• Journal of Animal Science and Technology
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• v.62 no.2
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• pp.218-226
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• 2020

The present study investigated the effects of loose farrowing type during gestation and after farrowing on reproductive performance and of lactating sows. A total of 22 primiparous sows (Landrace; average initial body weights [BW], 228.54 ± 12.79 kg) were allotted to one of two treatments on the basis of body weight. Sows were divided into two experimental groups, conventional farrowing crates (CON), and loosed-farrowing pens (LFP). The experiment duration was around 38 days ranging from 10 days before parturition to 28 days after parturition. Gestating sows at the age of 105 d were placed in gestational stalls (group housing). All the sows were fed a common diet according to the National Research Council requirements for lactation. Cross-fostering was performed within 1 day of parturition. From 1 day after weaning, estrus detection was performed twice-daily (0900 and 1730 h) for 10 min by boar exposure. There were significant effects of LFP housing type on the farrowing duration, and farrowing interval. At the farrowing time, none of the litter parameters including total born, stillborn, mummy, born alive piglets and total litter weight and piglet weight were affected. There were no effects of housing type on the mortality of piglets at d 1, 3, 7, 21, and 28. In conclusion, the result of this study showed that there is no performance difference between the crated or LFP sows, which indicate that the LFP housing has the potential to be used as an alternative to the crated house without any detrimental effects in reproduction performance of lactating sows.

• Journal of Medicine and Life Science
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• v.16 no.1
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• pp.34-38
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• 2019

Hypogonadism is a clinical syndrome that results in hormone deficiency and can be classified as 1) primary caused by the gonadal failure and 2) secondary by the hypothalamus-pituitary gland dysfunction and/or cardiometabolic complications. Recently the presence of thyroid hormone receptors in different testicular cell types was demonstrated, and thus thyroid dysfunctions would be another cause of secondary hypogonadism. Thus, we investigated the effects of perinatal hypothyroidism on hypogonadism in male Sprague-Dawley rats. Perinatal hypothyroidism was induced by daily administration of 0.05% 6-propyl-2-thiouracil (PTU) by tap water from gestation day 15, which were compared with negative control (PTU (-)) group. At postnatal day 28, hypothyroid pups were divided into 2 groups: PTU (+) group - continued PTU treatment and PTU (+/-) group - stopped PTU until postnatal day 49. Body weights, dehydrotesosterone (DHT), and testosterone levels were checked 2 and 3 weeks after grouping. Body weights were significantly decreased in PTU(+) and PTU(+/-) groups compared with PTU (-) group at postnatal day 28. 3 weeks later, PTU (+/-) group significantly gained weight compared with PTU (+) group. DHT and testosterone levels significantly decreased with PTU treatment, but increased 3 weeks after stopping PTU administration. Perinatal PTU-induced hypothyroid hypogonadism was sustained for 2 weeks after stopping PTU administration, but restored gonadal hormone levels 3 weeks after stopping PTU. These results suggest that researchers should design an experiment on hypothyroid hypogonadism based on the estimated period.

• Biomolecules & Therapeutics
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• v.3 no.1
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• pp.38-46
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• 1995

DA-125, a new anthracycline antitumor antibiotic, was administered at dose levels of 0, 0.04, 0.2 and 1.0 mg/kg/day intravenously to pregnant and subsequently delivered Sprague-Dawley rats from day 17 of gestation to day 21 of lactation. Effects of test agent on general toxicity of dams and growth, behaviour and mating performance of F1 offspring were examined. At 1 mg/kg, one out of the twentytwo dams showed difficult delivery, characterized by a stillbirth. Reduction in body weight, loss in food intake, and decrease in spleen weight were also observed in dams. In addition, the lower rates of successful performances in memory test (28.6%) and necrosis of tail end (9.5%) were seen in F1 offspring. At 0.04 and 0.2 mg/kg, no toxic effect on dams and F1 offspring was observed. There were no malformed Fl and F2 fetuses in all groups. The results indicate that the no effect dose levels(NOELs) of DA-125 are 0.2 mg/kg/day for dams and Fl offspring, and over 1 mg/kg/day for F2 fetuses.

• Toxicological Research
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• v.19 no.2
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• pp.123-131
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• 2003

This study was carried out to assess the combined repeated dose, reproduction and developmental toxicities of benzoyl peroxide for OECD SIDS (Screening Information Data Set) program. Male and female Sprague-Dawley rats were exposed to benzoyl peroxide at dose levels of 0, 250, 500 and 1,000 mg/kg/day for 29 days for males and for 41-51 days for females. No deaths were found in all animals including control group during exposure period. No hematological effects attributable to benzoyl peroxide were observed in all treated groups. Significant decrease in the weight of testes and epididymis were observed in males at 1,000 mg/kg/day. In females at 1,000 mg/kg/day, slight histopathological effects in uterus such as epithelial vacuolation or hyperplasia were observed. No treatment-related changes in precoital time and rate of copulation, fertility and gestation period were noted in all treated groups. There was no evidence of teratogenic effect of benzoyl peroxide, but body weight of pups at 1,000 mg/kg/day was significantly decreased. NOAEL for combined repeated dose and reproduction/developmental toxicity was 500 mg/kg/day.

• Environmental Mutagens and Carcinogens
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• v.22 no.2
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• pp.125-132
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• 2002

To evaluate the modifying effect of Kwao Kreu, Pueraria mirifica (PM) well-known as a rejuvenating folk medicine from Thailand, peri- and post-natal studies were carried out in rats. PM extract was administered to pregnant Sprague Dawley (SD) rats by oral gavage from gestation 6 (GD 6) to postnatal day 21 (PND 21). The amount of administered in this study was 0.042, 0.42 and 4.2 mg/kg/day, respectively. There were no treatment related changes of dams in deaths, clinical signs, and parturition. Treatment related changes in body weight, food consumption and lactation of dams were not observed. F1 fetuses in external abnormality, physical development, reflex/sensory functions and behavioral development were not found. No adults and F1 fetuses in organ weight was found with the exception of vagina and uterus of F1 fetuses. The results showed that PM extract, up to 4.2 mg, had no adverse effects on the peri- and post-natal development of rats. Therefore, PM extract has no adverse effects on peri- and post-natal development of rats.

• Biomolecules & Therapeutics
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• v.2 no.1
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• pp.94-101
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• 1994

DA-125, a new anthracycline antitumor antibiotic, was at dose levels of 0, 0.03, 0.1 and 0.3 mg/kg/day administered intravenously to Sprague-Dawley male rats from premating to mating period and to females from premating to early gestation period. Effects of test agent on general findings and reproductive performance of parent animals and embryonic development were examined. No treatment-related changes in clinical signs, body weight, food consumption and necropsy findings were observed in all groups of both sexes. At 0.3 mg/kg, a decrease in the weight of spleen was found only in male rats. Mating performance and fertility of parent animals were not adversely affected by all doses tested. Fl fetuses showed no changes related to treatment of DA-125, except that at 0.3 mg/kg, an increase in the resorption rate was seen. The results show that the no effect dose levels (NOELS) for general toxicity of parent animals and fetal development are 0.1 mg/kg/day and NOELS for reproductive capability are over 0.3 mg/kg/day.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.339-348
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• 1996

A new composite antibiotic, SM-101 (sulbactam·metampicillin), was at dose levels of 0, 250, 500 and 1000 mg/kg/day administered intravenously to pregnant and subsequently delivered Sprague-Dawley rats from day 17 of gestation to day 21 of lactation. Effects of test agent on dams and growth, behaviour and mating performance of Fl offspring were examined. In dams, one death occurred at 1000 mg/kg. The increase in kidney weight of the 250, 500 and 1000 mg/kg group was found. In F1 offspring, both delayed incisors eruption and decreased body weight were observed in females of the 1000 mg/kg group. The increase in the weights of liver and kidney was found in males of the 1000 mg/kg group. No treatment-related abnormalities were observed in each treated group in terms of behaviour and reproductive performance. In F1/F2 fetuses, no drug-induced abnormalities occurred at all doses tested. The results show that the no effect dose level (NOEL) of SM-101 is under 250 mg/kg/day for dams and 500 mg/kg/day for F1 offspring, and over 1000 mg/kg/day for F1/F2 fetuses.

• Development and Reproduction
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• v.8 no.2
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• pp.85-89
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• 2004

This study is illustrated that 1) the effects of DEHP administration on body weight, sex ratio and litter size on 19 days in the prenatal period 2) the effects of reproductive organ weight and blood hematological values on 25 days postpartum in pregnant mice. DEHP was administrated to pregnant mice by intraperitoneal injection at 0, 0.5, 1.0 and 10.0mg/kg B.W from day 1 to day 16 in the gestation period with 5 times at 3 days interval. There were no significantly differences in the material body weight, litter size and sex ratio on 19 days in the prenatal period. The body weight of the fatal male mice was slightly lower in 1.0 and 10.0mg DEHP groups than in any other groups. The reproductive organ weight and hematological values in dam mice on 25 days postpartum were not affected by DEHP administration. The histological evaluation of ovary in dam mice on 25 days after dilivery was not different in all experimental groups, but the endometriosis and edema of uterus in dam mice were significantly decreased in 0.5mg DEHP group than that of control group.These results indicate that the administration of low concentration of DEHP was not affected on reproductive characteristic and blood hematological values in pregnant mice.

• The korean journal of orthodontics
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• v.31 no.6 s.89
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• pp.579-587
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• 2001

Cleft palate has been studied with epidemiologic and molecular methods, and many etiologic factors have been examined closely Among the research methods, biologic molecule research has been the most important method for cleft palate formation study The $TGF-\beta$ played an important role in cell migration, epithelial-mesenchymal transdifferentiation, extracellular matrix synthesis and deposition. But there was not much research on the correlation cleft palate induced by beta-aminonitroproprionitrile(BAPN) and $TGF-\beta$ expression. The purpose of the present study was to examine how $TGF-\beta$ is expressed in cleft palate rats. 4 Timed-pregnant Sprague-Dawley rats were obtained on the 10th gestation day. On the 13th day of gestation, BAPN-monofumarate salts (${(C_3H_6N_2)}_2{\cdot}C_4H_4O_4$) were individually, ovally administered to 3 pregnant rats at a ratio of 1g/kg body weight. And 4 pregnant rats were sacrificed on day 20 post coitus (p.c.). The $TGF-\beta$ expression in the cleft formed rats fetuses showed the following patterns : 1. Osteoblast and mesenchymal cells of the cleft pa)ate rats were of low expression compared with those of the control rats. 2. The cleft palate rats didn't show uy difference in the $TGF-\beta$ expression of osteocyte item the control rats. 3. In western blot analysis, the thickness of band of $TGF-\beta$ in the cleft palate rats was thinner and more diluted than that of the control rats.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.185-187
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• 2004

The co-administration of BPA and BBP induced slow weight gain compared with single administration in dams. Also, such mixture induced low neonatal body weights in next generation. The dams treated with BPA and BBP showed significant organ weight changes in liver, spleen exposed during lactational periods. But the dams exposed during lactational periods showed significant organ weight changes not only in liver, spleen but also in kidney, uterus and ovary. The F1 female rats exposed during lactation periods showed significant organ weight changes in liver, spleen, ovary. The F1 male rats showed significant organ weight changes in liver, kidney, epididymis, vesicular glands, prostate. However no clear synergistic effects of BPA and BBP could be found. Estrogen receptor ${\alpha}$ expression by BPA and BBP in the uterus(dam, F1 female) and testis(F1 male) were studied. There was no significant different $ER{\alpha}$ expression pattern between control and treated groups. But $ER{\alpha}$ expression were increased in F1 male testis and female uterus. F1 male showed distinct $ER{\alpha}$ expression, especially in the group of lactational combined exposure. Synergistic $ER{\alpha}$ expression was found by combined treatment of BPA and BBP.