Reproductive Capacity in a Pulmonate Snail (Physa gyrina Say)

1954 ◽  
Vol 88 (840) ◽  
pp. 159-164 ◽  
Author(s):  
Robert M. DeWitt
Keyword(s):  
Reproductive Capacity ◽  
Pulmonate Snail ◽  
Physa Gyrina

Trematode Community Structure in the Pulmonate Snail Physa gyrina

1993 ◽  
Vol 79 (2) ◽  
pp. 205 ◽  
Author(s):  
Scott D. Snyder ◽  
Gerald W. Esch
Keyword(s):  
Community Structure ◽  
Pulmonate Snail ◽  
Physa Gyrina

Ultrastructural Effects of Acute Kepone Treatment in Rats

1976 ◽  
Vol 34 ◽  
pp. 286-287
Author(s):  
Richard L. Klein ◽  
Åsa K. Thureson-Klein ◽  
Harihara M. Mehendale
Keyword(s):  
Neurological Disorders ◽  
Corn Oil ◽  
Preliminary Investigation ◽  
Reproductive Capacity ◽  
Ultrastructural Changes ◽  
Lipid Deposition ◽  
Severe Toxicity ◽  
Sprague Dawley ◽  
Ether Anesthesia ◽  
Sprague Dawley Rats

KeponeR (decachlorooctahydro-1,3,4-metheno-2H-cyclobuta[cd]pentalen-2-one) is an insecticide effective against ants and roaches. It can cause severe toxicity in fishes, birds, rodents and man. Prominent effects include hepatic lipid deposition and hypertrophy, impairment of reproductive capacity and neurological disorders. Mitochondrial oligomycin-sensitive Mg2+-ATPase is also inhibited. The present study is a preliminary investigation of tissue ultrastructural changes accompanying physiological signs of acute toxicity, which after two days treatment include: pronounced hypersensitivity and tremor, various degrees of anorexia and adipsia, and decreased weight gain.Three different series of adult male Sprague-Dawley rats (Charles River or CD-I) were treated by intubation with Kepone in corn oil at a dose of 50 mg per kg for 3 successive days or at 200 ppm in food for 8 days. After ether anesthesia, rats were immediately perfused via a cannula in the left ventricle with 4% p-formaldehyde and 0.5% glutaraldehyde in Millonig's phosphate buffer at pH 7.2 for 20-30 min at 22°C.

FINDING FACTORS OF SURVIVAL THE YOUNG OF MARINE HERRING MIGRATING IN THE NORTHERN PART OF THE CASPIAN SEA

2017 ◽  
pp. 19-25
Author(s):  
Tatiana Stanislavovna Zubkova
Keyword(s):  
First Generation ◽  
Environmental Influence ◽  
Reproductive Capacity ◽  
Individual Species ◽  
Survival Ratio ◽  
The Caspian Sea ◽  
Foraging Area ◽  
Starting Point ◽  
Feeding Assessment ◽  
Predatory Fishes

The objects of research are three species of Caspian migrating herrings (Dolginsk herring ( Alosa brashnikowi ), big-eyed shad ( Alosa saposchnikowii ), Caspian shad ( Alosa caspia caspia )). The work considers two biological aspects of herring reproduction: dependence of number of underyearlings on the number of females in the end of feeding; assessment of survival rate of herring juveniles from the stage of fish egg to the stage of underyearlings. Besides fecundity of individual species, scientists take into account sex ratio in spawning populations, population fecundity, loss of reproductive capacity due to the resorption in unscreened roe. The materials obtained within 2009-2015 show that the dependence of herring underyearling number on the number of females arriving at spawning ground is extremely low. Despite a great number of females on the spawning grounds, the reasons of decreasing number of the first generation can be different: unfavorable hydrological and hydrochemical environment in foraging area, insufficient nutritive base, rescheduling of the spawning etc. The varying number of underyearlings from year to year is more pronounced with predatory fishes: the Dolginsk herring - 2.1 times, big-eyed shad - 1.7 times. The underyearling number of zoo-plankton feeder - Caspian shad is consistently high with minimal yearly variations. The young of Caspian shad have the highest survival ratio (0.0122); the young of predatory herring species the ratio is lower: Dolginsk herring is 4 times less (0.0031), big-eyed shad - 5 times less (0.0024). The data on herring survival from stage of a fish egg to an underyearling stage will become a starting point in the investigation of the environmental influence on to the new herring generations.

Assessment of reproductive capacity of representatives of ancestral complexes and especially their selection of seed in dry conditions

2019 ◽  
pp. 1-23
Author(s):  
А.В. Семенютина ◽  
С.Е. Лазарев ◽  
К.А. Мельник
Keyword(s):  
Weather Conditions ◽  
Reproductive Capacity ◽  
Limiting Factors ◽  
Scientific Center ◽  
Gleditsia Triacanthos ◽  
Biological Potential ◽  
Forest Reclamation ◽  
Dry Conditions ◽  
Generative Phase ◽  
Selection Of

Представители родовых комплексов Robinia (Робиния), Gleditsia (Гледичия) относятся к экономически важным и перспективным, для деградированных ландшафтов засушливого региона, видам растений. Несмотря на это до последнего времени отсутствуют сведения по многим видам этих родовых комплексов, связанные с вопросами экологических основ семеноведения и их репродуктивной способности в условиях светлокаштановых почв Волгоградской области. Все это направлено на выявление и расширение перспективных ареалов культивирования для лесомелиорации и озеленения населенных пунктов. Цель исследований изучение репродуктивной способности представителей родовых комплексов Robinia (Робиния), Gleditsia (Гледичия) в коллекциях ФНЦ агроэкологии РАН и выявление особенностей их селекционного семеноведения для лесомелиорации и озеленения населенных пунктов в сухостепных условиях. Объектами исследований являлись виды и формы рода Robinia: R. viscosa Vent. R. neomexicana Gray. R. pseudoacacia L. R. neomexicana х pseudoacacia, и Gleditsia (G. triacanthos L., G. triacanthos L. f. inermis, G. caspica Desf, G. texana Sarg., G. aquatica, G. japonica, G. caspica, G. sinensis), произрастающие в кластерных участках коллекций ФНЦ агроэкологии РАН, кадастр 34:34:000000:122, 34:34:060061:10. Разработка основ селекционного семеноведения базируется на изучении репродуктивных особенностей выделенных для целевого использования собственных биоресурсов с учетом возможностей всестороннего изучения генеративных качеств и оценки биологического потенциала. Выявлено, что стабильность плодоношения фиксируется через несколько лет после вступления в генеративную фазу: у Robinia и Gleditsia 67 лет. Первое цветение у Gleditsia triacanthos и G. texana, G. aquatica наблюдалось в возрасте 5 лет, G. japonica 6, G. caspica и G. sinensis 8 лет. Завязываемость плодов зависит не только от возраста растения, но и от погодных условий во время цветения. На семенную продуктивность влияет количество выпавших осадков и сумма активных температур в период созревания плодов. Формирование более крупных плодов и семян наблюдается в возрасте до 15 лет. В результате исследований (20172019 гг.) выявлено влияние лимитирующих факторов на биологический потенциал цветения, плодоношения и семенную продуктивность для определения ареалов их культивирования. Representatives of generic systems Robinia, Gleditsia are economically important and promising for degraded arid landscapes of the region, types of plants. Despite this, until recently, there is no information on many types of these generic complexes related to the environmental foundations of seed and their reproductive capacity in light chestnut soils of the Volgograd region. All this is aimed at identifying and expanding promising areas of cultivation for forest reclamation and greening of settlements. The aim of the research is to study the reproductive capacity of representatives of ancestral complexes Robinia, Gleditsia in the collections of the Federal scientific center for Agroecology Russian Academy of Sciences and the identifying features of their selection of seed for forest reclamation and landscaping of settlements in the dry steppe conditions. The objects of research were species and forms of the genus Robinia: R. viscosa Vent. R. neomexicana Gray. R. pseudoacacia L. R. neomexicana x pseudoacacia and Gleditsia (G. triacanthos L., G. triacanthos L. f. inermis, G. caspica Desf, G. texana Sarg., G. aquatica, G. japonica, G. caspica, G. sinensis), growing in the cluster areas of collections of FSC Agroecology RAS, cadastre 34:34:000000:122, 34:34:060061:10. The development of the principles of seed breeding is based on the study of reproductive characteristics of the allocated for the targeted use of their own bioresources, taking into account the possibilities of a comprehensive study of generative qualities and assessment of biological potential. It was found that the stability of fruiting is fixed a few years after entering the generative phase: Robinia and Gleditsia 67 years. The first flowering in Gleditsia triacanthos and G. texana, G. aquatica was observed at the age of 5 years, G. japonica 6, G. caspica and G. sinensis 8 years. Fruit setability depends not only on the age of the plant, but also on weather conditions during flowering. Seed productivity is affected by the amount of precipitation and the amount of active temperatures during the ripening period. The formation of larger fruits and seeds is observed in the age of 15 years. As a result of studies (20172019), the influence of limiting factors on the biological potential of flowering, fruiting and seed production to determine the areas of their cultivation was revealed.

The Benefits of Biotreatment for Reducing the Effects of Pulp and Paper Mill Effluents on Fish Reproduction in Laboratory Tests

2008 ◽  
Vol 43 (2-3) ◽  
pp. 161-171 ◽  
Author(s):  
Pierre Martel ◽  
Tibor Kovacs ◽  
Virginie Bérubé
Keyword(s):  
Laboratory Tests ◽  
Egg Production ◽  
Pimephales Promelas ◽  
Paper Mill ◽  
Pulp And Paper ◽  
Reproductive Capacity ◽  
Fish Reproduction ◽  
Pulp And Paper Mill ◽  
Paper Mill Effluents ◽  
Gonad Size

Abstract Pulp and paper mill effluents have been reported to cause changes in reproductive indicators of fish in laboratory and field studies. These changes include reduced egg production and gonad size, and altered hormone levels and expression of secondary sex characteristics. We examined the performance of biotreatment plants for their potential in abating effects of pulp and paper mill effluents on fish reproduction under laboratory conditions. A bleached kraft mill effluent (BKME) treated in an aerated lagoon and a thermomechanical pulp mill effluent (TMPE) treated by aerobic sludge in a sequential batch reactor were selected for study. Mature fathead minnows (Pimephales promelas) were exposed to effluents before and after biotreatment under continuous renewal conditions for 21 days. Egg production was monitored daily, while morphometric parameters (length, weight, gonad size), secondary sexual characteristics, and steroid hormone and vitellogenin levels were measured at the end of the effluent exposure. The effluent from both mills before biotreatment impaired the reproductive capacity of minnows (egg production) at concentrations of 10 and 20% vol/vol, but not at 2% vol/vol. Exposure to biotreated effluents from both mills at concentrations of 2, 10, 20, and 40% vol/vol caused no significant differences in overall reproductive capacity of minnows as compared with controls. These results indicate that biotreatment can significantly improve the quality of a BKME and an effluent from a TMP mill with respect to the reproductive capacity of fish as determined in laboratory tests.

Nitrifying biotower upsets due to snails and their control

1997 ◽  
Vol 36 (1) ◽  
pp. 247-254 ◽  
Author(s):  
Gudny Palsdottir ◽  
Paul L. Bishop
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Operating Parameters ◽  
Control Mechanisms ◽  
Successful Operation ◽  
Snail Control ◽  
The North ◽  
Physa Gyrina

The primary purpose of this study was to find the proper operating parameters for successful operation of the nitrification biotowers at the North Regional Wastewater Treatment Plant in Dayton, Ohio, and to recommend an operational protocol to prevent future failures. This plant is subject to regular, periodic biotower upsets. It was found that these upsets are correlated with blooms of snails (Physa gyrina) which it is believed graze the biofilm and devour the nitrifying organisms. Snail control mechanisms are under investigation.

Novel aspects of endometrial function: a biological sensor of embryo quality and driver of pregnancy success

2012 ◽  
Vol 24 (1) ◽  
pp. 68 ◽  
Author(s):  
Olivier Sandra ◽  
Nadéra Mansouri-Attia ◽  
Richard G. Lea
Keyword(s):  
Developmental Stages ◽  
Assisted Reproductive Technologies ◽  
Uterine Cavity ◽  
Reproductive Technologies ◽  
Biological Properties ◽  
Reproductive Capacity ◽  
Epigenetic Alterations ◽  
Uterine Receptivity ◽  
Blastocyst Development ◽  
Developmental Potential

Successful pregnancy depends on complex biological processes that are regulated temporally and spatially throughout gestation. The molecular basis of these processes have been examined in relation to gamete quality, early blastocyst development and placental function, and data have been generated showing perturbations of these developmental stages by environmental insults or embryo biotechnologies. The developmental period falling between the entry of the blastocyst into the uterine cavity to implantation has also been examined in terms of the biological function of the endometrium. Indeed several mechanisms underlying uterine receptivity, controlled by maternal factors, and the maternal recognition of pregnancy, requiring conceptus-produced signals, have been clarified. Nevertheless, recent data based on experimental perturbations have unveiled unexpected biological properties of the endometrium (sensor/driver) that make this tissue a dynamic and reactive entity. Persistent or transient modifications in organisation and functionality of the endometrium can dramatically affect pre-implantation embryo trajectory through epigenetic alterations with lasting consequences on later stages of pregnancy, including placentation, fetal development, pregnancy outcome and post-natal health. Developing diagnostic and prognostic tools based on endometrial factors may enable the assessment of maternal reproductive capacity and/or the developmental potential of the embryo, particularly when assisted reproductive technologies are applied.

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