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PubMed1999

Resistance of Eisenia fetida (Oligochaeta) to cadmium after long-term exposure.

The reliance on earthworms as test organisms in risk assessment studies of polluted environments raises the question whether they can evolve resistance, e.g., by adaptation to specific toxicants. Protection criteria may be biased if sensitivity data from adapted populations are used. Increased resistance to the heavy metal cadmium has not yet been determined for terrestrial Oligochaeta. Eisenia fetida was exposed to a sublethal concentration of cadmium sulfate for more than 10 generations. Clitellate worms from this culture were used in experiments to determine the extent of possible tolerance for the heavy metal. Preexposed animals as well as worms with no previous history of exposure to cadmium were exposed to a control substrate without cadmium and also to two substrates with 600 and 1200 microg g-1 cadmium. Changes in biomass, cocoon production, and hatching success were monitored. The results obtained indicated that in both substrates in which cadmium was present the preexposed worms performed better than the unexposed worms with respect to growth rate but not reproductively. In the substrate without cadmium the preexposed worms exhibited signs of poisoning after a few weeks. Preexposed and unexposed worms were also exposed to concentrations of 1500 to 4000 microg g-1 cadmium sulfate in an artisol medium for a period of 2 weeks. The preexposed worms survived higher concentrations of cadmium than the unexposed group and some specimens from the unexposed group had a gross increase in body fluids. It is concluded that worms with a long-term history of exposure to the metal developed resistance to cadmium.

Animals↗
PubMed1975

Growth and Development of Soybean (Glycine max [L.] Merr.) Pods: CO(2) Exchange and Enzyme Studies.

The rates of CO(2) exchange and (14)CO(2) incorporation in the light and dark and the activities of several photosynthetic, photorespiratory, and respiratory enzymes of soybean (Glycine max [L.] Merr. cv. Wye) reproductive structures were determined at weekly intervals from anthesis to pod maturity. At all stages of pod development soybean reproductive structures were found to be incapable of net photosynthesis under the experimental conditions employed, but capable of gross photosynthesis and light-induced (14)CO(2) uptake. Consistent with the lack of net photosynthesis throughout the development of the reproductive structure, the maximum in vitro activity of ribulose 1,5-bisphosphate carboxylase (EC 4.1.1.39) in pod tissue was only 3% of that in leaf extracts when expressed on a fresh weight basis. We concluded that the major role of the reproductive structure of the soybean with respect to photosynthetic carbon metabolism is the reassimilation of its respiratory CO(2).

Journal Article↗
PubMed1986

Environmental factors and cancer mortality in Italy: correlational exercise.

Mortality rates for 21 cancer sites in 20 Italian regions have been correlated with several economic and dietary variables (including alcohol and coffee consumption), patterns of cigarette smoking and reproductive habits. In both sexes, a large number of strong correlations emerged, the most notable ones being the strong positive coefficients between cigarettes sold in the early 1950s and lung cancer mortality in middle-aged males in the early 1970s, between gross internal product or meat consumption and cancer of the intestines in both sexes, between total per caput consumption and cancer of the prostate and between mean age at first birth, gross internal product and milk consumption and cancer of the breast. Cancer of the ovary was positively correlated with mean age at the first birth, and negatively with average number of births. Among the unexpected correlations observed, the most remarkable ones were the strong positive coefficient between skin cancer mortality and latitude (which can however be explained in terms of different constitutional characteristics of skin color in various Italian regions), and the pattern of coefficients emerging for gastric cancer, showing positive correlations with gross internal product or meat and negative ones with bread, pasta or fish. These and other results (including the analysis of several first-order partial correlation coefficients) are discussed with regard to their limitations and major points of interest, and in comparison with similar studies conducted on different populations.

Adult↗
PubMed2002

A survey of agents associated with neonatal diarrhea in Iowa swine including Clostridium difficile and porcine reproductive and respiratory syndrome virus.

This survey was undertaken to determine the relative frequency of agents that are currently associated with neonatal diarrhea in swine, including Clostridium difficile and porcine reproductive and respiratory syndrome virus (PRRSV). The subjects for this study were the first 100 live 1-7-day-old piglets submitted to the Iowa State University Veterinary Diagnostic Laboratory with a clinical signalment of diarrhea, beginning on January 1, 2000. The evaluation of each pig included bacterial culture of a section of ileum, 2 sections of jejunum, and a single section of colon; a fluorescent antibody test (FAT) or immunohistochemistry (IHC) for transmissible gastroenteritis virus (TGEV); ELISA's for rotavirus and C. difficile toxins; IHC for PRRSV; and microscopic examination of ileum, midjejunum, spiral colon, liver, spleen, and lung. Survey results demonstrate a decline in the relative number of diagnoses of TGEV, Escherichia coli, and Clostridium perfringens type C compared with retrospective data. The combined case frequency rate for these 3 pathogens dropped from 70% in 1988 to 21% in 2000. This survey also demonstrated the emergence of C. difficile as an important pathogen of neonatal swine. Clostridium difficle toxin was detected in the colon contents of 29% of the piglets, and at least 1 toxin-positive animal was identified in 55% of the cases. All 29 C. difficile toxin-positive piglets had mesocolonic edema, and colitis was observed in 21 of 29 toxin-positive animals. PRRSV-positive macrophages were detected in the lamina propria of intestinal villi by IHC in 10 piglets with diarrhea. In 6 of these cases, PRRSV was the only pathogen detected. Gross and microscopic lung lesions were not a reliable indicator of PRRSV infection in these neonatal pigs with diarrhea. The addition of tests for C. difficile and PRRSV to a routine neonatal diarrhea diagnostic protocol resulted in a significant increase in thediagnostic success rate on both individual animal and case bases.

Animals↗
PubMed2004

Obstetric fistula: the challenge to human rights.

Obstetric fistula can be explained to result from different causes. These holes in the tissue wall between the vagina and bladder and/or rectum are most prevalent in resource-poor countries, attributable to prolonged obstructed labour and absent or inaccessible remedial prenatal services. Obstructed labour is often due to small pelvic size, resulting from women's youth and premature childbearing and/or malnutrition. Poverty at national health-service and family levels often predisposes pregnant populations to suffer high rates of fistula. Global estimates showing up to 100,000 new cases each year and 2 million affected girls and women are probably gross underestimates. Fistula devastates lives of sufferers, who are often expelled by husbands and become isolated from their families and communities. Failures of states to provide prenatal preventive care (including medically indicated cesarean deliveries) and timely fistula repair violate women's internationally recognized human rights, especially to healthcare in general and reproductive healthcare in particular.

Developing Countries↗
PubMed1976

[The influence of the N-mustard derivative "cytostasan" on pregnancy and fetal development in the rat].

This presentation describes the action of Cytostasan, a nitrogen mustard compound of benzimidazole, on reproduction and embryonic development of Wistar rats. Single doses from 20 through 100 mg/kg body weight were given intraperitoneally on the 4th, 7th, 9th, 11th or 13th day post coitum. All test animals were sacrificed on the 20th day of pregnancy. The following parameters served as a base for evaluation: the means of implantation rates, resorption rates, fetal body weights and the number of dead and living fetuses. Malformations were detected by outer inspection for gross anomalies, by means of the razor blade technique for malformations of organs and by alizarin preparations for detecting anomalies of the osseuos skeleton. All results were compared with those of an untreated control group and evaluated by statistical means. Cytostasan exerts embryotoxic and teratogenic effects in appropriate dosage. Notwithstanding the fact of giving high doses (1/2 LD 50) there is no loss of blastocysts before implantation: the number of implantation sites equals that of the control group. The resorption rate increases at all examined days of development after application of 40 mg/kg, but 20 mg/kg exert effects only on days 4, 7, and 11 p. c. There is no action on the number of living fetuses after injection of 20 mg Cytostasan/kg body weight. After application of 40 mg/kg the number of living fetuses decreases especially on the 7th, 9th, and 13th day p. c. There is a dose-dependent stunting: the fetal body weight is not reduced after a dosage of 20 mg/kg, but 40 mg/kg cause a considerable loss of weight during embryogenesis (days 9, 11, 13). It is impossible to induce stunting during blastogenesis (days 4 and 7). The observed patterns of malformation are relatively uniform: kinked tails, omphaloceles, hydronephroses, hydrocephali. Skeletal defects are absent. The results received are compared with other findings on aklylating antitumour drugs.

Abnormalities, Drug-Induced↗
PubMed2006

Two distinct groups of natural populations of Fagopyrum urophyllum (Bur. et Franch.) Gross revealed by the nucleotide sequence of a noncoding region in chloroplast DNA.

Fagopyrum urophyllum is a cross-pollinating perennial woody shrub species belonging to the urophyllum group of Fagopyrum. Natural populations of F. urophyllum were morphologically classified into two distinct groups, the Dali group and the Kunming group without exception. This grouping was verified by molecular phylogeny based on the nucleotide sequence of chloroplast DNA. The reproductive isolation found between the two groups was almost perfect as the distribution of two groups did not overlap each other. The net nucleotide substitution rate (Da) between the two groups was at the same level as between two distinct species. These data suggests that the two groups should be classified into distinct species if future studies on F. urophyllum confirm complete reproductive isolation and no ambiguously classified populations in the border area of the central Yunnan province of China.

DNA, Chloroplast↗
PubMed2004

Effects of mercury on the life table demography of the rotifer Brachionus calyciflorus Pallas (Rotifera).

Mercury is highly toxic to a variety of aquatic organisms including zooplankton. The functioning of freshwater ecosystems can be altered if rotifers, being a natural food link between phytoplankton and fish larvae, are contaminated by mercuric compounds. In order to detect age-specific responses of the rotifer Brachionus calyciflorus to mercury toxicity (5 nominal concentrations as chloride viz. 0, 0.000625, 0.00125, 0.0025 and 0.005 mg l(-1)), we used the standard life table method at two different food (Chlorella vulgaris) levels (0.5 x 10(6) and 1.5 x 10(6) cells ml(-1)). Data indicated that increase in mercury concentration had an increasingly intense negative effect on many of the life history variables, while at higher food levels, its impact was less. A nearly rectangular survivorship pattern was obtained in controls, especially at higher food levels. This trend gradually changed to a steep fall as the concentration of the heavy metal in the medium increased from 0 to 0.005 mg l(-1). At any given food density, increase in the mercury concentration resulted in decreased age-specific reproduction. A maximum of 3.5 offspring female(-1) was observed in controls at higher food density. The average lifespan varied from 6 to 8 days at low food level, depending on the heavy metal concentration in the medium. The corresponding values at high food level varied from 8 to 12 days. Regardless of mercury concentration in the medium, gross and net reproductive values varied from 10 to 33 and 4 to 19 offspring female(-1). The longest generation time (about 9 days) of B. calyciflorus was obtained at 1.5 x 10(6) cells ml(-1) food density in control, while the shortest was 5 days at low food level and high (0.005 mg l(-1)) mercury concentration in the medium. Depending on the food level and heavy metal concentration in the medium, the rate of population growth (r) varied from 0.32 to 0.62 d(-1). In general, higher food level resulted in higher r. Except generation time, all other derived variables were significantly influenced by food level and the heavy metal concentration in the medium.

Analysis of Variance↗
PubMed2005

Evaluation of gross anatomical features of cervix of tropical sheep using cervical silicone moulds.

The lambing rate obtained following cervical artificial insemination (AI) with frozen semen in sheep is low mainly due to the inability of frozen-thawed sperm to traverse the tortuous nature of the cervical canal. Although acceptable fertility has been attained by circumventing the cervical barrier through laparoscope aided intrauterine AI, the emphasis is currently given on the development of alternate non-invasive transcervical AI procedures. The complex anatomy of the cervix does not facilitate easy transcervical passage for an insemination catheter. The aim of the present study was: (i) to examine the gross anatomy of the cervix in slaughtered ewe lambs and adult ewes of the native Malpura and Kheri breeds raised under semi-arid tropical environment; and (ii) to cast silicone moulds of the reproductive tracts for measuring the dimensions of the cervix. Eighty reproductive tracts were excised immediately from carcass of Malpura and Kheri ewes and the external os of each one was classified depending on their appearance as duckbill, spiral, rosette or flap. The cervical canal of each tract was filled with a silicone sealant for casting the mould. Fifty complete silicone moulds were obtained representing 25 from ewe lambs and 25 from adult ewes. The mean lengths of the cervical mould of ewe lambs and adult ewes were 3.8+/-0.12 and 5.3+/-0.15 cm, respectively. The average number of funnel shaped folds in the cervical mould of ewe lambs and adult ewes were 3.2+/-0.19 and 3.4+/-0.22. However, the second and third-folds from the os were observed to be accentric in both ewe lambs and adult ewes. The information generated in this study would be useful for increasing the success rate of penetration in ewes exhibiting estrus in order to improve the lambing rate of tropical ewes following transcervical AI.

Aging↗
PubMed1997

Seasonal courses of CO(2) exchange and carbon balance in fruits of Cinnamomum camphora.

Carbon dioxide exchange in fruits of Cinnamomum camphora Sieb. was followed over a growing season from July to December 1992. Dark respiration was exponentially related to temperature, with a Q(10) value near 2. Light dependence of photosynthetic CO(2) refixation, i.e., the ratio of gross photosynthesis to dark respiration, was approximated by a hyperbolic function. Seasonal variation in maximum CO(2) refixation capacity ranged between 52 and 174%, reaching a maximum in early August. Daily photosynthetic CO(2) refixation ranged between 17 and 51% over the growth period. We evaluated seasonal variation in translocation rate to the fruit on the basis of the seasonal rates of gross photosynthesis, dark respiration and increase in fruit dry weight, and used the results to develop a simple carbon flow model of fruit development. Seasonal changes in translocation rate paralleled those in fruit growth rate, with two peaks during the periods before and after September. Seed formation took place in the period between the two peaks. The relationship between fruit growth rate and translocation rate was approximated by a linear function. The carbon flow model estimated that, over the reproductive period, the amount of assimilate translocated to each fruit was 377.2 mg dry weight, of which 58.5% was accounted for by weight growth and 41.5% was consumed by net respiration. Carbon dioxide refixation accounted for 22.9% of the carbon balance of the fruit.

Journal Article↗
PubMed1986

Reproductive and teratological effects of continuous low-level dietary T-2 toxin in female CD-1 mice for two generations.

A two-generation female reproduction and teratology study was undertaking using 0, 1.5 and 3.0 ppm of T-2 toxin in a semisynthetic diet. Conception rate was lowest at the first breeding and lowest in the control group at this time, but in later breedings the conception rates of each group were very similar. No significant differences were noted in litter size, death of fetuses, sex of fetuses and gestational length. Feed consumption was similar in all groups, as were the non-pregnant or pregnant female weight gains. Although the second-generation offspring grew faster than the first-generation offspring, and significantly lower body weights were seen in the 3.0 ppm T-2 toxin group at 2, 5 and 6 weeks of age, all offspring reached the normal weight for CD-1 mice at 6 weeks of age. Gross and histological evaluation of all animals at post-mortem examination did not reveal any significant results, nor were there significant differences in major and minor or retardation defects among the treatment groups. Relative spleen weights of the second-generation offspring were significantly higher in control females compared with the treated groups but treated males had significantly increased relative spleen weights compared with control males of this generation. It was concluded that no long-term reproductive and teratological effects of low-dose dietary T-2 toxin were found in this study.

Abnormalities, Drug-Induced↗
PubMed2002

Seasonality of births and conceptions in a pastoral community of the province of l'Aquila (Abruzzo, Italy), 1802-1965.

Natality rates and seasonality of births and conceptions were analyzed from 6,116 birth records in the pastoral community of Roio (Abruzzo, Italy) from 1802 to 1965. Gross natality rates averaged 25.5 x 1000 in the past, lower than those reported for agricultural groups. Seasonality of births showed a marked pattern: 807-67% of births occurred in the first six months of the year. The monthly distribution of conceptions was compared to that of marriages. The results show a high correlation in the 19th century and a lower one in the 20th century. These findings suggest that pastoralism acted as a primary regulator of reproduction in this community.

Birth Rate↗
PubMed1990

Effects of treadmill exercise on the distribution of blood flow between the hindlimb muscles and abdominal viscera of the laying fowl.

1. Blood flow distribution between the abdominal viscera and the leg muscles of regularly-laying Rhode Island Red hens was measured at rest and immediately following treadmill exercise, using the radioactive microsphere technique. 2. Exercise brought about a 150% increase in metabolic rate and this was maintained continuously for 90 min. 3. Although there was a small shift in blood flow distribution towards the hindlimb muscles at the expense of the kidneys and reproductive organs, this was not statistically significant. 4. There was a significant reduction in blood flow to the preovulatory follicles of the ovary during exercise, relative to the rest of the abdominal viscera. 5. It is concluded that exercise of this intensity is insufficient to bring about gross changes in blood flow distribution between the abdominal viscera and the hindlimb muscles. The implications of this finding are discussed in relation to the nutrient and blood flow requirements of the reproductive organs.

Animals↗
PubMed1989

Control of induced infestations of three African multihost tick species with sustained-release ivermectin.

The efficacy of ivermectin, released intraruminally from a 28-day-delivery device was evaluated in two titration studies against induced infestations of adult Rhipicephalus appendiculatus, R. evertsi and Hyalomma truncatum on cattle. Cattle were given a sufficient number of devices to release ivermectin at approximately 20, 40, 60 or 80 micrograms kg-1 day-1 at a steady-state rate 7-28 days after administration. Tick mortality was recorded, engorged female ticks were weighed and individually incubated, and reproductive data were recorded to determine a reproductive index for the species at various dose levels. Mortality of male and female ticks compared to that of controls was directly related to the daily dose of ivermectin, as was the number of ticks not engorging. Ticks fed on ivermectin-treated cattle had a smaller mass when engorged and laid smaller egg-masses, both absolutely and as a proportion of engorged mass. The index of reproduction of R. appendiculatus was reduced by more than 99.9% at 20 micrograms kg-1 day-1, and the reproductive indices of R. evertsi and H. truncatum were reduced by more than 99.9% at dose rates of 40 micrograms kg-1 day-1 and above. Practical implications of the application of sustained-release ivermectin for the control of multihost ticks and tick-borne diseases are discussed.

Animals↗
PubMed2004

Morbidity effects on productivity and profitability of stocker cattle grazing in the Southern Plains.

Effects of bovine respiratory disease (BRD) on stocker cattle systems are unknown under extensive rangeland environments. Three experiments were conducted to test the hypothesis that BRD-based morbidity is a major factor affecting the productivity and profitability of stocker cattle grazing Southern Plains rangelands. In Exp. 1 (658 male calves; average BW = 231 kg), 17% of the cattle were treated for BRD <8 d, 6% for 8 to 14 d, and 8% for >14 d. Morbid cattle had lower ADG than did healthy cattle (P < 0.10). Cattle requiring 14 d of pharmaceutical therapy gained less than cattle having <14 d therapy (P < 0.01). In Exp. 2, (279 steers and bulls; average BW = 216 kg), the ADG by steers (0.74 kg x animal(-1) x d(-1)) was greater (P < 0.05) than by bulls castrated after arrival (0.64 kg x animal(-1) x d(-1)). Castration after arrival led to a 13.5% loss in daily gain and a 10.3% loss in season-long gain. More (P < 0.05) bulls castrated after arrival (60%) were morbid compared with steers (28%). In Exp. 3, 633 heifers (average BW = 251 kg) were used to test the effects of morbidity on weight gain and reproduction. Heifers with lower initial weights exhibited increased (P < 0.05) morbidity. Heifers requiring two or more antibiotic treatments gained 0.03 kg/d less (P < 0.10) than did healthy heifers and had lower (P < 0.05) conception rates (66 vs. 81%). Conception rate in twice-treated heifers was 19% less than healthy heifers. Morbid heifers conceived 0.6 mo later (P < 0.05) than healthy heifers. Under the conditions of Exp. 1 and Exp. 2, morbidity decreased net returns 9.7 to 21.3% per animal. Adjusted gross returns per animal in Exp. 3 for replacement heifers were 3 to 7.8% less for morbid heifers.

Animal Husbandry↗
PubMed1988

Bluetongue in free-ranging pronghorn antelope (Antilocapra americana) in Wyoming: 1976 and 1984.

At least 3,200 pronghorn (Antilocapra americana) died during a bluetongue (BT) epizootic in eastern Wyoming during late September and early October 1976. In August and September 1984, another BT epizootic occurred in northeastern Wyoming resulting in 300 known pronghorn deaths. In 17 pronghorn examined postmortem, hemorrhages and edema were the most common gross pathologic changes. Microscopic changes included hemorrhage, edema, arterial fibrinoid necrosis, lymphoid depletion in splenic and lymphatic follicles, and neuronal necrosis. Bluetongue virus serotype 17 was isolated from pronghorn in both epizootics. Mortalities ceased with the advent of cool weather in late September and October. Seventy-six of 94 pronghorn killed by hunters during the latter period of the 1976 epizootic, and 14 of 24 pronghorn killed 1 yr later had serologic evidence of exposure to BT virus. The reproductive rate in pronghorn was depressed to 47 fawns per 100 does in August 1977, but returned to 93 fawns per 100 does by 1978. Following the 1984 outbreak, the reproductive rate was similarly depressed, but the cause was confounded by other environmental and range conditions. Deer, mostly mule deer (Odocoileus hemionus), also died during both epizootics of what was presumed to be BT.

Animals↗
PubMed2005

Effects of 6-mercaptopurine treatment on sperm production and reproductive performance: a study in male mice.

OBJECTIVE: Azathioprine and 6-mercaptopurine interact in purine metabolism and DNA synthesis, thus their potential mutagenic effects have been of concern in the management of inflammatory bowel disease (IBD), especially in patients of childbearing age. Although several clinical studies have indicated their safety in both reproduction and pregnancy, in a recent large epidemiological study concerns were raised about their adverse effects in pregnant patients with IBD, and experimental or basic data on this subject are limited. The aim of this study was to investigate sperm production, sperm quality, and reproductive outcome following prolonged 6-MP administration to male mice. MATERIAL AND METHODS: Highly inbred Balb/c adult male mice were used. 6-MP at doses of 2, 5, and 8 mg/kg (n = 9 for each group) was given daily for 51 days and the treatment group was compared with controls. After 45 days of treatment, the mice were mated with females. Following 13 days of pregnancy, the products of conception were evaluated and live fetuses were examined for gross malformations. Sperm production and morphology were examined after 51 days of 6-MP administration. RESULTS: Treatment with 6-MP at all doses did not affect sperm morphology and sperm production in the testicular tubules, as compared with controls (70% normal sperm). However, pregnancy rates were inversely related to escalating doses of 6-MP: 55%, 41%, 28%, and 16% for control, 2, 5, and 8 mg/kg groups, respectively. Resorption rates (abortions) were 21% in the control group as compared with 45-50% in all the treatment groups, but the incidence of major congenital malformations was not increased. CONCLUSIONS: Long-term 6-MP treatment in male mice did not impair sperm production and sperm morphology. However, a significantly high rate of embryonic resorption indicated occult sperm damage. Thus, normal sperm analysis does not necessarily imply that sperm damage at genetic level did not occur. It is difficult to extrapolate from these results to the clinical use of 6-MP/azathioprine in IBD patients; however, further basic genetic testing for DNA damage and clinical follow-up are warranted.

Animals↗
PubMed1991

Reproductive toxicity and toxicokinetics of 2,3,7,8-tetrachlorodibenzo-p-dioxin. 2. Problem of paternally-mediated abnormalities in the progeny of rat.

Possible effects on the next generation after long-term exposure (subcutaneous administration) of male rats to very high doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were studied. Two dose regimes were applied: TCDD-25 (initial dose: 25 micrograms/kg body wt; maintenance dose: 5 micrograms/kg body wt, once weekly) and TCDD-75 (initial dose: 75 micrograms/kg body wt; maintenance dose: 15 micrograms/kg body wt). Male rats were treated for 10 weeks before mating and then throughout the entire 12 week mating period. They were mated to unexposed virgin females. One group of pregnant females was used for teratological evaluations, and another group was allowed to deliver. No significant differences were observed in the number of implantations or fetuses per litter, and resorption rate, and fetal weight between the controls and TCDD-treated groups. No gross-structural anomalies occurred in any of the fetuses sired by TCDD-treated males. In the TCDD-25 group an increased frequency of two types of variations was observed which also occur in controls: incompletely ossified fingers (TCDD-25 = 5.1%, controls = 2.6%), and incompletely ossified ossa zygomatica (TCDD-25 = 1.8%, controls = 0.5%). In the TCDD-25 group a slight but statistically significant increase was observed in the rate of stillbirths (TCDD-25 = 1.3%, controls = 0.1%), apparently due to an unusually low frequency occurring in the controls (overall historical controls = 0.6%). There was no difference in postnatal mortality (TCDD-25 = 1.3%, controls = 1.3%). Taken together, despite the very high doses of TCDD used, the data do not provide evidence for biologically significant paternally-mediated developmental toxicity in the fetuses and newborn.

Abnormalities, Drug-Induced↗