Offspring Mortality Research Articles

Fitness Benefits of Mate Choice for Compatibility in a Socially Monogamous Species.

Research on mate choice has primarily focused on preferences for quality indicators, assuming that all individuals show consensus about who is the most attractive. However, in some species, mating preferences seem largely individual-specific, suggesting that they might target genetic or behavioral compatibility. Few studies have quantified the fitness consequences of allowing versus preventing such idiosyncratic mate choice. Here, we report on an experiment that controls for variation in overall partner quality and show that zebra finch (Taeniopygia guttata) pairs that resulted from free mate choice achieved a 37% higher reproductive success than pairs that were forced to mate. Cross-fostering of freshly laid eggs showed that embryo mortality (before hatching) primarily depended on the identity of the genetic parents, whereas offspring mortality during the rearing period depended on foster-parent identity. Therefore, preventing mate choice should lead to an increase in embryo mortality if mate choice targets genetic compatibility (for embryo viability), and to an increase in offspring mortality if mate choice targets behavioral compatibility (for better rearing). We found that pairs from both treatments showed equal rates of embryo mortality, but chosen pairs were better at raising offspring. These results thus support the behavioral, but not the genetic, compatibility hypothesis. Further exploratory analyses reveal several differences in behavior and fitness components between “free-choice” and “forced” pairs.

Effect of metformin on maternal and fetal outcomes in obese pregnant women (EMPOWaR): a randomised, double-blind, placebo-controlled trial

SummaryBackgroundMaternal obesity is associated with increased birthweight, and obesity and premature mortality in adult offspring. The mechanism by which maternal obesity leads to these outcomes is not well understood, but maternal hyperglycaemia and insulin resistance are both implicated. We aimed to establish whether the insulin sensitising drug metformin improves maternal and fetal outcomes in obese pregnant women without diabetes.MethodsWe did this randomised, double-blind, placebo-controlled trial in antenatal clinics at 15 National Health Service hospitals in the UK. Pregnant women (aged ≥16 years) between 12 and 16 weeks' gestation who had a BMI of 30 kg/m2 or more and normal glucose tolerance were randomly assigned (1:1), via a web-based computer-generated block randomisation procedure (block size of two to four), to receive oral metformin 500 mg (increasing to a maximum of 2500 mg) or matched placebo daily from between 12 and 16 weeks' gestation until delivery of the baby. Randomisation was stratified by study site and BMI band (30–39 vs ≥40 kg/m2). Participants, caregivers, and study personnel were masked to treatment assignment. The primary outcome was Z score corresponding to the gestational age, parity, and sex-standardised birthweight percentile of liveborn babies delivered at 24 weeks or more of gestation. We did analysis by modified intention to treat. This trial is registered, ISRCTN number 51279843.FindingsBetween Feb 3, 2011, and Jan 16, 2014, inclusive, we randomly assigned 449 women to either placebo (n=223) or metformin (n=226), of whom 434 (97%) were included in the final modified intention-to-treat analysis. Mean birthweight at delivery was 3463 g (SD 660) in the placebo group and 3462 g (548) in the metformin group. The estimated effect size of metformin on the primary outcome was non-significant (adjusted mean difference −0·029, 95% CI −0·217 to 0·158; p=0·7597). The difference in the number of women reporting the combined adverse outcome of miscarriage, termination of pregnancy, stillbirth, or neonatal death in the metformin group (n=7) versus the placebo group (n=2) was not significant (odds ratio 3·60, 95% CI 0·74–17·50; p=0·11).InterpretationMetformin has no significant effect on birthweight percentile in obese pregnant women. Further follow-up of babies born to mothers in the EMPOWaR study will identify longer-term outcomes of metformin in this population; in the meantime, metformin should not be used to improve pregnancy outcomes in obese women without diabetes.FundingThe Efficacy and Mechanism Evaluation (EME) Programme, a Medical Research Council and National Institute for Health Research partnership.

Protective role of taurine in developing offspring affected by maternal alcohol consumption.

Maternal alcohol consumption is known to affect offspring growth and development, including growth deficits, physical anomalies, impaired brain functions and behavioral disturbances. Taurine, a sulfur-containing amino acid, is essential during development, and continually found to be protective against neurotoxicity and various tissue damages including those from alcohol exposure. However, it is still unknown whether taurine can exert its protection during development of central nervous system and whether it can reverse alcohol damages on developed brain later in life. This study aims to investigate protective roles of taurine against maternal alcohol consumption on growth and development of offspring. The experimental protocol was conducted using ICR-outbred pregnant mice given 10 % alcohol, with or without maternal taurine supplementation during gestation and lactation. Pregnancy outcomes, offspring mortality and successive bodyweight until adult were monitored. Adult offspring is supplemented taurine to verify its ability to reverse damages on learning and memory through a water maze task performance. Our results demonstrate that offspring of maternal alcohol exposure, together with maternal taurine supplementation show conserved learning and memory, while that of offspring treated taurine later in life are disturbed. Taurine provides neuroprotective effects and preserves learning and memory processes when given together with maternal alcohol consumption, but not shown such effects when given exclusively in offspring.

Adult Mortality Probability and Nest Predation Rates Explain Parental Effort in Warming Eggs with Consequences for Embryonic Development Time.

Parental behavior and effort vary extensively among species. Life-history theory suggests that age-specific mortality could cause this interspecific variation, but past tests have focused on fecundity as the measure of parental effort. Fecundity can cause costs of reproduction that confuse whether mortality is the cause or the consequence of parental effort. We focus on a trait, parental allocation of time and effort in warming embryos, that varies widely among species of diverse taxa and is not tied to fecundity. We conducted studies on songbirds of four continents and show that time spent warming eggs varies widely among species and latitudes and is not correlated with clutch size. Adult and offspring (nest) mortality explained most of the interspecific variation in time and effort that parents spend warming eggs, measured by average egg temperatures. Parental effort in warming eggs is important because embryonic temperature can influence embryonic development period and hence exposure time to predation risk. We show through correlative evidence and experimental swapping of embryos between species that parentally induced egg temperatures cause interspecific variation in embryonic development period. The strong association of age-specific mortality with parental effort in warming eggs and the subsequent effects on embryonic development time are unique results that can advance understanding of broad geographic patterns of life-history variation.

Association between maternal nutritional extremes and offspring mortality: A population-based cross-sectional study, Brazil, Demographic Health Survey 2006

Objectiveto estimate the association between maternal nutritional extremes and offspring mortality in the Brazilian population. Methodsthis cross-sectional study used secondary data from Brazilian women of reproductive age obtained from the National Demographic and Health Survey 2006. Maternal anthropometric indices were used: height, body mass index (BMI), and waist circumference. Logistic regression modelling was used to evaluate the relationship between obesity and offspring mortality. The data analysis was appropriate for the complex sample design. Resultschildren of mothers of short stature were at greater risk of death in the postnatal period than children of mothers of normal height, even after adjusting for sociodemographic characteristics [odds ratio (OR) 4.54, 95% confidence interval (CI) 1.31–15.77]. Maternal obesity was associated with mortality, and children whose mothers were abdominally obese were at greater risk of dying in the neonatal period (OR 3.19, 95% CI 1.23–8.27). Children of mothers who were overweight or obese (BMI≥25kg/m2) were at greater risk of dying in the neonatal period (OR 2.41, 95% CI 1.12–5.16), and children of malnourished mothers (BMI<18.5kg/m2) were at greater risk of dying during the postneonatal period (OR 9.47, 95% CI 2.07–43.41). Conclusionmaternal obesity is a risk factor for neonatal death, maternal malnutrition is a risk factor for postneonatal death, and maternal short stature is a risk factor for mortality among Brazilian children.

Altered placental DNA methylation patterns associated with maternal smoking: current perspectives.

The developmental origins of health and disease hypothesis states that adverse early life exposures can have lasting, detrimental effects on lifelong health. Exposure to maternal cigarette smoking during pregnancy is associated with morbidity and mortality in offspring, including increased risks for miscarriage, stillbirth, low birth weight, preterm birth, asthma, obesity, altered neurobehavior, and other conditions. Maternal cigarette smoking during pregnancy interferes with placental growth and functioning, and it has been proposed that this may occur through the disruption of normal and necessary placental epigenetic patterns. Epigenome-wide association studies have identified a number of differentially methylated placental genes that are associated with maternal smoking during pregnancy, including RUNX3, PURA, GTF2H2, GCA, GPR135, and HKR1. The placental methylation status of RUNX3 and NR3C1 has also been linked to adverse infant outcomes, including preterm birth and low birth weight, respectively. Candidate gene analyses have also found maternal smoking-associated placental methylation differences in the NR3C1, CYP1A1, HTR2A, and HSD11B2 genes, as well as in the repetitive elements LINE-1 and AluYb8. The differential methylation patterns of several genes have been confirmed to also exhibit altered gene expression patterns, including CYP1A1, CYP19A1, NR3C1, and HTR2A. Placental methylation patterns associated with maternal smoking during pregnancy may be largely gene-specific and tissue-specific and, to a lesser degree, involve global changes. It is important for future research to investigate the mechanistic roles that these differentially methylated genes may play in mediating the association between maternal smoking during pregnancy and disease in later life, as well as to elucidate the potential influence of emerging tobacco product use during pregnancy, including the use of electronic cigarettes, on placental epigenetics.

Supplementation with oxidised fish oil in pregnancy markedly increases neonatal mortality in male rat offspring

Omega-3 fish oils are the most popular health supplements, taken by 15-30% of people at all stages of life, including pregnancy. These oils may improve insulin sensitivity through the recently characterized GPR120 receptor, but are chemically unstable and easily degrade into potentially toxic lipid peroxides. The health effects of oxidised fish oil are mostly unknown. We have shown that 89% of fish oil products in NZ exceed recommended oxidation limits, 36% by more than two-fold. We hypothesised: 1. Fish oil supplementation during pregnancy of insulin-resistant mothers would prevent adverse metabolic programming of the offspring. 2. Oxidised fish oil would cause adverse metabolic and cardiovascular outcomes

Inflammation in maternal obesity and gestational diabetes mellitus

BackgroundThe prevalence of maternal obesity is rising rapidly worldwide and constitutes a major obstetric problem, increasing mortality and morbidity in both mother and offspring. Obese women are predisposed to pregnancy complications such as gestational diabetes mellitus (GDM), and children of obese mothers are more likely to develop cardiovascular and metabolic disease in later life. Maternal obesity and GDM may be associated with a state of chronic, low-grade inflammation termed “metainflammation”, as opposed to an acute inflammatory response. This inflammatory environment may be one mechanism by which offspring of obese women are programmed to develop adult disorders. MethodsHerein we review the evidence that maternal obesity and GDM are associated with changes in the maternal, fetal and placental inflammatory profile. ResultsMaternal inflammation in obesity and GDM may not always be associated with fetal inflammation. ConclusionWe propose that the placenta ‘senses’ and adapts to the maternal inflammatory environment, and plays a central role as both a target and producer of inflammatory mediators. In this manner, maternal obesity and GDM may indirectly program the fetus for later disease by influencing placental function.

Climate oscillations and conservation measures regulate white-faced capuchin population growth and demography in a regenerating tropical dry forest in Costa Rica

Tropical dry forests are among the world’s most imperiled biomes, and most long-lived and large-bodied animals that inhabit tropical dry forests persist in small, fragmented populations. Long-term monitoring is necessary for understanding the extent to which such populations can cope with changing climate conditions and recover after the elimination of human disturbances. We investigated how conservation measures, local rainfall patterns, and large-scale climate oscillations have affected the population dynamics of white-faced capuchins (Cebus capucinus) in a Costa Rican tropical dry forest over a 42-year period after the elimination of most human disturbances. The population’s rapid initial growth and later stabilization suggests that it was below the habitat’s carrying capacity at the time of the conservation area’s establishment. Management practices, such as aggressive fire suppression, may have played an important role in promoting this growth. Rainfall patterns were strongly coupled with phases and intensity conditions of the El Niño Southern Oscillation. The population experienced two distinct growth phases after the conservation area’s establishment, a period of rapid growth through the 1980s and 1990s and a subsequent period of stability from about 2000 to the present. El Niño-like conditions in the three years preceding a census year were associated with declines in reproductive output and/or offspring mortality during the rapid growth phase. The sensitivity of this ecosystem to global climatic phenomena suggests that some animals will be negatively affected if drought years become more common as the global climate warms.

To fledge or not to fledge: factors influencing the number of eggs and the eggs-to-fledglings rate in White Storks Ciconia ciconia in an agricultural environment

Numerous studies have explored the relationship between environmental factors and White Stork Ciconia ciconia reproduction, mainly expressing breeding success as the number of fledglings. Nonetheless, one of the most critical life-history stages in birds falls between egg-laying and fledging, and identifying the factors causing offspring mortality during this period provides valuable knowledge. We quantified the number of laid White Stork eggs and the proportion of eggs that turned into fledglings in an agriculture-dominated region in Eastern Germany. Moreover, we identified the factors among land cover, weather and arrival dates, which influenced these two reproductive measures the most, and analysed the monitored mortality causes. On average, four eggs were laid per nest, and 57.8 % of the eggs turned into fledglings. The number of eggs laid was best explained by the negative effect of the arrival date of the second stork, while the percentage of eggs that turned into fledglings was more dependent on weather: most important parameters were mean temperature in the fifth and seventh weeks after the assumed breeding start (i.e. around the assumed hatching date), and the number of consecutive days with precipitation when nestlings are assumed to be approximately 3 weeks old. In an agricultural environment, weather effects that potentially disturb food availability might be more important than effects directly affecting the survival of White Stork offspring. The most frequent observed mortality cause, nest fights, furthermore revealed the relevance of intraspecific competition in the study population.

Mortality in adult offspring of immigrants: a Swedish national cohort study.

BackgroundHigher risks of psychiatric disorders and lower-than-average subjective health in adulthood have been demonstrated in offspring of immigrants in Sweden compared with offspring of native Swedes, and linked to relative socioeconomic disadvantage. The present study investigated mortality rates in relation to this inequity from a gender perspective.MethodsWe used data from national registers covering the entire Swedish population aged 18-65 years. Offspring of foreign-born parents who were either Swedish born or had received residency in Sweden before school age (<7 years) were defined as “offspring of immigrants.” We used Cox regression models to examine the association between parental country of birth and mortality between 1990 and 2008, with adjustment for education, income, age and family type.ResultsMale offspring of immigrants from the Middle East (HR:2.00, CI:1.66-2.26), other non-European countries (HR:1.80, CI:1.36-2.36) and Finland (HR:1.56, CI:1.48-1.65) showed an age-adjusted excess mortality risk from all causes of death when compared to offspring with Swedish-born parents. Income, but not education, greatly attenuated these increased mortality risks. No excess mortality rates were found among female offspring of immigrants, with the exception of external cause of death among offspring of Finnish immigrants.ConclusionThe study demonstrates high mortality rates in male offspring of immigrants from Finland and non-European countries that are associated with economic, but not educational, disadvantage. No increased mortality rates were found among female offspring of immigrants. Future studies are needed to explain this gender differential and why income, but not education, predicts mortality in male offspring of immigrants.

Multisystem Morbidity and Mortality in Offspring of Women With Type 1 Diabetes (the EPICOM Study): A Register-Based Prospective Cohort Study.

This study examined the long-term consequences for offspring born to mothers with pregestational type 1 diabetes regarding mortality, hospital admissions, and medication. We also examined the association between HbA1c levels during pregnancy and mortality and incidence of hospital admissions. We performed a prospective combined clinical and register-based cohort study comparing mortality, hospital admissions, and use of medication in offspring (n = 1,326) of women with pregestational type 1 diabetes (index children) with matched control subjects (n = 131,884). We also examined the association between HbA1c levels during pregnancy and mortality and the incidence of hospital admissions. Participants were monitored from birth to the age of 13-21 years. Overall mortality was significantly increased for index children (hazard ratio 2.10, 95% CI 1.33-3.30, P = 0.001). The incidence of hospital admissions for index children was significantly increased (incidence rate ratio [IRR] 1.45, 95% CI 1.38-1.53, P < 0.001), and this was the case for all age groups until the age of 15 years. The incidence of hospital admissions among index children was positively associated with maternal HbA1c before pregnancy and in the first trimester. In addition, the overall use of medication was increased in index children (IRR 1.13, 95% CI 1.07-1.19, P < 0.001). Type 1 diabetes during pregnancy has long-term implications on the health of offspring, with increased mortality, incidence of hospital admissions, and use of medication. Among mothers with type 1 diabetes, glycemic regulation is positively associated with incidence of hospital admissions in offspring.

Parental effects of endocrine disrupting compounds in aquatic wildlife: Is there evidence of transgenerational inheritance?

The effects of endocrine disrupting compounds (EDCs) on aquatic wildlife are increasingly being recognized for their complexity. Investigators have detected alterations at multiple levels of biological organization in offspring exposed to EDCs through the blood or germ line of the parents, suggesting that generational consequences of EDCs are evident. Exposure to EDCs through the parents is concerning because if the resulting phenotype of the offspring is heritable and affects fitness, then evolutionary consequences may be evident. This review summarizes the evidence for transgenerational effects of EDCs in aquatic wildlife and illustrates cases where alterations appear to be transmitted maternally, paternally, or parentally. The literature indicates that EDC exposure to the parents induces developmental, physiological, endocrinological, and behavioral changes as well as increased mortality of offspring raised in clean environments. What is lacking, however, is a clear demonstration of heritable transgenerational effects in aquatic wildlife. Therefore, it is not known if the parental effects are the result of developmental or phenotypic plasticity or if the altered phenotypes are durably passed to subsequent generations. Epigenetic changes to gene regulation are discussed as a possible mechanism responsible for EDC induced parental effects. Additional research is needed to evaluate if heritable effects of EDCs are evident in aquatic wildlife, as has been demonstrated for terrestrial mammals.

Effects of Subcutaneous LPS Injection on Gestational Length and Intrauterine and Neonatal Mortality in Mice

Background: Infection during pregnancy can predispose offspring to develop various psychiatric disorders such as depression in later life. In order to investigate the potential mechanisms underlying these associations, animal models of maternal infection have been employed. As such, lipopolysaccharide (LPS) has been commonly used to mimic a bacterial infection in pregnant mice. Objective: The original aim of our study was to investigate the effects of different doses of subcutaneous LPS administration on affective behavior in adult mouse offspring. In the present paper, however, we report that subcutaneous LPS administration has a profound impact on gestational length, litter size, and perinatal mortality in the offspring, even at a relatively low dose. Methods: Pregnant mice were randomly divided into 3 groups, receiving either a high (2 mg/kg) or a low (0.5 mg/kg) dose of LPS or phosphate-buffered saline by means of subcutaneous injection. Subsequently, the effects on gestational length, litter size, and perinatal mortality in the offspring were assessed. Results: After subcutaneous injection with a high dose of LPS, we observed a significant decrease in gestational length and an increase in neonatal mortality. When the low dose was administered, a tendency towards a reduced litter size was observed, most likely reflecting increased intrauterine mortality in response to prenatal maternal LPS exposure. Conclusions: We showed that subcutaneous administration of 2 mg/kg LPS to pregnant mice in the last phase of gestation should be avoided because of high offspring mortality rates, whereas subcutaneous injection of 0.5 mg/kg LPS seems to result in reabsorption of the fetuses.

Do Offspring of Insects Feeding on Defoliation-Resistant Trees Have Better Biological Performance When Exposed to Nutritionally-Imbalanced Food?

White spruce (Picea glauca (Moench) Voss) trees that are resistant or susceptible to spruce budworm (Choristoneura fumiferana (Clem.)) attack were identified in a southern Quebec plantation. Due to high mortality-induced selective pressures imposed by resistant trees on spruce budworm larvae, insects that survive on resistant trees exhibited greater biological performance than those on susceptible trees. We tested the hypothesis that this better biological performance is maintained across generations when progeny were subjected to nutritional stress. We collected pupae from resistant and susceptible trees (phenotype). Adults were reared under controlled laboratory conditions. Progeny were subsequently reared on two types of artificial diet (high vs. low quality). Low quality diet simulated food quality deterioration during outbreak conditions. Results confirmed that surviving insects collected from resistant trees have better performance than those from susceptible trees. Offspring performance (pupal mass, developmental time) was affected only by diet quality. These results suggest that adaptive advantages that would be acquired from parents fed on resistant trees are lost when progeny are exposed to nutritionally-imbalanced food, but the effects persist when larvae are fed a balanced diet. Offspring mortality, fecundity and fertility were positively influenced by parental origin (tree phenotype).

A review of the literature on the association between vitamin D status and the risk of preeclampsia

Article type Review article Complications related to pregnancy and childbirth are the leading causes of disability and death among women of reproductive age in developing countries, constituting at least 18% of the global burden of disease in this age-group. Preeclampsia is a serious, pregnancy-specific disorder that affects up to 8% of pregnant women. Preeclampsia may lead to maternal and offspring mortality and it increases the risk of premature birth and fetal growth restriction. Vitamin D is a potent immunomodulatory agent. There is an evidence pointing toward an association between the vitamin D status and preeclampsia risk. The purpose of the present study is to review the available literature investigating the role of serum levels of vitamin D in preeclampsia. The study findings further highlight the possibility that vitamin D deficiency is a strong, independent risk factor for preeclampsia and vitamin D supplementation may be a simple step to reduce the risk of adverse pregnancy outcomes providing lifelong benefits both to the mother and her developing child.

Unexpected Use of Pupal Stage of a Lepidopteran Host by the Ectoparasitoid Wasp Agrothereutes lanceolatus (Hymenoptera: Ichneumonidae)

In general, the majority of ectoparasitoids of Lepidoptera parasitize larval and/or prepupal stages of the host and do not use the pupal stage, suggesting the presence of ecological and physiological constraints in the evolution of host range. Here, the evidence is given that Agrothereutes lanceolatus, a solitary ectoparasitoid wasp, can exceptionally parasitize host pupae, succeeding to extend its host range to pupal hosts that have a hardened cuticle. Laboratory experiments confirmed that A. lanceolatus developed successfully to adult both on host prepupae and on young pupae in equal proportions. Development time and size of the resulting wasps did not differ between the host types. However, the percentages of hosts producing wasp offspring differed among age classes within the pupal stage. The offspring survival was high except the oldest class of host pupae. With increasing host pupal ages, the offspring size decreased whereas the development time increased. Older host pupae hence were less suitable for the development of offspring. The offspring mortality mostly occurred during the 1st larval stadium without signs of growth, suggesting a difficulty in feeding on host pupae from an external position. Thus, A. lanceolatus can use a wider range of hosts than expected from its ectoparasitic development. The fact may enable A. lanceolatus to be a common and widespread polyphagous species among ectoparasitic Cryptinae.

Can Waist Circumference Be Used as an Anthropometric Parameter to Assess the Obesity Related Pregnancy Outcome: A Case Control Study

Introduction: The prevalence of obesity is increasing in women of reproductive age. Maternal obesity is associated with increased morbidity and mortality for both mother and offspring. BMI has been criticized as a limited measure of total obesity. Measurement of waist circumference can be useful in the assessment of abdominal obesity and disease risk. The study is aimed to evaluate the waist circumference as an anthropometric parameter in identifying women at risk of developing obstetric complications. Material and Methods: A prospective study was conducted at a tertiary health care centre on 200 antenatal women of age between 18 to 35 years with singleton pregnancy attending the antenatal clinic before 8 weeks of gestation. Women were divided into two groups. Group I included 100 women with waist circumference < 80 cm and Group II included 100 women with waist circumference ≥ 80 cm. Weight, height and waist circumference were measured and BMI was calculated. All the women were followed throughout their pregnancies as per the routine antenatal follow up. The fetomaternal outcome was recorded and analyzed statistically. Results: The two groups were comparable in age, parity and demographic profile. The maternal and neonatal complications—preeclampsia (p = 0.0052, RR 0.5062, 95% CI 0.2935 - 0.8728), gestational diabetes mellitus, preterm labor, postdatism, need for induction of labor (p value 0.0081, RR 0.6263, 95% CI 0.4314, 0.9091), instrumental vaginal delivery, cesarean delivery (p = 0.0072, RR 0.5745, 95% CI 0.3696, 0.8929), shoulder dystocia, PPH, macrosomia, neonatal asphyxia, admission to NICU were reported more in Group II women as compared to Group I. Conclusion: Assessment of waist circumference in early pregnancy provides a simple and practical parameter for predicting obesity related pregnancy outcome. All pregnancies in centrally obese women (waist circumference ≥ 80 cm) shall be acknowledged as high risk.

Serum total iodine concentrations in pasture-fed pregnant ewes and newborn lambs challenged by iodine supplementation and goitrogenic kale.

Iodine deficiency can impair the reproductive performance of livestock and affect perinatal mortality of offspring, yet diagnosis of deficiency is complicated and guidelines for I supplementation are imprecise. We challenged pasture-grazing pregnant ewes with a long-acting I supplement and a goitrogenic forage, then monitored their I status during gestation and lactation and in their lambs from birth to weaning. Approximately 46 d into gestation, 376 ewes were assigned to 6 groups comprising 3 supplementation levels × 2 diet regimens. On d 0 the groups received an intramuscular injection of iodized oil providing 0, 300, or 400 mg of I. They grazed until d 23, then half of each supplementation group were fed brassica kale until d 85, then all groups returned to pasture for lambing (parturition approximately d 99) and remained there until weaning (d 192). Serum total I concentration (STIC) was measured repeatedly in 8 'monitor' ewes per group and in their lambs and in milk sampled postpartum. Severity of goiter was determined as the thyroid-weight:birth-weight (TW:BW) ratio in 82 newborn dead lambs. Mean ± SE STIC for all ewes was initially 42 ± 2 (range 24 to 105) µg/L. Diet did not affect I concentrations in ewe serum or milk. Responses to iodized oil were proportional to dose level; STIC increased to approximately 150 and 240 µg/L for the 300- and 400-mg I groups and remained greater than 0-mg I groups for 161 d (P < 0.05). Milk contained 26, 271, and 425 µg I/L for the 0-, 300-, and 400-mg I groups, respectively. Mean STIC of lambs from supplemented ewes did not differ by diet; concentrations for the 300- and 400-mg I groups were 237 and 287 µg I/L at birth, and by weaning all groups were similar (62 ± 3 µg/L). Lamb STIC measured at birth correlated with exposure to I in utero (R(2) = 0.59), which was estimated from the area under the curve (AUC) of ewe STIC measured during the last 99 d of gestation. Thyroid enlargement in lambs affecting the TW:BW ratio was a sensitive indicator of maternal nutrition, being greater with kale feeding (1.27 vs. 0.51 g/kg) and lesser with I supplementation (0.35 vs. 1.44 g/kg). Results support the use of STIC as a biochemical criterion. It was sensitive to the effects of I supplementation with responses in ewes and lambs proportional to dose level and it reflected the relationship between ewe and lamb I metabolism. However STIC did not discriminate between groups of ewes fed pasture vs. goitrogenic forage during pregnancy.

Transgenerational effects of parental cardiovascular disease and risk factors on offspring mortality: family-linkage data from the HUNT Study, Norway.

Cardiovascular risk factors are known to be associated between parents and offspring. However, whether these associations are reflected in increased offspring mortality has not been extensively studied. This was a family study of 32,536 father-offspring and 39,614 mother-offspring pairs who participated in the HUNT Study, Norway. Adjusted hazard ratios (HRs) for offspring total and cardiovascular mortality associated with parental levels of cardiovascular disease risk factors were estimated using Cox regression. Fathers' and mothers' reporting of cardiovascular disease (HRs: 1.18; 95% CI 1.04-1.32 and 1.20; 1.07-1.35, respectively), diabetes (HRs: 1.22; 95% CI 1.00-1.49 and 1.21; 1.05-1.40, respectively), and current smoking (HRs: 1.21; 95% CI 1.08-1.36 and 1.30; 1.15-1.47, respectively) was associated with total mortality in offspring. An inverse association was found with maternal height (HR: 0.95; 95% CI 0.91-0.99), and a suggestive inverse association with paternal height (HR: 0.98; 95% CI 0.93-1.03). Relations with offspring cardiovascular mortality were less clear and consistent. Offspring whose parents both had a risk factor did not seem to have higher mortality than would be expected from the independent effects of each parent.