scholarly journals Maternal undernutrition during mid-pregnancy in sheep. Placental size and its relationship to calcium transfer during late pregnancy

1991 ◽  
Vol 65 (2) ◽  
pp. 157-168 ◽  
Author(s):  
G. J. Mccrabb ◽  
A. R. Egan ◽  
B. J. Hosking

The aim of the present experiment was to determine the relationship between placental and fetal weight after placental growth had been retarded by maternal undernutrition. Placental weight and fetal weight were measured in single-lamb-bearing ewes which were well-fed throughout pregnancy, or severely undernourished between the 30th and 96th day of pregnancy. Placental transfer of calcium and whole-body metabolism of both glucose and Ca were measured during late pregnancy. The change in fleece-adjusted live weight between the 30th and 96th day of pregnancy was 99 (se 9.8) and – 146 (se 9.6) g/d for the well-fed and undernourished ewes respectively. The condition score of well-fed ewes did not significantly change between the 96th (2.9 (se 0.08)) and 140th (3.0 (se 0.13)) day of pregnancy, while it increased from 1.6 (se 0.15) to 2.3 (se 0.11) for the previously undernourished group. Undernutrition caused an increase (P < 0.01) in placental weight measured on the 96th (21%) and 140th (30%) day of pregnancy. In contrast fetal growth was not significantly affected by maternal undernutrition. While the voluntary dry matter intakes (g/d) of previously undernourished ewes after the 97th day of pregnancy were higher than for their well-fed counterparts, there was no significant difference between whole-body glucose or Ca metabolism, or the placental transfer of Ca measured during late pregnancy. This experiment confirms earlier reports of an increase in placental weight as a result of maternal undernutrition during mid-pregnancy; but the factors causing and the functional significance of this response have not been identified. Contrary to earlier proposals, placental weight per se did not limit fetal growth during late pregnancy. It is hypothesized that a combination of factors originating from maternal, placental and fetal sources act together to regulate growth of the fetus.

1990 ◽  
Vol 64 (2) ◽  
pp. 449-462 ◽  
Author(s):  
B. J. Leury ◽  
A. R. Bird ◽  
K. D. Chandler ◽  
A. W. Bell

Maternal whole-body glucose entry rate and uterine and umbilical net uptakes of glucose and oxygen were measured in single-pregnant ewes which were either well-fed throughout, or fed at 0.3–0.4 predicted energy requirement for 7–21 d during late pregnancy. All ewes were studied while standing at rest and then while walking on a treadmill at 0.7 m/s on a 10° slope for 60 min. Underfed ewes suffered significant decreases in live weight and had lower fetal, but not placental, weights at 140–144 d gestation. Undernutrition also caused large decreases in maternal glycaemia and glucose entry rate, which were associated with equally large decreases in uterine and umbilical net uptakes and O2 quotients of glucose, and with a decrease in placental glucose transfer capacity. Exercise caused increases in maternal blood concentration, entry rate and uterine net uptake of glucose, the magnitudes of which were not significantly affected by plane of nutrition. Umbilical glucose uptake and placental glucose transfer capacity increased during exercise in underfed but not fed ewes. The fractional distribution of maternal glucose to the pregnant uterus, and of uterine glucose uptake to the fetus, were unaltered by undernutrition; during exercise, a disproportionately small fraction of the increased maternal glucose supply went to the uterus. The results confirm that the ovine conceptus responds to nutritional reduction in maternal glucose availability in a manner similar to non-uterine maternal tissues. Major reductions in glucose supply appear to override putative glucose-sparing mechanisms which may operate to favour the conceptus in better-nourished animals.


1997 ◽  
Vol 48 (6) ◽  
pp. 743 ◽  
Author(s):  
D. M. McNeill ◽  
R. W. Kelly ◽  
I. H. Williams

The effect of ewe fatness on fetal weight at term was tested without the confounding effects of placental weight and feed intake. We hypothesised that fetal weights should be similar in fat or lean ewes with placentas of a similar size, and tested the hypothesis by manipulating nutrition so that, at mating, Merino ewes carrying a single fetus were in a medium (score 2·9, liveweight 46·6 kg) or lean (score 2·0, liveweight 40·6 kg) condition. They were maintained at this fatness difference until slaughter at Day 146 of pregnancy when fetal, placental, and maternal tissues were weighed and analysed for composition. Subgroups (n = 8 per fatness group) slaughtered at Day 110, a stage when most placental hypertrophy is complete but the majority of fetal hypertrophy is yet to occur, confirmed that the treatments differed in ewe fatness (3·82 v. 9·19 kg empty-body fat, s.e.m. = 0·960; P < 0·001) but not placental weight (487 v. 538 g, s.e.m. = 41·5, P > 0·05). By Day 146, fatness differences (4·77 v. 9·56 kg empty-body fat, s.e.m. = 0·960, P < 0·001) and placental similarities (434 v. 502 g, s.e.m. = 38·3, P > 0·05) were maintained, and both groups produced fetuses of similar size (4408 v. 4382 g, s.e.m. = 204·6, P > 0·05). However, the fetuses in the lean ewes had 20% less fat/kg fat-free body weight (24 v. 30 g/kg, s.e.m. = 1·3, P < 0·01). Fetal weight was correlated with placental weight (r = 0·70; P < 0·01) but not with ewe fatness. Fetal fatness, however, was correlated with ewe fatness (r = 0·69; P < 0·01). Ewe fatness per se did not influence fetal size but did influence the deposition of fat in the fetus, possibly via a greater ability of fatter ewes to partition more glucose toward their fetus.


1968 ◽  
Vol 22 (4) ◽  
pp. 635-643 ◽  
Author(s):  
J. W. Mathers ◽  
R. Hill

1. Groups of pullets were given a diet of high (106–107 μg/g) or low (6–7 μg/g) manganese content and killed either before sexual maturity, at the point-of-lay or after a 6- to 7-month laying period. The birds were dissected into six tissue fractions: skeleton, liver, kidney, ovary and oviduct, skin and feathers, and muscle with remaining tissue. Total Mn and concentration of Mn as μg/g dry fat-free tissue were determined for each fraction.2. There were no differences in live weight attributable to level of dietary Mn, and no differences in egg production.3. Mean total body Mn varied among groups over a fairly narrow range (528–738 μg), with the exception of birds given the high-Mn diet throughout the experiment, in which the mean was 2319 μg. This represented an increase in Mn content during egg laying of 244%. There was no significant difference in the Mn content of birds given the low-Mn diet whether they were killed at the point-of-lay or after the laying period.4. The effects of treatment on the weight of Mn in each of the tissue fractions are described. The very large increase in total Mn that occurred during egg production in birds given the high-Mn diet was accounted for largely by the increase in skin and feathers (1072 μg Mn).5. In general terms, the Mn content of liver, kidney and ovary and oviduct together constituted only just over 10% of total body Mn, the remainder being distributed about equally among skeleton, skin and feathers, and muscle with remaining tissue.6. There was a close parallel between the concentration of Mn of a tissue and the total weight of Mn it contained except in certain instances when stage of maturity or egg production influenced weight of the tissue.7. The effects of treatments on the Mn contents of these birds are discussed in relation to the retention of dietary Mn, and the withdrawal from and accumulation of Mn in individual tissues and the whole body.


2004 ◽  
Vol 16 (9) ◽  
pp. 273
Author(s):  
A. N. Sferruzzi-Perri ◽  
J. A. Owens ◽  
J. S. Robinson ◽  
C. T. Roberts

Insulin-like growth factor (IGF)-II is an important regulator of growth in many tissues and is abundantly expressed in the placenta during pregnancy. Gene ablation studies performed in mice have shown that IGF-II deficiency results in both impaired fetal and placental growth, whereas deficiency in IGF-I reduces fetal growth only. Conversely, maternal IGF supplementation in early pregnancy in the guinea pig increases placental and fetal size by mid pregnancy. This study aimed to determine whether these anabolic effects persist into late pregnancy after cessation of treatment. On Day 20 of pregnancy, mothers were anaesthetised and a mini osmotic pump was implanted subcutaneously, to deliver 1mg/kg/day IGF-I (n = 7), IGF-II (n = 9) or vehicle (n = 7) for 17 days. Guinea pigs were killed on Day 62 of pregnancy (term ~67 days). Fetal and placental weights, and maternal and fetal body composition, were measured. Total litter size was unaffected by IGF treatment; however, IGF-II increased the number of viable fetuses by 26% (P = 0.01). After adjusting for the number of viable pups per litter, maternal IGF treatment increased fetal growth by increasing abdominal circumference, crown-rump length and fetal weight (fetal weight: IGF-I 79+/–2.5 g; IGF-II 78+/–2.6 g; vs vehicle 68+/–2.5 g, P = 0.02). IGF treatment did not alter absolute or relative fetal organ weights. IGF-I reduced placental weight by 9% and IGF-II increased it by 9%, but not significantly. IGF-I increased the fetal weight�:�placental weight ratio (19+/–0.9 vs 15+/–0.9, respectively P = 0.043). IGF treatment did not affect maternal weight gain during pregnancy nor net carcass weight; however, IGF-I reduced maternal lung and adipose tissue weights. In conclusion, maternal IGF-II treatment during early pregnancy improved fetal growth into late gestation, possibly by modulating placental efficiency. As poor placental development is implicated in fetal growth restriction, increasing maternal IGF abundance in early to mid pregnancy may be a potential therapeutic approach to placental insufficiency.


1992 ◽  
Vol 43 (2) ◽  
pp. 315 ◽  
Author(s):  
PJ Holst ◽  
CJ Allan ◽  
AR Gilmour

A moderate below maintenance nutritional restriction was applied to pregnant ewes for 4 weeks commencing at either 79, 87 or 95 days post coitus. Measurements were made after slaughter at the end of each restricted period and at Day 144 of pregnancy on the uterus and fetus of restricted and control ewes. Lambs were weighed at birth. Overall there was no significant difference in the response of ewes to timing of restriction but there was a response to restriction. Dietary restriction reduced fetal growth rate, girth size, crown rump length (CRL) and weight of other fetal tissues. Though reduced, girth size and CRL maintained their normal relationship with fetal weight. Growth rates of fetuses on all treatments were similar during refeeding. The largest effect of nutritional restriction on the reproductive tract occurred in lower fetal membrane weights at 144 days of pregnancy (mean of restricted group 595 g v. 761 g controls). At that time, previously restricted ewes also had an increased number of cotyledons but decreased average weight of cotyledons compared to control ewes. Fetal weight at Day 144 was significantly correlated with girth and CRL (P < 0.01) and placental weight (P < 0.05) but not with weight of fetal membrane or cotyledons. Birth weights of single and twin lambs from the restricted ewes were similar to that of the controls and appeared to be unaffected by the restriction. Small differences in the gestation length of ewes bearing twin lambs may have helped to overcome the deficit in fetal weight observed at Day 144 in ewes bearing single lambs. It was concluded that ewes respond to dietary restriction followed by improved forage availability with changes in maternal and fetal growth patterns that presumably interact to produce viable lambs.


2012 ◽  
Vol 52 (7) ◽  
pp. 533 ◽  
Author(s):  
N. P. Martín ◽  
P. R. Kenyon ◽  
P. C. H. Morel ◽  
S. J. Pain ◽  
C. M. C. Jenkinson ◽  
...  

Maternal nutrition affects fetal development, with potential lifelong consequences. The study reported here compared the anatomical development (dimensions and organs) of twin fetuses at Day 140 of gestation, from 58 twin-bearing ewes fed at one of three different nutritional treatments in early pregnancy [Day 21–50, Low (LD21–50) versus Medium (MD21–50) versus High (HD21–50)] and one of two different nutritional treatments in mid- to late pregnancy (Day 50–140, Medium (MD50–140) versus High (HD50–140)]. There were no effects (P > 0.05) of either early or mid- to late pregnancy nutrition on placental weight and fetal bodyweight or size measurements at Day 140. Semitendinosus muscles from LD21–50-HD50–140 fetuses were heavier (P < 0.05) than those from LD21–50-MD50–140 and HD21–50-HD50–140 fetuses, and fetuses from LD21–50 dams had lighter (P < 0.05) mammary glands compared with those from MD21–50 and HD21–50 dams, even after adjustment for fetal weight. Maternal nutrition also affected (P < 0.05) the weights of the fetal thyroid and brain. These results suggest that farmers can limit ewe nutrition in early pregnancy with only minor effects on the fetus. To investigate potential lifetime effects, a larger cohort of these animals is currently being monitored.


1982 ◽  
Vol 35 (1) ◽  
pp. 81-85 ◽  
Author(s):  
Ruth Henderson ◽  
C. T. Whittemore ◽  
M. Ellis ◽  
W. C. Smith ◽  
R. Laird

ABSTRACTConsistent age differences at around 27 kg live weight have been found between control (C) and selection (S) line boars of the Large White breed in a coordinated breed improvement programme (89·8 v. 94·6 days, P<001). After 10 generations of index selection on feeding ad libitum, a sample of 20 boars from the programme, 10 C and 10 S, were slaughtered at 27·6 (s.e. 0·48) kg live weight for a more comprehensive examination of this finding. Physical dissection of the carcass and whole body chemical analysis were carried out. Differences between C and S boars were apparent even at this light weight: S boars were older than C (92·7 v. 83·5 days, P<0·01), contained less dissected fat (2·93 v. 3·58kg, P<005) and chemical lipid (315 v. 3·59kg, P<0·05), and had a higher lean proportion (0·477 v. 0·458, P<0·01). There was no significant difference between lines in weight of dissected lean or whole body protein. Index selection has clearly affected early growth and body composition, which questions current assumptions underlying pig testing methods.


1983 ◽  
Vol 50 (2) ◽  
pp. 249-265 ◽  
Author(s):  
G. D. Baird ◽  
J. G. Van Der Walt ◽  
E. N. Bergman

1. Constant infusions of D-[U-14C]glucose, D-[6−3H]glucose and L-[U-14C]lactate were used to determine rates of apparent turnover, de novo production, disposal and interconversions of glucose and lactate, together with total recycling of glucose-C, in ewes and dairy cows during late pregnancy and early lactation. The cows were also examined while being fasted. In the fed animals, infusions were made within 5 h after the morning meal when steady-state conditions appeared to exist.2. In the ewes, circulating concentrations of glucose and lactate, and magnitudes of apparent turnovers of glucose and lactate, tended to be higher during lactation than during pregnancy, while the extent of interconversions of glucose and lactate tended to be lower.3. Although the metabolic pattern seen in the cows appeared to be similar to that of the ewes during pregnancy, there were clear differences during lactation. Thus, in the lactating cows, as compared with the lactating ewes, circulating concentrations of glucose and lactate were lower, as was apparent lactate turnover related to metabolic body-weight. Furthermore, the percentage of lactate turnover converted to glucose was higher.4. In the cows, fasting was characterized by low rates of apparent turnover of glucose and lactate and relatively high rates of interconversion of the two compounds.5. The results indicated that, under the conditions used in this study and when feeding is to recommended levels, carbohydrate metabolism in ewes is more precarious during late pregnancy than during early lactation, while in dairy cows it is more or less equally precarious in both physiological states.6. A further conclusion is that the extent of glucose–lactate interconversions, and thus Cori cycle activity, seems to be lower in ruminants than in other species.


1987 ◽  
Vol 108 (2) ◽  
pp. 311-319 ◽  
Author(s):  
W. S. Dingwall ◽  
J. J. Robinson ◽  
R. P. Aitken ◽  
C. Fraser

SummaryIn Expt 1, 34 individually-penned Finn Dorset ewes of mean live weight 68 kg were synchronized in oestrus and mated to Suffolk rams. From mating until day 28 of pregnancy each received daily 15 MJ of metabolizable energy (ME) and 225 g crude protein (CP). From day 28 to slaughter on days 34, 41, 48 or 55 half of the ewes continued on this feeding regime and half had their daily intake reduced abruptly to 7·5 MJ of ME and 112 g CP. The mean number of ovulations per ewe was 4·03 (range 2–8) and the mean number of viable foetuses at time of slaughter 3·35 (range 2–6). The combined loss of ova (fertilization failure and early embryonic death) was 14·6% and detectable foetal deaths 2·2%. Level of feeding had no significant effect on these measures or on foetal growth. Foetal growth from 34 to 55 days was described by the equationIn w = 0·962–18·613 e-0·0272t–0·00091t(f–3),where w = foetal weight (kg), t = age (days) and f = litter size. Within-litter variability measured as the S.D. of In w (kg) was 0–081 for twins, 0·108 for triplets and 0·106 for quadruplets and higher multiples.In a second experiment Suffolk × Finn Dorset embryos were transplanted at the rate of two per uterine horn into 15 recipient Finn Dorset ewes. Embryo survival was 72% and foetal weights at 60 days varied from 67 to 146% of the mean value of 66 g. Withinlitter variation in foetal size was only about 70% of that expected for foetuses developing from the variable distribution in their initial positioning that occurs naturally. The correlation between foetal weight and placental weight at day 60 was 0·72 (P < 0001) indicating that the association between foetal weight and placental weight in prolific ewes is not confined to late pregnancy.The results of both experiments are consistent with the hypothesis that the greater within-litter variability in birth weight in large litters is controlled by events in early pregnancy.


2016 ◽  
Vol 1 (1) ◽  
pp. 7
Author(s):  
Banun Kusumawardani ◽  
Yuliana MD Arina ◽  
Azham Purwandhono

Periodontal disease has been involved in a variety of systemic disorders and suspected as a potential risk factor for fetal growth restriction. Periodontal pathogenic bacteria may actively regulate embryonic development, implantation and placental trophoblast cell invasion. This study aimed to analyze the role of TNF-α, IL-10 and caspase-3 to maintain fetal growth in Porphyromonasgingivalis-infected pregnant rats. Female rats were infected with live-Porphyromonas gingivalis at concentration of 2x109 cells/ml into subgingival sulcus area of the maxillary first molar before and during pregnancy. They were sacrificed on gestational day (GD)-14 and GD20. The weight and length of placentas and fetuses were evaluated. The expression of TNF-α, IL-10 and caspase-3 in macrophages and trophoblast cells were detected by immunohistochemistry. On GD14, TNF-α (R2=0.416;P=0.000) and IL-10 (R2=0.187;P=0.012) had an important role to increase expression of caspase-3 in the placenta, but only TNF-α (R2=0.393;P=0.000 ) was able to increase the expression of caspase-3 on GD20. TNF-α and caspase-3 also had an important role (P<0.000) to decrease fetal weight, fetal length and placental weight on GD14 and GD20, but it was not the case with IL-10 (P>0.000). The increasing expressions of TNF-α and IL-10 did not only enhance immune protection, but also maintained the trophoblast cells survival by regulating expression of caspase-3. Porphyromonas gingivalis infection in maternal periodontal tissue can lead to decrease in placental weight, fetal weight and fetal length which mediated by increasing expression of TNF-α, IL-10 and caspase-3 in the placenta. 


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