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Sample records for nematode egg hatch

  1. In vitro hatching of Trichuris suis eggs

    DEFF Research Database (Denmark)

    Vejzagic, Nermina; Thamsborg, Stig Milan; Kringel, Helene

    2015-01-01

    Eggs of the pig whipworm, Trichuris suis ova (TSO), are currently tested in human clinical trials for their potential immunomodulatory capacity. The biological potency of TSO (egg viability and infectivity) is traditionally assessed in Göttingen minipigs as the establishment of intestinal larvae...... after inoculation with a known number of eggs. To minimize testing in animal models, development of an in vitro egg hatching assay is proposed as a reliable, cost-effective, and a faster alternative to test the egg viability. The present study aimed to investigate the influence of different chemical......, physical, and biological factors on egg hatching. Thus, in a series of experiments and in different combinations, the eggs were stimulated with glass beads, artificial gastric juice, bile salt and trypsin solution, fermentation gut medium, or stimulated with mucosal scrapings from the ileum and the large...

  2. essential oil as hatching egg disinfectant

    African Journals Online (AJOL)

    STORAGESEVER

    2010-04-26

    Apr 26, 2010 ... disinfectant for hatching egg obtained from broiler breeder flock. Oregano essential ... contamination rate, hatchability of fertile egg, body weight at 21 and 42 days, body weight gain and total feed ... successful healthy hatchlings. Several ...... Insecticidal properties of essential plant oils against the mosquito.

  3. Effect of Egg Orientation on Malposition in Hatching Eggs

    Directory of Open Access Journals (Sweden)

    İsmail Durmuş

    2015-09-01

    Full Text Available This research was conducted to determine the effects of orientation in the hatching eggs on hatching results and position disorders, so the eggs were placed in incubator for 3 groups as orientation of normal, horizontal and small end up. In this study, 1680 hatching eggs were divided into 3 groups with 7 replicates of 80 eggs in each. Hatchability of fertile eggs, malformation ratio, malposition ratio, weight loss ratio, chick quality, embryo death ratios in the early, middle and late stage of embriogenesis and mortality ratio were investigated in this research. There were significant differences among the groups in terms of egg weight loss ratio, embryo death in the late stage of embriogenesis, malposition ratio, hatching rate , whereas no significant differences among the groups in respect to malformation ratio, chick quality, embryo death in early and late embriogenesis. It was determined that the late embrionic mortality increased because of the position errors in case of hatching eggs orientation and the head of the embryo in small end up of eggs.

  4. Salmonella contamination of hatching and table eggs: a comparison.

    OpenAIRE

    Poppe, C; Duncan, C L; Mazzocco, A

    1998-01-01

    This study determined and compared Salmonella contamination rates of pools of surplus, early and culled hatching eggs from layer and broiler breeder flocks, and of pools of early and regular table eggs from layer flocks. Each pool contained 6 eggs. Five methods were used for the isolation of Salmonella. Nine of 126 pools of culled layer hatching eggs, 2 of 126 pools of surplus layer hatching eggs, and one of 126 pools of early layer hatching eggs were contaminated with Salmonella. All 126 poo...

  5. Selection for high levamisole resistance in Haemonchus contortus monitored with an egg-hatch assay

    NARCIS (Netherlands)

    Hoekstra, R.; Borgsteede, F.H.M.; Boersema, J.H.; Roos, M.H.

    1997-01-01

    To investigate the characteristics of selection for levamisole resistance in Haemonchus contortus, the consecutive nematode generations of an in vivo selection were monitored with a newly developed egg-hatch assay. The in vivo selection was started with a population not previously exposed to any

  6. 29 CFR 780.211 - Contract production of hatching eggs.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Contract production of hatching eggs. 780.211 Section 780... eggs. It is common practice for hatcherymen to enter into arrangements with farmer poultry raisers for the production of hatching eggs which the hatchery agrees to buy. Ordinarily, the farmer furnishes the...

  7. Bacteria stimulate hatching of yellow fever mosquito eggs.

    Directory of Open Access Journals (Sweden)

    Loganathan Ponnusamy

    Full Text Available BACKGROUND: Aedes aegypti Linnaeus is a peridomestic mosquito that lays desiccation-resistant eggs in water-filled human-made containers. Previous investigations connected egg hatching with declining dissolved oxygen (DO that is associated with bacterial growth. However, past studies failed to uncouple DO from other potential stimulatory factors and they contained little quantitative information about the microbial community; consequently, a direct role for bacteria or compounds associated with bacteria in stimulating egg hatching cannot be dismissed. METHODOLOGY/PRINCIPAL FINDINGS: Environmental factors stimulating hatch of Ae. aegypti eggs were investigated using non-sterile and sterile white oak leaf (WOL infusions and a bacterial culture composed of a mix of 14 species originally isolated from bamboo leaf infusion. In WOL infusion with active microbes, 92.4% of eggs hatched in 2-h at an average DO concentration of 2.4 ppm. A 24-h old bacterial culture with a DO concentration of 0.73 ppm also stimulated 95.2% of eggs hatch within 1-h. In contrast, only 4.0% of eggs hatched in sterile infusion, whose DO averaged 7.4 ppm. Effects of bacteria were uncoupled from DO by exposing eggs to bacterial cells suspended in NaCl solution. Over a 4-h exposure period, 93.8% of eggs hatched while DO concentration changed minimally from 7.62 to 7.50 ppm. Removal of bacteria by ultra-filtration and cell-free filtrate resulted in only 52.0% of eggs hatching after 4-h at an average DO concentration of 5.5 ppm. CONCLUSIONS/SIGNIFICANCE: Collectively, the results provide compelling evidence that bacteria or water-soluble compounds secreted by bacteria, not just low DO concentration, stimulate hatching of Ae. aegypti eggs. However, the specific cues involved remain to be identified. These research findings contribute new insight into an important aspect of the oviposition biology of Ae. aegypti, a virus vector of global importance, providing the basis for a new

  8. Temperature effects on copepod egg hatching: does acclimatization matter?

    DEFF Research Database (Denmark)

    Hansen, Benni Winding; Drillet, Guillaume; Kozmér, A.

    2010-01-01

    This report investigates female sizes, egg sizes and egg hatching rates in relation to temperature for the near-shore calanoid copepod Acartia tonsa cultured at 6, 9, 14 and 24°C for several generations to achieve acclimatization. Inverse size relationships of eggs and females were revealed...... with increasing temperature. Eggs produced at 6°C were 85 ± 4 µm in diameter, but decreased to 80 ± 3 µm at 24°C. Female cephalothorax length was 840 ± 52 and 692 ± 39 µm at 9 and 24°C, respectively. Parallel hatching experiments were performed between non-acclimatized and acclimatized cultures across a range...... of temperatures reflecting natural conditions in Danish waters. A greater fraction of eggs enter quiescence as temperature declines. Eggs were able to hatch at temperatures as low as 1.5°C. Final egg hatching success increased with temperature. Acclimatization of the copepods resulted in a lower maximum hatching...

  9. Bleach Solution Requirement for Hatching of Daphnia magna Resting Eggs

    Directory of Open Access Journals (Sweden)

    Catur Retnaningdyah

    2016-11-01

    Full Text Available Daphnia (water fleas belong to the zooplankton group called Cladocerans have sexual reproduction when conditions less favorable that produce diapausing eggs are enclosed in the ephippium. Hatching ephippial eggs in the laboratory is important in ecological, toxicology, genetical, and evolutionary studies. This study aims to improve the current methods of egg hatching from ephippium. Each of 50 ephippium were treated together by placing them in a glass jar and adding 50 mL bleach solution (sodium hypochlorite. Concentrations of sodium hypochlorite used in this experiment were 0%, 0.5%, 1%, 2%, 4% and 8%. These concentration treatments were crossed with the following exposure times (1, 2, 4, 8, 16, and 32 minutes. Culturing was done in 80 mL of artificial Daphnia medium, incubated in constant light and temperatures 20°C for 25 days. There were two repetitions in this experiment that were run at the same time. Result of this experiment showed that pretreatment with 0.5-8% bleach solution significantly increases the yield of total hatch rate of Daphnia magna resting eggs by about 21% over unbleached control. However, there was no significant difference among the bleach treatments. Concentration of bleach solution 0.5%, 1% and 4% significantly accelerated the time period until the first hatching (first day hatching. Difference of exposure time (1 - 32 minutes at each concentration treatments were not influence the yield of total hatch and the time period until first hatching.

  10. effects of hatching egg weight and length of storage period

    African Journals Online (AJOL)

    metinpetek

    There were no significant effects of egg storage period on body weight and feed ... chicks from all groups were reared under the same growing conditions in battery ... on hatching time, apparent fertility, hatchability of fertile and total eggs data ...

  11. Hatchery waste: nutritional evaluation of non-hatched eggs.

    Science.gov (United States)

    de Souza, M L; Jokl, L; da Silva, J M; Vieira, E C

    1978-12-01

    Hen's non-hatched eggs were processed by boiling for 30 minutes, milling in a meat grinder, and drying at 60 degrees C with continuous ventilation. The product contained 36% of protein, 27% of ether extract, 17% of ash, 10% of calcium, and 0.6% of phosphorus. The quality of the protein was comparable to that of a reference casein and of fresh egg meal, as determined by protein efficiency ratio and apparent net protein utilization.

  12. 9 CFR 94.6 - Carcasses, parts or products of carcasses, and eggs (other than hatching eggs) of poultry, game...

    Science.gov (United States)

    2010-01-01

    ... carcasses, and eggs (other than hatching eggs) of poultry, game birds, or other birds; importations from..., DEPARTMENT OF AGRICULTURE EXPORTATION AND IMPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS... § 94.6 Carcasses, parts or products of carcasses, and eggs (other than hatching eggs) of poultry, game...

  13. Artificial incubation of muscovy duck eggs : Why some eggs hatch and others do not

    NARCIS (Netherlands)

    Harun, MAS; Veeneklaas, RJ; Visser, GH; Van Kampen, M

    This study was designed to gain insight into the influence of spraying and cooling, during artificial incubation, on the embryo metabolic rate and hatching ability of Muscovy duck eggs. Three times a week 93 incubated eggs were sprayed and cooled for 0.5 h at room temperature. Daily embryo metabolic

  14. 1,10-Phenanthroline and its derivatives are novel hatching stimulants for soybean cyst nematodes.

    Science.gov (United States)

    Nonaka, Shiori; Katsuyama, Tsutomu; Kondo, Tatsuhiko; Sasaki, Yasuyuki; Asami, Tadao; Yajima, Shunsuke; Ito, Shinsaku

    2016-11-01

    Soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is a plant-parasitic nematode and one of the most serious soybean pests. Herein, we present the heterocyclic compound 1,10-phenanthroline (Phen) and its derivatives as novel hatching stimulants for SCN. Phen treatment promoted hatching of second-stage juveniles of SCNs in a concentration-dependent manner. In addition, the hatching of SCNs following treatment with Phen occurred more rapidly than that following treatment with the known hatching stimulant, glycinoeclepin A (GEA). Furthermore, the co-application of Phen and GEA enhanced SCN hatching rate compared with that of Phen or GEA alone. A structure-activity relationship study for Phen derivatives suggested that 2,2'-bipyridine is the essential structure of the SCN-hatching stimulants. These results suggest that Phen and its derivatives activate different hatching pathways of SCNs from GEA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Impact of egg disinfection of hatching eggs on the eggshell microbiome and bacterial load

    DEFF Research Database (Denmark)

    Olsen, R.; Kudirkiene, E.; Thofner, I.

    2017-01-01

    Disinfection of hatching eggs is essential to ensure high quality production of broilers. Different protocols are followed in different hatcheries; however, only limited scientific evidence on how the disinfection procedures impact the microbiome is available. The aim of the present study...... was to characterize the microbiome and aerobic bacterial load of hatching eggs before disinfection and during the subsequent disinfection steps. The study included a group of visibly clean and a group of visibly dirty eggs. For dirty eggs, an initial wash in chlorine was performed, hereafter all eggs were submitted...... to two times fumigation and finally spray disinfection. The eggshell microbiome was characterized by sequencing of the total amount of 16S rRNA extracted from each sample, consisting of shell surface swabs of five eggs from the same group. In addition, the number of colony forming units (cfu) under...

  16. Commercially laid eggs vs. discarded hatching eggs: contamination by Salmonella spp.

    Science.gov (United States)

    Kottwitz, Luciana B M; Leão, Joice Aparecida; Back, Alberto; Rodrigues, Dalia dos P; Magnani, Marciane; de Oliveira, Tereza C R M

    2013-01-01

    Salmonella enterica is frequently associated with outbreaks of human salmonellosis, and products of avian origin, such as eggs and chicken meat, are the main vehicles of its transmission. The present study describes the occurrence of different serovars of Salmonella enterica and phagotypes of S. enterica serovar Enteritidis in eggs destined for human consumption. Four thousand eggs obtained from commercial egg laying farms and one thousand discarded hatching eggs from broiler farms, which were acquired at farmers' markets and informal shops, were analyzed. Salmonella spp. was isolated from 52.0% of the discarded hatching eggs, in which the predominant serovar was Enteritidis (84.6%), and the predominant Salmonella Enteritidis phagotype (PT) was PT7 (26.9%). Salmonella spp. was not isolated from eggs obtained from commercial egg laying farms. The antimicrobial resistance profile showed that 23.1% (n = 6) of the SE strains were resistant to nalidixic acid. The results suggest that the consumption of discarded hatching eggs represents an important source of Salmonella transmission to humans.

  17. Egg clutch dehydration induces early hatching in red-eyed treefrogs, Agalychnis callidryas

    Directory of Open Access Journals (Sweden)

    María José Salica

    2017-07-01

    Full Text Available Terrestrial eggs have evolved repeatedly in tropical anurans exposing embryos to the new threat of dehydration. Red-eyed treefrogs, Agalychnis callidryas, lay eggs on plants over water. Maternally provided water allows shaded eggs in humid sites to develop to hatching without rainfall, but unshaded eggs and those in less humid sites can die from dehydration. Hatching responses of amphibian eggs to dry conditions are known from two lineages with independent origins of terrestrial eggs. Here, we experimentally tested for dehydration-induced early hatching in another lineage (Agalychnis callidryas, Phyllomedusidae, representing a third independent origin of terrestrial eggs. We also investigated how dehydration affected egg and clutch structure, and egg mortality. We collected clutches from a pond in Gamboa, Panama, and randomly allocated them to wet or dry treatments at age 1 day. Embryos hatched earlier from dry clutches than from wet clutches, accelerating hatching by ∼11%. Clutch thickness and egg diameter were affected by dehydration, diverging between treatments over time. Meanwhile, mortality in dry clutches was six-fold higher than in control clutches. With this study, early hatching responses to escape mortality from egg dehydration are now known from three anuran lineages with independent origins of terrestrial eggs, suggesting they may be widespread. Further studies are needed to understand how terrestrial amphibian eggs can respond to, or will be affected by, rapid changes in climate over the next decades.

  18. Effects of egg weight on hatchability, chick hatch-weight and ...

    African Journals Online (AJOL)

    Egg weight was positively and strongly correlated with egg hatchability (r2 = 0.727) and chick hatch-weight (r2 = 0.953). Heavier-sized eggs hatched chicks had higher mortality rates. Growth rate and live weight of the chickens were optimized at different egg weights of 56 (r2 = 0.657) and 60 (r2 = 0.870) g, respectively, ...

  19. Suspension of Egg Hatching Caused by High Humidity and Submergence in Spider Mites.

    Science.gov (United States)

    Ubara, Masashi; Osakabe, Masahiro

    2015-08-01

    We tested the effects of high humidity and submergence on egg hatching of spider mites. In both the high humidity and submergence treatments, many Tetranychus and Panonychus eggs did not hatch until after the hatching peak of the lower humidity or unsubmerged controls. However, after humidity decreased or water was drained, many eggs hatched within 1-3 h. This was observed regardless of when high humidity or submergence treatments were implemented: either immediately after oviposition or immediately before hatching was due. Normal eyespot formation was observed in most eggs in the high humidity and submergence treatments, which indicates that spider mite embryos develop even when eggs are underwater. Therefore, delays in hatching are not caused by delayed embryonic development. A delay in hatching was always observed in Panonychus citri (McGregor) but was more variable in Tetranychus urticae Koch and Tetranychus kanzawai Kishida. The high humidity and submergence treatments affected but did not suppress larval development in these species. In contrast, many Oligonychus eggs died following the high humidity treatments. In Tetranychus and Panonychus spider mites, suspension of egg hatching may mitigate the adverse effects of rainfall. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Anthelmintic activity of acetone extracts from South African plants used on egg hatching of Haemonchus contortus

    Directory of Open Access Journals (Sweden)

    Gerda Fouche

    2016-07-01

    Full Text Available The nematode, Haemonchus contortus, is responsible for major economic losses in the livestock industry. The management of parasites such as H. contortus has been through the use of synthetic parasiticides. This has resulted in the presence of residues in meat and milk, which affects food safety. The development of resistance to available anthelmintics coupled with their high cost has further complicated matters. This has led to the investigation of alternative methods to manage nematodes, including the use of plants and plant extracts as a potential source of novel anthelmintics. Acetone extracts were prepared from 15 South African plant species and their anthelmintic activity determined using the egg hatch assay (EHA. The leaf extract of Cleome gynandra had the best inhibitory activity (68% ± 3% at a concentration of 2.5 mg/mL, followed by the stem extract of Maerua angolensis (65% ± 5%. The extracts had a relatively low toxicity on Vero cells determined by the MTT (3-(4,5-dimethylthiazol-2-yl-2,5- diphenyltetrazolium bromide cellular assay.

  1. Variation in the hatching response of Ochlerotatus albifasciatus egg batches (Diptera: Culicidae in temperate Argentina

    Directory of Open Access Journals (Sweden)

    Raúl Ernesto Campos

    2006-02-01

    Full Text Available Egg hatching of winter-collected Ochlerotatus albifasciatus was studied for six months. Batches of eggs were divided into two groups, one of them was stored in the laboratory at 23°C and 12:12 photoperiod, and the other in the field under dead leaves. Every month, from July to December, eggs from the two groups were flooded under both laboratory and field conditions. Unhatched eggs were returned to the original condition and flooded two more times separated by ten-day intervals. Results show that egg diapause is expressed in different intensities, not only on eggs exposed to different conditions but also in those exposed to the same condition, even when they were laid by the same female. Successive inundations yielded incomplete hatches of eggs, and favored the hatching response in the next flooding. Low environmental temperatures before and during the flooding depressed hatching response. This shows that eggs need a warm period before flooding as well as warm temperatures during flooding, to hatch. As drought period was longer hatching response increased, but this was also accompanied by warmer environmental conditions. The experiment performed in laboratory did not show that increment. Field studies showed that a layer of dead leaves protected eggs from extreme temperatures.

  2. Delayed egg hatching of Anopheles gambiae (Diptera: Culicidae) pending water agitation.

    Science.gov (United States)

    Ebrahimi, Babak; Shakibi, Sanam; Foster, Woodbridge A

    2014-05-01

    Mosquito eggs laid on water surfaces typically hatch spontaneously soon after the embryos within them become fully formed first-instar larvae. However, we have found that Anopheles gambiae Giles, an important vector of malaria in Africa, exhibits delayed hatching until the water surface is agitated, a feature overlooked in most laboratory colonies. Agitation within 24 h postoviposition, before embryonation was complete, failed to stimulate delayed postembryonic hatching of isolated eggs on the following day (day 2), when < 1% had hatched spontaneously. However, 5 min of water agitation of these dormant pharate first-instar larvae on day 2 resulted in an almost immediate hatch of 63.3 versus 0% of nonagitated controls, plus another 3.9 versus 0.3%, respectively, during the following 24 h. With daily agitation, installment hatching occurred mainly during 2-6 d postoviposition. The mean cumulative hatch after 7 d of daily agitation was 83.1 versus 1.1% of nonagitated eggs. Experiments with eggs in groups demonstrated that egg density and activity of already-hatched larvae had no stimulatory effect. Eggs stored 1-4 wk at 25.5 or at 15.5 degrees C, and then agitated daily for 6 d at 25.5 degrees C, showed a gradual decline in viability. Viability was sustained longer at the lower temperature. Implications of agitation-induced egg hatching for rainy-season and dry-season ecology of An. gambiae are discussed. Suspended hatching and cool storage already are proving convenient for efficient mass rearing and accurate modeling of weather-based population dynamics.

  3. Effect of electron irradiation in hatching eggs experimentally inoculated with salmonella enteriditis, on hatch ability and broiler performance

    International Nuclear Information System (INIS)

    Castaneda S, M.P.

    1995-01-01

    The effect of four doses of electrons irradaition on bacteriologic population in hatching egg following experimental shell contamination with Salmonella enteriditis phage type 13 was investigated. Fresh, whole, intact raw eggs were inoculated with 10 9 Colony-Forming Units of Salmonella enteriditis, eggs were irradiated with a beam electron source at either: 0.5, 1, 2 and 3 KGy. The bacteriologic evaluation was made with Gentry's and Williams' technic. After the irradiation the groups were taken to commercial hatchery and were incubated in satndards conditions. The bacteriologic evaluation of the shell showed a significant 2.8 log reduction on the group of eggs that were irradiated with 1 KGy as compared with 0.5 KGy doses group and control group (P<0.05). A negative correlation (r=-0.93) between irradiation doses and CFU (P<0.05) was also observed. Bacteriologic evaluation of the internal shell membrane exhibited a highly significant inactivation (P<0.01) of S. enteriditis of 100% in the group of eggs irradiated at 2 and 3 kGy. A high negative correlation (r=-0.90) between irradiation doses and samples of internal structures (P<0.05) was observed. The results obtained suggested that the electrons irradiation may be use like a control system of salmonelosis on egg and like desinfection system on hatching eggs because it did not cause any effect on hatchability and broiler performance. (Author)

  4. Hatch ability, growth and some blood biochemical parameters in hatching quails following the exposure of incubated eggs to red laser

    International Nuclear Information System (INIS)

    Abu Taleb, A.M.

    2003-01-01

    A total number of 600 Japanese quail eggs were used this study. The eggs were divided into three groups then incubated. Eggs of groups one (G1) and two (G2) were exposed to 30 and 60 minutes, respectively, to the red laser rays (Laser Pointer LD-300) at 0, 7 and 14 days of embryogenesis,while group three (G3) was not treated and served as control. Hatch ability body weight and mortality were recorded weekly for each group. Furthermore, five blood samples were collected from one day old chicks at hatching and at six weeks of age from each group to determine some hematological parameters including RBCs, WBCs, PCV and Hb. Liver enzyme activities (GPT and GOT), kidney function (uric acid and creatinine), cholesterol and total lipids were determined for the 6 weeks old chicks only. The present results indicated that exposure to red to significant increase in hatch ability percentage and promoted early hatch ability and decreased embryonic mortality in treated groups (G1) and (G2) than control (G3). Significant decreases in RBCs counts, cholesterol and total lipids were found in G1 and G2. Exposure of developing embryos to red laser radiation had no significant effect on PCV in one day old hatching chicks, or RBCs and WBCs counts, PCV, GOT, uric acid creatinine in six weeks old birds. At the same time, significant increases in Hb and WBCs counts were occurred in one day old chicks and Hb and GPT in six weeks old birds. It could be concluded from the reported findings that exposure to red laser radiation may affect some factors that accelerate hatch ability and cause changes in some biochemical parameters in Japanese quails

  5. Combined Effects of Egg Age and Gamma Radiation Dosage on egg hatch of Scolytus Amygdali/guer

    International Nuclear Information System (INIS)

    Tadros, A.W.; Abdallah, F.F.; Abdelsalam, K.A.; Hashem, A.G.

    1992-01-01

    Eggs of Scolytus Amygdali were irradiated with 5 to 300 gray of gamma radiation at a dose rate of 7.87 rad/second. One-to five-day-old eggs were used. Results showed that one-and-tow-day-old eggs were the most sensitive as 100% mortality were obtained at 40 and 50 gray, respectively. Three-day-old-eggs required 100 gray to prevent hatch ability; while 300 gray were needed to prevent the 4-and 5-day-old eggs from hatching. There was 7.2-fold increase in resistance as eggs matured from 1 to 5 days measured by dosages required to produce LD 50. 2 fig

  6. Advanced Oxidation Process sanitization of hatching eggs reduces Salmonella in broiler chicks.

    Science.gov (United States)

    Rehkopf, A C; Byrd, J A; Coufal, C D; Duong, T

    2017-10-01

    The microbial quality of eggs entering the hatchery is an important critical control point for biosecurity, pathogen reduction, and food safety programs in poultry production. Developing interventions to reduce Salmonella contamination of eggs is important to improving the microbial food safety of poultry and poultry products. The hydrogen peroxide (H2O2) and ultraviolet light (UV) Advanced Oxidation Process (AOP) has been previously demonstrated to be effective in reducing Salmonella on the surface of experimentally contaminated eggs. The objective of this study was to evaluate the effect of treating eggs with an egg-sanitizing apparatus using the H2O2/UV AOP on Salmonella contamination during incubation, hatching, and in broiler chicks during grow-out. Experimentally contaminated eggs were treated using the automated H2O2/UV AOP egg sanitizer and incubated for 21 d. AOP sanitization reduced Salmonella up to 7 log10 cfu egg-1 (P Salmonella positive eggs by up to 75% (P Salmonella-positive eggs during incubation. Additionally, Salmonella was recovered from more chicks hatched from untreated eggs than from eggs treated using the H2O2/UV AOP egg sanitizer (P Salmonella contamination on the surface of eggs using the H2O2/UV AOP egg sanitizer prior to incubation may reduce the gastrointestinal colonization of chicks by Salmonella. © 2017 Poultry Science Association Inc.

  7. Cold storage effects on egg hatch in laboratory-reared Culicoides variipennis sonorensis (Diptera: Ceratopogonidae).

    Science.gov (United States)

    Hunt, G J; Tabachnick, W J

    1995-09-01

    The effects of cold storage (5 degrees C) on the hatching rates of laboratory-reared Culicoides variipennis sonorensis eggs were examined. Mortality increased with storage time. Average maximum embryo survivorship for 4 trials was 55.0 +/- 4.2 (+/- SEM) days. Alternating daily cycles of high and then low mean hatching rates occurred and possibly were due to location differences in temperature within the temperature-controlled rearing system. During cold storage at 5 degrees C, C. v. sonorensis eggs may be kept for ca. 28 days with an anticipated hatching rate of about 50%.

  8. Analysis of survival and hatching transcriptomes from potato cyst nematodes, Globodera rostochiensis and G. pallida.

    Science.gov (United States)

    Duceppe, Marc-Olivier; Lafond-Lapalme, Joël; Palomares-Rius, Juan Emilio; Sabeh, Michaël; Blok, Vivian; Moffett, Peter; Mimee, Benjamin

    2017-06-20

    Potato cyst nematodes (PCNs), Globodera rostochiensis and G. pallida, cause important economic losses. They are hard to manage because of their ability to remain dormant in soil for many years. Although general knowledge about these plant parasitic nematodes has considerably increased over the past decades, very little is known about molecular events involved in cyst dormancy and hatching, two key steps of their development. Here, we have studied the progression of PCN transcriptomes from dry cysts to hatched juveniles using RNA-Seq. We found that several cell detoxification-related genes were highly active in the dry cysts. Many genes linked to an increase of calcium and water uptake were up-regulated during transition from dormancy to hydration. Exposure of hydrated cysts to host plant root exudates resulted in different transcriptional response between species. After 48 h of exposure, G. pallida cysts showed no significant modulation of gene expression while G. rostochiensis had 278 differentially expressed genes. The first G. rostochiensis significantly up-regulated gene was observed after 8 h and was coding for a transmembrane metalloprotease. This enzyme is able to activate/inactivate peptide hormones and could be involved in a cascade of events leading to hatching. Several known effector genes were also up-regulated during hatching.

  9. Embryo malposition as a potential mechanism for mercury-induced hatching failure in bird eggs

    Science.gov (United States)

    Herring, G.; Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2010-01-01

    We examined the prevalence of embryo malpositions and deformities in relation to total mercury (THg) and selenium (Se) concentrations in American avocet (Recurvirostra americana), black-necked stilt (Himantopus mexicanus), and Forster's tern (Sterna forsteri) eggs in San Francisco Bay (CA, USA) during 2005 to 2007. Overall, 11% of embryos were malpositioned in eggs ???18 d of age (n=282) and 2% of embryos were deformed in eggs ???13 d of age (n=470). Considering only those eggs that failed to hatch (n=62), malpositions occurred in 24% of eggs ???18 d of age and deformities occurred in 7% of eggs ???13 d of age. The probability of an embryo being malpositioned increased with egg THg concentrations in Forster's terns, but not in avocets or stilts. The probability of embryo deformity was not related to egg THg concentrations in any species. Using a reduced dataset with both Se and THg concentrations measured in eggs (n=87), we found no interaction between Se and THg on the probability of an embryo being malpositioned or deformed. Results of the present study indicate that embryo malpositions were prevalent in waterbird eggs that failed to hatch and the likelihood of an embryo being malpositioned increased with egg THg concentrations in Forster's terns. We hypothesize that malpositioning of avian embryos may be one reason for mercury-related hatching failure that occurs late in incubation, but further research is needed to elucidate this potential mechanism. ?? 2010 SETAC.

  10. Hatching success in brackish water of Perca fluviatilis eggs obtained from the western Baltic Sea

    DEFF Research Database (Denmark)

    Christensen, Emil Aputsiaq Flindt; Skovrind, Mikkel; Olsen, Morten Tange

    2016-01-01

    tolerance of the eggs in vivo, and the salinities at which some populations spawn in situ (7 vs. 9.6 ‰). In the present study, hatching success of perch was determined in vivo for a Danish, western Baltic, brackish water population at salinities of 4, 7, 10 and 12 ‰. Furthermore, in order to place...... the population genetically among other European perch populations, individual egg samples were sequenced for a 390 base pair fragment of the mtDNA Dloop region. Hatching occurred at all four salinities, with no statistical differences among treatments. Successful hatching at 12 ‰ is well above salinities of 7......‰, which has previously been the highest reported from in vivo studies. This discrepancy is likely to be a result of methodological differences (e.g. different temperature) or perhaps interspecific variability in egg hatching abilities among perch populations. The perch from the present study consisted...

  11. Effect of Formalin on the Hatching Rate of eggs and Survival of ...

    African Journals Online (AJOL)

    Michael Horsfall

    1, and 1000 mgl-1 of formalin resulted in total egg mortality (0% hatching rate). In the definitive ... treatment of fish disease, particularly fungi, as in this study, where it effectively reduced fungi on eggs and larvae of ... salmon held for spawning).

  12. Effects of Injected Methylmercury on the Hatching of Common Loon (Gavia immer) Eggs

    Science.gov (United States)

    To determine the level of in ovo methylmercury (MeHg) exposure that results in detrimental effects on fitness and survival of loon embryos and hatched chicks, we conducted a field study in which we injected eggs with various doses of MeHg on day 4 of incubation. Eggs were collect...

  13. The effect of lake sediment on the hatching success of Daphnia ephippial eggs

    Directory of Open Access Journals (Sweden)

    Jacek Radzikowski

    2016-07-01

    Full Text Available A large proportion of lake-Daphnia ephippia which are shed by females in the water column sink to the bottom, where they form an assemblage of dormant stages known as an egg bank. Although the quantity of zooplankton eggs in such assemblages may exceed tens of thousands per square meter, the annual hatch from this bank is usually extremely low (from zero to a few dozens animals per square meter per year. This low-hatching phenomenon may be caused by isolation from hatching stimuli by water or sediment layers, a mechanical barrier formed by sediment that does not allow hatchlings to reach the water, or by a bet-hedging strategy of the resting eggs. The aim of our study was to determine the extent to which coverage by lake sediment may affect the hatching of Daphnia dormant eggs. The ephippia of lake-Daphnia (longispina species complex, covered by sterilized lake sediment of different thicknesses (0, 0.25, 0.5, 1, 2 and 4 cm; 4 replicates per treatment, were incubated for 8 weeks in lab controlled conditions. The results indicate that even the thinnest tested layer (0.25 cm may completely inhibit hatching of ephippial eggs. A few Daphnia neonates were observed in two (of five sediment treatments, while dozens of animals hatched in the control one. In the second experiment we determined that the sediment sterilization process did not affect the hatching proportion of ephippial eggs (when compared to the treatment with unsterilized sediments. We hypothesize that the observed inhibition of Daphnia hatching in the main experiment, which may cause a serious problem for Cladoceran populations in lakes where no sediment mixing occurs, may be caused by low light intensity, anoxic conditions or a physical barrier created by the sediment.

  14. Characteristics of Skeletal Musculature of Pheasants Hatched from Eggs of Different Eggshell Colour

    Directory of Open Access Journals (Sweden)

    Dragan Zikic

    2016-05-01

    Full Text Available The aim of this paper was to examine morphodinamics of development of skeletal musculature of pheasants hatched from eggs of different eggshell colour. Four groups of pheasant eggs (dark brown, light brown, brown/green and blue/green were incubated. Samples of skeletal musculature of leg and breast were taken during the embryonic and neonatal period of development. From taken samples histological preparations were made. In pheasants hatched from blue/green eggs the smaller diameter of leg and breast muscle cells and the higher volume density of connective tissue in leg and breast muscles were recorded. It was concluded that pheasants hatched from blue/green eggs had the weakest development of skeletal musculature, which can be related to structural differences of eggshell of various colour.

  15. Bacteria-induced egg hatching differs for Trichuris muris and Trichuris suis

    DEFF Research Database (Denmark)

    Vejzagic, Nermina; Adelfio, Roberto; Keiser, Jennifer

    2015-01-01

    BACKGROUND: Eggs of the porcine whipworm Trichuris suis are currently explored in human clinical trials as a treatment of immune-mediated diseases. In this context, only the infective, embryonated eggs, constitute the Active Pharmaceutical Ingredient (API). The rodent whipworm, Trichuris muris...... is commonly used as a laboratory model to study Trichuris biology. The embryonated eggs (containing a fully developed larva) are biologically active and will invade the large intestinal mucosa of the host. This study aims to assess the in vitro hatching of T. muris and T. suis eggs in various bacterial...... cultures as a measure for their biological activity. METHODS: Eggs of T. muris and T. suis were incubated with Escherichia coli strain (BL-21) at three concentrations in a slightly modified in vitro egg hatching assay previously developed for T. muris. Additionally, E. coli strains (M15, SG13009, PMC103...

  16. Selected egg parameters and hatching time of African catfish ...

    African Journals Online (AJOL)

    Egg weight, diameter and mean number per gram were determined for fertilized eggs from broodfish of Clarias gariepinus and Heterobranchus longifilis and F1, hybrid broodfish (C. gariepinus x H. longifilis). Mean egg weight was least in C. gariepinus (1.30 mg) followed by H. longifilis (1.80 mg) and highest in the F1 hybrid ...

  17. Anthelminthic activity of methanol extracts of Diospyros anisandra and Petiveria alliacea on cyathostomin (Nematoda: Cyathostominae) larval development and egg hatching.

    Science.gov (United States)

    Flota-Burgos, G J; Rosado-Aguilar, J A; Rodríguez-Vivas, R I; Arjona-Cambranes, K A

    2017-12-15

    Methanol extracts of plant structures are promising alternatives to traditional pharmaceutical anthelminthic treatments. An in vitro evaluation was done of how methanol extracts of Diospyros anisandra bark and leaves, and Petiveria alliacea stems and leaves, collected during the rainy and dry seasons, effected cyathostomin larval development and egg hatching. Seven concentrations (600, 300, 150, 75, 37.5, 18.7 and 9.3μg/ml) were tested using the egg hatch assay. An ANOVA was applied to identify differences between the concentrations and the controls. Fifty percent lethal concentration (LC 50 ) and the 95% confidence interval were calculated with a probit analysis. At and above 37.5μg/ml, the D. anisandra bark extracts from both seasons exhibited ≥95% egg hatch inhibition (EHI), while the D. anisandra leaf extracts had >90% EHI at and above 75μg/ml. For P. alliacea, the extracts from leaves and stems from either season exhibited >97% EHI at and above 300μg/ml, although similar efficacy was also observed at lower concentrations with the rainy season stems (75μg/ml) and leaves (150μg/ml). Values for LC 50 were lowest for the rainy season D. anisandra bark (10.2μg/ml) and leaf extracts (18.4μg/ml), followed by the rainy season P. alliacea stems extract (28.2μg/ml). In the D. anisandra extracts, EHI was largely due to its ovicidal activity (≥96% beginning at 37.5μg/ml), whereas in the P. alliacea extracts it was due to L 1 larval hatch failure (≥90% beginning at 75μg/ml). Overall, the rainy season D. anisandra bark extracts had a strong in vitro anthelminthic effect against cyathostomins by inhibiting larval development, and the rainy season P. alliacea stem extracts had a strong effect by preventing egg hatching. Both are possible control alternatives for these nematodes. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Effect of neutron irradiation on hatching rate of eggs and growth rate of chicken

    International Nuclear Information System (INIS)

    Liu Yubin; Zhao Jide; Liu Shengdian; Xy Xiuwei

    1995-01-01

    It was proved through 3 years of experiments and productions that after the eggs of AA meat chickens being irradiated by 14 MeV fast neutron, the hatching rate and the survival rate as well the weight of commercial chickens increased greatly. In addition it is found that the optimum neutron fluence for hatching and growth rate is 6.2 x 10 5 n·cm -2

  19. Assessing the role of food quality in the production and hatching of Temora longicornis eggs

    DEFF Research Database (Denmark)

    Jonasdottir, Sigrun; Visser, Andre; Jespersen, C.

    2009-01-01

    We utilized the varying fatty acid composition of phytoplankton to create 19 different food treatments based on different ratios of 5 potentially important fatty acids and offered these to the copepod Temora longicornis. Egg production and hatching was monitored and related to ingested carbon......, dietary fatty acids and the utilization of maternal fatty acid reserves. Egg production rates depended on ingested carbon and the fatty acid 20:5n-3 from the diet and from the female reserves. Hatching success showed a significant dependence on the ingested and maternal fatty acids 22:6n-3, 18:5n-3 and 18......:3n-3. Production of nauplii as a combination of egg production and hatching was highly dependent on the fatty acid 22:6n-3 and carbon ingestion. The study confirms the importance of n-3 polyunsaturated fatty acids for copepod reproduction and indicates that the female differentially utilizes its...

  20. 9 CFR 147.22 - Hatching egg sanitation.

    Science.gov (United States)

    2010-01-01

    ... cleaned and disinfected after use. Cleaning and disinfection procedures should be as outlined in § 147.24..., heater, and humidifier should be cleaned and disinfected after every egg pickup. Cleaning and disinfection procedures should be as outlined in § 147.24. (d) The egg processing area should be cleaned and...

  1. Does magnesium hardness in hatching waters affect the fertilization and hatching success of hybrid catfish eggs

    Science.gov (United States)

    Embryonic development is deemed to be the most sensitive stage in the life cycle of a teleost. As egg development takes outside the fish’s body, water hardness is one abioitic parameter, suggested to have a major effect on egg development and embryo survival. Ca2+ and Mg2+ contribute to water har...

  2. Blood vessels segmentation of hatching eggs based on fully convolutional networks

    Science.gov (United States)

    Geng, Lei; Qiu, Ling; Wu, Jun; Xiao, Zhitao

    2018-04-01

    FCN, trained end-to-end, pixels-to-pixels, predict result of each pixel. It has been widely used for semantic segmentation. In order to realize the blood vessels segmentation of hatching eggs, a method based on FCN is proposed in this paper. The training datasets are composed of patches extracted from very few images to augment data. The network combines with lower layer and deconvolution to enables precise segmentation. The proposed method frees from the problem that training deep networks need large scale samples. Experimental results on hatching eggs demonstrate that this method can yield more accurate segmentation outputs than previous researches. It provides a convenient reference for fertility detection subsequently.

  3. Effect of Some Egg Quality Traits on Hatching Results in Brown Pure Lines

    Directory of Open Access Journals (Sweden)

    İsmail Durmuş

    2016-09-01

    Full Text Available This study was conducted to determine the influence of eggshell thickness, albumen height, yolk height and haugh unit on hatching results. A total of 746 eggs, which were obtained and evaluated for egg quality parameters from 100 brown pure line hens of 42 weeks of age, were used. Eggs were collected from each hen for 12 days and individual incubation was carried out. Eggs were grouped based on quality parameters and evaluated accordingly. The findings suggested that hatchability, hatchability of fertile eggs, early, mid and late embryonic mortality did not differ in terms of haugh unit, albumen height, eggshell thickness and yolk height groups. However, early embryonic mortality was found different between the yolk height groups. No relationship was determined among albumen height, haugh unit, eggshell thickness and hatching results. There was no relation between yolk height and hatchability of fertile eggs, hatchability, mid and late embryonic mortalities but was a positive correlation with early embryonic mortality. The results of the present study demonstrate that egg quality parameters studied here had no influence on hatching results except that early embryonic mortality increased with the yolk height.

  4. MicroRNA-276 promotes egg-hatching synchrony by up-regulating brm in locusts

    Science.gov (United States)

    He, Jing; Chen, Qianquan; Wei, Yuanyuan; Jiang, Feng; Yang, Meiling; Hao, Shuguang; Guo, Xiaojiao; Chen, Dahua; Kang, Le

    2016-01-01

    Developmental synchrony, the basis of uniform swarming, migration, and sexual maturation, is an important strategy for social animals to adapt to variable environments. However, the molecular mechanisms underlying developmental synchrony are largely unexplored. The migratory locust exhibits polyphenism between gregarious and solitarious individuals, with the former displaying more synchronous sexual maturation and migration than the latter. Here, we found that the egg-hatching time of gregarious locusts was more uniform compared with solitarious locusts and that microRNA-276 (miR-276) was expressed significantly higher in both ovaries and eggs of gregarious locusts than in solitarious locusts. Interestingly, inhibiting miR-276 in gregarious females and overexpressing it in solitarious females, respectively, caused more heterochronic and synchronous hatching of progeny eggs. Moreover, miR-276 directly targeted a transcription coactivator gene, brahma (brm), resulting in its up-regulation. Knockdown of brm not only resulted in asynchronous egg hatching in gregarious locusts but also impaired the miR-276–induced synchronous egg hatching in solitarious locusts. Mechanistically, miR-276 mediated brm activation in a manner that depended on the secondary structure of brm, namely, a stem-loop around the binding site of miR-276. Collectively, our results unravel a mechanism by which miR-276 enhances brm expression to promote developmental synchrony and provide insight into regulation of developmental homeostasis and population sustaining that are closely related to biological synchrony. PMID:26729868

  5. Enterobacteriaceae and Salmonella recovered from non-sanitized and sanitized broiler hatching eggs

    Science.gov (United States)

    Sanitizing hatching eggs may reduce the chances that a flock will become colonized with Salmonella and reduce the numbers of other microorganisms, such as Enterobacteriaceae, that can depress hatchability. An experiment was conducted to determine if a quaternary-biguanide sanitizer applied as foam ...

  6. Nematodes

    International Nuclear Information System (INIS)

    Suzuki, Kenshi; Ishii, Naoaki

    1977-01-01

    Utilization of nematodes for a study of radiation biology was considered. Structure, generation, rearing method, and genetic nature of nematodes (Caenorhabditis elegans, Turbatri acetic, etc.) were given an outline. As the advantage of a study using nematodes as materials, shortness of one generation time, simplicity in structure, and smallness of the whole cells, specific regular movement, and heliotaxis to chemical substances and light were mentioned. Effect of x-ray on survival rate of nematodes and effect of ultraviolet on nematodes and their eggs were described. It was suggested that nematodes was useful for studies on aging and radiation biology, and a possibility existed that nematodes would be used in studies of cancer and malformation. (Serizawa, K.)

  7. Effect of vacuum packing and temperature on survival and hatching of strongyle eggs in faecal samples

    DEFF Research Database (Denmark)

    Sengupta, Mita Eva; Thapa, Sundar; Thamsborg, Stig Milan

    2016-01-01

    Strongyle eggs of helminths of livestock usually hatch within a few hours or days after deposition with faeces. This poses a problem when faecal sampling is performed in the field. As oxygen is needed for embryonic development, it is recommended to reduce air supply during transport and refrigerate....... The present study therefore investigated the combined effect of vacuum packing and temperature on survival of strongyle eggs and their subsequent ability to hatch and develop into L3. Fresh faecal samples were collected from calves infected with Cooperia oncophora, pigs infected with Oesophagostomum dentatum......, and horses infected with Strongylus vulgaris and cyathostomins. The samples were allocated into four treatments: vacuum packing and storage at 5 °C or 20 °C (5 V and 20 V); normal packing in plastic gloves closed with a loose knot and storage at 5 °C or 20 °C (5 N and 20 N). The number of eggs per gram...

  8. Gene expression changes in diapause or quiescent potato cyst nematode, Globodera pallida, eggs after hydration or exposure to tomato root diffusate.

    Science.gov (United States)

    Palomares-Rius, Juan Emilio; Hedley, Pete; Cock, Peter J A; Morris, Jenny A; Jones, John T; Blok, Vivian C

    2016-01-01

    Plant-parasitic nematodes (PPN) need to be adapted to survive in the absence of a suitable host or in hostile environmental conditions. Various forms of developmental arrest including hatching inhibition and dauer stages are used by PPN in order to survive these conditions and spread to other areas. Potato cyst nematodes (PCN) (Globodera pallida and G. rostochiensis) are frequently in an anhydrobiotic state, with unhatched nematode persisting for extended periods of time inside the cyst in the absence of the host. This paper shows fundamental changes in the response of quiescent and diapaused eggs of G. pallida to hydration and following exposure to tomato root diffusate (RD) using microarray gene expression analysis encompassing a broad set of genes. For the quiescent eggs, 547 genes showed differential expression following hydration vs. hydratation and RD (H-RD) treatment whereas 708 genes showed differential regulation for the diapaused eggs following these treatments. The comparison between hydrated quiescent and diapaused eggs showed marked differences, with 2,380 genes that were differentially regulated compared with 987 genes following H-RD. Hydrated quiescent and diapaused eggs were markedly different indicating differences in adaptation for long-term survival. Transport activity is highly up-regulated following H-RD and few genes were coincident between both kinds of eggs. With the quiescent eggs, the majority of genes were related to ion transport (mainly sodium), while the diapaused eggs showed a major diversity of transporters (amino acid transport, ion transport, acetylcholine or other molecules).

  9. Gene expression changes in diapause or quiescent potato cyst nematode, Globodera pallida, eggs after hydration or exposure to tomato root diffusate

    Directory of Open Access Journals (Sweden)

    Juan Emilio Palomares-Rius

    2016-02-01

    Full Text Available Plant-parasitic nematodes (PPN need to be adapted to survive in the absence of a suitable host or in hostile environmental conditions. Various forms of developmental arrest including hatching inhibition and dauer stages are used by PPN in order to survive these conditions and spread to other areas. Potato cyst nematodes (PCN (Globodera pallida and G. rostochiensis are frequently in an anhydrobiotic state, with unhatched nematode persisting for extended periods of time inside the cyst in the absence of the host. This paper shows fundamental changes in the response of quiescent and diapaused eggs of G. pallida to hydration and following exposure to tomato root diffusate (RD using microarray gene expression analysis encompassing a broad set of genes. For the quiescent eggs, 547 genes showed differential expression following hydration vs. hydratation and RD (H-RD treatment whereas 708 genes showed differential regulation for the diapaused eggs following these treatments. The comparison between hydrated quiescent and diapaused eggs showed marked differences, with 2,380 genes that were differentially regulated compared with 987 genes following H-RD. Hydrated quiescent and diapaused eggs were markedly different indicating differences in adaptation for long-term survival. Transport activity is highly up-regulated following H-RD and few genes were coincident between both kinds of eggs. With the quiescent eggs, the majority of genes were related to ion transport (mainly sodium, while the diapaused eggs showed a major diversity of transporters (amino acid transport, ion transport, acetylcholine or other molecules.

  10. Conservation of the egg envelope digestion mechanism of hatching enzyme in euteleostean fishes.

    Science.gov (United States)

    Kawaguchi, Mari; Yasumasu, Shigeki; Shimizu, Akio; Sano, Kaori; Iuchi, Ichiro; Nishida, Mutsumi

    2010-12-01

    We purified two hatching enzymes, namely high choriolytic enzyme (HCE; EC 3.4.24.67) and low choriolytic enzyme (LCE; EC 3.4.24.66), from the hatching liquid of Fundulus heteroclitus, which were named Fundulus HCE (FHCE) and Fundulus LCE (FLCE). FHCE swelled the inner layer of egg envelope, and FLCE completely digested the FHCE-swollen envelope. In addition, we cloned three Fundulus cDNAs orthologous to cDNAs for the medaka precursors of egg envelope subunit proteins (i.e. choriogenins H, H minor and L) from the female liver. Cleavage sites of FHCE and FLCE on egg envelope subunit proteins were determined by comparing the N-terminal amino acid sequences of digests with the sequences deduced from the cDNAs for egg envelope subunit proteins. FHCE and FLCE cleaved different sites of the subunit proteins. FHCE efficiently cleaved the Pro-X-Y repeat regions into tripeptides to dodecapeptides to swell the envelope, whereas FLCE cleaved the inside of the zona pellucida domain, the core structure of egg envelope subunit protein, to completely digest the FHCE-swollen envelope. A comparison showed that the positions of hatching enzyme cleavage sites on egg envelope subunit proteins were strictly conserved between Fundulus and medaka. Finally, we extended such a comparison to three other euteleosts (i.e. three-spined stickleback, spotted halibut and rainbow trout) and found that the egg envelope digestion mechanism was well conserved among them. During evolution, the egg envelope digestion by HCE and LCE orthologs was established in the lineage of euteleosts, and the mechanism is suggested to be conserved. © 2010 The Authors Journal compilation © 2010 FEBS.

  11. Correlative and dynamic imaging of the hatching biology of Schistosoma japonicum from eggs prepared by high pressure freezing.

    Directory of Open Access Journals (Sweden)

    Malcolm K Jones

    Full Text Available BACKGROUND: Schistosome eggs must traverse tissues of the intestine or bladder to escape the human host and further the life cycle. Escape from host tissues is facilitated by secretion of immuno-reactive molecules by eggs and the formation of an intense strong granulomatous response by the host which acts to exclude the egg into gut or bladder lumens. Schistosome eggs hatch on contact with freshwater, but the mechanisms of activation and hatching are poorly understood. In view of the lack of knowledge of the behaviour of egg hatching in schistosomes, we undertook a detailed dynamic and correlative study of the hatching biology of Schistosoma japonicum. METHODOLOGY/PRINCIPAL FINDINGS: Hatching eggs of S. japonicum were studied using correlative light and electron microscopy (EM. The hatching behaviour was recorded by video microscopy. EM preparative methods incorporating high pressure freezing and cryo-substitution were used to investigate ultrastructural features of the miracidium and extra-embryonic envelopes in pre-activated and activated eggs, and immediately after eggshell rupture. Lectin cytochemistry was performed on egg tissues to investigate subcellular location of specific carbohydrate groups. CONCLUSIONS/SIGNIFICANCE: The hatching of S. japonicum eggs is a striking phenomenon, whereby the larva is liberated explosively while still encapsulated within its sub-shell envelopes. The major alterations that occur in the egg during activation are scission of the outer envelope-eggshell boundary, autolysis of the cellular inner envelope, and likely hydration of abundant complex and simple polysaccharides in the lacunal space between the miracidial larva and surrounding envelopes. These observations on hatching provide insight into the dynamic activity of the eggs and the biology of schistosomes within the host.

  12. Histological Characteristics of Leg Muscles of 56-Day Old Pheasants Hatched from Eggs of Different Eggshell Colour

    Directory of Open Access Journals (Sweden)

    Dragan Zikic

    2015-05-01

    Full Text Available The aim of this paper was to examine the histological characteristics of leg muscles of pheasants hatched from eggs of a different colour. From muscle samples (M. biceps femoris of 56-day old pheasants hatched from eggs of different colour (dark brown, light brown, brown/green, blue/green histological preparations were made. Following parameters were examined: diameter of muscle cells, volume density of connective tissue in muscles, nucleo-cytoplasmatic ratio of muscle cells. Results showed that diameter of muscle cells was smaller in pheasants hatched from blue/green eggs compared to all other examinated groups. There was no differences in volume density of connective tissue in muscles between groups. Nucleo-cytoplasmatic ratio of muscle cells was higher in pheasants hatched from blue/green eggs compared to all other examinated groups. From obtained results it can be concluded that pheasants hatched from blue/green eggs had weaker muscle development than pheasants hatched from eggs of other eggshell colour. Cause of this could be related to structural differences of eggshells of various colour. This leads to weaker development of embryos and chicks hatched from blue/green eggs which reflects on differences in development of leg muscles.

  13. Ixodes pacificus Ticks Maintain Embryogenesis and Egg Hatching after Antibiotic Treatment of Rickettsia Endosymbiont

    Science.gov (United States)

    Kurlovs, Andre H.; Li, Jinze; Cheng, Du; Zhong, Jianmin

    2014-01-01

    Rickettsia is a genus of intracellular bacteria that causes a variety of diseases in humans and other mammals and associates with a diverse group of arthropods. Although Rickettsia appears to be common in ticks, most Rickettsia-tick relationships remain generally uncharacterized. The most intimate of these associations is Rickettsia species phylotype G021, a maternally and transstadially transmitted endosymbiont that resides in 100% of I. pacificus in California. We investigated the effects of this Rickettsia phylotype on I. pacificus reproductive fitness using selective antibiotic treatment. Ciprofloxacin was 10-fold more effective than tetracycline in eliminating Rickettsia from I. pacificus, and quantitative PCR results showed that eggs from the ciprofloxacin-treated ticks contained an average of 0.02 Rickettsia per egg cell as opposed to the average of 0.2 in the tetracycline-treated ticks. Ampicillin did not significantly affect the number of Rickettsia per tick cell in adults or eggs compared to the water-injected control ticks. We found no relationship between tick embryogenesis and rickettsial density in engorged I. pacificus females. Tetracycline treatment significantly delayed oviposition of I. pacificus ticks, but the antibiotic’s effect was unlikely related to Rickettsia. We also demonstrated that Rickettsia-free eggs could successfully develop into larvae without any significant decrease in hatching compared to eggs containing Rickettsia. No significant differences in the incubation period, egg hatching rate, and the number of larvae were found between any of the antibiotic-treated groups and the water-injected tick control. We concluded that Rickettsia species phylotype G021 does not have an apparent effect on embryogenesis, oviposition, and egg hatching of I. pacificus. PMID:25105893

  14. Theoretical and empirical studies on temperature and moisture loss of hatching eggs during the pre-incubation period

    NARCIS (Netherlands)

    Meijerhof, R.

    1994-01-01

    In the Netherlands, approximately 800 million hatching eggs per year are produced on highly specialized broiler breeder farms. On this farms, the eggs are produced and stored for several days. Normally once or twice a week the eggs are collected from the farms and transported to the

  15. Comparative oxygen consumption rates of subitaneous and delayed hatching eggs of the calanoid copepod Acartia tonsa (Dana)

    DEFF Research Database (Denmark)

    Hansen, Benni Winding; Drillet, Guillaume

    2013-01-01

    nanorespirometry to monitor initial oxygen consumption rate of individual eggs of the ubiquitous neritic calanoid copepod Acartia tonsa to distinguish between subitaneous and DHE. We hypothesized that subitaneous eggs exhibit higher initial oxygen consumption rates than DHE, and that initial egg oxygen consumption...... rate is correlated to the time for the individual egg to hatch. Subitaneous eggs exhibited higher initial oxygen consumption rates than DHE and there were no pattern in initial oxygen consumption rates vs. time to hatch or die from the eggs. Variability in initial oxygen consumption rates within...... batches of both subitaneous and DHE, as well as between these egg types, is prevalent. There was a continuum from sluggish- to fast metabolising eggs considering initial oxygen consumption rates most likely reflecting phenotypic variation within cohorts. No matter the individual initial egg oxygen...

  16. Hatching rate and growth rate of Nothobranchius guentheri fertilized eggs after space flight

    International Nuclear Information System (INIS)

    Guo Mingzhong; Zheng Leyun; Lin Guangji; Zhong Jianxing; Yang Huosheng; Zheng Yangfu

    2012-01-01

    Hatching, abnormal, growth and survival rate of the fertilized eggs of Nothobranchius guentheri were carried by Shenzhou 7 spacecraft were studied. The results indicated that the hatching and abnormal rate were no significant difference between the spaceflight group (99.3% and 16.8%) and ground group (97.2% and 10.4%); but the growth rate of male fish from spaceflight group was significant higher (0.094 g/d) than that of ground group (0.059 g/d), leading to the significant bigger of the male fish from spaceflight group. The survival rate of spaceflight group (66.7%) was higher than the ground group (47.9%). It was concluded that there was a higher growth and survival rate of Nothobranchius guentheri fertilized eggs after space flight. (authors)

  17. The effect of gamma irradiation on fertile eggs and hatched chick performance

    International Nuclear Information System (INIS)

    Mekkawy, S.H.

    1995-01-01

    Two handier fertile white arber acers eggs were exposed to gamma irradiation (Co 6 0) at the following levels 0, 100, 150 and 200 rad. They Were then hatched with the control eggs and hatchability, growth rate, feed consumption, feed conversion, carcass quality, carcass analysis and the blood analysis were determined. Hatchability was reduced gradually with increased radiation, but significantly, no differences in body weight between irradiated and control chicks were apparent at hatching time. At the end of the experimental 45 days, the mean heavight was that of the irradiation dose of 150 rad. The feed conversion efficiency was enhanced by the irradiation treatments, especially with the dose of 200 rad. There were no differences in the carcass quality and carcass composition between the treated and non-treated birds. The results demonstrated that, the irradiation treatments had no effects on the blood analysis of the birds. 7 tabs

  18. Fertilisation and hatching success of Atlantic cod (Gadus morhua) eggs when exposed to various concentrations of produced water

    International Nuclear Information System (INIS)

    Wong, D.; Lyons, M.; Burridge, L.; Lee, K.

    2010-01-01

    This study investigated the fertilization and hatching success of Atlantic cod (Gadus morhua) eggs that were exposed to various dilutions of produced water from a natural gas production platform. A control group of eggs was fertilized in sea water without any produced water. Another set of eggs were fertilized in sea water with 4 different concentrations of produced water and held their respective concentrations for 24 hours to evaluate the success of the fertilization. Viable fertilized eggs were transferred to 96 well plates containing fresh sea water and incubated in the dark at approximately 6 degrees C until hatch. Eggs began hatching about 14 days after fertilization (DPF), peaked at about 17 DPF, then finished hatching by 21 DPF. Analysis of PAH content in the diluted produced water showed that at 0.32 percent, 1.08 percent and 3.6 percent concentrations, the fertilization success was greater than or equal to that of the control group. However, for the 12 percent concentration, there were no viable fertilized eggs present after the 24 hour period. Survivability of eggs during sea water incubation was similar for the 0 percent, 0.32 percent and 1.08 percent treatment groups, but egg mortality increased for the 3.60 percent concentration group, to about 61.5 percent mean cumulative mortality at 6 DPF, then remained constant. The mean hatching success for all dilutions was presented.

  19. Transferases activity in blood plasma of chickens hatched from eggs irradiated during incubation by low dose gamma rays

    International Nuclear Information System (INIS)

    Kraljevic, P.; Vilic, M.; Miljanic, S.; Simpraga, M.

    2005-01-01

    In our earlier studies chickens hatched from eggs irradiated with 0.15 Gy gamma rays before incubation showed a significantly higher growth than controls during the fattening period (1-42 days). The activity of aspartate-aminotransferase (AST), alanine-aminotransferase (ALT) and plasma glucose in the same chickens were also significantly higher. These results suggested that low-dose gamma-radiation stimulated certain metabolic processes in chickens hatched from eggs irradiated before incubation. The goal of this study was to determine the effects of low-dose ionising radiation on AST and ALT activity in the blood plasma of chickens hatched from eggs irradiated during incubation. The eggs of heavy breeding chickens (Avian, line 34) were exposed to 0.15 Gy of gamma-radiation (6 0C o) on the seventh day of incubation, i.e. at the time when the organogenesis in chickens is completed. The control group of chickens hatched from non-irradiated eggs. All other conditions were the same for both groups. After hatching, blood samples were taken from the wing vein on days 1, 3, 5, 7, 10, 20, 32 and 42. The activity of both enzymes was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. On day 10, AST and ALT activity were significantly higher in the blood plasma of chickens hatched from irradiated eggs, but it significantly dropped for both enzymes on day 20. Our results indicate that exposure of eggs to low-dose gamma-radiation on the seventh day of incubation affects AST and ALT activity in the blood plasma of chickens hatched from irradiated eggs. However, this effect is somewhat different from the effects of egg exposure to low-dose gamma radiation before incubation.(author)

  20. Egg Hatch Rate and Nymphal Survival of the Bed Bug (Hemiptera: Cimicidae) After Exposure to Insecticide Sprays.

    Science.gov (United States)

    Hinson, K R; Benson, E P; Zungoli, P A; Bridges, W C; Ellis, B R

    2016-12-01

    Few studies have addressed the efficacy of insecticides used against eggs and first-instar nymphs of the bed bug, Cimex lectularius L. (Hemiptera: Cimicidae). Insect eggs are often resistant to insecticides; therefore, information on which products are effective is important. We evaluated the efficacy of four commonly used insecticide sprays applied directly to bed bug eggs. We also evaluated the efficacy of these insecticides to first-instar nymphs exposed to residuals resulting from directly spraying eggs. Temprid SC (beta-cyfluthrin, imidacloprid) was the most effective insecticide at preventing egg hatch (13% hatch rate) for pyrethroid-resistant, field-strain (Jersey City) bed bugs compared with a control (water [99% hatch rate]), Bedlam (MGK-264, sumithrin [84% hatch rate]), Demand CS (lambda-cyhalothrin [91% hatch rate]), and Phantom SC (chlorfenapyr [95% hatch rate]). Demand CS and Temprid SC were most effective at preventing egg hatch (0%) for an insecticide-susceptible (Harold Harlan) strain, followed by Bedlam (28%). Phantom SC produced a hatch rate similar to the control (97% and 96%, respectively). Harold Harlan-strain nymphs showed 100% survival for the control but 0% survival for Bedlam and Phantom SC. Jersey City-strain nymphs showed 100% survival for the control, 99% survival for Bedlam, 0% survival for Demand CS, 4% survival for Phantom SC, and 38% survival for Temprid SC. Demand CS was less effective at preventing hatch (91% hatch rate) of Jersey City-strain nymphs but was the only product to kill all nymphs (0% survival). One of the least effective products for preventing Jersey City-strain egg hatch (Phantom SC, 95% hatch rate) was the second most effective at killing nymphs, leaving only six of 141 alive. These findings indicate that survival of directly sprayed eggs and residually exposed, first-instar nymphs varies by strain, life stage, and product used. © The Authors 2016. Published by Oxford University Press on behalf of Entomological

  1. Concentration of Proteins and Protein Fractions in Blood Plasma of Chickens Hatched from Eggs Irradiated with Low Level Gamma Rays

    International Nuclear Information System (INIS)

    Kraljevic, P.; Vilic, M.; Simpraga, M.; Matisic, D.; Miljanic, S.

    2011-01-01

    In literature there are many results which have shown that low dose radiation can stimulate many physiological processes of living organism. In our earlier paper it was shown that low dose of gamma radiation has a stimulative effect upon metabolic process in chickens hatched from eggs irradiated before incubation. This was proved by increase of body weight gain and body weight, as well as by increase of two enzymes activities in blood plasma (aspartate aminotransferase and alanine aminotransferase) which play an important role in protein metabolism. Therefore, an attempt was made to determine the effect of eggs irradiation by low dose gamma rays upon concentration of total proteins and protein fractions in the blood plasma of chickens hatched from irradiated eggs. The eggs of heavy breed chickens were irradiated with a dose of 0.15 Gy gamma radiation (60Co) before incubation. Along with the chickens which were hatched from irradiated eggs, there was a control group of chickens hatched from nonirradiated eggs. All other conditions were the same for both groups of chickens. Blood samples were taken from the right jugular vein on the 1 s t and 3 r d day, or from the wing vein on days 5 and 7 after hatching. The total proteins concentration in the blood plasma was determined by the biuret method using Boehringer Mannheim GmbH optimized kits. The protein fractions (albumin, α 1 -globulin, α 2 -globulin, β- and γ-globulins) were estimated electrophoretically on Cellogel strips. The total proteins concentration was significantly decreased in blood plasma of chickens hatched from irradiated eggs on days 3 (P t h day (P 2 -globulin was decreased on days 1 (P t h day of life. Obtained results indicate that low dose of gamma radiation has mostly inhibitory effect upon concentration of total proteins and protein fractions in the blood plasma of chickens hatched from irradiated eggs before incubation. (author)

  2. Diet composition and quality for Calanus finmarchicus egg production and hatching success off south-west Iceland

    DEFF Research Database (Denmark)

    Jonasdottir, Sigrun; Gudfinnsson, H.G.; Gislason, A.

    2002-01-01

    Egg production and hatching success of the copepod Calanus finmarchicus was measured during spring and summer in the waters south-west of Iceland. Egg-production rates varied greatly, both temporally and spatially, with highest average rates found at a station with low chlorophyll-a concentrations...

  3. Evaluation of disinfectants and antiseptics to eliminate bacteria from the surface of turkey eggs and hatch gnotobiotic poults

    Science.gov (United States)

    Bird eggs and are in contact with intestinal microbiota prior to oviposition, but are protected from bacterial translocation by a glycoprotein cuticle layer, the shell and internal membranes. In a preliminary study, turkey eggs were hatched in a germ-free environment. Firmicutes 16S rRNA gene was de...

  4. Screening of non-tuber bearing Solanaceae for resistance to and induction of juvenile hatch of potato cyst nematodes and their potential for trap cropping

    NARCIS (Netherlands)

    Scholte, K.

    2000-01-01

    Ninety accessions of non-tuber bearing Solanaceae were screened for (i) resistance to and (ii) stimulatory effect on juvenile hatch of potato cyst nematodes, and (iii) their growth under temperate climatic conditions. All plant species belonging to the genus Solanum tested induced hatching but this

  5. Garlic essential oil increases rates of eggs fertilization and hatching of Rhamdia quelen larvae in an artificial incubation system

    Directory of Open Access Journals (Sweden)

    Nilton Garcia Marengoni

    Full Text Available ABSTRACT: The objective of this study was to evaluate the effects of garlic (Allium sativum essential oil on the rates of eggs fertilization and hatching and on the normal development of larvae of artificially incubated silver catfish (Rhamdia quelen. The experiment was carried out using a completely randomized experimental design with four treatments and five replicates. The treatments consisted of introducing garlic essential oil into the incubators, which used a closed system of water recirculation, at concentrations of 0, 1, 3, and 5mg L-1. Rates of eggs fertilization and larval hatching were determined at 10 and 24h after the beginning of eggs hydration. Morphology of larvae was assessed with the aid of a stereo microscope to determine the rate of normal development. The concentration of 5mg L-1 promoted better rates of eggs fertilization and larval hatching. Concentrations of garlic essential oil had a linear effect on eggs fertilization rates and larval hatching. Garlic oil did not influence the morphology of the larvae (P>0.05. It is recommended to use 5mg L-1 of garlic essential oil to promote better rates of eggs fertilization and larval hatching of artificially incubated silver catfish.

  6. Effect of electron irradiation on hatchability and broiler performance of hatching eggs

    International Nuclear Information System (INIS)

    Castaneda, S.M.P.; Tellez, I.G.; Sanchez, R.E.; Quintana, L.J.A.; Bustos, R.E.

    1996-01-01

    The irradiation of foods employs the electromagnetic ionizing energy, and the gamma ray, the X ray and the electrons are used. The electrons are reduced mass particles and have negative electric charge. The difference between the gamma rays, X-ray and electron is the penetration level. The effective range on penetration of electron accelerator depends on the energy level, in practice the penetation of an electron beam in the foods is 5 mm for MeV. The objectives of this work were to evaluate the effects of electron irradiation on the hatchability, and to evaluate the productive parameters of chicken hatching from egg irradiated with electrons. (author). 15 refs., 6 tabs

  7. How to hatch from the Common Cuckoo (Cuculus canorus) egg: implications of strong eggshells for the hatching muscle (musculus complexus)

    Czech Academy of Sciences Publication Activity Database

    Honza, Marcel; Feikusová, Kateřina; Procházka, Petr; Picman, J.

    2015-01-01

    Roč. 156, č. 3 (2015), s. 679-685 ISSN 0021-8375 R&D Projects: GA ČR(CZ) GAP506/12/2404; GA AV ČR IAA6093203 Institutional support: RVO:68081766 Keywords : Brood parasitism * Common Cuckoo * Coevolution * Adaptations * Hatching muscle * Hatching Subject RIV: EG - Zoology Impact factor: 1.419, year: 2015

  8. Fly ash effect on hatching, mortality and penetration of root-knot nematode (Meloidogyne incognita in pumpkin roots

    Directory of Open Access Journals (Sweden)

    Gufran Ahmad

    2016-09-01

    Full Text Available An experiment was conducted to observe the effect of fly ash on hatching, mortality and penetration of root-knot nematode (Meloidogyne incognita in pumpkin roots. For hatching experiment different fly ash-extract concentrations (5, 10, 20, 30, 40, and 50% were prepared. Hatching was significantly reduced in all concentrations, maximum being at 50% concentration. The mortality (% of juveniles was observed in 1, 2, 3, 4, 5, 6 and 7th days with different levels (5, 10, 20, 30, 40 and 50 % of fly ash-extract. All the levels were found harmful to juveniles. As the level was increased, the killing percentage of juveniles was also increased. Highest mortality was observed in 7th day with 50% level.For the penetration experiment, fly ash was mixed with soil to prepare different concentrations (5, 10, 20, 30, 40, and 50%. Seeds of pumpkin were grown in coffee cups filled with different mixtures. At two leaf stage, seedlings were inoculated with 2000 larvae. The penetrated larvae in roots were observed after 1, 2, 3, 4, 5, 6 and 7 days. Root penetration was found inversely proportional to concentration. Significant results in the suppression of nematode penetration were noted up to 40% concentration. However, none of the juveniles was penetrated at 50% concentration.International Journal of Environment Vol.5(3 2016, pp.66-73

  9. Eggs hatching and oncomiracidia lifespan of Dawestrema cycloancistrium, a monogenean parasitic on Arapaima gigas.

    Science.gov (United States)

    Maciel, Patricia Oliveira; Muniz, Celli Rodrigues; Alves, Rosiana Rodrigues

    2017-11-30

    Within the production chain of the Arapaima gigas (pirarucu), sanitary issues are still faced at the fingerling phase regarding infestations by the monogenean Dawestrema cycloancistrium. The present study had the objectives of describing the morphology and development phases of this parasite's eggs and oncomiracidia and determining the hatching time and lifespan of the oncomiracidia at different temperatures. D. cycloancistrium eggs were oval and elongated and had a single long appendage at one pole. The egg development was divided into four phases: embryonated egg, developing egg, larva appearance and ecloded egg. They were found in four forms: isolated in gill filaments; grouped in clusters that were anchored in a gill filament; grouped in clusters and entangled in part of a dead adult monogenean; and grouped in clusters in the environment, fixed to a substrate. Eclosion occurred after 72-96h, with faster development at 29°C and 32°C than at 24°C. The morphology of the oncomiracidia were rounded and elongated. They had two pairs of pigmented eye-spots as well as two ciliated areas located on each lateral part of the body and another on the anterior part of the body. The lifespan of the D. cycloancistrium oncomiracidia were 50 and 58h at 24°C and 27°C, respectively. Larvae were found in the mucus, indicating that the oncomiracidia penetrated the host integument. Understanding reproductive aspects of the D. cycloancistrium monogenean is important for developing specific prophylactic management strategies in aquaculture and providing valuable data for further studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Control of egg hatch ability and adult emergence of three fruit fly species in papayas by gamma irradiation

    International Nuclear Information System (INIS)

    Resilva, S.S.; Pasion, W.B.; Moy, J.H.

    1991-01-01

    The effects of gamma radiation on the oriental fruit fly, Bactrocera Dorsalis (Hendel), melon fly, Bactrocera Cucurbitae (Coquilett), and Mediterranean fruit fly, Ceratitis Capitata (Weidemann) were studied. Melon fly was determined to be the most susceptible of the three species. A dosage of 550 Gy rendered the eggs 100% sterile when irradiated in papayas at 4-6 hours before hatching. Oriental and mediterranean fruit flies were found to be more resistant, requiring doses of 750 and 850 Gy, respectively. A dose of only 100 Gy was needed to inhibit adult eclosion when the three species were treated at third instar larvae. Warm water treatment at 49 0 C for 20 minutes was found sufficient in preventing the hatching of any egg in the infested papaya fruits. However, since eggs may hatch before the warm-water treatment can be applied, a combination of irradiation treatment using 100 Gy is recommended for disinfestation of papaya fruits. (author). 17 refs.; 3 tabs

  11. High temperatures and absence of light affect the hatching of resting eggs of Daphnia in the tropics

    Directory of Open Access Journals (Sweden)

    Thécia A.S.V. Paes

    2016-03-01

    Full Text Available Temperature and light are acknowledged as important factors for hatching of resting eggs. The knowledge of how they affect hatching rates of this type of egg is important for the comprehension of the consequences of warming waters in recolonization of aquatic ecosystems dependent on dormant populations. This study aimed at comparing the influence of different temperature and light conditions on hatching rates of Daphnia ambigua andDaphnia laevis resting eggs from tropical environments. The ephippia were collected in the sediment of three aquatic ecosystems, in southeastern Brazil. For each lake, the resting eggs were exposed to temperatures of 20, 24, 28 and 32 °C, under light (12 h photoperiod and dark conditions. The results showed that the absence of light and high temperatures have a negative influence on the hatching rates. Statistical differences for hatching rates were also found when comparing the studied ecosystems (ranging from 0.6 to 31%, indicating the importance of local environmental factors for diapause and maintenance of active populations.

  12. Studies on improving ostrich egg hatch ability and its relation with some factors affecting embryonic development during artificial incubation

    International Nuclear Information System (INIS)

    Amer, N.S.I.

    2012-01-01

    The present study was carried out in co-operation between the Ostrich Production Farm, Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt and the Faculty of Agriculture, AL-Azhar University, Nasr City, Cairo, Egypt. Ostrich eggs were obtained from Resk Company for Ostrich Production and set for incubation at ElShfie Farm, Belbas, Sharkia, Egypt. The objectives are:1- To follow up changes in some vital physiological parameters and blood components associated with ostrich embryonic development during incubation and to provide reference blood biochemical baseline values for future studies of avian species and to document novel information on some normal changes associated with growth of the developing ostrich embryo during the incubation, as no similar and complete data could be found on this aspect in the literature. 2- In an effort to improve the hatch ability and hatching performance of ostrich eggs by testing the effect of in ovo injection of several nutrients. Two trials were carried out: 1-First trial To follow up changes in some vital physiological parameters and blood components associated with ostrich embryonic development during incubation. A total number of 60 ostrich eggs weighed between 1300 and 1500 g were obtained from from Resk Company for Ostrich Production. Eggs were collected weekly in patches of 25 eggs and Egg incubation was performed in ElShfie Farm, Belbas, Egypt. Egg weight and egg weight loss during incubation were determined on each eggs.2- Second Trial In vivo injection In an effort to improve the hatch ability and hatching performance of ostrich eggs by testing the effect of in ovo injection of several nutrients. A total of 100 fertile ostrich eggs weighed between 1300 and 1500 g were obtained from from Resk Company for Ostrich Production. Eggs were collected weekly in patches of 25 eggs and egg incubation was performed in ElShfie Farm, Belbas, Egypt. Eggs were injected at the 7 th day of incubation to deposit test material in

  13. Pre- and post-hatch trophic egg production in the subsocial burrower bug, Canthophorus niveimarginatus (Heteroptera: Cydnidae)

    Science.gov (United States)

    Filippi, Lisa; Baba, Narumi; Inadomi, Koichi; Yanagi, Takao; Hironaka, Mantaro; Nomakuchi, Shintaro

    2009-02-01

    In recent years, three terrestrial bugs, Adomerus triguttulus and Sehirus cinctus (Cydnidae) and the closely related Parastrachia japonensis (Parastrachiidae), have been the focus of several fascinating studies because of the remarkable, extensive parental care they were found to display. This care includes egg and nymph guarding, production of trophic eggs, unfertilized, low cost eggs that are used as food by newly hatched nymphs, and progressive provisioning of the host seed. In this study, we have investigated yet a third related Asian cydnid, Canthophorus niveimarginatus, with regard to the possible occurrence of some or all of these complex traits in order to assess how widespread these maternal investment patterns are in this group of insects and to better understand the implications of their manifestations from an evolutionary context. Manipulative experiments were carried out in the lab to determine whether females provision nests. Observational and egg removal studies were carried out to determine whether trophic eggs are produced, and, if they are, their possible impact on nymphal success. The findings revealed that C. niveimarginatus does, in fact, progressively provision young, and this species also displays all of the other behaviors associated with extended parental care in subsocial insects. Moreover, unlike the other two related species, which place trophic eggs on the surface of the original egg mass, C. niveimarginatus produces both pre- and post-hatch trophic eggs. Nymphs deprived of access to post-hatch trophic eggs had significantly lower body weight and survival rate than those that fed on them. To our knowledge, this is the first time the production of both pre- and post-hatch trophic eggs has been demonstrated in insects outside the Hymenoptera. In this paper, we qualitatively and quantitatively demonstrate the provisioning behavior and patterns of trophic egg production in C. niveimarginatus. When and how trophic eggs are produced and

  14. Comparing an in vivo egg reduction test and in vitro egg hatching assay for different anthelmintics against Fasciola species, in cattle.

    Science.gov (United States)

    Arafa, Waleed M; Shokeir, Khalid M; Khateib, Abdelrahman M

    2015-11-30

    This study aimed to compare between the efficiency of in vivo fecal egg reduction test (FERT) and in vitro egg hatching assay (EHA) in evaluating of the anti-Fasciola activity of albendazole, triclabendazole, oxyclozanide and praziquantel. A field trial was carried out on fifty naturally Fasciola infected cattle that were divided equally into 5 groups (A-E). On day zero; groups A-D were drenched with albendazole, triclabendazole, oxyclozanide or praziquantel, respectively, while the remaining one, group E, was kept as untreated control. Fecal egg counts of the different groups were conducted weekly over a period of one month post-treatment. In vitro, commercial albendazole and oxyclozanide were diluted to 0.0002, 0.002, 0.02, 0.2 and 2.0 μg/ml, while commercial triclabendazole and praziquantel were diluted to concentrations of 25, 50, 75 and 100 μg/ml with dimethyl sulfoxide (DMSO). In vivo, at the 2nd week post-treatment, triclabendazole and oxyclozanide showed 100% fecal egg reduction (FER), and albendazole had a maximum of 73.7% reduction (P egg counts. In vitro, triclabendazole treated Fasciola gigantica eggs showed early embryonic lysis with zero% hatching at the different concentrations (P egg development and hatching percentage of oxyclozanide or praziquantel treated groups. In conclusion, the efficacy of triclabendazole and albendazole as fasciolicdes could be predicted by Egg Hatching Assay (EHA). Meanwhile fasciolicide activity of oxyclozanide could not be assessed with EHA. Based on in vivo and in vitro findings, paraziquantel did not show any fasciolicide effect. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Evaluation of disinfectants and antiseptics to eliminate bacteria from the surface of turkey eggs and hatch gnotobiotic poults.

    Science.gov (United States)

    Sylte, M J; Chandra, L C; Looft, T

    2017-07-01

    Bird eggs are in contact with intestinal microbiota at or after oviposition, but are protected from bacterial translocation by a glycoprotein cuticle layer, the shell, and internal membranes. In a preliminary study, turkey eggs were hatched in a germ-free environment. Firmicutes 16S rRNA gene was detected in the cecal microbiota of hatched poults, suggesting that poults may acquire spore-formers by exposure to shell contents during hatching. Generating gnotobiotic poults for research requires elimination of bacteria from the egg's surface without damaging the developing embryo. The ability of different disinfectants and antiseptics to eliminate eggshell bacteria without harming the developing embryo was tested. Different classes of disinfectants and antiseptics (halogens, biguanidines, and oxidants) were selected to target spores and vegetative bacteria likely present on the egg's surface. Eggs were treated by fully immersing in heated antiseptic (betadine or chlorhexidine) or disinfectant (alkaline bleach, acidified bleach, chlorine dioxide, Oxysept-333, or Virkon S) solutions for up to 15 minutes. Shells were aseptically harvested for aerobic and anaerobic culturing of bacteria. Toxicity to the developing embryo was assessed by gross evaluation of developmental changes in treated eggs incubated up to 27 d of embryonation. Halogen disinfectants acidified bleach and chlorine dioxide, and oxidants Oxysept-333 and Virkon-S eliminated viable bacteria from eggshells. However, addition of oxidants, alone or in combination with other treatments, produced significant (P eliminated viable bacteria from whole turkey eggs, and produced hatched poults in a gnotobiotic isolator. As a control, eggs were treated with PBS, incubated, and hatched under germ-replete conditions. After hatching, poults were euthanized and treated poults had no detectable bacterial growth or 16S rRNA gene qPCR amplification, demonstrating that acidified sodium hypochlorite, chlorine dioxide, and

  16. When Eggs Don't Hatch. The Benefits of the Sterile Insect Technique

    International Nuclear Information System (INIS)

    Kilian, Lizette

    2012-01-01

    Insect pests, such as the medfly, tsetse flies and carob moth can devastate crops and infect herds, causing severe economic hardship. To suppress the insect pest population and protect their livestock and crops, farmers usually use large quantities of pesticides. However, these pesticides are expensive, a risk to public health and cause environmental damage. Another technique, however, can reduce the insect pest population using natural means that do not require toxic chemicals: the sterile insect technique, or SIT. When female insect pests mate with male partners that have been radiation sterilized, the insemination produces eggs that cannot hatch. Since mating does not produce offspring, the insect population decreases naturally. The pest population can be suppressed with little or no use of pesticides. With the help of the IAEA, farmers have applied SIT successfully in over 20 countries on five continents, for over 15 insect species worldwide.

  17. Effect of brood size and hatching sequence on prefledging mortality of Sandwich terns: why lay two eggs?

    NARCIS (Netherlands)

    Stienen, E.W.M.; Brenninkmeijer, A.

    2006-01-01

    The mortality of Sandwich tern Sterna sandvicensis chicks held in enclosures was studied in colonies on Griend, in the Dutch Wadden Sea, from 1992 to 1999, and on Hirsholm, in the Danish Kattegat, in 1997. Survival of chicks until fledging was 73% for chicks hatching from first-laid eggs or

  18. Effect of brood size and hatching sequence on prefledging mortality of Sandwich terns : why lay two eggs?

    NARCIS (Netherlands)

    Stienen, Eric W. M.; Brenninkmeijer, Alex

    2006-01-01

    The mortality of Sandwich tern Sterna sandvicensis chicks held in enclosures was studied in colonies on Griend, in the Dutch Wadden Sea, from 1992 to 1999, and on Hirsholm, in the Danish Kattegat, in 1997. Survival of chicks until fledging was 73% for chicks hatching from first-laid eggs or

  19. Recovery of salmonella serovar enteritidis from inoculated broiler hatching eggs using shell rinse and shell crush sampling methods

    Science.gov (United States)

    This study compared the recovery of Salmonella from hatching eggs using three sampling methods (eggshell rinsing, eggshell crush following a previous rinse, and eggshell crush without previous rinse). Eggshells were drop-inoculated with approximately 10, 100, or 1,000 cfu/eggshell of S. Enteritidis...

  20. Influence of natural inshore and offshore thermal regimes on egg development and time of hatch in American lobsters, Homarus americanus.

    Science.gov (United States)

    Goldstein, Jason S; Watson, Winsor H

    2015-02-01

    Some egg-bearing (ovigerous) American lobsters (Homarus americanus) make seasonal inshore-to-offshore movements, subjecting their eggs to different thermal regimes than those of eggs carried by lobsters that do not make these movements. Our goal was to determine if differences in thermal regimes influence the rate of egg development and the subsequent time of hatch. We subjected ovigerous lobsters to typical inshore or offshore water temperatures from September to August in the laboratory (n=8 inshore and 8 offshore, each year) and in the field (n=8 each, inshore and offshore), over 2 successive years. Although the rate of egg development did not differ significantly between treatments in the fall (P∼0.570), eggs exposed to inshore thermal regimes developed faster in the spring (Plobsters exposed to offshore thermal regimes accumulated more GDD in the winter than did eggs carried by inshore lobsters, while eggs exposed to inshore temperatures acquired them more rapidly in the spring. Results suggest that seasonal movements of ovigerous lobsters influence the time and location of hatching, and thus the transport and recruitment of larvae to coastal and offshore locations. © 2015 Marine Biological Laboratory.

  1. Reproductive behavior and physiology of Dacus oleae: egg hatch in females mated successively with normal and gamma sterilized males and vice versa

    International Nuclear Information System (INIS)

    Economopoulos, A.P.; Giannakakis, A.; Voyadjoglou, A.V.

    1976-01-01

    In Dacus oleae (Gmelin), a 2nd mating by an 8-krad gamma ray-sterilized male reduced egg hatch immediately to zero or near-zero in ca. 40-55 percent of individually-tested females. In another 50 percent of females, egg hatch was reduced to between 5 to 70 percent, while in fewer than 10 percent of females, egg hatch showed no change. The above was true for females reared on artificial diet for more than 50 generations and mated with same type males, as well as females reared on olives for 6 to 8 generations and mated first with same type males and 2nd with artificially-reared sterilized males. When the 2nd males were treated at 15 krad the effect on egg hatch was smaller. When the 2nd males were treated at 8 krad and had depleted their sperm, by repeated matings, they produced small or no-effect on egg hatch. When artificially-reared females mated first with a sterilized and second with a normal same type male, egg hatch increased from 0 to 5 percent to 70 to 100 percent in 50 to 55 percent of the cases. In another 43 percent of cases, egg hatch increased to levels between 5 to 70 percent. The combined findings from the 2 mating sequence types are as follows. After females mated first with normal males, egg hatch was above 80 percent in the population; a 2nd mating with 8-krad-sterilized males produced an immediate decrease of egg hatch to ca. 25 percent, decreasing slowly thereafter. When the 1st male was sterilized and the 2nd normal, egg hatch increased to ca. 70 percent, decreasing slowly thereafter

  2. Concentration of total proteins in blood plasma of chickens hatched from irradiated eggs with low dose gamma radiation

    International Nuclear Information System (INIS)

    Vilic, M.; Kraljevic, P.; Miljanic, S.; Simpraga, M.

    2005-01-01

    It is known that low-dose ionising radiation may have stimulating effects on chickens. Low doses may also cause changes in the concentration of blood plasma total proteins, glucose and cholesterol in chickens. This study investigates the effects of low dose gamma-radiation on the concentration of total proteins in the blood plasma of chickens hatched from eggs irradiated with a dose of 0.15 Gy on incubation days 7 and 19. Results were compared with the control group (chickens hatched from non-irradiated eggs). After hatching, all other conditions were the same for both groups. Blood samples were drawn from the heart, and later from the wing vein on days 1, 3, 5, 7,10, 20, 30 and 42. The concentration of total proteins was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. The concentration of total proteins in blood plasma in chickens hatched from eggs irradiated with 0.15 Gy on incubation day 7 showed a statistically significant decrease on the sampling day 3 (P less than 0.05) and 7 (P less than 0.01). The concentration of total proteins in blood plasma in chickens hatched from eggs irradiated with 0.15 Gy on incubation day 19 showed a statistically significant increase only on sampling day 1 (P less than 0.05). These results suggest that exposure of eggs to 0.15 Gy of gamma-radiation on the 7th and 19th day of incubation could produce different effects on the protein metabolism in chickens.(author)

  3. Discrimination of gastrointestinal nematode eggs from crude fecal egg preparations by inhibitor-resistant conventional and real-time PCR.

    Directory of Open Access Journals (Sweden)

    Janina Demeler

    Full Text Available Diagnosis of gastrointestinal nematodes relies predominantly on coproscopic methods such as flotation, Kato-Katz, McMaster or FLOTAC. Although FLOTAC allows accurate quantification, many nematode eggs can only be differentiated to genus or family level. Several molecular diagnostic tools discriminating closely related species suffer from high costs for DNA isolation from feces and limited sensitivity since most kits use only small amounts of feces (<1 g. A direct PCR from crude egg preparations was designed for full compatibility with FLOTAC to accurately quantify eggs per gram feces (epg and determine species composition. Eggs were recovered from the flotation solution and concentrated by sieving. Lysis was achieved by repeated boiling and freezing cycles - only Trichuris eggs required additional mechanic disruption. Egg lysates were directly used as template for PCR with Phusion DNA polymerase which is particularly resistant to PCR inhibitors. Qualitative results were obtained with feces of goats, cattle, horses, swine, cats, dogs and mice. The finally established protocol was also compatible with quantitative real-time PCR in the presence of EvaGreen and no PCR inhibition was detectable when extracts were diluted at least fourfold. Sensitivity was comparable to DNA isolation protocols and spiked samples with five epg were reliably detected. For Toxocara cati a detection limit below one epg was demonstrated. It was possible to distinguish T. cati and Toxocara canis using high resolution melt (HRM analysis, a rapid tool for species identification. In human samples, restriction fragment length polymorphism (RFLP and HRM analysis were used to discriminate Necator americanus and Ancylostoma duodenale. The method is able to significantly improve molecular diagnosis of gastrointestinal nematodes by increasing speed and sensitivity while decreasing overall costs. For identification of species or resistance alleles, analysis of PCR products with many

  4. Discrimination of gastrointestinal nematode eggs from crude fecal egg preparations by inhibitor-resistant conventional and real-time PCR.

    Science.gov (United States)

    Demeler, Janina; Ramünke, Sabrina; Wolken, Sonja; Ianiello, Davide; Rinaldi, Laura; Gahutu, Jean Bosco; Cringoli, Giuseppe; von Samson-Himmelstjerna, Georg; Krücken, Jürgen

    2013-01-01

    Diagnosis of gastrointestinal nematodes relies predominantly on coproscopic methods such as flotation, Kato-Katz, McMaster or FLOTAC. Although FLOTAC allows accurate quantification, many nematode eggs can only be differentiated to genus or family level. Several molecular diagnostic tools discriminating closely related species suffer from high costs for DNA isolation from feces and limited sensitivity since most kits use only small amounts of feces (PCR from crude egg preparations was designed for full compatibility with FLOTAC to accurately quantify eggs per gram feces (epg) and determine species composition. Eggs were recovered from the flotation solution and concentrated by sieving. Lysis was achieved by repeated boiling and freezing cycles - only Trichuris eggs required additional mechanic disruption. Egg lysates were directly used as template for PCR with Phusion DNA polymerase which is particularly resistant to PCR inhibitors. Qualitative results were obtained with feces of goats, cattle, horses, swine, cats, dogs and mice. The finally established protocol was also compatible with quantitative real-time PCR in the presence of EvaGreen and no PCR inhibition was detectable when extracts were diluted at least fourfold. Sensitivity was comparable to DNA isolation protocols and spiked samples with five epg were reliably detected. For Toxocara cati a detection limit below one epg was demonstrated. It was possible to distinguish T. cati and Toxocara canis using high resolution melt (HRM) analysis, a rapid tool for species identification. In human samples, restriction fragment length polymorphism (RFLP) and HRM analysis were used to discriminate Necator americanus and Ancylostoma duodenale. The method is able to significantly improve molecular diagnosis of gastrointestinal nematodes by increasing speed and sensitivity while decreasing overall costs. For identification of species or resistance alleles, analysis of PCR products with many different post PCR methods can

  5. Effect of temperature on incubation period, embryonic mortality, hatch rate, egg water loss and partridge chick weight (Rhynchotus rufescens

    Directory of Open Access Journals (Sweden)

    Nakage ES

    2003-01-01

    Full Text Available The aim of this study was to determine the effects of incubation temperature (34.5; 35.5; 36.5; 37.5 and 38.5ºC, on incubation period, embryonic mortality, hatching rate, water loss and chick weight at hatch, using daily incubation of partridge (Rhynchotus rufescens eggs. The highest hatching percentage was obtained between 35.5 and 36.5ºC. Incubation length and temperature were inversely proportional. Water loss was lower in eggs incubated at low temperatures as compared to high temperatures. There was no difference among incubation temperatures in absolute and relative hatchling weights. Early embryonic mortality increased at low temperatures (36.5ºC. Our results show that, under conditions of daily incubation of eggs in the same incubator, higher hatching rate can be obtained using temperatures between 35.5ºC and 36.5ºC; incubation temperature is inversely proportional to incubation length, and absolute and relative weights of partridge chicks are not affected by incubation temperature.

  6. Entrainment of the Circadian Rhythm in Egg Hatching of the Crab Dyspanopeus sayi by Chemical Cues from Ovigerous Females.

    Science.gov (United States)

    Forward, Richard B; Sanchez, Kevin G; Riley, Paul P

    2016-02-01

    The subtidal crab Dyspanopeus sayi has a circadian rhythm in larval release with a free-running period of 24.1 h. Under constant conditions, eggs hatch primarily in the 4-h interval after the time of sunset. The study tested the new model for entrainment in subtidal crabs, which proposes that the female perceives the environmental cycles and entrains the endogenous rhythm in the embryos. Results verified the model for D. sayi. Hatching by embryos collected from the field when they had not yet developed eye pigments, and were kept in constant conditions attached to their mother, exhibited the circadian hatching rhythm. Attached embryos could also be entrained to a new photoperiod in the laboratory before they developed eye pigments. Further, mature embryos removed from the female hatched rhythmically, indicating that a circadian rhythm resides in the embryos. However, if mature embryos with eye pigments were removed from the female and exposed to a new light-dark cycle, they could not be entrained to the new cycle; rather, they hatched according to the timing of the original light-dark cycle. Nevertheless, detached, mature embryos would entrain to a new light-dark cycle if they were in chemical, but not physical, contact with the female. Thus, the female perceives the light-dark cycle, and uses chemical cues to entrain the circadian rhythm of hatching by the embryos. © 2016 Marine Biological Laboratory.

  7. Effects of egg incubation condition on the post-hatching growth and performance of the snapping turtle, Chelydra serpentina

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, Kathleen M. [State Univ. of New York (SUNY),Buffalo, NY (United States)

    1990-12-01

    The effect of incubation temperature on the post-hatching growth and performance capacities of the common snapping turtle, Chelydra serpentina was investigated in the laboratory. Turtle eggs were collected from four sites in New York State and randomly assigned to four incubation temperature treatments to produce males (constant 26°C and downshifted 30-26-30°C) and females (constant 30°C and upshifted 26-30-26°C) under constant and altered temperature regimes. The incubation conditions resulted in 92% males from the constant 26°C group and 93% males from the downshifted group. 100% females resulted from both the constant 30°C group and the upshifted group. Turtles hatching from eggs incubated constantly at 26°C were significantly larger than hatchlings from eggs incubated at a constant 30°C or downshifted. Hatchlings were raised in individual aquaria at 25°C and fed earthworms and fish. After a 9-month growth period, turtles which had been incubated at a constant 30°C gained significantly more mass than did turtles from eggs which had been downshifted or upshifted. There was no extended effect of incubation condition on Post-hatching performance and learning ability as measured by righting and feeding responses. Thus, the mass gain differences seen in this study suggest that physiological differences do result as the consequence of incubation condition. However, these physiological differences are not reflected in normal locomotive or feeding behavior.

  8. Effects of egg incubation condition on the post-hatching growth and performance of the snapping turtle, Chelydra serpentina

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, K.M.

    1990-12-01

    The effect of incubation temperature on the post-hatching growth and performance capacities of the common snapping turtle, Chelydra serpentina was investigated in the laboratory. Turtle eggs were collected from four sites in New York State and randomly assigned to four incubation temperature treatments to produce males (constant 26[degree]C and downshifted 30-26-30[degree]C) and females (constant 30[degree]C and upshifted 26-30-26[degree]C) under constant and altered temperature regimes. The incubation conditions resulted in 92% males from the constant 26[degree]C group and 93% males from the downshifted group. 100% females resulted from both the constant 30[degree]C group and the upshifted group. Turtles hatching from eggs incubated constantly at 26[degree]C were significantly larger than hatchlings from eggs incubated at a constant 30[degree]C or downshifted. Hatchlings were raised in individual aquaria at 25[degree]C and fed earthworms and fish. After a 9-month growth period, turtles which had been incubated at a constant 30[degree]C gained significantly more mass than did turtles from eggs which had been downshifted or upshifted. There was no extended effect of incubation condition on Post-hatching performance and learning ability as measured by righting and feeding responses. Thus, the mass gain differences seen in this study suggest that physiological differences do result as the consequence of incubation condition. However, these physiological differences are not reflected in normal locomotive or feeding behavior.

  9. Chemical composition and efficacy in the egg-hatching inhibition of essential oil of Piper aduncum against Haemonchus contortus from sheep

    Directory of Open Access Journals (Sweden)

    Gisele Lopes Oliveira

    Full Text Available Piper aduncum L., Piperaceae, has been used to treat mainly inflammatory diseases and has shown several biological activities such as insecticidal and larvicidal. The aim of this study was to analyze the chemical composition of essential oil of P. aduncum and its efficacy to egg-hatching inhibition of Haemonchus contortus from sheep. The essential oil was obtained from leaves and analysed by gas chromatography coupled to flame ionization detector and gas chromatography coupled to mass spectrometry. It was possible to characterize 22 different substances, among them monoterpenes (80.6% and sesquiterpenes (13.9%. The major compound was identified as 1,8-cineole (55.8%. Eggs of the nematode were exposed to four concentrations of the essential oil. Levamisole phosphate was used as positive control. The essential oil showed to be effective in inhibiting H. contortus hatchability and the LC90 was calculated as 8.9 mg.ml-1. These results can point out the P. aduncumessential oil and its chemical components as potential alternative to control of H. contortus

  10. Quantitative characterization of texture used for identification of eggs of bovine parasitic nematodes

    DEFF Research Database (Denmark)

    Sommer, C.

    1998-01-01

    This study investigates the use of texture, i.e. the grey level variation in digital images, as a basis for identification of strongylid eggs. Texture features were defined by algorithms applied to digital images of eggs from the bovine parasitic nematodes, Ostertagia ostertagi, Cooperia oncophora...... criterion based on these ten texture features, an average of 91.2% of eggs from the three species were correctly classified. All O. radiatum eggs were correctly classified, 11.8% of O. ostertagi and C. oncophora were reciprocally misclassified, and 2.9% of O. ostertagi were identified as O. radiatum. When...... the ten texture features were used singly an average of 51.2 to 37.9% of the species could be classified correctly. When texture was used together with the shape and size features, a higher percentage of eggs were correctly classified compared with the classification based on either texture, or shape...

  11. Information needs, sources, and decision-making by hatching egg and broiler chicken producers: A qualitative study in Alberta, Canada.

    Science.gov (United States)

    Anholt, R Michele; Russell, Margaret; Inglis, Tom; Mitevski, Darko; Hall, David

    2017-05-01

    Understanding the sources and use of information from hatching egg and broiler chicken producers, their constraints, and unmet information needs can help define future research agendas. This report presents the results from a qualitative study using interviews of 11 hatching egg producers and 12 broiler producers in Alberta, Canada. Patterns were reported and described using thematic analysis. Producers recognized that there were numerous sources of information available to them for managing disease in their flocks. Complex disease issues such as early mortality were discussed, but many producers did not believe they had any influence over the outcomes and did not see a benefit from additional information to improve outcomes. Producers described their experience, trust in the information source, and the usefulness of the information for decision-making as necessary for information uptake.

  12. The Biophysical Characteristics Of Hatching Habitat Of Lekang Turtle (Lepidhochelys olivacea) Eggs In Turtle Conservation And Education Center, Bali

    Science.gov (United States)

    Suryono; Ario, R.; Wibowo, E.; Handoyo, G.

    2018-02-01

    Lekang turtle (Lepidhochelys olivacea) is one of the fauna that is protected as an endangered population. This marine reptile was able to migrate in great distance along the Indian Ocean, the Pacific Ocean, and South East Asia. Its existence has long been threatened, either by nature or human activities that endangered the population directly or indirectly. The decreasing number of sea turtle population that nest in Bali area is one indication of the reducing number of Lekang turtle in Indonesia. If left unchecked, it will result in the loss of Lekang turtle. This study aims to determine the successful percentage of conservation techniques and Lekang turtle hatching eggs (olive ridley sea turtle) in TCEC, Bali. The method used in this research is the method of observation or direct observation done in the field. Data collection is done by direct observation in the field. The results showed that the turtle breeding site is located in an area that is less strategic because too far from the sea, so that the temperature and humidity cannot be stable. Water content is most an important factor in the growth of embryo and egg hatching. This will lead to the decrease of hatching percentage of turtle eggs.

  13. Effect of Linear Alkylbenzene Sulfonate on Mortality, Hatching Rate of Eggs and Abnormality of Catfish (Pangasius hypophthalmus Sauvage Larvae

    Directory of Open Access Journals (Sweden)

    E. Supriyono

    2007-01-01

    Full Text Available Linear alkylbenzene sulfonate (LAS surfactant in the water can affecting fish in all developmental stages.  This study was aimed to observe the effect of LAS on mortality, hatching rate of eggs, and abnormality of patin catfish (Pangasius hypophthalmus Sauvage larvae.   Fertilized eggs were incubated in water containing LAS at the dosages of 0.0, 0.5, 1.5, 3.0, 9.0, and 18.0 mg/L.  Eggs mortality was observed every 6 hours until larvae hatched (24 hours.  The results of study showed that the exposure of 18.0 mg LAS per liter water could put to death all the fertilized eggs and larvae be abnormal.  The exposure of LAS at concentration of 9.0 mg/L could kill 98% of eggs and hatching rate was only 2%.  The abnormality in larvae was bending in the body and tails. Keywords: patin catfish, Pangasius, Linear Alkylbenzene Sulfonate, LAS, abnormality   ABSTRAK Surfaktan Linear Alkylbenzene Sulfonate (LAS yang masuk ke dalam perairan sangat berpengaruh terhadap ikan dari stadia awal hidup ikan sampai dewasa. Penelitian ini bertujuan untuk mengetahui pengaruh LAS terhadap mortalitas, daya tetas telur dan abnormalitas larva ikan patin (Pangasius hypophthalmus Sauvage.  Telur ikan patin yang telah dibuahi di rendam dalam air yang mengandung LAS dengan konsentrasi 0,0; 0,5; 1,5; 3,0; 9,0 dan 18,0 mg/L.  Mortalitas telur dicatat setiap 6 jam sampai menetas (24 jam.  Hasil penelitian menunjukkan bahwa konsentrasi LAS sebesar 18,0 mg/L dapat mengakibatkan mortalitas telur dan abnormalitas pada larva secara total.  Konsentrasi LAS sebesar 9,0 mg/L dapat mematikan telur hingga 98% dan hanya menghasilkan daya tetas sebanyak 2%. Abnormalitas pada larva berupa pembengkokan pada tubuh dan ekor. Kata kunci: ikan patin, Pangasius, Linear Alkylbenzene Sulfonate, LAS dan abnormalitas

  14. Successful hatching from eggs carried by females and naturally removed from incubant males in Belostoma spp. water bugs (Heteroptera: Belostomatidae

    Directory of Open Access Journals (Sweden)

    Ana Lía Estévez

    2006-06-01

    Full Text Available Within Belostomatinae water bug species (Heteroptera, Belostomatidae it has been hitherto believed that the completion of embryonic development is successful only if eggs are incubated on male hemelytra. Nevertheless, we found egg successful hatching from a back- brooding Belostoma elegans (Mayr and B. micantulum (Stål females, as well as from fertilized eggs kicked off from four back-brooder B. elegans males. One "encumbered" B. elongatum Montandon female was also recorded, but eggs did not hatch after she removed them. Rev. Biol. Trop. 54(2: 515-517. Epub 2006 Jun 01.Se considera que el desarrollo embrionario y la emergencia de las ninfas de las especies de Belostomatinae (Heteroptera, Belostomatidae se cumplen con éxito si los huevos son incubados sobre el espacio dorsal de machos adultos. No obstante, hemos registrado eclosiones exitosas a partir de dos hembras grávidas portando huevos sobre su dorso; una de ellas de la especie Belostoma elegans (Mayr, la otra de B. micantulum (Stål. Se registra la eclosión de huevos, previamente removidos del área de postura por los propios machos incubantes de B. elegans (N=4 y la presencia de una hembra de B. elongatum Montandon, portando huevos sobre sus hemiélitros, los cuales no eclosionaron después de haber sido removidos por la propia hembra.

  15. Prevalence of nematode infection and faecal egg counts in free-range laying hens: relations to housing and husbandry.

    Science.gov (United States)

    Sherwin, C M; Nasr, M A F; Gale, E; Petek, M; Stafford, K; Turp, M; Coles, G C

    2013-01-01

    1. Faecal samples from 19 commercial, 65 week old free-range egg laying flocks were examined to assess the prevalence and number of parasitic nematode eggs. Data were collected to characterise the housing, husbandry, behaviour and welfare of the flocks to examine possible relationships with the egg counts. 2. Eggs of at least one genus of nematode were present in the faeces of all 19 flocks. Heterakis eggs were detected in 17 (89%) flocks, Ascaridia in 16 (84%), Trichostrongylus in 9 (47%), and Syngamus in 6 (32%). Faecal egg counts (FEC) were greatest for Ascaridia and Heterakis. 3. For each nematode genus, there was no significant difference in FEC between organic (N = 9) and non-organic (N = 10) flocks, or between static (N = 8) and mobile (N = 11) flocks. 4. FEC were correlated with a range of housing, husbandry and management practices which varied between the nematode genus and included depth of the litter, percentage of hens using the range, and number of dead hens. Statistical analysis indicated relationships with FEC that included light intensity above the feeder, indoor and outdoor stocking density, fearfulness in the shed and on the range, distance to the nearest shelter, and swollen toes. 5. None of the FEC for any of the genera was correlated with weekly egg production or cumulative mortality. 6. Although nematode FEC were highly prevalent among the flocks, the overall lack of relation to other welfare and production measures suggests that these infections were not severe.

  16. Inheritance and world variation in thermal requirements for egg hatch in Lymantria dispar (Lepidoptera: Erebidae)

    Science.gov (United States)

    M.A. Keena

    2016-01-01

    Mode of inheritance of hatch traits in Lymantria dispar L. was determined by crossing populations nearly fixed for the phenotypic extremes. The nondiapausing phenotype was inherited via a single recessive gene and the phenotype with reduced low temperature exposure requirements before hatch was inherited via a single dominant gene. There was no...

  17. Presence of antimicrobial resistance in coliform bacteria from hatching broiler eggs with emphasis on ESBL/AmpC-producing bacteria.

    Science.gov (United States)

    Mezhoud, H; Chantziaras, I; Iguer-Ouada, M; Moula, N; Garmyn, A; Martel, A; Touati, A; Smet, A; Haesebrouck, F; Boyen, F

    2016-08-01

    Antimicrobial resistance is recognized as one of the most important global health challenges. Broilers are an important reservoir of antimicrobial resistant bacteria in general and, more particularly, extended-spectrum β-lactamases (ESBL)/AmpC-producing Enterobacteriaceae. Since contamination of 1-day-old chicks is a potential risk factor for the introduction of antimicrobial resistant Enterobacteriaceae in the broiler production chain, the presence of antimicrobial resistant coliform bacteria in broiler hatching eggs was explored in the present study. Samples from 186 hatching eggs, collected from 11 broiler breeder farms, were inoculated on MacConkey agar with or without ceftiofur and investigated for the presence of antimicrobial resistant lactose-positive Enterobacteriaceae, particularly, ESBL/AmpC-producers. Escherichia coli and Enterobacter cloacae were obtained from the eggshells in 10 out of 11 (10/11) sampled farms. The majority of the isolates were recovered from crushed eggshells after external decontamination suggesting that these bacteria are concealed from the disinfectants in the egg shell pores. Antimicrobial resistance testing revealed that approximately 30% of the isolates showed resistance to ampicillin, tetracycline, trimethoprim and sulphonamides, while the majority of isolates were susceptible to amoxicillin-clavulanic acid, nitrofurantoin, aminoglycosides, florfenicol, neomycin and apramycin. Resistance to extended-spectrum cephalosporins was detected in eight Enterobacteriaceae isolates from five different broiler breeder farms. The ESBL phenotype was confirmed by the double disk synergy test and blaSHV-12, blaTEM-52 and blaACT-39 resistance genes were detected by PCR. This report is the first to present broiler hatching eggs as carriers and a potential source of ESBL/AmpC-producing Enterobacteriaceae for broiler chicks.

  18. Effects of catechins and low temperature on embryonic development and hatching in Heterodera glycines and Meloidogyne incognita

    Science.gov (United States)

    Mimics of two natural influences, a chemical similar to one present in cyst nematodes and low temperature exposure of nematode eggs, were evaluated for their effects on quantitative and qualitative features of embryonic development and hatching. The polyphenol epigallocatechin gallate (EGCG), an ana...

  19. Effects of γ-rays on hatching of the eggs and survival period of the fry of Cyprinus carpio

    International Nuclear Information System (INIS)

    Shrivastava, R.S.; Dwivedi, P.

    1980-01-01

    Eggs of the common carp, Cyprinus carpio, were exposed to 0.0258, 0.129, 0.258, 0.516, and 1.29 C/kg, respectively, 60 Co γ-radiation. The time between spawning and hatching of the fry was 48 to 56 hours compared to 72 to 79 hours in the untreated controls. With increasing exposure the hatching rates were 36, 24, 28, 30 and 34%; the survival periods were 11, 9, 8, 7 and 6 days and the 50% mortality period was 8, 7, 6, 4 and 4 days, respectively. With increasing radiation doses the fry exhibited increasing deformations of the body, especially of the postanal region, as well as unbalanced movements

  20. Latex constituents from Calotropis procera (R. Br. display toxicity upon egg hatching and larvae of Aedes aegypti (Linn.

    Directory of Open Access Journals (Sweden)

    Márcio Viana Ramos

    2006-08-01

    Full Text Available Calotropis procera R. Br. (Asclepiadaceae is a well-known medicinal plant with leaves, roots, and bark being exploited by popular medicine to fight many human and animal diseases. This work deals with the fractionation of the crude latex produced by the green parts of the plant and aims to evaluate its toxic effects upon egg hatching and larval development of Aedes aegypti. The whole latex was shown to cause 100% mortality of 3rd instars within 5 min. It was fractionated into water-soluble dialyzable (DF and non-dialyzable (NDF rubber-free materials. Both fractions were partially effective to prevent egg hatching and most of individuals growing under experimental conditions died before reaching 2nd instars or stayed in 1st instars. Besides, the fractions were very toxic to 3rd instars causing 100% mortality within 24 h. When both fractions were submitted to heat-treatment the toxic effects were diminished considerably suggesting low thermostability of the toxic compounds. Polyacrylamide gel electrophoresis of both fractions and their newly fractionated peaks obtained through ion exchange chromatography or desalting attested the presence of proteins in both materials. When submitted to protease digestion prior to larvicidal assays NDF lost most of its toxicity but DF was still strongly active. It may be possible that the highly toxic effects of the whole latex from C. procera upon egg hatching and larvae development should be at least in part due to its protein content found in NDF. However the toxicity seems also to involve non protein molecules present in DF.

  1. Egg production and hatching success of Paracartia grani (Copepoda, Calanoida, Acartiidae) in two hypersaline ponds of a Tunisian Solar Saltern

    Science.gov (United States)

    Annabi-Trabelsi, Neila; Rebai, Rayda Kobbi; Ali, Mohammad; Subrahmanyam, M. N. V.; Belmonte, Genuario; Ayadi, Habib

    2018-04-01

    Reproductive traits of Paracartia grani [percentage of spawning females, egg production rate (EPR), and hatching success (HS)] were investigated for the first time at high salinities (39-121 psu) to examine the impact of such a particular situation. The study was done in two hypersaline ponds [A1 (39-46 psu) and C31 (70-121 psu)] in Sfax Solar Saltern, central-eastern coast of Tunisia. These ponds also differed in terms of the composition and concentrations of nutritional parameters. The EPR differed significantly between the ponds (ANOVA, F = 29.45, p eggs female- 1 day- 1 (7 December 2009) and 14 ± 1 eggs female- 1 day- 1 (19 January 2010) with an average of 13.3 ± 0.44 eggs female- 1 day- 1. HS after 48 h of incubation were significantly higher than those after 24 h. The mean values of HS after 48 h were 42.72 ± 2.58% at pond A1 and 41.67 ± 3.92% at pond C31. The two peaks of HS (after 48 h) were observed at 15 °C in pond A1 (21 December 2009, 45.18% nauplii eggs- 1) and in C31 (4 January 2010, 48.78%) at the same temperature. This study confirms that a broad salinity tolerance allows P. grani to settle itself in environments, which are normally hostile to the development of other Acartiidae.

  2. Advanced Oxidation Process sanitation of hatching eggs reduces Salmonella in broiler chicks

    Science.gov (United States)

    Reduction of Salmonella contamination of eggs is important in improving the microbial food safety of poultry and poultry products. Developing interventions to reduce Salmonella contamination of eggs is important to improving the microbial quality of eggs entering the hatchery. Previously, the hydr...

  3. Storage of Hatching Eggs : Effects of storage and early incubation conditions on egg characteristics, embryonic development, hatchability, and chicken quality

    NARCIS (Netherlands)

    Reijrink, I.A.M.

    2010-01-01

    Key words: egg storage, embryonic development, albumen quality, hatchability, chick quality

    It is well known that an increase in the storage duration increases incubation duration and decreases hatchability and chick quality. The negative effects of prolonged egg storage (> 7 days)

  4. 9 CFR 82.8 - Interstate movement of eggs, other than hatching eggs, from a quarantined area.

    Science.gov (United States)

    2010-01-01

    ... arrival of the eggs at the facility. (b) Any flats or cases intended for reuse after being used to move... part 71 of this chapter before being moved to a premises where birds or poultry are kept. [61 FR 56883... be moved interstate from a quarantined area only if: (1) The eggs are accompanied by a permit...

  5. Possible presence of common tyvelose-containing glycans in Trichinella L1 larvae and embryonated eggs of several nematodes

    Directory of Open Access Journals (Sweden)

    Dea-Ayuela M.A.

    2001-06-01

    Full Text Available A monoclonal antibody (mAb US4 recognising an epitope containing tyvelose within the T. spiralis L-1 muscle larvae (TSL-1 antigens was tested in western-blot against various antigenic preparations from different stages of the following nematodes: T. spiralis (L1,adult, T. muris (egg, L1, L3, adult, Ascaris suum (egg, adult, Toxocara canis (egg, adult, Anisakis simplex (L3 and Haemochus contortus (egg. Positive reaction was present in antigen preparations from L1 larvae of T. spiralis and T. muris and from embryonated eggs of T. muris, A. suum, T. canis and H. conlortus.

  6. Effect of Low Dose Gamma Radiation Upon Phosphatase Activity in Blood Plasma of Chicken Hatched from Eggs Irradiated on the Seventh Day of Incubation

    International Nuclear Information System (INIS)

    Kraljevic, P.; Vilic, M.; Miljanic, S.; Simpraga, M.

    2008-01-01

    In our earlier studies chickens hatched from eggs irradiated with 0.15 Gy gamma rays before incubation showed a significantly higher growth than controls during the fattening period (1-42 days). The activity of aspartate-aminotransferase (AST), alanine-aminotransferase (ALT), acid phosphatase (ACP) and plasma glucose in the same chickens were also significantly higher. These results suggested that low-dose gamma-radiation stimulated certain metabolic processes in chickens hatched from eggs irradiated before incubation. Investigating the effect of low dose gamma radiation upon transferases activity in blood plasma of chickens hatched from eggs irradiated on the 7th day of incubation, i.e. in the time when organogenesis is completely finished, we found that on day 10, AST and ALT activity was significantly higher in the blood plasma of those chickens, whereas it significantly dropped for both enzymes on day 20. This time the goal of study was to determine the effect of low-dose gamma radiation on ACP and alkaline phosphatase (ALP) activity in the blood plasma of chickens hatched from eggs irradiated on the 7th day of incubation. The eggs of heavy breeding chickens (Avian, line 34) were exposed to 0.15 Gy of gamma radiation (60Co) on the seventh day of incubation. The control group included chickens hatched from non-irradiated eggs. All other conditions were the same for both groups. After hatching, blood samples were taken from the wing vein on days 1, 3, 5, 7, 10, 20, 32 and 42. The activity of both enzymes was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. ACP activity was significantly lower in the blood plasma of chickens hatched from irradiated eggs on day 3 (P<0,01), 5 (P<0,05) and 10 (P<0,05). Throughout the experimental period ALP activity did not statistically significantly change. Our results indicate that exposure of eggs to low-dose gamma radiation on the seventh day of incubation reduces ACP activity in the blood plasma

  7. Broiler performance, hatching egg, and age relationships of progeny from standard and dwarf broiler dams.

    Science.gov (United States)

    Tahir, M; Cervantes, H; Farmer, C W; Shim, M Y; Pesti, G M

    2011-06-01

    The relationship of egg and chick weights to the performance of broiler chickens from two 42-wk-old flocks (standard and dwarf dams) having male parents from the same genetic stock was investigated in this study. Fertility (91.7 vs. 94.7%) and hatchability (95.2 vs. 96.3%) were not significantly (P > 0.10) different for eggs from standard and dwarf dams, respectively. Egg weight contributed significantly to the variation in BW [BW = β(0) + β(i) (egg weight) + β(i) (dam) + β(i) (sex)]. Body weight as a function of chick weight was not significant. However, chick weight was significant when included in a model with egg weight, suggesting that significant differences in BW at 50 d could be attributed to both egg and chick weights. The negative coefficient for chick weight indicated that between the 2 broilers of the same egg weight, the one with the greater chick weight would have the smaller 50-d BW. Chick weight was a linear function of egg weight. Similarly, the effect of egg or chick weight on broiler BW at 35 or 50 d was best represented by a single linear function. Dam genotype did not contribute significantly to variation in 50-d BW after variation attributable to egg weight was removed from the model. Differences in BW attributable to egg weight increased with broiler age. The coefficients of egg weight and chick weight showed that the differences in BW per gram of egg were 1.43, 3.06, 6.24, and 7.61 g and those per gram of chick were 1.87, 3.99, 8.14, and 9.93 g, respectively, at 7, 21, 35, and 50 d. Body weight increased by 0.1563 times egg weight (and 0.2092 times chick weight) with each additional day of age for both sexes and genotypes. Clearly, both egg and chick weights are important for modeling or predicting market-age broiler BW and economic returns. The relatively small relationship between BW and egg weight demonstrates that genetic selection over the past 3 decades has decreased the influence of egg weight on broiler growth. The present dwarf

  8. Effect of temperature and salinity on egg hatching and description of the life cycle of Lernanthropus latis (Copepoda: Lernanthropidae) infecting barramundi, Lates calcarifer.

    Science.gov (United States)

    Brazenor, Alexander K; Hutson, Kate S

    2013-10-01

    The parasite Lernanthropus latis (Copepoda: Lernanthropidae) is a major threat to the sustained mariculture of barramundi, Lates calcarifer (Perciformes: Latidae). We investigated the effect of water temperature and salinity on egg hatching success of L. latis and describe the life cycle for the first time. Wild and sea-caged L. calcarifer examined in tropical north Australia exhibited similar parasite prevalence (range: 80-100%) and mean parasite intensity (range: 3-6), whereas land-based maricultured fish were not infected. Hatching success and time to first and last hatch was determined for a range of water temperature (22, 30, 32 and 34°C) and salinity (0, 11, 22, 35 and 40‰) combinations representing current and predicted climate conditions. There was a significant interaction between water temperature and salinity on the hatching success of L. latis nauplii. Eggs hatched in all temperature treatments, with the greatest hatching success at 30°C and 32°C (98 and 92% success, respectively) in 35‰. Hatching did not occur at 0‰ and was severely reduced at 11‰ (1.6% success). Hatching began within 6h at all water temperatures with >95% of eggs hatched within 30h at 30, 32 and 34°C and within 60h at 22°C. Adult parasites differed from the original description by the presence of the parabasal flagellum, small setae on the legs and caudal rami and minor incongruences regarding morphological measurements. The life cycle of L. latis includes three free living stages and five parasitic stages. Although L. latis exhibits broad environmental tolerance, freshwater can be used as an effective management strategy to break the life cycle in aquaculture. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Effect of electron irradiation in hatching eggs experimentally inoculated with salmonella enteriditis, on hatch ability and broiler performance; Efecto de la irradiacion con electrones en huevos fertiles inoculados experimentalmente con salmonella enteriditis sobre la incubabilidad y desarrollo productivo

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda S, M P

    1996-12-31

    The effect of four doses of electrons irradaition on bacteriologic population in hatching egg following experimental shell contamination with Salmonella enteriditis phage type 13 was investigated. Fresh, whole, intact raw eggs were inoculated with 10{sup 9} Colony-Forming Units of Salmonella enteriditis, eggs were irradiated with a beam electron source at either: 0.5, 1, 2 and 3 KGy. The bacteriologic evaluation was made with Gentry`s and Williams` technic. After the irradiation the groups were taken to commercial hatchery and were incubated in satndards conditions. The bacteriologic evaluation of the shell showed a significant 2.8 log reduction on the group of eggs that were irradiated with 1 KGy as compared with 0.5 KGy doses group and control group (P<0.05). A negative correlation (r=-0.93) between irradiation doses and CFU (P<0.05) was also observed. Bacteriologic evaluation of the internal shell membrane exhibited a highly significant inactivation (P<0.01) of S. enteriditis of 100% in the group of eggs irradiated at 2 and 3 kGy. A high negative correlation (r=-0.90) between irradiation doses and samples of internal structures (P<0.05) was observed. The results obtained suggested that the electrons irradiation may be use like a control system of salmonelosis on egg and like desinfection system on hatching eggs because it did not cause any effect on hatchability and broiler performance. (Author).

  10. No maternal or direct effects of ocean acidification on egg hatching in the Arctic copepod Calanus glacialis.

    Science.gov (United States)

    Thor, Peter; Vermandele, Fanny; Carignan, Marie-Helene; Jacque, Sarah; Calosi, Piero

    2018-01-01

    Widespread ocean acidification (OA) is transforming the chemistry of the global ocean and the Arctic is recognised as the region where this transformation will occur at the fastest rate. Moreover, many Arctic species are considered less capable of tolerating OA due to their lower capacity for acid-base regulation. This inability may put severe restraints on many fundamental functions, such as growth and reproductive investments, which ultimately may result in reduced fitness. However, maternal effects may alleviate severe effects on the offspring rendering them more tolerant to OA. In a highly replicated experiment we studied maternal and direct effects of OA predicted for the Arctic shelf seas on egg hatching time and success in the keystone copepod species Calanus glacialis. We incubated females at present day conditions (pHT 8.0) and year 2100 extreme conditions (pHT 7.5) during oogenesis and subsequently reciprocally transplanted laid eggs between these two conditions. Statistical tests showed no effects of maternal or direct exposure to OA at this level. We hypothesise that C. glacialis may be physiologically adapted to egg production at low pH since oogenesis can also take place at conditions of potentially low haemolymph pH of the mother during hibernation in the deep.

  11. AFSC/RACE/SAP/Swiney: Primiparous and multiparous Tanner crab egg extrusion, embryo development and hatching

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study compares timing of egg extrusion, embryo development, timing and duration of eclosion, and incubation periods of Kodiak, Alaska primiparous and...

  12. A method to evaluate relative ovicidal effects of soil microfungi on thick-shelled eggs of animal-parasitic nematodes

    DEFF Research Database (Denmark)

    Thapa, Sundar; Meyling, Nicolai Vitt; Katakam, Kiran Kumar

    2015-01-01

    Thick-shelled eggs of animal-parasitic ascarid nematodes can survive and remain infective in the environment for years. The present study evaluated a simple in vitro method and evaluation scheme to assess the relative effect of two species of soil microfungi, Pochonia chlamydosporia Biotype 10...

  13. Anthelmintic activity of acetone extracts from South African plants used on egg hatching of Haemonchus contortus

    CSIR Research Space (South Africa)

    Sakong, BM

    2016-01-01

    Full Text Available , C.M.L., Moraes, S.M. & Vieira, L.S., 1999, ‘In vitro ovicidal and larvicidal effect of the plants Spigelia anthelmia and Momordica charantia against the nematode Haemonchus contortus’, Ciência Animal 9, 67–73. Bizimenyera, E.S., Githiori, J... ruminants of semi-arid Brazilian northeast’, Ciência Animal 10, 294–300. Mendoza de Gives, P., Crespo, J.F., Rodriguez, D.H., Prats, V.V., Hernandez, E.L. & Fernandez, G.E.O., 1998, ‘Biological control of Haemonchus contortus infective larvae in ovine...

  14. Shell Properties, Water Vapor Loss, and Hatching Success of Eggs from a Rain Forest Population of the Pearly-eyed Thrasher (Margarops fuscatus)

    Science.gov (United States)

    WAYNE J. ARENDT

    2005-01-01

    I calculated various shell properties, water vapor loss, and hatching success of eggs of the Pearly-eyed Thrasher (Margarops fuscatus) using measurements obtained during a long-term study in the Luquillo Mountains, Puerto Rico. Empirical results were comparable to standard reference formulae, demonstrating that published formulae can be used with confidence by field...

  15. EFFECT OF STORAGE TEMPERATURE PERCENTAGE OF EGG HATCHING OF AEDES AEGYPTI IN LABORATORY=PENGARUH SUHU PENYIMPANAN TERHADAP PRESENTASE TETAS TELUR Aedes aegypti DI LABORATORIUM

    Directory of Open Access Journals (Sweden)

    Riyani Setiyaningsih

    2015-03-01

    Full Text Available EnglishABSTRACTAedes aegypti is the vector of Dengue Hemorrhagic Fever (DHF in Indonesia. Ae. aegypti has a high reproductive capacity, one female mosquitoes can lay 100-150 eggs. Eggs of Ae. aegypti can survive on dry temperatures within a few months, thus increasing the chances of transmission of dengue virus The aim of the study was to determine the effect of temperature on egg hatching percentage of Ae. aegypti. Eggs Ae. aegypti colonization in laboratory results are stored at room temperature and refrigerator temperature. Observations percentage of eggs hatching was observed at month zero, one, two, third, fourth, fifth, and sixth. The results of the study until the sixth month percentage of hatching eggs at room temperature was 63,17, 59,26, 24,33, 13,62, 10, and 0%. While storage on egg hatching refrigerator not occur in the first to sixth.INDONESIANAedes aegypti merupakan vektor Demam Berdarah Dengue (DBD di Indonesia. Ae. aegypti memiliki kemampuan reproduksi yang tinggi, satu ekor nyamuk betina dapat bertelur 100-150 butir telur. Telur Ae. aegypti mampu bertahan hidup pada suhu kering dalam beberapa bulan sehingga memperbesar peluang terjadinnya proses penularan virus DBD. Tujuan penelitian adalah mengetahui pengaruh suhu dan lama penyimpanan terhadap presentase penetasan telur Ae. aegypti. Telur Ae. aegypti hasil kolonisasi di laboratorium disimpan pada suhu ruang dan suhu refrigerator. Pengamatan presentase penetasan telur diamati pada bulan ke nol, kesatu, kedua, ketiga, keempat, kelima, dan keenam. Hasil penelitian pada bulan bertama sampai keenam presentase penetasan telur pada suhu ruang adalah 63,17, 59,26, 24,33, 13,62, 10, dan 0%. Sedangkan penyimpanan pada suhu kukas tidak terjadi penetasan telur pada bulan pertama sampai keenam.

  16. How to hatch from an egg of great structural strength. A study of the common cuckoo

    Czech Academy of Sciences Publication Activity Database

    Honza, Marcel; Picman, J.; Grim, T.; Novák, V.; Čapek Jr., Miroslav; Mrlík, Vojtěch

    2001-01-01

    Roč. 32, č. 3 (2001), s. 249-255 ISSN 0908-8857 R&D Projects: GA AV ČR IAA6087801 Institutional research plan: CEZ:AV0Z6093917 Keywords : Cuculus canorus * eggs Subject RIV: EG - Zoology Impact factor: 1.353, year: 2001

  17. An egg injection technique to evaluate the effect of polychlorinated biphenyls on the hatching success of the snapping turtle (Chelydra serpentina serpentina).

    Science.gov (United States)

    Schnars, Jeanette L; Voss, Margaret A; Stauffer, Jay R

    2011-04-01

    Embryos of oviparous organisms are exposed to contaminants by two pathways: contaminant uptake from the surrounding environment, and the transfer from female to offspring (maternal transfer). The initial source of contaminant exposure for most embryos is likely to be maternal transfer; therefore, maternal transfer studies are critical in determining the effects of contaminants on future populations. Injection of contaminants directly into eggs is one route of experimental contaminant exposure that permits controlled doses and potential reliable replication. This technique, however, has been used in the past with little success in reptiles. The objective of the present study was to evaluate egg injection as a means of mimicking maternal transfer of polychlorinated biphenyls (PCBs) to snapping turtle eggs. Eggs from several clutches were injected with a PCB solution and incubated at several temperatures and moisture levels to measure interactive effects of injection, environmental condition, and contaminant load on hatching success. The injection technique allowed for application of consistent and specific doses among replicates. Overall hatching success in this study was 61% and was as high as 71% within specific treatments. Hatching success was much higher in this study than in other studies using egg injections to mimic maternal transfer in chelonians and crocodilians. Copyright © 2010 SETAC.

  18. Effect of cobalt 60 gamma-ray irradiation on the hatching process of chicken eggs

    International Nuclear Information System (INIS)

    Ohkuma, Yoshikazu

    1981-01-01

    An experiment on fertilized chicken eggs was carried out to determine the effects of 60 Co irradiation on the embryos, their fatality, and growth impairment or deformity, in particular. The experimental groups, consisting of 10 eggs each, recieved a 60 Co irradiation of 50 to 2,000 rads on any one day between day 0 and day 20 of incubation. The larger the irradiation dose, the greater was the number of dead embryos. The fatality was higher in the groups receiving irradiation in the earlier stage (1st week). The resultant death was a chronic one. The irradiation also caused body weight decrease and growth impairment. A decrease in the brain and liver weights was noted, suggesting insufficiency in these organs. Deformity occurred in 4%, most of which involved impairments of skeletal growth, of the bones of the extremities and the bill, in particular. Administration of the SH amino acid, cysteine tended to alleviate the adverse effects of the 60 Co irradiation. These results for fertilized chicken eggs suggest the possibility of abortion and the occurrence of deformities in human fetuses if they should be subjected to 60 Co irradiation. (author)

  19. Arrested embryonic development: a review of strategies to delay hatching in egg-laying reptiles

    Science.gov (United States)

    Rafferty, Anthony R.; Reina, Richard D.

    2012-01-01

    Arrested embryonic development involves the downregulation or cessation of active cell division and metabolic activity, and the capability of an animal to arrest embryonic development results in temporal plasticity of the duration of embryonic period. Arrested embryonic development is an important reproductive strategy for egg-laying animals that provide no parental care after oviposition. In this review, we discuss each type of embryonic developmental arrest used by oviparous reptiles. Environmental pressures that might have directed the evolution of arrest are addressed and we present previously undiscussed environmentally dependent physiological processes that may occur in the egg to bring about arrest. Areas for future research are proposed to clarify how ecology affects the phenotype of developing embryos. We hypothesize that oviparous reptilian mothers are capable of providing their embryos with a level of phenotypic adaptation to local environmental conditions by incorporating maternal factors into the internal environment of the egg that result in different levels of developmental sensitivity to environmental conditions after they are laid. PMID:22438503

  20. Hatching synchrony in birds

    OpenAIRE

    Tippeltová, Zuzana

    2011-01-01

    This bachelor thesis is about hatching synchrony in birds. Generally, among birds there are two types of hatching - asynchronous and synchronous- and the type of hatching is primarily determined by the time of the onset of incubation. In many bird species, including most precocial ones, incubation does not begin until the last egg has been laid, which results in hatching of all the eggs within a few hours. In synchronously-hatched broods, all the chicks are about the same age. Thus no single ...

  1. Comparison of McMaster and FECPAKG2 methods for counting nematode eggs in the faeces of alpacas.

    Science.gov (United States)

    Rashid, Mohammed H; Stevenson, Mark A; Waenga, Shea; Mirams, Greg; Campbell, Angus J D; Vaughan, Jane L; Jabbar, Abdul

    2018-05-02

    This study aimed to compare the FECPAK G2 and the McMaster techniques for counting of gastrointestinal nematode eggs in the faeces of alpacas using two floatation solutions (saturated sodium chloride and sucrose solutions). Faecal eggs counts from both techniques were compared using the Lin's concordance correlation coefficient and Bland and Altman statistics. Results showed moderate to good agreement between the two methods, with better agreement achieved when saturated sugar is used as a floatation fluid, particularly when faecal egg counts are less than 1000 eggs per gram of faeces. To the best of our knowledge this is the first study to assess agreement of measurements between McMaster and FECPAK G2 methods for estimating faecal eggs in South American camelids.

  2. Effects of age, sex, lactation and social dominance on faecal egg count patterns of gastrointestinal nematodes in farmed eland (Taurotragus oryx).

    Science.gov (United States)

    Vadlejch, J; Kotrba, R; Čadková, Z; Růžičková, A; Langrová, I

    2015-10-01

    The eland is a large African antelope that can be bred in a temperate climate, under similar conditions and production systems as cattle. However, knowledge of parasites in farmed elands outside the area of their native habitat is still limited, and information concerning factors that influence these parasites is lacking. Therefore, faecal samples from an entire herd of elands, including calves and adult females and males, were examined monthly over a one year period. Almost 84% of the animals were found to be positive for gastrointestinal nematodes. Strongyle-type eggs were most frequently detected (prevalence 75%), followed by Capillaria sp., Nematodirus sp. and Trichuris sp. eggs. Following culturing eggs to infective larvae, Teladorsagia sp., Trichostrongylus sp., Nematodirus sp., Cooperia sp. and Oesophagostomum sp. were identified. Following necropsy of two calves that died during the study one abomasal nematode (Teladorsagia circumcincta), five small intestinal nematode species (Nematodirus helvetianus, N. spathiger, Cooperia oncophora, C. curticei and Capillaria bovis) and two large intestinal nematodes (Oesophagostomum venulosum and Trichuris ovis) were recovered. From these findings, it is evident that the eland harbours nematodes that are typical for domestic cattle and small ruminants. Morphological and morphometric analyses of recovered nematodes revealed that these parasites do not require any special morphological adaptation to establish infection in elands. The faecal output of strongyle-type and Nematodirus sp. eggs was seasonal, with the highest egg production taking place during spring and summer. Calves had higher faecal egg counts (for all the monitored nematode species) than adults did. Lactation in females was significantly (Pnematode egg shedding. Social dominance also affected faecal egg count patterns. The lower the hierarchical position among adults (regardless of sex), the higher the risk of nematode infection. This effect was evident

  3. Patterns of faecal nematode egg shedding after treatment of sheep with a long-acting formulation of moxidectin.

    Science.gov (United States)

    Crilly, James Patrick; Jennings, Amy; Sargison, Neil

    2015-09-15

    Much of the current information on the effects of long-acting anthelmintics on nematode populations derives either from research farms or mathematical models. A survey was performed with the aim of establishing how moxidectin is currently being used on sheep farms in the south-east of Scotland. A study was undertaken on a subsection of the surveyed farms to examine the effects of long-acting moxidectin treatments in both spring and autumn on faecal nematode egg output. The survey showed that whole flock treatments of injectable 2% moxidectin were used to control sheep scab on 21% of farms. Injectable 2% moxidectin and oral moxidectin were used to control the periparturient rise in faecal nematode egg shedding by ewes on 13% and 55% of farms respectively. The effects of injectable 2% moxidectin treatment on faecal nematode egg shedding post-treatment in both the autumn and spring were investigated by faecal nematode egg counts at the time of treatment and at 2-weekly interval thereafter on eight and six farms in the autumn and spring, respectively. Faecal egg shedding recommenced at 8 weeks (autumn) and 4 weeks (spring) post-treatment. Counts increased to a peak and then declined. The mean (95% confidence interval) peak counts post-treatment were 2.8 (0.6, 5.1), 3.6 (1.7, 5.5) and 53.5 (25.1, 82.0) eggs per gram (EPG) for autumn-treated ewes, autumn-treated lambs and spring-treated ewes respectively. The spring treated sheep showed a statistically significantly earlier return to faecal egg shedding (p=0.0125, p=0.0342) compared to both other groups, statistically significantly higher peak in egg counts than the autumn treated sheep (pegg counts (p=0.0148). There was no statistically significant difference in the timing of the peak FECs between autumn and spring (p=0.211). The FECs of all groups of sheep treated with an injectable long-acting formulation of moxidectin became positive earlier than would be expected from the period of persistence given on the datasheet

  4. Effect of Musa spp. extract on eggs and larvae of gastrointestinal nematodes from infected sheep

    Directory of Open Access Journals (Sweden)

    Natalie Neuwirt

    2015-12-01

    Full Text Available Helminthes are listed as one of the main problems facing the development of goat and sheep production. Haemonchus contortus is the specie that causes greatest negative impact in ranching. Resistance to anti-parasitic drugs and demand for residue-free animal-derived food products has elevated the importance of herbal treatments. The aim of this study was to develop an extract of Musa spp. and assess by in vitro testing, the anthelmintic effect on eggs and larvae in the gastrointestinal nematodes in sheep. Stool samples from sheep naturally infected were used to obtain eggs and larvae and was then followed by a test of hatchability and a larval migration inhibition test. In vitro tests on the inhibition of larval hatchability at concentrations of 160 and 180 mg mL-1 of larval extracts and inhibition of migration at concentrations of 800 and 1000 mg mL-1 were observed. The results indicate that the use of banana leaf has an anthelmintic effect and that in vivo studies on the applicability of this technology to the field should be made to further understanding and bring more information to what has already been revealed in this study.

  5. Egg hatching response to a range of ultraviolet-B (UV-B) radiation doses for four predatory mites and the herbivorous spider mite Tetranychus urticae.

    Science.gov (United States)

    Koveos, Dimitrios S; Suzuki, Takeshi; Terzidou, Anastasia; Kokkari, Anastasia; Floros, George; Damos, Petros; Kouloussis, Nikos A

    2017-01-01

    Egg hatchability of four predatory mites-Phytoseiulus persimilis Athias-Henriot, Iphiseius [Amblyseius] degenerans Berlese, Amblyseius swirskii Athias-Henriot, and Euseius finlandicus Oudemans (Acari: Phytoseiidae)-and the spider mite Tetranychus urticae Koch (Acari: Tetranychidae) was determined under various UV-B doses either in constant darkness (DD) or with simultaneous irradiation using white light. Under UV-B irradiation and DD or simultaneous irradiation with white light, the predator's eggs hatched in significantly lower percentages than in the control non-exposed eggs, which indicates deleterious effects of UV-B on embryonic development. In addition, higher hatchability percentages were observed under UV-B irradiation and DD in eggs of the predatory mites than in eggs of T. urticae. This might be caused by a higher involvement of an antioxidant system, shield effects by pigments or a mere shorter duration of embryonic development in predatory mites than in T. urticae, thus avoiding accumulative effects of UV-B. Although no eggs of T. urticae hatched under UV-B irradiation and DD, variable hatchability percentages were observed under simultaneous irradiation with white light, which suggests the involvement of a photoreactivation system that reduces UV-B damages. Under the same doses with simultaneous irradiation with white light, eggs of T. urticae displayed higher photoreactivation and were more tolerant to UV-B than eggs of the predatory mites. Among predators variation regarding the tolerance to UV-B effects was observed, with eggs of P. persimilis and I. degenerans being more tolerant to UV-B radiation than eggs of A. swirskii and E. finlandicus.

  6. Host Status of Different Potato (Solanum tuberosum) Varieties and Hatching in Root Diffusates of Globodera ellingtonae.

    Science.gov (United States)

    Zasada, Inga A; Peetz, Amy; Wade, Nadine; Navarre, Roy A; Ingham, Russ E

    2013-09-01

    Globodera ellingtonae was detected in Oregon in 2008. In order to make decisions regarding the regulation of this nematode, knowledge of its biology is required. We determined the host status of a diversity of potato (Solanum tuberosum) varieties in soil-based experiments and identified hatching stimulants in in vitro hatching assays. 'Russet Burbank,' 'Desiree,' 'Modac,' 'Norland,' 'Umatilla,' and 'Yukon Gold' were good hosts (RF > 14) for G. ellingtonae. Potato varieties 'Maris Piper,' 'Atlantic,' and 'Satina,' all which contain the Ro1 gene that confers resistance to G. rostochiensis, were not hosts for G. ellingtonae. In in vitro hatching assays, G. ellingtonae hatched readily in the presence of diffusates from potato (PRD) and tomato (Solanum lycopersicum; TRD). Egg hatch occurred in an average of between 87% and 90% of exposed cysts, with an average of between 144 and 164 juveniles emerging per cyst, from PRD- and TRD-treated cysts, respectively. This nematode hatched rapidly in the presence of PRD and TRD, with at least 66% of total hatch occurring by day 3 of exposure. There was no dose-response of egg hatch to concentrations of PRD or TRD ranging from 1:5 to 1:100 diffusate to water. When G. ellingtonae was exposed to root diffusates from 21 different plants, hatch occurred in 0% to 70% of exposed cysts, with an average of between 0 to 27 juveniles emerging per cyst. When root diffusate-exposed cysts were subsequently transferred to PRD to test viability, root diffusates from arugula (Eruca sativa), sudangrass (Sorghum bicolor subsp. drummondii), and common vetch (Vicia sativa) continued to inhibit egg hatch compared with the other root diffusates or water in which hatch occurred readily (60 to 182 juveniles emerging per cyst). Previously known hatching stimulants of G. rostochiensis and G. pallida, sodium metavanadate, sodium orthovanadate, and sodium thiocyanate, stimulated some egg hatch. Although, Globodera ellingtonae hatched readily in PRD and TRD

  7. Joint Effect of Solar UVB and Heat Stress on the Seasonal Change of Egg Hatching Success in the Herbivorous False Spider Mite (Acari: Tenuipalpidae).

    Science.gov (United States)

    Sudo, M; Osakabe, M

    2015-12-01

    Seasonal population dynamics of an herbivorous mite has been documented in terms of the relationship between thermoresponses and temporal biological factors such as resource availability or predation risk. Although recent studies emphasize the deleterious effects of solar ultraviolet-B (UVB; 280-320 nm wavelengths) radiation on plant-dwelling mites, how UVB affects mite population remains largely unknown. On a wild shrub Viburnum erosum var. punctatum in Kyoto, an herbivorous false spider mite, Brevipalpus obovatus Donnadieu, occurs only in autumn. Females of this species lay one-third of their eggs on upper leaf surfaces. Oviposition on upper surfaces is beneficial for avoiding predation by phytoseiids, but exposes eggs to solar UVB and heat stress. To test the hypothesis that the seasonal occurrence of this mite is determined by interactions between solar UVB radiation and temperature, we examined variation in egg hatching success under near-ambient and UV-attenuated sunlight conditions from spring to autumn. The UV-attenuation significantly improved hatching success. However, most eggs died under heat stress regardless of UV treatments in July and August. We established a deterministic heat stress-cumulative UVB dose-egg hatching success response model, which we applied to meteorological data. The model analyses illustrated lower and higher survivability peaks in late May and October, respectively, which partly corresponded to data for annual field occurrence, indicating the importance of solar UVB radiation and heat stress as determinants of the seasonal occurrence of this mite. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Egg production and hatching success of Calanus chilensis and Acartia tonsa in the northern Chile upwelling zone (23°S), Humboldt Current System

    Science.gov (United States)

    Ruz, Paula M.; Hidalgo, Pamela; Yáñez, Sonia; Escribano, Rubén; Keister, Julie E.

    2015-08-01

    Oxygen Minimum Zones (OMZ's) are expanding and intensifying as result of climate change, affecting Eastern Boundary Upwelling Systems. Local effects of vertical movements of OMZ's that result from changes in upwelling intensity could reduce or expand the oxygenated surface layer that most zooplanktonic species inhabit in coastal areas. Using the copepods Calanus chilensis and Acartia tonsa as model organisms, an experimental test of the impact of different dissolved oxygen (DO) concentrations (between 0.5 and 5 ml L- 1) on egg production and hatching success was carried out and compared with field estimations of egg production, female and egg abundance in Mejillones Bay (23°S). Abundance of C. chilensis was highly variability and no consistent pattern in egg production and hatching success was found across DO levels, whereas A. tonsa egg production had maximum values between 2.6 and 4.7 ml O2 L- 1 and hatching success was positively correlated with DO (r = 0.75). In the field, temperature was the main factor controlling the dynamics of both species, while Chl-a and DO were also correlated with C. chilensis and A. tonsa, respectively. Principal Component Analysis showed that abundances of both copepods were controlled by temperature, stratification, OMZ depth, and Ekman transport, which together explained more than 70% of the total variance and were the main factors that modulated the populations of C. chilensis and A. tonsa in the upwelling zone of northern Chile (23°S). The differential responses of C. chilensis and A. tonsa to changes in DO concentrations associated with vertical movements of the OMZ suggest that C. chilensis may be better adapted to hypoxic conditions than A. tonsa, however both species are successful and persistent all year-round. We suggest that physiological responses of copepods could be used to evaluate population dynamics affected by the shoaling of OMZ's and the repercussions to trophic food webs of eastern boundary current systems.

  9. Effect of pre and or post-hatching treatment of broiler eggs with thyroxin and growth hormones on thyroid histology and function of growing chicks

    International Nuclear Information System (INIS)

    Gamal, M.H.; El-Gendi, G.M.

    2003-01-01

    A total number of 1340 eggs from arbor acres parent breed were used in this study. Eggs were divided into two divisions were then sub divided according to the incubation relative humidity (48% and 52%). Eggs of each division were then subdivided into ten groups, eggs of 1 s t, 2 n d groups were injected with 0.05, 0.10 and 0.15 MU elroxin, respectively, those of the 4 t h, 5 t h, and 6 t h groups wereinjectived with 0.05, 0.10 and 0.15 mg carbimazole, respectively, while eggs of the 7 t h, 8 t h and 9 t h groups were injected with 0.005, 0.02 and 0.04 I.U. growth hormone respectively. Eggs of the 10 t h group was injected with distilled water and used as control group. Each group was divided into two divisions, eggs of the first division were injected just before incubation (into the air cell) and those of the second division were injected at the 9 t h day of incubation period (into the embryonic allantoic cavity). A total number of 960 hatched chicks were randomly selected (24chicks of each group)

  10. Protein turnover in the breast muscle of broiler chicks and studies addressing chlorine dioxide sanitation of hatching eggs, poultry leg problems and wheat middling diets for laying hens

    International Nuclear Information System (INIS)

    Patterson, P.H.

    1988-01-01

    Developmental changes occurred in breast muscle Ks measured by 14 C-tyrosine incorporation at 10, 16, 22 and 34 days of age. Protein synthesis rates decreased as the birds matures: 30 to 11.2%/d between 10 and 34 days of age. In a second study birds fed diets low in lysine or protein-energy had reduced fractional rates of protein synthesis and free tyrosine, branched chain and large neutral amino acid concentrations as compared to control birds the same body weight. Artificial weight loading and reduced dietary protein levels were used to study the effects of body weight on the severity of leg deformities in chicks and poults. Experiments investigating the practicality of wheat middlings as an alternate feedstuff for laying hens suggested that high levels in the diet will reduce egg production, feed conversion, hen livability and egg yolk color. Lastly, chlorine dioxide foam and dipping solutions were compared with formaldehyde fumigation for sanitizing hatching eggs

  11. Pengaruh Selang Waktu Peletakkan Terhadap Keberhasilan Penetasan Telur Penyu Hijau (Chelonia mydas L. (Effect of Planting Time on Egg Hatching Success of Green Turtle (Chelonia mydas L.

    Directory of Open Access Journals (Sweden)

    Edi Wibowo Kushartono

    2014-09-01

    Full Text Available Salah satu usaha konservasi melindungi Penyu hijau (Chelonia mydas L. yaitu dengan tindakan relokasi dengan memindahkan telur dari sarang alami ke tempat penetasan semi alami. Waktu pemindahan dan peletakan telur yang tepat sangat diperlukan untuk memperoleh daya tetas maksimal. Tujuan penelitian ini untuk mengetahui pengaruh selang waktu peletakan telur Penyu Hijau terhadap keberhasilan penetasannya. Rancangan penelitian adalah Rancangan Acak Kelompok berdasarkan 3 induk yang berbeda dengan perlakuan selang waktu peletakan yaitu 2, 7 dan 12 jam. Pengukuran dan pengamatan kondisi lingkungan dilakukan selama inkubasi. Pengamatan munculnya tukik mulai dilakukan pada hari ke 50 masa inkubasi.  Pembongkaran sarang dilakukan pada hari ke 60 masa inkubasi kemudian dilakukan pembedahan secara manual untuk mengamati telur yang gagal menetas. Hasil menunjukkan bahwa tidak ada pengaruh nyata secara signifikan adanya perbedaan selang waktu peletakan terhadap keberhasilan penetasan dan keberhasilan kemunculan. Namun selang waktu peletakan dengan nilai yang baik ditunjukkan pada 2 jam, dilanjutkan dengan 12 jam dan 7 jam. Kata kunci: penetasan, penyu hijau (Chelonia mydas L., semi alami One of the conservation efforts undertaken to protect the green turtle (C. mydas L. is by relocation of the nest where the eggs are removed from natural to semi-natural hatchery. A right time for the removal and burial of eggs are needed to obtain maximum hatching rate. The purpose of this study is to determine the impact of interval laying period on the hatching success of the green turtle eggs. Randomized block design is used which is based on three different turtles with treatment interval of burying, which is 2, 7, and 12 h. Measurements and observations were made during the environmental conditions of the incubation period. Observations hatchling emergence started on day 50 of incubation. Nest destruction was conducted on the 60th day incubation then eggs that failed to

  12. Toxicity of 2,4-diacetylphloroglucinol (DAPG) to plant-parasitic and bacterial-feeding nematodes.

    Science.gov (United States)

    Meyer, Susan L F; Halbrendt, John M; Carta, Lynn K; Skantar, Andrea M; Liu, Ting; Abdelnabby, Hazem M E; Vinyard, Bryan T

    2009-12-01

    The antibiotic 2,4-diacetylphloroglucinol (DAPG) is produced by some isolates of the beneficial bacterium Pseudomonas fluorescens. DAPG is toxic to many organisms, and crop yield increases have been reported after application of DAPG-producing P. fluorescens. This study was conducted to determine whether DAPG is toxic to selected nematodes. The plant-parasitic nematodes Heterodera glycines, Meloidogyne incognita, Pratylenchus scribneri and Xiphinema americanum, and the bacterial-feeding nematodes Caenorhabditis elegans, Pristionchus pacificus, and Rhabditis rainai, were immersed in concentrations ranging from 0 to 100 μg/ml DAPG. Egg hatch and viability of juveniles and adults were determined. DAPG was toxic to X. americanum adults, with an LD₅₀ of 8.3 μg/ml DAPG. DAPG decreased M. incognita egg hatch, but stimulated C. elegans hatch during the first hours of incubation. Viability of M. incognita J2 and of C. elegans J1 and adults was not affected. There were no observed effects on the other nematodes. The study indicated that DAPG is not toxic to all nematodes, and did not affect the tested species of beneficial bacterial-feeding nematodes. Augmentation of DAPG-producing P. fluorescens populations for nematode biocontrol could be targeted to specific nematode species known to be affected by this compound and by other antibiotics produced by the bacteria, or these bacteria could be used for other possible effects, such as induced plant resistance.

  13. Effects of water salinity on hatching of egg, growth and survival of larvae and fingerlings of snake head fish, Channa striatus

    Directory of Open Access Journals (Sweden)

    Thumronk Amornsakun

    2017-04-01

    Full Text Available A study on the effect of water salinity ranging from 0-30 ppt on hatching success of snake head fish, Channa striatus was conducted in a 15-liter glass aquarium (water volume 10 liters containing 500 eggs for various levels of water salinity. Fertilization rates at 0, 5, 10, 11, 12, 13 and 14 ppt were 69.33, 72.67, 71.33, 72.67, 82.00, 73.33 and 10.67%, respectively. The fertilization rate at 12-13 ppt salinity was significantly (P0.05 among 0, 5 and 10 ppt.

  14. Infection Assay of Cyst Nematodes on Arabidopsis Roots.

    Science.gov (United States)

    Bohlmann, Holger; Wieczorek, Krzysztof

    2015-09-20

    Plant parasitic nematodes are devastating pests on many crops. Juveniles (J2) of cyst nematodes invade the roots to induce a syncytium. This feeding site is their only source of nutrients. Male nematodes leave the roots after the fourth molt to mate with females. The females stay attached to their syncytia throughout their life and produce hundreds of eggs, which are contained in their bodies. When the females die their bodies form the cysts, which protect the eggs. Cysts can survive for many years in the soil until favorable conditions induce hatching of the juveniles. The beet cyst nematode Heterodera schachtii ( H. schachtii )is a pathogen of sugar beet ( Beta vulgaris ) but can also complete its life cycle on Arabidopsis roots growing on agar plates under sterile conditions. We present here protocols for a stock culture of H. schachtii and an infection assay on agar plates.

  15. Effects of preincubation heating of broiler hatching eggs during storage, flock age, and length of storage period on hatchability.

    Science.gov (United States)

    Gucbilmez, M; Ozlü, S; Shiranjang, R; Elibol, O; Brake, J

    2013-12-01

    The effects of heating of eggs during storage, broiler breeder age, and length of egg storage on hatchability of fertile eggs were examined in this study. Eggs were collected from Ross 344 male × Ross 308 broiler breeders on paper flats, held overnight (1 d) at 18°C and 75% RH, and then transferred to plastic trays. In experiment 1, eggs were obtained at 28, 38, and 53 wk of flock age. During a further 10 d of storage, eggs either remained in the storage room (control) or were subjected to a heat treatment regimen of 26°C for 2 h, 37.8°C for 3 h, and 26°C for 2 h in a setter at d 5 of storage. In experiment 2, eggs from a flock at 28 wk of age were heated for 1 d of a 6-d storage period. Eggs from a 29-wk-old flock were either heated at d 1 or 5 of an 11-d storage period in experiment 3. In experiment 4, 27-wk-old flock eggs were heated twice at d 1 and 5 of an 11-d storage period. Control eggs stored for 6 or 11 d were coincubated as appropriate in each experiment. Heating eggs at d 5 of an 11-d storage period increased hatchability in experiment 1. Although no benefit of heating 28-wk-old flock eggs during 6 d of storage in experiment 2 was observed, heating eggs from a 29-wk-old flock at d 1 or 5 of an 11-d storage period increased hatchability in experiment 3. Further, heating eggs from a 27-wk-old flock twice during 11 d of storage increased hatchability in experiment 4. These effects were probably due to the fact that eggs from younger flocks had been reported to have many embryos at a stage of development where the hypoblast had not yet fully developed (less than EG-K12 to EG-K13), such that heating during extended storage advanced these embryos to a more resistant stage.

  16. In vitro effects of aqueous extract from Maytenus senegalensis (Lam.) Exell stem bark on egg hatching, larval migration and adult worms of Haemonchus contortus.

    Science.gov (United States)

    Zangueu, Calvin Bogning; Olounlade, Abiodoun Pascal; Ossokomack, Marlyse; Djouatsa, Yolande Noelle Nangue; Alowanou, Goue Géorcelin; Azebaze, Anatole Guy Blaise; Llorent-Martínez, Eulogio José; de Córdova, Maria Luisa Fernández; Dongmo, Alain Bertrand; Hounzangbe-Adote, Mawulé Sylvie

    2018-05-02

    Maytenus senegalensis is a common shrub which is scattered in tropical Africa. Different parts of this plant have been reported to be useful in traditional medicine against gastrointestinal disorders and intestinal worms. This study evaluated the anthelmintic activity of the aqueous stem bark extract of M. senegalensis using egg hatch assay (EHA), larval migration inhibition assay (LMIA) and adult worms' motility inhibition assay (AMIA). On EHA, the extract concentrations tested resulted in a significant (p  50%). These in vitro results suggest the presence of some anthelmintic properties in M. senegalensis extract, which is traditionally used by small farmers in west and central Africa. These effects may be due to the flavonoids and proanthocyanidins present in the extract and need to be studied under in vivo conditions.

  17. In vitro anti-parasitic effects of sesquiterpene lactones from chicory against cattle nematodes

    DEFF Research Database (Denmark)

    Pena-Espinoza, Miguel Angel; Williams, A.; Boas, Ulrik

    of SL-rich extracts from 2 chicory cultivars on the viability of first-stage larvae (L1) of Ostertagia ostertagi, a pathogenic cattle nematode. Chicory Spadona and Puna II were grown at the same farm and leaves were sampled the same day. 1 g of freeze-dried leaves was extracted in methanol....../water. Resulting extracts were incubated with cellulase enzymes, recovered in ethyl acetate and purified by normal solid-phase extraction. Obtained extracts were dissolved in 100% dimethyl sulfoxide (DMSO). A calf infected with O. ostertagi served as donor of nematode eggs. Eggs were hatched and L1 obtained were...

  18. In vitro anti-parasitic effects of sesquiterpene lactones from chicory against cattle nematodes

    DEFF Research Database (Denmark)

    Pena-Espinoza, Miguel Angel; Williams, A.; Boas, Ulrik

    . In this study we tested the effect of SL-rich extracts from 2 chicory cultivars on the viability of first-stage larvae (L1) of Ostertagia ostertagi, a pathogenic cattle nematode. Chicory Spadona and Puna II were grown at the same farm and leaves were sampled the same day. 1 g of freeze-dried leaves...... was extracted in methanol/water. Resulting extracts were incubated with cellulase enzymes, recovered in ethyl acetate and purified by normal solid-phase extraction. Obtained extracts were dissolved in 100% DMSO. A calf infected with O. ostertagi served as donor of nematode eggs. Eggs were hatched and L1...

  19. Digital image analysis and identification of eggs from bovine parasitic nematodes

    DEFF Research Database (Denmark)

    Sommer, C.

    1996-01-01

    to describe size and shape. A stepwise discriminant analysis was subsequently used to select and rank descriptive features of 4207 eggs according to discriminatory power. Classification criteria were developed by linear discrimination analysis on the basis of selected features, and the criteria evaluated.......1%, and T. axei 83.8%. Classification based on the five most important features gave an overall correct classification of 81.5%. Images of 'unknown' eggs could be identified automatically by the classification criteria after procedural steps performed by PC were linked in a batch program....

  20. Anticipating the free amino acid concentrations in newly hatched pelagic fish larvae based on recently fertilized eggs and temperature

    DEFF Research Database (Denmark)

    Rayner, Thomas Allan; Hwang, Jiang-Shiou; Hansen, Benni Winding

    2017-01-01

    between the species for different FAAs was low, and the most outstanding essential FAAs were leucine, lysine, valine and isoleucine while alanine and serine dominated non-essential FAAs. Overall, leucine could be regarded as the most important among all species due to its common occurrence in newly...... spawned eggs and fast rate of decay. Based on the functions considered in the present study, it is possible to anticipate the availability of FAA diet needed in the form of live feed for pelagic first feeding marine fish larvae in aquaculture at different temperatures....

  1. Trichuris trichiura egg (image)

    Science.gov (United States)

    ... is the classical appearance of the Trichuria (whipworm) egg. The eggs are highly infectious. After a person eats contaminated food, the worms hatch from the eggs and live in the intestine, causing vomiting and ...

  2. The influence of encapsulated embryos on the timing of hatching in the brooding gastropod Crepipatella dilatata

    Science.gov (United States)

    Andrade-Villagrán, P. V.; Baria, K. S.; Montory, J. A.; Pechenik, J. A.; Chaparro, O. R.

    2018-01-01

    Encapsulated embryos are generally thought to play an active role in escaping from egg capsules or egg masses. However, for species that brood their egg capsules, the factors controlling the timing of hatching are largely unclear, particularly the degree to which hatching is controlled by the embryos rather than by the mother, and the degree to which the hatching of one egg capsule influences the hatching of sister egg capsules within the same egg mass. We studied aspects of hatching using the direct-developing gastropod Crepipatella dilatata, which includes nurse eggs in its egg capsules and broods clusters of egg capsules for at least several weeks before metamorphosed juveniles are released. Isolated egg capsules were able to hatch successfully, in the absence of the mother. Moreover, the hatching of one capsule did not cause adjacent sister capsules to hatch. Hatched and un-hatched sister egg capsules from the same egg mass differed significantly in the number of metamorphosed juveniles, average shell size, offspring biomass (juveniles + veliger larvae), and the number of nurse eggs remaining per egg capsule. Differences in when egg capsules hatched within a single egg mass were not explained by differences in egg capsule age. Hatching occurred only after most nurse eggs had been ingested, most offspring had metamorphosed into juveniles, and juveniles had reached a mean shell length > 1.36 mm. Whether the mother has any role to play in coordinating the hatching process or juvenile release remains to be determined.

  3. Association between entomopathogenic nematodes and fungi for control of Rhipicephalus microplus (Acari: Ixodidae).

    Science.gov (United States)

    Monteiro, Caio Márcio Oliveira; Araújo, Laryssa Xavier; Matos, Renata Silva; da Silva Golo, Patrícia; Angelo, Isabele Costa; de Souza Perinotto, Wendell Marcelo; Coelho Rodrigues, Camila Aparecida; Furlong, John; Bittencourt, Vânia Rita Elias Pinheiro; Prata, Márcia Cristina Azevedo

    2013-10-01

    The aim of the study was to assess the effect of the association of entomopathogenic nematodes and fungi on Rhipicephalus microplus. The nematodes used were Heterorhabditis bacteriophora HP88 and Heterorhabditis indica LPP1 and the fungi were Metarhizium anisopliae IBCB 116 and Beauveria bassiana ESALQ 986. In the groups treated with the fungi, the females were immersed for 3 min in a conidial suspension, while in the groups treated with the nematodes, the ticks were exposed to infective juveniles. To evaluate the interaction between entomopathogens, the females were first immersed in a conidial suspension and then exposed to the nematodes. The egg mass weight and hatching percentage values of the groups treated with M. anisopliae IBCB 116 and B. bassiana ESALQ 986 in the two experiments were statistically similar (p > 0.05) to the values of the control group. In the groups treated only with nematodes, there was a significant reduction (p fungus M. anisopliae IBCB 116.

  4. Effect of tanniniferous food from Bauhinia pulchella on pasture contamination with gastrointestinal nematodes from goats.

    Science.gov (United States)

    Lopes, Suzana G; Barros, Lilyan B G; Louvandini, Helder; Abdalla, Adibe L; Costa Junior, Livio M

    2016-02-24

    Tannin-rich plants have been examined as an alternative for controlling the gastrointestinal nematodes in ruminants. In vivo assays typically examine the anthelmintic activity in female fecundity and/or the adult worm burden, without considering other life-cycle stages or the impact on pasture contamination. The aim of the present study was to evaluate the anthelmintic activity of tanniniferous food from Bauhinia pulchella in goats and the potential impact on pasture contamination with the infective larval stage of gastrointestinal nematodes. Sixteen cross breed Boer goats that were naturally infected with gastrointestinal nematodes were fed tanniniferous concentrate from the leaves of B. pulchella and compared to a separate paddock of control animals without condensed tannin supplementation. A range of parasite characteristics were monitored throughout the 63 days of experimentation, including faecal egg count (FEC), egg hatching and relative numbers of hatched helminth larvae on herbage. Worm free tracer animals were used to assess the infective larval stage load of the contaminated pasture. The tanniniferous food did not reduce the combined FEC values, but egg hatching was significantly affected (p food from B. pulchella showed reduced contamination through infective larval stages. Tracer goats maintained in paddocks grazed with animals fed with tanniniferous food had lower numbers of Trichostrongylus colubriformis than did those in the control group (86 % reduction). Condensed tannin from B. pulchella showed anthelmintic activity, affected egg viability and reduced pasture contamination, which led to the reduced infection of the animals by T. colubriformis.

  5. Paleoparasitological finding of eggs of nematodes in rodent coprolites dated at the early Holocene from the archaeological site Cerro Casa de Piedra 7, Santa Cruz, Argentina.

    Science.gov (United States)

    Sardella, N H; Fugassa, M H

    2011-12-01

    The aim of the present study was to examine the parasite remains present in rodent coprolites collected from the archaeological site Cerro Casa de Piedra 7 (CCP7), located in the Perito Moreno National Park (47°57'S, 72°05'W), Santa Cruz Province, Argentina. Eight coprolites obtained from the layer 17, dated at 10,620 ± 40 to 9,390 ± 40 yr B.P., were examined for parasites. Feces were processed whole, rehydrated, homogenized, subjected to spontaneous sedimentation, and examined via light microscopy. Eggs of parasites were measured and photographed. Seven of 8 coprolites possessed 199 eggs of 2, probably new, species of nematodes, including 43 eggs of Heteroxynema sp. Hall, 1916 (Cavioxyura sp. Quentin, 1975) (Oxyurida, Heteroxynematidae), and 156 eggs of Trichuris sp. Roederer, 1761 (Trichinellida, Trichuridae). Heteroxynema sp. is cited for the first time from ancient material worldwide. The finding of Trichuris spp. in both rodents and other host samples from the area under study is indicative of the stability of the biological and environmental conditions for this nematode genus to establish in the Patagonian Early Holocene. The rodent host was assigned to an unknown species of Caviomorpha (Hystricognathi) that lived during the Pleistocenic transition in Patagonia.

  6. Origanum vulgare (Lamiaceae OVICIDAL POTENTIAL ON GASTROINTESTINAL NEMATODES OF CATTLE

    Directory of Open Access Journals (Sweden)

    Luciana Laitano Dias de Castro

    2013-12-01

    Full Text Available Due to anthelmintic resistance in nematodes, several research studies have been developed seeking control alternatives to these parasites. This study evaluated the in vitro action of Origanum vulgare on gastrointestinal nematode eggs of cattle. In order to evaluate the ability to inhibit egg hatch, different dried leaves extracts of this plant were tested, such as dye, hydroalcoholic and aqueous extracts at concentrations varying from 0.62 to 80 mg/mL. Each assay was accompanied by control containing levamisole hydrochloride (0.2 mg/mL, distilled water and 70 ºGL grain alcohol at the same concentration of the extracts. Test results showed that the different O. vulgare extracts inhibited egg hatch of cattle gastrointestinal nematodes at a percentage that varied from 8.8 to 100%; dye and hydroalcoholic extract were the most promising inhibitors. In view of this ovicidal property, O. vulgare may be an important source of viable antiparasitic compounds for nematodiosis control in ruminants.

  7. [Diversity of actinomycetes associated with root-knot nematode and their potential for nematode control].

    Science.gov (United States)

    Luo, Hong-li; Sun, Man-hong; Xie, Jian-ping; Liu, Zhi-heng; Huang, Ying

    2006-08-01

    Twenty actinomycetes were isolated from root-knot nematode eggs and females collected from 11 plant root samples infested by Meloidogyne spp.. The isolates were assigned to the genera Streptomyces, Nocardia and Pseudonocardia respectively, based on analysis of morphological characteristics, cell-wall DAPs and 16S rRNA gene sequences. 80% of them were streptomycetes. Biocontrol potential of the isolates against Meloidogyne hapla was evaluated in liquid culture in vitro. The average percentages of egg parasitism, egg hatching, and juvenile mortality were 54.1, 40.4 and 26.2, respectively. Three Streptomyces strains and one Nocardia strain with high pathogenicity in vitro were selected to determine their ability to reduce tomato root galls in greenhouse. The results demonstrated good biocontrol efficacy (31.4%-56.4%) of the strains.

  8. Efficacy of ivermectin against gastrointestinal nematodes of cattle in Denmark evaluated by different methods for analysis of faecal egg count reduction

    DEFF Research Database (Denmark)

    Pena-Espinoza, Miguel Angel; Thamsborg, Stig M.; Denwood, Matthew J.

    2016-01-01

    The efficacy of ivermectin (IVM) against gastrointestinal nematodes in Danish cattle was assessed by faecal egg count reduction test (FECRT). Six cattle farms with history of clinical parasitism and avermectin use were included. On the day of treatment (Day 0), 20 naturally infected calves per farm...... the performance of the different procedures to correctly identify FEC reduction percentages of simulated bovine FEC data representing the observed real data. In the FECRT, reduced IVM efficacy was detected in three farms by all procedures using data from treated animals only, and in one farm according...

  9. Nematicidal effect of rhizobacteria on plant-parasitic nematodes associated with vineyards.

    Science.gov (United States)

    Aballay, E; Prodan, S; Zamorano, A; Castaneda-Alvarez, C

    2017-07-01

    The action of metabolites and exoenzymes from rhizobacteria on different plant-parasitic nematodes has an influence on the nematicidal efficacy of the microbe. Seven rhizobacteria, divided into two bacterial groups, were evaluated in vitro for nematicidal activity on Meloidogyne ethiopica and Xiphinema index. The direct effect of their filtrates on egg hatching and juveniles of M. ethiopica as well as mobile stages of X. index was evaluated during a 72-h period. The production of four exoenzymes and two metabolites associated with nematode mortality was investigated. Molecular characterization of three isolates was performed, and the physiological profiles and lipase activity of all isolates were obtained using the BIOLOG EcoPlate system. While chitinase and collagenase were measured using the BIOLOG MT2 plate system, protease, hydrogen cyanide and hydrogen sulphide were directly determined in Petri dishes. Nematode mobile stages exposure to the bacterial filtrate revealed a nematicidal effect up to 93.7% on X. Index and up to 83.3% on M. ethiopica. The control of egg hatching varied between 35 and 85%. A positive correlation was found between the mortality of both nematode mobile stages and the concerted activities of the bacterial enzymes as well as the level of the volatile metabolites. The nematicidal effect of rhizobacteria strains varies by nematode genera and among the developmental stages evaluated.

  10. [Controlling effect of antagonist bioorganic fertilizer on tomato root-knot nematode].

    Science.gov (United States)

    Zhu, Zhen; Chen, Fang; Xiao, Tong-jian; Wang, Xiao-hui; Ran, Wei; Yang, Xing-ming; Shen, Qi-rong

    2011-04-01

    Indoor in vitro culture experiment and greenhouse pot experiment were conducted to evaluate the capabilities of three bacterial strains XZ-173 (Bacillus amyloliquefaciens), SL-25 (B. gibsonii), and KS-62 (Paenibacillus polymyxa) that can hydrolyze collagen protein in controlling tomato root-knot nematode. In the in vitro culture experiment, suspensions of XZ-173, SL-25, and KS-62 induced a mortality rate of 75.9%, 66.7%, and 50.0% to the second-stage junior nematode within 24 h, and decreased the egg hatching rate to 17.8%, 28.9% and 37.6% after 7-day incubation, respectively, in contrast to the 17.4% mortality rate and 53.6% egg hatching rate in the control (sterilized water). In the greenhouse pot experiment, the bioorganic fertilizer mixed with equal parts of fermented XZ-173, SL-25, and KS-62 gained the best result, with the root-knot nematode population in rhizosphere soil decreased by 84.0% as compared with the control. The bioorganic fertilizer also decreased the numbers of galls and eggs on tomato roots significantly, and increased the underground and aboveground biomass of tomato. Therefore, antagonist bioorganic fertilizer has promising potential in controlling root-knot nematode.

  11. Impact of direct and indirect application of rising furfural concentrations on viability, infectivity and reproduction of the root-knot nematode, Meloidogyne incognita in Pisum sativum.

    Science.gov (United States)

    Abdelnabby, Hazem; Wang, Yunhe; Xiao, Xueqiong; Wang, Gaofeng; Yang, Fan; Xiao, Yannong

    2016-07-01

    The gradual withdraw of several broadly used nematicides from market has enhanced the need to develop sustainable and eco-friendly alternatives with nematicidal properties. Furfural is one of the promising alternatives to fill this need. Baseline information about the impact of furfural on egg hatch, penetration potential and ultrastructure of nematode is lacking. In this study, the reagent-grade (purity ≥ 99.0%) of furfural was applied against Meloidogyne incognita. In vitro tests showed gradual reduction in either the rate of egg hatch or second stage juvenile (J2) viability of M. incognita when immersed in concentrations ranging from 0 to 10.0 μl/ml furfural. The mean EC50 for J2 and egg hatch was 0.37 and 0.27 μl/ml furfural, respectively. Furfural, even at low concentrations, resulted in a considerable suppression in egg hatch. Hatch was 0.2 ml/kg soil. No adverse effect was detected on plants or free-living nematodes as a result of furfural application. Liquid furfural proved to have superior juvenile-suppressive effect whereas its vapor has such superiority against eggs. Scanning electron microscope (SEM) study showed irregular appearance of the body surface accompanied with some cuticle disfigurement of furfural-treated juveniles. These results indicated that furfural can adversely affect egg hatch, juvenile viability, penetration potential and ultrastructure of M. incognita. Furfural may therefore be of a considerable potential as an appropriate alternative for class I nematicides. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Review on the acute Daphnia magna toxicity test – Evaluation of the sensitivity and the precision of assays performed with organisms from laboratory cultures or hatched from dormant eggs

    Directory of Open Access Journals (Sweden)

    Persoone G.

    2009-08-01

    “Culture/maintenance free” aquatic microbiotests with species of different phylogenetic groups were developed in the early 1990s at the Laboratory for Environmental Toxicology and Aquatic Ecology at the Ghent University in Belgium. These assays which were given the generic name “Toxkits”, are unique in that they employ dormant stages (“cryptobiotic eggs” of the test species, which can be stored for long periods of time and “hatched” at the time of performance of the assays. One of these microbiotests is the Daphtoxkit F magna, which is currently used in many laboratories worldwide for research as well as for toxicity monitoring purposes. The microbiotest technology has several advantages in comparison to the “traditional” tests based on laboratory cultures, especially its independence of the stock culturing burden. However, the acceptance (or possible non-acceptance of performing assays with test organisms obtained from “dormant eggs” should be clearly dictated by the “sensitivity” and “precision” criteria of the former assays in comparison to the latter. The first part of this review therefore thoroughly reviews the scientific literature and of data obtained from various laboratories for assays performed with either D. magna test organisms obtained from lab cultures or hatched from dormant eggs. Attention has focused on data of quality control tests performed on reference chemicals, and in particular on potassium dichromate (K2Cr2O7 for which an acceptability range of 0.6–2.1 mg·L–1 has been set in ISO standard 6341 for the 24 h EC50 of the acute D. magna assay. Mean EC50s, standard deviations and variation coefficients were calculated from the collected data, all of which are presented in tables and figures and discussed in detail. The major conclusions drawn from the analysis of the large number of quality control (QC data on the acute D. magna toxicity test are that : (1 Virtually all results from assays performed with

  13. The killing effects of ultraviolet light and x-rays on free-living nematode, Rhabditidae tokai

    International Nuclear Information System (INIS)

    Ishii, Naoaki; Suzuki, Kenshi

    1980-01-01

    The life-shortening effects of ultraviolet light (UV) and X-rays were investigated with a strain of free-living nematode, Rhabditidae tokai. UV exhibited a significant life-shortening effect on adult worms, and it also inhibited growth of larvae, hatching of eggs and reproduction. Sensitivity to UV was decreased with increasing ages. In contrast, nematodes showed a marked resistance to X-rays. Data were obtained suggesting that X-ray-induced single-strand breaks in DNA can be rapidly and efficiently rejoined by a repair mechanism. Malformations were observed when immature larvae were irradiated with X-rays. (author)

  14. Copepod recruitment and food composition : Do diatoms affect hatching success?

    DEFF Research Database (Denmark)

    Jonasdottir, Sigrun; Kiørboe, Thomas

    1996-01-01

    was fed several different diets while egg production and hatching success were monitored. The diet was analysed for fatty acid content as an indicator of food quality. Both egg production and hatching were found to be affected by the nutritional quality of the food. Hatching was also highly dependent......Laboratory experiments were conducted to differentiate between factors controlling the hatching success of copepod eggs. Factors that could affect viability of eggs; viz food quality, female condition and external factors were investigated. In a series of experiments the copepod Acartia tonsa Dana...

  15. Are all eggs equal?

    NARCIS (Netherlands)

    Nangsuay, A.

    2016-01-01

    Hatching eggs, supplied to hatcheries are originating from different origins varying in breed, strain, and breeder age. These hatching eggs can be different in size, composition and eggshell properties, which might influence nutrient and O2 availability and consequently could affect embryonic

  16. The effect of egg versus seston quality on hatching success, naupliar metabolism and survival of Calanus finmarchicus in mesocosms dominated by Phaeocystis and diatoms

    DEFF Research Database (Denmark)

    Koski, Marja; Yebra, L.; Dutz, Jörg

    2012-01-01

    We studied the effect of a developing Skeletonema marinoi/Phaeocystis spp. bloom on Calanus finmarchicus hatching success, early naupliar survival and metabolism. Our focus was (1) on the development of reproductive rates during a bloom initiation, peak and decline in relation to the production o...

  17. How nest translocation-time, clutch size and presence of yolkless eggs affected hatching success in Dermochelys coriacea (Linnaeus, 1766 (Testudines: Dermochelyidae, at Projeto Tamar-Ibama, Espirito Santo, Brazil

    Directory of Open Access Journals (Sweden)

    Dal Pont Morisso, Eduardo

    2004-07-01

    Full Text Available En este estudio se analizó el manejo de los nidos de la especie Dermochelys coriacea, utilizados por el Proyecto Tamar-Ibama entre las temporadas reproductivas de 1989/1990 a 1998/1999, para verificación del éxito de la eclosión en relación a los tiempos de traslación. El estudio se realizó en el litoral norte del Estado de Espírito Santo. Existió tendencia a que el tiempo de traslación influencie el éxito de eclosión de los nidos. Los nidos trasladados entre 6 y más de 24 horas presentaron mayor cantidad de huevos sin desarrollo embrionario. No se encontró relación entre el número de huevos inviables trasladados y el tamaño de la postura, con el porcentual de eclosión. Se sugiere que la traslación sea realizada hasta las 6 horas, o 15 días después de la oviposición. The results of managing Dermochelys coriacea (Linnaeus, 1766 nests by Projeto TAMAR - IBAMA, in Northern Espírito Santo, Brazil, during the nesting seasons from 1989/90 to 1998/99 are analyzed. The influence of the translocation time on hatching success of the studied nests is discussed. The time translocation, in relation to natural oviposition, seems to increase the number of non-developed eggs found in each nest if translocated between 6 hours and 15 days post egg-laying. There was no relationship established between either the number of yolkless eggs in a translocated nest or the clutch size, with hatching success. The translocation of Dermochelys nests either within 6 hours or after 15 days from natural oviposition is recommended.

  18. Glassfrog embryos hatch early after parental desertion.

    Science.gov (United States)

    Delia, Jesse R J; Ramírez-Bautista, Aurelio; Summers, Kyle

    2014-06-22

    Both parental care and hatching plasticity can improve embryo survival. Research has found that parents can alter hatching time owing to a direct effect of care on embryogenesis or via forms of care that cue the hatching process. Because parental care alters conditions critical for offspring development, hatching plasticity could allow embryos to exploit variation in parental behaviour. However, this interaction of parental care and hatching plasticity remains largely unexplored. We tested the hypothesis that embryos hatch early to cope with paternal abandonment in the glassfrog Hyalinobatrachium fleischmanni (Centrolenidae). We conducted male-removal experiments in a wild population, and examined embryos' response to conditions with and without fathers. Embryos hatched early when abandoned, but extended development in the egg stage when fathers continued care. Paternal care had no effect on developmental rate. Rather, hatching plasticity was due to embryos actively hatching at different developmental stages, probably in response to deteriorating conditions without fathers. Our experimental results are supported by a significant correlation between the natural timing of abandonment and hatching in an unmanipulated population. This study demonstrates that embryos can respond to conditions resulting from parental abandonment, and provides insights into how variation in care can affect selection on egg-stage adaptations.

  19. Glassfrog embryos hatch early after parental desertion

    Science.gov (United States)

    Delia, Jesse R. J.; Ramírez-Bautista, Aurelio; Summers, Kyle

    2014-01-01

    Both parental care and hatching plasticity can improve embryo survival. Research has found that parents can alter hatching time owing to a direct effect of care on embryogenesis or via forms of care that cue the hatching process. Because parental care alters conditions critical for offspring development, hatching plasticity could allow embryos to exploit variation in parental behaviour. However, this interaction of parental care and hatching plasticity remains largely unexplored. We tested the hypothesis that embryos hatch early to cope with paternal abandonment in the glassfrog Hyalinobatrachium fleischmanni (Centrolenidae). We conducted male-removal experiments in a wild population, and examined embryos' response to conditions with and without fathers. Embryos hatched early when abandoned, but extended development in the egg stage when fathers continued care. Paternal care had no effect on developmental rate. Rather, hatching plasticity was due to embryos actively hatching at different developmental stages, probably in response to deteriorating conditions without fathers. Our experimental results are supported by a significant correlation between the natural timing of abandonment and hatching in an unmanipulated population. This study demonstrates that embryos can respond to conditions resulting from parental abandonment, and provides insights into how variation in care can affect selection on egg-stage adaptations. PMID:24789892

  20. Five-month comparative efficacy evaluation of three ectoparasiticides against adult cat fleas (Ctenocephalides felis), flea egg hatch and emergence, and adult brown dog ticks (Rhipicephalus sanguineus sensu lato) on dogs housed outdoors.

    Science.gov (United States)

    Varloud, Marie; Hodgkins, Elizabeth

    2015-03-01

    This study was designed to compare the efficacy of three topical combinations on dogs in outdoor conditions against adult cat fleas (Ctenocephalides felis), flea egg hatch and emergence, and against adult brown dog ticks (Rhipicephalus sanguineus sensu lato). Treatment was performed on day 0 with a placebo; dinotefuran, pyriproxifen and permethrin (DPP); fipronil and (S)-methoprene (FM) or imidacloprid and permethrin (IP). Dogs (n = 32), housed outdoors for 7 months, were treated monthly for four consecutive months (on days 0, 30, 60 and 90) and infested with ~100 unfed adult fleas on days 14, 55, 74, 115 and 150 and with ~50 unfed adult ticks on days 28, 44, 88 and 104. Adult fleas were counted and removed 24 h after infestation. Immediately after flea removal, dogs were reinfested with ~100 new adult fleas 72 h prior to egg collection for up to 48 h. Flea eggs were incubated for 32 days, and newly emerged adults were counted. Ticks were counted and removed 48 h after each infestation. FM had >90 % efficacy against fleas at each time point and variable efficacy against ticks (38.0-99.6 %). Efficacy of IP was 60 days after the last treatment. Despite challenging weather conditions, DPP was highly effective, providing >90 % efficacy against adult ticks as well as adult and immature fleas at every time point of the study.

  1. Review on the acute Daphnia magna toxicity test – Evaluation of the sensitivity and the precision of assays performed with organisms from laboratory cultures or hatched from dormant eggs

    Directory of Open Access Journals (Sweden)

    G. Persoone

    2009-08-01

    performance of the assays.One of these microbiotests is the Daphtoxkit F magna, which is currently used in many laboratories worldwide for research as well as for toxicity monitoring purposes.The microbiotest technology has several advantages in comparison to the “traditional” tests based on laboratory cultures, especially its independence of the stock culturing burden. However, the acceptance (or possible non-acceptance of performing assays with test organisms obtained from “dormant eggs” should be clearly dictated by the “sensitivity” and “precision” criteria of the former assays in comparison to the latter.The first part of this review therefore thoroughly reviews the scientific literature and of data obtained from various laboratories for assays performed with either D. magna test organisms obtained from lab cultures or hatched from dormant eggs.Attention has focused on data of quality control tests performed on reference chemicals, and in particular on potassium dichromate (K2Cr2O7 for which an acceptability range of 0.6–2.1 mg·L–1 has been set in ISO standard 6341 for the 24 h EC50 of the acute D. magna assay.Mean EC50s, standard deviations and variation coefficients were calculated from the collected data, all of which are presented in tables and figures and discussed in detail.The major conclusions drawn from the analysis of the large number of quality control (QC data on the acute D. magna toxicity test are that :(1 Virtually all results from assays performed with Daphnias taken from lab cultures or with Daphnia microbiotests are within the acceptability range set by ISO standard 6341 for the reference chemical potassium dichromate.(2 The mean 24 h EC50s of the Daphnia microbiotests performed in different laboratories are within the range of the mean EC50s of the assays based on lab cultures, and the variation coefficients (20 to 30% are similar.(3 The precision – in terms of the long term in house variability – of the quality control Daphnia

  2. The use of artificial spawning substrates in order to understand the factors influencing the spawning site selection, depth of egg strands deposition and hatching time of perch (Perca fluviatilis L.

    Directory of Open Access Journals (Sweden)

    Jan Kubečka

    2012-01-01

    Full Text Available The distribution of egg strands of perch Perca fluviatilis and factors affecting this distribution, in terms of spawning sites and spawning depths used, was studied in spring 2010 in Chabařovice Lake, Czech Republic, using areas with an artificial spawning substrate (A.S.S. and control areas outside the A.S.S. Perch significantly preferred a calm shore instead of a windward shore for spawning. The depths at which perch egg strands were found increased significantly during the spawning period in both A.S.S. areas and in areas outside the A.S.S. (on average from 4.9 m at the beginning to 12.3 m at the end of the spawning period. With increasing depth of deposition the size of the egg strands decreased significantly. The mean depth of egg strands on individual dates corresponded to the position of 10-12°C water layers. From the third week onward, however, egg strands were deposited in much deeper and colder water. A strong relationship was found between the depth at which egg strands were deposited and the duration of the daylight period, indicating that, at the end of the spawning season, perch do not react to the actual temperature of the water column but that they follow their inner clock, assuming that "normally" the shallower depth layers are too warm for successful embryo development. Factors influencing the depth distribution of egg strands were identified as waves, temperature and duration of the daylight period. Factors influencing the selection of spawning sites were identified as wind inducing current, internal seiches and temperature instability of the water column. The first perch larvae were present in the open water of Chabařovice Lake before mid-May, and the latest larvae not earlier than the beginning of July, since warming of the water in deeper layers was very slow. It appears that with prolonged spawning and hatching periods and with spawning occurring at various depths and temperatures, perch have evolved a powerful

  3. Cell lineages of the embryo of the nematode Caenorhabditis elegans.

    Science.gov (United States)

    Deppe, U; Schierenberg, E; Cole, T; Krieg, C; Schmitt, D; Yoder, B; von Ehrenstein, G

    1978-01-01

    Embryogenesis of the free-living soil nematode Caenorhabditis elegans produces a juvenile having about 550 cells at hatching. We have determined the lineages of 182 cells by tracing the divisions of individual cells in living embryos. An invariant pattern of cleavage divisions of the egg generates a set of stem cells. These stem cells are the founders of six stem cell lineages. Each lineage has its own clock--i.e., an autonomous rhythm of synchronous cell divisions. The rhythms are maintained in spite of extensive cellular rearrangement. The rate and the orientation of the cell divisions of the cell lineages are essentially invariant among individuals. Thus, the destiny of cells seems to depend primarily on their lineage history. The anterior position of the site of origin of the stem cells in the egg relates to the rate of the cell cycle clock, suggesting intracellular preprogramming of the uncleaved egg. We used a technique that allows normal embryogenesis, from the fertilized egg to hatching, outside the parent under a cover glass. Embryogenesis was followed microscopically with Nomarski interference optics and high-resolution video recording.

  4. Phytoseiid mites in protected crops: the effect of humidity and food availability on egg hatch and adult life span of Iphiseius degenerans, Neoseiulus cucumeris, N. californicus and Phytoseiulus persimilis (Acari: Phytoseiidae).

    Science.gov (United States)

    De Courcy Williams, Michael E; Kravar-Garde, Lidija; Fenlon, John S; Sunderland, Keith D

    2004-01-01

    The effect of relative humidity on egg hatch success for Iphiseius degenerans, Neoseiulus californicus and N. cucumeris was described by a binomial model with a parallel slope. The shape of the response differed for Phytoseiulus persimilis and a model with separate parameters gave a significantly better fit. Fitted response curves showed that I. degenerans, N. cucumeris, N. californicus and P. persimilis were ranked by decreasing tolerance to low humidity, with egg mortalities of persimilis egg duration was significantly longer at 60 and 70% than for either 82 or 90% RH. No effect of relative humidity was found on the mean life span of adult females when food was available continuously to the mites. N. californicus lived significantly longer (58 days after the first egg was laid) than the other species. No significant difference was observed in mean life span between adult females of I. degenerans and N. cucumeris (25 and 28 days respectively). The mean life span of adult female P. persimilis (19 days) was significantly shorter than the other species. In the absence of both food and water, the survival of adult female mites was reduced to 2-4 days. Survival time was at least doubled when free water was available in the absence of food. Mean survival of adult female mites with water but without food was 10 days for N. cucumeris, 18 days for N. californicus, 6 days for P. persimilis and 4 days for I. degenerans. Survival of adult female N. cucumeris and N. californicus was increased significantly, to 20 and 22 days respectively, when fungal hyphae were present along with water but in the absence of other food.

  5. A Comparative Study of Four Methods for the Detection of Nematode Eggs and Large Protozoan Cysts in Mandrill Faecal Material.

    Science.gov (United States)

    Pouillevet, Hanae; Dibakou, Serge-Ely; Ngoubangoye, Barthélémy; Poirotte, Clémence; Charpentier, Marie J E

    2017-01-01

    Coproscopical methods like sedimentation and flotation techniques are widely used in the field for studying simian gastrointestinal parasites. Four parasites of known zoonotic potential were studied in a free-ranging, non-provisioned population of mandrills (Mandrillus sphinx): 2 nematodes (Necatoramericanus/Oesophagostomum sp. complex and Strongyloides sp.) and 2 protozoan species (Balantidium coli and Entamoeba coli). Different coproscopical techniques are available but they are rarely compared to evaluate their efficiency to retrieve parasites. In this study 4 different field-friendly methods were compared. A sedimentation method and 3 different McMaster methods (using sugar, salt, and zinc sulphate solutions) were performed on 47 faecal samples collected from different individuals of both sexes and all ages. First, we show that McMaster flotation methods are appropriate to detect and thus quantify large protozoan cysts. Second, zinc sulphate McMaster flotation allows the retrieval of a higher number of parasite taxa compared to the other 3 methods. This method further shows the highest probability to detect each of the studied parasite taxa. Altogether our results show that zinc sulphate McMaster flotation appears to be the best technique to use when studying nematodes and large protozoa. © 2017 S. Karger AG, Basel.

  6. Biology and predatory attributes of a diplogasterid nematode, Fictor composticola Khan et al., 2008

    Directory of Open Access Journals (Sweden)

    Bajaj H. K.

    2015-02-01

    Full Text Available Biology of Fictor composticola has been studied on Aphelenchus avenae in vitro. It reproduces by amphimixis, embryonic development is completed in 24 - 27 h and life cycle in 3 - 4 days. Fusion of sperm and egg pronuclei occurs in the uteri. Pulsation of median oesophageal bulb and pressing of lips against egg shell is seen just prior to hatching but teeth seem to play no role in this process. No moulting occurs inside the egg shell and the first stage juvenile hatches out. Female and male undergo mating upon addition of water in the culture plates and continue to swim in copula for a considerable time. A female lays 1.6 - 4.0 eggs in 24 h while feeding upon A. radicicolus. Predation and reproduction is affected by the temperature and 25 - 35 °C is the optimum range for these phenomena. Process of feeding as recorded with a CCTV attached to a compound microscope is described. F. composticola engulfs small preys; sucks the intestinal contents while holding them or cuts the body wall of large-sized preys and then feeds on prolapsed organs. Two sexes differ in their efficiencies of predation, a female on an average kills 53 A. avenae as compared to 11 by a male in 24 h. F. composticola feeds and reproduces on mycophagous nematodes and juveniles of root- knot, cyst and citrus nematodes but does not prey upon adult nematodes having coarsely annulated cuticle. Cannibalism in this species is also observed. F. composticola and Seinura paratenuicaudata prey upon each other. Biocontrol potential of F. composticola for managing nematode problems in button mushroom and agricultural crops has also been discussed.

  7. Diet of two invading gobiid species (Proterorhinus semilunaris and Neogobius melanostomus) during the breeding and hatching season: No field evidence of extensive predation on fish eggs and fry

    Czech Academy of Sciences Publication Activity Database

    Vašek, Mojmír; Všetičková, Lucie; Roche, Kevin Francis; Jurajda, Pavel

    2014-01-01

    Roč. 46, March (2014), s. 31-36 ISSN 0075-9511 R&D Projects: GA ČR(CZ) GAP505/11/1768 Institutional support: RVO:68081766 Keywords : Invasive species * Trophic niche * Diet overlap * Egg predation * Competition * Ecological impact * Habitat modification Subject RIV: EG - Zoology Impact factor: 1.800, year: 2014

  8. Comparison of percent hatch and fungal infestation in channel catfish eggs after copper sulfate, diquat bromide, formalin, and hydrogen peroxide treatment

    Science.gov (United States)

    Reduced survival is often a result of fungal (Saprolegnia spp.) infestation of fish eggs. However, timely chemical treatments often limit these infestations and increase survival. The effect of copper sulfate pentahydrate (CSP - 10 mg/L), diquat bromide (25 mg/L diquat cation), formalin (433 mg/L)...

  9. Egg production and hatching success in the calanoid copepods Calanus helgolandicus and Calanus finmarchicus in the North Sea from March to September 2001

    DEFF Research Database (Denmark)

    Jonasdottir, Sigrun; Trung, N. H.; Hansen, F.

    2005-01-01

    of seston fatty acids. Seasonal and spatial distribution and production differed between the species. Calanus finmarchicus was found only offshore of the 50-m isobath, with decreasing E-r (37-28 eggs female(-1) day(-1)) from March to July. Calanus helgolandicus had two abundance peaks, in spring and autumn...

  10. Efficacy of ivermectin against gastrointestinal nematodes of cattle in Denmark evaluated by different methods for analysis of faecal egg count reduction

    Directory of Open Access Journals (Sweden)

    Miguel Peña-Espinoza

    2016-12-01

    Full Text Available The efficacy of ivermectin (IVM against gastrointestinal nematodes in Danish cattle was assessed by faecal egg count reduction test (FECRT. Six cattle farms with history of clinical parasitism and avermectin use were included. On the day of treatment (Day 0, 20 naturally infected calves per farm (total n = 120 were stratified by initial faecal egg counts (FEC and randomly allocated to a treatment group dosed with 0.2 mg IVM kg−1 body weight s.c. (IVM; n = 10 or an untreated control group (CTL; n = 10. Individual FEC were obtained at Day 0 and Day 14 post-treatment and pooled faeces by group were cultured to isolate L3 for detection of Ostertagia ostertagi and Cooperia oncophora by qPCR. Treatment efficacies were analysed using the recommended WAAVP method and two open-source statistical procedures based on Bayesian modelling: ‘eggCounts’ and ‘Bayescount’. A simulation study evaluated the performance of the different procedures to correctly identify FEC reduction percentages of simulated bovine FEC data representing the observed real data. In the FECRT, reduced IVM efficacy was detected in three farms by all procedures using data from treated animals only, and in one farm according to the procedures including data from treated and untreated cattle. Post-treatment, O. ostertagi and C. oncophora L3 were detected by qPCR in faeces of treated animals from one and three herds with declared reduced IVM efficacy, respectively. Based on the simulation study, all methods showed a reduced performance when FEC aggregation increased post-treatment and suggested that a treatment group of 10 animals is insufficient for the FECRT in cattle. This is the first report of reduced anthelmintic efficacy in Danish cattle and warrants the implementation of larger surveys. Advantages and caveats regarding the use of Bayesian modelling and the relevance of including untreated cattle in the FECRT are discussed.

  11. Efficacy of ivermectin against gastrointestinal nematodes of cattle in Denmark evaluated by different methods for analysis of faecal egg count reduction.

    Science.gov (United States)

    Peña-Espinoza, Miguel; Thamsborg, Stig M; Denwood, Matthew J; Drag, Markus; Hansen, Tina V; Jensen, Vibeke F; Enemark, Heidi L

    2016-12-01

    The efficacy of ivermectin (IVM) against gastrointestinal nematodes in Danish cattle was assessed by faecal egg count reduction test (FECRT). Six cattle farms with history of clinical parasitism and avermectin use were included. On the day of treatment (Day 0), 20 naturally infected calves per farm (total n = 120) were stratified by initial faecal egg counts (FEC) and randomly allocated to a treatment group dosed with 0.2 mg IVM kg -1 body weight s.c. (IVM; n = 10) or an untreated control group (CTL; n = 10). Individual FEC were obtained at Day 0 and Day 14 post-treatment and pooled faeces by group were cultured to isolate L3 for detection of Ostertagia ostertagi and Cooperia oncophora by qPCR. Treatment efficacies were analysed using the recommended WAAVP method and two open-source statistical procedures based on Bayesian modelling: 'eggCounts' and 'Bayescount'. A simulation study evaluated the performance of the different procedures to correctly identify FEC reduction percentages of simulated bovine FEC data representing the observed real data. In the FECRT, reduced IVM efficacy was detected in three farms by all procedures using data from treated animals only, and in one farm according to the procedures including data from treated and untreated cattle. Post-treatment, O. ostertagi and C. oncophora L3 were detected by qPCR in faeces of treated animals from one and three herds with declared reduced IVM efficacy, respectively. Based on the simulation study, all methods showed a reduced performance when FEC aggregation increased post-treatment and suggested that a treatment group of 10 animals is insufficient for the FECRT in cattle. This is the first report of reduced anthelmintic efficacy in Danish cattle and warrants the implementation of larger surveys. Advantages and caveats regarding the use of Bayesian modelling and the relevance of including untreated cattle in the FECRT are discussed. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All

  12. In vitro ovicidal and larvicidal activity of condensed tannins on gastrointestinal nematode infestations in sheep (Ovis aries

    Directory of Open Access Journals (Sweden)

    Eidi Yoshihara

    2014-12-01

    Full Text Available Infestations of gastrointestinal parasitic nematodes in sheep result in significant costs to farmers. These infestations are controlled using synthetic anthelmintic treatments, which can result in the development of anthelmintic resistance in nematodes. The use of plants rich in condensed tannins (CTs is a promising alternative for controlling infestations of harmful parasites in sheep, and could allow reduction of the chemical products used. This study investigated the in vitro effect of CTs from Acacia mearnsii extract (AE on egg hatching and motility of third-stage larvae. Egg-hatching rate was measured after incubation with extracts for 48 h at 27 °C. The egg hatch test was performed with dilutions of 0.09, 0.19, 0.39, 0.78, 1.56, 3.12, 6.25, 12.5, 25, 50, and 100 mg mL-1. Distilled water was used as the negative control. The corresponding egg hatching inhibition percentages were 22.3, 32.3, 39.2, 49.1, 56.7, 59.0, 62.3, 77.3, 92.7, 98.3, and 100%. The concentration required to inhibit egg hatching in 50% of eggs (LC50 was 2.85 mg mL-1. The inhibition achieved with the negative control was 7.06%. A larval migration inhibition test was carried out after incubation with the extracts for 48 h at 27 oC, with AE and distilled water used in dilutions of 3.12, 6.25, 12.5, 25, 50, and 100 mg mL-1. The corresponding percentages of migration inhibition were 16.5, 37.0, 56.3, 79.4, 91.8, and 97.1%. The concentration required to inhibit migration of 50% of larvae (LC50 was 12.45 mg mL-1. The inhibition achieved with the negative control was 8.53%. The in vitro ovicidal and larvicidal activity of CTs from AE indicate the anthelmintic effect of AE, suggesting the potential of CT extracts to be used as alternatives for controlling gastrointestinal nematode infestations in small ruminants.

  13. Anthelmintic activity of Cocos nucifera L. against sheep gastrointestinal nematodes.

    Science.gov (United States)

    Oliveira, L M B; Bevilaqua, C M L; Costa, C T C; Macedo, I T F; Barros, R S; Rodrigues, A C M; Camurça-Vasconcelos, A L F; Morais, S M; Lima, Y C; Vieira, L S; Navarro, A M C

    2009-01-22

    The development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. Among these alternatives are several medicinal plants traditionally used as anthelmintics. This work evaluated the efficacy of Cocos nucifera fruit on sheep gastrointestinal parasites. The ethyl acetate extract obtained from the liquid of green coconut husk fiber (LGCHF) was submitted to in vitro and in vivo tests. The in vitro assay was based on egg hatching (EHT) and larval development tests (LDT) with Haemonchus contortus. The concentrations tested in the EHT were 0.31, 0.62, 1.25, 2.5 and 5 mg ml(-1), while in the LDT they were 5, 10, 20, 40 and 80 mg ml(-1). The in vivo assay was a controlled test. In this experiment, 18 sheep infected with gastrointestinal nematodes were divided into three groups (n=6), with the following doses administered: G1-400 mg kg(-1) LGCHF ethyl acetate extract, G2-0.2 mg kg(-1) moxidectin (Cydectin) and G3-3% DMSO. The worm burden was analyzed. The results of the in vitro and in vivo tests were submitted to ANOVA and analyzed by the Tukey and Kruskal-Wallis tests, respectively. The extract efficacy in the EHT and LDT, at the highest concentrations tested, was 100% on egg hatching and 99.77% on larval development. The parameters evaluated in the controlled test were not statistically different, showing that despite the significant results of the in vitro tests, the LGCHF ethyl acetate extract showed no activity against sheep gastrointestinal nematodes.

  14. Egg temperature and embryonic metabolism of A- and B-eggs of ...

    African Journals Online (AJOL)

    Macaroni and rockhopper penguins lay two eggs but rear only one chick to independence. The eggs are markedly dimorphic in size and, although the smaller A-egg is laid several days before the B-egg, in nests where both eggs are incubated, the B-egg always hatches first. Incubation temperatures and embryonic oxygen ...

  15. The diverse nematicidal properties and biocontrol efficacy of Bacillus thuringiensis Cry6A against the root-knot nematode Meloidogyne hapla.

    Science.gov (United States)

    Yu, Ziquan; Xiong, Jing; Zhou, Qiaoni; Luo, Haiyan; Hu, Shengbiao; Xia, Liqiu; Sun, Ming; Li, Lin; Yu, Ziniu

    2015-02-01

    Cry6A toxin from Bacillus thuringiensis is a representative nematicidal crystal protein with a variety of nematicidal properties to free-living nematode Caenorhabditis elegans. Cry6A shares very low homology and different structure with Cry5B, another representative nematicidal crystal protein, and probably acts in a distinct pathway. All these strongly indicate that Cry6A toxin is likely a potent candidate for nematicide. The present study dealt with global investigation to determine the detrimental impacts of Cry6Aa2 toxin on Meloidogyne hapla, a root-knot nematode, and evaluated its biocontrol efficacy in pot experiment. Obtained results indicated that Cry6Aa2 toxin exhibits obvious toxicity to second-stage juvenile of M. hapla, and significantly inhibits egg hatch, motility, and penetration to host plant. Pot experiment suggested that soil drenching with spore-crystal mixture of Cry6Aa2 can clearly lighten the disease of root-knot nematode, including reduction of galling index and egg masses on host plant root, decreasing final population of nematode in soil. Moreover, application of Cry6Aa2 can obviously promote plant growth. These results demonstrated that Cry6Aa2 toxin is a promising nematicidal agent, and possesses great potential in plant-parasitic nematode management and construction of transgenic crop with constant resistance to nematode. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Ovulation order mediates a trade-off between pre-hatching and post-hatching viability in an altricial bird.

    Directory of Open Access Journals (Sweden)

    Keith W Sockman

    2008-03-01

    Full Text Available Simultaneously dependent siblings often compete for parentally provided resources. This competition may lead to mortality, the probability of which may be a function, in part, of the individual offspring's production order. In birds, serial ovulation followed by hatching asynchrony of simultaneous dependents leads to differences in post-hatching survival that largely depend on ovulation (laying order. This has led to the widespread assumption that early-laid eggs are of greater value and therefore should possess different maternally manipulated characteristics than later-laid eggs. However, this perspective ignores the potential effect of laying order on pre-hatching viability, an effect which some studies suggest should offset the effect of laying order on post-hatching viability. I examined the relationship between laying order and hatching and fledging probability in wild, free-living Lincoln's sparrows (Melospiza lincolnii. In broods with complete hatching success, first-laid and therefore first-hatched offspring had the highest probability of fledging, and fledging probability declined with increasing laying order. However, first-laid eggs were less likely than later-laid eggs to hatch. This effect of laying order on pre-hatching viability seemed to offset that on post-hatching viability, and, consistently, maternal investment in egg size varied little if at all with respect to laying order. These results suggest that ovulation order mediates a trade-off between pre-hatching and post-hatching viability and should encourage a re-evaluation of the solitary role post-embryonic survival often plays when researchers make assumptions about the value of propagules based on the order in which they are produced.

  17. Effects of Different Hatcher Temperatures on Hatching Traits of ...

    African Journals Online (AJOL)

    selcuk

    of genetic improvements in the modern broilers, the incubation conditions and ... development of the different organs and body structures of the embryo in time, and .... (hatching time, hatchability of fertile eggs, mortality stages and embryo ...

  18. Extended phenotype: nematodes turn ants into bird-dispersed fruits

    DEFF Research Database (Denmark)

    Hughes, D P; Kronauer, D J C; Boomsma, J J

    2008-01-01

    A recent study has discovered a novel extended phenotype of a nematode which alters its ant host to resemble ripe fruit. The infected ants are in turn eaten by frugivorous birds that disperse the nematode's eggs.......A recent study has discovered a novel extended phenotype of a nematode which alters its ant host to resemble ripe fruit. The infected ants are in turn eaten by frugivorous birds that disperse the nematode's eggs....

  19. Studies on Lasioseius scapulatus, a Mesostigmatid mite predaceous on nematodes

    OpenAIRE

    Imbriani, I.; Mankau, R.

    1983-01-01

    The life history and feeding habits of Lasioseius scapulatus, an ascid predator and potential biocontrol agent of nematodes, was examined. Reproduction was asexual, and the life cycle was 8-10 days at room temperature. Life history consisted of the egg, protonymph, deutonymph, and adult. Both nymphal stages and the adult captured and consumed nematodes. Two fungal genera and eight genera of nematodes were suitable food sources. Second-stage root-knot nematode juveniles were eaten, but eggs an...

  20. Extracellular Protease of Pseudomonas fluorescens CHA0, a Biocontrol Factor with Activity against the Root-Knot Nematode Meloidogyne incognita

    OpenAIRE

    Siddiqui, Imran Ali; Haas, Dieter; Heeb, Stephan

    2005-01-01

    In Pseudomonas fluorescens CHA0, mutation of the GacA-controlled aprA gene (encoding the major extracellular protease) or the gacA regulatory gene resulted in reduced biocontrol activity against the root-knot nematode Meloidogyne incognita during tomato and soybean infection. Culture supernatants of strain CHA0 inhibited egg hatching and induced mortality of M. incognita juveniles more strongly than did supernatants of aprA and gacA mutants, suggesting that AprA protease contributes to biocon...

  1. Extracellular Protease of Pseudomonas fluorescens CHA0, a Biocontrol Factor with Activity against the Root-Knot Nematode Meloidogyne incognita

    Science.gov (United States)

    Siddiqui, Imran Ali; Haas, Dieter; Heeb, Stephan

    2005-01-01

    In Pseudomonas fluorescens CHA0, mutation of the GacA-controlled aprA gene (encoding the major extracellular protease) or the gacA regulatory gene resulted in reduced biocontrol activity against the root-knot nematode Meloidogyne incognita during tomato and soybean infection. Culture supernatants of strain CHA0 inhibited egg hatching and induced mortality of M. incognita juveniles more strongly than did supernatants of aprA and gacA mutants, suggesting that AprA protease contributes to biocontrol. PMID:16151170

  2. Oxfendazole Resistance in Gastrointestinal Nematodes of Beetal Goats at Livestock Farms of Punjab (Pakistan

    Directory of Open Access Journals (Sweden)

    M. Saeed

    2007-01-01

    Full Text Available This study was carried out to screen goat farms for anthelmintic resistance (AR against oxfendazole (OXF and to determine contributory factors for its development. For this purpose, Beetal goat farms (n = 18 were randomly selected, with natural mixed gastrointestinal nematodosis infection. In vivo (faecal egg count reduction test and in vitro (egg hatch assay tests were used to ascertain the presence of AR while a scorecard was used to determine the role of possible contributory factors for oxfendazole resistance. For in vivo test, the experimental animals were divided into two groups of 10 animals each; one group received OXF treatment, while the other served as control. Pre- and post-treatment coproculture was performed to identify the species and genera of nematodes. Egg hatch assay (EHA was used to confirm the results of FECRT. Fecal egg count reduction test (FECRT revealed the development of resistance on six farms and post-treatment larval cultures indicated Haemonchus contortus, Trichostrongylus colubriformis, Cooperia curticei, Teladorsagia circumcincta and Oesophagostomum spp. as dominant species with resistance. Furthermore, EHA confirmed the results of FECRT. Among the presumptive factors for AR, the highest composite score was for rotation of anthelmintics followed by treatment frequency, dose rate and nature of medication. The scorecard for the development of AR, used in this study, may be helpful for the assessment of contributory factors of AR.

  3. Hatching the behavioral addiction egg: Reward Deficiency Solution System (RDSS)™ as a function of dopaminergic neurogenetics and brain functional connectivity linking all addictions under a common rubric.

    Science.gov (United States)

    Blum, Kenneth; Febo, Marcelo; McLaughlin, Thomas; Cronjé, Frans J; Han, David; Gold, S Mark

    2014-09-01

    Following the first association between the dopamine D2 receptor gene polymorphism and severe alcoholism, there has been an explosion of research reports in the psychiatric and behavioral addiction literature and neurogenetics. With this increased knowledge, the field has been rife with controversy. Moreover, with the advent of Whole Genome-Wide Studies (GWAS) and Whole Exome Sequencing (WES), along with Functional Genome Convergence, the multiple-candidate gene approach still has merit and is considered by many as the most prudent approach. However, it is the combination of these two approaches that will ultimately define real, genetic allelic relationships, in terms of both risk and etiology. Since 1996, our laboratory has coined the umbrella term Reward Deficiency Syndrome (RDS) to explain the common neurochemical and genetic mechanisms involved with both substance and non-substance, addictive behaviors. This is a selective review of peer-reviewed papers primary listed in Pubmed and Medline. A review of the available evidence indicates the importance of dopaminergic pathways and resting-state, functional connectivity of brain reward circuits. Importantly, the proposal is that the real phenotype is RDS and impairments in the brain's reward cascade, either genetically or environmentally (epigenetically) induced, influence both substance and non-substance, addictive behaviors. Understanding shared common mechanisms will ultimately lead to better diagnosis, treatment and prevention of relapse. While, at this juncture, we cannot as yet state that we have "hatched the behavioral addiction egg", we are beginning to ask the correct questions and through an intense global effort will hopefully find a way of "redeeming joy" and permitting homo sapiens live a life, free of addiction and pain.

  4. Incubação artificial dos ovos e processo de eclosão em Trachemys dorbignyi (Duméril & Bibron (Reptilia, Testudines, Emydidae Artificial egg incubation and hatching proccess in Trachemys dorbignyi (Duméril & Bibron (Reptilia, Testudimes, Emydidae

    Directory of Open Access Journals (Sweden)

    Flavio de Barros Molina

    1998-01-01

    Full Text Available Artificial incubation of 558 eggs from 70 clutches of Trachemys dorbignyi (Duméril & Bibron, 1835 were performed at São Paulo Zoo during 1992 and 1993. Hatching occurred when eggs were incubated between 25 and 31.5oC. Incubation time varied from 54 (at 31.5oC to 120 days (at 25oC, similarly to Trachemys scripla sspp. Hatchling used the caruncle to made small incisions in the egg shell, latter enlarged by movements of the head and forefeet. Hatching usually lasted from one to two days. Newborn's carapace and plastron showed their natural form few hours after the emergence from the egg shell. During the third or fourth week, caruncle usually disappeared, and yolk sac was completely absorbed. Average (x±sd measures of newborn were 3.55±0.18cm of carapace length, 3.35±0.17cm of plastron length, and 10.73±1.36g of weight.

  5. Effect of castor bean (Ricinus communis L.) aqueous extracts on the performance of root-knot nematodes (Meloidogyne spp.) on tomato (Solanum lycopersicum L.)

    International Nuclear Information System (INIS)

    Adomako, J.; Kwoseh, C. K.

    2013-01-01

    The increased concern for environmental and health hazards have called for a reduction in the use of synthetic nematicides for nematode control. Experiments were, therefore, conducted to ascertain the nematicidal potential of castor bean's crude extract and its five lower concentrations with water as control. In the in vitro studies, crude castor bean aqueous extract and 10, 20, 30 and 40% different concentrations with 100 root-knot nematode eggs or juveniles in separate Petri dishes showed that all the different concentrations had toxic effects on eggs and juveniles of root-knot nematode. Egg hatch inhibition and juvenile mortality increased with increased concentration of the extracts. With an increase in exposure time, juvenile mortality increased. In potted plant studies, crude castor bean aqueous extracts and its lower concentrations of 20, 40 and 60% caused significant improvement in plant growth measures such as height and fresh shoot weight over the water blank control. The crude castor bean extract was nematotoxic to root -knot nematodes in vitro and in potted-tomato plants, but this was not demonstrated in field studies. Further work needs to be done before a firm recommendation can be made. (au)

  6. Anthelmintic activity of Trianthema portulacastrum L. and Musa paradisiaca L. against gastrointestinal nematodes of sheep.

    Science.gov (United States)

    Hussain, Altaf; Khan, Muhammad Nisar; Iqbal, Zafar; Sajid, Muhammad Sohail; Khan, Muhammad Kasib

    2011-06-30

    Evaluation of anthelmintic effects of Trianthema (T.) portulacastrum L. (Aizoaceae) whole plant and Musa (M.) paradisiaca L. (Musaceae) leaves against prevalent gastrointestinal worms of sheep was done that may justify their traditional use in veterinary clinical medicine. In vitro anthelmintic activity of the crude aqueous methanolic extract (CAME) of both the plants was determined using mature female Haemonchus (H.) contortus and their eggs in adult motility assay (AMA) and egg hatch test (EHT), respectively. In vivo anthelmintic activity of crude powder (CP) and CAME in increasing doses (1.0-8.0 g kg(-1)) was determined in sheep naturally infected with mixed species of nematodes using fecal egg count reduction test (FECRT) and larval counts. The study design also included untreated as well as treated controls. Fecal egg count reduction and larval counts from coprocultures were performed pre- and post-treatments to assess the anthelmintic activity of the plants. CAME of T. portulacastrum and M. paradisiaca showed a strong in vitro anthelmintic activity and pronounced inhibitory effects on H. contortus egg hatching as observed through AMA and EHT, respectively. Both plants exhibited dose and time dependent anthelmintic effects on live worms as well as egg hatching. M. paradisiaca (LC(50)=2.13 μg mL(-1)) was found to be more potent than T. portulacastrum (LC(50)=2.41 μg mL(-1)) in EHT. However, in vivo, maximum reduction in eggs per gram (EPG) of faeces was recorded as 85.6% and 80.7% with CAME of T. portulacastrum and M. paradisiaca at 8.0 g kg(-1) on 15th day post-treatment, respectively as compared to that of Levamisole (7.5 mg kg(-1)) that caused 97.0% reduction in EPG. All the species of gastrointestinal nematodes (GINs), i.e. Haemonchus contortus, Trichostronglyus spp., Oesophagostomum columbianum and Trichuris ovis which were prevalent, found susceptible (Pparadisiaca possess strong anthelmintic activity in vitro and in vivo, thus, justifying their use in

  7. Modeling winter moth Operophtera brumata egg phenology

    NARCIS (Netherlands)

    Salis, Lucia; Lof, Marjolein; Asch, van Margriet; Visser, Marcel E.

    2016-01-01

    Understanding the relationship between an insect's developmental rate and temperature is crucial to forecast insect phenology under climate change. In the winter moth Operophtera brumata timing of egg-hatching has severe fitness consequences on growth and reproduction as egg-hatching has to match

  8. Diapause in Calanoid Copepods: within-clutch hatching patterns

    Directory of Open Access Journals (Sweden)

    Bart T. DE STASIO

    2004-09-01

    Full Text Available Diapause is a major life history feature of many invertebrate organisms. Determining the phenology of diapause is critical for understanding survival and reproductive success of individuals as well as the long-term viability of many populations. The time spent in dormancy by individuals and variability among offspring in the duration of dormancy are two important aspects of invertebrate life histories. Some data are available, especially on duration of diapause, for plants and insects, but little information is available concerning variability among offspring in diapause traits. This is especially true for crustacean zooplankton, where essentially no information has been published on duration of diapause or variability among offspring in diapause timing or dynamics. Here I present data on the duration of diapause, and variability among offspring for diapause characteristics. The freshwater calanoid copepod Onychodiaptomus sanguineus, an obligately sexual species, was collected from Bullhead Pond, Rhode Island, U.S.A., and raised under conditions in the laboratory to induce production of diapausing eggs. One hundred clutches of these diapausing eggs (920 total eggs were incubated for over two years in a full-factorial experiment testing the effects of temperature and photoperiod cycles on the hatching dynamics and duration of diapause. Overall hatching success was highest (approximately 86% for eggs exposed to simultaneous temperature and photoperiod cycles mimicking natural changes, and was lowest (approximately 20% when eggs were incubated at constant temperature (4 °C and in constant dark conditions. The highest fraction of eggs hatched at approximately 550 days of age, but the age of eggs at hatching was highly variable among clutches. There was also large variability within clutches for hatching patterns, with some clutches containing eggs that all hatched synchronously and others in which eggs hatched more continuously throughout the

  9. Antagonistic Activities of Streptomyces against Root Knot Nematode of Kiwifruit

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    S. Bashiri

    2016-02-01

    into counting Petri plate and examined under a stereomicroscope. Nematode larvae were identified to generic level and were counted. Evaluation of Actinomycetes isolates against root-knot nematodes in vitro performed according to Sun et al. Seedlings (Six-month-old of kiwifruit (Actinidia deliciosa were sown in 30 cm3 pots containing autoclaved sandy loam soil (1:1. Pots were divided into three groups by three replicates. Bioagents were individually incorporated into the soil at a dose rate of 10 cm3 (Heavy cell suspension of all isolates was prepared at rate 105 spores ml-1 were added to the soil. After seven days, (when bacterial cells reach its maximum growth peak plants were inoculated with 2000 freshly hatched second stage juveniles(J2 of Meloidogyne spp. Pots were fertilized with recommended dose and kept at 25ºC ± 3ºC in complete randomized design. After two months plants were uprooted then galls and egg masses were counted and their indices were recorded according to Sharma et al. Fresh weight of roots was also registered. Treatments means were compared by the Duncan Multiple Range Test at 0.05 level of probability. The growth responses of kiwifruit (roots weight and number of galls and egg mass were also recorded. Statistical analyses were achieved using SAS. Results and Discussion: Among 25 isolates identified as Streptomyces genus, 9 Actinomycetes isolates showed the antagonistic potential in vitro and reduced the rate of egg hatching in seven days and larval mortality in four days. Streptomyces sp3. Streptomyces sp4., Streptomyces sp5., Streptomyces sp9. And Streptomyces sp12. were able to reduce egg hatching 16.29%, 19.99%, 27.11%, 20.22% and 18.41% and increased the percentage of larval mortality 45%, 33.3%, 37.53%,35.01% and 37.50%, respectively. They showed the greatest effect and selected for evaluating in greenhouse condition. In addition, Streptomyces sp9.and Streptomyces sp4. reduced galls by 65.35% and 64.56% compared with the phenamiphus 57

  10. IN VITRO ANTHELMINTIC EFFECT OF METHANOLIC LEAF EXTRACT OF Gliricidia sepium AGAINST GASTROINTESTINALE NEMATODES OF SHEEP

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    Manuel Mateo Hernandez-Villegas

    2014-04-01

    Full Text Available The use of local resources for food and health care of animals is a highly profitable and sustainable strategy. Among these resources are native trees and shrubs which in addition to providing good quality nutrients, produce secondary metabolites with anthelmintic (AH effect. Therefore the aim of this study was to evaluate the in vitro AH effect of Gliricidia sepium leaves methanol extract (GSME, through the egg hatch inhibition assay (EHA. Three concentrations of the extracts were tested: 125, 250 and 500 μg/mL.  Also a negative control (distilled water and a positive control (levamisole 2 mg/mL were included. The GSME showed significant differences P<0.05 when compared with the positive control. The GSME also showed a dose-dependent response in inhibition of eggs hatching. Effectiveness percentages found were: 27.7%, 46.2%, 49.7% of inhibition at 125, 250, and 500 μg/mL respectively. The average dose (ED50 obtained through probit analysis was 394.96 μg/mL. These results suggest that the ME of leaves of G. sepium has anthelmintic activity against eggs of gastrointestinal nematodes.

  11. Anthelmintic effect of thymol and thymol acetate on sheep gastrointestinal nematodes and their toxicity in mice

    Directory of Open Access Journals (Sweden)

    Weibson Paz Pinheiro André

    Full Text Available Abstract Thymol is a monoterpene and acetylation form of this compound can reduce the toxicity and enhance its biological effects. The objective of this study was to evaluate the effect of thymol and thymol acetate (TA on egg, larva and adult Haemonchus contortus and the cuticular changes, acute toxicity in mice and the efficacy on sheep gastrointestinal nematodes. In vitro tests results were analyzed by analysis of variance (ANOVA and followed by comparison with Tukey test or Bonferroni. The efficacy of in vivo test was calculated by the BootStreet program. In the egg hatch test (EHT, thymol (0.5 mg/mL and TA (4 mg/mL inhibited larval hatching by 98% and 67.1%, respectively. Thymol and TA (8 mg/mL inhibited 100% of larval development. Thymol and TA (800 µg/mL reduced the motility of adult worms, by 100% and 83.4%, respectively. Thymol caused cuticular changes in adult worm teguments. In the acute toxicity test, the LD50 of thymol and TA were 1,350.9 mg/kg and 4,144.4 mg/kg, respectively. Thymol and TA reduced sheep egg count per gram of faeces (epg by 59.8% and 76.2%, respectively. In in vitro tests thymol presented better anthelmintic activity than TA. However TA was less toxic and in in vivo test efficacy was similar.

  12. The prevalence of gastrointestinal nematode infection and their ...

    African Journals Online (AJOL)

    GIN infection was associated with 1.4 litres per cow per day less milk and this ... Gastrointestinal nematode (GIN) infections in cattle are of considerable economic importance .... Table 2. Mean faecal egg counts of gastrointestinal nematodes and the 95% confidence ... 3.2 Gastrointestinal nematode species. The pooled ...

  13. Broiler adaptation to post-hatching period

    Directory of Open Access Journals (Sweden)

    Maiorka Alex

    2006-01-01

    Full Text Available In the latest years more attention has been given to mechanisms for bird adaptation at post-hatching period by management of environmental conditions and formulations of diets offered during this period when digestive, immune, and thermo-regulating systems suffer slight changes. In post-hatching period, digestive system is anatomically complete, but its functionality is still immature in relation to adult birds. The chick immunity depends on maternal antibodies transferred to egg just before laying. In addition, variations within thermal comfort zone might affect initial development of chick. For example, high temperatures may induce hyperthermia with dehydration, while low temperatures may lead to hypothermia responsible by pulmonary hypertension syndrome. In conclusion, productivity might be enhanced when good conditions are offered to chicks during the period from last embryo development to first days after hatching.

  14. In Vitro Pharmacodynamics of Benzimidazole and Tetrahydropyrimidine Derivatives in European Bison Gastro-Intestinal Nematodes

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    Laura CĂTANĂ

    2017-11-01

    Full Text Available The present study was aimed to evaluate the efficacy of anthelmintic agents against intestinal nematodes found in European bison. It was performed between October 2016 and May 2017, using Egg Hatch Assay (EHA and Larval Development Assay (LDA. The parasites were obtained from faecal samples, harvested from bisons in Romania and Sweden. The efficacy of albendazole (ABZ, mebendazole (MBZ thiabendazole (TBZ and pyrantel (PYR was tested. In EHA, the maximum efficacy was observed in MBZ (EC50 = - 0.227 μg/ml, and then TBZ (EC50 = - 0.2228. ABZ had a weaker result, EC50 being 0.326 μg/ml. All tested benzimidazoles registered hatching percentages below 50%, reflecting the lack of parasitic resistance. MIC obtained in the LDA tests were 0.2144 μg/ml for TBZ, 0.2792 μg/ml for PYR, 0.5429 μg/ml for MBZ, while ABZ came last (MIC = 0.8187 μg/ml. The in vitro tests proved the antiparasitic molecules efficacy against bisons nematode population and a limited risk of inducing resistance phenomena.

  15. Natural product synthesis: Making nematodes nervous

    Science.gov (United States)

    Snyder, Scott A.

    2011-06-01

    A highly inventive route for the synthesis of a key substance that stimulates potato cyst nematodes to hatch has been developed. This discovery has potential to impact food supplies, as treatment of crops with this compound could alleviate the devastating effect of these parasites.

  16. A refratariedade das aves ao "Trypanosoma (Schizotrypanum cruzi" II - refratariedade das galinhas desde o nascimento; persistência da refratariedade após Bursectomia; infecções em ovos embrionados The refractory state of birds toward the Trypanosoma (Schizotrypanum cruzi: II - the refractory state begins at hatching and persists after bursectomy, Infections of embryonnated eggs

    Directory of Open Access Journals (Sweden)

    F. Nery-Guimarães

    1972-01-01

    Full Text Available "A refratariedade das galinhas ao T. (S. cruzi, ocorre desde o nascimento e não é eliminada pela bursectomia hormonal. Noventa e oito pintos de 1 a 15 dias de vida (normais ou tratados com testosterona inoculados com o T. (S. cruzi foram negativos. Deste modo, dificilmente a refratariedade poderia ser interpretada como decorrência de um "anticorpo natural", uma vez que a bursectomia provoca uma queda na produção de anticorpos e das gamaglobulinas. Em cerca de 50% de ovos embrionados (normais ou tratados com o hormônio foram vistos flagelados do 4º ao 12º dia de inoculação, observando-se ninhos de amastigotos em alguns embriões. Os pintos nascidos dos mesmos grupos dos ovos examinados e positivos, foram sistematicamente negativos pelo exame do sangue. Um deles sacrificado horas depois de nascido, mostrou amastigotos no coração, mas esses parasitos pareciam degenerados. Provavelmente, se alguns chegam a evoluir para tripomastigotos, estes são destruídos á medida que as células hospedeiras se rompem, e assim jamais são encontrados no sangue circulante.It has already been shown that the refractory state of chickens toward "T. (S. cruzi" appears early at time of hatch. Fifty-four normal newly hatched and inoculated chicks were negative. it has also been verified that this refractory state persists even after hormonal bursectomy (eggs being injected with 2.5 mg of testosterone. Forty-four bursectomized and inoculated newly hatched chicks were negative. If we consider the fact that bursectomy causes a deficiency in the production of antibodies and gammaglobulins, the refractory state seems not to occur on account of a "natural antibody". Inoculations of "T. (S. cruzi" made in 153 eggs (normal or treated with testosterone produced infections of variable intensity in about 50% of them. Although chicks newly hatched from the same groups were always negative. As we have some embryos to be positive until the 21st day of incubation it seems

  17. MATHEMATICAL MODELING OF ELECTRO TECHNOLOGICAL OZONIZATION OF EGG STORES OF POULTRY FARMS

    OpenAIRE

    Voloshin A. P.

    2016-01-01

    Sanitization of eggs is an essential way to fight bacteria, fungi and other microorganisms. Hatchability of eggs and the safety of day-old chicks are dependent on the quality of eggs processing. Leading scientists of our country have proved high efficacy of ozone application for processing of hatching eggs. To obtain a positive result by this method of sanitizing hatching eggs ozone, it is necessary to create a uniform concentration of ozone around the egg store volume. Decrease in ozone conc...

  18. Ovicidal activity of succinic acid isolated from sisal waste (Agave sisalana against gastrointestinal nematodes of goats

    Directory of Open Access Journals (Sweden)

    Nathália Silva de Souza Santos

    Full Text Available ABSTRACT: This study was conducted to evaluate the in vitro anthelmintic activity of the succinic acid (SA isolated from sisal waste against gastrointestinal nematodes of goats, using the egg hatching and larvae motility assays. In addition, potential cytotoxicity of SA on Vero cell cultures was investigated by means of MTT (3-4,5-dimethylthiazol-2-yl, 2,5diphenyltetrazolium bromide test. The SA induced a significant inhibition of egg hatching (P<0.05 at all concentrations tested (60 to 250µg mL-1, and the concentrations to inhibit 50% (EC50 and 90% (EC90 values (mean ± standard deviation were 90.3±2.8 and 130.6±3.5µg mL-1, respectively. The SA has not shown larvicidal activity. The SA was less toxic to the Vero cells, with the mean percentage of cell viability equal to 85±6.2% at the concentration of 130µg mL-1. The results suggested that SA has potential anthelmintic effect; although, more research is needed to confirm its activity in vivo.

  19. Study the Effect of Three Species of Medicinal Plants of the Mint Family on Pathogenicity and Damage Root Knot Nematode Meloidogyne javanica in Tomato

    Directory of Open Access Journals (Sweden)

    Maryam Fayaz

    2017-03-01

    , and savory are pathogenic nematode damage in tomato was examined. Materials and Methods: In this study, the effect of the medicinal plants of the mint family on root knot nematode, three herb thyme (Thymus vulgaris, savory (Sature jahortensis and hyssop (Hyssopus officinalis was used. In order to prepare the inoculum required for the test, root-knot nematode- contaminated tomato samples were collected from the farms or greenhouses of Chaharmahal Bakhtiari Province (one of the provinces of Iran. To separate and extract eggs and larvae, contaminated roots were chopped into 1-2 cm pieces by the method of Hussey & Jonsen were mixed in 10% hypochlorite sodium solution in a mixer for one minute. Then the mixture was put in the 400-mesh sieve under water current so as to remove hypochlorite sodium. Finally, the eggs were collected in distilled water. Furthermore, to prepare sufficient larvae, nematode egg masses were transferred to petri dishes and kept in the incubator for 24 hours until the eggs hatched. Finally, the obtained eggs and larvae were used to carry out the test. A greenhouse experiment was as factorial in a completely randomized design with single culture tomato and mixed with herbal hyssop (Hyssopus officinalis, thyme (Thymus vulgaris, and savory (Sature sp, in the presence and absence of nematodes. Results and Discussion: The tomato growth parameters (dry weight of root, stem, leaf, root length, shoot length and nematode pathogenicity (Number of galls, egg massesin1/g of root of ,the number of eggs in each egg masses, second instar larvae per 100 gr of soil and reproductive factors were evaluated three months after nematode inoculations. Data were analyzed using SAS statistical software comparing MSTATC software and LSD test was performed. Statistical analysis of data showed the significance difference between treatments. ANOVA results demonstrated that the use of three species of medicinal plants of the mint family is a significant effect on the

  20. Effects of gamma radiation on codling moth, Cydia pomonella (L.), eggs

    International Nuclear Information System (INIS)

    Mansour, M.; Mohamad, F

    2005-01-01

    The radiosensitivity of codling moth, Cydia pomonella (L.), eggs in different stages of development was studied. Eggs ranging in age from 1-24 to 97-120 h were exposed, at 24 h intervals, to gamma radiation doses ranging from 10 to 350 Gy. The effects of gamma radiation on egg hatch, pupation and adult emergence was examined. Results showed that the radiosensitivity of codling moth eggs decreased with increasing age. Egg hatch in 1-24 h old eggs was significantly affected at 20 Gy dose and at 60 Gy dose, egg hatch decreased to about 1%. At the age of 25-48 h, however, egg hatch at 60 Gy dose was about 10%, and egg sensitivity to gamma irradiation decreased significantly in the 49-72 h age group; 60 Gy dose had no significant effect on egg hatch. Eggs irradiated few hours before hatch (at the blackhead stage), were the most resistant ones; 100 Gy had no significant effect on egg hatch and at 350 Gy dose over 56% of the eggs hatched. When adult emergence was used as a criterion for measuring effectiveness, however, the effect of gamma radiation was very sever. A dose of 60 Gy completely prevented adult emergence and at 100 Gy dose all resulted larvae died before pupation. (Author)

  1. Effects of gamma radiation on codling moth, Cydia pomonella (L.), eggs

    International Nuclear Information System (INIS)

    Mansour, M.; Mohamad, F.

    2004-01-01

    The radiosensitivity of codling moth, Cydia pomonella (L.), eggs in different stages of development was studied. Eggs ranging in age from 1-24 to 97-120 h were exposed, at 24 h intervals, to gamma radiation doses ranging from 10 to 350 Gy. The effects of gamma radiation on egg hatch, pupation and adult emergence was examined. Results showed that the radiosensitivity of codling moth eggs decreased with increasing age. Egg hatch in 1-24 h old eggs was significantly affected at 20 Gy dose and at 60 Gy dose, egg hatch decreased to about 1%. At the age of 25-48 h, however, egg hatch at 60 Gy dose was about 10%, and egg sensitivity to gamma irradiation decreased significantly in the 49-72 h age group; 60 Gy dose had no significant effect on egg hatch. Eggs irradiated few hours before hatch (at the blackhead stage), were the most resistant ones; 100 Gy had no significant effect on egg hatch and at 350 Gy dose over 56% of the eggs hatched. When adult emergence was used as a criterion for measuring effectiveness, however, the effect of gamma radiation was very sever. A dose of 60 Gy completely prevented adult emergence and at 100 Gy dose all resulted larvae died before pupation

  2. Anthelmintic resistance in equine nematodes

    Directory of Open Access Journals (Sweden)

    Jacqueline B. Matthews

    2014-12-01

    Full Text Available Anthelmintics have been applied indiscriminately to control horse nematodes for over 40 years. Three broad-spectrum anthelmintic classes are currently registered for nematode control in horses: benzimidazoles (fenbendazole, oxibendazole, tetrahydropyrimidines (pyrantel and macrocyclic lactones (ivermectin, moxidectin. Generally, control strategies have focused on nematode egg suppression regimens that involve the frequent application of anthelmintics to all horses at intervals based on strongyle egg reappearance periods after treatment. The widespread use of such programmes has substantially reduced clinical disease, especially that associated with large strongyle species; however, high treatment frequency has led to considerable selection pressure for anthelmintic resistance, particularly in cyathostomin species. Field studies published over the last decade indicate that benzimidazole resistance is widespread globally in cyathostomins and there are also many reports of resistance to pyrantel in these worms. Cyathostomin resistance to macrocyclic lactone compounds is emerging, principally measured as a reduction in strongyle egg reappearance time observed after treatment. Ivermectin resistance is a further concern in the small intestinal nematode, Parascaris equorum, an important pathogen of foals. These issues indicate that horse nematodes must now be controlled using methods less dependent on anthelmintic use and more reliant on management practices designed to reduce the force of infection in the environment. Such strategies include improved grazing management integrated with targeted anthelmintic administration involving faecal egg count (FEC-directed treatments. The latter require that the supporting diagnostic tests available are robust and practically applicable. Recent research has focused on maximising the value of FEC analysis in horses and on optimizing protocols for anthelmintic efficacy testing. Other studies have sought to develop

  3. [Preservation of live eggs of Schistosoma japonicum].

    Science.gov (United States)

    Lan, Wei-ming; Xie, Shu-ying; Wang, Qin; Jiang, Wei-sheng; Hu, Ren-mei; Ge, Jun; Zeng, Xiao-jun

    2015-10-01

    To observe the preservation time and activity of miracidium hatching from schistosome eggs preserved in different solutions, so as to obtain the optimal preservation conditions and then provide quality control products for field application. The rectum stool of rabbits infected with Schistosoma japonicum was collected and the coarse fecal residue was removed with a series of sample sieves of 80, 100, 160 and 200 meshes respectively, and then the schistosome eggs were concentrated with the sample sieve of 260 meshes. The concentrated eggs were preserved in 0.9% sodium chloride solution, 1.2% sodium chloride solution, phosphate buffered saline solution (PBS, PH 7.2), 1.0% sucrose solution, and Mili-Q water, respectively, and then were conserved in a 4 °C refrigerator and 15 °C constant temperature incubator, respectively. The preserved eggs were hatched in different time (7-day interval) , the vitality and quantity of the miracidia were observed, and the hatching rates were calculated. Under the condition of 4 °C, the hatching rates of eggs dropped to 0 in 1.0% sucrose solution and 1.2% sodium chloride solution at the 49th and 126th day, respectively, and the hatching rates of eggs in the 0.9% sodium chloride solution and PBS solution dropped to 10% at the 112th day, and the activity of miracidium was weakened since 140th. In the Mili-Q water, the hatching rate dropped less than 10% at the 196th day and the activity of miracidia was weakened since the 280th day. Under the condition of 15 °C, the hatching rate of eggs in different solutions gradually dropped to 0 from the 49th day to 105th day. The eggs preserved in Mili-Q water at the temperature of 4 °C can be used as the positive reference for hatching tests within 196 days.

  4. The Effect of Eggshell Thickness on Hatching Traits of Partridges

    Directory of Open Access Journals (Sweden)

    US Yamak

    Full Text Available ABSTRACT Incubation is an important factor in poultry production, particularly in species with relatively low fertility and hatchability rates. This study examined the effect of eggshell thickness on hatching traits of partridges (A. chukar. A total of 462 eggs from intensively reared partridges were separated into three groups according to eggshell thickness, which was measured ultrasonically before incubation. Hatchability, chick weight, and chick length were assessed at the end of the incubation period. Hatching times were recorded during hatching. Embryonic mortalities in unhatched eggs were classified according to mortality stage at the end of incubation. The effect of eggshell thickness on hatchability was found to be insignificant for all groups. Moreover, eggshell thickness had no significant effect on chick weight or length.

  5. Prevalence of drug-resistant gastrointestinal nematodes in an organized sheep farm

    Directory of Open Access Journals (Sweden)

    Ambalathaduvar Meenakshisundaram

    2014-12-01

    Full Text Available Aim: The present study was aimed to determine the resistance against albendazole, fenbendazole, levamisole and closantel in gastrointestinal (GI nematodes of sheep. Introduction: Anthelmintics are used traditionally as an integral part of helminthic control strategies for grazing livestock to prevent production losses from parasitic infections. The continuous and indiscriminate use of the same anthelmintics over years together as the sole means of control are now failing due to the emergence of resistance strains of helminths. Resistance to the commonly used anthelmintics in GI nematodes of sheep has become an increasingly widespread problem throughout the world. Materials and Methods: Fifty-five naturally infected Madras Red lambs of 6-12 months of age were selected and distributed randomly into five treatment groups of 11 animals each. Four groups were treated orally with albendazole (5 mg/kg, fenbendazole (7 mg/kg, levamisole (7.5 mg/kg and closantel (10 mg/kg respectively, whereas the fifth group served as untreated control. Fecal samples were collected per rectum of each lamb just prior to treatment (pre-treatment and on 7, 14, 21 and 28 days post-treatment. The anthelmintic resistance was evaluated by in vivo fecal egg count reduction test (FECRT, post-treatment larval culture and in vitro egg hatch assay. Results: In the FECRT, albendazole reduced the faecal egg count by 86.50%, 84.81%, 85.28% and 84.47% respectively for 4 weeks after treatment. Fecal egg count reduction using fenbendazole was 92.64, 93.04, 90.80 and 90.06% respectively for 4 weeks after treatment. The percent efficacy for levamisole and closantel was more than 95%. The post-treatment larval culture contained only Haemonchus contortus. In the in vitro egg hatch assay, the ED50 value for benzimidazole was 0.299 μg albendazole/ml and levamisole showed an ED50 value of 0.283 μg/ml. Conclusion: Our study confirmed the resistance of H. contortus to benzimidazole in sheep. .

  6. Organic and inorganic selenium in Aseel chicken diets: Effect on hatching traits.

    Science.gov (United States)

    Khan, M T; Mahmud, A; Zahoor, I; Javed, K

    2017-05-01

    A study was conducted to evaluate the effect of dietary selenium (Se) sources (organic and inorganic Se at 0.30 ppm and basal diet at 0 ppm level of supplemented Se) on hatching traits in four varieties of Aseel chicken, Lakha, Mushki, Peshawari, and Mianwali. In total, 84 adult molted hens (50 wk old), 21 from each variety, were randomly assigned to 12 treatment groups in a 3 (Se diets) × 4 (Aseel varieties) factorial arrangement under a randomized complete block design. Each treatment was replicated 7 times with individual hens in each. Settable egg, fertility, hatch of fertile eggs, hatchability, A-grade chick, and embryonic mortality parameters were evaluated. The results indicated that the birds fed an organic Se supplemented diet had greater (P < 0.05) settable eggs, fertility, hatch of fertile eggs, hatchability, and A-grade chicks and reduced embryonic mortality than those fed inorganic or no Se. Among varieties, Mushki had lower (P < 0.05) fertility, hatch of fertile eggs, hatchability, and A-grade chicks than rest of three varieties. Interaction of Se sources and varieties indicated that dietary organic Se supplementation improved (P < 0.05) hatch of fertile eggs in Peshawari and Mianwali, whereas hatchability only in Peshawari variety and reduced embryonic mortality in Mianwali. It was concluded that dietary supplementation of organic Se could be used to improve hatching traits as well as reduce embryonic mortality in native Aseel chicken. © 2016 Poultry Science Association Inc.

  7. Reproductive and life cycle strategies in egg-carrying cyclopoid and free-spawning calanoid copepods

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Sabatini, Marian

    1994-01-01

    Egg-carrying cyclopoid copepods have lower fecundity and feeding rates, and longer egg hatching times, than free-spawning calanoid copepods. Simple demographic considerations suggest that the lower feeding and fecundity of egg-carrying cyclopoids are adaptations to the potentially elevated...... mortality of ovigerous females, while the shorter egg hatching time and higher feeding and fecundity rates found in free-spawning calanoid copepods represent adaptations to the very high mortality rates experienced by suspended eggs....

  8. Hatch, survival and sensory perception

    Science.gov (United States)

    The need to understand the functional biology of nematodes is central both to fundamental science and to practical aspects. Research on the biology of economically important cyst nematodes has frequently had the declared aim of identifying novel control targets based on disruption of the nematode li...

  9. Maternal manipulation of hatching asynchrony limits sibling cannibalism in the predatory mite Phytoseiulus persimilis.

    Science.gov (United States)

    Schausberger, P; Hoffmann, D

    2008-11-01

    1. Sibling cannibalism is a common phenomenon in the animal kingdom but entails a high risk of direct and inclusive fitness loss for the mother and her offspring. Therefore, mechanisms limiting sibling cannibalism are expected to be selected for. One way of maternal manipulation of sibling cannibalism is to influence hatching asynchrony between nearby laid eggs. This has rarely been tested experimentally. 2. We examined the ability of ovipositing females of the cannibalistic predatory mite Phytoseiulus persimilis to influence the occurrence of sibling cannibalism among offspring by manipulating hatching asynchrony of nearby laid eggs. 3. In the first experiment, we assessed the occurrence of sibling cannibalism in relation to the hatching interval (24 h and 48 h) between nearby laid eggs. In the second experiment, we tested whether ovipositing females discriminate sites containing young (24-h old) and old (48-h old) eggs, fresh and old traces (metabolic waste products and possibly pheromones) left by the same female (24 h and 48 h ago), or young eggs plus fresh female traces and old eggs plus old female traces. Both experiments were conducted with and without prey. 4. Without prey, siblings were more likely to cannibalize each other if the hatching interval between nearby laid eggs was short (24 h). Cannibalism occurred less often when senior siblings (protonymphs) experienced a delay in the opportunity to cannibalize junior siblings (larvae). 5. Independent of prey availability, females preferentially added new eggs to sites containing old eggs plus old female traces but did neither distinguish between young and old eggs presented without own traces nor between fresh and old traces presented without eggs. 6. We discuss cue perception and use by P. persimilis females and contrast the outcome of our experiments and theoretical predictions of sibling cannibalism. We conclude that P. persimilis mothers increase hatching asynchrony of nearby laid eggs to prevent

  10. Regulatory interplay between soybean root and soybean cyst nematode during a resistant and susceptible reaction

    Science.gov (United States)

    Background: Plant parasitic nematodes (PPNs) are obligate parasites that feed on the roots of living host plants. Often, these nematodes can lay hundreds of eggs, each capable of surviving in the soil for as long as 12 years. When it comes to wreaking havoc on agricultural yield, few nematodes can c...

  11. THE SHELF LIFE OF BIRD EGGS: TESTING EGG VIABILITY USING A TROPICAL CLIMATE GRADIENT

    Science.gov (United States)

    STEVEN R. BEISSINGER; MARK I. COOK; WAYNE J. ARENDT

    2005-01-01

    Avian parents influence the onset of development, hatching synchrony, and likelihood of brood reduction through the onset of incubation. Studies testing adaptive functions of brood reduction assume that eggs are protected by their shells and waiting for parents to initiate incubation in a manner that creates optimal hatching patterns, but the viability of early laid...

  12. Resting egg production induced by food limitation in the calanoid copepod Acartia tonsa

    DEFF Research Database (Denmark)

    Drillet, Guillaume; Hansen, Benni W.; Kiørboe, Thomas

    2011-01-01

    Three populations of the copepod Acartia tonsa, two from the Baltic Sea and one from the U.S. East Coast, were compared for resting egg production at conditions of saturating and limiting food availability. All three populations produced eggs that hatched within 72 h when incubated at 17°C...... (subitaneous eggs), but the two Baltic populations in addition produced eggs that hatched at a much slower rate, in the course of a month (delayed hatching eggs [DHE]). Such eggs were not produced by the U.S. population. The fraction of DHE increased when food was limiting. Females from a Baltic population...... that were incubated individually all produced subitaneous eggs, but about half the females consistently also produced DHE. Cold storage that mimicked boreal winter conditions synchronized the hatching of DHE after extended storage, indicating that spring hatching of DHE might seed the water column...

  13. Computed tomographic evaluation of dinosar egg shell integrity

    International Nuclear Information System (INIS)

    Jones, J.C.; Greenberg, W.; Ayers, S.

    1998-01-01

    The purpose of this study was to determine whether computed tomography (CT) could be used to identify hatching holes in partially embedded dinosaur eggs. One Faveololithus and two Dendroolithus eggs were examined using a fourth generation CT scanner. The eggs were partially embedded in a fossilized sediment matrix, with the exposed portion of the shell appearing intact. In CT images of all three eggs, the shells appeared hyperdense relative to the matrix. Hatching holes were visible as large gaps in the embedded portion of the shell, with inwardly displaced shell fragments. It was concluded that CT is an effective technique for nondestructively assessing dinosaur egg shell integrity

  14. Anthelmintic Activity of a Herbal Formulation Against Gastrointestinal Nematodes of Sheep

    Directory of Open Access Journals (Sweden)

    Muhammad Arfan Zaman*§, Zafar Iqbal, Muhammad Nisar Khan and Ghulam Muhammad1

    2012-01-01

    Full Text Available This study was carried out to evaluate the anthelmintic activity of a herbal formulation (HF based on aqueous extracts of leaves of Azadirachta indica and Nicotiana tabacum, flowers of Calotropis procera and seeds of Trachyspermum ammi. In vitro, eggs and adult Haemonchus contortus were exposed to different concentrations of HF following the standard procedures of egg hatch test (EHT; 50 to 0.024414 mg ml-1 and adult motility assay (AMA; 200-0.1953125mg ml-1, respectively. The reference drugs used in the study were oxfendazole (0.0056704 to 0.0000027 mg ml-1 and levamisole (1.50 mg ml-1 for EHT and AMA, respectively. In vivo, pre and post-treatment (4 mg, 2 mg and 500 µg kg-1 body weight fecal egg counts were determined following standard fecal egg count reduction test in sheep naturally parasitized with mixed species of gastrointestinal nematodes. In EHT, LC50 values of HF and oxfendazole (reference drug were 275.1 and 0.016 µg ml-1, respectively. In AMA, 100% mortality of H. contortus was observed 6 hr post-exposure to 3.125-200 mg ml-1 concentrations of HF and 2 hr post-exposure to levamisole. In vivo, maximum (96.2% fecal egg count (EPG reduction was recorded in sheep treated with HF @ 4 mg kg-1 body weight; whereas, 89.3% reduction in EPG was recorded in sheep treated with levamisole @ 7.5 mg kg-1 body weight. A graded dose response was noted in all the tests used in the present study to evaluate the anthelmintic activity of HF. Therefore, HF seems to be promising as an anthelmintic for animals. Large scale trials on efficacy and safety, however, are recommended before the HF is considered for commercialization in crude form.

  15. Egg Allergy

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Egg Allergy KidsHealth / For Teens / Egg Allergy What's in ... but it's worth it. What Happens With an Egg Allergy? Eggs aren't bad. But when you' ...

  16. Egg size, egg composition and reproductive success in the Oystercatcher Haematopus ostralegus

    NARCIS (Netherlands)

    Jager, TD; Hulscher, JB; Kersten, M.

    2000-01-01

    We investigated the relationship between egg size and composition and their subsequent effects on hatching and fledging success in Eurasian Oystercatchers Haematopus ostralegus on the island of Schiermonnikoog (53 degrees 30'N, 06 degrees 10'E) in the Dutch Wadden Sea between 1986 and 1990. Egg size

  17. Fish as vectors in the dispersal of Bythotrephes cederstroemi: Diapausing eggs survive passage through the gut

    Science.gov (United States)

    Jarnagin, S.T.; Swan, B.K.; Kerfoot, W.C.

    2000-01-01

    1. Bythotrephes cederstroemi (Crustacea: Onychopoda: Cercopagidae) is an introduced invertebrate predator currently spreading through the Laurentian Great Lakes region of North America. We examined a previously unsuspected way in which B. cederstroemi may be dispersed by fish by their consumption of diapausing eggs. 2. Ninety-four percentage of the mature B. cederstroemi diapausing eggs consumed by fish were egested apparently intact. This proportion is considerably above previous estimates for the ephippial eggs of Daphnia. The hatching success of diapausing eggs was compared among four categories: (a) eggs released naturally by B. cederstroemi (control, 73% hatched (b) eggs released during 'stressful confinement' (46% hatched) (c) eggs dissected from dead females (13% hatched) and (d) eggs recovered from faecal pellets following consumption by fish (viable gut passage experiment, 41% hatched). 3. Samples of small fish and B. cederstroemi were collected simultaneously. Examination of gut contents revealed that fish contained B. cederstroemi diapausing eggs and that B. cederstroemi bearing resting eggs were consumed selectively over those without eggs. Moreover, fish selected B. cederstroemi bearing mature rather than immature diapausing eggs. 4. The fact that diapausing eggs survive gut passage is important for the dispersal of B. cederstroemi. Fish often move between the pelagic and littoral zones of lakes and may thus disperse diapausing eggs widely. Fish may also move between lakes connected by river systems and can be caught and passively dispersed by anglers or piscivorous birds. Our results demonstrate the potential for fish to act as vectors in the spread of B. cederstroemi.

  18. Sperm depletion does not account for undeveloped eggs in blue tits Cyanistes caeruleus

    NARCIS (Netherlands)

    Schut, Elske; Vedder, Oscar; Komdeur, Jan; Magrath, Michael J. L.

    Hatching failure negatively impacts reproductive success in birds. One reason why eggs fail to hatch is that they are not fertilized, which may be because they receive insufficient sperm. In most passerines, copulation declines in frequency or ceases altogether after the laying of the first egg, so

  19. Changes in the air cell volume of artificially incubated ostrich eggs ...

    African Journals Online (AJOL)

    A total of 2160 images of candled, incubated ostrich eggs were digitized to determine the percentage of egg volume occupied by the air cell at different stages of incubation. The air cell on average occupied 2.5% of the volume of fresh eggs. For eggs that hatched successfully, this volume increased to an average of 24.4% ...

  20. Effects of gamma irradiation on the egg stage of the meal moth, Pyralis Farinalis L

    International Nuclear Information System (INIS)

    Gharib, O.H.; Abdelkawy, F.K.

    1993-01-01

    Two days-old eggs of the meal moth, Pyralis Farinalis L. Were exposed to different doses of gamma radiation ranged from 10 to 150 gray. Reduction in egg hatch was highly correlated with the given dose. At control, 83.2% of the eggs hatched and 75.6% of the eggs reached adult stage, whereas egg hatch was reduced to 21.8 , 16.1 and 5.8% after exposures to 100,120 and 150 gray, respectively. No adults emerged after egg irradiation to 150 gray. Gamma irradiation had almost slight effect on larval pupal duration without significant differences. Irradiation of eggs could alter the reproductive ability of the emerged moths. The doses 10, 20 and 40 gray delivered to the egg stage reduced egg production and fertility of the emerging moths. The greatest reduction was obtained when both sexes had been irradiated at 40 gray and paired together. Females were more radiosensitive than males. 2 tab

  1. Effect of a formulation of Bacillus firmus on root-knot nematode Meloidogyne incognita infestation and the growth of tomato plants in the greenhouse and nursery.

    Science.gov (United States)

    Terefe, Metasebia; Tefera, Tadele; Sakhuja, P K

    2009-02-01

    Bacillus firmus, commercial WP formulation (BioNem) was evaluated against the root-knot nematode Meloidogyne incognita in a laboratory, greenhouse and under field conditions on tomato plants. In the laboratory tests, an aqueous suspension of BioNem at 0.5%, 1%, 1.5% and 2% concentration reduced egg hatching from 98% to 100%, 24-days after treatment. Treatment of second-stage juveniles with 2.5% and 3% concentration of BioNem, caused 100% inhibition of mobility, 24 h after treatment. In the green house trials, BioNem applied at 8 g/pot (1200 cc soil) planted with a tomato seedlings reduced gall formation by 91%, final nematode populations by 76% and the number of eggs by 45%. Consequently, plant height and biomass was increased by 71% and 50%, respectively, compared to the untreated control, 50-days after treatment application. Application of BioNem at 16 g/pot was phytotoxic to plants. In the field trails, BioNem applied at 200 and 400 kg ha(-1) was effective in reducing the number of galls (75-84%), and increased shoot height (29-31%) and weight (20-24%) over the untreated control, 45-days after treatment. Our results indicate that B. firmus is a promising microorganism for the biological control of M. incognita in tomato pots.

  2. An evolutionary insight into the hatching strategies of pipefish and seahorse embryos.

    Science.gov (United States)

    Kawaguchi, Mari; Nakano, Yuko; Kawahara-Miki, Ryouka; Inokuchi, Mayu; Yorifuji, Makiko; Okubo, Ryohei; Nagasawa, Tatsuki; Hiroi, Junya; Kono, Tomohiro; Kaneko, Toyoji

    2016-03-01

    Syngnathiform fishes carry their eggs in a brood structure found in males. The brood structure differs from species to species: seahorses carry eggs within enclosed brood pouch, messmate pipefish carry eggs in the semi-brood pouch, and alligator pipefish carry eggs in the egg compartment on abdomen. These egg protection strategies were established during syngnathiform evolution. In the present study, we compared the hatching mode of protected embryos of three species. Electron microscopic observations revealed that alligator pipefish and messmate pipefish egg envelopes were thicker than those of seahorses, suggesting that the seahorse produces a weaker envelope. Furthermore, molecular genetic analysis revealed that these two pipefishes possessed the egg envelope-digesting enzymes, high choriolytic enzyme (HCE), and low choriolytic enzyme (LCE), as do many euteleosts. In seahorses, however, only HCE gene expression was detected. When searching the entire seahorse genome by high-throughput DNA sequencing, we did not find a functional LCE gene and only a trace of the LCE gene exon was found, confirming that the seahorse LCE gene was pseudogenized during evolution. Finally, we estimated the size and number of hatching gland cells expressing hatching enzyme genes by whole-mount in situ hybridization. The seahorse cells were the smallest of the three species, while they had the greatest number. These results suggest that the isolation of eggs from the external environment by paternal bearing might bring the egg envelope thin, and then, the hatching enzyme genes became pseudogenized. J. Exp. Zool. (Mol. Dev. Evol.) 9999B:XX-XX, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Mechanisms and Characterization of Trichoderma longibrachiatum T6 in Suppressing Nematodes (Heterodera avenae in Wheat

    Directory of Open Access Journals (Sweden)

    Shuwu Zhang

    2017-09-01

    Full Text Available Heterodera avenae is an important soil-borne pathogen that affects field crops worldwide. Chemical nematicides can be used to control the nematode, but they bring toxicity to the environment and human. Trichoderma longibrachiatum has been shown to have the ability to control H. avenae cysts, but detailed microscopic observations and bioassays are lacking. In this study, we used microscopic observations and bioassays to study the effect of T. longibrachiatum T6 (TL6 on the eggs and second stage juveniles (J2s of H. avenae, and investigate the role of TL6 in inducing the resistance to H. avenae in wheat seedling at physiological and biochemical levels. Microscopic observations recorded that TL6 parasitized on the H. avenae eggs, germinated, and produced a large number of hyphae on the eggs surface at the initial stage, thereafter, the eggs were completely surrounded by dense mycelia and the contents of eggs were lysed at the late stage. Meanwhile, the conidia suspension of TL6 parasitized on the surface of J2s, produced a large number of hyphae that penetrated the cuticle and caused deformation of the nematodes. TL6 at the concentration of 1.5 × 107 conidia ml−1 had the highest rates of parasitism on eggs and J2s, reflected by the highest hatching-inhibition of eggs and the mortality of J2s. In the greenhouse experiments, wheat seedlings treated with TL6 at 1.5 × 107 conidia ml−1 had reduced H. avenae infection, and increased plant growth significantly compared to the control. The cysts and juveniles in soil were reduced by 89.8 and 92.7%, the juveniles and females in roots were reduced by 88.3 and 91.3%, whereas the activity of chitinase and β-1, 3-glucanase, total flavonoids and lignin contents in wheat roots were increased significantly at different stage after inoculation with the eggs and TL6 conidia in comparison to the control. Maximum activity of chitinase and β-1, 3-glucanase were recorded at the 20th and 15th Days after

  4. Does hatching failure breed infidelity?

    OpenAIRE

    Malika Ihle; Bart Kempenaers; Wolfgang Forstmeier

    2013-01-01

    In socially monogamous species, the reasons for female infidelity are still controversial. It has been suggested that females could seek extra-pair copulations as an insurance against hatching failure caused by male infertility or incompatibility. In species where couples breed repeatedly, females could use previous hatching success as a cue to assess their partner’s infertility (or incompatibility). Hence, it has been predicted that females should increase their infidelity after experiencing...

  5. Unexpected variation in neuroanatomy among diverse nematode species

    Directory of Open Access Journals (Sweden)

    Ziduan eHan

    2016-01-01

    Full Text Available Nematodes are considered excellent models for understanding fundamental aspects of neuron function. However, nematodes are less frequently used as models for examining the evolution of nervous systems. While the habitats and behaviors of nematodes are diverse, the neuroanatomy of nematodes is often considered highly conserved. A small number of nematode species greatly influences our understanding of nematode neurobiology. The free-living species Caenorhabditis elegans and, to a lesser extent, the mammalian gastrointestinal parasite Ascaris suum are, historically, the primary sources of knowledge regarding nematode neurobiology. Despite differences in size and habitat, C. elegans and Ascaris suum share a surprisingly similar neuroanatomy. Here, we examined species across several clades in the phylum Nematoda and show that there is a surprising degree of neuroanatomical variation both within and among nematode clades when compared to C. elegans and Ascaris. We found variation in the numbers of neurons in the ventral nerve cord and dye-filling pattern of sensory neurons. For example, we found that Pristionchus pacificus, a bacterial feeding species used for comparative developmental research, had 20% fewer ventral cord neurons compared to C. elegans. Steinernema carpocapse, an insect-parasitic nematode capable of jumping behavior, had 40% more ventral cord neurons than C. elegans. Interestingly, the non-jumping congeneric nematode, S. glaseri showed an identical number of ventral cord neurons as S. carpocapsae. There was also variability in the timing of neurodevelopment of the ventral cord with two of five species that hatch as second-stage juveniles showing delayed neurodevelopment. We also found unexpected variation in the dye-filling of sensory neurons among examined species. Again, sensory neuron dye-filling pattern did not strictly correlate with phylogeny. Our results demonstrate that variation in nematode neuroanatomy is more prevalent

  6. Glassfrog embryos hatch early after parental desertion

    OpenAIRE

    Delia, Jesse R. J.; Ramírez-Bautista, Aurelio; Summers, Kyle

    2014-01-01

    Both parental care and hatching plasticity can improve embryo survival. Research has found that parents can alter hatching time owing to a direct effect of care on embryogenesis or via forms of care that cue the hatching process. Because parental care alters conditions critical for offspring development, hatching plasticity could allow embryos to exploit variation in parental behaviour. However, this interaction of parental care and hatching plasticity remains largely unexplored. We tested th...

  7. Intraspecific variation in egg size and egg composition in birds: effects on offspring fitness.

    Science.gov (United States)

    Williams, T D

    1994-02-01

    1. There is little unequivocal evidence to date in support of a positive relationship between egg size and offspring fitness in birds. Although 40 studies (of 34 species) have considered the effect of variation in egg size on chick growth and/or survival up to fledgling only 12 studies have controlled for other characters potentially correlated both with egg size and offspring fitness. Of these only two have reported a significant residual effect of egg size on chick growth (in the roseate tern and European blackbird) and three a residual effect on chick survival (all in seabirds: common tern, lesser black-backed gull and kittiwake). 2. More consistent evidence exists, though from fewer studies, for a positive relationship between egg size and offspring fitness early in the chick-rearing period; chick growth and chick survival being dependent on egg size in 8 of 10 studies and 4 of 5 studies respectively. It is suggested that the most important effect of variation in egg size might be in determining the probability of offspring survival in the first few days after hatching. 3. Egg size explains on average 66% of the variation in chick mass at hatching (n = 35 studies) but only 30% of the variation in chick body size (n = 18). When effects of hatching body size are controlled for chick mass remains significantly correlated with egg size, though the reverse is not true. This supports the hypothesis that large eggs give rise to heavier chicks at hatching, i.e., chicks with more nutrient (yolk) reserves, rather than structurally larger chicks. 4. Egg composition increased isometrically with increasing egg size in about half the studies so far reported (n equals approximately 20). However, in seabirds, and some passerines, larger eggs contain disproportionately more albumen, whilst in some waterfowl percentage yolk content increases with increasing egg size. Changes in albumen content largely reflect variation in the water content of eggs, but changes in yolk content

  8. Application of the FluEgg model to predict transport of Asian carp eggs in the Saint Joseph River (Great Lakes tributary)

    Science.gov (United States)

    Garcia, Tatiana; Murphy, Elizabeth A.; Jackson, P. Ryan; Garcia, Marcelo H.

    2015-01-01

    The Fluvial Egg Drift Simulator (FluEgg) is a three-dimensional Lagrangian model that simulates the movement and development of Asian carp eggs until hatching based on the physical characteristics of the flow field and the physical and biological characteristics of the eggs. This tool provides information concerning egg development and spawning habitat suitability including: egg plume location, egg vertical and travel time distribution, and egg-hatching risk. A case study of the simulation of Asian carp eggs in the Lower Saint Joseph River, a tributary of Lake Michigan, is presented. The river hydrodynamic input for FluEgg was generated in two ways — using hydroacoustic data and using HEC-RAS model data. The HEC-RAS model hydrodynamic input data were used to simulate 52 scenarios covering a broad range of flows and water temperatures with the eggs at risk of hatching ranging from 0 to 93% depending on river conditions. FluEgg simulations depict the highest percentage of eggs at risk of hatching occurs at the lowest discharge and at peak water temperatures. Analysis of these scenarios illustrates how the interactive relation among river length, hydrodynamics, and water temperature influence egg transport and hatching risk. An improved version of FluEgg, which more realistically simulates dispersion and egg development, is presented. Also presented is a graphical user interface that facilitates the use of FluEgg and provides a set of post-processing analysis tools to support management decision-making regarding the prevention and control of Asian carp reproduction in rivers with or without Asian carp populations.

  9. The Hatch-Smolensk exchange

    International Nuclear Information System (INIS)

    Sproles, A.

    1993-01-01

    During summer 1992, the World Association of Nuclear Operators (WANO) sponsored an exchange visit between Georgia Power Company's Edwin I. Hatch nuclear plant, a two-unit boiling water reactor site, and the Smolensk atomic energy station, a three-unit RBMK (graphite-moderated and light-water-cooled) plant located 350 km west of Moscow, in Desnogorsk, Russia. The Plant Hatch team included Glenn Goode, manager of engineering support; Curtis Coggin, manager of training and emergency preparedness; Wayne Kirkley, manager of health physics and chemistry; John Lewis, manager of operations; Ray Baker, coordinator of nuclear fuels and contracts; and Bruce McLeod, manager of nuclear maintenance support. Also traveling with the team was Jerald Towgood, of WANO's Atlanta Centre. The Hatch team visited the Smolensk plant during the week of July 27, 1992

  10. Modeling winter moth Operophtera brumata egg phenology: nonlinear effects of temperature and developmental stage on developmental rate

    NARCIS (Netherlands)

    Salis, Lucia; Lof, Marjolein; Van Asch, M.; Visser, Marcel E.

    2016-01-01

    Understanding the relationship between an insect's developmental rate and temperature is crucial to forecast insect phenology under climate change. In the winter moth Operophtera brumata timing of egg-hatching has severe fitness consequences on growth and reproduction as egg-hatching has to match

  11. Efficacy of free and nanoencapsulated Eucalyptus citriodora essential oils on sheep gastrointestinal nematodes and toxicity for mice.

    Science.gov (United States)

    Ribeiro, J C; Ribeiro, W L C; Camurça-Vasconcelos, A L F; Macedo, I T F; Santos, J M L; Paula, H C B; Araújo Filho, J V; Magalhães, R D; Bevilaqua, C M L

    2014-08-29

    Herbal medicines with anthelmintic effects are alternatives for the sustainable control and prevention of disease caused by gastrointestinal parasites. The nanoencapsulation of essential oils has been proposed to enhance the absorption of their constituents and improve their efficacy. The present study aimed to evaluate the efficacy of free and nanoencapsulated Eucalyptus citriodora essential oil (EcEO) on the control of gastrointestinal nematodes of small ruminants in vitro and in vivo. Chitosan was used as a matrix for the formulation of a nanoemulsion. Chromatographic and physico-chemical analyses of EcEO were performed. Egg hatch (EHT) and larval development (LDT) tests were conducted to evaluate the effectiveness of nanoencapsulated and free EcEO on the eggs and larvae of Haemonchus contortus. Acute toxicity of free and nanoencapsulated EcEO was evaluated using mice. Finally, nanoencapsulated EcEO efficacy on the control of gastrointestinal nematodes was calculated by fecal egg count reduction test (FECRT) treating 30 sheep naturally infected with 250 mg/kg of free and nanoencapsulated EcEO. In vitro tests were analyzed by an analysis of variance (ANOVA) followed by comparison with the Tukey test. The efficacy of FECRT was calculated by the BootStreet program through arithmetic average, using the formula 100 (1-XT/XC). To compare the differences between epg, the data were transformed to log(x+1) and subjected to an ANOVA to compare the significant differences between groups by Tukey's. The level of significance was P<0.05. The free (4 mg/ml concentration) and nanoencapsulated (2mg/ml concentration) EcEO inhibited larvae hatching by 97.2% and 92.8%, respectively. Free and nanoencapsulated EcEO at 8 mg/ml inhibited larval development by 99.8% and 98.1%, respectively. In the acute toxicity test, the LD10 and LD50 of free EcEO was 1999 and 2653 mg/kg, respectively, while the LD10 and LD50 of nanoencapsulated EcEO was 1121 and 1681 mg/kg, respectively

  12. Relationship between Egg weight, Hatch weight and Subsequent ...

    African Journals Online (AJOL)

    sola

    plumage, they are known for their adaptation superiority in terms of their ... tribe and they are best preserved because of the cultural lifestyle of the Fulani ... A. A. Toye, Department of Animal Production, University of Ilorin, Kwara state, Nigeria.

  13. Morphology and identification of fly eggs: application in forensic entomology.

    Science.gov (United States)

    Sanit, S; Sribanditmongkol, P; Sukontason, K L; Moophayak, K; Klong-Klaew, T; Yasanga, T; Sukontason, K

    2013-06-01

    Fly eggs found in corpses can be used as entomological evidence in forensic investigation. This study aims to investigate the morphology of forensically important fly eggs. Eggs of Chrysomya rufifacies, Chrysomya megacephala, Chrysomya pinguis, Chrysomya nigripes, Hypopygiopsis tumrasvini, Lucilia cuprina, Lucilia porphyrina and Musca domestica were examined using 1% potassium permanganate solution for 1 min. Morphometric analysis revealed that the mean length of Hy. tumrasvini (1.63 mm) and C. pinguis (1.65 mm) eggs was the longest, followed by that of L. porphyrina (1.45 mm), C. rufifacies (1.34 mm). The egg length, width of median area and darkness staining of hatching pleats were distinctive features. Four categories of median area were proposed, based on width; (1) distinctly wide (Megaselia scalaris, Synthesiomyia nudiseta); (2) wide (C. nigripes, M. domestica); (3) slightly widening (Hy. tumrasvini, L. cuprina, L. porphyrina); and (4) narrow (C. rufifacies, C. albiceps, C. megacephala, C. pinguis). Four species were examined using SEM, i.e., C. megacephala, C. pinguis, Hy. tumrasvini and L. porphyrina. The eggs of C. megacephala demonstrated swollen hatching pleats. Inside, the hexagon of the chorion appeared as a sponging bumpy feature. The egg of C. pinguis was similar to C. megacephala, except for the sponging bumpy feature on the outer surface of the hatching pleats. Regarding Hy. tumrasvini and L. porphyrina, their island structure was apparent at the inner surface of the upright hatching pleats. The key for identifying these eggs together with other reported species in Thailand has been updated.

  14. A Big Bang or small bangs? Effects of biotic environment on hatching

    Directory of Open Access Journals (Sweden)

    Marina MANCA

    2008-08-01

    Full Text Available The beginning and end of diapause are two important transition points in cladoceran life history. The influence of environmental variables on the dynamics of these processes still deserves attention, especially as concerns the role of biotic factors. In this paper we focus on emergence from diapause, testing (1 whether ephippia of Daphnia obtusa Kurz can assess the presence in the water of typical planktivorous fish or ostracods, and (2 whether such an assessment results in changes in hatching strategy. Total number of hatchlings from D. obtusa ephippial eggs did not differ between the control and the treatments in which the presence of fish or ostracods could be detected (ANOVA, P = 0.884. However, hatching dynamics were different: most of the eggs hatched synchronously at day 4 (83.3% of the total hatchlings number in the control, while only a low proportion of eggs hatched on day 4 in the fish (38.3%, and ostracod treatments (24.0% of the total. Mean hatching time was longer, and variability larger, in the treatments than in the control; differences resulted statistically significant (ANOVA, P = 0.005. With respect to the control, representing a simple microcosm controlled by abiotic variables only, the treatments may be regarded as relatively complex environments, in which Daphnia is also exposed to biotic cues. Under these more complex conditions, the same number of hatchlings is obtained through different hatching dynamics. In the treatments, the first hatchlings appeared later and the hatching rate was more variable than in the control. These observations confirm previously observed patterns from laboratory experiments which tested the effect of competition and fluctuating environmental conditions (light:dark, temperature regimes on D. obtusa reproductive and demographic parameters. They are also in agreement with recently obtained evidence concerning the importance of biotic cues for hatching of ephippial eggs. Overall, the evidence

  15. A synthetic peptide shows retro- and anterograde neuronal transport before disrupting the chemosensation of plant-pathogenic nematodes.

    Directory of Open Access Journals (Sweden)

    Dong Wang

    2011-03-01

    Full Text Available Cyst nematodes are a group of plant pathogens each with a defined host range that cause major losses to crops including potato, soybean and sugar beet. The infective mobile stage hatches from dormant eggs and moves a short distance through the soil to plant roots, which it then invades. A novel strategy for control has recently been proposed in which the plant is able to secrete a peptide which disorientates the infective stage and prevents invasion of the pathogen. This study provides indirect evidence to support the mechanism by which one such peptide disrupts chemosensory function in nematodes. The peptide is a disulphide-constrained 7-mer with the amino acid sequence CTTMHPRLC that binds to nicotinic acetylcholine receptors. A fluorescently tagged version of this peptide with both epifluorescent and confocal microscopy was used to demonstrate that retrograde transport occurs from an aqueous environment along bare-ending primary cilia of chemoreceptive sensilla. The peptide is transported to the cell bodies of these neurons and on to a limited number of other neurons to which they connect. It appears to be localised in both neuronal processes and organelles adjacent to nuclei of some neurons suggesting it could be transported through the Golgi apparatus. The peptide takes 2.5 h to reach the neuronal cell bodies. Comparative studies established that similar but less abundant uptake occurs for Caenorhabditis elegans along its well studied dye-filling chemoreceptive neurons. Incubation in peptide solution or root-exudate from transgenic plants that secrete the peptide disrupted normal orientation of infective cyst nematodes to host root diffusate. The peptide probably undergoes transport along the dye-filling non-cholinergic chemoreceptive neurons to their synapses where it is taken up by the interneurons to which they connect. Coordinated responses to chemoreception are disrupted when the sub-set of cholinergic interneurons secrete the peptide

  16. A synthetic peptide shows retro- and anterograde neuronal transport before disrupting the chemosensation of plant-pathogenic nematodes.

    Science.gov (United States)

    Wang, Dong; Jones, Laura M; Urwin, Peter E; Atkinson, Howard J

    2011-03-07

    Cyst nematodes are a group of plant pathogens each with a defined host range that cause major losses to crops including potato, soybean and sugar beet. The infective mobile stage hatches from dormant eggs and moves a short distance through the soil to plant roots, which it then invades. A novel strategy for control has recently been proposed in which the plant is able to secrete a peptide which disorientates the infective stage and prevents invasion of the pathogen. This study provides indirect evidence to support the mechanism by which one such peptide disrupts chemosensory function in nematodes. The peptide is a disulphide-constrained 7-mer with the amino acid sequence CTTMHPRLC that binds to nicotinic acetylcholine receptors. A fluorescently tagged version of this peptide with both epifluorescent and confocal microscopy was used to demonstrate that retrograde transport occurs from an aqueous environment along bare-ending primary cilia of chemoreceptive sensilla. The peptide is transported to the cell bodies of these neurons and on to a limited number of other neurons to which they connect. It appears to be localised in both neuronal processes and organelles adjacent to nuclei of some neurons suggesting it could be transported through the Golgi apparatus. The peptide takes 2.5 h to reach the neuronal cell bodies. Comparative studies established that similar but less abundant uptake occurs for Caenorhabditis elegans along its well studied dye-filling chemoreceptive neurons. Incubation in peptide solution or root-exudate from transgenic plants that secrete the peptide disrupted normal orientation of infective cyst nematodes to host root diffusate. The peptide probably undergoes transport along the dye-filling non-cholinergic chemoreceptive neurons to their synapses where it is taken up by the interneurons to which they connect. Coordinated responses to chemoreception are disrupted when the sub-set of cholinergic interneurons secrete the peptide at synapses that

  17. Temperature-induced plasticity in egg size and resistance of eggs to temperature stress in a soil arthropod

    NARCIS (Netherlands)

    Liefting, M.; Weerenbeck, M.; Dooremalen, van C.; Ellers, J.

    2010-01-01

    Keywords:acclimation;cold shock;development rate;egg hatching;heat shock;phenotypic plasticity;Orchesella cincta;oviposition temperature Summary 1. Temperature is considered one of the most important mediators of phenotypic plasticity in ectotherms, resulting in predictable changes in egg size.

  18. Oxygen requirement of separated hybrid catfish eggs

    Science.gov (United States)

    Channel catfish egg masses require hatchery water with over 7.8 ppm dissolved oxygen at 80° F (95% air saturation) to maintain maximum oxygen consumption as they near hatching. This concentration is called the critical oxygen requirement by scientists but for the purpose of this article we will call...

  19. Multiple Modes of Nematode Control by Volatiles of Pseudomonas putida 1A00316 from Antarctic Soil against Meloidogyne incognita

    Directory of Open Access Journals (Sweden)

    Yile Zhai

    2018-02-01

    Full Text Available Pseudomonas putida 1A00316 isolated from Antarctic soil showed nematicidal potential for biological control of Meloidogyne incognita; however, little was known about whether strain 1A00316 could produce volatile organic compounds (VOCs, and if they had potential for use in biological control against M. incognita. In this study, VOCs produced by a culture filtrate of P. putida 1A00316 were evaluated by in vitro experiments in three-compartment Petri dishes and 96-well culture plates. Our results showed that M. incognita juveniles gradually reduced their movement within 24–48 h of incubation with mortality ranging from 6.49 to 86.19%, and mostly stopped action after 72 h. Moreover, egg hatching in culture filtrates of strain 1A00316 was much reduced compared to that in sterile distilled water or culture medium. Volatiles from P. putida 1A00316 analysis carried out by solid-phase micro-extraction gas chromatography–mass spectrometry (SPME-GC/MS included dimethyl-disulfide, 1-undecene, 2-nonanone, 2-octanone, (Z-hexen-1-ol acetate, 2-undecanone, and 1-(ethenyloxy-octadecane. Of these, dimethyl-disulfide, 2-nonanone, 2-octanone, (Z-hexen-1-ol acetate, and 2-undecanone had strong nematicidal activity against M. incognita J2 larvae by direct-contact in 96-well culture plates, and only 2-undecanone acted as a fumigant. In addition, the seven VOCs inhibited egg hatching of M. incognita both by direct-contact and by fumigation. All of the seven VOCs repelled M. incognita J2 juveniles in 2% water agar Petri plates. These results show that VOCs from strain 1A00316 act on different stages in the development of M. incognita via nematicidal, fumigant, and repellent activities and have potential for development as agents with multiple modes of control of root-knot nematodes.

  20. Egg size matching by an intraspecific brood parasite

    Science.gov (United States)

    Lemons, Patrick R.; Sedinger, James S.

    2011-01-01

    Avian brood parasitism provides an ideal system with which to understand animal recognition and its affect on fitness. This phenomenon of laying eggs in the nests of other individuals has classically been framed from the perspective of interspecific brood parasitism and host recognition of parasitic eggs. Few examples exist of strategies adopted by intraspecific brood parasites to maximize success of parasitic eggs. Intraspecific brood parasitism within precocial birds can be a risky strategy in that hatch synchrony is essential to reproductive success. Given that egg size is positively correlated with incubation time, parasitic birds would benefit by recognizing and selecting hosts with a similar egg size. Intraspecific brood parasitism is an alternative reproductive strategy in black brant (Branta bernicla nigricans), a colonial nesting goose with precocial young. Based on a randomization test, parasitic eggs in this study differed less in size from eggs in their host's nests than did random eggs placed in random nests. Parasitic eggs were remarkably similar in size to hosts’ eggs, differing by nests differed by nearly 8%. The precision with which parasitic brant match the egg size of hosts in our study supports our hypothesis that brant match egg size of hosts, thereby maximizing hatching success of their parasitic eggs.

  1. Spawning Characteristics and Artificial Hatching of Female Mottled Skate, Beringraja pulchra in the West Coast of Korea.

    Science.gov (United States)

    Kang, Hee-Woong; Jo, Yeong-Rok; Kang, Duk-Yong; Jeong, Gyeong-Suk; Jo, Hyun-Su

    2013-09-01

    The gonadsomatic index (GSI) of mottled skate was the highest in April, GSI and HSI showed a reverse phase for its reproductive cycle. The fish had one pair of egg capsules, having 1 to 7 fertilized eggs, and spawned all the year round. When surveying the reproductive characteristics of females over 63 ㎝ in disc width, we found the spawning peak was between April to June, and the appearance ratio of egg capsules was the highest in May (32.1%). The eggs were hatched at 8°C, 13°C, 18°C, water temperature (12.8 to 24.2°C), and the best hatching temperature was 18°C. The number of fish hatched was 4 to 5 fish/egg capsules, and the hatching rate was 100%. The sex ratios of hatching larvae were 45.5% female and 54.5% male. Therefore this study will provide fundamental data and information for artificial reproduction of the mottled skate.

  2. Periodical low eggshell temperatures during incubation and post hatch dietary arginine supplementation

    NARCIS (Netherlands)

    Afsarian, O.; Shahir, M.H.; Akhlaghi, A.; Lotfolahian, H.; Hoseini, A.; Lourens, A.

    2016-01-01

    An experiment was conducted to evaluate the effects of a periodically low eggshell temperature exposure during incubation and dietary supplementation of arginine on performance, ascites incidence, and cold tolerance acquisition in broilers. A total of 2,400 hatching eggs were randomly assigned to

  3. Development of Atlantic salmon (Salmo salar) eggs and alevins under varied temperature regimes

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, R H; Spinney, H C.E.; Sreedharan, A

    1977-01-01

    Atlantic salmon (Salmo salar) eggs and alevins were raised under conditions where the temperature was systematically varied either at fertilization, at the eyed egg stage, or at hatching. Mortality was more than 20% in eggs started immediately after fertilization at constant incubation temperatures <4/sup 0/C as compared with 5% or less at temperatures >4/sup 0/C. Alevins that eyed at 8/sup 0/C and higher were progressively smaller the higher the temperature. The optimum temperature from fertilization to eye pigmentation was near 6/sup 0/C. Eyed eggs reared at lower temperatures until hatching were larger than those hatched at higher temperatures. This size differential was maintained until the yolk was completely absorbed at all posthatching temperatures investigated. Sudden decreases in temperature at the eyed egg and hatching stages induced severe edema of the alevin yolk sac, resulting in slower growth and increased mortality.

  4. Mobile Incubation in Waved Albatross (Phoebastria irrorata: Associated Hatching Failure and Artificial Mitigation

    Directory of Open Access Journals (Sweden)

    Jill A. Awkerman

    2005-12-01

    Full Text Available Waved albatrosses often relocate their eggs during incubation by placing the egg between the tarsi and shuffling forward. This behavior frequently results in eggs becoming lodged between rocks, accounting for at least 10%, and perhaps as much as 80%, of breeding failures. Because albatross populations worldwide are currently threatened, artificial means of augmenting reproductive success may be necessary to mitigate losses caused by anthropogenic effects. We characterize the frequency and extent of egg movement; test several hypotheses related to microhabitat, timing, and incubation location to explain the behavior; and investigate the utility of repositioning lodged eggs in a location in which breeding birds might resume incubation. Egg rescue increased both the likelihood of continued incubation as well as the hatching rate in our experiment, and provides an efficient, low-cost management option for this species.

  5. The effect of low changes in radiation dose on the hatching data of rainbow trout

    International Nuclear Information System (INIS)

    Buehringer, H.; Kellermann, H.J.

    1993-01-01

    Radiation hormesis hypothesis refers to the occurrence of a biphasic dose-respond relationship in which higher doses cause an inhibitory effect and lower doses cause a stimulatory effect. By extrapolation of this thesis there could be suggested a radiation damage effect below normal background radiation doses. Rainbow trout eggs, which are very radiation sensitive, were fertilized and incubated in environments with abient radiation (Hamburg), increased doses of radiation and decreased level of radiation doses (ASSE II). Hatching data (incubation time, hatching time, hatching success, number and kind of malformations, length of larvae) were examined for a hormesis effect. Only in hatching success a statistically significant effect of radiation dose was noticeable. (orig.) [de

  6. Survey of Hatching Spines of Bee Larvae Including Those of Apis mellifera (Hymenoptera: Apoidea).

    Science.gov (United States)

    Rozen, Jerome G; Shepard Smith, Corey; Cane, James H

    2017-07-01

    This article explores the occurrence of hatching spines among bee taxa and how these structures enable a larva on hatching to extricate itself from the egg chorion. These spines, arranged in a linear sequence along the sides of the first instar just dorsal to the spiracles, have been observed and recorded in certain groups of solitary and cleptoparasitic bee taxa. After eclosion, the first instar remains loosely covered by the egg chorion. The fact that this form of eclosion has been detected in five families (Table 1 identifies four of the families. The fifth family is the Andrenidae for which the presence of hatching spines in the Oxaeinae will soon be announced.) of bees invites speculation as to whether it is a fundamental characteristic of bees, or at least of solitary and some cleptoparasitic bees. The wide occurrence of these spines has prompted the authors to explore and discover their presence in the highly eusocial Apis mellifera L. Hatching spines were indeed discovered on first instar A. mellifera. The honey bee hatching process appears to differ in that the spines are displayed somewhat differently though still along the sides of the body, and the chorion, instead of splitting along the sides of the elongate egg, seems to quickly disintegrate from the emerging first instar in association with the nearly simultaneous removal of the serosa that covers and separates the first instar from the chorion. Unexpected observations of spherical bodies of various sizes perhaps containing dissolving enzymes being discharged from spiracular openings during hatching may shed future light on the process of how A. mellifera effects chorion removal during eclosion. Whereas hatching spines occur among many groups of bees, they appear to be entirely absent in the Nomadinae and parasitic Apinae, an indication of a different eclosion process. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  7. Metal stress in zooplankton diapause production: post-hatching response.

    Science.gov (United States)

    Aránguiz-Acuña, Adriana; Pérez-Portilla, Pablo

    2017-04-01

    Aquatic organisms commonly respond to harsh conditions by forming diapausing stages, which enable populations to survive adverse periods forming egg banks. Production of diapausing eggs is frequently observed in monogonont rotifers, previously changing from asexual to partial sexual reproduction (mixis). In despite that zooplankton are frequently used in ecotoxicological assessment because of their sensitivity to various toxicants and their important role in the ecosystems, toxicity evaluations often consider the directly exposed population produced by parthenogenetic reproduction, exclusively. We assessed experimentally effects of exposure to metals on mixis delay and fitness of hatchlings of the rotifer Brachionus plicatilis obtained from a brackish water lagoon with high metal content, especially copper. We show that sub-lethal concentrations of copper affected traits related to sexual reproduction and diapausing egg production in the rotifer. Copper addition did not delay the start of mixis, suggesting that rapid initiation of mixis is promoted in risky environments, according to the hypothesis of mixis as an escape strategy. Higher investment in mixis was obtained when individuals were exposed to metal. Addition of copper negatively affected the hatching success of diapausing eggs and performance of hatchlings. Nevertheless, these effects were greater for individuals formed in non-metal conditions, suggesting an adaptive advantage of populations from natural sediments exposed to copper. These results highlight the ecological and evolutionary consequences of the presence of metals in freshwater environments by modulating diapause adaptive efficacy and the selective process in egg banks.

  8. Hatching asynchrony aggravates inbreeding depression in a songbird (Serinus canaria): an inbreeding-environment interaction.

    Science.gov (United States)

    de Boer, Raïssa A; Eens, Marcel; Fransen, Erik; Müller, Wendt

    2015-04-01

    Understanding how the intensity of inbreeding depression is influenced by stressful environmental conditions is an important area of enquiry in various fields of biology. In birds, environmental stress during early development is often related to hatching asynchrony; differences in age, and thus size, impose a gradient in conditions ranging from benign (first hatched chick) to harsh (last hatched chick). Here, we compared the effect of hatching order on growth rate in inbred (parents are full siblings) and outbred (parents are unrelated) canary chicks (Serinus canaria). We found that inbreeding depression was more severe under more stressful conditions, being most evident in later hatched chicks. Thus, consideration of inbreeding-environment interactions is of vital importance for our understanding of the biological significance of inbreeding depression and hatching asynchrony. The latter is particularly relevant given that hatching asynchrony is a widespread phenomenon, occurring in many bird species. The exact causes of the observed inbreeding-environment interaction are as yet unknown, but may be related to a decrease in maternal investment in egg contents with laying position (i.e. prehatching environment), or to performance of the chicks during sibling competition and/or their resilience to food shortage (i.e. posthatching environment). © 2015 The Author(s).

  9. Balancing Eggs

    Science.gov (United States)

    Mills, Allan

    2014-01-01

    Theory predicts that an egg-shaped body should rest in stable equilibrium when on its side, balance vertically in metastable equilibrium on its broad end and be completely unstable on its narrow end. A homogeneous solid egg made from wood, clay or plastic behaves in this way, but a real egg will not stand on either end. It is shown that this…

  10. Effect of Paecilomyces lilacinus, Trichoderma harzianum and Trichoderma virens fungal extracts on the hatchability of Ancylostoma eggs.

    Science.gov (United States)

    Hofstätter, Bianca Delgado Menezes; Oliveira da Silva Fonseca, Anelise; de Souza Maia Filho, Fernando; de Souza Silveira, Julia; Persici, Beatriz Maroneze; Pötter, Luciana; Silveira, Andressa; Antoniolli, Zaida Inês; Brayer Pereira, Daniela Isabel

    Ancylostoma species have demanded attention due to their zoonotic potential. The use of anthelmintics is the usual method to prevent environmental contamination by Ancylostoma eggs and larvae. Nematophagous fungi have been widely used in their biological control due to the fungus ability to capture and digest free nematode forms. The aim of this study was to evaluate the effect of four different fungal extracts of Paecilomyces lilacinus (n=2), Trichoderma harzianum (n=1) and Trichoderma virens (n=1) isolates on the hatchability of Ancylostoma eggs. Fungal extracts consisted of fungal broth culture supernatant without filtration (crude extract) and filtered broth (filtered extract), macerated mycelium (crude macerate), and macerated mycelium submitted to filtration (filtered macerate). The Ancylostoma eggs were obtained from the feces of naturally infected dogs. In vitro assays were performed in five replicates and consisted of four treatments and one control group. The activity of the fungal extracts of each evaluated fungus differed (p<0.05) from those of the control group, showing significant ovicidal activity. The hatching of the eggs suffered reduction percentages of 68.43% and 47.05% with P. lilacinus, and 56.43% with T. harzianum, when crude macerate extract was used. The reduction with the macerate extract of T. virens was slightly lower (52.25%) than that for the filtered macerate (53.64%). The results showed that all extracts were effective in reducing the hatchability of Ancylostoma eggs. The ovicidal effect observed is likely to have been caused by the action of hydrolytic enzymes secreted by the fungi. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

  11. Learning hatching for pen-and-ink illustration of surfaces

    KAUST Repository

    Kalogerakis, Evangelos; Nowrouzezahrai, Derek; Breslav, Simon; Hertzmann, Aaron

    2012-01-01

    This article presents an algorithm for learning hatching styles from line drawings. An artist draws a single hatching illustration of a 3D object. Her strokes are analyzed to extract the following per-pixel properties: hatching level (hatching

  12. Mother-Offspring Relations: Prey Quality and Maternal Size Affect Egg Size of an Acariphagous Lady Beetle in Culture

    Directory of Open Access Journals (Sweden)

    Eric W. Riddick

    2012-01-01

    Full Text Available We investigated mother-offspring relations in a lady beetle Stethorus punctillum Weise that utilizes spider mites as prey. Our objectives were to determine if (1 prey quality affects egg size, (2 maternal size correlates with egg size, and (3 egg size affects hatching success. We fed predators spider mites Tetranychus urticae Koch from lima bean Phaseolus lunatus L. foliage in the laboratory. Mothers of unknown body size offered high rather than low quality spider mites since birth produced larger eggs. Mothers of known body size offered only high quality spider mites, produced eggs of variable size, but mean egg size correlated positively with hind femur length. Mothers laid their eggs singly, rather than in batches, and eggs were large relative to femur size. Egg size did not affect hatch success; mean hatch rate exceeded 95% regardless of egg size. In conclusion, the quality of prey consumed by S. punctillum mothers while in the larval stage can affect their size as adults and, consequently, the size of their eggs. The behavior of laying eggs singly, the positive relationship between maternal size and mean egg size, and the high rate of egg hatch suggest that S. punctillum mothers invest heavily in offspring.

  13. Mother and offspring fitness in an insect with maternal care: phenotypic trade-offs between egg number, egg mass and egg care

    Science.gov (United States)

    2014-01-01

    Background Oviparous females have three main options to increase their reproductive success: investing into egg number, egg mass and/or egg care. Although allocating resources to either of these three components is known to shape offspring number and size, potential trade-offs among them may have key impacts on maternal and offspring fitness. Here, we tested the occurrence of phenotypic trade-offs between egg number, egg mass and maternal expenditure on egg care in the European earwig, Forficula auricularia, an insect with pre- and post-hatching forms of maternal care. In particular, we used a series of laboratory observations and experiments to investigate whether these three components non-additively influenced offspring weight and number at hatching, and whether they were associated with potential costs to females in terms of future reproduction. Results We found negative associations between egg number and mass as well as between egg number and maternal expenditure on egg care. However, these trade-offs could only be detected after statistically correcting for female weight at egg laying. Hatchling number was not determined by single or additive effects among the three life-history traits, but instead by pairwise interactions among them. In particular, offspring number was positively associated with the number of eggs only in clutches receiving high maternal care or consisting of heavy eggs, and negatively associated with mean egg mass in clutches receiving low care. In contrast, offspring weight was positively associated with egg mass only. Finally, maternal expenditure on egg care reduced their future reproduction, but this effect was only detected when mothers were experimentally isolated from their offspring at egg hatching. Conclusions Overall, our study reveals simultaneous trade-offs between the number, mass and care of eggs. It also demonstrates that these factors interact in their impact on offspring production, and that maternal expenditure on egg

  14. Resistance to benzimidazoles and levamisole in nematode parasites of sheep in Nyandarua district of Kenya

    DEFF Research Database (Denmark)

    Maingi, N.; Bjørn, H.; Gichohi, V.M.

    1998-01-01

    The occurrence of anthelmintic resistance on 25 sheep farms in the Nyandarua District of Kenya was investigated, using the faecal egg count reduction test (FECRT), the egg hatch assay (EHA) and a larval development assay (LDA). In the FECRT, resistance to both benzimidazoles (BZs) and levamisole...

  15. Avian Egg and Egg Coat.

    Science.gov (United States)

    Okumura, Hiroki

    2017-01-01

    An ovulated egg of vertebrates is surrounded by unique extracellular matrix, the egg coat or zona pellucida, playing important roles in fertilization and early development. The vertebrate egg coat is composed of two to six zona pellucida (ZP) glycoproteins that are characterized by the evolutionarily conserved ZP-domain module and classified into six subfamilies based on phylogenetic analyses. Interestingly, investigations of biochemical and functional features of the ZP glycoproteins show that the roles of each ZP-glycoprotein family member in the egg-coat formation and the egg-sperm interactions seemingly vary across vertebrates. This might be one reason why comprehensive understandings of the molecular basis of either architecture or physiological functions of egg coat still remain elusive despite more than 3 decades of intensive investigations. In this chapter, an overview of avian egg focusing on the oogenesis are provided in the first section, and unique features of avian egg coat, i.e., perivitelline layer, including the morphology, biogenesis pathway, and physiological functions are discussed mainly on chicken and quail in terms of the characteristics of ZP glycoproteins in the following sections. In addition, these features of avian egg coat are compared to mammalian zona pellucida, from the viewpoint that the structural and functional varieties of ZP glycoproteins might be associated with the evolutionary adaptation to their reproductive strategies. By comparing the egg coat of birds and mammals whose reproductive strategies are largely different, new insights into the molecular mechanisms of vertebrate egg-sperm interactions might be provided.

  16. Factors affecting hatch success of hawksbill sea turtles on Long Island, Antigua, West Indies.

    Directory of Open Access Journals (Sweden)

    Mark Allan Ditmer

    Full Text Available Current understanding of the factors influencing hawksbill sea turtle (Eretmochelys imbricata hatch success is disparate and based on relatively short-term studies or limited sample sizes. Because global populations of hawksbills are heavily depleted, evaluating the parameters that impact hatch success is important to their conservation and recovery. Here, we use data collected by the Jumby Bay Hawksbill Project (JBHP to investigate hatch success. The JBHP implements saturation tagging protocols to study a hawksbill rookery in Antigua, West Indies. Habitat data, which reflect the varied nesting beaches, are collected at egg deposition, and nest contents are exhumed and categorized post-emergence. We analyzed hatch success using mixed-model analyses with explanatory and predictive datasets. We incorporated a random effect for turtle identity and evaluated environmental, temporal and individual-based reproductive variables. Hatch success averaged 78.6% (SD: 21.2% during the study period. Highly supported models included multiple covariates, including distance to vegetation, deposition date, individual intra-seasonal nest number, clutch size, organic content, and sand grain size. Nests located in open sand were predicted to produce 10.4 more viable hatchlings per clutch than nests located >1.5 m into vegetation. For an individual first nesting in early July, the fourth nest of the season yielded 13.2 more viable hatchlings than the initial clutch. Generalized beach section and inter-annual variation were also supported in our explanatory dataset, suggesting that gaps remain in our understanding of hatch success. Our findings illustrate that evaluating hatch success is a complex process, involving multiple environmental and individual variables. Although distance to vegetation and hatch success were inversely related, vegetation is an important component of hawksbill nesting habitat, and a more complete assessment of the impacts of specific

  17. Sensitivity of root-knot nematodes to gamma irradiation, salinity and plant growth regulator, cycocel

    Energy Technology Data Exchange (ETDEWEB)

    Sweelam, M E [Econ. Entomology Dept., Fac. Agric. Menoufia University Shebin El-Kom, (Egypt)

    1995-10-01

    The experiment was carried out at the experimental station of the faculty of agriculture, Menoufia Univ. To determine the sensitivity of root-knot nematode, Meloidogyne Javanica infecting tomato plants exposed to different doses of gamma irradiation 0,20,40,60,80 Gy, salinity levels 0. 1000, 2000, 4000 ppm and the plant growth regulator cycocel 0,200 ppm. Treated seeds were planted clay pots and salinity levels and cycocel concentrations were applied. Fresh weights and nematode populations were computed 3 months after application. Results indicated that 20 Gy, 1000 ppm salinity and cycocel gave the highest fresh weight of shoots and roots. The developmental stages and egg-laying females of nematode decreased by the increasing of irradiation dose and salinity levels. Root-knot galls decreased with 40 and 60 Gy, while significant increase was observed with 0 and 80 Gy, salinity levels decreased root galls. Cycocel decreased nematode population, egg-lying females and root-knot galls.

  18. Sensitivity of root-knot nematodes to gamma irradiation, salinity and plant growth regulator, cycocel

    International Nuclear Information System (INIS)

    Sweelam, M.E.

    1995-01-01

    The experiment was carried out at the experimental station of the faculty of agriculture, Menoufia Univ. To determine the sensitivity of root-knot nematode, Meloidogyne Javanica infecting tomato plants exposed to different doses of gamma irradiation 0,20,40,60,80 Gy, salinity levels 0. 1000, 2000, 4000 ppm and the plant growth regulator cycocel 0,200 ppm. Treated seeds were planted clay pots and salinity levels and cycocel concentrations were applied. Fresh weights and nematode populations were computed 3 months after application. Results indicated that 20 Gy, 1000 ppm salinity and cycocel gave the highest fresh weight of shoots and roots. The developmental stages and egg-laying females of nematode decreased by the increasing of irradiation dose and salinity levels. Root-knot galls decreased with 40 and 60 Gy, while significant increase was observed with 0 and 80 Gy, salinity levels decreased root galls. Cycocel decreased nematode population, egg-lying females and root-knot galls

  19. Chick Development and Asynchroneous Hatching in the Zebra Finch (Taeniopygia guttata castanotis).

    Science.gov (United States)

    Ikebuchi, Maki; Okanoya, Kazuo; Hasegawa, Toshikazu; Bischof, Hans-Joachim

    2017-10-01

    The mode of hatching in birds has important impacts on both parents and chicks, including the costs and risks of breeding for parents, and sibling competition in a clutch. Birds with multiple eggs in a single clutch often begin incubating when most eggs are laid, thereby reducing time of incubation, nursing burden, and sibling competition. In some songbirds and some other species, however, incubation starts immediately after the first egg is laid, and the chicks thus hatch asynchronously. This may result in differences in parental care and in sibling competition based on body size differences among older and younger chicks, which in turn might produce asynchronous development among siblings favoring the first hatchling, and further affect the development and fitness of the chicks after fledging. To determine whether such processes in fact occur in the zebra finch, we observed chick development in 18 clutches of zebra finches. We found that there were effects of asynchronous hatching, but these were smaller than expected and mostly not significant. Our observations suggest that the amount of care given to each chick may be equated with such factors as a camouflage effect of the down feathers, and that the low illumination within the nest also complicates the determination of the hatching order by the parents.

  20. The application of superweak bioluminescence on freshness degree of chicken egg

    International Nuclear Information System (INIS)

    Zhao Hongxia; Li Guochen; Li Qiangzheng; Li Juan

    2007-01-01

    The luminescence of chicken egg in storage is studied by a detection system of superweak bioluminescence. The results show that egg has the strongest vigour on the third day after it is laid, subsequently the luminescence presents decay with oscillation. These eggs, which have been stored for 3 days, are most suitable for hatching. Different eggs have different luminescence intensities depending on the vigour of the egg. The stronger the vigour of the egg is, the more intensive the luminescence is. Superweak bioluminescence as a comprehensive index of biology and biochemistry response can be used for inspecting the freshness degree of the egg, and the test is nondestructive and sensitive

  1. Chemical surface disinfection of eggs of Baltic cod, Gadus morhua L

    DEFF Research Database (Denmark)

    Overton, J L; Bruun, Morten Sichlau; Dalsgaard, Inger

    2010-01-01

    The effect of two disinfectants on eggs and larvae of Baltic cod, Gadus morhua, was investigated. The eggs were disinfected for 10 min using various concentrations of either glutaraldehyde (100, 200, 400, 600 and 800 mg L−1) or iodophor (10, 50, 100 and 150 mg L−1), 1–4-days post......-fertilization. Bactericidal effect of disinfection, survival to hatching, hatching success and larval abnormalities were assessed. Larval survival was recorded at 5-, 10- and 15-days post-hatch (dph). Although Baltic cod eggs have an unusually thin chorion, they could tolerate surface disinfection. A reduction in bacterial...... growth was observed with increased concentrations of disinfectant (3.0 × 107–1.6 × 101 CFU mL−1). Abnormalities in newly hatched larvae were not related to disinfection. Survival of the yolk sac larvae was significantly better for eggs treated with 400 mg L−1 glutaraldehyde for 10 min at 10 and 15 dph...

  2. Microbial infection affects egg viability and incubation behavior in a tropical passerine.

    Science.gov (United States)

    Mark I. Cook; Steven R. Beissinger; Gary A. Toranzos; Roberto A. Arendt Rodriguez

    2004-01-01

    Many avian species initiate incubation before clutch completion, which causes eggs to hatch asynchronously. This influences brood competitive dynamics and often results in nestling mortality. The prevailing hypotheses contend that parents incubate early because asynchronous hatching provides fitness benefits to parents or surviving offspring. An alternative idea is...

  3. Effects on the Growth and Survival of Eggs and Embryos of the California Grunion (Leuresthes tenuis) Exposed to Trace Levels of Tributyltin.

    Science.gov (United States)

    1985-05-01

    postfertilization exposure of grunion eggs to low doses of TBT has no effect on hatch success or notochord length at time of hatch. 2. No = exposure of...grunion eggs and sperm during fertilization and sub- sequent low-level dose incubation has no effect on fertilization, hatch suc- cess, or notochord ...clean glass vials for stor- -.- - age. Ten randomly selected larvae from each replicate were also measured for notochord length and examined for

  4. Nematode-Trapping Fungi.

    Science.gov (United States)

    Jiang, Xiangzhi; Xiang, Meichun; Liu, Xingzhong

    2017-01-01

    Nematode-trapping fungi are a unique and intriguing group of carnivorous microorganisms that can trap and digest nematodes by means of specialized trapping structures. They can develop diverse trapping devices, such as adhesive hyphae, adhesive knobs, adhesive networks, constricting rings, and nonconstricting rings. Nematode-trapping fungi have been found in all regions of the world, from the tropics to Antarctica, from terrestrial to aquatic ecosystems. They play an important ecological role in regulating nematode dynamics in soil. Molecular phylogenetic studies have shown that the majority of nematode-trapping fungi belong to a monophyletic group in the order Orbiliales (Ascomycota). Nematode-trapping fungi serve as an excellent model system for understanding fungal evolution and interaction between fungi and nematodes. With the development of molecular techniques and genome sequencing, their evolutionary origins and divergence, and the mechanisms underlying fungus-nematode interactions have been well studied. In recent decades, an increasing concern about the environmental hazards of using chemical nematicides has led to the application of these biological control agents as a rapidly developing component of crop protection.

  5. Efeito do tempo de jejum pós-eclosão, valores energéticos e inclusão do ovo desidratado em dietas pré-iniciais e iniciais de pintos de corte Effect of post-starvation hatching time, energy levels and addition of dried egg in pre-initial and initial diets for broiler chicks

    Directory of Open Access Journals (Sweden)

    Elisanie Neiva Magalhães Teixeira

    2009-02-01

    Full Text Available Dois experimentos foram realizados para determinar o valor nutricional do ovo desidratado (OD, o efeito do tempo de jejum pós-eclosão (TJPe e a inclusão do ovo desidratado em rações para frangos de corte. No primeiro experimento, 120 pintos de corte machos, linhagem Ross-308, foram alojados em delineamento inteiramente casualizado, com três tratamentos e cinco repetições de oito aves. As coletas de excretas foram realizadas no período de 24 a 29 dias de idade, pela manhã e à tarde. No segundo experimento, um lote misto de 810 pintos da linhagem Cobb-500, com peso vivo inicial 33,41 ± 0,53, foi alojado em boxes de 1,0 × 1,5 m. O delineamento experimental utilizado foi o inteiramente casualizado com 9 tratamentos e 6 repetições de 15 aves, em esquema fatorial 3 × 3, com três níveis de ovo desdratado (0, 2 e 4% e três tempos de jejum pós-eclosão (28, 40 e 52 horas, correpondentes a 0, 12 e 24 horas de jejum pós-alojamento, respectivamente. O ovo desidratado apresentou 51,54% de PB e 4.278 kcal EMAn. Na fase de 1 a 7 dias, o peso vivo, o ganho de peso e o consumo de ração entre as aves submetidas a jejum de 40 e 52 horas foram inferiores aos daquelas alimentadas mais cedo (às 28 horas do tempo de jejum pós-eclosão, enquanto as aves submetidas a 52 horas de jejum pós-eclosão (24 horas de jejum pós alojamento apresentaram os piores resultados. O nível de 4% de ovo desidratado na ração pré-inicial melhorou o peso vivo no segundo e terceiro dia de idade dos pintinhos. No período de 1 a 21 dias, o ovo desidratado pode ser utlizado na alimentação de frangos, pois não prejudica o desempenho das aves.Two experiments were carried out to determine the nutritional value of the dried egg (DEGG, and the effect of the post-starvation hatching time (PSHT and the inclusion of dried egg powder in the diet of broiler chicks. In experiment 1, 120 male Ross-308 broiler chicks were housed according to a completely randomized design

  6. Effects of a combined hatching and brooding system on hatchability, chick weight, and mortality in broilers.

    Science.gov (United States)

    van de Ven, L J F; van Wagenberg, A V; Groot Koerkamp, P W G; Kemp, B; van den Brand, H

    2009-11-01

    Chicks hatch over a time window of approximately 36 to 48 h and are removed from the hatchers only when the majority of the chicks has hatched. Consequently, chicks are exposed to prolonged posthatch holding periods and delays in feed and water access, leading to dehydration and impaired posthatch performance. It is questionable whether the physiological requirements of the hatchlings can be met with current hatching systems. An alternative system that may better match the requirements of the hatchlings is a system that combines the hatching and brooding phase, so that feed and water can be provided immediately after hatch. Such a system, named Patio, was developed in the Netherlands and tested from 2006 to 2008, to evaluate effects on hatchability and early performance of broilers. This paper describes the Patio system and the results from these tests. A total of 21 broiler production trials (780,686 eggs) in the Patio system were evaluated at 3 locations and compared with control hatches of eggs of the same parental flock in the hatchery. Hatchability in the Patio was on average 1.45, 1.83, and 1.86% higher at location 1, 2, and 3, respectively. However, in the calculation of the hatchability in the Patio, possible second grade chicks were included, whereas these were excluded in the calculation of hatchability in the hatchery. Additionally, in the hatchery, the hatching process was interrupted earlier than in the Patio, meaning that possible late hatching chicks remained in the flock in the Patio, but not in the hatchery. In 3 trials, the Patio chicks were 11.6 to 16.3% heavier at d 0, when the hatchery chicks were placed in the broiler house. Mean cumulative 7-d mortality was only assessed in the Patio and was 1.27, 1.09, and 1.43% at location 1, 2, and 3, respectively. The Patio system appears to function as an alternative to current hatching and brooding systems. Further studies are required to determine to what extent the higher hatchability is due to second

  7. Worldwide Spacecraft Crew Hatch History

    Science.gov (United States)

    Johnson, Gary

    2009-01-01

    The JSC Flight Safety Office has developed this compilation of historical information on spacecraft crew hatches to assist the Safety Tech Authority in the evaluation and analysis of worldwide spacecraft crew hatch design and performance. The document is prepared by SAIC s Gary Johnson, former NASA JSC S&MA Associate Director for Technical. Mr. Johnson s previous experience brings expert knowledge to assess the relevancy of data presented. He has experience with six (6) of the NASA spacecraft programs that are covered in this document: Apollo; Skylab; Apollo Soyuz Test Project (ASTP), Space Shuttle, ISS and the Shuttle/Mir Program. Mr. Johnson is also intimately familiar with the JSC Design and Procedures Standard, JPR 8080.5, having been one of its original developers. The observations and findings are presented first by country and organized within each country section by program in chronological order of emergence. A host of reference sources used to augment the personal observations and comments of the author are named within the text and/or listed in the reference section of this document. Careful attention to the selection and inclusion of photos, drawings and diagrams is used to give visual association and clarity to the topic areas examined.

  8. Physiological and DNA fingerprinting of the bacterial community of Meloidogyne fallax egg masses

    NARCIS (Netherlands)

    Papert, A; Kok, CJ; van Elsas, JD

    2004-01-01

    Bacterial communities associated with the plant-parasitic nematode Meloidogyne fallax egg masses were compared with those present in the rhizoplane. Two agricultural soils with different nematode population dynamics were used in a glasshouse study, with either potato or tomato as host plant for the

  9. Physiological and DNA fingerprinting of the bacterial community of Meloidogyne fallax egg masses

    NARCIS (Netherlands)

    Papert, A; Kok, CJ; van Elsas, JD

    Bacterial communities associated with the plant-parasitic nematode Meloidogyne fallax egg masses were compared with those present in the rhizoplane. Two agricultural soils with different nematode population dynamics were used in a glasshouse study, with either potato or tomato as host plant for the

  10. Evaluation of sodium carbonate peroxyhydrate as a potential catfish egg disinfectant.

    Science.gov (United States)

    Small, Brian C

    2009-06-01

    Two experiments were conducted to evaluate the efficacy of sodium carbonate peroxyhydrate (SCP) in improving the hatching success of channel catfish Ictalurus punctatus when used as a prophylactic chemotherapeutant during egg incubation. In the first experiment, the efficacy of SCP was evaluated in 379-L aluminum incubation troughs similar to those used in commercial hatcheries. Egg masses treated daily with 254 mg of SCP/L of water had significantly higher mean hatching success than untreated controls, and a pathogen-inhibiting effect was also evident (i.e., no gross infection was observed on the treated egg masses). In the second experiment, the hatching success of egg masses treated daily with 254 mg/L was compared with that of egg masses treated daily with hydrogen peroxide (70 mg/L). The effects of both treatments on the pH, dissolved oxygen, and hydrogen peroxide concentrations in the trough were also examined. Both SCP and hydrogen peroxide significantly improved hatching success. Unlike in the treatment with hydrogen peroxide, water pH increased during the treatment with SCP; however, no negative effects on hatching success were observed. The results of this research suggest that SCP acts similarly to hydrogen peroxide in improving channel catfish hatching success and warrants further research to determine whether it could be a practical and effective alternative for managing catfish egg infections in commercial hatcheries.

  11. Effect of in ovo injection of corticotropin-releasing hormone on the timing of hatching in broiler chickens.

    Science.gov (United States)

    Watanabe, Yugo; Grommen, Sylvia V H; De Groef, Bert

    2017-09-01

    In chicken embryos, intravenous injection of corticotropin-releasing hormone (CRH) causes the release of both corticosteroids and thyroid hormones. These hormones initiate and enhance the hatching process, raising the possibility that CRH treatment of the late chicken embryo could accelerate hatching and/or decrease the spread of hatching. We performed a series of exploratory tests to investigate whether in ovo delivery methods of CRH other than intravenous injection that are more practical in a commercial setting, affect hatching time in broilers. Corticotropin-releasing hormone was injected into the air cell, albumen, or amniotic fluid of broiler breeder eggs, in the last week of embryonic development. Average incubation duration was significantly decreased by 22 h when 2 μg of CRH was injected into the air cell on embryonic day 18 (E18) of Cobb eggs. Acceleration of hatching (but only by 8 h) was also seen for Ross chicks when CRH was injected daily into the albumen between E10 and E18. However, repeats of both experiments did not show consistent effects of CRH on hatching time; in most experiments performed, CRH did not affect hatching time. We speculate that the effectiveness of CRH uptake via these delivery methods and/or the duration and magnitude of the thyroxine and corticosterone response to CRH is not sufficient to have a substantial effect on hatching time. We therefore conclude that in ovo CRH treatment does not seem a feasible option as a practical tool to increase hatchery productivity or to investigate the effects of CRH agonists and antagonists on hatching. © 2017 Poultry Science Association Inc.

  12. Heavier chicks at hatch improves marketing body weight by enhancing skeletal muscle growth.

    Science.gov (United States)

    Sklan, D; Heifetz, S; Halevy, O

    2003-11-01

    This study examined some of the factors connected with the greater marketing weight observed in chicks hatching with higher BW. Examination of chicks hatching from maternal flocks of different ages indicated that BW at hatch increased quadratically and yolk sac weight linearly with age, whereas components of the gastrointestinal tract showed no significant trend. Growth of pectoralis muscles and gastrointestinal tract were compared in chicks hatching at the same weight from maternal flocks of 28 and 64 wk of age and in chicks from the same maternal flock (44 wk old) hatching at different weights. The results indicated that no differences were found among chicks hatching with the same weight from maternal flocks of different ages. In contrast, in chicks from the same maternal flock hatching at different weights the gastrointestinal tract tended to compose a smaller proportion of BW in large chicks, and its growth was not correlated with performance. Liver proportions were greater in heavier chicks. Pectoralis growth and satellite cell numbers and activity were greater in heavier chicks through 5 d posthatch, and pectoralis muscles were heavier at marketing. Examination of some of the growth factors involved suggested that in heavier chicks satellite cells underwent higher proliferation and earlier differentiation during their critical period of activity in the immediate posthatch days. To determine when these differences in activity were established, examination of 15-d embryonic myoblast activity indicated that at this stage activity was already greater in the heavier eggs. This finding suggests that programming of muscle growth may be completed in late embryonic stages. This study suggests that enhanced satellite cell activity is involved in increased growth of chicks hatching with higher BW.

  13. Phylogency and Evolution of Nematodes

    NARCIS (Netherlands)

    Bert, W.; Karssen, G.; Helder, J.

    2011-01-01

    Many plant-parasitic nematodes including members of the genera Meloidogyne (root-knot nematodes), Heterodera and Globodera (cyst nematodes) and Pratylenchus (lesion nematodes) are studied as they cause major damage to crops such as potato, tomato, soybean and sugar beet. Both for fundamental reasons

  14. Feeding activity in Groups of Newly Hatched Broiler Chicks: Effects of strain and hatching time

    DEFF Research Database (Denmark)

    Nielsen, Birte Lindstrøm; Juul-Madsen, Helle Risdahl; Steenfeldt, Sanna

    2010-01-01

    The feeding activity of 2 strains of broiler chickens was investigated during their first week of life in relation to their hatching time. Fast (Ross 308) and slow-growing (LB) strains were allocated to 1 of 3 (early, middle, or late hatch) single-strain groups of 80 to 100 as-hatched birds in 4...

  15. Perinatal broiler physiology between hatching and chick collection in 2 hatching systems

    NARCIS (Netherlands)

    Ven, van de L.J.F.; Wagenberg, van A.V.; Decuypere, E.; Kemp, B.; Brand, van den H.

    2013-01-01

    Little is known about physiological responses of early- versus late-hatching chicks to early posthatch conditions in broiler practice. We investigated effects of hatching time on perinatal broiler physiology in 2 hatching systems, differing in conditions: a conventional hatcher, where chicks are

  16. Radiation disinfection or disinfestation of nematodes, aphids, mites, thrips, and other pests on food plant materials: evaluation for effectiveness and product quality

    Energy Technology Data Exchange (ETDEWEB)

    Moy, J H; Chinnasri, B; Sipes, B S; Schmitt, D P; Hamasaki, R T; Mersino, E F; Yamakawa, R M [Hawaii Institute of Tropical Agriculture and Human Resources, University of Hawaii at Manoa, Honolulu, HI (United States)

    1999-05-01

    Many fresh herbs, ornamental plants, and several varieties of taro grown in Hawaii are infested with various pests such as aphids, mites, thrips, and nematodes. Finding an efficacious quarantine treatment for these commodities is difficult because most cannot tolerate heat or cold, and a suitable chemical treatment is lacking. Irradiation could be a feasible, practical alternative. Quality of these irradiated materials should be studied to help determine if irradiation is a suitable quarantine treatment. Of the ten fresh herbs irradiated with up to 0.70 kGy, five (rosemary, thyme, oregano, parsley, chives) are very tolerant, and show no difference from the controls after two to three weeks at 7 deg. C. Red ginger and four cultivars of heliconia, very attractive ornamental plants, can be irradiated at 0.75 and 0.50 kGy, respectively, and have a vase life of 10 days or more at 21 deg. C. Leafminer in bean plants cannot emerge when irradiated at 0.15 kGy. The nematode, Meloidogyne javanica, which infects taro and ginger, is prevalent in Hawaii. To cause mortality in second stage juveniles (J2), a gamma-radiation dose higher than 4.0 kGy is necessary. Suppression of hatching of egg masses requires doses of 2.0 kGy and above. Galling of tomato plants inoculated with J2 and egg masses decreases when J2 and egg masses were irradiated at 3.25 kGy and above. Heating J2 at 43 deg. C for 10 min before inoculating them into the plants effectively reduces root galling. Synergism was not found between heat treatment (49 deg. C for 10 or 20 min) and irradiation with up to 0.015 kGy, the dose above which sprouting of ginger rhizomes and taro cormels is inhibited. The results suggest that irradiation is promising as a quarantine treatment for selected fresh herbs and ornamental plants, but not for control of nematodes in root crops. (author) 10 refs, 3 tabs

  17. Radiation disinfection or disinfestation of nematodes, aphids, mites, thrips, and other pests on food plant materials: evaluation for effectiveness and product quality

    International Nuclear Information System (INIS)

    Moy, J.H.; Chinnasri, B.; Sipes, B.S.; Schmitt, D.P.; Hamasaki, R.T.; Mersino, E.F.; Yamakawa, R.M.

    1999-01-01

    Many fresh herbs, ornamental plants, and several varieties of taro grown in Hawaii are infested with various pests such as aphids, mites, thrips, and nematodes. Finding an efficacious quarantine treatment for these commodities is difficult because most cannot tolerate heat or cold, and a suitable chemical treatment is lacking. Irradiation could be a feasible, practical alternative. Quality of these irradiated materials should be studied to help determine if irradiation is a suitable quarantine treatment. Of the ten fresh herbs irradiated with up to 0.70 kGy, five (rosemary, thyme, oregano, parsley, chives) are very tolerant, and show no difference from the controls after two to three weeks at 7 deg. C. Red ginger and four cultivars of heliconia, very attractive ornamental plants, can be irradiated at 0.75 and 0.50 kGy, respectively, and have a vase life of 10 days or more at 21 deg. C. Leafminer in bean plants cannot emerge when irradiated at 0.15 kGy. The nematode, Meloidogyne javanica, which infects taro and ginger, is prevalent in Hawaii. To cause mortality in second stage juveniles (J2), a gamma-radiation dose higher than 4.0 kGy is necessary. Suppression of hatching of egg masses requires doses of 2.0 kGy and above. Galling of tomato plants inoculated with J2 and egg masses decreases when J2 and egg masses were irradiated at 3.25 kGy and above. Heating J2 at 43 deg. C for 10 min before inoculating them into the plants effectively reduces root galling. Synergism was not found between heat treatment (49 deg. C for 10 or 20 min) and irradiation with up to 0.015 kGy, the dose above which sprouting of ginger rhizomes and taro cormels is inhibited. The results suggest that irradiation is promising as a quarantine treatment for selected fresh herbs and ornamental plants, but not for control of nematodes in root crops. (author)

  18. Seasonal variations in larval biomass and biochemical composition of brown shrimp, Crangon crangon (Decapoda, Caridea), at hatching

    Science.gov (United States)

    Urzúa, Ángel; Anger, Klaus

    2013-06-01

    The "brown shrimp", Crangon crangon (Linnaeus 1758), is a benthic key species in the North Sea ecosystem, supporting an intense commercial fishery. Its reproductive pattern is characterized by a continuous spawning season from mid-winter to early autumn. During this extended period, C. crangon shows significant seasonal variations in egg size and embryonic biomass, which may influence larval quality at hatching. In the present study, we quantified seasonal changes in dry weight (W) and chemical composition (CHN, protein and lipid) of newly hatched larvae of C. crangon. Our data revealed significant variations, with maximum biomass values at the beginning of the hatching season (February-March), a decrease throughout spring (April-May) and a minimum in summer (June-September). While all absolute values of biomass and biochemical constituents per larva showed highly significant differences between months ( P larvae" hatching from larger "winter eggs" showed higher initial values of biomass compared to "summer larvae" originating from smaller "summer eggs". This indicates carry-over effects persisting from the embryonic to the larval phase. Since "winter larvae" are more likely exposed to poor nutritional conditions, intraspecific variability in larval biomass at hatching is interpreted as part of an adaptive reproductive strategy compensating for strong seasonality in plankton production and transitory periods of larval food limitation.

  19. Adaptive hatching hypotheses do not explain asynchronous ...

    African Journals Online (AJOL)

    At the core of the suite of adaptive hatching hypotheses advanced to explain asynchronous hatching in birds is the assumption that if food is not limited then all the hatchlings will develop normally to adulthood. In this study Brown-headed Parrot Poicephalus cryptoxanthus chicks were hand fed and weighed on a daily basis.

  20. Viabilidade de ovos de nematódeos gastrintestinais de bovinos após passagem em biodigestor anaeróbio Inactivation of trichostrongylid nematode eggs by anaerobic digestion of cattle slurry

    Directory of Open Access Journals (Sweden)

    John Furlong

    1996-08-01

    Full Text Available Em um estudo realizado no Centro Nacional de Pesquisa de Gado de Leite (CNPGL da EMBRAPA, em Coronel Pacheco, Zona da Mata de Minas Gerais, utilizou-se um biodigestor modelo indiano, com o objetivo de estimar o efeito inativante da fermentação anaeróbica em ovos de nematódeos gastrintestinais de bovinos. Amostras de fezes foram contidas em cilindros metálicos telados com malha de 22m e submersas no biodigestor por períodos de 7, 14, 21, 28, 42 e 56 dias. Os resultados do número de larvas recuperadas foi comparado com amostras padrão, submetidas a condições ótimas para o desenvolvimento dos ovos. Somente foram conseguidos níveis de motivação de ovos maiores que 80%, em amostras retidas por períodos superiores a 30 dias. Os efluentes de biodigestores podem veicular contaminação para culturas e pastagens fornecidas verdes, especialmente os oriundos de biodigestores mesofílicos operados com períodos de retenção menores que 30 dias.An experiment was carried out at the National Dairy Cattle Research Center, of EMBRAPA (Brazilian Agricultural Research Organization, in Coronel Pacheco, Zona da Mata Region of Minas Gerais State. To estimate the rate of inactivity of gastro-intestinal worm eggs submitted to anaerobic conditions on a biodigester (Indian model, fecal samples were contained in metallic cylinders with 22m openings and submerged in the anaerobic digester for 7. 14. 21. 28 and 56 days. The number of larvae extracted from culture of the feces after digester passage was compared with cultures mantained in optimal conditions. Levels of inactivation of eggs were greater than 80% only in samples retained for more than 30 days in the biodigester. Effluents of anaerobic digester are potential contaminators of gastro-intestinal worm eggs to crops and fodders, specially in mesophilic digesters, with small chambers, in which the retention period is less than 30 days.

  1. Egg Allergy

    Science.gov (United States)

    ... with eggs. Prevention is the name of the game with food allergies, so it's important for kids ... protein from other foods. Some good ones are meat, poultry, fish, and legumes (beans and peanuts). If ...

  2. Relationship between production, nematodes and "redness" in strawberries

    Directory of Open Access Journals (Sweden)

    Paula Nogueira Curi

    2016-08-01

    Full Text Available ABSTRACT: In recent years "redness" has increasingly appeared in strawberry plants with leaves taking on a reddish color. No causal agent has been associated with plants. Since strawberries presented problems due to the incidence of nematodes, the purpose of this study was to look at the relationship between production, resistance to the Meloidogyne hapla nematode and the "redness" symptom in strawberry cultivars. Two experiments were performed, both with the 'Camino Real', 'Festival', 'Oso Grande', 'Albion' and 'Camarosa' cultivars. The first experiment was performed in the field, where the following were evaluated: strawberry production, fruit quality, macro and micronutrient contents in fruit and leaves, percentage of plant survival, incidence of nematodes, quantity of eggs in the roots and juveniles in the soil, and the incidence of Botrytis cinerea . In the second experiment, the strawberries were transplanted into pots and filled with pinus bark-based commercial substrate. Half the pots were inocculated with Meloidogyne hapla . Cultivars presented differences in fruit production and also in the incidence of "redness". Lowest performance in production was related to the high incidence of the nematode Meloidogyne hapla. 'Oso Grande' and 'Albion' presented nematode-resistant behavior. It was possible find a relationship between the incidence of the Meloidogyne hapla nematode, and the incidence of "redness" only 'Camino Real' cultivar.

  3. Effects of Essential Oils and Plant Extracts on Hatching, Migration and Mortality of Meloidogyne incognita

    Directory of Open Access Journals (Sweden)

    S.K. Ibrahim.

    2006-12-01

    Full Text Available The nematicidal activity of the essential oil/pure components and plant extracts of naturally grown aromatic plant species against hatching, migration and mortality of the root knot nematode Meloidogyne incognita was investigated. The pure components carvacrol, thymol, and linalool at 1, 2 and 4 mg liter-1 concentrations were the most toxic against M. incognita second-stage juveniles (J2s followed by terpineol and menthone. Hatching was completely inhibited at low concentrations (2, 4 mg liter-1 of carvacrol, thymol, and linalool. Clove extracts (1 mg liter-1 of Allium sativum significantly reduced hatching activity to below 8%, followed by flower extracts of Foeniculum vulgare which reduced hatching to below 25%. These extracts were also toxic against J2s of M. incognita (LC50 43 followed by leaf extracts of Pinus pinea, Origanum syriacum, Mentha microcorphylla, Eucalyptus spp. and Citrus sinensis with an estimated LC50 of 44, 50, 65, 66 and 121 ppm respectively. Flower extracts of F. vulgare had the highest effect on J2 mortality in sand (86%. The highest concentration of essential oils (6% was detected in leaf extracts of Origanium syriacum. Over 30 major components were identified in all the plant extracts tested.

  4. Ovicidal and larvicidal activity of extracts of Opuntia ficus-indica against gastrointestinal nematodes of naturally infected sheep.

    Science.gov (United States)

    Féboli, Aline; Laurentiz, Antonio C; Soares, Suelen C S; Augusto, Jeferson G; Anjos, Luciano A; Magalhães, Lizandra G; Filardi, Rosemeire S; Laurentiz, Rosangela S

    2016-08-15

    This study describes the in vitro anthelmintic activity of extracts from Opuntia ficus indica against gastrointestinal nematodes of sheep. The anthelmintic activity was evaluated by inhibition of egg hatching, larval development and larval migration assays. The residual aqueous fractions from cladodes and fruits showed higher ovicidal activity with EC50 values of 7.2mg/mL and 1.5mg/mL, respectively. The aqueous, hexane, and ethyl acetate fractions from fruits and the aqueous fraction from cladodes inhibited 100% of larval development at the lowest concentration tested (1.56mg/mL). The crude cladode and fruit ethanolic extracts inhibited larval migration and showed EC50 values of 0.74mg/mL and 0.27mg/mL, respectively. Phytochemical screening detected high concentrations of alkaloids, tannins, flavonoids, and saponins in the fruits and cladodes. The results demonstrated that O. ficus exhibits anthelmintic activity in vitro, suggesting that, beyond its nutritional potential, this plant can also be an ally for parasite control in sheep. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Female Zebra Finches Smell Their Eggs.

    Directory of Open Access Journals (Sweden)

    Sarah Golüke

    Full Text Available Parental investment in unrelated offspring seems maladaptive from an evolutionary perspective, due to the costs of energy and resources that cannot be invested in related offspring at the same time. Therefore selection should favour mechanisms to discriminate between own and foreign offspring. In birds, much emphasis has been placed on understanding the visual mechanisms underlying egg recognition. However, olfactory egg recognition has almost been completely ignored. Here, we investigated whether female zebra finches (Taeniopygia guttata are able to discriminate between their own and a conspecific egg based on olfactory cues alone. Zebra finches are colonial-breeding songbirds. Eggs are monomorphic, i.e. without any spotting pattern, and intraspecific brood parasitism frequently occurs. In a binary choice experiment, female zebra finches were given the choice between the scent of their own and a conspecific egg. After the onset of incubation, females chose randomly and showed no sign of discrimination. However, shortly before hatching, females preferred significantly the odour of their own egg. The finding that females are capable to smell their own egg may inspire more research on the potential of olfaction involved in egg recognition, especially in cases where visual cues might be limited.

  6. Integrating toxicity risk in bird eggs and chicks: using chick down feathers to estimate mercury concentrations in eggs.

    Science.gov (United States)

    Ackerman, Joshua T; Eagles-Smith, Collin A

    2009-03-15

    The concentration of mercury (Hg) in eggs that causes reduced hatching success is regarded as a critical end point for Hg toxicity in birds. However, incorporating effects of in ovo mercury exposure on chick health and survival could improve risk assessment. We developed equations to predict Hg in eggs using Hg in chick down feathers, and vice versa, by assessing the relationship between Hg in feathers (0.5-32.4 microg g(-1) fw) and eggs (0.04-2.79 microg g(-1) fww) for three waterbird species in San Francisco Bay, CA. Feather Hg sampled from embryos of pipping eggs was highly correlated with fresh whole-egg Hg (n=94, r2 = 0.96). Additionally, using an egg microsampling technique, albumen Hg was correlated with feather Hg sampled from chicks in the same nest (n=28, r2 = 0.79). Down feather Hg in recaptured chicks (feather Hg at hatching (feathers of chicks < or =10 days of age to nonlethally predict Hg in eggs and thus provide the ability to develop exposure thresholds for eggs that incorporate in ovo Hg's effects on both egg hatchability and subsequent chick mortality.

  7. The light cycle controls the hatching rhythm in Bombyx mori via negative feedback loop of the circadian oscillator.

    Science.gov (United States)

    Tao, Hui; Li, Xue; Qiu, Jian-Feng; Liu, Heng-Jiang; Zhang, Da-Yan; Chu, Feng; Sima, Yanghu; Xu, Shi-Qing

    2017-10-01

    Hatching behavior is a key target in silkworm (Bombyx mori) rearing, especially for the control of Lepidoptera pests. According to previous research, hatching rhythms appear to be controlled by a clock mechanism that restricts or "gates" hatching to a particular time. However, the underlying mechanism remains elusive. Under 12-h light:12-h dark photoperiod (LD) conditions, the transcriptional levels of the chitinase5 (Cht5) and hatching enzyme-like (Hel) genes, as well as the enzymatic activities of their gene products, oscillated in time with ambient light cycles, as did the transcriptional levels of the cryptochrome 1, cryptochrome 2, period (per), and timeless genes, which are key components of the negative feedback loop of the circadian rhythm. These changes were related to the expression profile of the ecdysteroid receptor gene and the hatching behavior of B. mori eggs. However, under continuous light or dark conditions, the hatching behavior, the expression levels of Cht5 and Hel, as well as the enzymatic activities of their gene products, were not synchronized unlike under LD conditions. In addition, immunohistochemistry experiments showed that light promoted the translocation of PER from the cytoplasm to the nucleus. In conclusion, LD cycles regulate the hatching rhythm of B. mori via negative feedback loop of the circadian oscillator. © 2017 Wiley Periodicals, Inc.

  8. Novel bioassay demonstrates attraction of the white potato cyst nematode Globodera pallida (Stone) to non-volatile and volatile host plant cues.

    Science.gov (United States)

    Farnier, Kevin; Bengtsson, Marie; Becher, Paul G; Witzell, Johanna; Witzgall, Peter; Manduríc, Sanja

    2012-06-01

    Potato cyst nematodes (PCNs) are a major pest of solanaceous crops such as potatoes, tomatoes, and eggplants and have been widely studied over the last 30 years, with the majority of earlier studies focusing on the identification of natural hatching factors. As a novel approach, we focused instead on chemicals involved in nematode orientation towards its host plant. A new dual choice sand bioassay was designed to study nematode responses to potato root exudates (PRE). This bioassay, conducted together with a traditional hatching bioassay, showed that biologically active compounds that induce both hatching and attraction of PCNs can be collected by water extraction of incised potato roots. Furthermore, our results demonstrated that PCN also were attracted by potato root volatiles. Further work is needed to fully understand how PCNs use host plant chemical cues to orientate towards hosts. Nevertheless, the simple attraction assay used in this study provides an important tool for the identification of host-emitted attractants.

  9. Improving cold storage of subitaneous eggs of the copepod Acartia tonsa Dana from the Gulf of Mexico (Florida, USA)

    DEFF Research Database (Denmark)

    Drillet, Guillaume; Lindley, L.C.; Michels, A.

    2007-01-01

    (kanamycin sulphate and oxytetracycline HCl) on extending the shelf life of cold-stored subitaneous Acartia tonsa eggs. Also, egg development effects on the survival of the eggs were tested. Glucose did not have any significant effects on the survival of the eggs. However, the addition of antibiotics......%. However, long exposure to high concentrations of antibiotics was lethal to the copepod eggs. After more than 30 days of exposure to 100 mg L-1 of oxytetracycline, the survival of the eggs was lower than in the untreated samples. After 45 days, oxytetracycline-treated eggs (100 mg L-1) presented a hatching...

  10. Resíduos de frutos de pequi no controle do nematóide das galhas em tomateiro Pequi fruit waste in the control of root-knot nematodes in tomato

    Directory of Open Access Journals (Sweden)

    Hudson B Ribeiro

    2012-09-01

    ão indicativos de fitotoxicidade.The exocarp and external mesocarp of pequi fruit are discarded during the extraction of internal mesocarp which is the commercial part used as food. The objective of this research was to study the use of aqueous extract and of pequi ground-powder to the control of root-knot nematode (Meloidogyne javanica. From ground pequi fruit exocarp and external mesocarp were obtained the aquaeous extract and powder. Five doses of aquaeous extract (0.0; 2.5; 5; 10 or 20% were evaluated on root-knot nematode J2 (second stage juvenile hatching and mortality. The assays were carried out in entirely randomized design with 10 replications. The hatching assay was set in Petri plates with 800 nematode eggs and 10 mL of different doses of extract. During 14 days we counted the number of hatched juveniles under optical microscope. The mortality assay of root-knot nematode was evaluated putting 100 µL of each dose of extract plus 20 µL of supension containing 20 J2 in each cell Elisa plate. After 24 h was counted the number of live and dead juveniles. The pequi powder was tested in tomato plants in greenhouse in four doses (0; 7.5; 15 or 30 g/4 kg of soil in randomized blocks design with 10 replications per treatment. The pequi powder was incorporated to the soil seven days before transplanting and nematode eggs inoculation was carried out after transplanting. After 40 days we evaluated the number of galls, egg masses, eggs/root and J2 per 200 cm³ soil and the tomato shoot dry weight and height. The aquaeous extract reduced J2 hatching and increased J2 mortality. The increased application of powder doses reduced the number of galls, egg masses and eggs of root-knot nematodes per root system and the tomato shoot dry weight being a good indication of phytotoxicity.

  11. The extraembryonic serosa protects the insect egg against desiccation

    Science.gov (United States)

    Jacobs, Chris G. C.; Rezende, Gustavo L.; Lamers, Gerda E. M.; van der Zee, Maurijn

    2013-01-01

    Insects have been extraordinarily successful in occupying terrestrial habitats, in contrast to their mostly aquatic sister group, the crustaceans. This success is typically attributed to adult traits such as flight, whereas little attention has been paid to adaptation of the egg. An evolutionary novelty of insect eggs is the serosa, an extraembryonic membrane that enfolds the embryo and secretes a cuticle. To experimentally test the protective function of the serosa, we exploit an exceptional possibility to eliminate this membrane by zerknüllt1 RNAi in the beetle Tribolium castaneum. We analyse hatching rates of eggs under a range of humidities and find dramatically decreasing hatching rates with decreasing humidities for serosa-less eggs, but not for control eggs. Furthermore, we show serosal expression of Tc-chitin-synthase1 and demonstrate that its knock-down leads to absence of the serosal cuticle and a reduction in hatching rates at low humidities. These developmental genetic techniques in combination with ecological testing provide experimental evidence for a crucial role of the serosa in desiccation resistance. We propose that the origin of this extraembryonic membrane facilitated the spectacular radiation of insects on land, as did the origin of the amniote egg in the terrestrial invasion of vertebrates. PMID:23782888

  12. Spawning and hatching of endangered Gila Chub in captivity

    Science.gov (United States)

    Schultz, Andrew A.; Bonar, Scott A.

    2016-01-01

    Information on reproductive characteristics of the endangered Gila Chub Gila intermedia is largely limited and qualitative, and culture techniques and requirements are virtually unknown. Here we provide the first published data on spawning and selected reproductive and developmental characteristics of Gila Chub. Fish were brought to the laboratory in March 2003 from Sabino Creek, Arizona (12.3°C). Fish were then warmed slowly and spawned at 14.9°C, 10 d after collection. Following this initial spawning, Gila Chub spawned consistently in the laboratory without hormonal, chemical, photoperiod, temperature, or substrate manipulation during all times of the year. Spawns were noted at temperatures ranging from about 15°C to 26°C; however, we noted that Gila Chub spawned less frequently at temperatures above 24°C. Multiple spawning attempts per year per individual are probable. There was a strong, inverse relationship between time to hatch and incubation temperature. The hatch rate of eggs was high (mean = 99.43%), and larval Gila Chub accepted a variety of natural and formulated diets at first feeding. The future of Gila Chub may someday depend in part on hatchery propagation to provide specimens for restocking formerly occupied habitats and establishing refuge populations. Information from our study can aid future efforts to successfully spawn and rear Gila Chub and related species.

  13. Effects of breeder age and pre-incubation storage of eggs

    African Journals Online (AJOL)

    S..

    South African Journal of Animal Science 2005, 35 (2) ... weight, chick weight and percentage yolk weight were significantly higher in eggs ... interactions for water loss in chicks, early embryonic death, late embryonic ... in which hatching eggs are commonly stored for three to seven days prior .... The negative impacts were.

  14. Using copper sulfate on hybrid striped bass eggs to control fungus and increase survival

    Science.gov (United States)

    A major obstacle in fish hatcheries is the inevitable fungal growth on eggs. Copper sulfate (CuSO4) is commonly used for fungus control in channel catfish hatcheries that use troughs, but effectiveness on fish eggs hatched using different systems has only recently been investigated. Fish were spawn...

  15. Oxygen requirements of separated hybrid catfish female Ictalurus punctatus male I. furcatus eggs

    Science.gov (United States)

    Channel catfish Ictalurus punctatus egg masses require ambient water with over 95% air saturation to maintain maximum oxygen consumption as they near hatch. Since hybrid catfish eggs (channel catfish ' X blue catfish I. furcatus ') are often kept separated after fertilization by the addition of full...

  16. Temperature effects on egg development and larval condition in the lesser sandeel, Ammodytes marinus

    Science.gov (United States)

    Régnier, Thomas; Gibb, Fiona M.; Wright, Peter J.

    2018-04-01

    Understanding the influence of temperature on egg development and larval condition in planktonic fish is a prerequisite to understanding the phenological impacts of climate change on marine food-webs. The lesser sandeel, Ammodytes marinus (Raitt 1934), is a key trophic link between zooplankton and many piscivorous fish, sea birds and mammals in the northeast Atlantic. Temperature-egg development relationships were determined for batches of lesser sandeel eggs. Hatching began as early as 19 days post fertilisation at 11 °C and as late as 36 days post fertilisation at 6 °C, which is faster than egg development rates reported for closely related species at the lower end of the tested temperature range. The average size of newly hatched larvae decreased with increasing incubation temperatures in early hatching larvae, but this effect was lost by the middle of the hatching period. While the study revealed important temperature effects on egg development rate, predicted variability based on the range of temperatures eggs experience in the field, suggests it is only a minor contributor to the observed inter-annual variation in hatch date.

  17. Fuzzy modeling to predict chicken egg hatchability in commercial hatchery.

    Science.gov (United States)

    Peruzzi, N J; Scala, N L; Macari, M; Furlan, R L; Meyer, A D; Fernandez-Alarcon, M F; Kroetz Neto, F L; Souza, F A

    2012-10-01

    Experimental studies have shown that hatching rate depends, among other factors, on the main physical characteristics of the eggs. The physical parameters used in our work were egg weight, eggshell thickness, egg sphericity, and yolk per albumen ratio. The relationships of these parameters in the incubation process were modeled by Fuzzy logic. The rules of the Fuzzy modeling were based on the analysis of the physical characteristics of the hatching eggs and the respective hatching rate using a commercial hatchery by applying a trapezoidal membership function into the modeling process. The implementations were performed in software. Aiming to compare the Fuzzy with a statistical modeling, the same data obtained in the commercial hatchery were analyzed using multiple linear regression. The estimated parameters of multiple linear regressions were based on a backward selection procedure. The results showed that the determination coefficient and the mean square error were higher using the Fuzzy method when compared with the statistical modeling. Furthermore, the predicted hatchability rates by Fuzzy Logic agreed with hatching rates obtained in the commercial hatchery.

  18. Hookworm-like eggs in children's faecal samples from a rural area of ...

    African Journals Online (AJOL)

    Larvae of C. elegans in water drop from the coprocultive (vision through electronic loupe). Discussion. A brief review of other studies showed frequent prob- lems in the identification of hookworm eggs by micros- copy. It is often reported as misdiagnosis of hookworm eggs with other nematode species. Some researchers14- ...

  19. Volume of eggs in the clutches of Grass snake Natrix natrix and Dice snake N. tessellata: error correction

    Directory of Open Access Journals (Sweden)

    Klenina Anastasiya Aleksandrovna

    2015-12-01

    Full Text Available The authors have made a mistake in calculating the volume of eggs in the clutches of snake family Natrix. In this article we correct the error. As a result, it was revealed, that the volume of eggs positively correlates with a female length and its mass, as well as with the quantity of eggs in the clutches. There is a positive correlation between the characteristics of newborn snakes (length and mass and the volume of eggs, from which they hatched.

  20. effect of gamma radiation and parasitic nematodes on the black cut-worm agrotis ipsilon(HUFN)

    International Nuclear Information System (INIS)

    Sileem, T.M.

    2011-01-01

    The sterility effects were examined on the P1 generation of the black cutworm; Agrotis ipsilon (Hufn.) after gamma sterilization with at 0, 75, 100,125, 150,175 and 200 Gy, to identify the dose of gamma irradiation that would allow for maximum production of partially sterile P1 adults while inducing full sterility in the F1 generation. The studied effects were included the percentage mated males with untreated females, copulation duration to format spermatophores directly in the female bursa copulatrix, number of eggs /female deposited by females mated to irradiated males and egg hatch through three sequential females.The irradiated males with tested doses as well as untreated control were tested for mating successive and starting copulation at the same period of the scotophase. The mating competitiveness calculated from the direct observation in A. ipsilon males emerged from pupae irradiated at doses 75 to 200 Gy was noticed. The effect of substerilizing dose (125Gy) on certain biological aspects and reproduction was studied among parental generation, as well as immature stages were investigated throughout two successive generations. The influence of two entomopathogenic nematodes, Steinernema carpocapsae and Steinernema riobrivae on the insect management was included. Special attention was given to combined effect of F1 progeny of partially sterile males and S. Carpocapsae (All) on A .ipsilon, the combination of tested treatments at all concentrations analyzed for synergistic effect. The parasitisation efficacy of EPNs, the morbidity and mortality induced by normal IJs (i.e., IJs derived from untreated host) and the incubation time taken by normal IJs were compared with these of IJs derived from irradiated host with 125 Gy

  1. Age dependent radiation sensitivity of eggs of Dysdercus koenigii Fabricius

    International Nuclear Information System (INIS)

    Harwalkar, M.R.

    1992-01-01

    Eggs of Dysdercus koenigii Fabricius aged 0 to 2, 24, 48 and 72 hr were irradiated with X-ray doses ranging between 3 to 15 Gy to determine radiation sensitivity. It was observed that age of the eggs greatly influenced their response to radiation treatment. A dose of 6 Gy was required to prevent hatching of 0 to 2 hr old eggs but older eggs (24 and 48 hr) required 9 and 15 Gy, respectively, to bring about the same effect. At all the doses hatchability of 72 hr old irradiated eggs was much higher than those irradiated at younger age. Survival of nymphs emerging from 72 hr irradiated eggs at different dose levels was found to be dose dependent. Percentage of nymphs metamorphosing into adults decreased with increasing radiation dose received at the embryonic stage. (author). 21 refs., 2 figs

  2. Evaluation of Eucalyptus citriodora essential oil on goat gastrointestinal nematodes Avaliação do óleo essencial de Eucalyptus citriodora sobre nematóides gastrintestinais de caprinos

    Directory of Open Access Journals (Sweden)

    Iara Tersia Freitas Macedo

    2011-09-01

    Full Text Available Phytotherapy may be an alternative strategy for controlling gastrointestinal parasites. This study evaluated the anthelmintic efficacy of Eucalyptus citriodora essential oil (EcEO. The in vitro effects of EcEO were determined through testing the inhibition of egg hatching and larval development of Haemonchus contortus. EcEO was subjected to acute toxicity testing on mice, orally and intraperitoneally. The in vivo effects of EcEO were determined by the fecal egg count reduction test (FECRT in goats infected with gastrointestinal nematodes. The results showed that 5.3 mg.mL-1 EcEO inhibited egg hatching by 98.8% and 10.6 mg.mL-1 EcEO inhibited H. contortus larval development by 99.71%. The lethal doses for 50% of the mice were 4153 and 622.8 mg.kg-1, for acute toxicity orally and intraperitoneally. In the FECRT, the efficacy of EcEO and ivermectin was 66.25 and 79.16% respectively, on goat gastrointestinal nematodes eight days after treatment. EcEO showed in vitro and in vivo anthelmintic activity.Fitoterapia pode ser uma estratégia alternativa para o controle de parasitas gastrintestinais. Este estudo avaliou a eficácia anti-helmintica do óleo essencial de Eucalyptus citriodora (OeEc. Os efeitos in vitro do OeEc foram determinados através do teste de eclosão de ovos e inibição do desenvolvimento larvar de Haemonchus contortus. O OeEc foi submetido ao teste de toxicidade aguda oral e intraperitoneal, em camundongos. Os efeitos in vivo do OeEc foram avaliados através do teste de redução da contagem de ovos nas fezes (FECRT com caprinos infectados com nematóides gastrintestinais. Os resultados mostraram que 5,3 mg.mL-1 OeEc inibiram 98,8% a eclosão de ovos e 10,6 mg.mL-1 OeEc inibiram 99,71% o desenvolvimento larvar de H. contortus. As doses letais para 50% dos camundongos foram de 4153 e 622,8 mg.kg-1 pela via oral e intraperitoneal. No FECRT, a eficácia de OeEc e ivermectina foi de 66,25 e 79,16%, respectivamente, em caprinos 8 dias

  3. Physiological ecology of desert iguana (Dipsosaurus dorsalis) eggs: temperature and water relations

    Energy Technology Data Exchange (ETDEWEB)

    Muth, A.

    1980-12-01

    The soil environment imposes constraints on the timing of oviposition and the location of suitable sites for egg burrows of the desert iguana (Dipsosaurus dorsalis). The effects of temperature and water potential on the developmental period and hatching success of eggs were determined. Eggs hatch normally between 28/sup 0/ and 38/sup 0/C at environmental water potentials between -50 and -1500 kPa. Predictions were derived for the timing and placement of egg clutches based on soil water potential and temperature profiles measured in the field and on the results of laboratory incubation experiments. The results suggest that egg burrows should be located at depths >22 cm in washes or possibly in sparsely vegetated areas away from creosote bushes. The biogeography of desert iguanas within the United States is discussed in relation to soil environments and tolerances of eggs. The physical factors affecting incubation may limit the geographical range of desert iguanas.

  4. Characterisation of some Ornithobacterium rhinotracheale strains and examination of their transmission via eggs.

    Science.gov (United States)

    Varga, J; Fodor, L; Makrai, L

    2001-01-01

    The biochemical characteristics and antibiotic susceptibility of 12 Ornithobacterium rhinotracheale strains isolated from chickens and turkeys suffering from respiratory clinical signs and the survival of some isolates on egg-shell and within chicken eggs during hatching were examined. All O. rhinotracheale strains showed typical biochemical characteristics. Among the 16 drugs examined, penicillin G, ampicillin (MICs ranging from tiamulin (MICs varied from colistin) or not at all (apramycin, spectinomycin, polymyxin B). At 37 degrees C, O. rhinotracheale did not survive on egg-shell for more than 24 hours, while upon inoculation into embryonated chicken eggs it killed embryos by the ninth day, and from the 14th day post-inoculation no O. rhinotracheale could be cultured from the eggs at all. These results suggest that O. rhinotracheale is not transmitted via eggs during hatching.

  5. Ijuhya vitellina sp. nov., a novel source for chaetoglobosin A, is a destructive parasite of the cereal cyst nematode Heterodera filipjevi.

    Directory of Open Access Journals (Sweden)

    Samad Ashrafi

    Full Text Available Cyst nematodes are globally important pathogens in agriculture. Their sedentary lifestyle and long-term association with the roots of host plants render cyst nematodes especially good targets for attack by parasitic fungi. In this context fungi were specifically isolated from nematode eggs of the cereal cyst nematode Heterodera filipjevi. Here, Ijuhya vitellina (Ascomycota, Hypocreales, Bionectriaceae, encountered in wheat fields in Turkey, is newly described on the basis of phylogenetic analyses, morphological characters and life-style related inferences. The species destructively parasitises eggs inside cysts of H. filipjevi. The parasitism was reproduced in in vitro studies. Infected eggs were found to harbour microsclerotia produced by I. vitellina that resemble long-term survival structures also known from other ascomycetes. Microsclerotia were also formed by this species in pure cultures obtained from both, solitarily isolated infected eggs obtained from fields and artificially infected eggs. Hyphae penetrating the eggshell colonised the interior of eggs and became transformed into multicellular, chlamydospore-like structures that developed into microsclerotia. When isolated on artificial media, microsclerotia germinated to produce multiple emerging hyphae. The specific nature of morphological structures produced by I. vitellina inside nematode eggs is interpreted as a unique mode of interaction allowing long-term survival of the fungus inside nematode cysts that are known to survive periods of drought or other harsh environmental conditions. Generic classification of the new species is based on molecular phylogenetic inferences using five different gene regions. I. vitellina is the only species of the genus known to parasitise nematodes and produce microsclerotia. Metabolomic analyses revealed that within the Ijuhya species studied here, only I. vitellina produces chaetoglobosin A and its derivate 19-O-acetylchaetoglobosin A. Nematicidal

  6. Ijuhya vitellina sp. nov., a novel source for chaetoglobosin A, is a destructive parasite of the cereal cyst nematode Heterodera filipjevi.

    Science.gov (United States)

    Ashrafi, Samad; Helaly, Soleiman; Schroers, Hans-Josef; Stadler, Marc; Richert-Poeggeler, Katja R; Dababat, Abdelfattah A; Maier, Wolfgang

    2017-01-01

    Cyst nematodes are globally important pathogens in agriculture. Their sedentary lifestyle and long-term association with the roots of host plants render cyst nematodes especially good targets for attack by parasitic fungi. In this context fungi were specifically isolated from nematode eggs of the cereal cyst nematode Heterodera filipjevi. Here, Ijuhya vitellina (Ascomycota, Hypocreales, Bionectriaceae), encountered in wheat fields in Turkey, is newly described on the basis of phylogenetic analyses, morphological characters and life-style related inferences. The species destructively parasitises eggs inside cysts of H. filipjevi. The parasitism was reproduced in in vitro studies. Infected eggs were found to harbour microsclerotia produced by I. vitellina that resemble long-term survival structures also known from other ascomycetes. Microsclerotia were also formed by this species in pure cultures obtained from both, solitarily isolated infected eggs obtained from fields and artificially infected eggs. Hyphae penetrating the eggshell colonised the interior of eggs and became transformed into multicellular, chlamydospore-like structures that developed into microsclerotia. When isolated on artificial media, microsclerotia germinated to produce multiple emerging hyphae. The specific nature of morphological structures produced by I. vitellina inside nematode eggs is interpreted as a unique mode of interaction allowing long-term survival of the fungus inside nematode cysts that are known to survive periods of drought or other harsh environmental conditions. Generic classification of the new species is based on molecular phylogenetic inferences using five different gene regions. I. vitellina is the only species of the genus known to parasitise nematodes and produce microsclerotia. Metabolomic analyses revealed that within the Ijuhya species studied here, only I. vitellina produces chaetoglobosin A and its derivate 19-O-acetylchaetoglobosin A. Nematicidal and nematode

  7. Effects of Hen Age and Egg Weight Class on the Hatchability of Free Range Indigenous Chicken Eggs

    Directory of Open Access Journals (Sweden)

    AM Abudabos

    Full Text Available ABSTRACT In total, 806 eggs of free-range Hassawi indigenous chickens were collected from local farm in Saudi Arabia. Eggs were weekly collected for 11 weeks. Initial egg weight (IEW was recorded, and eggs were graded into four classes (A: 35-40 g, B: 40-45 g, C: 45-50 g, and D: 50-55 g. Eggs were stored for seven days at 75-80% relative humidity and 14-16 C, after which egg weight losses (WL0 were calculated. During incubation, eggs were weighed on days 7 (W7 and 14 (W14, and egg weight losses on days 7 (WL7 and 14 (WL14, and total loss (WL0-14 were calculated. Hatchling weight (CW was measured. The proportion of CW relative to egg weight loss (WL on days0, 7 and 14 days of incubation (CW:WL0; CW:WL7 and CW:WL14, respectively, and break out analyses, fertility (F,total hatchability (HC and hatchability of fertile eggs (HF were also calculated. IEW decreased (p<0.05 with hen age. Stored egg weight (SEW were decreased as hen age increased (p<0.05. WL7, WL14 and WL0-14 showed significant differences (p<0.001 and increased up to first six-week of egg collection time. Hen age affected CW:WL before incubation, and on days 7 and 14 of incubation. Fertility (F was affected (p<0.05 in unpredicted way of increasing and decreasing by hen age. Egg weight class affected SEW, W7and W14 (p<0.001. Class D eggs were the highest weight. Class C eggs had highest HC. In summary, hatching eggs of Hassawi hens were affected by hen age and egg weight in randomly increase and decrease .

  8. Effect of cadmium, lead and arsenic on the oviposition, hatching and embryonic survival of Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Ansaldo, Martin; Nahabedian, Daniel E.; Di Fonzo, Carla; Wider, Eva A.

    2009-01-01

    Biomphalaria glabrata is a widespread freshwater gastropod mollusc. The easy aquaculture of these organisms allow its use as an accessible tool for contamination bioassays. B. glabrata showed marked metabolic responses when exposed to cadmium, lead and arsenic. Those responses could also affect the reproduction of the snails. Taking into account this hypothesis, B. glabrata were exposed for 96 h (acute laboratory bioassays) to different concentrations of cadmium (0.1, 0.05 and 0 mg/L), lead (0.5, 0.1, 0.05 and 0 mg/L) and arsenic (0.5, 0.1, 0.05 and 0 mg/L). Snails were removed from the aquaria while eggs were left in the same contaminant concentrations. The effect of the assayed toxicants on snail reproduction was registered as the alterations of the total number of laid eggs (TNLE), hatching time and embryonic survival. At 0.10 mg/L cadmium significantly decreased the TNLE (p < 0.05) and no embryos survived. The lowest assayed level (0.05 mg/L) of cadmium, delayed the hatching time twice when it was compared with the control group (p < 0.01). Lead decreased the TNLE at 0.5 mg/L level (p < 0.01). The other assayed doses (0.05 and 0.10 mg/L) also decreased embryonic survival significantly (p < 0.05 and p < 0.01 respectively) and extended twice the time to hatching (p < 0.01). The 0.50 mg/L level killed all embryos. Arsenic at all studied concentrations decreased the TNLE (p < 0.05) while the hatching time was increased by 50%. Embryo survival only decreased at the highest level (0.5 mg/L) of arsenic assayed. In summary, the acute exposure (96 h) to cadmium lead and arsenic, altered the reproduction of B. glabrata, modifying the TNLE, hatching time and embryonic survival

  9. Genetic parameters and relationships of faecal worm egg count with ...

    African Journals Online (AJOL)

    The costs of internal parasite control and treatment are potentially very high in grazing sheep. Faecal worm egg count (FEC) has been suggested as a suitable criterion for selection for resistance to nematode infestation in livestock. Genetic parameter estimates for FEC and its relationship with wool traits were assessed in ...

  10. The relationships between faecal worm egg count and subjectively ...

    African Journals Online (AJOL)

    Subjectively assessed wool and conformation traits form part of the selection objective in wool sheep enterprises. The present study investigated the genetic, phenotypic and environmental correlations for nematode resistance (using faecal worm egg count (FEC)) with subjectively assessed wool and conformation traits.

  11. A new large egg type from the marine live feed calanoid copepod Acartia tonsa (Dana)-Perspectives for selective breeding of designer feed for hatcheries

    DEFF Research Database (Denmark)

    Hammervold, Stian Halsen; Glud, Ronnie N.; Evjemo, Jan Ove

    2015-01-01

    correspondingly large, and the copepods remained large when developing into adulthood. The fact that copepods hatched from large eggs were fertile indicates no chromosomal abnormalities and suggests that this egg type represents the upper tail end of eggs in a classical normal distribution of size vs. frequency...

  12. Hatching response to temperature along a latitudinal gradient by the fairy shrimp Branchinecta lindahli (Crustacea; Branchiopoda; Anostraca in culture conditions

    Directory of Open Access Journals (Sweden)

    D. Christopher Rogers

    2014-08-01

    Full Text Available Branchinecta lindahli is a broadly distributed fairy shrimp, reported from a range of temporary wetland habitat types in arid western North America. This species’ eggs hatch after the habitat dries, refills from seasonal rain, and receives a strong cold shock during the winter low temperatures. I studied phenotypic variation in temperature responses in cultures collected from four populations across 8° of latitude with low average temperatures ranging from -8 to 8°C. Time to maturation, mature body size and first clutch size decreased, as temperature increased, with only minor body size variability at mortality, regardless of culture origin. No variation in individual egg size was observed, demonstrating that body size is sacrificed to produce at least a few normal eggs during unfavourable years. Latitudinal variation in hatching temperature demonstrated a pattern of adaptive significance, with some overlap between regional temperature hatching cues.  Phenotypic hatching temperature and growth rate responses may cause genetic segregation, selecting one cohort for warmer, dryer years and one cohort for cooler, wetter years.  Drier year selected cohorts can exploit habitats that have shorter hydroperiods even in wet years. This may lead to population specialisation and speciation by adapting to more extreme habitats

  13. Nematode cholinergic pharmacology

    International Nuclear Information System (INIS)

    Segerberg, M.A.

    1989-01-01

    Nematode acetylcholine (ACh) receptors were characterized using both biochemical and electrophysiological techniques, including: (1) receptor binding studies in crude homogenates of the free-living nematode Caenorhabditis elegans and the parasitic nematode Ascaris lumbricoides with the high-affinity probe [ 3 H]N-methylscopolamine ([ 3 H]NMS) which binds to muscarinic receptors in many vertebrate and invertebrate tissues (2) measurement of depolarization and contraction induced by a variety of cholinergic agents, including N-methylscopolamine (NMS), in an innervated dorsal muscle strip preparation of Ascaris; (3) examination of the antagonistic actions of d-tubocurarine (dTC) and NMS at dorsal neuromuscular junction; (4) measurement of input resistance changes in Ascaris commissural motorneurons induced by ACh, dTC, NMS, pilocarpine and other cholinergic drugs

  14. Effect of cryopreservation on the pre-hatching behavior in the Mexican fruit fly Anastrepha ludens Loew (Diptera, Tephritidae).

    Science.gov (United States)

    Rajamohan, Arun; Rinehart, Joseph P; Leopold, Roger A

    2018-02-01

    In a sampling of untreated embryos of the economically important fruit pest species, Anastrepha ludens, the cumulative hatch percentage in the lab was noted to be ∼85%. Approximately 70% of the larvae had eclosed through the posterior pole of the egg. This process is effected by the act of Pole Reversal (PR) of the fully developed pre-hatch larva from the wider anterior to the narrower posterior pole of the egg. Investigation of the effects of cryopreservation and various pretreatments prior to cryostorage on the PR behavior was prompted by the observation of significantly lower proportion of cryopreserved embryos exhibiting the PR behavior. Pretreatments (dechorionation and permeabilization) followed by vitrification resulted in delayed hatching, reflecting a slower embryonic development rate of ∼10 h. A smaller proportion of the treated embryos either eclosed from the anterior end of the egg or did not eclose at all despite complete development and prehatch gnawing activity. In the untreated controls, 24.0% of the embryos eclosed from the anterior pole. After permeabilization and cryopreservation, 83% and 55% (adjusted hatch) of the embryos were noted to hatch this way, respectively. An analysis of the hatch count after the treatments shows that factors contributing to the embryos' inability to properly invert polarity is not solely due to cryopreservation but also due to the pretreatment procedures including dechorionation and permeabilization. In fact, the permeabilization pre-treatment contributed the highest to this phenomenon lending support to the view that chemical toxicity rather than physical effects of cryopreservation play a major role in post-cryopreservation effects. Published by Elsevier Inc.

  15. Bacterial Colonization of Cod (Gadus morhua L.) and Halibut (Hippoglossus hippoglossus) Eggs in Marine Aquaculture

    OpenAIRE

    Hansen, Geir Høvik; Olafsen, Jan A.

    1989-01-01

    Aquaculture has brought about increased interest in mass production of marine fish larvae. Problems such as poor egg quality and mass mortality of fish larvae have been prevalent. The intensive incubation techniques that often result in bacterial overgrowth on fish eggs could affect the commensal relationship between the indigenous microflora and opportunistic pathogens and subsequently hamper egg development, hatching, larval health, and ongrowth. Little information about the adherent microf...

  16. Isolation of Fungi from Heterodera glycines and in vitro Bioassays for Their Antagonism to Eggs.

    Science.gov (United States)

    Meyer, S L; Huettel, R N; Sayre, R M

    1990-10-01

    Twenty fungi were assayed in vitro for antagonism to eggs of Heterodera glycines. Eight of the fungi were isolated from cysts or eggs of H. glycines during the current study, one was isolated from Panagrellus redivivus, and eleven were obtained from other researchers or collections. The bioassays were conducted on eggs from nematodes that had been grown monoxenically on excised root tips. Phoma chrysanthemicola, one strain of Verticillium chlamydosporium, and one strain of V. lecanii caused a decrease (P Trichoderma polysporum infected live eggs but enhanced (P Fusarium sp., Neocosmospora vasinfecta, Scytalidium fulvum, Trichoderma harzianum (two strains), V. chlamydosporium (one strain), V. lecanii (three strains), and an unidentified fungus did not measurably affect egg viability, even though hyphae of five of these fungi were seen in live eggs. The bioassay provides a useful step in the selection of a biological control agent for this major nematode pest.

  17. Characteristics and Efficacy of a Sterile Hyphomycete (ARF18), a New Biocontrol Agent for Heterodera glycines and Other Nematodes

    OpenAIRE

    Kim, D. G.; Riggs, R. D.

    1991-01-01

    A filamentous, nonsporulating fungus, designated Arkansas Fungus 18 (ARF18), was isolated from 9 of 95 populations of Heterodera glycines, the soybean cyst nematode, in Arkansas. In petri dishes, ARF18 parasitized 89% of H. glycines eggs in cysts. The fungus also infected eggs of Meloidogyne incognita and eggs in cysts of Cactodera betulae, H. graminophila, H. lespedezae, H. leuceilyma, H. schachtii, and H. trifolii. In pot tests, reproduction of SCN was 70% less in untreated field soil that ...

  18. Propagation of planktonic copepods: production and mortality of eggs

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Møhlenberg, Flemming; Tiselius, Peter

    1988-01-01

    Data on fecundity and egg mortality of neritic copepods were collected in various seasons, areas and under various hydrographical conditions. On a seasonal basis variations in fecundity (F) were related to temperature rather than to the abundance of phytoplankton (P). However, a strong correlation...... between F and P was evident when water column stability varied horisontally or temporally (i.e. at a tidal front or subsequent to a storm). Estimated specific egg-mortalities were variable and occasionally very severe, up to 9.1 d−1, implying that down to 10−4% of the eggs survive to hatching...

  19. Observations on development of artemia eggs irradiated on earth

    International Nuclear Information System (INIS)

    He Jian; Zhou Qiling; Xing Guoren; Zheng Decun; Su Ruizhen; Chen Qu'e

    1990-01-01

    For accompanying with space radiobiological studies, dry eggs of native Artemia were irradiated in the laboratory by 14 MeV fast neutrons and 60 Co γ-rays, and their development was then followed. Doses of the fast neutrons used were 10, 50, 100, 200, 400, 600, 800 and 1000 Gy, and those of γ-rays were 50, 100, 500, 1000 and 2000 Gy respectively. The irradiated eggs, together with the control, were stored at 4 deg C before incubation and observations. The results are as follows: (1) A significant delay of early development was seen in eggs irradiated by both radiatoins. (2) The rates of emergence and hatching decreased with the increase of the doses, and went down further after the prolongation of egg-storage at 4 deg C. (3) The mortality peak of the larvae hatched from irradiated eggs appeared within 2-5 days after hatching, and the RBE's of the fast neutrons, for LD 50 , comparing with the γ-rays were found to be: 1.80 on the 3rd day, 2.44 on the 4th day, and 2.27 on the 5th day

  20. Evaluation of the toxicity and efficacy of hydrogen peroxide treatments on eggs of warm and cool water fishes

    Science.gov (United States)

    Rach, J.J.; Gaikowski, M.P.; Howe, G.E.; Schreier, Theresa M.

    1998-01-01

    The use of hydrogen peroxide in aquaculture is growing and there is a need to develop fundamental guidelines to effectively treat diseased fish. The safety (toxicity) of hydrogen peroxide treatments was determined on eggs of representative warm- and coolwater fish species. Eggs of northern pike (Esox lucius), walleye (Stizostedion vitreum), yellow perch (Pel ca flavescens), white sucker (Catostomus commersoni), lake sturgeon (Acipenser fulvescens), paddlefish (Polyodon spathula), common carp (Cyprinus carpio), and channel catfish (Ictalurus punctatus) were cultured in egg jars or aquaria. Treatments were initiated with non-eyed eggs and continued until all viable eggs had hatched. Eggs were treated daily for 15 min Monday through Friday with either 0, 500, 1000, 3000, or 6000 mu l l(-1) of hydrogen peroxide. For all species, the mean percent hatch was greater in eggs treated with 1000 mu l l(-1) hydrogen peroxide for 15 min than in the untreated controls. Common carp, lake sturgeon, and paddlefish were the least sensitive to hydrogen peroxide with percent hatch ranging from 40 to 48% in the 6000 mu l l(-1) hydrogen peroxide treatment. Fungal infections reduced or eliminated the hatch in most controls whereas nearly all treated eggs remained free of infection; hydrogen peroxide inhibited fungal infections on fish eggs. (C) 1998 Elsevier Science B.V. All rights reserved.

  1. Caenorhabditis elegans Egg-Laying Detection and Behavior Study Using Image Analysis

    Directory of Open Access Journals (Sweden)

    Palm Megan

    2005-01-01

    Full Text Available Egg laying is an important phase of the life cycle of the nematode Caenorhabditis elegans (C. elegans. Previous studies examined egg-laying events manually. This paper presents a method for automatic detection of egg-laying onset using deformable template matching and other morphological image analysis techniques. Some behavioral changes surrounding egg-laying events are also studied. The results demonstrate that the computer vision tools and the algorithm developed here can be effectively used to study C. elegans egg-laying behaviors. The algorithm developed is an essential part of a machine-vision system for C. elegans tracking and behavioral analysis.

  2. Nervous system disruption and concomitant behavioral abnormality in early hatched pufferfish larvae exposed to heavy oil.

    Science.gov (United States)

    Kawaguchi, Masahumi; Sugahara, Yuki; Watanabe, Tomoe; Irie, Kouta; Ishida, Minoru; Kurokawa, Daisuke; Kitamura, Shin-Ichi; Takata, Hiromi; Handoh, Itsuki C; Nakayama, Kei; Murakami, Yasunori

    2011-08-01

    Spills of heavy oil (HO) over the oceans have been proven to have an adverse effect on marine life. It has been hypothesized that exposure of early larvae of sinking eggs to HO leads largely to normal morphology, whereas abnormal organization of the developing neural scaffold is likely to be found. HO-induced disruption of the nervous system, which controls animal behavior, may in turn cause abnormalities in the swimming behavior of hatched larvae. To clarify the toxicological effects of HO, we performed exposure experiments and morphological and behavioral analyses in pufferfish (Takifugu rubripes) larvae. Fertilized eggs of pufferfish were exposed to 50 mg/L of HO for 8 days and transferred to fresh seawater before hatching. The hatched larvae were observed for their swimming behavior, morphological appearance, and construction of muscles and nervous system. In HO-exposed larvae, we did not detect any anomaly of body morphology. However, they showed an abnormal swimming pattern and disorganized midbrain, a higher center controlling movement. Our results suggest that HO-exposed fishes suffer developmental disorder of the brain that triggers an abnormal swimming behavior and that HO may be selectively toxic to the brain and cause physical disability throughout the life span of these fishes.

  3. THE EFFECT OF IMMERSION LENGTH IN PAPAYA LEAF SOLUTION (CARICA PAPAYA L. TOWARD FERTILIZATION AND HATCHING OF IRIDESCENT SHARKS (PANGASIANODON HYPOPHTHALMUS S.

    Directory of Open Access Journals (Sweden)

    Eka S.H.

    2018-02-01

    Full Text Available Iridescent sharks is one kind of freshwater fish that is quite economical. However, the availability of the fish eggs is rather problematic due to the hatcheries, i.e. the adhesive nature of the eggs. Papaya leaves contain papain enzymes that can reduce the adhesive nature of eggs. The purpose of this study was to determine the effect of papaya leaf solution with different immersion period on the successful hatching of the iridescent sharks (P. hypophthalmus. This study was conducted experimentally using a complete randomized design. There were five treatments, i.e. (K 0 seconds, (A 30 seconds, (B 60 seconds, (C 90 seconds, (D 120 seconds, and (E 150 seconds with three-time repetition. The result of this study shows that the best hatching (80.31% happens to the eggs immersed in papaya leaf solution for 60 seconds (treatment B.

  4. Keeping eggs warm: thermal and developmental advantages for parasitic cuckoos of laying unusually thick-shelled eggs.

    Science.gov (United States)

    Yang, Canchao; Huang, Qiuli; Wang, Longwu; Du, Wei-Guo; Liang, Wei; Møller, Anders Pape

    2018-01-02

    Obligate brood parasites have evolved unusually thick-shelled eggs, which are hypothesized to possess a variety of functions such as resistance to puncture ejection by their hosts. In this study, we tested the hypothesis that obligate brood parasites lay unusually thick-shelled eggs to retain more heat for the developing embryo and thus contribute to early hatching of parasite eggs. By doing so, we used an infrared thermal imaging system as a non-invasive method to quantify the temperature of eggshells of common cuckoos (Cuculus canorus) and their Oriental reed warbler (Acrocephalus orientalis) hosts in an experiment that artificially altered the duration of incubation. Our results showed that cuckoo eggshells had higher temperature than host eggs during incubation, but also less fluctuations in temperature during incubation disturbance. Therefore, there was a thermal and hence a developmental advantage for brood parasitic cuckoos of laying thick-shelled eggs, providing another possible explanation for the unusually thick-shelled eggs of obligate brood parasites and earlier hatching of cuckoo eggs compared to those of the host.

  5. Keeping eggs warm: thermal and developmental advantages for parasitic cuckoos of laying unusually thick-shelled eggs

    Science.gov (United States)

    Yang, Canchao; Huang, Qiuli; Wang, Longwu; Du, Wei-Guo; Liang, Wei; Møller, Anders Pape

    2018-02-01

    Obligate brood parasites have evolved unusually thick-shelled eggs, which are hypothesized to possess a variety of functions such as resistance to puncture ejection by their hosts. In this study, we tested the hypothesis that obligate brood parasites lay unusually thick-shelled eggs to retain more heat for the developing embryo and thus contribute to early hatching of parasite eggs. By doing so, we used an infrared thermal imaging system as a non-invasive method to quantify the temperature of eggshells of common cuckoos ( Cuculus canorus) and their Oriental reed warbler ( Acrocephalus orientalis) hosts in an experiment that artificially altered the duration of incubation. Our results showed that cuckoo eggshells had higher temperature than host eggs during incubation, but also less fluctuations in temperature during incubation disturbance. Therefore, there was a thermal and hence a developmental advantage for brood parasitic cuckoos of laying thick-shelled eggs, providing another possible explanation for the unusually thick-shelled eggs of obligate brood parasites and earlier hatching of cuckoo eggs compared to those of the host.

  6. An insight into the heat and mass transfer mechanisms of eggshells hatching broiler chicks and its effects to the hatcher environment.

    Science.gov (United States)

    Romanini, C E B; Exadaktylos, V; Hong, S W; Tong, Q; McGonnell, I; Demmers, T G M; Bergoug, H; Guinebretière, M; Eterradossi, N; Roulston, N; Verhelst, R; Bahr, C; Berckmans, D

    2015-02-01

    Thermodynamic study of incubated eggs is an important component in the optimisation of incubation processes. However, research on the interaction of heat and moisture transfer mechanisms in eggs is rather limited and does not focus on the hatching stage of incubation. During hatch, both the recently hatched chick and the broken eggshell add extra heat and moisture contents to the hatcher environment. In this study, we have proposed a novel way to estimate thermodynamically the amount of water evaporated from a broken eggshell during hatch. The hypothesis of this study considers that previously reported drops in eggshell temperature during hatching of chicks is the result remaining water content evaporating from the eggshell, released on the inner membrane by the recently hatched wet chick, just before hatch. To reproduce this process, water was sprayed on eggshells to mimic the water-fluid from the wet body of a chick. For each sample of eggshell, the shell geometry and weight, surface area and eggshell temperature were measured. Water evaporation losses and convection coefficient were calculated using a novel model approach considering the simultaneous heat and mass transfer profiles in an eggshell. The calculated average convective coefficient was 23.9 ± 7.5 W/m(2) °C, similar to previously reported coefficients in literature as a function of 0.5-1m/s air speed range. Comparison between measured and calculated values for the water evaporation showed 68% probability accuracy, associated to the use of an experimentally derived single heat transfer coefficient. The results support our proposed modelling approach of heat and mass transfer mechanisms. Furthermore, by estimating the amount of evaporated water in an eggshell post-hatch, air humidity levels inside the hatcher can be optimised to ensure wet chicks dry properly while not dehydrating early hatching chicks. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Identification of double-yolked duck egg using computer vision.

    Directory of Open Access Journals (Sweden)

    Long Ma

    Full Text Available The double-yolked (DY egg is quite popular in some Asian countries because it is considered as a sign of good luck, however, the double yolk is one of the reasons why these eggs fail to hatch. The usage of automatic methods for identifying DY eggs can increase the efficiency in the poultry industry by decreasing egg loss during incubation or improving sale proceeds. In this study, two methods for DY duck egg identification were developed by using computer vision technology. Transmittance images of DY and single-yolked (SY duck eggs were acquired by a CCD camera to identify them according to their shape features. The Fisher's linear discriminant (FLD model equipped with a set of normalized Fourier descriptors (NFDs extracted from the acquired images and the convolutional neural network (CNN model using primary preprocessed images were built to recognize duck egg yolk types. The classification accuracies of the FLD model for SY and DY eggs were 100% and 93.2% respectively, while the classification accuracies of the CNN model for SY and DY eggs were 98% and 98.8% respectively. The CNN-based algorithm took about 0.12 s to recognize one sample image, which was slightly faster than the FLD-based (about 0.20 s. Finally, this work compared two classification methods and provided the better method for DY egg identification.

  8. Exposing broiler eggs to green, red and white light during incubation.

    Science.gov (United States)

    Archer, G S

    2017-07-01

    Previous work has shown that exposing broiler eggs to white light during incubation can improve hatchability and post-hatch animal welfare. It was hypothesized that due to how different wavelengths of light can affect avian physiology differently, and how pigmented eggshells filter light that different monochromatic wavelengths would have differential effects on hatchability and post-hatch animal welfare indicators. To determine, we incubated chicken eggs (n=6912) under either no light (dark), green light, red light or white light; the light level was 250 lux. White and red light were observed to increase hatch of fertile (P0.05). Fear response of during isolation and tonic immobility was reduced (P0.05) from dark incubated broilers. All light incubated broilers had lower (Phatchery efficiency and post-hatch animal welfare at the same time.

  9. EGG PRODUCTION AND HATCHABILITY OF LOCAL DUCKS UNDER SEMI INTENSIVE VS EXTENSIVE MANAGEMENTS

    Directory of Open Access Journals (Sweden)

    P. Widiyaningrum

    2016-06-01

    Full Text Available The study aimed to compare the egg production and hatchability of local ducks under different management systems, namely semi-intensive and extensive. The research conducted was an experimental one-way classification with two treatments. Each treatment used 15 male and 120 females (mating ratio 1:8, and ducks aged 13-14 months. Eggs production was recorded during three weeks period. About 300 eggs were selected from each treatment to be hatched. Fertility was observed at 4th days of hatching process using egg candler. Data of eggs production, eggs weight, fertility, and hatchability were analyzed using unpaired two sample Student’s t-test. The results showed that average of egg weight, fertility and hatchability were not different under two management system, but egg production in the semi-intensive maintenance was significantly higher (P<0.05 than those in the extensive system. Egg production in the semi-intensive was 12.3% higher than those in the extensive. In conclusion, the semi-intensive system that is applied in this study the number of eggs production but did not affect the average of egg weight, fertility and hatchability.

  10. PATHOGENICITY, DEVELOPMENT AND REPRODUCTION OF THE ENTOMOPATHOGENIC NEMATODE Steinernema sp., IN MEALWORM Tenebrio molitor

    Directory of Open Access Journals (Sweden)

    Yuliantoro Baliadi

    2011-10-01

    Full Text Available The pathogenicity, development and reproduction of Steinernema sp., isolate Skpr-20/Str, were studied using Tenebrio molitor. Results revealed that pathogenicity, development and reproduction were significantly influenced by nematode doses. Although the number of invading IJs increased with increasing dose, percentage penetration declined. The IJs reached adulthood within 3 days. Females laid eggs from day 4-7. All eggs remaining inside uterus develop inside the maternal body. The first female bearing endotokia matricida was observed on day 5. In a sand-based assay, nematode was more pathogenic at lower dose instead of higher ones, where optimum dose was 80 nematodes per larva and average number of progeny per female was 5438. Under crowded conditions, development proceeds to IJ stage instead of the J3. The average length and width decreased with increasing of nematode doses. The IJ produced in cadavers infested with 640 nematodes per larva was significantly smaller (492 ± 6.4 µm than offspring from other doses. The number of days which nematodes first emerged from the cadavers decreased with increasing dose. IJ first emerged at the average of 10-13 days at high IJ densities. It is concluded that the wide experimental characteristic of EPNs is also true for Steinernema sp., isolate Skpr-20/Str.

  11. Fatal embryo chondral damage associated with fluoroquinolones in eggs of threatened avian scavengers

    International Nuclear Information System (INIS)

    Lemus, J.A.; Blanco, G.; Arroyo, B.; Martinez, F.; Grande, J.

    2009-01-01

    Stabled livestock reared in housed conditions are often subjected to intensive treatments with veterinary drug, which residues may be present in livestock meat ingested by scavengers, but nothing is known about their presence in eggs of wild birds and their potential detrimental effects on breeding success. We searched for residues of veterinary drugs and other toxicants in infertile and embryonated unhatched eggs of griffon vultures (Gyps fulvus) and red kites (Milvus milvus), two threatened avian scavengers. Quinolones (ciprofloxacin and enrofloxacin) were found in most unhatched eggs of both scavenger species clearly associated with severe alterations in the development of embryo cartilage and bones that could preclude embryo movements and subsequently normal development, pre-hatch position and successful hatching. The detrimental effects on developing eggs of veterinary drugs from livestock operations may help to explain reduced breeding success of avian scavengers. - Fluoroquinolones used in livestock farming and found in eggs of avian scavenger caused severe alterations in embryo cartilage and bone development.

  12. Fatal embryo chondral damage associated with fluoroquinolones in eggs of threatened avian scavengers

    Energy Technology Data Exchange (ETDEWEB)

    Lemus, J.A. [Departamento de Ecologia Evolutiva, Museo Nacional de Ciencias Naturales (CSIC), J. Gutierrez Abascal 2, 28006 Madrid (Spain); Blanco, G., E-mail: gublanco2@yahoo.e [Departamento de Ecologia Evolutiva, Museo Nacional de Ciencias Naturales (CSIC), J. Gutierrez Abascal 2, 28006 Madrid (Spain); Arroyo, B.; Martinez, F.; Grande, J. [Departamento de Ecologia Evolutiva, Museo Nacional de Ciencias Naturales (CSIC), J. Gutierrez Abascal 2, 28006 Madrid (Spain)

    2009-08-15

    Stabled livestock reared in housed conditions are often subjected to intensive treatments with veterinary drug, which residues may be present in livestock meat ingested by scavengers, but nothing is known about their presence in eggs of wild birds and their potential detrimental effects on breeding success. We searched for residues of veterinary drugs and other toxicants in infertile and embryonated unhatched eggs of griffon vultures (Gyps fulvus) and red kites (Milvus milvus), two threatened avian scavengers. Quinolones (ciprofloxacin and enrofloxacin) were found in most unhatched eggs of both scavenger species clearly associated with severe alterations in the development of embryo cartilage and bones that could preclude embryo movements and subsequently normal development, pre-hatch position and successful hatching. The detrimental effects on developing eggs of veterinary drugs from livestock operations may help to explain reduced breeding success of avian scavengers. - Fluoroquinolones used in livestock farming and found in eggs of avian scavenger caused severe alterations in embryo cartilage and bone development.

  13. Stage-specific mortality of Baltic cod ( Gadus morhua L.) eggs

    DEFF Research Database (Denmark)

    Wieland, Kai; Hinrichsen, H.H.; Grønkjær, P.

    2000-01-01

    A study on cod egg mortality was carried out in the Bornholm Basin (southern central Baltic Sea) toward the end of July 1996. An initial egg aggregation marked by a satellite-tracked drifter buoy was sampled repeatedly over an Ii-day period; profiles of temperature, salinity and dissolved oxygen...... were concurrently recorded. Three replicate estimates of mortality were obtained for each pair of subsequent developmental stages from newly spawned eggs to early larvae. A consistent pattern of stage-specific mortality coincided well with previous experimental observations. Average daily mortality...... rates were 7.2% (eggs IA/IB), 38.7% (eggs (IB/II), 25.6% (eggs II/III), 40.0% (eggs III/IV), and 42.3% (eggs IV/early larvae). The cumulative mortality until hatch amounted to 99.9%. Results from hydrodynamic modelling, however, indicated that the drifter's trajectory was influenced by wind stress...

  14. Are antimicrobial defences in bird eggs related to climatic conditions associated with risk of trans-shell microbial infection?

    NARCIS (Netherlands)

    Horrocks, N.P.C.; Hine, K.; Hegemann, A.; Ndithia, H.K.; Shobrak, M.; Ostrowski, S.; Williams, J.B.; Matson, K.D.; Tieleman, B.I.

    2014-01-01

    Introduction All bird eggs are exposed to microbes in the environment, which if transmitted to the developing embryo, could cause hatching failure. However, the risk of trans-shell infection varies with environmental conditions and is higher for eggs laid in wetter environments. This might relate to

  15. Are antimicrobial defences in bird eggs related to climatic conditions associated with risk of trans-shell microbial infection?

    NARCIS (Netherlands)

    Horrocks, Nicholas P. C.; Hine, Kathryn; Hegemann, Arne; Ndithia, Henry K.; Shobrak, Mohammed; Ostrowski, Stephane; Williams, Joseph B.; Matson, Kevin D.; Tieleman, B. Irene

    2014-01-01

    Introduction: All bird eggs are exposed to microbes in the environment, which if transmitted to the developing embryo, could cause hatching failure. However, the risk of trans-shell infection varies with environmental conditions and is higher for eggs laid in wetter environments. This might relate

  16. Energy utilization and heat production of embryos from eggs originating from young and old broiler breeder flocks

    NARCIS (Netherlands)

    Nangsuay, A.; Meijerhof, R.; Ruangpanit, Y.; Kemp, B.; Brand, van den H.

    2013-01-01

    Two experiments were conducted to study the interaction between breeder age and egg size on the energy utilization (experiment 1) and heat production (experiment 2) of broiler embryos. In experiment 1, a total of 4,800 Ross-308 hatching eggs from 2 breeder ages (29 and 53 wk of age, or young and

  17. Transfer of spontaneously hatching or hatched blastocyst yields better pregnancy rates than expanded blastocyst transfer

    Directory of Open Access Journals (Sweden)

    Natachandra M Chimote

    2013-01-01

    Full Text Available Context: Blastocyst stage embryo transfer (ET has become routine practice in recent years. However, probably due to limitations of assisted hatching techniques, expanded blastocyst transfer (EBT is still the preferred mode. Inexplicably, not much consideration has been given to spontaneously hatching/hatched blastocyst transfer (SHBT. Aim: This study aimed to investigate developmental potential of spontaneously hatching/hatched blastocyst against EBT in in vitro fertilization (IVF cycles. Settings and Design: Prospective study of 146 women undergoing their first IVF- ET cycle. SUBJECTS AND Methods: On the basis of blastocyst status, women were classified into SHBT and EBT groups. Intracytoplasmic sperm injection cycles were excluded to remove male factor bias. Implantation rate (IR, clinical pregnancy rate, and live birth rate were the main outcome measures. Statistical Analysis: Graph-pad Prism 5 statistical package. Results: SHBT group showed significantly higher blastocyst formation rate (53.3 ± 17.5 vs. 43.1 ± 14.5%, P = 0.0098, top-quality blastocysts (71.8 vs. 53.7%, P = 0.0436, IR (43.6 vs. 27.9%, P = 0.0408, pregnancy rate (59.4 vs. 45.1%, P = 0.0173, and live birth rate (36.8 vs. 22.8%, P = 0.003 compared to EBT group. Multiple pregnancy rates remained comparable between the two groups. Implantation correlated strongly with top-quality blastocysts (Pearson, r = 0.4441 in SHBT group, while the correlation was nonsignificant in EBT group. Conclusion: Extending culture of expanded blastocysts by a few hours to allow transfer of spontaneously hatching/hatched blastocysts gives higher implantation and pregnancy rates with no added risk of multiple gestations. Spontaneously hatching/hatched blastocysts have a better potential to implant and develop into a positive pregnancy.

  18. The evolutionary position of nematodes

    Directory of Open Access Journals (Sweden)

    Gojobori Takashi

    2002-04-01

    Full Text Available Abstract Background The complete genomes of three animals have been sequenced by global research efforts: a nematode worm (Caenorhabditis elegans, an insect (Drosophila melanogaster, and a vertebrate (Homo sapiens. Remarkably, their relationships have yet to be clarified. The confusion concerns the enigmatic position of nematodes. Traditionally, nematodes have occupied a basal position, in part because they lack a true body cavity. However, the leading hypothesis now joins nematodes with arthropods in a molting clade, Ecdysozoa, based on data from several genes. Results We tested the Ecdysozoa hypothesis with analyses of more than 100 nuclear protein alignments, under conditions that would expose biases, and found that it was not supported. Instead, we found significant support for the traditional hypothesis, Coelomata. Our result is robust to different rates of sequence change among genes and lineages, different numbers of taxa, and different species of nematodes. Conclusion We conclude that insects (arthropods are genetically and evolutionarily closer to humans than to nematode worms.

  19. A rapid, sensitive and cost-efficient assay to estimate viability of potato cyst nematodes

    NARCIS (Netherlands)

    Elsen, van den S.J.J.; Ave, M.; Schoenmakers, N.; Landeweert, R.; Bakker, J.; Helder, J.

    2012-01-01

    Potato cyst nematodes (PCN) are quarantine organisms, and they belong to the economically most relevant pathogens of potato worldwide. Methodologies to assess the viability of their cysts which can contain 200-500 eggs protected by the hardened cuticle of a dead female, are either time and labor

  20. Analysis and Characterization of Vitamin B Biosynthesis Pathways in the Phytoparasitic Nematode Heterodera Glycines

    Science.gov (United States)

    Craig, James P.

    2009-01-01

    The soybean cyst nematode (SCN), "Heterodera glycines" is an obligate plant parasite that can cause devastating crop losses. To aide in the study of this pathogen, the SCN genome and the transcriptome of second stage juveniles and eggs were shotgun sequenced. A bioinformatic screen of the data revealed nine genes involved in the "de novo"…

  1. First report of the root-knot nematode Meloidogyne marylandi on Turfgrasses in Israel

    NARCIS (Netherlands)

    Oka, Y.; Karssen, G.; Mor, M.

    2004-01-01

    In a turfgrass nursery in Arava, Israel, a population of root-knot nematodes was isolated from poorly growing Zoysiagrass (Zoysia japonica Steud.) with symptoms of foliar chlorosis and roots with very small, smooth galls and protruding egg masses. The isolated population (genus Meloidogyne) included

  2. Hatching time and alevin growth prior to the onset of exogenous feeding in farmed, wild and hybrid Norwegian Atlantic salmon.

    Directory of Open Access Journals (Sweden)

    Monica Favnebøe Solberg

    Full Text Available The onset of exogenous feeding, when juveniles emerge from the gravel, is a critical event for salmonids where early emergence and large size provide a competitive advantage in the wild. Studying 131 farmed, hybrid and wild Norwegian Atlantic salmon families, originating from four wild populations and two commercial strains, we investigated whether approximately 10 generations of selection for faster growth has also resulted in increased somatic growth prior to the onset of exogenous feeding. In addition, we tested whether relaxed selection in farms has allowed for alterations in hatching time between farmed and wild salmon. Across three cohorts, wild salmon families hatched earlier than farmed salmon families, while hybrid families displayed intermediate hatching times. While the observed differences were small, i.e., 1-15 degree-days (0-3 days, as water temperatures were c. 5-6°C, these data suggest additive genetic variation for hatching time. Alevin length prior to exogenous feeding was positively related to egg size. After removal of egg size effects, no systematic differences in alevin length were observed between the wild and farmed salmon families. While these results indicate additive genetic variation for egg development timing, and wild salmon families consistently hatched earlier than farmed salmon families, these differences were so small they are unlikely to significantly influence early life history competition of farmed and wild salmon in the natural environment. This is especially the case given that the timing of spawning among females can vary by several weeks in some rivers. The general lack of difference in size between farmed and wild alevins, strongly suggest that the documented differences in somatic growth rate between wild and farmed Norwegian Atlantic salmon under hatchery conditions are first detectable after the onset of exogenous feeding.

  3. Trans-shell infection by pathogenic micro-organisms reduces the shelf life of non-incubated bird's eggs: a constraint on the onset of incubation?

    OpenAIRE

    Cook, Mark I; Beissinger, Steven R; Toranzos, Gary A; Rodriguez, Roberto A; Arendt, Wayne J

    2003-01-01

    Many birds initiate incubation before clutch completion, which results in asynchronous hatching. The ensuing within-brood size disparity often places later-hatched nestlings at a developmental disadvantage, but the functional significance of the timing of the onset of incubation is poorly understood. Early incubation may serve to maintain the viability of early-laid eggs, which declines over time owing to the putative effects of ambient temperature. An unexplored risk to egg viability is tran...

  4. Effects of in ovo injection of organic trace minerals and post-hatch holding time on broiler performance and bone characteristics

    Science.gov (United States)

    Effects of the in ovo injection of organic Mn, Zn, and Cu in association with post-hatch (POH) feed and water restriction on the performance and physical-chemical bone parameters of male Ross × Ross 708 broilers were examined. On 17 d of incubation, a total of 1,872 eggs were subjected to in ovo inj...

  5. Resistance and Resistant Reaction of Gossypium arboreum to the Reniform, Nematode, Rotylenchulus reniformis

    Science.gov (United States)

    Carter, William W.

    1981-01-01

    Gossypium arboreum 'Nanking CB 1402' possessed a high level of resistance to Rotylenchulus reniformis. Within 16 h, the nematode penetrated roots of resistant and susceptible cottons equally. After 36 h, significantly fewer nematodes were found in resistant roots. Larvae fed in either an endodermal or pericyclic cell and had no specificity for root tissue of a particular age. In roots of resistant G. arboreum '1402,' wall breakdown of pericyclic cells was evident after 3 d, endodermal and cortical cells collapsed, and the hypertrophied pericyclic cells disintegrated within 12 d. Cell walls immediately adjacent to the nematode's head were thickened and more safranin positive in resistant than in susceptible cotton cultivars. Several other cultivars of G. arboreum were also resistant to R. reniformis, based on nematode fecundity and percent egg reduction. PMID:19300777

  6. Efficacy of an energy block containing Duddingtonia flagrans in the control of gastrointestinal nematodes of sheep.

    Science.gov (United States)

    Sagüés, María F; Fusé, Luis A; Fernández, Alicia S; Iglesias, Lucía E; Moreno, Fabiana C; Saumell, Carlos A

    2011-09-01

    The efficacy of the nematode-trapping fungus Duddingtonia flagrans incorporated into an energy block was evaluated for the control of gastrointestinal nematodes in sheep. Four naturally parasitised sheep with average nematode egg counts of 2,470 eggs per gram grazed by pairs on two similar parasite-free paddocks for 30 days. During that period, one pair of sheep (treated animals, T1) received an energy block containing chlamydospores of D. flagrans at a dose of 200,000 chlamydopores/kg bw/day, while the second pair (control animals, C1) received a fungus-free energy block. The animals in both groups were taken off the paddocks after contaminating the pastures for a month with either nematode eggs plus fungal chlamydospores (T1) or nematode eggs alone (C1). Twelve parasite-free sheep were divided into two groups of six animals each, the treated group (T2) was placed on the paddock previously contaminated with parasites and fungus, while the control group (C2) was placed on the parasite-only paddock. These two groups grazed on their respective paddocks during 30 days and were then housed for 15 days, after which period they were slaughtered in order to determine the parasite burden present in each animal. Results showed that animals in group T2 harboured significantly less nematodes than their counterpart in group C2. The efficacy of D. flagrans was 92% against the total parasite burden, 100% against Haemonchus contortus and Teladorsagia circumcincta, 89.9% against Trichostrongylus colubriformis, 87.5% against Cooperia onchopora, and 90% against Trichostrongylus axei. No efficacy was detected against Nematodirus spathiger, Trichuris ovis and T. skrjabini.

  7. The effect of some aspects of low temperature and radiation on the survival of Latheticus orizae eggs

    International Nuclear Information System (INIS)

    Abdul Matin, A.S.M.

    1976-01-01

    In an attempt to delay hatching without affecting their viability, the eggs of Latheticus oryzae W. were subjected to cold treatment at 5deg for varying periods and at different stages of their development. A small dose of 0.5 krad of gamma radiation was also given at each of those temperature treatments. Most of the eggs hatched at 30deg following low-temperature ex-posures of 1 and 2 days. There was a significant decrease in hatch as the exposure period increased further (P<0.05). An egg exposure to 5deg also led to an increase in egg period and the increase was nearly equal to the period of cold exposure. Radiation did not alter the situation

  8. Egg quality traits and predictors of embryo and fry viability in red snapper Lutjanus campechanus

    Directory of Open Access Journals (Sweden)

    Agnès Bardon-Albaret

    2017-08-01

    Full Text Available The quality of red snapper eggs is highly variable and unpredictable in aquaculture, leading to high mortality during early larval rearing. In this work, the viability of red snapper eggs was monitored from fertilization until unfed larvae expired because of exhaustion of vitelline reserves to determine egg quality traits in this species. The spawns were obtained via strip spawning wild-caught females following hormonal induction with chorionic gonadotropin. Females were induced immediately after capture (wild group, n = 17 or held captive for the entire maturation period prior to induction (captive group, n = 7. Candidate predictors of egg quality measured on the female parent at the time of induction or on the spawn at ovulation were evaluated using correlation and multiple regression analysis. The fertilization rate, the hatching rate, and the duration of survival of unfed larvae post hatch were weakly correlated to each other (-0.23 < r < −0.08, revealing occurrence of distinct and independent components of egg quality. Spawns from captive females were characterized by a longer latency interval between hormonal induction and ovulation, lower fecundity, and lower hatching rates, as compared to those from wild females. Among the wild brood fish, a positive correlation was observed between the age of the female and the hatching rate. The best model optimized during stepwise multiple regression analysis of hatching rate data only explained 34% of the variance for this trait and no model could be optimized for the prediction of fertilization rate or the duration of survival post hatch. These results highlight the need to develop alternative egg quality measures to predict the viability of fry with confidence.

  9. Temperature during the last week of incubation. I. Effects on hatching pattern and broiler chicken embryonic organ development

    NARCIS (Netherlands)

    Maatjens, C.M.; Roovert-Reijrink, van I.A.M.; Engel, B.; Pol, van der C.W.; Kemp, B.; Brand, van den H.

    2016-01-01

    We investigated the effects of an eggshell temperature (EST) of 35.6, 36.7, 37.8, and 38.9°C applied from d of incubation (E) 15, E17, and E19 on hatching pattern and embryonic organ development. A total of 2,850 first-grade eggs of a 43-week-old Ross 308 broiler breeder flock were incubated at an

  10. Eggs viability of Aedes aegypti Linnaeus (Diptera, Culicidae under different environmental and storage conditions in Manaus, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    V. C. Soares-Pinheiro

    Full Text Available Abstract The viability of Aedes aegypti eggs was assessed in the Amazon region. The eggs were maintained under different conditions: indoors (insectarium and outdoors (natural environment, as well as in different storage types (plastic cup, paper envelope, plastic bag for different days. Egg viability was measured as the mean of hatchings observed from egg-bearing sheets of filter paper immersed in water, using three sheets randomly selected from each storage type and at both sites. There were significant differences in the viability of Ae. aegypti eggs with respect to the location (F=30.40; DF=1; P<0.0001, storage type (F=17.66; DF=2; P<0.0001, and time of storage (F=49.56; DF=9; P<0.0001. The interaction between storage site versus storage type was also significant (F=15.96; DF=2; P<0.0001. A higher hatching mean was observed for the eggs kept in the insectarium than for those outdoors (32.38 versus 7.46. Hatching rates of egg batches stored for 12 to 61 days ranged between 84 and 90%. A reduction was observed between 89 and 118 days, with values of 63 and 48%, respectively. With respect to type of storage, mean egg hatching was higher for the eggs in plastic cups (44.46. It was concluded that the viability of the eggs of Ae. aegypti in the Amazon region remains high up to 4 months, after which it declines drastically, although in this study hatching occurred for up to 8 months in very low percentages.

  11. Dipping of Eggs, Use of Low Temperature and Aeration to Improve Fruit Fly Bactrocera Carambolae (Drew and Hancock) Mass Rearing in Sterile Insect Technique Programme

    International Nuclear Information System (INIS)

    Nasution, Indah Arastuti; Achmad Nasroh Kuswadi

    2004-01-01

    In the Sterile Insect Technique (SIT) programme a large number of homogenous age of pupae should be produced to be sterilized and released into the field. A methodology to preserve eggs which at the same time delay the egg hatch is needed in the production of a large number of pupae with homogenous age. The study on method of preserving fruit fly eggs the effect of dipping, low temperature, on the viability of eggs, the quality of larvae hatched from the eggs, and the quality of pupae produced were observed. Viability of eggs were observed as percent of egg hatch, quality of larvae as number of pupae produced from 0.5 ml of eggs when reared on artificial diet, and quality of pupae as percent of the flies number emerged and flew from the pupae. In room temperature (26 o C) dipping did not preserve fruit fly eggs and aeration did not improve the preservation. Although after one day dipping the viability of eggs only decreased from 90 % (control) to 80.5 %, (without aeration) and 81.5 % (with aeration) it decreased the number of pupae been produced from 1447 pupae (control) to 382 pupae (without aeration) and 616 pupae (with aeration). Low temperature successfully preserved the egg up to 24 hours. After 24 hour dipping in low temperature (16 o C) the viability of eggs were decreased up to 84.75 % (without aeration) and able to produce 1104 pupae. Aeration during dipping in low temperature did not improve the preservation. (author)

  12. Development, Hatching, and Intestinal Establishment of Trichuris suis, - in vivo and in vitro Studies

    DEFF Research Database (Denmark)

    Vejzagic, Nermina

    Trichuris suis, the pig whipworm is a nematode parasite located in the large intestine of pigs. Embryonated eggs of T. suis (T. suis ova = TSO) constitute the active pharmaceutical ingredient (API) in a new medicinal product, which is currently tested in human clinical trials as a potential treat...

  13. 7 CFR 1250.306 - Commercial eggs or eggs.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Commercial eggs or eggs. 1250.306 Section 1250.306... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE EGG RESEARCH AND PROMOTION Egg Research and Promotion Order Definitions § 1250.306 Commercial eggs or eggs. Commercial eggs or eggs means...

  14. Comparison between morphological and staining characteristics of live and dead eggs of Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    AK Sarvel

    2006-10-01

    Full Text Available Schistosoma mansoni eggs are classified, according to morphological characteristics, as follows: viable mature and immature eggs; dead mature and immature eggs, shells and granulomas. The scope of this study was to compare the staining characteristics of different morphological types of eggs in the presence of fluorescent labels and vital dyes, aiming at differentiating live and dead eggs. The eggs were obtained from the intestines of infected mice, and put into saline 0.85%. The fluorescent labels were Hoechst 33258 and Acridine Orange + Ethidium Bromide and vital dyes (Trypan Blue 0.4% and Neutral Red 1%. When labelled with the probe Hoechst 33258, some immature eggs, morphologically considered viable, presented fluorescence (a staining characteristic detected only in dead eggs; mature eggs did not present fluorescence, and the other types of dead eggs, morphologically defined, showed fluorescence. As far as Acridine Orange + Ethidium Bromide are concerned, either the eggs considered to be live, or the dead ones, presented staining with green color, and only the hatched and motionless miracidium was stained with an orange color. Trypan Blue was not able to stain the eggs, considered to be dead but only dead miracidia which had emerged out of the shell. Neutral Red stained both live and dead eggs. Only the fluorescent Hoechst 33258 can be considered a useful tool for differentiation between dead and live eggs.

  15. Efficacy and toxicity of iodine disinfection of Atlantic salmon eggs

    Science.gov (United States)

    Chalupnicki, M.A.; Ketola, H.G.; Starliper, C.E.; Gallagher, D.

    2011-01-01

    Recent interest in the restoration of Atlantic salmon Salmo salar in the Great Lakes has given rise to new culture techniques and management programs designed to reduce pathogen transmission while stabilizing and enhancing wild populations. We examined the toxicity of iodine to Atlantic salmon eggs and its effectiveness as a disinfectant against bacteria on egg surfaces. We spawned and fertilized eight gravid Atlantic salmon from Cayuga Lake, New York, and exposed their eggs to 10 concentrations of iodine (5, 10, 50, 75, 100, 500, 750, 1,000, 5,000, and 7,500 mg/L) for 30 min during water hardening. An additional subsample of unfertilized eggs was also exposed to some of the same concentrations of iodine (5, 10, 50, 75, and 100 mg/L) to determine the efficiency of disinfection. Viable eggs were only obtained from four females. Survival of eggs to the eyed stage and hatch tended to be reduced at iodine concentrations of 50 and 75 mg/L and was significantly reduced at concentrations of 100 mg/L iodine or more. We calculated the concentrations of iodine that killed 50% of the Atlantic salmon eggs at eye-up and hatch to be 175 and 85 mg/L, respectively. Aeromonas veronii, A. schubertii, A. hydrophila, A. caviae, Plesiomonas shiggeloides, and Citrobacter spp. were the predominant bacteria present on the surface of green eggs and were significantly reduced by an iodine immersion. The use of iodine as a disinfectant on Atlantic salmon eggs was effective at low concentrations (50–75 mg/L), for which toxicity to Atlantic salmon was minimal.

  16. Consequences of Hatch Phenology on Stages of Fish Recruitment.

    Directory of Open Access Journals (Sweden)

    David M Bogner

    Full Text Available Little is known about how hatch phenology (e.g., the start, peak, and duration of hatching could influence subsequent recruitment of freshwater fishes into a population. We used two commonly sympatric fish species that exhibit different hatching phenologies to examine recruitment across multiple life stages. Nine yellow perch (Perca flavescens and bluegill (Lepomis macrochirus annual cohorts were sampled from 2004 through 2013 across larval, age-0, age-1, and age-2 life stages in a Nebraska (U.S.A. Sandhill lake. Yellow perch hatched earlier in the season and displayed a more truncated hatch duration compared to bluegill. The timing of hatch influenced recruitment dynamics for both species but important hatching metrics were not similar between species across life stages. A longer hatch duration resulted in greater larval yellow perch abundance but greater age-1 bluegill abundance. In contrast, bluegill larval and age-0 abundances were greater during years when hatching duration was shorter and commenced earlier, whereas age-0 yellow perch abundance was greater when hatching occurred earlier. As a result of hatch phenology, yellow perch recruitment variability was minimized sooner (age-0 life stage than bluegill (age-1 life stage. Collectively, hatch phenology influenced recruitment dynamics across multiple life stages but was unique for each species. Understanding the complexities of when progeny enter an environment and how this influences eventual recruitment into a population will be critical in the face of ongoing climate change.

  17. Uptake and elimination of aromatic hydrocarbons a chlorinated biphenyl in eggs and larvae of cod Gadus morhua

    OpenAIRE

    Solbakken, Jan Erik; Tilseth, Snorre; Palmork, Karsten H.

    1984-01-01

    Artificially fertilized eggs and newly hatched larvae of cod Gadus rnorhua L. were exposed to 14C labelled naphthalene, phenanthrene, benzo(a)pyrene and 2. 4. 5. 2', 4', 5'-hexachlorobiphenyl (PCB) for 24 h and thereafter transferred to clean seawater. Radioactivity in eggs and larvae was measured at different times during exposure and after transfer to clean seawater. Maximum accumulation was found with phenanthrene, whereas naphthalene accumulated only slightly in both eggs a...

  18. A rapid, sensitive, and cost-efficient assay to estimate viability of potato cyst nematodes.

    Science.gov (United States)

    van den Elsen, Sven; Ave, Maaike; Schoenmakers, Niels; Landeweert, Renske; Bakker, Jaap; Helder, Johannes

    2012-02-01

    Potato cyst nematodes (PCNs) are quarantine organisms, and they belong to the economically most relevant pathogens of potato worldwide. Methodologies to assess the viability of their cysts, which can contain 200 to 500 eggs protected by the hardened cuticle of a dead female, are either time and labor intensive or lack robustness. We present a robust and cost-efficient viability assay based on loss of membrane integrity upon death. This assay uses trehalose, a disaccharide present at a high concentration in the perivitelline fluid of PCN eggs, as a viability marker. Although this assay can detect a single viable egg, the limit of detection for regular field samples was higher, ≈10 viable eggs, due to background signals produced by other soil components. On the basis of 30 nonviable PCN samples from The Netherlands, a threshold level was defined (ΔA(trehalose) = 0.0094) below which the presence of >10 viable eggs is highly unlikely (true for ≈99.7% of the observations). This assay can easily be combined with a subsequent DNA-based species determination. The presence of trehalose is a general phenomenon among cyst nematodes; therefore, this method can probably be used for (for example) soybean, sugar beet, and cereal cyst nematodes as well.

  19. Amphibian embryo and parental defenses and a larval predator reduce egg mortality from water mold.

    Science.gov (United States)

    Gomez-Mestre, Ivan; Touchon, Justin C; Warkentin, Karen M

    2006-10-01

    Water molds attack aquatic eggs worldwide and have been associated with major mortality events in some cases, but typically only in association with additional stressors. We combined field observations and laboratory experiments to study egg stage defenses against pathogenic water mold in three temperate amphibians. Spotted salamanders (Ambystoma maculatum) wrap their eggs in a protective jelly layer that prevents mold from reaching the embryos. Wood frog (Rana sylvatica) egg masses have less jelly but are laid while ponds are still cold and mold growth is slow. American toad (Bufo americanus) eggs experience the highest infection levels. They are surrounded by thin jelly and are laid when ponds have warmed and mold grows rapidly. Eggs of all three species hatched early when infected, yielding smaller and less developed hatchlings. This response was strongest in B. americanus. Precocious hatching increased vulnerability of wood frog hatchlings to invertebrate predators. Finally, despite being potential toad hatchling predators, R. sylvatica tadpoles can have a positive effect on B. americanus eggs. They eat water mold off infected toad clutches, increasing their hatching success.

  20. Toxicity of methylmercury injected into eggs when dissolved in water versus corn oil

    Science.gov (United States)

    Heinz, G.H.; Hoffman, D.J.; Klimstra, J.D.; Stebbins, K.R.; Kondrad, S.L.

    2011-01-01

    In a previous study, the embryotoxicity of methylmercury dissolved in corn oil was compared among 26 species of birds. Corn oil is not soluble in the water-based matrix that constitutes the albumen of an egg. To determine whether the use of corn oil limited the usefulness of this earlier study, a comparison was made of the embryotoxicity of methylmercury dissolved in corn oil versus water. Mallard (Anas platyrhynchos) and chicken (Gallus gallus) eggs were injected with methylmercury chloride dissolved in corn oil or water to achieve concentrations of 0, 0.2, 0.4, 0.8, and 1.6??g/g mercury in the egg on a wet weight basis. Hatching success at each dose of mercury was compared between the two solvents. For mallards, 16.4% of the eggs injected with 1.6??g/g mercury dissolved in water hatched, which was statistically lower than the 37.6% hatch rate of eggs injected with 1.6??g/g mercury dissolved in corn oil, but no differences in hatching success were observed between corn oil and water at any of the other doses. With chicken eggs, no significant differences occurred in percentage hatch of eggs between corn oil and water at any of the mercury doses. Methylmercury dissolved in corn oil seems to have a toxicity to avian embryos similar to that of does methylmercury dissolved in water. Consequently, the results from the earlier study that described the toxicity of methylmercury dissolved in corn oil to avian embryos were probably not compromised by the use of corn oil as a solvent. ?? 2011 SETAC.

  1. Factors affecting the toxicity of methylmercury injected into eggs

    Science.gov (United States)

    Heinz, G.H.; Hoffman, D.J.; Kondrad, S.L.; Erwin, C.A.

    2006-01-01

    . In addition, some species of bird eggs require incubation on their sides with the eggs being rolled 180? for them to develop normally. Therefore, we adopted a procedure of incubating the eggs of all species on their sides and rolling them 180? every hour. Little has been published about the conditions of temperature, humidity, and the movements to which eggs of wild birds need to be subjected for them to hatch optimally under artificial incubation. Not unexpectedly, hatching success in an artificial incubator is generally less than what natural incubation by the parents can achieve. However, the survival of control embryos of most wild bird species was good (generally > 80%) up to within 1 or 2 days of hatching when we incubated the eggs at 37.5?C (or 37.6?C for gallinaceous species) at a relative humidity that resulted in an approximate 15% to 16% loss in egg weight by the end of incubation and by incubating the eggs on their sides and rolling them 180?/h. To improve statistical comparisons, we used survival through 90% of incubation as our measurement to compare survival of controls with survival of eggs injected with graded concentrations of mercury.

  2. Do Acartia tonsa (Dana) eggs regulate their volume and osmolality as salinity changes?

    DEFF Research Database (Denmark)

    Hansen, Benni Winding; Drillet, Guillaume; Pedersen, Morten Foldager

    2012-01-01

    Subitaneous eggs from an euryhaline calanoid copepod Acartia tonsa were challenged by changes in salinity within the range from full strength salinity, down to zero and up to >70 psu. Egg volume changed immediately, increasing from 2.8 × 105 μm3 at full strength salinity (35 psu) to 3.8 × 105 μm3...... at 0 psu and back to its initial volume when gradually being returned to full strength salinity. Egg osmolality followed the molality of the surrounding water when challenged within a salinity range from 2 to 50 psu. Egg respiration was not affected when eggs kept at 35 psu was exposed to low salinity...... (2 psu). These results suggest that eggs are unable to regulate their volume or osmolality when challenged with changes in salinity. Gradual changes in salinity from 35 to 2 psu and back did not harm the eggs (embryos), since the hatching success remained unaffected by such changes in salinity...

  3. Protein profiles of hatchery egg shell membrane.

    Science.gov (United States)

    Rath, N C; Liyanage, R; Makkar, S K; Lay, J O

    2016-01-01

    Eggshells which consist largely of calcareous outer shell and shell membranes, constitute a significant part of poultry hatchery waste. The shell membranes (ESM) not only contain proteins that originate from egg whites but also from the developing embryos and different contaminants of microbial and environmental origins. As feed supplements, during post hatch growth, the hatchery egg shell membranes (HESM) have shown potential for imparting resistance of chickens to endotoxin stress and exert positive health effects. Considering that these effects are mediated by the bioactive proteins and peptides present in the membrane, the objective of the study was to identify the protein profiles of hatchery eggshell membranes (HESM). Hatchery egg shell membranes were extracted with acidified methanol and a guanidine hydrochloride buffer then subjected to reduction/alkylation, and trypsin digestion. The methanol extract was additionally analyzed by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). The tryptic digests were analyzed by liquid chromatography and tandem mass spectrometry (LC-MS-MS) to identify the proteins. Our results showed the presence of several proteins that are inherent and abundant in egg white such as, ovalbumin, ovotransferrin, ovocleidin-116, and lysozyme, and several proteins associated with cytoskeletal, cell signaling, antimicrobial, and catalytic functions involving carbohydrate, nucleic acid, and protein metabolisms. There were some blood derived proteins most likely originating from the embryos and several other proteins identified with different aerobic, anaerobic, gram positive, gram negative, soil, and marine bacterial species some commensals and others zoonotic. The variety of bioactive proteins, particularly the cell signaling and enzymatic proteins along with the diverse microbial proteins, make the HESM suitable for nutritional and biological application to improve post hatch immunity of poultry.

  4. Egg weight and gamma-rays effects. Pt. 1

    International Nuclear Information System (INIS)

    Shebaita, M.K.; Ezzat, I.E.; Kamar, G.A.R.

    1979-01-01

    Two groups of egg weight from Egyptian Fayoumi breed were used in this study. The first group ranged in weight from 36-43 grams (group A) and the second group ranged from 44-50 grams (group B). Each egg weight group was divided to 6 exposure treatments to 60 Co gamma rays (non-irradiated, 150 rads, 300 rads, 450 rads, 600 rads and 750 rads). The data showed that embryonic mortality was 75% higher in irradiated treatments compared with the non-irradiated, and 50% of the mortality occurred during the first 5 days after the exposure. Moreover, mortality was 18% higher in group A than in group B. However, the abnormality was 6.4% in group A and 10.8% in group B. A delay in hatching time was observed and the hatching percent decreased due to the exposure to gamma rays. The relationship between hatching % (Y) and the dose level (X) was Y = 86.6 esup(-0.00041x) in group A and Y = 85.5 esup(-0.00028x) in group B. On the other hand, the hatching weight in irradiated treatments was higher (P [de

  5. Learning hatching for pen-and-ink illustration of surfaces

    KAUST Repository

    Kalogerakis, Evangelos

    2012-01-01

    This article presents an algorithm for learning hatching styles from line drawings. An artist draws a single hatching illustration of a 3D object. Her strokes are analyzed to extract the following per-pixel properties: hatching level (hatching, cross-hatching, or no strokes), stroke orientation, spacing, intensity, length, and thickness. A mapping is learned from input geometric, contextual, and shading features of the 3D object to these hatching properties, using classification, regression, and clustering techniques. Then, a new illustration can be generated in the artist\\'s style, as follows. First, given a new view of a 3D object, the learned mapping is applied to synthesize target stroke properties for each pixel. A new illustration is then generated by synthesizing hatching strokes according to the target properties. © 2012 ACM.

  6. Disruption of prefoldin-2 protein synthesis in root-knot nematodes via host-mediated gene silencing efficiently reduces nematode numbers and thus protects plants.

    Science.gov (United States)

    Ajjappala, Hemavathi; Chung, Ha Young; Sim, Joon-Soo; Choi, Inchan; Hahn, Bum-Soo

    2015-03-01

    The aim of this study is to demonstrate the feasibility of down-regulating endogeneous prefoldin-2 root-knot nematode transcripts by expressing dsRNA with sequence identity to the nematode gene in tobacco roots under the influence of strong Arabidopsis ubiquitin (UBQ1) promoter. Root-knot nematodes (RKNs) are sedentary endoparasites infecting a wide range of plant species. They parasitise the root system, thereby disrupting water and nutrient uptake and causing major reductions in crop yields. The most reliable means of controlling RKNs is via the use of soil fumigants such as methyl bromide. With the emergence of RNA interference (RNAi) technology, which permits host-mediated nematode gene silencing, a new strategy to control plant pathogens has become available. In the present study, we investigated host-induced RNAi gene silencing of prefoldin-2 in transgenic Nicotiana benthamiana. Reductions in prefoldin-2 mRNA transcript levels were observed when nematodes were soaked in a dsRNA solution in vitro. Furthermore, nematode reproduction was suppressed in RNAi transgenic lines, as evident by reductions in the numbers of root knots (by 34-60 % in independent RNAi lines) and egg masses (by 33-58 %). Endogenous expression of prefoldin-2, analysed via real-time polymerase chain reaction and Western blotting, revealed that the gene was strongly expressed in the pre-parasitic J2 stage. Our observations demonstrate the relevance and potential importance of targeting the prefoldin gene during the nematode life cycle. The work also suggests that further improvements in silencing efficiency in economically important crops can be accomplished using RNAi directed against plant-parasitic nematodes.

  7. Effects of host nutrition on virulence and fitness of entomopathogenic nematodes: Lipid- and protein-based supplements in Tenebrio molitor diets

    Science.gov (United States)

    Shapiro-Ilan, David; Rojas, M. Guadalupe; Morales-Ramos, Juan A.; Lewis, Edwin E.; Tedders, W. Louis

    2008-01-01

    Entomopathogenic nematodes, Heterorhabditis indica and Steinernema riobrave, were tested for virulence and reproductive yield in Tenebrio molitor that were fed wheat bran diets with varying lipid- and protein-based supplements. Lipid supplements were based on 20% canola oil, peanut, pork or salmon, or a low lipid control (5% canola). Protein treatments consisted of basic supplement ingredients plus 0, 10, or 20% egg white; a bran-only control was also included. Some diet supplements had positive effects on nematode quality, whereas others had negative or neutral effects. All supplements with 20% lipids except canola oil caused increased T. molitor susceptibility to H. indica, whereas susceptibility to S. riobrave was not affected. Protein supplements did not affect host susceptibility, and neither lipid nor protein diet supplements affected reproductive capacity of either nematode species. Subsequently, we determined the pest control efficacy of progeny of nematodes that had been reared through T. molitor from different diets against Diaprepes abbreviatus and Otiorhynchus sulcatus. All nematode treatments reduced insect survival relative to the control (water only). Nematodes originating from T. molitor diets with the 0% or 20% protein exhibited lower efficacy versus D. abbreviatus than the intermediate level of protein (10%) or bran-only treatments. Nematodes originating from T. molitor lipid or control diets did not differ in virulence. Our research indicates that nutritional content of an insect host diet can affect host susceptibility to entomopathogenic nematodes and nematode fitness; therefore, host media could conceivably be optimized to increase in vivo nematode production efficiency. PMID:19259513

  8. Effect Of Pyridoxine Injection In Japanese Quail Eggs On HATCHABILITY, Performance And Some Physiological Parameters

    International Nuclear Information System (INIS)

    ELSAYED, M.A.; WAKWAK, M.M.; MAHROSE, KH.M.

    2010-01-01

    The present study was carried out at the poultry farm found in the Nuclear Research Center, Atomic Energy Authority, Inshas, Sharkia Governorate, Egypt, during January 2009. A total number of two hundreds and seventy five quail eggs were used in an experiment of a completely randomized design to estimate hatchability percentage, chick weight at hatch, growth performance, some blood parameters and carcass traits of Japanese quails as affected by injecting their eggs with pyridoxine. Eggs were divided into 5 groups (55 eggs each); the first group (without injection) was served as control while the second group was injected in the width end of the egg with 500 μl saline. The third, fourth and fifth groups were injected in the width end of the Japanese quail eggs with 40, 80 and 120 μg pyridoxine, respectively, dissolved in 500 μl saline. Hatchability percentage, live body weight, daily body weight gain and some organ weights (liver, gizzard and heart) were studied. At the end of the experiment, blood samples were collected for analyses. It was observed that the groups of quail eggs received 120 μg pyridoxine injection recorded the highest hatchability percent. Chick weight at hatch was non-significantly affected by saline solution injection. The birds hatched from the groups of quail eggs received 120μg pyridoxine recorded the highest live body weight, especially during the 2 nd and 3 rd weeks of age. The daily body weight gain was significantly affected by pyridoxine injection only during the intervals of 1 to 2, 3 to 4 and from 1 to 6 weeks of age. Serum total protein, albumin and globulin concentrations were highly significantly elevated in the birds hatched from the groups of quail eggs received 120μg pyridoxine than other groups. Serum AST activity was highly significantly increased in the birds hatched from the groups of quail eggs received 40 μg pyridoxine than other groups while serum ALT activity and calcium concentration were non

  9. Ovicidal activity of acrolein vapors to Indian meal moth eggs of various ages.

    Science.gov (United States)

    Pourmirza, Ali Asghr

    2007-09-01

    The effect of acrolein vapors against carefully aged eggs of Indian meal moth at 27 +/- 1 and 17 +/- 1 degrees C at different dosage levels of acrolein over various exposure times was determined. Considerable variation in the susceptibility of different age groups of eggs was apparent in the fiducial limits of the LD50 values. At both temperatures and 24 h exposure period, eggs aged 1-2 day-old were more tolerant to acrolein than other age groups. In all bioassays, eggs exposed to higher dosages of acrolein developed at smaller rate. This was significant for the eggs, which were exposed to the highest dosage for 24 h. Increasing the temperature from 17 +/- 1 to 27 +/- 1 degrees C greatly increased the efficacy of acrolein. Overall, at 27 +/- 1 degrees C eggs of P. interpunctella were killed by less than one-fourth of the dosage required for control at 17 +/- 1 degrees C. Acrolein achieved 50% mortality with a dosage of 3.80 mg L(-1) in 1-2 day-old eggs at 27 +/- 1 degrees C. At this temperature hatching was retarded and greatly reduced when eggs aged 1-2 day-old were exposed to 32 mg L(-1) of acrolein for the 24 h exposure period. There was no evidence of a hatch delay longer than the time spent under vapors for eggs exposed at 17 +/- 1 or 27 +/- 1 degrees C, indicating that some development must have occurred under fumigation.

  10. Productive Performance of Broiler after Pre and /or Post-hatching Injection of Thyroid and Growth Hormones

    International Nuclear Information System (INIS)

    Gamal, M.H.; El-Gendi, G.M.

    2003-01-01

    A total number of 1340 eggs from Arbor Acres parent breed were used in this study. Eggs were divided into two division according to the incubation relative humidity (48% and 52%). Eggs of each division were than subdivided into ten groups, eggs of 1 st , 2 nd and 3 rd groups were injected with 0.05, 0.10 and 0.15μg eltroxin, respectively, those of the 4 th , 5 th and 6 th groups were injected with 0.05, 0.10 and 0.15 mg Carbimazole, respectively, while eggs of the 7 th , 8 th and 9 th groups were injected with 0.005, 0.02 and 0.04 I.U. growth hormone, respectively. Eggs of the 10 th group were injected with distilled water and used as control group. Each group was divided into two divisions, eggs of the first division were injected just before incubation (into the air cell) and those of the second division were injected at the 9 th day of incubation period (into the embryonic allantoic cavity). A total number of 960 hatched chicks were randomly selected (24 chicks of cach group), wing banded, individually weighted, vaccinated and standard conditions of management, environment, hygiene and nutrition

  11. Snapping turtles (Chelydra serpentina) as bioindicators in Canadian Areas of Concern in the Great Lakes Basin. II. Changes in hatching success and hatchling deformities in relation to persistent organic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Solla, S.R. de , [Population Assessment Unit, Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Box 5050, Burlington, ON, L7R 4A6 (Canada); Fernie, K J; Ashpole, S [Population Assessment Unit, Canadian Wildlife Service, Environment Canada, 867 Lakeshore Road, Box 5050, Burlington, ON, L7R 4A6 (Canada)

    2008-06-15

    Hatching success and deformities in snapping turtle hatchlings (Chelydra serpentina) were evaluated using eggs collected from 14 sites in the Canadian lower Great Lakes, including Areas of Concern (AOC), between 2001 and 2004. Eggs were analyzed for PCBs, PBDEs, and pesticides. Between 2002 and 2004, hatchling deformity rates were highest in two AOCs (18.3-28.3%) compared to the reference sites (5.3-11.3%). Hatching success was poorest in three AOCs (71.3-73.1%) compared to the reference sites (86.0-92.7%). Hatching success and deformity rates were generally poorer in 2001 compared to 2002-2004, irrespective of the study location and could be due to egg handling stress in 2001. Hatching success and deformities were generally worst from the Wheatley Harbour, St. Lawrence River (Cornwall), Detroit River, and Hamilton Harbour AOCs. Associations between contaminant burdens with embryonic development were sufficiently poor that the biological relevance is questionable. Stressors not measured may have contributed to development abnormalities. - Hatching success and deformities of snapping turtle eggs varied among Great Lake Areas of Concern, but were not attributable to specific chemical exposure.

  12. Snapping turtles (Chelydra serpentina) as bioindicators in Canadian Areas of Concern in the Great Lakes Basin. II. Changes in hatching success and hatchling deformities in relation to persistent organic pollutants

    International Nuclear Information System (INIS)

    Solla, S.R. de; Fernie, K.J.; Ashpole, S.

    2008-01-01

    Hatching success and deformities in snapping turtle hatchlings (Chelydra serpentina) were evaluated using eggs collected from 14 sites in the Canadian lower Great Lakes, including Areas of Concern (AOC), between 2001 and 2004. Eggs were analyzed for PCBs, PBDEs, and pesticides. Between 2002 and 2004, hatchling deformity rates were highest in two AOCs (18.3-28.3%) compared to the reference sites (5.3-11.3%). Hatching success was poorest in three AOCs (71.3-73.1%) compared to the reference sites (86.0-92.7%). Hatching success and deformity rates were generally poorer in 2001 compared to 2002-2004, irrespective of the study location and could be due to egg handling stress in 2001. Hatching success and deformities were generally worst from the Wheatley Harbour, St. Lawrence River (Cornwall), Detroit River, and Hamilton Harbour AOCs. Associations between contaminant burdens with embryonic development were sufficiently poor that the biological relevance is questionable. Stressors not measured may have contributed to development abnormalities. - Hatching success and deformities of snapping turtle eggs varied among Great Lake Areas of Concern, but were not attributable to specific chemical exposure

  13. Development of a Fluvial Egg Drift Simulator to evaluate the transport and dispersion of Asian carp eggs in rivers

    Science.gov (United States)

    Garcia, Tatiana; Jackson, P. Ryan; Murphy, Elizabeth A.; Valocchi, Albert J.; Garcia, Marcelo H.

    2013-01-01

    Asian carp are migrating towards the Great Lakes and are threatening to invade this ecosystem, hence there is an immediate need to control their population. The transport of Asian carp eggs in potential spawning rivers is an important factor in its life history and recruitment success. An understanding of the transport, development, and fate of Asian carp eggs has the potential to create prevention, management, and control strategies before the eggs hatch and develop the ability to swim. However, there is not a clear understanding of the hydrodynamic conditions at which the eggs are transported and kept in suspension. This knowledge is imperative because of the current assumption that suspension is required for the eggs to survive. Herein, FluEgg (Fluvial Egg Drift Simulator), a three-dimensional Lagrangian model capable of evaluating the influence of flow velocity, shear dispersion and turbulent diffusion on the transport and dispersal patterns of Asian carp eggs is presented. The model's variables include not only biological behavior (growth rate, density changes) but also the physical characteristics of the flow field, such as mean velocities and eddy diffusivities. The performance of the FluEgg model was evaluated using observed data from published flume experiments conducted in China with water-hardened Asian carp eggs as subjects. FluEgg simulations show a good agreement with the experimental data. The model was also run with observed data from the Sandusky River in Ohio to provide a real-world demonstration case. This research will support the identification of critical hydrodynamic conditions (e.g., flow velocity, depth, and shear velocity) to maintain eggs in suspension, assist in the evaluation of suitable spawning rivers for Asian carp populations and facilitate the development of prevention, control and management strategies for Asian carp species in rivers and water bodies.

  14. Identification of the key weather factors affecting overwintering success of Apolygus lucorum eggs in dead host tree branches.

    Directory of Open Access Journals (Sweden)

    Hongsheng Pan

    Full Text Available Understanding the effects of weather on insect population dynamics is crucial to simulate and forecast pest outbreaks, which is becoming increasingly important with the effects of climate change. The mirid bug Apolygus lucorum is an important pest on cotton, fruit trees and other crops in China, and primarily lays its eggs on dead parts of tree branches in the fall for subsequent overwintering. As such, the eggs that hatch the following spring are most strongly affected by ambient weather factors, rather than by host plant biology. In this study, we investigated the effects of three major weather factors: temperature, relative humidity and rainfall, on the hatching rate of A. lucorum eggs overwintering on dead branches of Chinese date tree (Ziziphus jujuba. Under laboratory conditions, rainfall (simulated via soaking was necessary for the hatching of overwintering A. lucorum eggs. In the absence of rainfall (unsoaked branches, very few nymphs successfully emerged under any of the tested combinations of temperature and relative humidity. In contrast, following simulated rainfall, the hatching rate of the overwintering eggs increased dramatically. Hatching rate and developmental rate were positively correlated with relative humidity and temperature, respectively. Under field conditions, the abundance of nymphs derived from overwintering eggs was positively correlated with rainfall amount during the spring seasons of 2009-2013, while the same was not true for temperature and relative humidity. Overall, our findings indicate that rainfall is the most important factor affecting the hatching rate of overwintering A. lucorum eggs on dead plant parts and nymph population levels during the spring season. It provides the basic information for precisely forecasting the emergence of A. lucorum and subsequently timely managing its population in spring, which will make it possible to regional control of this insect pest widely occurring in multiple crops in

  15. Identification of the key weather factors affecting overwintering success of Apolygus lucorum eggs in dead host tree branches.

    Science.gov (United States)

    Pan, Hongsheng; Liu, Bing; Lu, Yanhui; Desneux, Nicolas

    2014-01-01

    Understanding the effects of weather on insect population dynamics is crucial to simulate and forecast pest outbreaks, which is becoming increasingly important with the effects of climate change. The mirid bug Apolygus lucorum is an important pest on cotton, fruit trees and other crops in China, and primarily lays its eggs on dead parts of tree branches in the fall for subsequent overwintering. As such, the eggs that hatch the following spring are most strongly affected by ambient weather factors, rather than by host plant biology. In this study, we investigated the effects of three major weather factors: temperature, relative humidity and rainfall, on the hatching rate of A. lucorum eggs overwintering on dead branches of Chinese date tree (Ziziphus jujuba). Under laboratory conditions, rainfall (simulated via soaking) was necessary for the hatching of overwintering A. lucorum eggs. In the absence of rainfall (unsoaked branches), very few nymphs successfully emerged under any of the tested combinations of temperature and relative humidity. In contrast, following simulated rainfall, the hatching rate of the overwintering eggs increased dramatically. Hatching rate and developmental rate were positively correlated with relative humidity and temperature, respectively. Under field conditions, the abundance of nymphs derived from overwintering eggs was positively correlated with rainfall amount during the spring seasons of 2009-2013, while the same was not true for temperature and relative humidity. Overall, our findings indicate that rainfall is the most important factor affecting the hatching rate of overwintering A. lucorum eggs on dead plant parts and nymph population levels during the spring season. It provides the basic information for precisely forecasting the emergence of A. lucorum and subsequently timely managing its population in spring, which will make it possible to regional control of this insect pest widely occurring in multiple crops in summer.

  16. ZZ HATCHES-18, Database for radiochemical modelling

    International Nuclear Information System (INIS)

    Heath, T.G.

    2008-01-01

    1 - Description of program or function: HATCHES is a referenced, quality assured, thermodynamic database, developed by Serco Assurance for Nirex. Although originally compiled for use in radiochemical modelling work, HATCHES also includes data suitable for many other applications e.g. toxic waste disposal, effluent treatment and chemical processing. It is used in conjunction with chemical and geochemical computer programs, to simulate a wide variety of reactions in aqueous environments. The database includes thermodynamic data (the log formation constant and the enthalpy of formation for the chemical species) for the actinides, fission products and decay products. The datasets for Ni, Tc, U, Np, Pu and Am are based on the NEA reviews of the chemical thermodynamics of these elements. The data sets for these elements with oxalate, citrate and EDTA are based on the NEA-selected values. For iso-saccharinic acid, additional data (non-selected values) have been included from the NEA review as well as data derived from other sources. HATCHES also includes data for many toxic metals and for elements commonly found in groundwaters or geological materials. HARPHRQ operates by reference to the PHREEQE master species list. Thus the thermodynamic information supplied is: a) the log equilibrium constant for the formation reaction of the requested species from the PHREEQE master species for the corresponding elements; b) the enthalpy of reaction for the formation reaction of the requested species from the PHREEQE master species for the corresponding elements. This version of HATCHES has been updated since the previous release to provide consistency with the selected data from two recent publications in the OECD Nuclear Energy Agency series on chemical thermodynamics: Chemical Thermodynamics Series Volume 7 (2005): Chemical Thermodynamics of Selenium by Aeke Olin (Chairman), Bengt Nolaeng, Lars-Olof Oehman, Evgeniy Osadchii and Erik Rosen and Chemical Thermodynamics Series Volume 8

  17. Molecular aspects of cyst nematodes.

    Science.gov (United States)

    Lilley, Catherine J; Atkinson, Howard J; Urwin, Peter E

    2005-11-01

    SUMMARY Taxonomy: Superkingdom Eukaryota; kingdom Metazoa; phylum Nematoda; class Chromadorea; order Tylenchida; suborder Tylenchina; superfamily Tylenchoidea; family Heteroderidae; subfamily Heteroderinae; main genera Heterodera and Globodera. Cyst nematodes comprise approximately 100 known species in six genera. They are pathogens of temperate, subtropical and tropical plant species and the host range of many species is narrow. The most economically important species are within the Globodera and Heterodera genera. Globodera pallida and G. rostochiensis are important pathogens of potato crops. There are many economic species in the Heterodera genus, including Heterodera glycines (soybean cyst nematode), H. avenae (cereal cyst nematode) and H. schachtii (sugar beet cyst nematode), the last of which attacks a range of Chenopodiaceae and Cruciferae, including Arabidopsis thaliana. Disease symptoms: Field symptoms of severe cyst nematode infection are often stunting, wilting and chlorosis, but considerable yield loss can occur without obvious symptoms. The only unique indicator of cyst nematode infection is the presence of adult female nematodes attached to host roots after several weeks of parasitism. Disease control: This is usually achieved by using integrated pest management involving cultural practices such as crop rotation, resistant cultivars if available and chemical control when economically justified.

  18. RNAi effector diversity in nematodes.

    Directory of Open Access Journals (Sweden)

    Johnathan J Dalzell

    2011-06-01

    Full Text Available While RNA interference (RNAi has been deployed to facilitate gene function studies in diverse helminths, parasitic nematodes appear variably susceptible. To test if this is due to inter-species differences in RNAi effector complements, we performed a primary sequence similarity survey for orthologs of 77 Caenorhabditis elegans RNAi pathway proteins in 13 nematode species for which genomic or transcriptomic datasets were available, with all outputs subjected to domain-structure verification. Our dataset spanned transcriptomes of Ancylostoma caninum and Oesophagostomum dentatum, and genomes of Trichinella spiralis, Ascaris suum, Brugia malayi, Haemonchus contortus, Meloidogyne hapla, Meloidogyne incognita and Pristionchus pacificus, as well as the Caenorhabditis species C. brenneri, C. briggsae, C. japonica and C. remanei, and revealed that: (i Most of the C. elegans proteins responsible for uptake and spread of exogenously applied double stranded (dsRNA are absent from parasitic species, including RNAi-competent plant-nematodes; (ii The Argonautes (AGOs responsible for gene expression regulation in C. elegans are broadly conserved, unlike those recruited during the induction of RNAi by exogenous dsRNA; (iii Secondary Argonautes (SAGOs are poorly conserved, and the nuclear AGO NRDE-3 was not identified in any parasite; (iv All five Caenorhabditis spp. possess an expanded RNAi effector repertoire relative to the parasitic nematodes, consistent with the propensity for gene loss in nematode parasites; (v In spite of the quantitative differences in RNAi effector complements across nematode species, all displayed qualitatively similar coverage of functional protein groups. In summary, we could not identify RNAi effector deficiencies that associate with reduced susceptibility in parasitic nematodes. Indeed, similarities in the RNAi effector complements of RNAi refractory and competent nematode parasites support the broad applicability of this research

  19. Evaluation the effect of albendazole against nematodes in sheep

    Directory of Open Access Journals (Sweden)

    M. I. Al-Farwachi

    2008-01-01

    Full Text Available Six sheep farms in Mosul city, Iraq randomly selected, were surveyed for gastrointestinal nematodes resistant to Albendazole. On each of 6 sheep farms, 20 lambs were randomly distributed into two equal groups untreated control group, and albendazole (benzimidazole group (10 mg/kg BW. Faecal egg counts and larval cultures were done at 7, 14, and 21 days after anthelmintic treatment. Resistance was apparent for albendazole on 4 farms out of 6 (66.7%. Post-treatment larval cultures indicated: Strongyloides papillosus, Marshalligia marshalli, Nematodirus spathiger and Haemonchus contortus.

  20. Laboratory trials to infect insects and nematodes by some acaropathogenic Hirsutella strains (Mycota: Clavicipitaceous anamorphs).

    Science.gov (United States)

    Bałazy, Stanisław; Wrzosek, Marta; Sosnowska, Danuta; Tkaczuk, Cezary; Muszewska, Anna

    2008-02-01

    Laboratory assays have been carried out to artificially infect insect larvae of the birch bark-beetle (Scolytus ratzeburgi Jans.-Coleoptera, Scolytidae) and codling moth Cydia pomonella L. -Lepidoptera, Tortricidae) as well as the potato cyst nematode-Globodera rostochiensis Wollenweber, sugar beet nematode-Heterodera schachtii Schmidt and root-knot nematode-Meloidogyne hapla Chif (Nematoda, Heteroderidae), by the phialoconidia of some fungal species of the genus Hirsutella. From among four species tested on insects only H. nodulosa Petch infected about 20% of S. ratzeburgi larvae, whereas H. kirchneri (Rostrup) Minter, Brady et Hall, H. minnesotensis Chen, Liu et Chen, and H. rostrata Bałazy et Wiśniewski did not affect insect larvae. Only single eggs of the root-knot nematode were infected by H. minnesotensis in the laboratory trials, whereas its larvae remained unaffected. No infection cases of the potato cyst nematode (G. rostochiensis) and sugar beet nematode eggs were obtained. Comparisons of DNA-ITS-region sequences of the investigated strains with GenBank data showed no differences between H. minnesotensis isolates from the nematodes Heterodera glycines Ichinohe and from tarsonemid mites (authors' isolate). A fragment of ITS 2 with the sequence characteristic only for H. minnesotensis was selected. Two cluster analyses indicated close similarity of this species to H. thompsonii as sister clades, but the latter appeared more heterogenous. Insect and mite pathogenic species H. nodulosa localizes close to specialized aphid pathogen H. aphidis, whereas the phytophagous mite pathogens H. kirchneri and H. gregis form a separate sister clade. Hirsutella rostrata does not show remarkable relations to the establishment of aforementioned groups. Interrelated considerations on the morphology, biology and DNA sequencing of investigated Hirsutella species state their identification more precisely and facilitate the establishment of systematic positions.

  1. Penicillium oxalicum reduces the number of cysts and juveniles of potato cyst nematodes.

    Science.gov (United States)

    Martinez-Beringola, M L; Salto, T; Vázquez, G; Larena, I; Melgarejo, P; De Cal, A

    2013-07-01

    To test the biocontrol potential of Penicillium oxalicum, a biocontrol agent against fungal diseases and against the potato cyst nematodes (PCNs), Globodera pallida and Globodera rostochiensis. We tested the effect of P. oxalicum on the nematode cysts under laboratory conditions or in soil microcosms. A reduction in the rate of G. pallida juveniles hatching by P. oxalicum was observed when root diffusates from the 'Monalisa' and the 'Désirée' potato cultivar were used (98·6 and 74·1% reduction, respectively). However, the rate of G. pallida juveniles hatching was not significantly reduced when root diffusates from the 'San Pedro' tomato cultivar were used. Penicillium oxalicum also significantly reduced the ability of the G. rostochiensis juveniles to hatch (30·9% reduction) when root diffusates of the 'Désirée' potato cultivars were used. Penicillium oxalicum treatment of the soil significantly reduced the number of G. pallida cysts that were recovered from the soil of each pot that contained the 'Désirée' potato cultivar. Our results show that P. oxalicum is a potential biocontrol inoculant for protecting potato crops against PCNs. Penicillium oxalicum has potential to be used in order to reduce PCNs. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

  2. Comparing the efficacy of four immersion flush and static hydorgen peroxide and copper sulfate treatments on channel catfish eggs infected with water molds

    Science.gov (United States)

    Water mold infestations on channel catfish eggs lower the hatch rate (egg survival) and ultimately the number of catfish fry available for stocking in production ponds. This study compared the potential of two hydrogen peroxide (HP) and two copper sulfate pentahydrate (CSP) treatments to increase c...

  3. Evaluation of acetone vapors toxicity on Plodia interpunctella (Hubner) (Lepidoptera: Pyralidae) eggs.

    Science.gov (United States)

    Pourmirza, Ali Asghr; Nasab, Fershteh Sadeghi; Zadeh, Abas Hossein

    2007-08-01

    The efficacy of acetone vapors against carefully aged eggs of Plodia interpunctella (Hubner) at 17+/-1 and 27+/-1 degrees C at different dosage levels of acetone over various exposure times was determined. Acetone was found to be toxic to Indian meal moth eggs. Considerable variation in the susceptibility of different age groups of eggs was apparent in the fiducial limits of the LD50 values. An inverse relationship between LD50 values and exposure times was observed in age groups of tested eggs. At 27+/-1 degrees C and 24 h exposure period, eggs aged 1-2 day-old were more tolerant to acetone than other age groups, followed by 0-1 day-old, 2-3 day-old and 3-4 day-old eggs. A similar pattern of susceptibility of eggs was observed at 72 h exposure. In all bioassays, eggs exposed to higher dosages of acetone developed at smaller rate. This was significant for the eggs, which were exposed to the highest dosage for 24 h. Increasing the temperature from 17+/-1 to 27+/-1 degrees C greatly increased the efficacy of acetone. At 27+/-1 degrees C eggs of P. interpunctella were killed by less than one-third of the dosage required for control at 17+/-1 degrees C. Acetone achieved 50% mortality with a dosage of 82.76 mg L(-1) in 1-2 day-old eggs at 27+/-1 degrees C. At this temperature hatching was retarded and greatly diminished when eggs aged 1-2 day-old were exposed to 80 mg L(-1) of acetone for the 24 h exposure period. There was no evidence of a hatch delay longer than the time spent under vapors for eggs exposed at 17+/-1 or 27+/-1 degrees C, indicating that some development must have occurred under fumigation.

  4. The Insect Growth Regulator Pyriproxyfen Terminates Egg Diapause in the Asian Tiger Mosquito, Aedes albopictus.

    Directory of Open Access Journals (Sweden)

    Devi S Suman

    Full Text Available The Asian tiger mosquito, Aedes albopictus, is a highly invasive mosquito species that transmits chikungunya and dengue. This species overwinters as diapausing eggs in temperate climates. Early diapause termination may be a beneficial strategy for winter mosquito control; however, a mechanism to terminate the diapause process using chemicals is not known. We tested the hypothesis that a hormonal imbalance caused by the administration of juvenile hormone analog would terminate egg diapause in A. albopictus. We tested the insect growth regulator pyriproxyfen on all developmental stages to identify a susceptible stage for diapause termination. We found that pyriproxyfen treatment of mosquito eggs terminated embryonic diapause. The highest rates of diapause termination were recorded in newly deposited (78.9% and fully embryonated (74.7% eggs at 0.1 and 1 ppm, respectively. Hatching was completed earlier in newly deposited eggs (25-30 days compared to fully embryonated eggs (71-80 days. The combined mortality from premature diapause termination and ovicidal activity was 98.2% in newly deposited and >98.9% in fully embryonated eggs at 1 ppm. The control diapause eggs did not hatch under diapausing conditions. Pyriproxyfen exposure to larvae, pupae and adults did not prevent the females from ovipositing diapausing eggs. There was no effect of pyriproxyfen on diapausing egg embryonic developmental time. We also observed mortality in diapausing eggs laid by females exposed to pyriproxyfen immediately after blood feeding. There was no mortality in eggs laid by females that survived larval and pupal exposures. In conclusion, diapausing eggs were the more susceptible to pyriproxyfen diapause termination compared to other life stages. This is the first report of diapause termination in A. albopictus with a juvenile hormone analog. We believe our findings will be useful in developing a new control strategy against overwintering mosquito populations.

  5. Monitoring System and Temperature Controlling on PID Based Poultry Hatching Incubator

    Science.gov (United States)

    Shafiudin, S.; Kholis, N.

    2018-04-01

    Poultry hatching cultivation is essential to be observed in terms of temperature stability by using artificial penetration incubator which applies On/Off control. The On/Off control produces relatively long response time to reach steady-state conditions. Moreover, how the system works makes the component worn out because the lamp is on-off periodically. Besides, the cultivation in the market is less suitable to be used in an environment which has fluctuating temperature because it may influence plant’s temperature stability. The study aims to design automatic poultry hatching cultivation that can repair the temperature’s response of plant incubator to keep stable and in line with the intended set-point temperature value by using PID controller. The method used in PID controlling is designed to identify plant using ARX (Auto Regressive eXogenous) MATLAB which is dynamic/non-linear to obtain mathematical model and PID constants value that is appropriate to system. The hardware design for PID-based egg incubator uses Arduino Uno R3, as the main controller that includes PID source, and PWM, to keep plant temperature stability, which is integrated with incandescent light actuators and sensors where DHTI 1 sensor as the reader as temperature condition and plant humidity. The result of the study showed that PID constants value of each plant is different. For parallel 15 Watt plant, Kp = 3.9956, Ki = 0.361, Kd = 0, while for parallel 25 Watt plant, the value of Kp = 5.714, Ki = 0.351, Kd = 0. The PID constants value were capable to produce stable system response which is based on set-point with steady state error’s value is around 5%, that is 2.7%. With hatching percentage of 70-80%, the hatching process is successful in air-conditioned environment (changeable).

  6. Nest site selection and hatching success of hawksbill and loggerhead sea turtles (Testudines, Cheloniidae at Arembepe Beach, northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Thiago Zagonel Serafini

    2009-07-01

    Full Text Available Nest site selection influences the hatching success of sea turtles and represents a crucial aspect of their reproductive process. Arembepe Beach, in the State of Bahia, northeastern Brazil, is a known nest site for Caretta caretta and Eretmochelys imbricata. For the nesting seasons in 2004/2005 and 2005/2006, we analyzed the influence of beach profile and amount of beach vegetation cover on nest site selection and the hatching success for both species. Loggerhead turtles nested preferentially in the sand zone, while hawksbill turtles demonstrated no preferences for either sand or vegetation zone. Beach vegetation was important in the modulation of nest site selection behavior for both species, but the amount of beach vegetation cover influenced (negatively hatching success only for the hawksbill, mainly via the increment of non-hatched eggs.Hatching success, outside the tide risk zone, was not influenced by the position of the nests along the beach profile. The pattern of nest distribution by species indicated that management of nests at risk of inundation and erosion by the tide is more important for loggerhead turtles than for hawksbill turtles. Beach vegetation is animportant factor in the conservation of these sea turtle species. Nests that are at risk due to tidal inundation and erosion can be translocated to any position along the beach profile without producing any significant effect on hatching success, as long as highdensities of beach vegetation cover are avoided for hawksbill nests. It is important to point out that the pattern we report here for distribution of hawksbill nests along the beach profile could be due in part to the influence of pure and hybrid individuals, since there are reports of hybridization among hawksbills and loggerheads to the study site.

  7. Have eggs. Will travel

    DEFF Research Database (Denmark)

    Kroløkke, Charlotte

    2015-01-01

    Feminist scholars have critically questioned the practices and ethics of reproductive mobility. While the reproductive mobility of fertility patients has been foregrounded, little is known of egg donor mobility including the experiences of travelling internationally to donate eggs. Based on written...... stories and photographic material provided by forty-two egg donors, this article uses feminist cluster analysis and the concept of eggpreneurship to illustrate how global egg donors negotiate reproductive agency and choice when they travel internationally to donate their eggs. In their stories, global egg...

  8. Life-stage-specific differences in exploitation of food mixtures: diet mixing enhances copepod egg production but not juvenile development

    DEFF Research Database (Denmark)

    Koski, Marja; Breteler, W.K.; Schogt, N.

    2006-01-01

    , the copepods failed to moult past the first copepodite stage, and the mortality was high. In sharp contrast, mixing two nutritionally poor food species often resulted in egg production which was not significantly different from nutritionally high quality food, although hatching success in many mixtures was low......Development, egg production and hatching success of the calanoid copepods Temora longicornis and Pseudocalanus elongatus were measured in food mixtures to test their ability to obtain a complete nutrition by combining different nutritionally poor food species. In all the food mixtures used....... Whereas egg production was significantly correlated with particulate organic nitrogen in the diet, and independent of the highly unsaturated fatty acids (HUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), hatching increased with increasing DHA and EPA concentration. Growth and juvenile...

  9. Hatching phenology and voltinism of Heterocypris barbara (Crustacea: Ostracoda from Lampedusa (Sicily, Italy

    Directory of Open Access Journals (Sweden)

    Valeria Rossi

    2013-04-01

    Full Text Available The persistence of crustacean populations in ephemeral ponds requires appropriate adaptations in life history strategies (e.g. in hatching phenology. Organisms take advantage of pond filling when it occurs and hedge their bets for the possibility to complete one or more life cycles or to produce resting stages that ensure that the population will not go extinct. We carried out laboratory experiments to investigate the dynamics of a sexual population of Heterocypris barbara from a vernal pool in Lampedusa Island (Sicily. Experimental organisms were obtained hydrating sediments from Aria Rossa temporary pond. Recruitment from resting eggs, voltinism, mean body size and sex ratio were observed in microcosms at different conductivities (high 2.0-2.7 mS cm-1, intermediate 1.0-1.1 mS cm-1 and low 0.5-0.6 mS cm-1. Microcosms were kept in laboratory controlled conditions: constant (24°C 12:12 L:D and 16°C 10:14 L:D photoperiod or fluctuating thermal regimes. The experiment lasted 7 months. Resting and non-resting egg production and up to a bivoltine life cycle were observed. Recruitment events from egg bank and voltinism varied by thermal regime and conductivity. A prolonged recruitment phase occurred in conditions that could be considered a proxy of a rainy season (16°C, 10:14 L:D and low conductivity or of long hydroperiods (spring thermal fluctuating regime and intermediate conductivity. At 24°C, age at reproduction of females from resting eggs almost doubled at low conductivity (in comparison with high conductivity. Low conductivity also reduced hatching time of resting eggs while it increased development time and age at maturity. In thermal fluctuating regime, degree-days to reproduction were about double than at constant 24°C. Males, observed in all microcosms, reached maturity faster and had a shorter life span than females. Males initially outnumbered females, but later in the experiments females became dominant. We also evaluated the

  10. Water relations during desiccation of cysts of the potato-cyst nematode Globodera rostochiensis.

    Science.gov (United States)

    Wharton, D A; Worland, M R

    2001-03-01

    The loss during desiccation of osmotically active water (OAW), which freezes during cooling to -45 degrees C, and osmotically inactive water (OIW), which remains unfrozen, from the cysts of the potato cyst nematode, Globodera rostochiensis, was determined using differential scanning calorimetry. Exotherms and endotherms associated with non-egg compartments were not detected after 5 min desiccation at 50% relative humidity and 20 degrees C. The pattern of water loss from the cysts indicates that water is lost from compartments outside the eggs first, that nearly all the non-egg water is OAW and that the OIW content of the cyst is contained within the eggs. Water is lost from the eggs only after the OAW content outside the eggs falls below that within the eggs. Both OAW and OIW are lost from the eggs during desiccation but the eggs retain a small amount of OIW. Other animals which survive some desiccation but which are not anhydrobiotic will tolerate the loss of OAW but not the loss of their OIW. Anhydrobiotic animals can survive the loss of both their OAW and a substantial proportion of their OIW.

  11. The pinewood nematode, Bursaphelenchus xylophilus

    OpenAIRE

    Mota, Manuel; Vieira, Paulo

    2004-01-01

    According to the European Plant Protection Organization, the pinewood nematode (PWN), Bursaphelenchus xylophilus is a quarantine organism at the top of the list of the pathogenic species. PWN may be found in North America (Canada, USA and Mexico) and in East Asia (Japan, Korea, China and Taiwan) and has a highly destructive capability towards conifers, in a relatively short time, causing serious economic damage in Japan, China and Korea. This nematode surveying is extremely imp...

  12. Copper sulfate controls fungus on mat-spawned largemouth bass eggs

    Science.gov (United States)

    Copper sulfate (CuSO4) is widely used by the catfish and hybrid striped bass industries as an economical treatment to control fungus (Saprolegnia spp.) on eggs; these industries use hatching troughs and McDonald jars, respectively, in moderate alkalinity waters. This study determined the effectivene...

  13. Efficacy of Sodium Carbonate Peroxyhydrate as A Catfish Egg Disinfectant and Comparison to Hydrogen Peroxide

    Science.gov (United States)

    Two experiments were conducted to evaluate the efficacy of sodium carbonate peroxyhydrate (SCP) for improving channel catfish Ictalurus punctatus hatching success when used as a prophylactic chemotherapeutant during egg incubation. In the first experiment, efficacy of SCP was evaluated in 379-L, al...

  14. Clutch morphology and the timing of exposure impact the susceptibility of aquatic insect eggs to esfenvalerate.

    Science.gov (United States)

    Palmquist, Katherine R; Jenkins, Jeffrey J; Jepson, Paul C

    2008-08-01

    We investigated Baetis spp. (mayfly), Hesperoperla pacifica (stonefly), and Brachycentrus americanus (caddisfly) susceptibility at the egg stage to esfenvalerate, a synthetic pyrethroid insecticide. Eggs were obtained from the field or from field-collected gravid females at sites near Corvallis (OR, USA) and the Metolius River at Camp Sherman (OR, USA) for static exposures under controlled conditions for temperature and light. Eggs were exposed to esfenvalerate for 48 h at concentrations ranging from 0.025 to 4.0 microg/L. No effect on mortality or posthatch growth was detected in H. pacifica eggs exposed to esfenvalerate concentrations up to 1.0 microg/L. Exposure to 0.07 microg/L of esfenvalerate, however, caused a significant increase in Baetis spp. egg mortality, and exposure of near-eclosion eggs to lower concentrations (0.025 and 0.05 microg/L) resulted in behavioral effects and reduced survivorship in newly hatched Baetis nymphs. Early stage B. americanus eggs were 10-fold more sensitive to esfenvalerate when removed from the gelatinous clutch before exposure, an indication that the gelatin affords protection from toxicant exposure. Exposures of near-hatch B. americanus clutches to esfenvalerate concentrations ranging between 0.035 and 0.2 microg/L, however, resulted in significant clutch death within clutches resulting from behavioral aberrations of first-instar larvae. The results of the present study suggest that aquatic insect egg clutch morphology can be a strong influence on susceptibility of embryos to esfenvalerate exposure.

  15. Development of Tribolium castaneum (Herbst) larvae after gamma irradiation of eggs

    International Nuclear Information System (INIS)

    Mehta, V.K.; Sethi, G.R.; Garg, A.K.

    1990-01-01

    Development of Rust-red flour beetle, Tribolium castaneum larvae, after gamma irradiation of eggs of two different age groups was studied. Results indicated that, if 2 to 3 day old eggs were irradiated with 6 Krad, the development of larvae emerging from such eggs is completely arrested at the end of 18 days after hatching. In case of comparatively older eggs (3 to 4 day old), 8 Krad dose of gamma radiation was required to produce the similar results. However, treatment with 10 Krad resulted in 100 per cent egg mortality in both the age groups. The studies thus reveal that survival of the larvae depends not only on the radiation dose and the time period elapsed after irradiation but also on the age of eggs at the time of exposure. (author). 9 refs., 1 tab

  16. The hatching larva of the priapulid worm Halicryptus spinulosus

    OpenAIRE

    Janssen, Ralf; Wennberg, Sofia A; Budd, Graham E

    2009-01-01

    Abstract Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid developmen...

  17. Performance and gastroinstestinal nematode control when meat-goat kids grazed chicory, birdsfoot trefoil, or red clover pasutures

    Science.gov (United States)

    In most pasture-based meat-goat production systems, a major management challenge is control of gastrointestinal nematodes (GIN). Use of legumes and forbs that contain plant secondary compounds may reduce fecal egg count (FEC) and/or improve the overall protein nutrition to help animals better toler...

  18. 21 CFR 160.115 - Liquid eggs.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Liquid eggs. 160.115 Section 160.115 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.115 Liquid eggs. (a) Liquid eggs, mixed eggs, liquid whole eggs, mixed whole eggs are eggs of the domestic...

  19. HATCH-OUT ANALYSIS AND REPEATABILITY ESTIMATES OF ...

    African Journals Online (AJOL)

    AGROSEARCH UIL

    quantifying the problem areas that cause low hatchability (Mauldin, 2003). It allows the hatchery ... (Map data, 2013). The eggs collected from each .... of egg size on heat production and the transition of energy from egg to hatchling. Poult. Sci.,.

  20. Aridity promotes bet hedging via delayed hatching: a case study with two temporary pond crustaceans along a latitudinal gradient.

    Science.gov (United States)

    Pinceel, Tom; Vanschoenwinkel, Bram; Hawinkel, Wouter; Tuytens, Karen; Brendonck, Luc

    2017-05-01

    Climate change does affect not only average rainfall and temperature but also their variation, which can reduce the predictability of suitable conditions for growth and reproduction. This situation is problematic for inhabitants of temporary waters whose reproductive success depends on rainfall and evaporation that determine the length of the aquatic phase. For organisms with long-lived dormant life stages, bet hedging models suggest that a fraction of these should stay dormant during each growing season to buffer against the probability of total reproductive failure in variable environments. Thus far, however, little empirical evidence supports this prediction in aquatic organisms. We study geographic variation in delayed hatching of dormant eggs in natural populations of two crustaceans, Branchinella longirostris and Paralimnadia badia, that occur in temporary rock pools along a 725 km latitudinal aridity gradient in Western Australia. Consistent with bet hedging theory, populations of both species were characterised by delayed hatching under common garden conditions and hatching fractions decreased towards the drier end of the gradient where the probability of reproductive success was shown to be lower. This decrease was most pronounced in the species with the longer maturation time, presumably because it is more sensitive to the higher prevalence of short inundations. Overall, these findings illustrate that regional variation in climate can be reflected in differential investment in bet hedging and hints at a higher importance of delayed hatching to persist when the climate becomes harsher. Such strategies could become exceedingly relevant as determinants of vulnerability under climate change.

  1. Factors affecting fecal egg counts in peri-parturient Katahdin ewes and their lambs

    Science.gov (United States)

    Selection for low fecal egg counts (FEC) can be used to genetically enhance resistance to gastrointestinal nematode parasites in growing lambs, thereby reducing the frequency of use of anthelmintics, facilitating marketing of organic lamb, and reducing the risk of development of anthelmintic resista...

  2. Accuracy of egg flotation throughout incubation to determine embryo age and incubation day in waterbird nests

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2010-01-01

    Floating bird eggs to estimate their age is a widely used technique, but few studies have examined its accuracy throughout incubation. We assessed egg flotation for estimating hatch date, day of incubation, and the embryo's developmental age in eggs of the American Avocet (Recurvirostra americana), Black-necked Stilt (Himantopus mexicanus), and Forster's Tern (Sterna forsteri). Predicted hatch dates based on egg flotation during our first visit to a nest were highly correlated with actual hatch dates (r = 0.99) and accurate within 2.3 ± 1.7 (SD) days. Age estimates based on flotation were correlated with both day of incubation (r = 0.96) and the embryo's developmental age (r = 0.86) and accurate within 1.3 ± 1.6 days and 1.9 ± 1.6 days, respectively. However, the technique's accuracy varied substantially throughout incubation. Flotation overestimated the embryo's developmental age between 3 and 9 days, underestimated age between 12 and 21 days, and was most accurate between 0 and 3 days and 9 and 12 days. Age estimates based on egg flotation were generally accurate within 3 days until day 15 but later in incubation were biased progressively lower. Egg flotation was inaccurate and overestimated embryo age in abandoned nests (mean error: 7.5 ± 6.0 days). The embryo's developmental age and day of incubation were highly correlated (r = 0.94), differed by 2.1 ± 1.6 days, and resulted in similar assessments of the egg-flotation technique. Floating every egg in the clutch and refloating eggs at subsequent visits to a nest can refine age estimates.

  3. A novel bacterial symbiont in the nematode Spirocerca lupi

    Directory of Open Access Journals (Sweden)

    Gottlieb Yuval

    2012-07-01

    Full Text Available Abstract Background The parasitic nematode Spirocerca lupi (Spirurida: Thelaziidae, the canine esophageal worm, is the causative agent of spirocercosis, a disease causing morbidity and mortality in dogs. Spirocerca lupi has a complex life cycle, involving an obligatory coleopteran intermediate host (vector, an optional paratenic host, and a definitive canid host. The diagnosis of spirocercosis is challenging, especially in the early disease stages, when adult worms and clinical signs are absent. Thus, alternative approaches are needed to promote early diagnosis. The interaction between nematodes and their bacterial symbionts has recently become a focus of novel treatment regimens for other helminthic diseases. Results Using 16S rDNA-based molecular methods, here we found a novel bacterial symbiont in S. lupi that is closely related to Comamonas species (Brukholderiales: Comamonadaceae of the beta-proteobacteria. Its DNA was detected in eggs, larvae and adult stages of S. lupi. Using fluorescent in situ hybridization technique, we localized Comamonas sp. to the gut epithelial cells of the nematode larvae. Specific PCR enabled the detection of this symbiont's DNA in blood obtained from dogs diagnosed with spirocercosis. Conclusions The discovery of a new Comamonas sp. in S. lupi increase the complexity of the interactions among the organisms involved in this system, and may open innovative approaches for diagnosis and control of spirocercosis in dogs.

  4. Food crystallization and eggs.

    Science.gov (United States)

    Egg products can be utilized to control crystallization in a diverse realm of food products. Albumen and egg yolk can aid in the control of sugar crystal formation in candies. Egg yolk can enhance the textural properties and aid in the control of large ice crystal formation in frozen desserts. In...

  5. Does a Change from Whole to Powdered Food (Artemia franciscana eggs Increase Oviposition in the Ladybird Coleomegilla maculata?

    Directory of Open Access Journals (Sweden)

    Eric W. Riddick

    2015-09-01

    Full Text Available The limited availability of alternative foods to replace natural prey hinders cost-effective mass production of ladybird beetles for augmentative biological control. We compared the effects of powdered vs. whole Artemia franciscana (A. franciscana (brine shrimp eggs with or without a dietary supplement on development and reproduction of Coleomegilla maculata (C. maculata (Coleoptera: Coccinellidae. We tested the hypotheses that (1 powdered A. franciscana eggs are more suitable than whole eggs; and (2 palmitic acid, a common fatty acid in natural prey, i.e., aphids, is an effective dietary supplement. Development time, pre-imaginal survival, sex ratio, and body weight of adults did not differ significantly amongst individuals fed powdered vs. whole eggs, with or without 5% palmitic acid. Significantly more oviposition occurred when females were fed powdered eggs than whole eggs and powdered eggs with 5% palmitic acid than whole eggs with or without 5% palmitic acid. A weak functional relationship was found between pre-oviposition time and total oviposition by females fed powdered eggs with 5% palmitic acid; pre-oviposition time decreased as oviposition increased. Food treatments had no significant differential effect on progeny (egg hatch rate. In conclusion, a simple change in A. franciscana egg texture and particle size (i.e., blending whole eggs into a dust-like powder increases oviposition in C. maculata. Supplementing powdered eggs with 5% palmitic acid might accelerate oogenesis (egg maturation in some females.

  6. Effects of egg storage on hatchability, chick quality, performance and immunocompetence parameters of broiler chickens.

    Science.gov (United States)

    Goliomytis, Michael; Tsipouzian, Theofania; Hager-Theodorides, Ariadne L

    2015-09-01

    Pre-incubation egg storage is a necessity for the poultry industry. This study evaluated the effects of pre-incubation storage length of broiler eggs on hatchability, 1-day-old chick quality, subsequent performance, and immunocompetence. To this end, a total of 360 hatching eggs were stored for 4, 12, or 16 d prior to incubation. Hatchability and chick quality were assessed at hatch, and growth performance and immunocompetence parameters were assessed during a 35 d rearing period. Hatchability of set and fertile eggs, and embryonic mortality, were not affected by egg storage. On the contrary, 1-day-old chick BW and length were linearly negatively correlated with egg storage length (P-linearegg weight prior to setting was unaffected, and corrected chick length was positively affected by storage length. One-day-old chick Tona score, navel quality, and post-hatch growth performance (BW at 7 and 35 d, cumulative feed intake, and feed conversion ratio at 35 d) were unaffected by egg storage (P, P-linear>0.05). Lymphoid organ weights at 2 and 35 d, the titre of maternal anti-NDV antibodies, most of the thymocyte subpopulations defined by CD3, CD4, and CD8 cell surface expression in the thymus of 2-d-old chicks, cellular responses to the PHA skin test, humoral responses to primary SRBC, and NDV immunizations were also not influenced by length of storage (P, P-linear>0.05). On the contrary, the length of egg storage was found to negatively influence the abundance of CD3+CD4-CD8- thymocytes that represent the majority of γδ-T cells in the thymus of 2-day-old chicks, as well as the humoral response to booster NDV immunization of the birds. In brief, pre-incubation storage of broiler hatching eggs for up to 16 d did not affect most developmental and growth parameters investigated, except for BW and length at hatch. Egg storage was found to suppress some aspects of the immunocompetence of the birds, particularly aspects of acquired immunity. © 2015 Poultry Science

  7. [Nematodes with zoonotic potential in parks of the city of Tunja, Colombia].

    Science.gov (United States)

    Díaz-Anaya, Adriana María; Pulido-Medellín, Martín Orlando; Giraldo-Forero, Julio César

    2015-01-01

    To identify the presence of parasites with zoonotic potential in major parks in the city of Tunja, Boyacá. Twenty eight parks in the city were selected, where 124 samples of feces of dogs and soil were collected with the help of a spatula, gathering approximately 150 g per sample. They were processed by the method of concentration of Ritchie modified making the identification of parasitic forms in an optical microscope. A 60.7% of the parks were positive to nematodes in samples of canine fecal material and 100% on soil. Found nematodes were eggs and larvae of Toxocara spp., Ancylostoma spp., Trichuris vulpis and Strongiloides spp. This study demonstrated the potential risk of transmission of zoonoses caused by nematodes in canines and for the need to strengthen public health measures to reduce the risk shows the population exposed to such zoonoses.

  8. Effects of dietary fatty acids on the production and quality of eggs and larvae of Atlantic cod (Gadus morhua L.)

    DEFF Research Database (Denmark)

    Røjbek, Maria; Støttrup, Josianne; Jacobsen, Charlotte

    2014-01-01

    Cultivated Atlantic cod (Gadus morhua) entering their first year of gamete maturation were fed diets with different levels of arachidonic acid (ARA) and eicosapentaenoic acid (EPA) for 6.5 months prior to commencement of spawning. Gravid females were stripped three times: at the beginning, peak......–173% higher in eggs than in diets. Cod fed the diet with the lowest EPA/ARA ratio had the greatest egg production. Eggs from fish on a diet with high ARA level had significantly higher fertilization and hatching success than those fed low levels of ARA. This diet produced on average 71 viable eggs g 1 female...

  9. Effects of Demersal Otter Trawls on the Re-suspension of Copepod Resting Eggs and its Potential Effects on Recruitment

    DEFF Research Database (Denmark)

    Hansen, Benni Winding; Drillet, Guillaume; Hay, G

    2014-01-01

    Resting eggs are important phases in the life strategy of many coastal and estuarine copepods. The egg mortality in the sediment layers where they are buried, as well as re-suspension from the sediment into the water column where eggs may hatch are factors that affect the success of this life str...... and recruit nauplii to the pelagic, egg viability was reduced by the passage of the gear components. This study also suggests that the viability is dependent on the gear component and accordingly potential effects must be considered for at this level....

  10. Comparison of the radiosensitivity of dry dormant eggs, gemmules, and statoblasts of three invertebrate forms

    International Nuclear Information System (INIS)

    Shimada, Atsuko; Egami, Nobuo

    1985-01-01

    Radiosensitivities of the special structures (reproductive organs) of various invertebrate animals were examined. The doses of 50 % hatch were about 5 kR for staboblasts of the bryozoa, Pectinatella magnifica; 70 kR for gemmules of the freshwater sponge, Eunapius fragilis; 130 kR for gemmuls of the freshwater sponge, Ephydatia fluviatilis; 180 kR for dry eggs of the rotifer, Brachionus plicatilis, and 350 kR for dry eggs of Artemia salina. The results showed that Artemia eggs were the most radioresistant reproductive organ among the materials examined. (author)

  11. Labelling of eggs of Ceratitis capitata (Wiedmann) through radioactive sperm ( 32p)

    International Nuclear Information System (INIS)

    Wiendl, F.M.; Pacheco, J.M.

    1975-06-01

    The labelling of Med-fly eggs, using the sperm in the transmission of radioisotope 32 P is described. A hundred hatched couples were used, the males fed on a diet made of 5 g sugar and 1.66g of hydrolized protein. This diet was labelled with a solution of Na 2 HPO 4 , in which the atom of phosphorus was labelled with 32 P isotope. It showed an activity calculated at 343,9 μCi. Statistical treatment of the data indicated that the eggs became labelled and remained labelled until the 5th day after mating, even on eggs laid by female who mated with untreated males

  12. Distribution and mortality of diapause eggs from calanoid copepods in relation to sedimentation regimes

    DEFF Research Database (Denmark)

    Sichlau, Mie Hylstofte; Hansen, Jørgen L.S.; Andersen, Thorbjørn J.

    2011-01-01

    Distribution, abundance and age of diapause eggs from three species of calanoid copepods (in particular from Acartia spp. most likely Acartia tonsa, and Centropages hamatus and less numerous from Temora longicornis) were recorded in sediment profiles by enumerating hatched nauplii from incubated...... between the stations. Dating of the sediment cores suggested a ~70-year maximum age of viable eggs on the northernmost stations, and ~28 year at the southernmost stations. The eggs exhibited a significantly higher mortality rate at the southernmost stations compared with the northernmost, 0.35–0.53 year−1...

  13. Biometric identification of capillariid eggs from archaeological sites in Patagonia.

    Science.gov (United States)

    Taglioretti, V; Fugassa, M H; Beltrame, M O; Sardella, N H

    2014-06-01

    Numerous eggs of capillariid nematodes have been found in coprolites from a wide range of hosts and in raptor pellets in archaeological samples from Patagonia. The structure and sculpture of the eggshell of these nematodes and their biometry are commonly used for identification. The aim of this study was to determine whether eggs of the genus Calodium with similar morphology, found in different archaeological samples from Patagonia, belong to the same species. For this purpose, capillariid eggs (N= 843) with thick walls and radial striations were studied by permutational multivariate analysis of variance (PERMANOVA). Eggs exhibiting similar shape and structure also showed similar biometry, regardless of the zoological origin of coprolites (P= 0.84), host diet (P= 0.19), character of the archaeological sites (P= 0.67) and chronology (P= 0.66). Thus, they were attributed to the same species. We suggest that an unidentified zoonotic species of the genus Calodium occurred in the digestive tract of a wide range of hosts in Patagonia during the Holocene and that both human and animal populations were exposed to this parasite during the Holocene in the study area.

  14. Optimizing the efficacy of Paecilomyces lilacinus (strain 251) for the control of root-knot nematodes.

    Science.gov (United States)

    Kiewnick, S; Sikora, R A

    2004-01-01

    The egg pathogenic fungus Paecilomyces lilacinus (strain 251) is a biocontrol fungus with a potential range of activity to control the worldwide most important plant parasitic nematodes. This biological nematicide may be an useful tool in an integrated approach to control mainly sedentary nematodes. Greenhouse experiments were conducted with the root-knot nematodes Meloidogyne incognita and M. hapla on tomato. P. lilacinus, formulated as WG (BIOACT WG), was incorporated into soil inoculated with root-knot nematode eggs prior to transplanting the susceptible tomato cultivar "Hellfrucht". Furthermore, soil treatments were combined with seedling treatments 24 hours before transplanting and a soil drench 2 weeks after planting, respectively. Seedling and post planting treatment was also combined with a soil treatment at planting. All single or combination treatments tested decreased the gall index and the number of egg masses compared to the untreated control 12 weeks after planting. However, the combination of the seedling treatment with a pre- or at-planting application of P. lilacinus was necessary to achieve higher levels of control. Additional post plant drenching resulted in only a slight increase In efficacy. To the feasibility of this modified application system for the control of root-knot nematodes, a yield experiment was conducted with M. hapla and the susceptible cultivar "Gnom F1 Hybrid". It could be demonstrated that the above mentioned combination of pre-planting application plus the seedling and one post plant drench gave the best control and resulted in a significant fruit yield increase in concurrence with a decrease in number of galls per root.

  15. Chitosan Increases Tomato Root Colonization by Pochonia chlamydosporia and Their Combination Reduces Root-Knot Nematode Damage

    Directory of Open Access Journals (Sweden)

    Nuria Escudero

    2017-09-01

    Full Text Available The use of biological control agents could be a non-chemical alternative for management of Meloidogyne spp. [root-knot nematodes (RKN], the most damaging plant-parasitic nematodes for horticultural crops worldwide. Pochonia chlamydosporia is a fungal parasite of RKN eggs that can colonize endophytically roots of several cultivated plant species, but in field applications the fungus shows a low persistence and efficiency in RKN management. The combined use of P. chlamydosporia with an enhancer could help its ability to develop in soil and colonize roots, thereby increasing its efficiency against nematodes. Previous work has shown that chitosan enhances P. chlamydosporia sporulation and production of extracellular enzymes, as well as nematode egg parasitism in laboratory bioassays. This work shows that chitosan at low concentrations (up to 0.1 mg ml-1 do not affect the viability and germination of P. chlamydosporia chlamydospores and improves mycelial growth respect to treatments without chitosan. Tomato plants irrigated with chitosan (same dose limit increased root weight and length after 30 days. Chitosan irrigation increased dry shoot and fresh root weight of tomato plants inoculated with Meloidogyne javanica, root length when they were inoculated with P. chlamydosporia, and dry shoot weight of plants inoculated with both P. chlamydosporia and M. javanica. Chitosan irrigation significantly enhanced root colonization by P. chlamydosporia, but neither nematode infection per plant nor fungal egg parasitism was affected. Tomato plants cultivated in a mid-suppressive (29.3 ± 4.7% RKN egg infection non-sterilized clay loam soil and irrigated with chitosan had enhanced shoot growth, reduced RKN multiplication, and disease severity. Chitosan irrigation in a highly suppressive (73.7 ± 2.6% RKN egg infection sterilized-sandy loam soil reduced RKN multiplication in tomato. However, chitosan did not affect disease severity or plant growth irrespective of

  16. In Vivo Production of Entomopathogenic Nematodes.

    Science.gov (United States)

    Shapiro-Ilan, David I; Morales-Ramos, Juan A; Rojas, M Guadalupe

    2016-01-01

    In nature, entomopathogenic nematodes in the genera Heterorhabditis and Steinernema are obligate parasites of insects. The nematodes are used widely as biopesticides for suppression of insect pests. More than a dozen entomopathogenic nematode species have been commercialized for use in biological control. Most nematodes intended for commercial application are produced in artificial media via solid or liquid fermentation. However, for laboratory research and small greenhouse or field trials, in vivo production of entomopathogenic nematodes is the common method of propagation. Additionally, small companies continue to produce nematodes using in vivo methods for application in niche markets. Advances in mechanization and alternative production routes (e.g., production geared toward application of nematodes in infected host cadavers) can improve efficiency and economy of scale. The objective of this chapter is to describe basic and advanced procedures for in vivo production of entomopathogenic nematodes.

  17. Basic and applied research: Entomopathogenic nematodes

    Science.gov (United States)

    Entomopathogenic nematodes in the genera Heterorhabditis and Steinernema kill arthropods with the aid of their bacterial symbionts. These nematodes are potent microbial control agents that have been widely commercialized for control of economically important insect pests. Biocontrol efficacy relies...

  18. Effects of oxamyl on the citrus nematode, Tylenchulus semipenetrans, and on infection of sweet orange.

    Science.gov (United States)

    Baines, R C; Small, R H

    1976-04-01

    Foliar sprays of 4 microg/ml oxamyl on sweet orange trees in a greenhouse slightly depressed the number of Tylenchulus semipenetrans larvae obtained from roots and soil, but similar treatments were not effective in two orchards. Soil drench treatments decreased the number of citrus nematode larvae obtained from roots or soil of citrus plants grown itt a greenhouse and in orchards. Exposure to 5-10 microg/ml of oxamyl in water was lethal to only a few second-stage larvae treated 10 days, and many second-stage larvae in 2.0 microg/ml oxamyl recovered motility when transferred to fresh water. Aqueous solutions of 50 and 100 microg/ml of oxamyl were toxic to citrus nematode larvae. Additional observations indicate that oxamyl interfered with hatch of citrus nematode larvae and was nematistatic and/or protected sweet orange roots from infection. Oxamyl degraded at different rates in two soils. The number of citrus nematode larvae that infected and developed on sweet orange roots was increased by an undetermined product of the degradation of oxamyl in soil, water, and possibly within plants. This product apparently was translocated in roots.

  19. Comparative efficacy of different anthelmintics against fenbendazole-resistant nematodes of pashmina goats.

    Science.gov (United States)

    Ram, H; Rasool, T J; Sharma, A K; Meena, H R; Singh, S K

    2007-08-01

    A trial using albendazole, albendazole plus rafoxanide combination, ivermectin and doramectin was conducted in Pashmina goats having history of fenbendazole resistance to Haemonchus spp. and maintained at high altitude (>2350 m above sea level). Day 0 infection level was variable in different groups of animals and their larval cultures indicated Haemonchus, Trichostrongylus, Ostertagia and Oesophagostomum spp. infection, in addition to Nematodirus spp. as observed in egg counts. Efficacy of drugs was calculated on day 14 post treatment by faecal egg count reduction test (FECRT). Albendazole was least effective (14%) followed by its combination with rafoxanide (54%). However, ivermectin and doramectin were 96% and 94% effective against gastrointestinal nematodes of Pashmina goats. It was concluded that use of albendazole and its combination with rafoxanide are ineffective in controlling the nematodes of goats at this farm; hence, future use must be avoided. However, regular monitoring of the efficacy of ivermectin and doramectin is needed.

  20. Toxicity of nitrogenous fertilizers to eggs of snapping turtles (Chelydra serpentina) in field and laboratory exposures.

    Science.gov (United States)

    de Solla, Shane Raymond; Martin, Pamela Anne

    2007-09-01

    Many reptiles oviposit in soil of agricultural landscapes. We evaluated the toxicity of two commonly used nitrogenous fertilizers, urea and ammonium nitrate, on the survivorship of exposed snapping turtle (Chelydra serpentina) eggs. Eggs were incubated in a community garden plot in which urea was applied to the soil at realistic rates of up to 200 kg/ha in 2004, and ammonium nitrate was applied at rates of up to 2,000 kg/ha in 2005. Otherwise, the eggs were unmanipulated and were subject to ambient temperature and weather conditions. Eggs were also exposed in the laboratory in covered bins so as to minimize loss of nitrogenous compounds through volatilization or leaching from the soil. Neither urea nor ammonium nitrate had any impact on hatching success or development when exposed in the garden plot, despite overt toxicity of ammonium nitrate to endogenous plants. Both laboratory exposures resulted in reduced hatching success, lower body mass at hatching, and reduced posthatching survival compared to controls. The lack of toxicity of these fertilizers in the field was probably due to leaching in the soil and through atmospheric loss. In general, we conclude that nitrogenous fertilizers probably have little direct impacts on turtle eggs deposited in agricultural landscapes.

  1. Ostrich eggs geometry

    Directory of Open Access Journals (Sweden)

    Šárka Nedomová

    2013-01-01

    Full Text Available Precise quantification of the profile of egg can provide a powerful tool for the analysis of egg shape for various biological problems. A new approach to the geometry of a Ostrich’s egg profile is presented here using an analysing the egg’s digital photo by edge detection techniques. The obtained points on the eggshell counter are fitted by the Fourier series. The obtained equations describing an egg profile have been used to calculate radii of curvature. The radii of the curvature at the important point of the egg profile (sharp end, blunt end and maximum thickness are independent on the egg shape index. The exact values of the egg surface and the egg volume have been obtained. These quantities are also independent on the egg shape index. These quantities can be successively estimated on the basis of simplified equations which are expressed in terms of the egg length, L¸ and its width, B. The surface area of the eggshells also exhibits good correlation with the egg long circumference length. Some limitations of the most used procedures have been also shown.

  2. Maternal thyroid hormones enhance hatching success but decrease nestling body mass in the rock pigeon (Columba livia).

    Science.gov (United States)

    Hsu, Bin-Yan; Dijkstra, Cor; Darras, Veerle M; de Vries, Bonnie; Groothuis, Ton G G

    2017-01-01

    Thyroid hormones (THs) - triiodothyronine (T3) and thyroxine (T4) - are essential for embryonic development in vertebrates. All vertebrate embryos are exposed to THs from maternal origin. As maternal TH levels are known to be essential to embryonic development, the natural variation of maternal THs probably represents a pathway of maternal effects that can modify offspring phenotype. However, potential fitness consequences of variation of maternal TH exposure within the normal physiological range and without confounding effects of the mother have never been experimentally investigated. We experimentally manipulated the levels of yolk T3 and T4 within the physiological range in a species in which the embryo develops outside the mother's body, the Rock Pigeon (Columba livia) eggs. Making use of the natural difference of yolk testosterone between the two eggs of pigeon clutches, we were also able to investigate the potential interaction between THs and testosterone. Elevated yolk TH levels enhanced embryonic development and hatching success, and reduced body mass but not tarsus length between day 14 and fledging. The yolk hormones increased plasma T4 concentrations in females but reduced it in males, in line with the effect on metabolic rate at hatching. Plasma concentrations of T3 and testosterone were not significantly affected. The effects of treatment did not differ between eggs with high or low testosterone levels. Our data indicate that natural variation in maternal yolk TH levels affects offspring phenotype and embryonic survival, potentially influencing maternal and chick fitness. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Nematode neuropeptides as transgenic nematicides.

    Directory of Open Access Journals (Sweden)

    Neil D Warnock

    2017-02-01

    Full Text Available Plant parasitic nematodes (PPNs seriously threaten global food security. Conventionally an integrated approach to PPN management has relied heavily on carbamate, organophosphate and fumigant nematicides which are now being withdrawn over environmental health and safety concerns. This progressive withdrawal has left a significant shortcoming in our ability to manage these economically important parasites, and highlights the need for novel and robust control methods. Nematodes can assimilate exogenous peptides through retrograde transport along the chemosensory amphid neurons. Peptides can accumulate within cells of the central nerve ring and can elicit physiological effects when released to interact with receptors on adjoining cells. We have profiled bioactive neuropeptides from the neuropeptide-like protein (NLP family of PPNs as novel nematicides, and have identified numerous discrete NLPs that negatively impact chemosensation, host invasion and stylet thrusting of the root knot nematode Meloidogyne incognita and the potato cyst nematode Globodera pallida. Transgenic secretion of these peptides from the rhizobacterium, Bacillus subtilis, and the terrestrial microalgae Chlamydomonas reinhardtii reduce tomato infection levels by up to 90% when compared with controls. These data pave the way for the exploitation of nematode neuropeptides as a novel class of plant protective nematicide, using novel non-food transgenic delivery systems which could be deployed on farmer-preferred cultivars.

  4. Preliminary examination of hatching season and growth of ...

    African Journals Online (AJOL)

    The hatching period and the growth of Malawian cyprinid Engraulicypris sardella larvae and juveniles collected from two sites along the southwestern shoreline of Lake Malawi were investigated using otolith increment information. The lapillus was used to determine the age in days following previous studies. The hatching ...

  5. Extraintestinal nematodes of the red fox Vulpes vulpes in north-west Italy.

    Science.gov (United States)

    Magi, M; Guardone, L; Prati, M C; Mignone, W; Macchioni, F

    2015-07-01

    Extraintestinal nematodes of the red fox (Vulpes vulpes) are a wide group of parasites that infect wild and domestic carnivores and occasionally humans. Nematodes in the cardiopulmonary system, stomach, urinary apparatus and muscle tissue of 165 red foxes (Vulpes vulpes) from north-west Italy (Liguria and Piedmont) were investigated between 2009 and 2012. Of the cardiopulmonary nematodes, a high prevalence of Angiostrongylus vasorum and Eucoleus aerophilus (syn. Capillaria aerophila) was found, 78.2% and 41.8% respectively; Crenosoma vulpis (15.8%) and Filaroides spp. (4.8%) were also found. Spirocerca lupi (23.5%), Aonchotheca putorii (syn. Capillaria putorii) (8.6%) and Physaloptera spp. (2.5%) were detected in the stomach and Pearsonema plica (syn. Capillaria plica) (56.8%) in the bladder. Eucoleus boehmi (syn. Capillaria boehmi) was also detected in the nasal cavities of one of the two foxes examined. A coprological examination revealed eggs of E. aerophilus, A. putorii, S. lupi, Physaloptera spp. and eggs of intestinal parasites. Filarial worms were absent in all the 165 animals examined, nor was there evidence of Trichinella spp. in any of the foxes. The foxes were found to host a high prevalence of many species of extraintestinal nematodes. The prevalence of A. vasorum in foxes found in the present study is among the highest in Europe. In addition, to the best of our knowledge, E. boehmi and Filaroides spp. have never been reported before in this host in Italy.

  6. Epidemiology and effects of gastrointestinal nematode infection on milk productions of dairy ewes

    Directory of Open Access Journals (Sweden)

    Suarez V.H.

    2009-06-01

    Full Text Available 66 Pampinta breed ewes were studied during milking to evaluate the infection and the effect of gastrointestinal nematode on milk production sheep system. Naturally infected ewes on pasture were randomly allocated to two groups: TG, suppressively treated group every four weeks with levamisole and UG, untreated group. Faecal nematode egg counts and larval differentiation were conducted monthly. Successive groups of worm free tracer lambs were grazed with ewes and then slaughtered for worm counts. Test-day milk yield of individual ewes was recorded and ewe machine-milking period length (MPL were estimated. Faecal egg counts and tracer nematode numbers increased towards midsummer and declined sharply toward the end of the study. TG (188.0 ± 60 liters produced more (p < 0.066 milk liters than UG (171.9 ± 52.2 and TG had significantly more extended (p < 0.041 MPL than those of UG. The present study showed that dairy sheep were negatively affected by worms, even when exposed to short periods of high acute nematode (mainly Haemonchus contortus infection.

  7. Plant-parasitic nematodes in Hawaiian agriculture

    Science.gov (United States)

    Hawaii’s diverse and mild climate allows for the cultivation of many crops. The introduction of each crop plant brought along its associated nematode pests. These plant-parasitic nematodes became established and are now endemic to the islands. Plantation agriculture determined the major nematode ...

  8. Entomopathogenic nematodes for the biocontrol of ticks.

    Science.gov (United States)

    Samish, M; Glazer, I

    2001-08-01

    Entomopathogenic steinemematid and heterorhabditid nematodes are increasingly used to control insect pests of economically important crops. Laboratory and field simulation trials show that ticks are also susceptible to these nematodes. The authors review the potential of entomogenous nematodes for the control of ticks.

  9. Evaluation of anthelmintic activity of Iris hookeriana against gastrointestinal nematodes of sheep.

    Science.gov (United States)

    Tariq, K A; Chishti, M Z; Ahmad, F; Shawl, A S; Tantray, M A

    2008-06-01

    The objective of this study was to evaluate the anthelmintic efficacy of Iris hookeriana Linn. rhizome against gastrointestinal nematodes of sheep. A worm motility inhibition assay was used for in vitro study and a faecal egg count reduction assay was used for an in vivo study. The in vitro study revealed anthelmintic effects of crude aqueous extracts and crude ethanolic extracts on live Trichuris ovis worms (P < or = 0.05) as evident from their paralysis and/or death at 8 h after exposure. The aqueous extracts of I. hookeriana resulted in a mean worm motility inhibition of 54.0%, while ethanolic extracts resulted in a mean worm motility inhibition of 84.6%. The mean mortality index of aqueous extracts was 0.55, while for ethanolic extracts it was 0.85. The lethal concentration 50 for aqueous extracts was 0.45 mg ml- 1 and for ethanolic extracts it was 0.15 mg ml- 1. The in vivo anthelmintic activity of aqueous and ethanolic extracts of I. hookeriana in sheep naturally infected with mixed species of gastrointestinal nematodes demonstrated a maximum (45.62%) egg count reduction in sheep treated with ethanolic extracts at 2 g kg- 1 body weight on day 10 after treatment, closely followed by ethanolic extracts at 1 g kg- 1 body weight on day 10 after treatment (43.54% egg count reduction). The aqueous extracts resulted in a maximum of 31.53% reduction in faecal egg counts on day 10 after treatment with 1 g kg- 1 body weight. Thus ethanolic extracts exhibited greater anthelmintic activity under both in vitro and in vivo conditions; this could be due to the presence of alcohol-soluble active ingredients in I. hookeriana. From the present study it can be suggested that I. hookeriana rhizome exhibited significant anthelmintic activity against gastrointestinal nematodes of sheep and has the potential to contribute to the control of gastrointestinal nematode parasites of small ruminants.

  10. Eggs containing larvae of Enterobius vermicularis in vaginal smear

    Directory of Open Access Journals (Sweden)

    Jyothi B Shetty

    2012-01-01

    Full Text Available Enterobius vermicularis also known commonly as pinworm is the most common intestinal parasite. It is a nematode that inhabits the human terminal ileum, colon and appendix. The fertilized female migrates to the perianal area where eggs are deposited but occasionally introduces itself into adjacent orifices, most commonly the female genitourinary tract. Thus the eggs can be seen in the vaginal smear as a result of contamination. We report a case wherein the patient presented with signs and symptoms of vulvovaginitis. In her vaginal smear there were eggs of Enterobius vermicularis which showed a coiled larva within it. In the background there were plenty of acute inflammatory cells. This patient responded favorably to antihelminthics. We report this case to highlight the morphology of the parasite and also to emphasize that such findings should not be neglected. Timely reporting and appropriate treatment of such cases will prevent further complications of this parasite including endometritis, salphingitis and peritonitis.

  11. Some Biological studies on the Mediterranean Fruit Fly, Ceratitis capitata (Wiedemann) After Egg Exposure to Acetone, Diethyl Ether, Ethyl Alcohol and Pupal Gamma Irradiation

    International Nuclear Information System (INIS)

    Fadel, A.M.

    2000-01-01

    Some biological studies of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) were carried out to help in controlling this pest. Three laboratory experiments were done to study the effect of acetone, diethyl ether and ethyl alcohol separately or combined with gamma radiation through egg treatment or larval diet treatment. The gamma dose (90 Gy) was applied only on the produced pupae after egg or larval diet treatment. Concentrations of 0, 25, 50 and 100% of each chemical were applied for treating eggs to evaluate egg hatch, pupation, adult emergence and sex ratio. larval diet treatment was done by adding 20 ml of each chemical concentration to 500 gm of larval diet.Treating eggs with ethyl alcohol separately increased pupation significantly at all concentration used while adult emergence was insignificantly increased with the lowest concentration only (25%). Treating larval diet with ethyl alcohol alone increased pupation insignificantly and adult emergence was insignificantly decreased at different concentrations. Moreover, treating eggs or larval diet with diethyl ether alone significantly increased sex ratio at 50% and 2% concentration, respectively,while differed insignificantly by applying different chemicals either on eggs or on larval diet. Treating eggs with the three chemicals before gamma irradiation of the produced pupae fluctuated egg hatch insignificantly compared to gamma irradiation alone. By applying diethyl ether on eggs or acetone in the larval diet decreased egg hatch insignificantly. Competitiveness values were insignificantly increased by applying ethyl alcohol on eggs, acetone or ethyl alcohol on eggs, acetone or ethyl alcohol in larval diet before gamma irradiation of the produced pupae. Survivals of the produced adults, treated as eggs or in the larval diet with different chemicals and irradiated as pupae, fluctuated insignificantly

  12. In vivo assessment of closantel ovicidal activity in Fasciola hepatica eggs.

    Science.gov (United States)

    Solana, María Victoria; Mera y Sierra, Roberto; Scarcella, Silvana; Neira, Gisela; Solana, Hugo Daniel

    2016-01-01

    Anthelmintic resistance in livestock parasites is currently a worldwide problem. Fasciola hepatica is a cosmopolitan parasite which causes considerable loss in sheep and cattle production systems all over the world. Chemotherapy is currently the main tool available for its control. The intensive use of triclabendazole, the drug of choice for more than 20 years, has resulted in the development of resistant strains. The therapeutic options are adulticides such as closantel (salicylanilide anthelmintic that binds extensively to plasma albumin) to treat chronic fascioliasis in sheep, and cattle. In the present work, an Egg Hatch Assay (EHA) and morphometric studies were used to evaluate in vivo the ovicidal activity and morphology F. hepatica eggs, recovered from closantel treated sheep collected at different time intervals post treatment. Statistically significant differences (p < 0.0001) were observed in egg morphometry between the control and the treated groups in all the parameters studied. Eggs recovered from treated animals tend to be narrower and longer. Significant differences were found in the embryonation and hatching of eggs between 36 h post treatment (32, 5%) vs. approximately 85% in control, 12 h and 24 h post treatment. Our results confirm that closantel affects in vivo the normal development of the eggs. As one of the first effects, this drug affects the performance of the trematode's reproductive physiology. Even though closantel treated animals may still eliminate eggs in the first days post treatment, these are not viable. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Laboratory technique for obtaining fathead minnow eggs for use in toxicity experiments

    International Nuclear Information System (INIS)

    Till, J.E.

    1977-01-01

    A laboratory technique for collecting freshly fertilized eggs of the fathead minnow (Pimephales promelas) has been developed for use in toxicity testing of radioactive materials or other environmental pollutants. The fathead minnow egg was selected as a test organism because the period of embryogenesis is relatively short, the number of eggs per spawning is sufficiently large to provide a test group and a control group, and the size of the parent fish is compatible with laboratory facilities. Under a controlled laboratory environment, eggs are available all year. Nesting sites were constructed by cutting plastic pipe in half and covering the inside of the pipe with 1-mm-thick translucent polyethylene. The polyethylene with the eggs attached was removed from the shelter and cut into two pieces, each piece containing approximately the same number of eggs. One piece of polyethylene was floated in the test solution, and the other in spring water as a control. Hatching occurs in 168 h at 24 0 C. Toxicity of the test solution may be scored on the percentage of eggs hatching, the number of abnormal larvae produced, and larval survival

  14. Radiosensitivity of eggs of the rice moth, corcyra cephalonica (STAINT)

    International Nuclear Information System (INIS)

    Abdel-Salam, K.A.

    1991-01-01

    The sensitivity of 1-day-old eggs of Coreyra cephalonica staint., to ionizing radiation has been investigated in view of producing sterile male adults which might help in possible future application of sterile-male technique to control this species. The irradiation effects on subsequent developmental stages were evaluated. A dose of 5 krad was found to prevent hatching of eggs while a dose of 4 krad was the highest dose that allowed an adequate percentage of the irradiated eggs (28.23) to complete development to the adult stage. The mating percentage and mating frequency of resultant adults appeared to be unaffected and the percentage of multiple mating was variable. Egg production and fertility of resulting adults were significantly decreased and all effects of the treatment were more severe for pairings of irradiated males with irradiated females than pairings of either sex with unirradiated partner. However, the results show that a dose of irradiation low enough to permit adequate numbers of adults to develop from irradiated eggs ( 4 krad ) is insufficient to induce high levels of sterility. Thus, it could be concluded that irradiation of eggs for mass production of either sterile or partially sterile adults was found not to be feasible.4 tab., 1 fig

  15. Ocean Warming Enhances Malformations, Premature Hatching, Metabolic Suppression and Oxidative Stress in the Early Life Stages of a Keystone Squid

    Science.gov (United States)

    Rosa, Rui; Pimentel, Marta S.; Boavida-Portugal, Joana; Teixeira, Tatiana; Trübenbach, Katja; Diniz, Mário

    2012-01-01

    Background The knowledge about the capacity of organisms’ early life stages to adapt to elevated temperatures is very limited but crucial to understand how marine biota will respond to global warming. Here we provide a comprehensive and integrated view of biological responses to future warming during the early ontogeny of a keystone invertebrate, the squid Loligo vulgaris. Methodology/Principal Findings Recently-spawned egg masses were collected and reared until hatching at present day and projected near future (+2°C) temperatures, to investigate the ability of early stages to undergo thermal acclimation, namely phenotypic altering of morphological, behavioural, biochemical and physiological features. Our findings showed that under the projected near-future warming, the abiotic conditions inside the eggs promoted metabolic suppression, which was followed by premature hatching. Concomitantly, the less developed newborns showed greater incidence of malformations. After hatching, the metabolic burst associated with the transition from an encapsulated embryo to a planktonic stage increased linearly with temperature. However, the greater exposure to environmental stress by the hatchlings seemed to be compensated by physiological mechanisms that reduce the negative effects on fitness. Heat shock proteins (HSP70/HSC70) and antioxidant enzymes activities constituted an integrated stress response to ocean warming in hatchlings (but not in embryos). Conclusions/Significance The stressful abiotic conditions inside eggs are expected to be aggravated under the projected near-future ocean warming, with deleterious effects on embryo survival and growth. Greater feeding challenges and the lower thermal tolerance limits of the hatchlings are strictly connected to high metabolic demands associated with the planktonic life strategy. Yet, we found some evidence that, in the future, the early stages might support higher energy demands by adjusting some cellular functional properties

  16. Embryo Development and Post-Hatch Performances of Kampung Chicken by in Ovo Feeding of L-Arginine

    Directory of Open Access Journals (Sweden)

    M. Azhar

    2016-12-01

    Full Text Available The research was conducted to evaluate embryo development, post-hatch performances, and growth rate of kampung chicken treated in-ovo feeding of L-Arginine. A total of 135 kampung chicken fertile eggs (weight 42-43 g were used and divided into 5 treatment groups of three replications. They were placed in the semi-automatic incubator. The first group was without in-ovo feeding (negative control; the second group was in-ovo feeding of saline 0.9% (positive control; the 3, 4, and 5 groups were in-ovo feeding of 0.5, 1.0, and 1.5% L-Arginine, respectively. In-ovo feeding of L-Arginine were injected into albumen on day 10 of incubation period using automatic syringe in the narrow end side of egg by inserting needle through a small hole at 10 mm depth. After hatching, all day old chicks were placed in floor pens (1 x 0.5 x 0.5 m accordance with the previous egg groups. The results showed that in-ovo feeding of L-Arginine increased weight and circumference of the embryo, but did not affect the length of embryo. In-ovo feeding of L-Arginine resulted in a higher body weight gain and a lower feed conversion even though feed intake was not significantly different compared to the control groups. The growth rate performance up to 6 weeks rearing increased significantly by increasing L-Arginine administration to 1.0%. It can be concluded that embryo development and post-hatch performances of kampung chicken were markedly increased by in-ovo feeding of L-arginine.

  17. Control of Pathogenicity Root-Knot Nematode (Meloidogyne Javanica by Earthworm Eisenia Feoetida-Based Products in Greenhouse

    Directory of Open Access Journals (Sweden)

    M. Rostami

    2016-06-01

    Full Text Available Introduction: Biocontrol of nematode agents in order to decrease the hazardous impacts of chemical pesticide application including problems of public health and environmental pollution is apriority. In this study, solid (Vermicompost and liquid products (Liquid Vermicompost, Vermiwash and Coelomic fluidof the earthworm species Eisenia fetida were tested against root-knot nematode, Meloidogyne javanica in greenhouse conditions. Materials and Methods: In this study, Solid (Vermicompost and Liquid products(Wormtea, Vermiwash, Coelomic fluid erthworms (Eisenia foetida were tested against Meloidogyne javanica and also the effect of Vermicompost was evaluated on Pathogenicity of various nematode initial inoculum in two stage greenhouse conditions. Earthworm-based products (Vermicompost, Wormtea, Vermiwash and Coelomic fluid were added to tomato pots. Various treatments of liquid as well as solid products and their combination were used in the greenhouse trial. The first Stage greenhouse experiment- Tomato seeds grown in 2 kg sterilized soil. In the treatments having Vermicompost, pots incorporated with 200 gr of this compost homogeneously mixed with soil. After plants reached at two leaf stage, to study the effects of liquid products (Wormtea, Vermiwash, and Coelomic fluid they added to the pots (500cc along with the irrigation water every week and after of 4 leaf stage, 5000 nematode eggs and larva inoculated to the tomato host plants. 90 days after nematode inoculation, plant and nematode growth indices separately measured and compared. The experiment conducted based on completely randomized design having four replicates. The second stage greenhouse experiment- Tomato seeds grown in 2 kg sterilized soil. In the treatments, pots incorporated with 200 gr of this compost homogeneously mixed with soil. After of 4 leaf stage, 0,1000,2000,4000 and 10000 nematode eggs and larva inoculated to the tomato host plants. 90 days after nematode inoculation, plant

  18. Egg introduction: differential allergic responses

    OpenAIRE

    Dosanjh, Amrita

    2017-01-01

    Amrita Dosanjh Medical Center, Rady Childrens Hospital, San Diego, CA, USA Abstract: The use of egg protein preparations in clinical trials to reduce the incidence of egg allergy among infants includes a number of preparations of egg. These include whole egg, egg white protein, and egg yolk preparations. The study of the differential immune responses to these allergenic proteins in comparison is suggested as a future research area of investigation. Keywords: food allergy, egg allergy, clinica...

  19. Efficacy of entomopathogenic nematodes (Rhabditida: Steinernematidae and Heterorhabditidae) on developmental stages of house fly, Musca domestica.

    Science.gov (United States)

    Archana, M; D'Souza, Placid E; Patil, Jagadeesh

    2017-09-01

    The housefly, Musca domestica is a major domestic, medical and veterinary pest. The management of these flies reliance on insecticide, causes environmental constraints, insecticide resistance and residues in the meat, skin. Therefore one of the eco-friendly alternate methods is by using biological agents such as entomopathogenic nematodes (EPN). In the present study evaluated the survival of EPN species Steinernema feltiae , Heterorhabditis indica , S. carpocapsae , S. glaseri and S. abbasi in poultry manure and also their efficacy against different developmental stages of house fly. After exposing to poultry manure, S. feltiae showed more survival as followed by H. indica , S. carpocapsae , S. glaseri and S. abbasi in all exposition period. When the exposition period extended to 96 h, all nematode species survivability was drastically reduced. After exposing these nematodes to poultry manure at 24 h their virulence capacity against wax moth, Galleria mellonella showed all the nematode species were able cause 100% mortality. However their progeny production was significantly reduced. Fly eggs and pupae were refractory to these nematode infection. Petri dish without artificial diet assay showed that, second and 3rd-instar larvae were highly susceptible to EPNs as compared to larvae provided with artificial diet. H. indica showed high virulence capacity compared to other nematodes tested. Poultry manure assay revealed that, H. indica and S. carpocapsae caused minimal mortality where as S. feltiae , S. glaseri and S. abbasi did not cause any mortality. This may be because of poor survival and limited movement of nematodes in poultry manure which may be due to ammonia, other toxic substances in poultry manure. The decrease in larval mortality in manure suggests that biocontrol of housefly by using EPNs is unlikely.

  20. Identification of the Key Weather Factors Affecting Overwintering Success of Apolygus lucorum Eggs in Dead Host Tree Branches

    OpenAIRE

    Pan, Hongsheng; Liu, Bing; Lu, Yanhui; Desneux, Nicolas

    2014-01-01

    Understanding the effects of weather on insect population dynamics is crucial to simulate and forecast pest outbreaks, which is becoming increasingly important with the effects of climate change. The mirid bug Apolygus lucorum is an important pest on cotton, fruit trees and other crops in China, and primarily lays its eggs on dead parts of tree branches in the fall for subsequent overwintering. As such, the eggs that hatch the following spring are most strongly affected by ambient weather fac...

  1. Olive Ridley Sea Turtle Hatching Success as a Function of Microbial Abundance and the Microenvironment of In Situ Nest Sand at Ostional, Costa Rica

    Directory of Open Access Journals (Sweden)

    Vanessa S. Bézy

    2014-01-01

    Full Text Available Sea turtle hatching success at mass nesting beaches is typically lower than at solitary nesting beaches, presumably due in part to high rates of microbial metabolism resulting from the large input of organic matter from turtle eggs. Therefore, we tested the hypothesis that hatching success varies across areas of the beach in conjunction with differences in the physical nest environment and microbial abundance of in situ olive ridley sea turtle nests at Ostional, Costa Rica. We marked natural nests in high-density, low-density, and tidal-wash nesting areas of the beach and monitored clutch pO2 and temperature throughout the incubation period. We quantified hatching success and collected samples of nest sand during nest excavations. We quantified microbial abundance (bacteria and fungi with a quantitative polymerase chain reaction (qPCR analysis. Hatching success was lower in nests with lower pO2, higher temperatures, higher organic matter content, and higher microbial abundance. Our results suggest that the lower oxygen within the nest environment is likely a result of the high microbial abundance and rates of decomposition in the nest sand and that these factors, along with increased temperature of clutches in the high-density nesting area, are collectively responsible for the low hatching success at Ostional.

  2. Comparison of size, terminal fall velocity, and density of bighead carp, silver carp, and grass carp eggs for use in drift modeling

    Science.gov (United States)

    George, Amy E.; Garcia, Tatiana; Chapman, Duane C.

    2017-01-01

    Invasive Asian carp established in the United States spawn in the turbulent water of rivers, and their eggs and early larvae develop while drifting in the current. The eggs, which are believed to perish if they settle before hatching, are slightly denser than water and are held in suspension by water turbulence. It is possible to use egg drift modeling to assess the capability of a river to support the survival of Asian carp eggs. Detection of spawning and estimation of egg abundance in the drift are typically assessed by ichthyoplankton trawls. Correct sampling design and interpretation of trawl data require knowledge of the vertical distribution of eggs in the drift, which can be accomplished with particle transport models. Data that are required to populate models of egg drift and vertical distribution include physical properties of assessed rivers and information on egg size, density, and terminal fall velocity, but data on these egg characteristics have not been previously available. Physical characteristics of the eggs are presented as a function of postfertilization time. We recorded mean egg diameter and terminal fall velocity for eggs from each Asian carp species during the first 5 h of development and at approximately 12 and 22 h postfertilization. Eggs of all species reached their maximum size before 4 h. Water-hardened eggs of Silver Carp Hypophthalmichthys molitrix and Grass Carp Ctenopharyngodon idella were similarly sized in our trials, and water-hardened eggs of Bighead Carp H. nobilis were the largest. After water hardening, Silver Carp eggs sank slowest, and Bighead Carp eggs sank fastest. For a given species, smaller-diameter eggs generally had faster terminal fall velocities and higher specific gravity than larger eggs. We provide regression models of egg density and diameter for all three species, discuss usage of these data in modeling the drift and dispersion of Asian carp eggs, and discuss implications for egg sampling design.

  3. Influence of ultraviolet ray irradiation on length of egg hatchability and on length of incubation period

    International Nuclear Information System (INIS)

    Dimitrov, S.

    1977-01-01

    The effect of irradiation of White Leghorn eggs with ultraviolet rays on their embryonal development, egg hatchability, viability of hatched chicks and their liveweight, is studied. Irradiation length was 1, 3, 5, 10, 15, 20, 40 and 60 min in two experiments and 2, 4, 16 and 256 min in one trial. It was established that egg irradiation with ultraviolet rays affected positively egg hatchability and viability of the chicks, the irradiation effect being strongest in the range of 2 to 40 min. No significant difference was established between liveweight of chicks obtained from irradiated and nonirradiated eggs. It was further found that the length of incubation period was shortened by 2 to 5 hrs with increase in irradiation length over 5 min. (author)

  4. Effect of short-term pre-hatch heat shock of incubating eggs on ...

    African Journals Online (AJOL)

    The six-week live weight of the heat-treated group (2098 ± 12.0 g) was significantly lower than that of the control (2143 ± 12.2 g). The 1-6 ... 1.77 ± 0.03 for the treatment vs. control groups, respectively, but the ... Metrics powered by PLOS ALM

  5. Wolbachia endosymbiont is essential for egg hatching in a parthenogenetic arthropod.

    NARCIS (Netherlands)

    Timmermans, M.J.T.N.; Ellers, J.

    2009-01-01

    Wolbachia pipientis can induce a range of sex ratio distortions including parthenogenesis. Recently Wolbachia has been detected in the diploid, parthenogenetic, collembolan species Folsomia candida. In this paper we address the effect of Wolbachia on reproduction in F. candida. Wolbachia infection

  6. Effects of suspended sediment on the development and hatching of herring (Clupea harengus) eggs

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Frantsen, Erik; Jensen, Carsten

    1981-01-01

    made to test the effect of the increased turbidity near marine mining, spoil disposal or dredging operations. Embryonic development was unaffected by suspended silt. Mortality rates varied significantly between aquaria, but the variation was unrelated to the experimental treatment with silt. Refs....

  7. Effect of short-term pre-hatch heat shock of incubating eggs on ...

    African Journals Online (AJOL)

    These results suggest that prenatal thermal conditioning is not detrimental to broiler growth under standard rearing conditions in the absence of thermal stress. However, survival rate was improved but live weight and FCR were in some cases significantly poorer. Keywords: Heat stress, incubation, parent age, live weight, ...

  8. Predator-prey interactions of nematode-trapping fungi and nematodes: both sides of the coin.

    Science.gov (United States)

    Vidal-Diez de Ulzurrun, Guillermo; Hsueh, Yen-Ping

    2018-05-01

    Nematode-trapping fungi develop complex trapping devices to capture and consume nematodes. The dynamics of these organisms is especially important given the pathogenicity of nematodes and, consequently, the potential application of nematode-trapping fungi as biocontrol agents. Furthermore, both the nematodes and nematode-trapping fungi can be easily grown in laboratories, making them a unique manipulatable predator-prey system to study their coevolution. Several different aspects of these fungi have been studied, such as their genetics and the different factors triggering trap formation. In this review, we use the nematode-trapping fungus Arthrobotrys oligospora (which forms adhesive nets) as a model to describe the trapping process. We divide this process into several stages; namely attraction, recognition, trap formation, adhesion, penetration, and digestion. We summarize the latest findings in the field and current knowledge on the interactions between nematodes and nematode-trapping fungi, representing both sides of the predator-prey interaction.

  9. Odd-Boiled Eggs

    Science.gov (United States)

    Kaminsky, Kenneth; Scheman, Naomi

    2010-01-01

    At a Shabbat lunch in Madrid not long ago, the conversation turned to the question of boiling eggs. One of the guests mentioned that a Dutch rabbi he knew had heard that in order to make it more likely that boiled eggs be kosher, you should add an egg to the pot if the number you began with was even. According to the laws of Kashruth, Jews may not…

  10. Olfactory circuits and behaviors of nematodes.

    Science.gov (United States)

    Rengarajan, Sophie; Hallem, Elissa A

    2016-12-01

    Over one billion people worldwide are infected with parasitic nematodes. Many parasitic nematodes actively search for hosts to infect using volatile chemical cues, so understanding the olfactory signals that drive host seeking may elucidate new pathways for preventing infections. The free-living nematode Caenorhabditis elegans is a powerful model for parasitic nematodes: because sensory neuroanatomy is conserved across nematode species, an understanding of the microcircuits that mediate olfaction in C. elegans may inform studies of olfaction in parasitic nematodes. Here we review circuit mechanisms that allow C. elegans to respond to odorants, gases, and pheromones. We also highlight work on the olfactory behaviors of parasitic nematodes that lays the groundwork for future studies of their olfactory microcircuits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Efficacy of formalin, hydrogen-peroxide, and sodium-chloride on fungal-infected rainbow-trout eggs

    Science.gov (United States)

    Schreier, Theresa M.; Rach, J.J.; Howe, G.E.

    1996-01-01

    Antifungal agents are essential for the maintenance of healthy stocks of fish and their eggs in intensive aquaculture operations. In the usa, formalin is the only fungicide approved for use in fish culture, however, hydrogen peroxide and sodium chloride have been granted low regulatory priority drug status by the united states food and drug administration (fda) and their use is allowed. We evaluated the efficacy of these fungicides for controlling fungal infections on rainbow trout eggs. A pilot study was conducted to determine the minimum water flow rate required to administer test chemicals accurately in heath incubators. A minimum water flow rate of 7.6 1 min(-1) was necessary to maintain treatment concentrations during flow-through chemical exposures, the antifungal activity of formalin, hydrogen peroxide, and sodium chloride was evaluated by treating uninfected and 10% fungal-infected (saprolegnia parasitica) rainbow trout eggs (oncorhynchus mykiss) for 15 min every other day until hatch. There were no significant differences among treatments in percent hatch or final infection for uninfected eggs receiving prophylactic chemical treatments, eggs of the negative control group (uninfected and untreated) had a mean hatch exceeding 86%, all chemical treatments conducted on the infected egg groups controlled the spread of fungus and improved hatching success compared with the positive control groups (infected and untreated), formalin treatments of 1000 and 1500 mu l 1(-1) and hydrogen peroxide treatments of 500 and 1000 mu l 1(-1) were the most effective. Sodium chloride treatments of 30000 mg 1(-1) improved fry hatch, but the compound was less effective at inhibiting fungal growths compared with hydrogen peroxide and formalin treatments.

  12. Eggs: good or bad?

    Science.gov (United States)

    Griffin, Bruce A

    2016-08-01

    Eggs have one of the lowest energy to nutrient density ratios of any food, and contain a quality of protein that is superior to beef steak and similar to dairy. From a nutritional perspective, this must qualify eggs as 'good'. The greater burden of proof has been to establish that eggs are not 'bad', by increasing awareness of the difference between dietary and blood cholesterol, and accumulating sufficient evidence to exonerate eggs from their associations with CVD and diabetes. After 60 years of research, a general consensus has now been reached that dietary cholesterol, chiefly from eggs, exerts a relatively small effect on serum LDL-cholesterol and CVD risk, in comparison with other diet and lifestyle factors. While dietary guidelines have been revised worldwide to reflect this view, associations between egg intake and the incidence of diabetes, and increased CVD risk in diabetes, prevail. These associations may be explained, in part, by residual confounding produced by other dietary components. The strength of evidence that links egg intake to increased CVD risk in diabetes is also complicated by variation in the response of serum LDL-cholesterol to eggs and dietary cholesterol in types 1 and 2 diabetes. On balance, the answer to the question as to whether eggs are 'bad', is probably 'no', but we do need to gain a better understanding of the effects of dietary cholesterol and its association with CVD risk in diabetes.

  13. Egg origin determination efforts

    International Nuclear Information System (INIS)

    Horvath, A.; Futo, I.; Vodila, G.; Palcsu, L.

    2012-01-01

    Complete text of publication follows. As a co-operation with the Poultry Product Board, egg and drinking water samples were received in order to investigate whether the country of origin of the egg can be determined based on its stable isotope composition with the aim of market protection of the Hungarian eggs against the mislabelled foreign ones. The scientific background is that drinking water of egg laying hens is assumed to reflect the composition of regional precipitation, and it is also an input data in the process of egg formation. In the first sampling, altogether 23 sets of egg and drinking water samples were received from different production sites covering the whole area of Hungary. The egg white samples were vacuum distilled and frozen out by liquid nitrogen at -196 deg C. The process was monitored by two vacuum gauges. Water frozen out together with the drinking water samples was measured were measured by a Thermo Finnigan Delta PLUS XP isotope ratio mass spectrometer using a GasBench II peripheral unit equipped with a GC-autosampler. As a second issue, additionally, elemental composition of egg shells were also performed for series of Hungarian, Czech and Polish egg samples by energy dispersive X-ray fluorescence. The drinking waters fit well to the Global Meteoric Water Line indicating their precipitation origin. It was experienced that the water in egg white gets enriched compared to the drinking water (Δ 18 O = -4.9 ± 1.0 per thousand and Δ D = -21.8 ± 6.4 per thousand), however, this shift is independent of the type of the hens, since the mean shifts in the eggs of Tetra and Hy-line hens are similar within error bar. For more depleted drinking water, the shift of the egg white was higher than for more enriched ones. This can be due to the contribution of the nutriment isotopic composition. The water isotope composition of the Hungarian eggs investigated was δ 18 O = -4.8 - -7.3 per thousand and δD = -46.0 - -70.7 per thousand, therefore egg

  14. Ambient ultraviolet radiation causes mortality in salamander eggs

    International Nuclear Information System (INIS)

    Blaustein, A.R.; Edmond, B.; Kiesecker, J.M.

    1995-01-01

    Previous research has shown that amphibian species have differential sensitivity to ultraviolet-B (UV-B) radiation. In some anuran species, ambient levels of UV-B cause mortality in embryonic stages and hatching success is significantly reduced. Projected increases in UV-B may affect an increasing number of species. The adverse effects of UV-B may eventually be manifested at the population level and may ultimately contribute to population declines. Using field experiments, we investigated the effects of ambient UV-B on salamander (Ambystoma gracile) embryos developing at natural oviposition sites. We show that the hatching success of eggs of A. gracile shielded from UV-B is significantly higher than those not shielded from UV-B. 27 refs., 1 fig

  15. Sexual differences in post-hatching Saunders's gulls: size, locomotor activity, and foraging skill.

    Science.gov (United States)

    Yoon, Jongmin; Lee, Seung-Hee; Joo, Eun-Jin; Na, Ki-Jeong; Park, Shi-Ryong

    2013-04-01

    Various selection pressures induce the degree and direction of sexual size dimorphism in animals. Selection favors either larger males for contests over mates or resources, or smaller males are favored for maneuverability; whereas larger females are favored for higher fecundity, or smaller females for earlier maturation for reproduction. In the genus of Larus (seagulls), adult males are generally known to be larger in size than adult females. However, the ontogeny of sexual size dimorphism is not well understood, compared to that in adults. The present study investigates the ontogeny of sexual size dimorphism in Saunders's gulls (Larus saundersi) in captivity. We artificially incubated fresh eggs collected in Incheon, South Korea, and measured body size, locomotor activity, and foraging skill in post-hatching chicks in captivity. Our results indicated that the sexual differences in size and locomotor activity occurred with the post-hatching development. Also, larger males exhibited greater foraging skills for food acquisition than smaller females at 200 days of age. Future studies should assess how the adaptive significance of the sexual size dimorphism in juveniles is linked with sexual divergence in survival rates, intrasexual contests, or parental effort in sexes.

  16. Chemical characteristics and thickness of Podocnemis expansa post-hatching eggshells (Testudines, Podocnemididae

    Directory of Open Access Journals (Sweden)

    Caio Henrique Ferreira

    2016-10-01

    Full Text Available Knowledge on chemical components of the post-hatching eggshell of reptiles may provide indicators of the quality of the diet offered to females kept in captivity. Therefore, the objective of this study was to investigate the chemical characteristics of the calcareous layer, as well as the thickness of Podocnemis expansa post-hatching eggshells. Eggshell thickness was 183±1.405 µm. This value is similar to that of the eggs of other Testudines with flexible eggshells. As for the chemical composition, the following percentages were observed: nitrogen 7.983 ± 0.054; crude protein 49.91 ± 0.324; crude fat 0.068 ± 0.002; mineral matter 20.302 ± 0.807; calcium 13.374 ± 0.647; and phosphorus 0.176 ± 0.003. Knowledge on chemical composition of the eggshell may aid the nutrition of P. expansa raised in commercial facilities, once this species is an alternative and promising source of exotic meat.

  17. Effects of gamma-radiation on eggs of Pomacea Haustrum (Reeve, 1843) from the Pampulha Lake, Belo Horizonte, M. G. (prosobranchia, Pilidae)

    Energy Technology Data Exchange (ETDEWEB)

    Dos Santos Carvalho, O; Milward De Andrade, R; Ricardo C Adriano, A; Mansur Neto, E

    1974-01-01

    Pomacea haustrum eggs, with less than 24 hours after oviposition in the field, were exposed, in groups, to 500, 1,000, 1,500, 2,000, 2,500, 3,000, 3,500, and 4,000 rad, respectively. As regards the irradiated eggs, only 23.9 percent (1,460) achieved eclosion, whose percentage varied according to the gamma-ray dosage used: 41.6 percent for 500 rad; 35.5 percent for 1,000; 21.1 percent for 1,500; 7.9 percent for 2,000; 4.9 percent for 3,000 and, finally, 0.3 percent for 3,500 rad. The 6 egg-masses (1,500 eggs) irradiated with 2,500 rad as well as the 4 (1,401 eggs) exposed to 4,000 rad did not hatch up to 30 days after exposure to gamma-rays. Hatching, among the irradiated eggs, started 11 to 16 days later, their maximum incubation period having ranged from 14 to 16 days. It has also been observed that both the period of incubation and that of recovery of the eggs not irreversibly damaged by the gamma-rays are proportional to the intensity of radiation. Field and laboratory investigations have shown that the eggs in a same mass do not hatch simultaneously, a period of two or more days having already elapsed between the first and last eclosion.

  18. Correlation between real-time qPCR and development of strongyle eggs from cattle

    DEFF Research Database (Denmark)

    Drag, Markus; Nejsum, Peter; Höglund, Johan

    2014-01-01

    Differentiation of veterinary important parasitic strongyle eggs is time-consuming, because morphologically distinct third-stage larvae (L3) must be cultured for species/genus identification. A recently published qPCR technique provides a non-labour intensive method for detection and quantification...... of the two most important nematode eggs in cattle faeces. However, as quantification correlates with DNA content, quantification of copy numbers of the second internal transcribed spacer (ITS2) region is problematic as DNA content increases during egg development. The aim of this study was to assess...... the impact of oxygen availability and temperature on the multiplication of ITS2 copy numbers in O. ostertagi eggs. Fresh eggs were recovered from cattle faeces by sieving, flotation and entrapment in nylon-mesh filters and subsequently deposited in aliquots (n=18) of 5 ml distilled water with air circulation...

  19. How to improve the standardization and the diagnostic performance of the fecal egg count reduction test?

    DEFF Research Database (Denmark)

    Levecke, Bruno; Kaplan, Ray M.; Thamsborg, Stig M.

    2018-01-01

    Although various studies have provided novel insights into how to best design, analyze and interpret a fecal egg count reduction test (FECRT), it is still not straightforward to provide guidance that allows improving both the standardization and the analytical performance of the FECRT across...... a variety of both animal and nematode species. For example, it has been suggested to recommend a minimum number of eggs to be counted under the microscope (not eggs per gram of feces), but we lack the evidence to recommend any number of eggs that would allow a reliable assessment of drug efficacy. Other...... the UI methodology that yields the most reliable assessment of drug efficacy (coverage of TDE) and detection of reduced drug efficacy, and (iii) to determine the required sample size and number of eggs counted under the microscope that optimizes the detection of reduced efficacy. Our results confirm...

  20. Immunity to gastrointestinal nematode infections

    DEFF Research Database (Denmark)

    Sorobetea, D.; Svensson Frej, M.; Grencis, R.

    2018-01-01

    Numerous species of nematodes have evolved to inhabit the gastrointestinal tract of animals and humans, with over a billion of the world's population infected with at least one species. These large multicellular pathogens present a considerable and complex challenge to the host immune system give...

  1. The hatching larva of the priapulid worm Halicryptus spinulosus

    Directory of Open Access Journals (Sweden)

    Budd Graham E

    2009-05-01

    Full Text Available Abstract Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid development. These findings may further help unravelling the phylogenetic position of the Priapulida within the Scalidophora and hence contribute to the elucidation of the nature of the ecdysozoan ancestor.

  2. The hatching larva of the priapulid worm Halicryptus spinulosus.

    Science.gov (United States)

    Janssen, Ralf; Wennberg, Sofia A; Budd, Graham E

    2009-05-26

    Despite their increasing evolutionary importance, basic knowledge about the priapulid worms remains limited. In particular, priapulid development has only been partially documented. Following previous description of hatching and the earliest larval stages of Priapulus caudatus, we here describe the hatching larva of Halicryptus spinulosus. Comparison of the P. caudatus and the H. spinulosus hatching larvae allows us to attempt to reconstruct the ground pattern of priapulid development. These findings may further help unravelling the phylogenetic position of the Priapulida within the Scalidophora and hence contribute to the elucidation of the nature of the ecdysozoan ancestor.

  3. HATCHES - a thermodynamic database and management system

    International Nuclear Information System (INIS)

    Cross, J.E.; Ewart, F.T.

    1990-03-01

    The Nirex Safety Assessment Research Programme has been compiling the thermodynamic data necessary to allow simulations of the aqueous behaviour of the elements important to radioactive waste disposal to be made. These data have been obtained from the literature, when available, and validated for the conditions of interest by experiment. In order to maintain these data in an accessible form and to satisfy quality assurance on all data used for assessments, a database has been constructed which resides on a personal computer operating under MS-DOS using the Ashton-Tate dBase III program. This database contains all the input data fields required by the PHREEQE program and, in addition, a body of text which describes the source of the data and the derivation of the PHREEQE input parameters from the source data. The HATCHES system consists of this database, a suite of programs to facilitate the searching and listing of data and a further suite of programs to convert the dBase III files to PHREEQE database format. (Author)

  4. Anthelmintic resistance in cattle nematodes in the US.

    Science.gov (United States)

    Gasbarre, Louis C

    2014-07-30

    The first documented case of macrocyclic lactone resistance in gastrointestinal (GI) nematodes of cattle was seen in the US approximately 10 years ago. Since that time the increase incidence of anthelmintic resistance has continued at an alarming rate. Currently parasites of the genera Cooperia and/or Haemonchus resistant to generic or brand-name macrocyclic lactones have be demonstrated in more than half of all operations examined. Both of these parasite genera are capable of causing economic losses by decreasing food intake and subsequently animal productivity. Currently, there are no easy and quick means to detect anthelmintic resistant GI nematodes. Definitive identification requires killing of cattle. The most commonly used field detection method is the fecal egg count reduction test (FECRT). This method can be adapted for use as a screening agent for Veterinarians and producers to identify less than desired clearance of the parasites after anthelmintic treatment. Further studies can then define the reasons for persistence of the egg counts. The appearance of anthelmintic resistance is largely due to the development of very effective nematode control programs that have significantly improved the productivity of the US cattle industry, but at the same time has placed a high level of selective pressure on the parasite genome. The challenges ahead include the development of programs that control the anthelmintic resistant nematodes but at the same time result in more sustainable parasite control. The goal is to maintain high levels of productivity but to exert less selective pressures on the parasites. One of the most effective means to slow the development of drug resistance is through the simultaneous use of multiple classes of anthelmintics, each of which has a different mode of action. Reduction of the selective pressure on the parasites can be attained through a more targeted approach to drug treatments where the producer's needs are met by selective

  5. Sex ratios of Mountain Plovers from egg production to fledging

    Directory of Open Access Journals (Sweden)

    Margaret M. Riordan

    2015-12-01

    Full Text Available Skewed sex ratios can have negative implications for population growth if they do not match a species' life history. A skewed tertiary sex ratio has been detected in a population of Mountain Plover (Charadrius montanus, a grassland shorebird experiencing population declines. To study the cause of the observed male skew, we examined three early life stages between egg and fledgling in eastern Colorado from 2010 to 2012. This allows us to distinguish between egg production and chick survival as an explanation for the observed skew. We examined the primary sex ratio in eggs produced and the secondary sex ratio in hatched chicks to see if the sex ratio bias occurs before hatching. We also determined the sex ratio at fledging to reveal sex-specific mortality of nestlings. The primary sex ratio was 1.01 (± 0.01 males per female. The secondary sex ratio consisted of 1.10 (± 0.02 males per female. The probability of a chick surviving to fledging differed between males (0.55 ± 0.13 and females (0.47 ± 0.15, but the precision of these survival estimates was low. Sex ratios in early life stages of the Mountain Plover do not explain the skewed sex ratio observed in adults in this breeding population.

  6. 21 CFR 160.180 - Egg yolks.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Egg yolks. 160.180 Section 160.180 Food and Drugs... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.180 Egg yolks. (a) Egg yolks, liquid egg yolks, yolks, liquid yolks are yolks of eggs of the domestic hen so...

  7. Biogeography of Parasitic Nematode Communities in the Galápagos Giant Tortoise: Implications for Conservation Management.

    Directory of Open Access Journals (Sweden)

    Guillaume Fournié

    Full Text Available The Galápagos giant tortoise is an icon of the unique, endemic biodiversity of Galápagos, but little is known of its parasitic fauna. We assessed the diversity of parasitic nematode communities and their spatial distributions within four wild tortoise populations comprising three species across three Galápagos islands, and consider their implication for Galápagos tortoise conservation programmes. Coprological examinations revealed nematode eggs to be common, with more than 80% of tortoises infected within each wild population. Faecal samples from tortoises within captive breeding centres on Santa Cruz, Isabela and San Cristobal islands also were examined. Five different nematode egg types were identified: oxyuroid, ascarid, trichurid and two types of strongyle. Sequencing of the 18S small-subunit ribosomal RNA gene from adult nematodes passed with faeces identified novel sequences indicative of rhabditid and ascaridid species. In the wild, the composition of nematode communities varied according to tortoise species, which co-varied with island, but nematode diversity and abundance were reduced or altered in captive-reared animals. Evolutionary and ecological factors are likely responsible for the variation in nematode distributions in the wild. This possible species/island-parasite co-evolution has not been considered previously for Galápagos tortoises. We recommend that conservation efforts, such as the current Galápagos tortoise captive breeding/rearing and release programme, be managed with respect to parasite biogeography and host-parasite co-evolutionary processes in addition to the biogeography of the host.

  8. Factors related to shell deaths during artificial incubation of ostrich eggs

    Directory of Open Access Journals (Sweden)

    Z. Brand

    2007-06-01

    Full Text Available he ostrich industry experiences a high rate of embryonic mortalities during artificial incubation of eggs. Embryonic deaths were studied from data recorded on 37 740 fertile eggs incubated artificially during the 1998-2005 breeding seasons. Roughly 10 000 eggs that sustained embryonic mortalities were classified according to the stage and nature of death, i.e. before 21 days of incubation, after 21 days of incubation, deaths after pipping and rotten eggs. Although infection may have played a role in ~1300 rotten eggs, no detailed knowledge of the pathogens involved was available. The remainder of deaths could not be related to pathogens and the deaths were thus generally referred to as non-infectious. The overall level of embryonic mortality in all the eggs studied was 28.5 %. Overall embryonic mortality was affected by incubator, with higher levels (57.0 % found in eggs incubated in an African Incubator(R and also in eggs that were transferred between incubators during incubation (38.1 %. Overall embryonic mortality also increased in eggs produced by older females. Eggs produced in the autumn had the highest level of embryonic mortality at 53.6 %, whereas eggs produced in the winter had a marginally higher level of embryonic mortalities of 29.2 % compared with eggs produced during summer (27.4 %. Eggs produced by South African (SA Black males crossed to Zimbabwean Blue females had high levels of embryonic losses of 45.7 %. The embryonic mortality of eggs produced by SA Blacks or Zimbabwean Blue breeding birds subjected to pure breeding was similar at ~33-34 %, but embryonic mortality was improved in eggs produced by Zimbabwean Blue males crossed to SA Black females (27 %. Embryonic mortality was increased in eggs that were set directly (32.0 % or subjected to longer than 6 days of storage (43.5 %. Embryonic mortality was affected by year. The results that were obtained will assist in determining non-infectious factors that have a negative

  9. Changes of Protein and Lipid Contents, Amino Acid and Fatty Acid Compositions in Eggs and Yolk-Sac Larvae of American Shad ( Alosa sapidissima)

    Science.gov (United States)

    Liu, Zhifeng; Gao, Xiaoqiang; Yu, Jiuxiang; Wang, Yaohui; Guo, Zhenglong; Huang, Bin; Liu, Baoliang; Hong, Lei

    2018-04-01

    To investigate the changes of the biochemical composition of American shad ( Alosa sapidissima) eggs and larvae at embryonic and early larval stages, samples were collected at different development stages from artificial fertilization to the end of yolk absorption including 2 h, 12 h and 30 h after fertilization and newly hatched larvae including 1 and 3 days after hatching. The composition of lipid, fatty acids, protein and amino acids were analyzed. The content of total protein exhibited a decreasing trend during embryogenesis and larval development, and a significant reduction was detected after hatching ( P acids after hatching except for glycine ( P fatty acids remained stable during the period of embryogenesis. But after hatching, a significant decrease was found in the content of C18:2n-6, C18:3n-6, SFA and ratio of EPA/ARA ( P acids.

  10. ROLE OF THE EGG JELLY COAT IN PROTECTING HYLA REGILLA AND BUFO CANORUS EMBRYOS FROM ULTRAVIOLET B RADIATION DURING DEVELOPMENT

    Science.gov (United States)

    Previous studies have suggested that Ultraviolet B (UVB) radiation may play a role in amphibian population declines. Some of these studies also indicate that egg hatching success is unaltered in some species of anurans as a result of UVB exposure. It has been proposed that the eg...

  11. Fungus gardens of the leafcutter ant Atta colombica function as egg nurseries for the snake Leptodeira annulata

    DEFF Research Database (Denmark)

    Baer, Boris; Den Boer, Susanne Petronella A; Kronauer, Daniel

    2009-01-01

    by ant soldiers and that also newly hatched snakes manage to avoid ant attacks when they leaving their host colony. We speculate that L. annulata might use Atta and Acromyrmex leafcutter ant colonies as egg nurseries by some form of chemical insignificance, but more work is needed to understand...

  12. Egg size and laying order in relation to offspring sex in the extreme sexually size dimorphic brown songlark, Cinclorhamphus cruralis

    NARCIS (Netherlands)

    Magrath, MJL; Komdeur, J; Dickinson, J.

    In some bird species, mothers can advantage the offspring of one sex either by elevating them in the laying order to promote earlier hatching or by allocating greater resources to eggs of the preferred sex. In size dimorphic species, the predictions as to which sex should benefit most from such

  13. Investigating the embryo/larval toxic and genotoxic effects of {gamma} irradiation on zebrafish eggs

    Energy Technology Data Exchange (ETDEWEB)

    Simon, O., E-mail: olivier.simon@irsn.fr [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 186, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Massarin, S. [Laboratoire de Modelisation Environnementale, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 159, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Coppin, F. [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 186, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Hinton, T.G. [Service d' Etude du Comportement des Radionucleides dans les Ecosystemes, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 159, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Gilbin, R. [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 186, BP3, 13115 Saint-Paul-lez-Durance Cedex (France)

    2011-11-15

    Eggs/larval of freshwater fish (Danio rerio) were exposed to low dose rates of external gamma radiation (from 1 to 1000 mGy d{sup -1}) over a 20-day period, with the objective of testing the appropriateness of the 10 mGy d{sup -1} guideline suggested by the IAEA. The present study examines different endpoints, mortality and hatching time and success of embryos as well as the genotoxicity of {gamma}-irradiations (after 48 h). The 20-day embryo-larval bioassay showed an enhanced larval resistance to starvation after chronic exposure to {gamma} irradiation (from low 1 mGy d{sup -1} to high dose rate 1000 mGy d{sup -1}) and an acceleration in hatching time. Gamma irradiation led to increased genotoxic damage Ito zebrafish egg (40-50% DNA in tail in Comet assay) from the lowest dose rate (1 mGy d{sup -1}). Possible mechanisms of {gamma} radiotoxicity and implications for radioprotection are discussed. - Highlights: > Relevant information on the {gamma} radiation impact on early life stage biota is scarce. > The eggs of zebrafish Danio rerio were selected as biological model. > We test the appropriateness of the 10 mGy d{sup -1} guideline (IAEA). > We observed effects measured at individual levels (starvation, hatching time). > Chronic gamma irradiation led to increased genotoxic damage to zebrafish egg. > {gamma} radiotoxicity mechanisms and implications for radioprotection are discussed.

  14. Effects of temperature on the life-history traits of Sancassania (Caloglyphus) berlesei (Acari: Astigmatina: Acaridae) feeding on root-knot nematodes, Meloidogyne spp. (Nematoda: Meloidogynidae).

    Science.gov (United States)

    Abou El-Atta, Doaa Abd El-Maksoud; Ghazy, Noureldin Abuelfadl; Osman, Mohamed Ali

    2014-11-01

    Sancassania (Caloglyphus) berlesei (Michael) is a cosmopolitan and free-living mite that inhabits soil as well as laboratory colonies of insects and fungi and may have a role as a biocontrol agent of nematodes. In this study, we investigated the effects of temperature on the development, reproduction, and food consumption of S. berlesei fed egg masses of root-knot nematodes, Meloidogyne spp., an important group of agricultural pests. Mites were reared at 20, 25 or 30 °C in the dark. The mites could feed on the nematode egg masses, and their developmental time decreased at higher temperatures. Time from the egg to adult was similar in females and males reared at the same temperature. Adult females lived longer than males at 25 °C, but not at 20 or 30 °C. Generally, females showed a higher rate of food consumption than males. Females laid the largest number of eggs at 20 and 25 °C (199.7 and 189.8 eggs/female, respectively), but the intrinsic rate of natural increase was highest at 30 °C (r m = 0.29). In comparing our data with previous reports, we noted that S. berlesei that fed on egg masses of root-knot nematodes showed a longer developmental time and a lower reproductive rate than Sancassania mites that fed on other diets. Nonetheless, the relatively high value of r m (e.g., at 25 and 30 °C) suggests that this mite may have certain advantages as a biocontrol agent of root-knot nematodes.

  15. Toxocara nematodes in stray cats from shiraz, southern iran: intensity of infection and molecular identification of the isolates.

    Directory of Open Access Journals (Sweden)

    Fattaneh Mikaeili

    2013-12-01

    Full Text Available Toxocara is a common nematode of cats in different parts of Iran. Despite the close association of cats with human, no attempt has been done so far for molecular identification of this nematode in the country. Therefore, current study was performed on identification of some isolates of Toxocara from stray cats in Shiraz, Fars Province, Southern Iran, based on morphological and molecular approaches, and also determination of intensity of infection.This cross-sectional study was carried out on 30 stray cats trapped from different geographical areas of Shiraz in 2011. Adult male and female worms were recovered from digestive tract after dissection of cats. Morphological features using existing keys and PCR-sequencing of ITS-rDNA region and pcox1 mitochondrial l gene were applied for the delineating the species of the parasites.Eight out of 30 cats (26.7% were found infected with Toxocara nematodes. All the isolates were confirmed as Toxocara cati based on morphological features and the sequence of ribosomal and mitochondrial targets. Intensity of infection ranged from one to a maximum of 39 worms per cat, with a mean of 10.25±12.36, and higher abundance of female nematodes.The most prevalent ascaridoid nematode of stray cats in the study area was T. cati and female nematodes were more abundant than that of males. This issue has important role in spreading of eggs in the environment and impact on human toxocariasis.

  16. Animal welfare and eggs

    DEFF Research Database (Denmark)

    Andersen, Laura Mørch

    and private good attributes of different types of eggs. We find that the estimated correlations are consistent with the levels of animal welfare, and that consumers perceiving a stronger connection between animal welfare and the organic label have higher willingness to pay for organic eggs, even when we...

  17. Egg Bungee Jump!

    Science.gov (United States)

    Fitzgerald, Mike; Brand, Lance

    2004-01-01

    In this article, the authors present an egg bungee jumping activity. This activity introduces students to ways that engineers might apply calculations of failure to meet a challenge. Students are required to use common, everyday materials such as rubber bands, string, plastic bags, and eggs. They will apply technological problem solving, material…

  18. Spinning Eggs and Ballerinas

    Science.gov (United States)

    Cross, Rod

    2013-01-01

    Measurements are presented on the rise of a spinning egg. It was found that the spin, the angular momentum and the kinetic energy all decrease as the egg rises, unlike the case of a ballerina who can increase her spin and kinetic energy by reducing her moment of inertia. The observed effects can be explained, in part, in terms of rolling friction…

  19. Effects of adult stocking density on egg production and viability in cultures of the calanoid copepod Acartia tonsa (Dana)

    DEFF Research Database (Denmark)

    Jepsen, Per Meyer; Andersen, Nikolaj; Holm, Thue

    2007-01-01

    was 84.7±4.8% and was never observed below 76.1%, with no significant differences across the stocking densities. Conclusively, as a practical recommendation for the aquaculture industry, copepod cultures with densities ranging from 100 to 600 adults L−1 and presumably even more dense cultures......The effect of stocking density of the calanoid copepod Acartia tonsa was evaluated in a 96 h rearing experiment. Possible density-dependent egg production and egg viability were analysed at stocking densities of 100, 200, 300, 400 and 600 adults L−1. Temperature, oxygen saturation and algal...... concentration were kept optimal. A non-density-dependent mortality rate of 15–19% day−1 was documented. A non-significant density-dependent egg production was observed between 100 and 600 adults L−1. The average egg production was 22.5±8.8 egg female−1 day−1 in all densities. The average egg hatching success...

  20. Cyst quality and hatching in parthenogenetic brine shrimp, Artemia

    Digital Repository Service at National Institute of Oceanography (India)

    Royan, J.P.; Sumitra-Vijayaraghavan; Krishnakumari, L.; Ramaiah, N.

    ) enhance the percentage of hatching of the cysts. On the basis of naupliar size, low ash content and high protein content it can be suggested that this strain is likely to be preferred by predators...

  1. Development and reproductive potential of Tyrophagus putrescentiae (Acari: Acaridae) on plant-parasitic nematodes and artificial diets.

    Science.gov (United States)

    Abou El-Atta, Doaa Abd El-Maksoud; Osman, Mohamed Ali

    2016-04-01

    This study investigated development, reproduction and life table parameters of the astigmatid mold mite Tyrophagus putrescentiae (Schrank) (Acari: Acaridae) feeding on egg-masses or adult females of the nematode Meloidogyne incognita, egg-masses of the nematode Rotylenchulus reniformis, ras cheese or yeast at 25 ± 1 °C, 70 ± 10 % RH in the dark. Immature developmental times were shorter when the mite was fed females of M. incognita followed by yeast. Different prey/diet types had no significant effect on longevity and lifespan of both males and females. Daily oviposition rate (eggs/female/day) was highest for mites fed yeast (20.8 ± 1.8 eggs) and lowest for mites fed females of M. incognita (6.6 ± 0.5). Intrinsic rate of natural increase (r m) was highest for mites fed yeast compared to other prey/diet; no significant differences in r m were observed among mites fed on non-yeast diets. This result may suggest a role of T. putrescentiae as biocontrol agent of plant-parasitic nematodes and the yeast may be used for mite mass-production purposes.

  2. Effects of in ovo feeding of cationic amino acids on hatchability, hatch weights, and organ developments in domestic pigeon squabs (Columba livia).

    Science.gov (United States)

    Zhang, X Y; Li, L L; Miao, L P; Zhang, N N; Zou, X T

    2018-01-01

    This study was conducted to evaluate the effect of in ovo feeding of cationic amino acids on hatchability, hatch weights, and organ developments in pigeon squabs. Two experiments were conducted in this study. Eggs in Exp. 1 were subjected to modification of in ovo feeding in pigeons. Optimal time was determined by checking amniotic fluid volume, and suitable length was confirmed through ink injection. Results showed that the optimum time of in ovo feeding was on d 13 of embryonic development, and the suitable injected length was 20 mm to reach the amniotic cavity of the embryo. Eggs in Exp. 2 were transferred to access in ovo feeding of cationic amino acids. A total of 75 fertile pigeon eggs was randomly distributed into 5 treatments of 15 replicate eggs. Treatments in Exp. 2 consisted of non-injected controls (Control), a sterile buffered solution (0.75% saline), or a cationic amino acid mixture (> 98.5% purity crystalline L-arginine, > 98% purity crystalline L-lysine, and > 98.5% purity L-histidine) containing 0.1, 1, or 10% concentration (Conc.), which were relative to their total content in the eggs, respectively. The crystalline amino acids were dissolved in 200 μL buffered solution prior to in ovo feeding. After hatching, hatch weight (HW) and organ weight (OW) of the squabs were measured immediately. In ovo feeding of cationic amino acids increased the proportions of yolk-free hatch weight to hatch weight (YFHW/HW) (quadratic P = 0.01), and those of OW to YFHW including the heart (quadratic P = 0.01), kidney (quadratic P < 0.01), and liver (quadratic P = 0.02) compared to the control group, and the levels of those ratios were maximized in the 1% Conc group. Also, a proportion of small intestine weight to YFHW improved (linear P = 0.02, quadratic P = 0.05) after in ovo feeding. The organ weight of the head, leg, heart, lung, kidney, proventriculus, pancreas, liver, and small intestine correlated with YFHW positively (0.4 < correlation coefficient < 0

  3. Egg size and offspring quality: a meta-analysis in birds.

    Science.gov (United States)

    Krist, Miloš

    2011-08-01

    Parents affect offspring fitness by propagule size and quality, selection of oviposition site, quality of incubation, feeding of dependent young, and their defence against predators and parasites. Despite many case studies on each of these topics, this knowledge has not been rigorously integrated into individual parental care traits for any taxon. Consequently, we lack a comprehensive, quantitative assessment of how parental care modifies offspring phenotypes. This meta-analysis of 283 studies with 1805 correlations between egg size and offspring quality in birds is intended to fill this gap. The large sample size enabled testing of how the magnitude of the relationship between egg size and offspring quality depends on a number of variables. Egg size was positively related to nearly all studied offspring traits across all stages of the offspring life cycle. Not surprisingly, the relationship was strongest at hatching but persisted until the post-fledging stage. Morphological traits were the most closely related to egg size but significant relationships were also found with hatching success, chick survival, and growth rate. Non-significant effect sizes were found for egg fertility, chick immunity, behaviour, and life-history or sexual traits. Effect size did not depend on whether chicks were raised by their natural parents or were cross-fostered to other territories. Effect size did not depend on species-specific traits such as developmental mode, clutch size, and relative size of the egg, but was larger if tested in captive compared to wild populations and between rather than within broods. In sum, published studies support the view that egg size affects juvenile survival. There are very few studies that tested the relationship between egg size and the fecundity component of offspring fitness, and no studies on offspring survival as adults or on global fitness. More data are also needed for the relationships between egg size and offspring behavioural and

  4. EGG: Empirical Galaxy Generator

    Science.gov (United States)

    Schreiber, C.; Elbaz, D.; Pannella, M.; Merlin, E.; Castellano, M.; Fontana, A.; Bourne, N.; Boutsia, K.; Cullen, F.; Dunlop, J.; Ferguson, H. C.; Michałowski, M. J.; Okumura, K.; Santini, P.; Shu, X. W.; Wang, T.; White, C.

    2018-04-01

    The Empirical Galaxy Generator (EGG) generates fake galaxy catalogs and images with realistic positions, morphologies and fluxes from the far-ultraviolet to the far-infrared. The catalogs are generated by egg-gencat and stored in binary FITS tables (column oriented). Another program, egg-2skymaker, is used to convert the generated catalog into ASCII tables suitable for ingestion by SkyMaker (ascl:1010.066) to produce realistic high resolution images (e.g., Hubble-like), while egg-gennoise and egg-genmap can be used to generate the low resolution images (e.g., Herschel-like). These tools can be used to test source extraction codes, or to evaluate the reliability of any map-based science (stacking, dropout identification, etc.).

  5. Development of space-fertilized eggs and formation of primordial germ cells in the embryos of medaka fish

    Science.gov (United States)

    Ijiri, K.

    In the second International Microgravity Laboratory (IML-2) mission in 1994, four small Japanese killifish (Medaka, Oryzias latipes) made a space travel of 15 days aboard a space shuttle. These four adult Medaka fish successfully mated in space for the first time among vertebrate animals. Moreover, the eggs they laid developed normally, at least in their external appearance, hatching as fry (baby fish) in space. Fish mated and laid eggs every day during the first week. Near the end of the mission most of the eggs had a well-developed body with two pigmented eyes. In total, 43 eggs were laid (detected), out of which 8 fry hatched in space, as truly `space-originated' babies. A further 30 fry hatched within 3 days after landing. This is the normal hatching rate, compared with the ground-based data. Among the 8 space-originated fry, four were killed for histological sections, and germ cells at the gonadal region were counted for each fry. Their numbers were in the range of the germ cells of the normal control fry (ground-kept samples). Thus, as embryos developed normally in their external appearance, inside the embryos the formation of primordial germ cells took place normally in space, and their migration to the genital ridges was not hindered by microgravity. The two of the remaining space-originated fry have grown up and been creating their offspring in the laboratory. This proved that the primordial germ cells formed in space were also normal from a functional point of view. The four space-travelled adult fish re-started mating and laying eggs on the 7th day after landing and continued to do so every day afterward. Fertilization rate and hatchability of these eggs were as high as the eggs laid by the laboratory-kept fish. This fact implies that in gametogenesis of adult fish, there are no specific stages of germ cells extremely susceptible to microgravity.

  6. The effect of chronic exposure to 238Pu(IV) citrate on the embryonic development of carp and fathead minnow eggs

    International Nuclear Information System (INIS)

    Till, J.E.

    1978-01-01

    This study focused on the effects of plutonium to the developing fish egg. A quantitative analysis of the uptake of 238 Pu(IV) citrate by carp eggs indicated that plutonium is accumulated in the egg and reaches a concentration factor of approx 4 at hatching (72hr after exposure begins). Autoradiographs made from carp eggs that had been exposed to 238 Pu revealed that, although some plutonium was concentrated on the egg chorion, plutonium that penetrated the chorion was uniformly distri-buted throughout the perivitelline fluid, embryo and yolk sac. Using the uptake data for carp eggs, dose conversion factors were calculated for both carp eggs and fathead minnow eggs exposed to 238 Pu during embryological development. These values were 2100 rad/μCi/ml and 7500 rad/μCi/ml for carp and fathead minnows, respectively. Experiments were conducted in which both carp and fathead minnow eggs were exposed to plutonium in solution during embryogenesis; the percentage of eggs hatching, the number of abnormal larvae produced, and the survival of larvae were used as indicators of radiation toxicity. Concentrations in excess of 1 μCi/ml were required to prevent both species of eggs from hatching. It is concluded that fish eggs developing in natural aquatic ecosystems contaminated with plutonium probably do not receive a significant dose from the plutonium alpha radioactivity. Future analysis of fecundity and the production of abnormalities in the offspring of larvae exposed during embryological development would provide an additional degree of sensitivity to the toxicity test system used in this study. (author)

  7. Immunoglobulins in the eggs of the nurse shark, Ginglymostoma cirratum.

    Science.gov (United States)

    Haines, Ashley N; Flajnik, Martin F; Rumfelt, Lynn L; Wourms, John P

    2005-01-01

    Elasmobranchs, which include the sharks, skates, and rays, emerged over 450 million years ago and are the oldest vertebrates to possess an adaptive immune system. They have evolved diverse reproductive modes, with a variety of physiological adaptations that enhance reproductive success. The nurse shark, Ginglymostoma cirratum, is an aplacental, viviparous elasmobranch in which the egg and its associated vitelline vasculature are the primary route for maternal-embryonic interactions. During gestation, nurse shark embryos hatch from their eggcases and develop free in the uterus, which is flushed regularly with seawater. Similar to higher vertebrates, embryonic and neonatal nurse sharks possess an immune system that is not fully competent. In birds and bony fishes, maternal immunoglobulins (Ig) stored in the egg during oogenesis confer protective immunity to embryos during gestation. However, early research suggested that such transfer of passive immunity does not occur in sharks. To better understand how elasmobranch embryos are protected from waterborne pathogens during this potentially vulnerable time, we have re-examined the existence of Igs in elasmobranch eggs. Using monoclonal antibodies, we establish the presence of two classes of Igs in nurse shark eggs: 7S IgM and IgNAR. The potential transfer of immunoglobulins from elasmobranch eggs is discussed.

  8. A laboratory investigation of the suspension, transport, and settling of silver carp eggs using synthetic surrogates

    Science.gov (United States)

    Garcia, Tatiana; Zuniga Zamalloa, Carlo; Jackson, P. Ryan; Murphy, Elizabeth A.; Garcia, Marcelo H.

    2015-01-01

    Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter) as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this research study

  9. A Laboratory Investigation of the Suspension, Transport, and Settling of Silver Carp Eggs Using Synthetic Surrogates.

    Directory of Open Access Journals (Sweden)

    Tatiana Garcia

    Full Text Available Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this

  10. A Laboratory Investigation of the Suspension, Transport, and Settling of Silver Carp Eggs Using Synthetic Surrogates.

    Science.gov (United States)

    Garcia, Tatiana; Zuniga Zamalloa, Carlo; Jackson, P Ryan; Murphy, Elizabeth A; Garcia, Marcelo H

    2015-01-01

    Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter) as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this research study

  11. A Laboratory Investigation of the Suspension, Transport, and Settling of Silver Carp Eggs Using Synthetic Surrogates

    Science.gov (United States)

    Garcia, Tatiana; Zuniga Zamalloa, Carlo; Jackson, P. Ryan; Murphy, Elizabeth A.; Garcia, Marcelo H.

    2015-01-01

    Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter) as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this research study

  12. Accuracy of egg flotation throughout incubation to determine embryo age and incubation day in water bird nests

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2010-01-01

    Floating bird eggs to estimate their age is a widely used technique, but few studies have examined its accuracy throughout incubation. We assessed egg flotation for estimating hatch date, day of incubation, and the embryo's developmental age in eggs of the American Avocet (Recurvirostra americana), Black-necked Stilt (Himantopus mexicanus), and Forster's Tern (Sterna forsteri). Predicted hatch dates based on egg flotation during our first visit to a nest were highly correlated with actual hatch dates (r = 0.99) and accurate within 2.3 ?? 1.7 (SD) days. Age estimates based on flotation were correlated with both day of incubation (r = 0.96) and the embryo's developmental age (r = 0.86) and accurate within 1.3 ?? 1.6 days and 1.9 ?? 1.6 days, respectively. However, the technique's accuracy varied substantially throughout incubation. Flotation overestimated the embryo's developmental age between 3 and 9 days, underestimated age between 12 and 21 days, and was most accurate between 0 and 3 days and 9 and 12 days. Age estimates based on egg flotation were generally accurate within 3 days until day 15 but later in incubation were biased progressively lower. Egg flotation was inaccurate and overestimated embryo age in abandoned nests (mean error: 7.5 ?? 6.0 days). The embryo's developmental age and day of incubation were highly correlated (r = 0.94), differed by 2.1 ?? 1.6 days, and resulted in similar assessments of the egg-flotation technique. Floating every egg in the clutch and refloating eggs at subsequent visits to a nest can refine age estimates. ?? The Cooper Ornithological Society 2010.

  13. Radionuclides in Canada goose eggs

    International Nuclear Information System (INIS)

    Rickard, W.H.; Sweany, H.A.

    1975-01-01

    Low levels of radionuclides were measured in Canada goose eggs taken from deserted nests from Columbia River islands on the Energy Research and Development Administration's Hanford Reservation. Potassium-40, a naturally occurring radionuclide, was the most abundant radionuclide measured in egg contents and egg shell. Strontium-90 was incorporated into egg shells and cesium-137 into inner egg contents. Manganese-54, cobalt-60, and zinc-65 were more abundant in inner egg contents than in egg shell. Cerium-144 was detected in egg shell but not in inner shell

  14. Snapping turtles (Chelydra serpentina) as bioindicators in Canadian areas of concern in the Great Lakes Basin. II. Changes in hatching success and hatchling deformities in relation to persistent organic pollutants.

    Science.gov (United States)

    de Solla, S R; Fernie, K J; Ashpole, S

    2008-06-01

    Hatching success and deformities in snapping turtle hatchlings (Chelydra serpentina) were evaluated using eggs collected from 14 sites in the Canadian lower Great Lakes, including Areas of Concern (AOC), between 2001 and 2004. Eggs were analyzed for PCBs, PBDEs, and pesticides. Between 2002 and 2004, hatchling deformity rates were highest in two AOCs (18.3-28.3%) compared to the reference sites (5.3-11.3%). Hatching success was poorest in three AOCs (71.3-73.1%) compared to the reference sites (86.0-92.7%). Hatching success and deformity rates were generally poorer in 2001 compared to 2002-2004, irrespective of the study location and could be due to egg handling stress in 2001. Hatching success and deformities were generally worst from the Wheatley Harbour, St. Lawrence River (Cornwall), Detroit River, and Hamilton Harbour AOCs. Associations between contaminant burdens with embryonic development were sufficiently poor that the biological relevance is questionable. Stressors not measured may have contributed to development abnormalities.

  15. Context-Dependent Plastic Response during Egg-Laying in a Widespread Newt Species.

    Directory of Open Access Journals (Sweden)

    Zoltán Tóth

    Full Text Available Previous research on predator-induced phenotypic plasticity mostly focused on responses in morphology, developmental time and/or behaviour during early life stages, but the potential significance of anticipatory parental responses has been investigated less often. In this study I examined behavioural and maternal responses of gravid female smooth newts, Lissotriton vulgaris, in the presence of chemical cues originating from invertebrate predators, Acilius sulcatus water beetles and Aeshna cyanea dragonfly larvae. More specifically, I tested the extent of oviposition preference, plasticity in egg-wrapping behaviour and plasticity in egg size when females had the possibility to lay eggs at oviposition sites with and without predator cues during overnight trials. I found that individuals did not avoid laying eggs in the environment with predator cues; however, individuals that deposited eggs into both environments adjusted the size of the laid eggs to the perceived environment. Females deposited larger eggs earlier in the season but egg size decreased with time in the absence of predator cues, whereas individuals laid eggs of average size throughout the investigated reproductive period when such cues were present. Also, egg size was found to be positively related to hatching success. Individuals did not adjust their wrapping behaviour to the presence of predator cues, but females differed in the extent of egg-wrapping between ponds. Females' body mass and tail depth were also different between ponds, whereas their body size was positively associated with egg size. According to these results, female smooth newts have the potential to exhibit activational plasticity and invest differently into eggs depending on temporal and environmental factors. Such an anticipatory response may contribute to the success of this caudate species under a wide range of predator regimes at its natural breeding habitats.

  16. Energy utilization and heat production of embryos from eggs originating from young and old broiler breeder flocks.

    Science.gov (United States)

    Nangsuay, A; Meijerhof, R; Ruangpanit, Y; Kemp, B; van den Brand, H

    2013-02-01

    Two experiments were conducted to study the interaction between breeder age and egg size on the energy utilization (experiment 1) and heat production (experiment 2) of broiler embryos. In experiment 1, a total of 4,800 Ross-308 hatching eggs from 2 breeder ages (29 and 53 wk of age, or young and old) and, within each age, 2 egg sizes (57 to 61 g and 66 to 70 g, or small and large) were used. In experiment 2, a total of 240 Ross-308 hatching eggs from 2 breeder flocks at 29 (young) and 53 (old) wk of age, and which were selected from the same egg weight range (58 to 61 g), were tested in 2 replicate chambers. In experiment 1, it was shown that the amount of yolk relative to albumen was higher in the old flock eggs, and this effect was more pronounced in the large eggs. The old flock eggs, especially the larger egg size, contained more energy as a result of a greater yolk size. Energy utilization of the embryos was positively related to yolk size and the amount of energy transferred to yolk-free body (YFB) was largely determined by the available egg energy. The efficiency of converting egg energy into chick body energy (E(YFB)) was equal for both egg sizes and both breeder age groups. Chick YFB weight of young and old flock eggs was equal. However, dry YFB weight of chicks from old flock eggs was higher than in chicks from young flock eggs, which was associated with more protein and fat content and thus more energy accumulated into YFB. As a consequence, embryos derived from old flock eggs produced more heat from d 16 of incubation onward than those of the young flock eggs. In conclusion, the higher energy deposition into chick YFB of old flock eggs, leading to higher embryonic heat production, is the result of a higher amount of available energy in the egg and is not due to changes in E(YFB).

  17. Biocontrol: Fungal Parasites of Female Cyst Nematodes

    OpenAIRE

    Kerry, Brian

    1980-01-01

    Three species of fungi, Catenaria auxiliarls (Kühn) Tribe, Nematophthora gynophila Kerry and Crump, and a Lagenidiaceous fungus have been found attacking female cyst nematodes. All are zoosporic fungi which parasitize females on the root surface, cause the breakdown of the nematode cuticle, and prevent cyst formation. Their identification and some aspects of their biology are reviewed. N. gynophila is widespread in Britain and reduces populations of the cereal cyst nematode, Heterodera avenae...

  18. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds☆

    Science.gov (United States)

    Holm, Signe A.; Sörensen, Camilla R. L.; Thamsborg, Stig M.; Enemark, Heidi L.

    2014-01-01

    The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR) in 10 selected herds were investigated during April–September 2012. All Danish herds (n = 137) with 10 or more adult goats were invited to participate, and of these 27 herds met the inclusion criterion of more than 10 young kids never treated with anthelmintics. Questionnaire data on management were collected, and faecal samples from 252 kids were analysed by the McMaster technique. From all herds with a mean faecal egg count (FEC) above 300 eggs per g of faeces, pooled samples were stained with peanut agglutinin (PNA) for specific detection of Haemonchus contortus. Strongyle eggs were detected with an individual prevalence of 69%, including Nematodirus battus (3.6%) and other Nematodirus species (15.0%). Eimeria spp. were observed in 99.6% of the kids. H. contortus was found in 11 of 12 (92%) tested herds. Anthelmintics were used in 89% of the herds with mean treatment frequencies of 0.96 and 0.89 treatments per year for kids and adults, respectively. In 2011, new animals were introduced into 44% of the herds of which 25% practised quarantine anthelmintic treatments. In 10 herds the presence of AR was analysed by egg hatch assay and FEC reduction tests using ivermectin (0.3 mg/kg) or fenbendazole (10.0 mg/kg). AR against both fenbendazole and ivermectin was detected in seven herds; AR against fenbendazole in one herd, and AR against ivermectin in another herd. In conclusion, resistance to the most commonly used anthelmintics is widespread in larger goat herds throughout Denmark. PMID:25076056

  19. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds☆

    Directory of Open Access Journals (Sweden)

    Holm Signe A.

    2014-01-01

    Full Text Available The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR in 10 selected herds were investigated during April–September 2012. All Danish herds (n = 137 with 10 or more adult goats were invited to participate, and of these 27 herds met the inclusion criterion of more than 10 young kids never treated with anthelmintics. Questionnaire data on management were collected, and faecal samples from 252 kids were analysed by the McMaster technique. From all herds with a mean faecal egg count (FEC above 300 eggs per g of faeces, pooled samples were stained with peanut agglutinin (PNA for specific detection of Haemonchus contortus. Strongyle eggs were detected with an individual prevalence of 69%, including Nematodirus battus (3.6% and other Nematodirus species (15.0%. Eimeria spp. were observed in 99.6% of the kids. H. contortus was found in 11 of 12 (92% tested herds. Anthelmintics were used in 89% of the herds with mean treatment frequencies of 0.96 and 0.89 treatments per year for kids and adults, respectively. In 2011, new animals were introduced into 44% of the herds of which 25% practised quarantine anthelmintic treatments. In 10 herds the presence of AR was analysed by egg hatch assay and FEC reduction tests using ivermectin (0.3 mg/kg or fenbendazole (10.0 mg/kg. AR against both fenbendazole and ivermectin was detected in seven herds; AR against fenbendazole in one herd, and AR against ivermectin in another herd. In conclusion, resistance to the most commonly used anthelmintics is widespread in larger goat herds throughout Denmark.

  20. Nematode infections: soil-transmitted helminths and trichinella.

    Science.gov (United States)

    Knopp, Stefanie; Steinmann, Peter; Keiser, Jennifer; Utzinger, Jürg

    2012-06-01

    Infection with soil-transmitted helminths occurs via ingestion of nematode eggs with contaminated food and water, via hands, or inhalation of dust, or by penetration of larvae through the skin. Trichinella infections are caused by the ingestion of larvae contained in undercooked meat. In highly endemic areas, preventive chemotherapy (ie, regular administration of anthelmintic drugs to at-risk populations) is the key strategy against soil-transmitted helminthiasis. Integrated control approaches, including improved hygiene, sanitation, and water, are required for lasting effects. Because of growing tourism, travel, and migration, clinicians and specialized travel clinics must remain aware of the diagnosis, prevention, and treatment of soil-transmitted helminth and Trichinella infections. Copyright © 2012 Elsevier Inc. All rights reserved.