buffalo (Bubalus bubalis)

This study was carried out to demonstrate the pregnancy-specific protein B (PSPB), progesterone and some biochemical parameters concentrations in amniotic fluid, allantoic fluid and fetal serum collected from slaughtered Iraqi riverine pregnant buffaloes at three different months of gestation (6th, 7th and 8th). Ten out of 22 adult buffaloes of 4.6 ± 0.97 years old were used in this study. The buffaloes were mated naturally by monitoring the estrus cycles via appearance of vaginal fluids and mounting by bulls. Pregnancy was checked for these buffaloes by non-returning to estrus for three estrus cycles and assured by rectal palpation on day 61 post-mating (PM). Buffaloes were slaughtered at three different periods of gestation (three at 6th month, four at 7th month and three at 8th month of gestation) to verify the progesterone and PSPB as well as some blood attributes levels (glucose, cholesterol, total protein, albumin, globulins and albumin: globulins ratio) in amniotic fluid (AF), allantoic fluid (LF) and fetal serum (FS). Progesterone was higher (P<0.01) in LF at the 8th month of gestation and lower in FS during the 7th and 8th months of pregnancy. PSPB concentrations were greater in FS (6th and 8th months in particular) than in both AF and LF. The overall mean of cholesterol concentration was higher in FS (P<0.05) followed by AF and LF that had the lowest concentration. The FS exhibited higher total protein during the three gestation periods. Most of fetal and placental measurements increased as the pregnancy advanced. In conclusion, these results described, for the first time, the PSPB and progesterone concentrations and blood characteristics in fetal fluids and serum in water riverine buffaloes during different stages of pregnancy. Progesterone concentrations were greater in allantoic fluid than in other fluids. In contrast, PSPB and other blood attributes were higher in fetal serum than other fluids of Iraqi riverine buffaloes. These findings reflect the changes in hormones, proteins and other metabolites during different gestation periods.     

Decline in lung liquid volume and secretion rate during oligohydramnios in fetal sheep

Reduced amniotic fluid volume often results in fetal lung hypoplasia. Our aim was to examine the effects of prolonged drainage of amniotic and allantoic fluids on lung liquid volume (Vl), secretion rate (Vs), and tracheal flow rate (Vtr) in fetal sheep. In five experimental animals, amniotic and allantoic fluids were drained from 107 to 135 days of gestation. The volume of fluid drained from the experimental animals was 411.8 +/- 24.4 ml/day (n = 140). In six control animals, amniotic fluid volume was 747.7 +/- 89.7 ml (n = 15). Wet and dry lung weights were 20-25% lower in experimental fetuses than in control fetuses. Fetal hemoglobin, O2 saturation, arterial PO2, pH, and hematocrit were unchanged by drainage. During the drainage period, Vl was up to 65% lower, Vs was up to 35% lower, and Vtr was up to 40% lower in experimental fetuses than in control fetuses. We conclude that prolonged drainage of amniotic and allantoic fluids decreases Vl, Vs, and Vtr in fetal sheep. These findings indicate that fetal lung hypoplasia associated with oligohydramnios may be the result of a prolonged reduction in Vl.     

A role for LH in the regulation of expression of mRNAs encoding components of the insulin-like growth factor (IGF) system in the ovine corpus luteum

Evidence suggests the insulin-like growth factor (IGF) system may be involved in luteal maintenance and regression. However, previous studies have only investigated a few components of the system, primarily in bovine and non-ruminant species. The present study investigated gene expression for the components of the IGF system in ovine corpora lutea (CL) at various key stages of the oestrous cycle (Experiment 1), and the possible regulatory effects of LH on IGF gene expression in ovine CL using a GnRH antagonist model system (Experiment 2). Experiment 1 revealed that IGF-I (P<0.001), type I (P=0.008) and II (P=0.005) IGF-Rs and IGFBP-5 (P<0.05) mRNA levels were significantly elevated in early regressing CL. In contrast, IGF-II levels were high in CL but did not vary throughout the oestrous cycle, while IGFBP-2, -3, -4 and -6 mRNA levels were highest throughout the luteal phase but lower in regressing CL (P<0.05). IGFBP-1 mRNA could not be detected in any CL. Abrogation of LH action following GnRH antagonist administration (Experiment 2) resulted in a significant increase in expression for IGF-I (P<0.001), type II IGF-R (P=0.004) and IGFBP-5 (P<0.05) after only 12h, but these increases were transient. IGF-II, type I IGF-R and IGFBP-2, -3, -4 and -6 mRNA levels remained unaffected by GnRH antagonist treatment. These data highlight the role that LH plays in regulating IGF-I gene expression and lends further support that IGF-I may be a key luteotrophic factor in sheep.     

Ultrasonographic evaluation of the equine placenta by transrectal and transabdominal approach in the normal pregnant mare

The objective of this study was to determine normal variations in the utero placental thickness during mid- and late gestation in the mare. Normal, healthy pregnant mares (n = 9) were examined monthly from 4 mo of gestation until parturition by transrectal and transabdominal ultrasonography. At each examination, the combined thickness of the uterus and the placenta (CTUP) was measured at the placento-cervical junction (transrectally) and at the uterine body or the uterine horns (transabdominally). In addition, the echogenicity of the amniotic and allantoic fluids was evaluated by transrectal ultrasonography. Following parturition and expulsion of the fetal membranes, the allantochorion was measured and visually examined for abnormalities. At all examinations, both transrectal and transabdominal, the chorioallantois and the uterus were indistinguishable from each other on the ultrasound image. The CTUP, measured by transrectal ultrasonography did not change between 4 and 8 mo of gestation, but increased significantly for each month between 10 and 12 mo of gestation (P < 0.001). A change in the CTUP was detected between months when measured by transabdominal ultrasonography, but no distinct pattern in these changes was observed. No correlation was found between transabdominal and transrectal measurements of the CTUP. The echogenicity of the amniotic and allantoic fluids did not consistently change over time during mid- and late gestation. The amniotic fluid was more echogenic than the allantoic fluid at most examinations from 6 mo of pregnancy and throughout gestation (P < 0.05). It was concluded that transrectal ultrasonographic examination to assess the CTUP and the echogenicity of the fetal fluids is superior to the transabdominal approach. We suggest that transrectal ultrasonographic examination should be added to current diagnostic tools during late gestation and that it be part of the biophysical profile of high risk equine pregnancies.     

Proteins in the amniotic and allantoic fluids of fetal pigs

Seven proteins were identified in the amniotic and allantoic fluids of fetal pigs (Sus scrofa domesticus) using crossed immunoelectrophoresis: albumin, fetuin, transferrin, alpha-fetoprotein (AFP), alpha 1-acid glycoprotein, alpha 1-antitrypsin and alpha 2-macroglobulin. The total protein concentrations were determined by the method of Bradford and individual protein concentrations by radial immunodiffusion or rocket immunoelectrophoresis. Transferrin and fetuin were the major proteins in amniotic fluid during the second trimester of gestation and together with AFP and albumin accounted for the majority of the total protein in amniotic, but not allantoic fluid.     

The influence of gestational age and onset of labour on determinants of fetal-maternal fluid and electrolyte balance in sheep.

Our aim was to compare the effects of gestational age and the timing of the onset of labour on factors influencing fetal fluid and electrolyte balance and urine production in fetal sheep. We measured the volume and composition of fetal urine and amniotic and allantoic fluids, as well as fetal and maternal plasma composition and micturition episodes in sheep during late gestation until the onset of labour. We found that daily fetal urine production and urethral urine flow per micturition episode increased significantly in relation to the onset of labour but not to gestational age (P < 0.05). In the 2 days preceding the onset of labour fetal urine and amniotic fluid K+ concentrations and urine osmolality increased significantly and the Na+/K+ ratio in allantoic fluid decreased significantly (P < 0.05). There was also a significant fall in fetal arterial SaO2 (P < 0.05) but no significant changes occurred in fetal plasma electrolyte composition, osmolality or AVP concentrations. Fetal plasma cortisol and prolactin concentrations and amniotic and allantoic fluid prolactin concentrations increased significantly and progressively in association with both advancing gestation and the onset of labour whereas maternal plasma prolactin concentrations increased significantly only in the 2 days before the onset of labour (P < 0.05). We conclude that some developmental aspects of fetal fluid and electrolyte balance, including renal function, are more closely related to the timing of parturition than to gestational age per se.     

Hormonal and physical changes associated with bovine conceptus development.

Conceptus (placental membranes, fetal fluids and fetus) development was characterized between Days 27 and 111 of gestation. Progestagens, oestrone, oestradiol, oestrone sulphate and prostaglandins (PG) F were measured in maternal plasma and allantoic and amniotic fluids. Protein concentrations are described for fetal fluids. The early increase in placental membrane weight from 1.12 g (27 days) to 58.45 g (50 days) was associated with oestrogen production presumably of conceptus origin. Oestrogens increased significantly in allantoic and amniotic fluids throughout the period studied with oestrone being the primary free oestrogen, rising from 2 pg/ml (Day 33) to 144 ng/ml by 111 days in allantoic fluid. Changes in plasma oestrogens of the maternal circulation were not detected until after Day 70 at which time oestrone concentration was greater than that of oestradiol. Fetal fluid concentrations of progestagens, oestrone sulphate and PGF were not related to maternal plasma levels and a sequestration of these hormones by the allantois is postulated.