Birth Weight Of Pups Research Articles

Hexafluoropropylene oxide-dimer acid (HFPO-DA or GenX) alters maternal and fetal glucose and lipid metabolism and produces neonatal mortality, low birthweight, and hepatomegaly in the Sprague-Dawley rat

Hexafluoropropylene oxide dimer acid (HFPO-DA or GenX) is an industrial replacement for the straight-chain perfluoroalkyl substance (PFAS), perfluorooctanoic acid (PFOA). Previously we reported maternal, fetal, and postnatal effects from gestation day (GD) 14-18 oral dosing in Sprague-Dawley rats. Here, we further evaluated the perinatal toxicity of HFPO-DA by orally dosing rat dams with 1–125 mg/kg/d (n = 4 litters per dose) from GD17-21 and with 10–250 mg/kg/d (n = 5) from GD8 – postnatal day (PND) 2. Effects of GD17-21 dosing were similar to those previously reported for GD14-18 dosing and included increased maternal liver weight, altered maternal serum lipid and thyroid hormone concentrations, and altered expression of peroxisome proliferator-activated receptor (PPAR) pathway genes in maternal and fetal livers. Dosing from GD8-PND2 produced similar effects as well as dose-responsive decreased pup birth weight (≥30 mg/kg), increased neonatal mortality (≥62.5 mg/kg), and increased pup liver weight (≥10 mg/kg). Histopathological evaluation of newborn pup livers indicated a marked reduction in glycogen stores and pups were hypoglycemic at birth. Quantitative gene expression analyses of F1 livers revealed significant alterations in genes related to glucose metabolism at birth and on GD21. Maternal serum and liver HFPO-DA concentrations were similar between dosing intervals, indicating rapid clearance, however dams dosed GD8 – PND2 had greater liver weight and gestational weight gain effects at lower doses than GD17-21 dosing, indicating the importance of exposure duration. Comparison of neonatal mortality dose–response curves between HFPO-DA and previously published perfluorooctane sulfonate (PFOS) data indicated that, based on serum concentration, the potency of these two PFAS are similar in the rat. Overall, HFPO-DA is a developmental toxicant in the rat and the spectrum of adverse effects is consistent with prior PFAS toxicity evaluations, such as PFOS and PFOA.

Impact of endoplasmic reticulum stress on oocyte aging mechanisms.

Endoplasmic reticulum (ER) stress is associated with several aging-related diseases; however, the mechanism underlying age-related deterioration of oocyte quality is unclear. Here, we used post-ovulatory, in vivo aged mouse oocytes as a model. Super-ovulated oocytes harvested from the oviduct at 14 h and 20 h post-hCG injection were designated as 'fresh' and 'aged', respectively. Embryo development following IVF was compared between fresh, aged and ER stress-induced oocytes. Expression of the ER stress marker GRP78 was examined at each stage. To evaluate the effect of salubrinal, an ER stress suppressor, on embryo development following IVF, expression levels of GRP78 and phospho-eukaryotic initiation factor 2 alpha were compared between aged and salubrinal-treated aged oocytes. Embryo transfer of salubrinal-treated aged oocytes was performed to examine the safety of salubrinal. Similar to aged oocytes, ER stress-induced oocytes showed lower fertilization rates and poor embryo development. Following IVF, expression of GRP78 decreased with embryo development. GRP78 expression was significantly higher in aged oocytes than in fresh oocytes. Salubrinal lowered GRP78 levels and improved embryo development. No adverse effect of salubrinal treatment was found on the birth weight of pups or on organogenesis in mice. The limitation of this study was that protein kinase-like ER kinase was the only ER stress pathway examined; the role of IRE1 and ATF6 pathways was not considered. Nevertheless, salubrinal can significantly improve embryo development in in vivo aged oocytes undergoing ER stress. Hence, regulation of ER stress might represent a promising therapeutic strategy to overcome poor oocyte quality.

Beneficial effect of symbiotic supplementation during pregnancy in high fat diet-induced metabolic disorder in rats: Role of Chemerin

ObjectiveMetabolic disorders during pregnancy have detrimental effect on mother and her fetus. Symbiotic supplementation can improve metabolic disorders. The aim of this study was to assess the impact of symbiotic supplementation on the levels of Chemerin, lipid profile, glucose, and insulin resistance in pregnant rats fed a high-fat diet (HFD). Materials and methodsThirty female Wistar rats (weighing 200–220 g) were randomly assigned into three groups: control group, HFD group, and HFD + symbiotic group. The control group received the regular diet (fed lab chow); the HFD group received HFD alone; and the HFD + symbiotic group that in addition to taking HFD, was gavaged daily during pregnancy with a symbiotic solution, which contained Lactobacillus rhamnosus and Bacillus coagulans at a concentration of 108 CFU/ml and fructooligosaccharide 10%. On the 10th day of the experiment, the animals became pregnant. At the end of pregnancy period, birth weight of offspring, levels of blood glucose, total cholesterol, triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), insulin, and chemerin level were measured. ResultsBirth weight of offspring in the HFD + symbiotic group was significantly lower than in the HFD group (P < 0.02). Similarly, insulin, insulin resistance, TG, total cholesterol, and LDL levels in the HFD + symbiotic group were significantly lower than in the HFD group (all P < 0.01). Symbiotic supplementation significantly reduced chemerin concentration in HFD + symbiotic group than HFD group (P < 0.008). Chemerin levels had a significant and positive correlation with food intake in the first ten days of the experiment and gestation period (P < 0.01, P < 0.04), fasting blood sugar (FBS) (P < 0.01), Total cholesterol (P < 0.05) and homeostatic model assessment (HOMA) index (P < 0.01). Moreover, chemerin levels had a significant and negative correlation with HDL (P < 0.01) and insulin (P < 0.02) levels. ConclusionBased on our results, symbiotic supplementation has beneficial effects on metabolic disorders and improves weight gain during pregnancy, pup birth weight, FBS, insulin resistance and lipid profile. These advantages of symbiotic supplementation could be mediated by change in chemerin secretion.

Natural cocoa improves birth weight and viability of rabbit pups born to hypercholesterolemic mothers

BackgroundMaternal nutrition affects fetal growth and development in humans and animals. Low birth weight can be caused by maternal hypercholesterolemia and is associated with increased risk of cardiovascular and other metabolic diseases later in adult life. Cocoa powder is rich in flavonoids and reduces plasma cholesterol levels. The study investigated the effect of hypercholesterolemia and natural cocoa intake during pregnancy on the birth weight and viability of rabbit pups. MethodsHypercholesterolemic female New Zealand White rabbits were crossed with normocholesterolemic males and randomly grouped into 2 (n = 4 each). One group (HCC) received natural cocoa powder in their water in addition to high cholesterol diet during pregnancy, whereas the other (HC) received only water and high cholesterol diet. Litter size, birth weight and viability of pups were assessed and compared to a control group (NC) fed normal rabbit chow (n = 2). ResultsAverage litter sizes of hypercholesterolemic rabbits (HC and HCC groups) were 3, whereas that of control group, NC was 5. Mean birth weight of pups was significantly lower in offspring of HC (42.73 g, SD 8.47) and HCC (50.0 g, SD 3.54) as compared to NC (73.0 g, SD 5.37). Mortality of offspring was highest in HC group (58.3%) as compared to 50% in HCC. ConclusionsMaternal hypercholesterolemia during pregnancy reduces litter size, birth weight and viability of offspring in rabbits and these deleterious effects may be minimized by regular intake of natural cocoa. Although further studies in humans need to be conducted, the results of this study suggest the need to monitor maternal cholesterol levels during pregnancy and the effects on pregnancy outcomes and health of offspring later in life.

The Effects of Nicotine on Foetal Loss, Postnatal Growth and Plasma Oestrogen and Progesterone Levels in Rats

Introduction: The present study aims to investigate the effects of nicotine on foetal loss, postnatal growth and corresponding levels of oestrogen and progesterone in pregnant rats. Method: Subcutaneous injection of nicotine tartrate (7.5 mg/kg/day) was administered to groups of pregnant rats; with treatment scheduled from day 1 through day 5, day 5 through day 9 or day 1 through day 9 of pregnancy. On day 10 of pregnancy, laparotomy was performed to count the number of blastocyst implantation sites. During parturition, the number of viable pups was recounted and statistically compared with the controls. One group of rats which received nicotine from day 1 through day 9 of pregnancy was sacrificed on day 16 of pregnancy, and circulating levels of oestrogen and progesterone were measured. Upon delivery, the birth weight of the pups was measured, and their weights were recorded until weaning. Result: There was a significant increase in foetal loss particularly in rats which received nicotine from day 5 through day 9 and from day 1 through day 9 of pregnancy. There was also significantly lower birth weight of pups in all groups; however, this pattern did not continue until weaning. Plasma oestrogen level was significantly elevated with a significant decrease in the plasma progesterone level. Conclusion: Nicotine administration during pregnancy showed an increase in foetal loss with a corresponding increase in oestrogen and decrease in progesterone levels. Although the birth weight of the pups was low, there was catch-up growth in the pups.

1211 Beta-hydroxy-beta-methylbutyrate (HMB) supplementation to mouse dams in gestation does not affect birth weight variation or growth of offspring

Abstract The objective of this study was to determine if supplementing diets with β-hydroxy-β-methylbutyrate (HMB) calcium salt for mouse dams throughout gestation would improve pup birth weight uniformity and growth performance of offspring. Dams were assigned to one of 4 treatments as follows: control (CON; n = 6), Low Level HMB (LL; 3.5 mg/g diet; n = 7), High Level HMB (HL; 35 mg/g diet; n = 8), and Low Level Pulse fed from gestational days 6 to 10 (PUL; 3.5 mg/g diet; n = 7). Supplementation began at mating and continued until birth. Dams gave birth and lactated for 28 days. Offspring were reared until 8 weeks of age. All mice had ad libitum access to a corn-soybean meal diet, with HMB supplementation provided only to dams during gestation. Supplementation of HMB had no effects on overall gestation and lactation performance of mouse dams. Dietary treatment during gestation did not affect total number of pups born per litter, birth weight of pups, or number weaned. Within litter variation, expressed as standard deviation and coefficient of variation, was not different among treatments for birth weight or weaning weight. Range of body weights within litter at birth, weaning, and 8 weeks of age were not affected by HMB supplementation. Overall, offspring growth performance was similar among treatments. However, body weight at 5 and 8 weeks of age was lower for offspring from the HL dams compared to offspring from LL dams (P &amp;lt; 0.05). Body composition of offspring at 5 and 8 weeks of age was similar regardless of HMB supplementation in dam diets during gestation. In conclusion, dietary HMB supplementation of mouse dams during gestation had no effect on birth weight of offspring, variation in birth weight, or growth performance of offspring.

Maternal Folik Asit Suplemantasyonunun Rat Yavrularında Doğum Ağırlığı ve Obezite Gelişimi Üzerine Etkilerinin Değerlendirilmesi

Amaç: Bu çalışmada gebelik boyunca farklı miktarlarda folik aside (FA) maruz bırakılan rat yavrularının doğum ağırlığı ile obezite gelişimi üzerine etkilerinin değerlendirilmesi amaçlanmıştır.&#x0D; Gereç ve Yöntem: Wistar türü dişi ratların (n=18) gebe kalmaları sağlanmış ve randomize şekilde üç gruba ayrılmıştır. Gebelik döneminde her gruba FA içerikleri farklı üç ayrı beslenme protokolü (Kontrol grubu [KG]: 2 mg/kg folik asit, Deney 1 grubu [D1]: 5 mg/kg folik asit, Deney 2 grubu [D2]: 40 mg/kg folik asit) uygulanmıştır. Kontrol ve deney grubu yavruların doğum ağırlığına bakılmıştır. Laktasyon dönemi sonrasında her gruptan 12 yavru (6 dişi ve 6 erkek) olmak üzere toplamda 36 yavrunun haftalık vücut ağırlığı takibi yapılmıştır. Yedi ve on ikinci haftaların sonunda yavruların obezite durumu (Lee indeksi) değerlendirilmiştir. Çalışmaya toplamda 18 anne ve 36 yavru olmak üzere 54 rat dahil edilmiştir.&#x0D; Bulgular: En yüksek ortalama doğum ağırlığının, D2 grubundaki ratlardan doğan yavrularda olduğu belirlenmiştir (KG: 5.6±0.1 g; D1: 5.8±0.5 g; D2: 5.9±0.2 g; p&lt;0.05). D2 grubu erkek (174.4±5.6 g) ve dişi (138.3±7.7 g) yavruların yedinci haftanın sonundaki vücut ağırlıklarının, KG (erkek: 151.6±10.6 g; dişi: 124.6±3.9 g) ve D1 grubundaki (erkek: 163.3±25.3 g; dişi: 130.8±13.0 g) yavrulardan daha yüksek olduğu belirlenmiştir (p&lt;0.05). On ikinci hafta sonundaki erkek ve dişi yavruların ortalama vücut ağırlıkları ve vücut ağırlığı artışları benzer bulunmuştur (p&gt;0.05). Yüksek miktarda folik aside maruz kalan annelerin yavrularının yedi haftalık iken vücut ağırlıkları normal aralıkta olmasına rağmen, on ikinci haftanın sonunda dişi yavruların tamamının, erkek yavruların ise üçte birinin obez olduğu (%33.3) belirlenmiştir.&#x0D; Sonuç: Bu çalışma, maternal FA suplemantasyon miktarının yavru ratlarda vücut ağırlığı artışıyla ilişkili bir risk faktörü olabileceğini ve yavrularda obeziteye yatkınlığa neden olabileceğini düşündürmüştür. Gebelerde FA suplemantasyonu uygulamasında doza dikkat edilmelidir.

Effect of variously-processed rubber seed meals on reproductive performance: The use of Sprague-Dawley laboratory rats as model for pigs

The study aimed to determine the potential adverse effects of variously-processed rubber seed meals on the reproductive performance, postnatal growth and offspring survival rate using the Sprague-Dawley laboratory rat as model for pigs. Eighteen Sprague-Dawley female rats with an average initial body weight of 154.0 g were randomly allotted into 6 groups designated as T1 control (no rubber seed meal), T2 raw rubber seed meal, T3 soaked rubber seed meal, T4 sundried rubber seed meal, T5 boiled rubber seed meal and T6 roasted rubber seed meal. The diets were prepared with various types of rubber seed meals incorporated at the level of 0 g kg-1 (control diet, T!) and 100 g kg-1 of each of the five rubber seed meal-containing diets. The study was conducted for 70 days and parameters studied included: feed intake, number of fertile females, pregnancy index, gestation length (length of pregnancy), number of pups born, number of pups born alive, live birth index and number of still births. Upon parturition (day 1), pups were individually counted, weighed and examined for external malformations. Other parameters evaluated were number of pubs weaned and mortality of pups. The inclusion of various types of rubber seed meals in the diets did not alter the general health of all the experimental rats. With the exception of rats on the T6 diet, all other rats recorded successful mating and pregnancies. There were no significant (p&gt;0.05) difference in the gestation length (22 to 23 days) and all the pregnant rats delivered normally. No external malformations were observed in any of the pups delivered. No significant (p&gt;0.05) differences in the maternal body weight (199.8 g), litter size (4.0 to 10), pup birth weight (4.88 to 7.07 g) and number of pups weaned (3.33 to 9.67) were observed. However, dietary treatments significantly (p&lt;0.05) influenced weaning weight (29.60 to 48.25 g) and post-natal mortality of pups, with those on the T1 (control) and the T4 diets having the highest mortalities of 2.67 and 2.33, respectively. Based on the findings of the present study, up to 100 g of the raw and the variously-processed rubber seed meals could be included in 1 kg diets of laboratory rats without compromising on the health and reproductive performance in terms of reproductive toxicity or complications in pregnancy, delivery and other reproductive indices studied.

Levothyroxine supplementation in hypothyroid bitches during pregnancy

Hypothyroidism is the most common endocrine disease in dogs and has been shown to have a hereditary nature in many breeds. Previous studies have documented decreased fertility in bitches with experimentally-induced hypothyroidism, decreased viability at birth, increased periparturient mortality, and reduced birth weight in pups born to hypothyroid dogs. Hypothyroid women have an increased demand for exogenous thyroxine throughout gestation in order to maintain normal plasma concentrations of thyroid hormones and produce neuropsychologically normal children. This study was performed to determine if pregnancy causes a similar need for increased levothyroxine dosages in dogs to maintain a euthyroid state. Serum was harvested from blood collected from six bitches with experimentally-induced hypothyroidism that were receiving standard thyroid hormone replacement therapy and from four euthyroid control bitches. Thyroid function tests performed on these samples included total thyroxine (T4), free T4 (fT4), thyroid stimulating hormone (TSH), and 3,5,3′-triiodothyronine (T3). Thyroid function tests were measured from ovulation through the end of pregnancy. All bitches whelped normal litters. Euthyroid bitches had no significant alterations in their hormone concentrations throughout pregnancy. None of the supplemented hypothyroid bitches had clinical signs of hypothyroidism throughout the study. Serum concentrations of T4 and fT4 were elevated compared to ovulation at multiple sample points during gestation in supplemented dogs. The results from this study indicate that standard levothyroxine supplementation is adequate to maintain a euthyroid state during pregnancy in experimentally-induced hypothyroid dogs. In addition, there is no evidence that canine thyroid profiles in euthyroid dogs are altered during gestation.

Effect of docosahexanoic acid (DHA) supplementation on the birth weight of rat pups prenatally exposed to alcohol.

Effect of docosahexanoic acid (DHA) supplementation on the birth weight of rat pups prenatally exposed to alcohol.

Paternal THC exposure in rats causes long-lasting neurobehavioral effects in the offspring

Developmental neurotoxicity of a wide variety of toxicants mediated via maternal exposure during gestation is very well established. In contrast, the impacts of paternal toxicant exposure on offspring neurobehavioral function are much less well studied. A vector for paternal toxicant exposure on development of his offspring has been identified. Sperm DNA can be imprinted by chemical exposures of the father. Most but not all of the epigenetic marks in sperm are reprogrammed after fertilization. The persisting epigenetic marks can lead to abnormal genetic expression in the offspring. We have found that paternal delta-9-tetrohydrocannabinol (THC) exposure in rats causes changes in methylation of sperm (Murphy et al., 2018). This is similar to cannabis-associated changes in sperm DNA methylation we found in human males who smoke cannabis (Murphy et al., 2018). In the current study we investigated the intergeneration effects of THC exposure of young adult male rats (0 or 2 mg/kg/day orally for 12 days) to the neurobehavioral development of their offspring. This paternal THC exposure was not found to significantly impact the clinical health of the offspring, including litter size, sex ratio, pup birth weight, survival and growth. However, it did cause a long-lasting significant impairment in attentional performance in the offspring relative to controls when they were tested in adulthood. There was also a significant increase in habituation of locomotor activity in the adult offspring of the males exposed to THC prior to mating. This study shows that premating paternal THC exposure even at a modest dose for a brief period can cause deleterious long-term behavioral effects in the offspring, notably significant impairment in an operant attention task. Further research should be conducted to determine the degree to which this type of risk is seen in humans and to investigate the mechanisms underlying these effects and possible treatments to ameliorate these long-term adverse behavioral consequences of paternal THC exposure.

The Effect of Maternal Intact Protein- and Amino Acid-Based Diets on Development of Food Intake Regulatory Systems and Body Weight in Dams and Male Offspring of Wistar Rats.

The objective of this study is to examine the effect of maternal and weaning intact protein- and amino acid-based diets on regulation of food intake, intake regulatory hormones, and body weight in dams and their male offspring. Pregnant Wistar rats were allocated to two groups (n = 12) and were fed either an intact protein diet (IPD) or mixed amino acid diet (AAD) from day 3 of gestation throughout gestation and lactation. Male offspring were weaned to either an IPD or AAD for 18 weeks. Food intake (FI) and body weight (BW) were measured weekly. Results: In dams, the AAD group had lower FI and BW in the post-partum period compared with the IPD group. In pups born to AAD dams, birth weight and BW were lower. However, the percentage of fat and lean mass were not affected. Food intake was influenced by maternal diet and was higher in pups born to IPD dams throughout post-weaning. Short-term FI in response to protein preloads was lower in pups born to AAD dams in 1 h. Fasting plasma concentrations of glucose, insulin, and ghrelin were not influenced by either maternal or weaning diet. However, peptide YY (PYY) was higher in pups born to IPD dams at weaning. Conclusions: The physicochemical properties of proteins fed during pregnancy and lactation had determining effects on the body weight and development of food intake regulatory systems in offspring. Maternal AAD resulted in lower BW in dams and lower birth weight and post-weaning BWs in pups compared with maternal IPD which was consistent with their lower FI.

Role of maternal folic acid on implantation of embryos and on maternal body weight &amp; offspring's birth weight

Introduction There has been a much debate on the role of pre-/periconceptional and prenatal folic acid (FA) supplements for the long-term health of their offspring. Maternal deficiency of FA or excess of FA would likely to affect the developing fetus at critical stages of development to cause long-lasting health consequences in their offspring. The present study aimed to know the effect of folic acid supplementation and folic acid absence diet during pregnancy on the number of implantation, endometrial changes at the implantation site and on maternal body weight & offspring's birth weight. Material & Methods Thirty-Six Wistar strained female rats were approved for experimental use by the Institutional Animal Ethical Committee. Rats were randomly divided into two groups with 18 rats in each group. Further, each group has been divided into three sets with 6 rats in each. The control set was fed a normal diet, the second set was fed a diet containing no FA. 1% Succinyl sulfathiazole was added to the diet with no FA content to reduce/ inhibit the gut flora responsible for the synthesis of FA in their body. The third set was given diet with an excess of FA (40mg/kg body weight/day). Rats were given respective diet for 4 weeks before mating, continued throughout their pregnancy and 5 weeks after the delivery of pups (weening period). All female rats were paired with males of their own strain overnight at room temperature (25°C). To check whether they mated or not, the vaginal smear was taken in the early morning and stained with methylene blue and confirmed the presence of sperm plug under microscopy. On confirmation of sperm plug, the gestational day was termed as day 1 (GD1). Rats have remained in their cage and diets until they were sacrificed during gestation from day GD6-GD9. Rats were remained in their cage and with their respective diets until they delivered the pups. Delivered pups were counted for each rat and gross malformation in each pup was noted. Immediately after the delivery, all the pups born to each rat were weighed individually in the digital weighing machine. Results Average number of pups born to pregnant dams fed with FA supplementation, FA absent diet, and in normal diet was found to be 8,8, and 9 respectively. Regarding the birth weight of pups born to pregnant dams fed with FA supplementation the average weight was found to be 6.01-5.09 gm, with evidence diet it was 5.51-5.08 gm, and least weight was observed in pups born with FA absent diet (4.74-3.31 gm). Pair-wise comparison was done to correlate the significant association between the different groups. It showed significant difference when compared with pups born to FA supplementation diet to pups born to FA absent diet. Also, significant differences were noted when compared pups born to FA absent diet mother with pups born to FA supplementation and with pups born to normal diet. Conclusion Our study provides clear evidence that FA is essential in successful implantation by providing favorable receptive environment to receive the implantation-competent blastocyst for a successful pregnancy. Birth weight of pups born to pregnant dams fed with FA supplementation was found to be significantly increased when compared to those with the diet with normal amount of FA, and least weight wasobserved in pups born with FA absent diet. As the fetal birth weight is the best predictor of pregnancy outcome as the growth restriction has been associated with high morbidity and mortality. FA supplementation is essential during the period of pregnancy to prevent untoward effects on pregnancy-related complications in mother and to prevent birth defects in fetuses. Further research from longitudinal studies is warranted to confirm these results before its recommendation to the public health.

POSSIBILITIES OF LECTIN HELIX POMATIA AGGLUTININ (HPA) USE IN RABBITS INSEMINATION

The aim of this work was to analyse the effect of incubation HPA (lectin Helix pomatia agglutinin) with ID (insemination dose) on reproduction parameters (conception ratio, number of live and dead born of pups and birth weight of pups) of rabbits. The experiments were carried out under conditions of 2 rabbit breeds (production breed P and experimental breed E). Fresh ID, in sperm concentrations 25 mil. / 0.5 ml ID, were divided into control ID (without HPA) and experimental ID (with HPA). HPA was added to the experimental ID in concentrations 1µg HPA / 1x106 spermatozoa (30 - 60 minutes of incubation before AI – artificial insemination). Conception ratios obtained from 2 different breeds (P, E) showed minor improvement ( + 2.67 % P; + 7.36 % E) between the monitored groups of females, however without statistically significant differences (P χ2 = 0.03; E χ2 = 0.11). Number of live born pups in litter obtained from breeds P and E showed minor improvement (+ 0.37 pcs P (p&gt;0.05); + 0.95 pcs E (p≤0.05)) compared to the control groups. The weight of live pups among the monitored groups was comparable. It can be concluded from the present study that incubation of ID with lectin HPA had been positively affected by the observed reproductive parameters. The statistically significant difference was found only in the number of live-born pups in the litter. The price of lectin is too high for breeding in common breeding practice.

Commentary on the utility of the National Toxicology Program study on cell phone radiofrequency radiation data for assessing human health risks despite unfounded criticisms aimed at minimizing the findings of adverse health effects

The National Toxicology Program (NTP) conducted two-year studies of cell phone radiation in rats and mice exposed to CDMA- or GSM-modulated radiofrequency radiation (RFR) at exposure intensities in the brain of rats that were similar to or only slightly higher than potential, localized human exposures from cell phones held next to the head. This study was designed to test the (null) hypothesis that cell phone radiation at non-thermal exposure intensities could not cause adverse health effects, and to provide dose-response data for any detected toxic or carcinogenic effects. Partial findings released from that study showed significantly increased incidences and/or trends for gliomas and glial cell hyperplasias in the brain and schwannomas and Schwann cell hyperplasias in the heart of exposed male rats. These results, as well as the findings of significantly increased DNA damage (strand breaks) in the brains of exposed rats and mice, reduced pup birth weights when pregnant dams were exposed to GSM- or CDMA-modulated RFR, and the induction of cardiomyopathy of the right ventricle in male and female rats clearly demonstrate that the null hypothesis has been disproved. The NTP findings are most important because the International Agency for Research on Cancer (IARC) classified RFR as a “possible human carcinogen” based largely on increased risks of gliomas and acoustic neuromas (which are Schwann cell tumors on the acoustic nerve) among long term users of cell phones. The concordance between rats and humans in cell type affected by RFR strengthens the animal-to-human association. This commentary addresses several unfounded criticisms about the design and results of the NTP study that have been promoted to minimize the utility of the experimental data on RFR for assessing human health risks. In contrast to those criticisms, an expert peer-review panel recently concluded that the NTP studies were well designed, and that the results demonstrated that both GSM- and CDMA-modulated RFR were carcinogenic to the heart (schwannomas) and brain (gliomas) of male rats.

Rank‐based inference for covariate and group effects in clustered data in presence of informative intra‐cluster group size

There have been numerous attempts to extend the Wilcoxon rank-sum test to clustered data. Recently, one such rank-sum test (Dutta & Datta, 2016, Biometrics 72, 432-440) was developed to compare the group-specific marginal distributions of outcomes in clustered data where the conditional distributions of outcomes depend on the number of observations from that group in a given cluster, a phenomenon referred to as informative intra-cluster group (ICG) size. However, comparison of group-specific marginal distributions may not be sufficient in presence of some potentially useful covariables that are observed in the study. In addition, not accounting for the effect of these covariates can lead to biased and misleading inference for the group comparisons. Thus, the purpose of this article is twofold. First, we develop a method to estimate the covariate effects using rank-based weighted estimating equations that are appropriate when the ICG size is informative. Second, we construct an aligned rank-sum test based on the covariate adjusted outcomes. Asymptotic distributions of the R-estimators and the test statistic are provided. Through simulation studies, we show the importance of selecting proper weights in constructing the estimating equations when informativeness is present through the cluster or ICG sizes. We also demonstrate the superiority and the robustness of our method in comparison to regular parametric linear mixed models in clustered data. We apply our method to analyze different real-life data sets including a data on birthweights of rat pups in different litters and a dental data on tooth attachment loss.

Perfluorohexane Sulfonate (PFHxS) and a Mixture of Endocrine Disrupters Reduce Thyroxine Levels and Cause Antiandrogenic Effects in Rats.

The developmental toxicity of perfluorohexane sulfonate (PFHxS) is largely unknown despite widespread environmental contamination and presence in human serum, tissues and milk. To thoroughly investigate PFHxS toxicity in developing rats and to mimic a realistic human exposure situation, we examined a low dose close to human relevant PFHxS exposure, and combined the dose-response studies of PFHxS with a fixed dose of 12 environmentally relevant endocrine disrupting chemicals (EDmix). Two reproductive toxicity studies in time-mated Wistar rats exposed throughout gestation and lactation were performed. Study 1 included control, two doses of PFHxS, and two doses of PFHxS + EDmix (n = 5-7). Study 2 included control, 0.05, 5, or 25 mg/kg body weight/day PFHxS, EDmix-only, 0.05, 5, or 25 mg PFHxS/kg plus EDmix (n = 13-20). PFHxS caused no overt toxicity in dams and offspring but decreased male pup birth weight and slightly increased liver weights at high doses and in combination with the EDmix. A marked effect on T4 levels was seen in both dams and offspring, with significant reductions from 5 mg/kg/day. The EDmix caused antiandrogenic effects in male offspring, manifested as slight decreases in anogenital distance, increased nipple retention and reductions of the weight of epididymides, ventral prostrate, and vesicular seminalis. PFHxS can induce developmental toxicity and in addition results of the co-exposure studies indicated that PFHxS and the EDmix potentiate the effect of each other on various endpoints, despite their different modes of action. Hence, risk assessment may underestimate toxicity when mixture toxicity and background exposures are not taken into account.

Reproductive failure in mice expressing transgenic follicle-stimulating hormone is not caused by loss of oocyte quality.

Human female reproductive aging features declining ovarian follicle reserve and oocyte quality, and rising levels of circulating follicle-stimulating hormone (FSH). We determined the effects of elevated FSH on oocyte-embryo development in mature mice exhibiting premature infertility caused by progressively rising transgenic human FSH (TgFSH) levels. Oocyte-embryo developmental competence and quality were examined using oocyte maturation and aneuploidy rates, biomarkers of oocyte quality, and reciprocal embryo transfers assessed for implantation and pregnancy. In vitro maturation suggested that TgFSH exposure only hindered oocyte developmental competence in old females, as significantly more oocytes from ≥12-month-old TgFSH females remained at germinal vesicle stage compared with age-matched control oocytes. Aneuploidy rates were equivalent in oocytes from aging TgFSH compared with wildtype females. Cumulus cell expression levels of candidate biomarker Inhba, Egfr, and Rgs2 transcripts were elevated in associated aneuploid vs euploid oocytes from both TgFSH and wildtype females. In vivo, embryos transferred from subfertile 6-month-old TgFSH females to wildtype recipients yielded normal implantation rates and more pups born compared with controls. Transfer of wildtype embryos rescued the fertility of 6-month-old TgFSH-recipient females, although pup birth weight was reduced in TgFSH vs wildtype recipients. Our current findings show that elevated FSH had minimal disruption of either embryo developmental capacity or uterine function when examined in isolation, and the subfertility of TgFSH female mice was not caused by altered oocyte aneuploidy or quality.

Identification of early indicators of altered metabolism in normal development using a rodent model system.

ABSTRACTAlthough the existence of a close relationship between the early maternal developmental environment, fetal size at birth and the risk of developing disease in adulthood has been suggested, most studies, however, employed experimentally induced intrauterine growth restriction as a model to link this with later adult disease. Because embryonic size variation also occurs under normal growth and differentiation, elucidating the molecular mechanisms underlying these changes and their relevance to later adult disease risk becomes important. The birth weight of rat pups vary according to the uterine horn positions. Using birth weight as a marker, we compared two groups of rat pups – lower birth weight (LBW, 5th to 25th percentile) and average birth weight (ABW, 50th to 75th percentile) – using morphological, biochemical and molecular biology, and genetic techniques. Our results show that insulin metabolism, Pi3k/Akt and Pparγ signaling and the genes regulating growth and metabolism are significantly different in these groups. Methylation at the promoter of the InsII (Ins2) gene and DNA methyltransferase 1 in LBW pups are both increased. Additionally, the Dnmt1 repressor complex, which includes Hdac1, Rb (Rb1) and E2f1, was also upregulated in LBW pups. We conclude that the Dnmt1 repressor complex, which regulates the restriction point of the cell cycle, retards the rate at which cells traverse the G1 or G0 phase of the cell cycle in LBW pups, thereby slowing down growth. This regulatory mechanism mediated by Dnmt1 might contribute to the production of small-size pups and altered physiology and pathology in adult life.

Effect of Folic Acid Supplementation and/or its Absence on Body Weight of Wistar Rats in Pregnancy and in their Offspring

Introduction: Foetal birth weight is the best predictor of pregnancy outcome as the growth restriction has been associated with high morbidity and mortality. The need of Folic Acid (FA) supplementation is essential during the period of pregnancy to prevent untoward effects on pregnancy related complication in mother and to prevent birth defects in foetus. Aim: To compare the effects of FA supplementation and FA absent diets during the pregnancy on maternal and their offspring body weight. Materials and Methods: This was a prospective study comprising of 18 Wistar albino rats procured from the Animal house, Manipal Academy of Higher Education, Karnataka, India, after the institutional ethical committee clearance. Rats were randomly divided into three groups and given different diets: Control group with normal diet, group with FA supplementation diet, and group with FA absent diet (with added succinyl sulfathiazole) for five weeks. Later the female adult Wistar rats could mate with male rats of their own strain and allowed the female to complete their pregnancy. After the delivery, delivered pups were counted for each rat and gross malformation in each pup were noted. Immediately after the delivery, all the pups born to each rat were weighed individually in digital weighing machine. Results: Among the pregnant dams the body weight gain was observed more in control group with an average weight of 40.56 gm, followed by diet with absent FA (32 gm) and least in rats fed with FA supplementation diets (31 gm). Average number of pups born to pregnant dams fed with FA supplementation, FA absent diet, and in normal diet was found to be 8, 8, and 9 respectively. Regarding the birth weight of pups born to pregnant dams fed with FA supplementation the average weight was found to be 6.01-5.09 gm, with normal diet it was 5.51-5.08 gm, and least weight was observed in pups born with FA absent diet (4.74-3.31 gm). Conclusion: The present study concluded that the FA status in pregnancy is inversely proportional to the prenatal death in pups but in offspring’s born to mothers fed with FA supplementation, average body weight was more than those born to mothers fed with FA absent diet and with control groups. However, this needs further confirmation as the tests were done on limited samples.