腹腔注射N-甲基-D-天冬氨酸对母鼠发情率、早期胚胎及胚子数的影响

为研究腹腔注射N-甲基-D-天冬氨酸(NMDA)对母鼠发情率和早期胚胎及胚子数的影响,试验选取40只昆明小鼠[(26±1.37)g],随机分为对照组和试验组(每组各20只),对照组腹腔注射0.2mL生理盐水,试验组腹腔注射0.2mLNMDA溶液,采用棉签蘸取母鼠阴道黏液,涂片后用苏木精(HE)染色,判定母鼠发情情况。随后在发情母鼠与公鼠合笼后第3天,每组随机取10只颈椎脱臼法处死小鼠,冲胚后在体视镜下捡胚观察胚胎个数;第9天处死剩余小鼠,取出子宫统计胚子数。试验结果显示,腹腔注射NMDA试验组母鼠发情率、胚胎数和胚子数分别比对照组提高28.57%、18.18%和12.94%。该试验表明腹腔注射NMDA可促进母鼠的发情,提高早期胚胎和胚子数,为NMDA在动物繁殖中的应用提供了理论基础。     

醋酸铅对妊娠小鼠雄性后代生殖毒性的研究

将妊娠母鼠随机分为高剂量(1／10LD50)、中剂量(1／50 LD50)、低剂量(1／250LD50)和溶剂对照组。高、中、低剂量染毒组和对照组母鼠分别于妊娠的9,11,13,15 d和17 d腹腔注射1.2,0.24,0.048 g／L的醋酸铅[Pb(CH3COO)2·3H20]溶液和灭茼蒸馏水0.01 mL／g。研究醋酸铅对妊娠小鼠雄性后代的生长发育和生殖能力的影响。试验结果表明:①高剂量染毒母鼠带仔行为受到醋酸铅的显著影响;②各试验组后代公鼠体重增长变化无统计学差异(P>0.05);③各试验组公鼠的睾丸、附睾湿重及其与体重的比值均无明显差异(P>0.05);④各染毒组后代公鼠精子相对密度显著低于对照组(P<0.01);⑤各染毒组后代公鼠精子活力与对照组之间无统计学差异(P>0.05);⑥高剂量和中剂量组后代公鼠精子畸形比率显著高于对照组(P<0.05),低剂量组则与对照组无统计学差异(P>0.05);⑦备染毒组后代公鼠精子顶体形态异常率与对照组之间无统计学差异(P>0.05)。     

PCV2对昆明母鼠产仔及其仔鼠生长状况的影响

为了研究PCV2对母鼠产仔及仔鼠生长状况的影响,试验取4只SPF级公鼠和12只SPF级母鼠进行腹腔接种PCV240.2mL,另取2只SPF公鼠和6只SPF母鼠腹腔接种无菌细胞培养液0.2mL作为对照组.接种10天后,试验组和对照组的公鼠和母鼠均合笼饲养,待母鼠生产后记录窝产仔数、死胎数、弱仔数、断奶数,并统计断奶仔鼠的...     

醋酸铅对母鼠生殖与胚胎发育影响

将420只体质量为(15.32±2.01)g的雌性昆明系小鼠随机分为5个处理组和1个对照组,每组设7个重复,每个重复10只。各处理组分别腹腔按体质量注射10、15、20、25、30mg/kg的醋酸铅溶液,对照组注射等体积的灭菌生理盐水,每隔2d注射并称重1次,共注射10次,期间记录小鼠体质量及临床表现。当小鼠体质量达到25g以上时,分批对各试验组和对照组进行超排处理,腹腔注射10IU马绒毛膜促性腺激素(PMSG),47h后注射10IU人绒毛膜促性腺激素(hCG),并与公鼠合笼。合笼后87~96h内颈椎脱臼处死小鼠,观察卵巢、子宫形态,并统计胚胎数,同时制作卵巢、子宫石蜡切片,观察其病理组织学变化,研究醋酸铅对雌性小鼠卵巢、子宫组织结构及早期胚胎发育的影响。结果显示:(1)当醋酸铅染毒剂量≥20mg/kg时,可明显抑制小鼠体质量的增长,随着染毒剂量的增加,作用时间的延长,小鼠体质量增加明显趋缓,与对照组相比,差异显著或极显著(P0.05,P0.01);(2)染铅组母鼠早期胚胎发育受到显著影响,主要表现为回收胚胎总数以及受精卵发育到桑椹胚和囊胚的总数均显著低于对照组(P0.05),而各染铅组退化胚、延迟胚数和未受精卵总数显著高于对照组(P0.05);(3)染铅组卵巢中的初级卵泡、次级卵泡、成熟卵泡数量明显低于对照组,而原始卵泡、闭锁卵泡数量明显高于对照组。(4)染铅组小鼠卵巢和子宫形态发生明显畸形,当醋酸铅染毒剂量≥20mg/kg时,与对照组相比,差异显著或极显著(P0.05,P0.01)。且上述变化均呈明显的剂量一时间效应。研究结果表明,当醋酸铅暴露剂量≥20mg/kg时,可对小鼠生长发育具有明显抑制作用,同时使母鼠生殖器官卵巢和子宫的结构造成严重损害,并影响其生殖功能与早期胚胎发育。     

醋酸铅对妊娠小鼠雌性后代受精和胚胎发育毒性研究

将妊娠小鼠随机分为高剂量 (1 / 1 0LD50 )、中剂量 (1 / 50LD50 )、低剂量 (1 / 2 50LD50 )和溶剂对照组。高、中、低剂量染毒组和对照组小鼠分别于妊娠的 9,1 1 ,1 3,1 5d和 1 7d腹腔注射 1 .2 g/mL ,0 .2 4g/mL和 0 .0 48g/mL的醋酸铅 [Pb(CH3COO) 2 ·3H2 O]溶液和灭菌蒸馏水 ,注射量 0 .0 1mL/ g。研究醋酸铅对染毒妊娠小鼠雌性后代生长发育和卵母细胞受精、受精卵卵裂及早期胚胎发育的影响。试验结果表明 :①各组后代母鼠断奶后体重变化规律类似 ,试验结束时各组小鼠平均体重无统计学差异(P >0 .0 5) ;②各染毒组后代母鼠受精卵比率极显著低于对照组 (P <0 .0 1 ) ;③染毒组后代母鼠早期胚胎发育受到显著影响 ,主要表现为回收胚胎中正常发育为囊胚的比例显著降低(P <0 .0 1 ) ,同时发育延迟胚及退化变性胚的综合比例显著升高 (P <0 .0 1 )。     

钼对小鼠后代肾脏的损伤作用

为探讨长期钼暴露对子代小鼠肾功能的影响,采用2月龄清洁级小鼠60只(雌雄比2∶1),随机分为4组(每组10只雌鼠,5只雄鼠),雌雄分开饲养。饮水中加入不同剂量Na2MoO4.2H2O组成空白对照组、低钼组(100mg/L)、中钼组(200mg/L)和高钼组(400mg/L),4周后雌雄合笼饲养,待其产仔。妊娠期和哺乳期母鼠仍按原分组给予不同剂量的钼。仔鼠断奶后,同样按原分组给予不同剂量的钼。饲养8周后,再从每组后代中随机选取雌性小鼠10只和雄性小鼠5只合笼饲养,待其产仔。如此反复,使小鼠繁殖4代。选取第3代(F2)、第4代(F3)小鼠眼球摘除法采血并分离血清,测定血清肌酐和尿素氮。采集肾脏测定微核率和肾组织切片。结果表明,当饮水中Na2MoO4.2H2O达到200mg/L以上时,可显著增加后代小鼠肾细胞微核率(P<0.05)和血清肌酐浓度(P<0.05),降低血清尿素氮含量(P<0.05)。说明钼制剂可对小鼠后代肾脏产生损伤作用。     

白消安对性成熟公鸡睾丸发育的影响

将96只165日龄健康公鸡随机分为3组,分别行腹腔内单次注射法注射白消安0、50、60 mg/kg鸡重,分别在白消安处理后5、10、15、20、25、30 d研究其对鸡睾丸形态和曲细精管组织学方面的影响.结果表明,白消安(50 mg/kg、60 mg/kg)可显著降低鸡的睾丸质量并严重损伤鸡睾丸曲细精管和生精细胞,是制备精原干细胞移植受体的合适剂量.     

川楝素腹腔注射对小白鼠半数致死量(LD50)的测定

用寇氏(karber)法测定了川楝素腹腔注射对小鼠的半数致死量(LD50).取90只小鼠,雌雄各半,体重(25±2)g.以10%丙二醇生理盐水为溶媒,按序贯法测出川楝素腹腔注射小鼠100%致死率;将高剂量组与低剂量组的组间剂量比设定为1.2,染毒测定其LD50.结果川楝素腹腔注射对小鼠的LD50为13.84 mg/kg,95%可信限为12.46～15.37 mg/kg.     

银杏叶对小鼠抗炎镇痛作用的研究

目的：观察不同剂量银杏叶水煎醇沉液对小鼠的抗炎、镇痛作用。方法：采用二甲苯诱导小鼠耳壳肿胀法,50只小鼠随机均分5组,分别为银杏叶水煎醇沉液腹腔注射高（10.0 g/kg）、中（5.0 g/kg）、低（2.5 g/kg）剂量组,空白对照组腹腔注射等量生理盐水,阳性对照组腹腔注射地塞米松（10 mg/kg）,连续给药6 d,测定小鼠耳廓的肿胀率和肿胀抑制率;采用热板法测定小鼠的镇痛作用,取合格小鼠100只随机均分10组,分别为银杏叶水煎醇沉液腹腔注射和水煎液灌胃高（10.0 g/kg）、中（5.0 g/kg）、低（2.5 g/kg）剂量组,空白对照组腹腔注射和灌胃等量生理盐水,阳性对照组腹腔注射和灌胃安乃近（20 mg/kg）,给药后30 m in测定小鼠的痛阈值的变化。结果：腹腔注射银杏叶水煎醇沉液各剂量组小鼠耳廓肿胀率均低于生理盐水组（P〈0.01）,其肿胀抑制率以高剂量组最高;与生理盐水组比较,腹腔注射银杏叶水煎醇沉液各个剂量组痛阈值均明显提高（P〈0.01）;灌胃给药高剂量组有镇痛作用（P〈0.01）。结论：银杏叶水煎醇沉液腹腔注射对小鼠具有较强的抗炎和镇痛作用,灌胃给药镇痛效果相对较差。     

红茂草水提取物腹腔注射对小鼠半数致死量的测定

用寇氏法测定了红茂草水提取物腹腔注射小鼠的半数致死量(LD50)。取70只昆明系小白鼠,雌雄各半,体重(20±2)g,按序贯法测出红茂草水提取物腹腔注射小鼠100%致死率的最小剂量和0%致死率的最大剂量,染毒测定其LD50。结果红茂草水提取物腹腔注射小鼠的LD50为1777.5 mg/kg,95%可信限为1585.7mg/kg~1992.5 mg/kg。     

The effect of the non-antibiotic growth stimulators, Carbadox and Cyadox, on reproduction in laboratory animals

The effect of growth stimulators Carbadox and Cyadox was studied in laboratory rats and mice as exerted on their fertility, gravidity, embryo ontogenesis, and genetic efficacy of these drugs was also tested. In all tests one dose approaching the dose used in practice and multiple doses were administered. No antifertility effects were observed in either sex of rats, slight reduction in fertility was found in treated male mice. No teratogenic effect was observed, but both stimulators acted highly embryotoxically. Irrespective of the dose, genetic hazard occurred, influencing the first stages of spermatogenesis (spermatogony), and increasing the incidence ob abnormalities of spermatozoon heads after Carbadox treatment. In all tests Cyadox was less harmful than Carbadox. The results show that it is somewhat hazardous to use both growth stimulators in the period of animal reproduction.     

Bisphenol-A (BPA) affects reproductive formation across generations in mice

To understand effects of Bisphenol-A (BPA) exposure on the reproductive organ across generations, we analyzed morphology of the uterus and ovary, and the methylation pattern of HOXA10 gene of the 2(nd) generation. Pregnant mice (F0) were treated with sc injection of BPA in sesame oil at various doses of 0-1,000 mg/kg Bwt on days 12-16 of gestation. Their offspring (F1) were bred by foster mice, and the offspring (F2) from F1 mice were prepared. That is, F1 mice experienced in utero BPA exposure during the developmental period of reproductive organs, while F2 mice did not at all. Using these F2 mice, the present study was carried out. Comparing to the control, the body weights in BPA exposure groups were significantly increased. Correlating with the increase of body weight, the relative weights of the ovary and uterus in each group were decreased. The histological analysis revealed expansion or emphraxis of the uterine lumen and partial loss of the uterine epithelium. Unmethylation of HOXA10 gene in the uterus was observed in the intron region. The present study suggested that BPA exposure to F0 mice could affect reproductive organ of F2 mice who were not exposed to BPA.     

Chemical modulation of 3-methylindole toxicosis in mice: effect on bronchiolar and olfactory mucosal injury

C57BL/6N mice were treated to induce tolerance, to modulate the mixed function oxidase system or to deplete glutathione (GSH) before injection with 400 mg 3-methylindole (3MI)/kg. Effect of pretreatment was determined by histologic comparison of pulmonary and nasal lesions 24 hours after 3MI. beta-Naphthoflavone and 3MI pretreatment significantly decreased 3MI-induced bronchiolar epithelial damage in male and female mice, while phenobarbital protection was significant only in female mice. Only beta-naphthoflavone decreased nasal olfactory epithelial damage. Pretreatment with piperonyl butoxide, SKF 525-A, or alpha-naphthoflavone had no significant effect on development of lesions. Diethylmaleate pretreatment significantly increased mortality and bronchiolar damage in both sexes. Significant differences between male and female mice were not detected in any group. The results suggest that pretreatment with low doses of 3MI or induction of cytochrome P-448 or P-450 protects against 3MI toxicosis while GSH depletion increases mortality and pulmonary lesions.     

Assessment of fertility and reproductive toxicity in adult female mice after long-term exposure to Pueraria mirifica herb

The present study investigated the effects of long-term administration of Pueraria mirifica (PM) at non-toxic doses on the ovarian function and fertility of adult female mice based on evaluation of hematological and biochemical parameters. Female mice were divided into 4 groups (36 mice/group). Groups 1-3 were orally treated with a dose of 0 (PM-0), 10 (PM-10) or 100 mg/kg BW/day PM (PM-100), and group 4 was subcutaneously injected with 200 mug/kg BW/day of synthetic estrogen diethylstilbestrol (DES). The treatment schedule was separated into treatment and post-treatment periods. The duration of each period was 8 weeks. The PM-10 mice exhibited regular estrous cycles, while the PM-100 and DES treatments induced prolonged estrous cycles. Although no changes were observed in the uterus and ovary weights of the mice after the PM-100 and DES treatments, hyperplasia of the uterine endothelium and a decrease in the number of growing ovarian follicles were detected. The changes in the ovarian histologies of the PM-100 and DES mice were related to reductions in the levels of LH and FSH, which subsequently caused a decrease in mating efficiency. Once the PM mice were able to copulate, they were capable of successfully becoming pregnant and mothering offspring. No abnormalities were observed in the external morphologies and reproductive organ weights of the 50-day-old offspring. In conclusion, our results suggest that long-term exposure to 100 mg/kg BW of PM has adverse effects on the mating efficiency and reproduction of adult female mice and that administration of 10 mg/kg BW of PM does not induce any changes in the hypothalamic-pituitary-ovarian-uterine axis.     

Recovery of fertility in quinestrol‐treated or diethylstilbestrol‐treated mice: Implications for rodent management

Fertility control is an alternative strategy to traditional culling for the management of rodent pests. Previous studies have demonstrated that quinestrol is a potential contraceptive for male rodents, but the recovery of fertility in quinestrol‐treated rodents has not been evaluated. This study used C57BL/6J mice to evaluate the recovery rate of male fertility after the administration of quinestrol. Diethylstilbestrol (DES), a non‐steroid estrogenic compound, was used for comparison. Different groups of mice were treated with 1 mg/kg quinestrol, 1 mg/kg DES, or castor oil separately for 7 days. These mice were then killed on days 8, 22 and 50 respectively. Our results indicated that the weight of epididymides and seminal vesicles decreased significantly on days 8 and 22 in quinestrol/DES‐treated mice, with extensive histological changes in the seminiferous tubules. Sperm concentrations in the cauda epididymal fluid were significantly reduced on days 8 and 22 in both quinestrol and DES treatment groups and on day 50 for the DES, but not the quinestrol group. Further analysis revealed that DES‐treated mice exhibited a higher proportion of abnormal sperm accumulation in the epididymis, indicating that the normal sperm transportation to the cauda epididymis was blocked. Our results indicate that the anti‐fertility effects on male mice given quinestrol were of shorter duration than for those receiving DES at the dose of 1 mg/kg body weight.     

白消安对睾丸的毒害作用及机制探讨

白消安（busulfan）对精子发生具有较强毒害作用,可导致雄性不育,是制备精原干细胞（spermatogonial stem cells,SSCs）移植受体的理想药剂。睾丸炎对生精机能也有重要影响,甚至能导致雄性不育。然而,白消安损害血睾屏障（blood-testis barrier,BTB）,影响精子发生的机制尚不清楚,尚不知其是否会导致非传染性睾丸炎症,并影响细胞因子分泌,损害生育能力。因此,本文综述了白消安对BTB的破坏作用、对睾丸细胞相关功能蛋白的影响,以及白消安损伤睾丸的缓解方法,以深入揭示白消安对睾丸细胞和BTB功能与结构的毒害作用,为研发高效安全的SSCs移植受体制备技术,以及化疗药物治疗和环境毒素作用下生精机能科学防护与恢复提供科学参考。     

孕鼠暴露双酚A对仔鼠存活率、生殖激素及相关基因的影响

为了研究孕鼠在孕期暴露双酚A（bisphenol A,BPA）对仔鼠生殖激素及相关基因的影响,试验将40只昆明孕鼠随机分为A、B、C、D共4组,每组10只。其中A组为对照组,饲喂普通鼠粮;B、C、D组孕鼠整个妊娠期（妊娠1 d至分娩）分别按每只鼠每天50、500、2 500 mg/kg体重给予BPA,待孕鼠自然分娩,观察记录仔鼠死亡情况。至仔鼠性成熟（56日龄）剖杀仔鼠,摘取睾丸或卵巢称重并计算脏器指数,HE染色观察卵巢或睾丸组织结构的变化,ELISA试剂盒分析仔鼠血清睾酮（T）、促卵泡素（FSH）及雌二醇（E₂）水平,免疫组织化学方法检测仔鼠睾丸或卵巢Bax、Bcl-2蛋白的表达,实时荧光定量PCR检测仔鼠睾丸StAR、CYP11a或卵巢AMH、Kitlg mRNA表达。结果显示,孕鼠暴露BPA极显著增加了仔鼠死亡率（P<0.01）,显著降低了仔鼠睾丸重（P<0.05）。ELISA检测结果表明,孕鼠暴露BPA极显著降低了仔鼠T（♂）及FSH（♀）含量（P<0.01）,极显著升高了仔鼠（♀） E₂水平（P<0.01）。HE染色结果显示,随BPA剂量增加,仔鼠睾丸组织损伤严重,间质细胞减少;卵巢组织结构随BPA剂量增大,空泡逐渐增多,黄体颗粒数量逐渐减少。免疫组化结果显示,孕鼠暴露BPA增加了仔鼠睾丸或卵巢组织中Bax阳性蛋白表达,减少了Bcl-2阳性蛋白表达,显著降低了雄性仔鼠StAR mRNA表达量（P<0.05）;B、D组雄性仔鼠CYP11a mRNA表达量极显著降低（P<0.01）,而C组CYP11a mRNA表达量极显著升高（P<0.01）;C、D组雌鼠Kitlg mRNA表达极显著降低（P<0.01）,AMH mRNA表达量显著升高（P<0.05）。本试验结果表明,孕鼠妊娠期暴露不同剂量BPA增加了仔鼠死亡率,扰乱了生殖激素平衡和睾丸/卵巢中相关凋亡蛋白及生殖基因表达。     

Effects of Maternal Exposure to Bisphenol A on Survival Rate,Reproductive Hormones and Relative Genes of Offspring Mice

This study was aimed to investigate the reproductive toxicity of bisphenol A (BPA) exposed to the mother on the offsprings mice. Forty pregnant Kunming mice were randomly divided into 4 groups, i.e. groups A, B, C and D with 10 mice in each group. Group A was the control group and the mice received conventional feeds, mice in groups B, C and D were given 50,500 and 2 500 mg/kg BW BPA in feedstuffs during the whole gestation period (from 1 d to parturition), respectively. The death rates of the offsprings were calculated every week. The offspring mice were sacrificed at 56 days of age (at puberty). The morphology of ovary and testicular tissues were observed with hematoxylin-eosin (HE) staining. The levels of estradiol (E₂), follicle stimulating hormone (FSH), testosterone (T) in mice serum were detected with ELISA Kit. The protein levels of Bax and Bcl-2 in ovary or testicular tissues were detected with immunohistochemistry, and the StAR,CYP11a mRNA levels in testicular tissues, the AMH, Kitlg mRNA levels in ovary were measured using Real-time PCR. The results showed that exposure of BPA to the mother extremely significantly increased the mortality (P<0.01),and significantly reduced the testicular weight of offspring mice (P<0.05). Maternal exposure to BPA extremely significantly reduced the levels of T (♂) and FSH(♀) (P<0.01),and extremely significantly elevated E₂ (♀) level in offspring mice (P<0.01). BPA exposure damaged the testicular with less leydig cells and ovarian tissues with more vacuoles and less corpus granules in offspring mice. Immunohistochemistry results revealed that maternal exposure to BPA increased the Bax protein level and decreased the Bcl-2 protein level of testicular and ovary tissues in offspring mice. BPA significantly reduced the StAR mRNA expression in male offsprings (P<0.05). However, the mRNA level of CYP11a in groups B and D extremely significantly decreased while group C showed an significant elevation in male offsprings (P<0.01). The expression levels of Kitlg mRNA in groups C and D were decreased extremely significantly in female offsprings (P<0.01), the AMH mRNA expression in groups C and D increased significantly (P<0.05). The conclusion indicated that pregnant mice exposed to different doses of BPA had harmful effects on survival rate in offspring mice, and impact the reproductive hormones, proteins and genes expression.     

山豆根多糖对感染PRRSV小鼠脾脏细胞因子水平的影响

探讨山豆根多糖对PRRSV感染小鼠脾淋巴细胞分泌细胞因子水平的影响。将70只昆明种小鼠随机分为7组(A组、B组、C组、D组、E组、F组、G组),每组10只,雌雄各半,依据前期已经建立氧化应激模型的感染条件,D组、E组、F组、G组小鼠于试验第1、2、3天分别采用口服、滴鼻和腹腔注射3种途径联合感染PRRSV病毒原液1.0mL/只,A组、B组、C组给予生理盐水1.0mL/只。第4、5、6天,A、D组小鼠分别腹腔注射生理盐水,0.2mL/10g。B组小鼠腹腔注射5.0mg/kg的脂多糖(LPS)溶液,C组、E组、F组、G组小鼠分别腹腔注射不同剂量的山豆根多糖(200、50、100、200mg/kg)。供试小鼠均于第14天处死,并取其脾脏制备匀浆。采用ELISA检测脾匀浆中TNF-α、IL-1β、IL-6、IL-8、IL-10和MCP-1等细胞因子的水平。结果显示,PRRSV感染小鼠后能升高小鼠脾脏匀浆内TNF-α、IL-1β、IL-6、IL-8、IL-10和MCP-1水平,50mg/kg~100mg/kg剂量的山豆根多糖能降低上述细胞因子的水平。结果表明,山豆根多糖能有效降低PRRSV感染小鼠脾脏细胞因子的水平。     

Consequences of endocrine disrupting chemicals on reproductive endocrine function in birds: establishing reliable end points of exposure

It has been difficult to establish reliable indices of exposure to endocrine disrupting chemicals (EDCs) appropriate for a variety of avian species because of a vast array of reproductive strategies. Data from mammals, reptiles and fish provide insight on likely mechanisms of action for EDCs. However, many of the effects of EDCs are weaker than the actions of the native hormones, making it difficult to assess adverse effects in domestic and wild birds. It is clear that differential sensitivity to EDCs exists across species, due to the timing and mode of exposure, compound toxicity and age of the individual. Our studies on EDCs are conducted in the quail model system, with focus on reproductive endocrine, neuroendocrine and behavioral responses. Studies have included EDC exposure, either by egg injection or via diet. Results from egg injection studies showed the following: (1) estradiol administered by embryonic day 12 demasculinized male sexual behavior, altered hypothalamic neurotransmitters and reduced hen day production and fertility in a dose dependent fashion, (2) methoxychlor (MXC) or vinclozolin impaired male sexual behavior in adult quail and (3) DDE exposure impaired reproductive and immune related end points. Two-generation studies were conducted on Japanese and northern bobwhite quail with dietary methoxychlor (MXC) exposure (0, 5 and 10 ppm) beginning in adults (P1), continuing in their offspring (F1), with F2 offspring raised on control diet. MXC exposure impaired male sexual behavior, hypothalamic catecholamines and plasma steroid hormones. Moreover, MXC exposure had reproductive consequences observable at both the lower and higher doses of MXC in F1 and F2 generations. These data demonstrate that embryonic EDC exposure interferes with sexual differentiation of neural systems that direct reproduction.