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1.
Sensitivity of three algal species, Chlorella vulgaris, Scenedesmus acutus and Pseudanabaena galeata to herbicides atrazine and chlorsulfuron was studied using single species toxicity tests. Organisms were exposed to different concentrations of these herbicides and the algal growth was measured by turbidity at 750 nm. Atrazine appeared to be the most inhibitory to algae growth. 96 hr EbC50 of atrazine was: 1.3, 0.014, 0.014 mg/1 for C. saccharophila, S. acutus and P. galeata, respectively and 96 hr EbC50 of chlorsulfuron was 74.5 mg/1 for C.saccharophila, 0.19 mg/1 for S. acutus and 21.1 mg/1 for P. galeata 相似文献
2.
Extractable atrazine and its metabolites (hydroxyatrazine, deethylatrazine and deisopropylatrazine) were evaluated in agricultural
soils from the temperate humid zone (Galicia, NW Spain) under laboratory conditions. The experiment was performed with five
soils with different properties (organic C, soil texture and atrazine application history), both unamended and treated with
atrazine at field application rate. Measurements of the atrazine compounds were made at different time intervals (1, 3, 6,
9 and 12 weeks) during a 3-month incubation period. Results showed that only hydroxyatrazine was detected in the extractable
fraction of the unamended soils, with values remaining relatively constant throughout the incubation period. Atrazine addition
notably increased the concentration of the parent compound and its degradation products; deisopropylatrazine and hydroxyatrazine
were the main metabolites detected in the extractable fraction of the treated soils, whereas deethylatrazine was not detected.
After 7 days incubation, values of total extractable residues, expressed as percentage of initially added atrazine, ranged
from 75 to 86% (25–68% of atrazine, 7–11% of hydroxyatrazine and 9–57% of deisopropylatrazine). The values decreased rapidly
during the first 3 weeks of incubation, showing values of 2–8% in soils with higher atrazine application and from 28 to 30%
in soils with lower application history. At the end of the incubation, 2–8% of total extractable residues were still detected
(0–4% of atrazine, 2–3% of hydroxyatrazine and 0–2% of deisopropylatrazine), indicating a residual effect of atrazine addition.
These variations in the extractable fraction indicated that most added atrazine was rapidly degraded, especially in soils
with higher application history. 相似文献
3.
Funda Gülcü Bulmuş Fatih Sakin Gaffari Türk Mustafa Sönmez Kadir Servi 《毒物与环境化学》2013,95(6):1019-1029
The aim of this study was to investigate the effects of curcumin (CUR) on antioxidant status, body weight (BW) gains, and some reproductive parameters in male rats exposed to subchronic doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Thirty-two rats were divided into four groups. The first group was kept as control. The second group (TCDD group) was given TCDD at a dose of 50 ng·kg?1 BW per day; the third group (CUR group) was treated with CUR at a dose of 80 mg·kg?1 BW per day. The fourth group (TCDD + CUR group) was given TCDD and CUR at the same doses simultaneously. Malondialdehyde (MDA) levels were significantly increased in the TCDD group. In addition, TCDD exposure decreased liver superoxide dismutase (SOD) activity, catalase (CAT) activities of kidney and brain, glutathione peroxidase (GSH-Px) activities of liver, kidney, and brain, and glutathione levels of liver, kidney, and heart. However, CUR treatment with TCDD exposure decreased MDA levels in all tissues and increased SOD activities of liver, kidney, and brain, CAT activity of heart, and GSH-Px activities of heart and brain. TCDD caused a decrease in BW gain, and CUR partially eliminated this effect of TCDD. In addition, while reproductive organ weights, sperm concentration, and sperm motility tended to decrease with TCDD exposure, these effects tended to be close to normal levels by CUR treatment. In conclusion, CUR was seen to be effective in the treatment and prevention of toxicity induced by subchronic TCDD exposure. 相似文献
4.
5.
孕激素是广泛使用的高生物活性药物,其残留广泛存在于水环境中,对水生生物造成潜在威胁。本论文研究孕激素左炔诺孕酮(LNG)长期暴露对雄性斑马鱼的生殖毒性。将斑马鱼胚胎暴露于环境相关浓度的LNG(10, 33, 100 ng·L~(-1))至性成熟(受精后142 d),得到100%的雄性斑马鱼。将得到的雄鱼与未暴露的雌鱼配对,结果发现100 ng·L~(-1) LNG处理组雄鱼使得未暴露雌鱼产卵的数量较对照组雄鱼使得未暴露雌鱼产卵的数量显著减少。33和100 ng·L~(-1)处理组雄鱼与未暴露雌鱼配对所得子代在受精后7 d内的存活率较对照组雄鱼与未暴露雌鱼配对所得子代的存活率显著降低。33 ng·L~(-1) LNG显著升高总活力、活跃精子活力、平均路径速度、直线运动速度、曲线运动速度等精子活力参数,但其他浓度的LNG并不影响精子的活力。LNG在33和100 ng·L~(-1)的浓度下显著降低雄鱼血浆中11-酮基睾酮(11-KT)的含量,且在3个浓度下均显著降低雄鱼血浆中雌二醇(E2)的含量,但对睾酮(T)无明显影响。此外,LNG暴露可干扰雄鱼大脑和精巢中孕激素受体(npr, mprα, mprβ)、雌激素受体(erα, erβ)以及雄激素受体(ar)的转录,可能通过这些受体途径参与生殖调控。研究结果表明环境相关浓度的左炔诺孕酮长期暴露可导致雄性斑马鱼的生殖内分泌干扰效应,并提示:仅雄鱼单独受孕激素暴露影响,也可能对鱼类种群的生殖产生深远影响。 相似文献
6.
Laurent Keller Liselotte Sundström Michel Chapuisat 《Behavioral ecology and sociobiology》1997,41(1):11-15
The relative number of workers and female sexuals fathered by two males mated with a queen were directly assessed using microsatellite
and allozyme markers in field colonies of the ants Formica exsecta and F. truncorum. In both species one of the two males consistently fathered more offspring than the other. There was, however, no evidence
that one male might be particularly successful in fathering a disproportionally high proportion of female sexuals relative
to the proportion of workers. Moreover, in F. exsecta, the proportions of worker pupae and worker adults fathered by each male did not differ significantly between cohorts. The
most likely explanation for this pattern is that females store different amounts of sperm from the two males they mated with.
Received: 10 January 1997 / Accepted after revision: 22 March 1997 相似文献
7.
Ishaque AB Tchounwou PB Wilson BA Washington T 《Journal of environmental biology / Academy of Environmental Biology, India》2004,25(1):1-6
Embryos of the Japanese medaka (Oryzias latipes) were exposed to serial concentrations of atrazine (0, 25, 50, and 100 ppm) and arsenic trioxide (0, 0.025, 0.05, 0.1 ppm) until hatching. Stasis of circulation, blood islands, titanic convulsions, tube heart and mortality were observed in atrazine-treated embryos. Each endpoint exhibited a concentration-response relationship. Only 4% of the embryos hatched in the 25 ppm, and none in the 50 and 100 ppm, probably due to cell death attributed to the embryos' inability to break from the chorion. With arsenic exposure, hatching was inversely correlated to chemical concentration: 86%, 75% and 54% for 0.025, 0.05 and 0.1 ppm, respectively. Hatching periods were also reduced from 7-13 days in controls to 7-11 days in arsenic-treated embryos. This observation was more pronounced with the 0.05 ppm concentration, showing a reduction of about 4 days. Despite this shortage in hatching time, there were no observable morphological abnormalities, as seen with atrazine. The ecological significance of these findings and implications for the development of sublethal toxicity tests using Japanese medaka embryos are important. 相似文献
8.
Dispersal in red squirrels (Sciurus vulgaris) is not sex-biased and strict philopatry is rare. The immigration pattern suggests that nearly all animals have to disperse away from the natal site and that dispersal in this species is the outcome of local (intrasexual) competition. If this interpretation is correct, we predict that dispersers and residents, of both sexes, should have equal survival rates and lifetime reproductive success. Body mass, longevity, reproductive success and dominance rank of 34 resident offspring (settling within 400 m of the natal range) and 70 immigrants (dispersers) were compared. Immigrants did not weigh less than residents as adults, nor did they have a higher mortality during the pre-setding period. Survival rate, lifetime reproductive success (females) and the proportion of males obtaining a high dominance rank were similar for residents and dispersers, and no sex effect was found on either of the parameters studied. These results are consistent with the hypothesis that local competition determines whether an individual disperses further away or settles close to its birthplace. 相似文献
9.
Xiao-Ming Ma Xi Chen Shi-Wei Ma P.J. Coenraads Jing Liu Chun-Mei Zhang 《毒物与环境化学》2013,95(9):1715-1727
The chronic effects low-dose 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were examined on protein expression profiles in rat testis, sperm, and serum gonadal hormones. A total of 32 male rats were randomly divided into three TCDD-exposed groups, administered either 140, 350, or 875 ng TCDD/kg/week for 29 weeks, respectively, and one control group receiving only corn oil. The proteins from rat testis were separated and analyzed by two-dimensional gel electrophoresis and mass spectrometry. TCDD induced significant decreases in sperm counts and serum gonadal hormone levels compared with controls. TCDD altered testicular protein expression levels. Several interesting volume-altered proteins that were related to the reproductive toxicities or other toxicities of TCDD were identified. Among these proteins, PERF15 was the only down-regulated protein; sperm protein SSP411, ubiquitin carboxyl-terminal hydrolase L-3, and eukaryotic translation elongation factor 1 gamma were up-regulated by TCDD. The differentially expressed proteins and other data provide further insight into the mechanisms of reproductive toxicity mediated by low-dose TCDD exposure. 相似文献
10.
Joanna M. Setchell Marie Charpentier E. Jean Wickings 《Behavioral ecology and sociobiology》2005,58(5):474-485
In sexually dimorphic, polygynous species, where males provide little parental care and competition between males for access to fertile females is high, sexual selection theory predicts sex differences in age-specific reproductive output and mortality profiles, and greater variance in lifetime reproductive success in males than in females. We examined age-specific reproductive output, mortality patterns and the extent and causes of variation in reproductive success for a semi-free-ranging colony of mandrills (Mandrillus sphinx, Cercopithecidae) in Franceville, Gabon, using long-term (20 year) demographic records and microsatellite parentage analysis. Although differences in the demography and feeding ecology of this closed, provisioned colony, in comparison with wild mandrills, limit interpretation of our results, sex differences in reproductive output and mortality showed the patterns predicted by sexual selection theory. Mortality was higher in males than in females after sexual maturity, and lifespan was significantly shorter in males (mean 14 year) than in females (>22 year). Age at first reproduction was significantly earlier in females (mean 4.2 year) than in males (11.6 year), and male reproductive output declined earlier. All females of breeding age produced offspring; while only 17 of 53 sexually mature males (32%) sired. Males sired a maximum of 41 offspring, versus 17 in females, and variance in male reproductive output was significantly greater than in females at all ages. The most important influence on variation in lifetime reproductive output in both sexes was joint variation between length of the breeding period and reproductive rate, due to lower reproductive rates in younger animals. Finally, social rank significantly influenced reproductive output in both sexes: high-ranking females began their reproductive careers earlier and had a higher subsequent reproductive rate than low-ranking females, while males that achieved top rank during their career sired far more offspring than males that did not.Electronic Supplementary Material Supplementary material is available for this article at 相似文献
11.
外来植物紫茎泽兰(Eupatorlum adenophorum)入侵我国西南地区并造成了严重的生态灾难,通过研究不同林木种群下紫茎泽兰的生长特性和发生规律,有助于从生态学角度为紫茎泽兰的综合防控提供事实依据。我们分别于2009、2011和2012年在西昌袁家山上开展了不同人工林木群落下紫茎泽兰营养生长和生殖生长特性的调查。调查研究的结果表明,阔叶林(青冈林)、阔叶针叶混交林(油茶柏树混交林)和阔叶混交林(油茶青冈混交林)下光照强度显著低于两种针叶林(落叶松林和柏树林)和空旷地,光照强度较空旷地减少率均在90%以上。空旷地紫茎泽兰的发生密度可达到111-218株·m-2,两种针叶林(落叶松林和柏树林)对紫茎泽兰的发生表现出一定的抑制作用,抑制率能达到46.2%~77.1%。油茶柏树混交林和青冈林下紫茎泽兰只有零星发生,对紫茎泽兰发生抑制率3年均在90%以上,而在油茶青冈混交林下未发现有紫茎泽兰发生。空旷地紫茎泽兰株高和分枝数均要显著高于其他人工林木群落,单株株高可达160.5~180.3cm,单株分枝数达到14.9~17.4,其中两种针叶林下紫茎泽兰的株高和分枝数要显著高于两种混交林和青冈林,株高达到59.5~113.4cm,单株分枝数为6.4~14.8。此外种植人工林木也显著抑制了紫茎泽兰的开花结实,空旷地紫茎泽兰单株种子量能达到8314~15410粒,两种针叶林(落叶松林和柏树林)下紫茎泽兰单株种子发生量为1330-4666-3粒,而两种混交林和青冈林下紫茎泽兰只有零星开花或不开花结实。相关性分析结果显示,光照强度的大小与紫茎泽兰的发生密度、株高、分枝数、单株花苞数、单株种子数都呈显著正相关,即光照强度显著影响着紫茎泽兰的发生密度、生长以及开花结实。阔叶林下光照强度的减弱是导致紫茎泽兰发生量减少原因之一。开展植树造林,采用种植青冈林、油茶青冈、油茶柏树混交林等阔叶混栽的方式对紫茎泽兰的发生不仅能起到显著的生态控制效果,而且能绿化荒山,给农民带来经济效益。 相似文献
12.
Ewelina Wawryk-Gawda Michał K. Zarobkiewicz Katarzyna Chłapek Patrycja Chylińska-Wrzos Barbara Jodłowska-Jędrych 《毒物与环境化学》2019,101(7-8):404-419
AbstractThe use of electronic cigarettes increases as a supposedly healthier form of nicotine consumption, but safety of vaping remains uncertain. In this study, we assessed whether the use of electronic cigarettes increases the risk of infertility in male rats. Malformations of sperm morphology were more frequent in nicotine-exposed groups than in the control group. Vacuolization of seminiferous epithelium, reduction of spermatogenesis, increased apoptosis of spermatogonia and spermatocytes, and acceleration of degeneration of testes were observed. The male reproductive organs are slightly less affected by vaping than by smoking. Nevertheless, in consequence both may lead to the reduction of fertility. 相似文献
13.
Katrin Brauch Keith Hodges Antje Engelhardt Kerstin Fuhrmann Eric Shaw Michael Heistermann 《Behavioral ecology and sociobiology》2008,62(9):1453-1466
In a wide variety of species, male reproductive success is determined by contest for access to females. Among multi-male primate
groups, however, factors in addition to male competitive ability may also influence paternity outcome, although their exact
nature and force is still largely unclear. Here, we have investigated in a group of free-ranging Barbary macaques whether
paternity is determined on the pre- or postcopulatory level and how male competitive ability and female direct mate choice
during the female fertile phase are related to male reproductive success. Behavioural observations were combined with faecal
hormone analysis for timing of the fertile phase (13 cycles, 8 females) and genetic paternity analysis (n = 12). During the fertile phase, complete monopolisation of females did not occur. Females were consorted for only 49% of
observation time, and all females had ejaculatory copulations with several males. Thus, in all cases, paternity was determined
on the postcopulatory level. More than 80% of infants were sired by high-ranking males, and this reproductive skew was related
to both, male competitive ability and female direct mate choice as high-ranking males spent more time in consort with females
than low-ranking males, and females solicited copulations mainly from dominant males. As most ejaculatory copulations were
female-initiated, female direct mate choice appeared to have the highest impact on male reproductive success. However, female
preference was not directly translated into paternity, as fathers were not preferred over non-fathers in terms of solicitation,
consortship and mating behaviour. Collectively, our data show that in the Barbary macaque, both sexes significantly influence
male mating success, but that sperm of several males generally compete within the female reproductive tract and that therefore
paternity is determined by mechanisms operating at the postcopulatory level. 相似文献
14.
多溴二苯醚(PBDEs)虽然已在一些国家禁止生产和使用,商品五溴和八溴二苯醚也在2009年被列入《关于持久性有机污染物(POPs)的斯德哥尔摩公约》受控范围内,但目前学术界对PBDEs的毒理学效应及其机制尤其是环境剂量效应的认识并不十分清楚. 论文从甲状腺干扰、神经毒性、生殖内分泌干扰3个方面介绍了近年来PBDEs毒理学研究的进展,分析了该领域研究中存在的几个问题,提出今后应大力开展环境相关剂量下PBDEs及代谢物的毒性研究,以推进对实际环境中PBDEs真实毒性的认识;同时探索能够反映PBDEs毒性的非创性生物标记物,为开展PBDEs人体健康影响的流行病学调查提供线索. 相似文献
15.
Alternative reproductive tactics and male-dimorphism in the horned beetle Onthophagus acuminatus (Coleoptera: Scarabaeidae) 总被引:6,自引:0,他引:6
Douglas J. Emlen 《Behavioral ecology and sociobiology》1997,41(5):335-341
Adult dung beetles (Onthophagus acuminatus) exhibit continuous variation in body size resulting from differential nutritional conditions experienced during larval development.
Males of this species have a pair of horns that protrude from the base of the head, and the lengths of these horns are bimodally
distributed in natural populations. Males growing larger than a threshold body size develop long horns, and males that do
not achieve this size grow only rudimentary horns or no horns at all. Previous studies of other horned beetle species have
shown that horned and hornless males often have different types of reproductive behavior. Here I describe the mating behaviors
of the two male morphs of O. acuminatus during encounters with females. Females excavate tunnels beneath dung, where they feed, mate and provision eggs. Large, horned
males were found to guard entrances to tunnels containing females. These males fought with all other males that attempted
to enter these tunnels. In contrast, small, hornless males encountered females by sneaking into tunnels guarded by other males.
In many instances, this was accomplished by digging new tunnels that intercepted the guarded tunnels below ground. Side-tunneling
behavior allowed sneaking males to enter tunnels beneath the guarding male, and mate with females undetected. Both overall
body size and relative horn length significantly affected the outcome of fights over tunnel ownership. These results suggest
that alternative reproductive tactics may favor divergence in male horn morphology, with long horns favored in males large
enough to guard tunnels, and hornlessness favored in smaller males that adopt the “sneaking” behavioral alternative.
Received: 12 October 1996 / Accepted after revision: 8 August 1997 相似文献
16.
Parental investment, potential reproductive rates, and mating system in the strawberry dart-poison frog, Dendrobates pumilio 总被引:1,自引:0,他引:1
We studied the effect of relative parental investment on potential reproductive rates (PRRs) to explain sex differences in
selectivity and competition in the dart-poison frog Dendrobates pumilio. We recorded the reproductive behavior of this species in a Costa Rican lowland rainforest for almost 6 months. Females spent
more time on parental care than males, and `time out' estimates suggest that PRRs of males are much higher than than those
of females, rendering females the limiting sex in the mating process. Males defended territories that provide suitable calling
sites, space for courtship and oviposition, and prevent interference by competitors. Male mating success was highly variable,
from 0 to 12 matings, and was significantly correlated with calling activity and average perch height, but was independent
of body size and weight. Estimates of opportunity for sexual selection and variation in male mating success are given. The
mating system is polygamous: males and females mated several times with different mates. Females were more selective than
males and may sample males between matings. The discrepancy in PRRs between the sexes due to differences in parental investment
and the prolonged breeding season is sufficient to explain the observed mating pattern i.e., selective females, high variance
in male mating success, and the considerable opportunity for sexual selection.
Received: 9 June 1998 / Received in revised form: 27 March 1999 / Accepted: 3 April 1999 相似文献
17.
Recent models of choosiness in mate choice have identified two particularly important factors: the potential reproductive
rate (PRR) of the choosing sex relative to that of the chosen sex, and the variation in quality of potential mates. This experimental
study tested how these factors affected choosiness in male and female sand gobies, Pomatoschistus minutus. We manipulated relative PRR by means of water temperature, and mate quality by means of body length. The choosing male or
female was offered a choice between two mates with either a small or a large difference in body length representing a small
or a large variation in mate quality. Choosiness was measured as (1) preference for the larger mate, and (2) as whether or
not spawning occurred with the smaller mate, while the larger mate was visible but screened off. We found that females preferred
large males, and that their level of choosiness was affected by variation in male quality, but not by their own relative PRR.
Males, on the other hand, seemed unselective in all treatments and were in general more likely than females to spawn with
their provided partner. This suggests that in the sand goby, variation in male mate quality has a greater influence than relative
PRR on facultative changes in female choosiness. However, a general difference in PRR between males and females may be one
important factor explaining the observed sex difference in choosiness.
Received: 17 April 2000 / Revised: 24 June 2000 / Accepted: 17 July 2000 相似文献
18.
Summary Adult male tree lizards, Urosaurus ornatus, practise alternative (territorial or sneaker/satellite) reproductive strategies that are correlated with differences in throat color and body size. In this study we raised tree lizards from hatching in the laboratory to examine the question of whether the phenotypic expression of secondary sex coloration and body size can be facultatively influenced by social or abiotic environmental factors. We compared males reared in the laboratory under different social and environmental conditions to males in the field and found no effect of different conditions on phenotypic differentiation (Figs. 2–4). Thus, phenotypic differences between morphs probably result largely from nonfacultative expression of different genotypes. This suggests that alternative male morphs practise a mixed evolutionary stable strategy (ESS) rather than one morph making the best of a bad situation. However, in the context of ESS theory it is difficult to explain our further result that the nonterritorial morph in this species grows faster and reaches a larger adult body size than the territorial morph (Fig. 5). 相似文献
19.
Qaisar Mahmood Arshid Pervez Syeda Shaima Meryem Muhammad Waseem Zahid Ullah 《毒物与环境化学》2015,97(5):634-639
The aim of this study was designed to determine the influence of welding fumes on oxidative stress in humans and the role of metals. A questionnaire was designed to collect information regarding personal characteristics, including age, weight, height, and medical history; life style such as smoking status and exercise habits; and occupational history such as working history, working environment, employment duration, and use of protective equipment. Body mass index (BMI) in kg/m2 was then calculated for each participant. Blood samples were also drawn to determine malondialdehyde (MDA) levels and various metals in plasma. Significantly higher plasma MDA (4.08 µg/L) was observed as compared to controls (1.61 µg/L). Blood metal analysis also showed elevated level of metals in welders for cadmium, chromium, lead,and nickel. Data indicated that workers occupationally exposed to welding fumes for prolong periods possessed higher metal levels associated with increased oxidative stress as evidenced by elevated MDA levels. 相似文献
20.
In irrigated maize areas of an important Portuguese agricultural area, Ribatejo and Oeste Region, alachlor, atrazine and metolachlor were detected in ground water. During the study performed from 1996 to 1998 atrazine was the herbicide that showed the highest frequency of detection. In the 177 ground water samples collected 62% were contaminated with atrazine, 30% with alachlor and 12% with metolachlor. All these herbicides were detected both in ground water for human consumption and for irrigation, in some cases above 0.1 ug/L. The maximum levels quantified were 13μg/L for alachlor, 30μg/L for atrazine and 56 μg/L for metolachlor. Seasonal variation of residues in ground water it is also presented through several examples of studies performed during the period 1991–1999. 相似文献