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1.
Tissue samples and feces were collected from a dead, adult female coyote (Canis latrans) found at the side of the road in late March 2003 in the Avalon Peninsula region of Newfoundland, Canada. The coyote apparently died of vehicular-related trauma. Samples of lung, brain, heart, liver, and kidney were fixed in formalin and submitted for histologic examination. The entire remaining lung and heart also were submitted for examination. The coyote was diagnosed with moderate, multifocal, granulomatous interstitial pneumonia with eosinophilic vasculitis and many intralesional nematode eggs, larvae, and occasional intravascular adult worms. Adult nematodes recovered from the pulmonary arteries were identified as Angiostrongylus vasorum. Small foci of granulomatous inflammation, often containing nematode eggs and larvae, were scattered in the brain and kidney. To our knowledge, this is the first report of A. vasorum infection in a coyote from the only endemic area of infection in North America.  相似文献   

2.
Muskoxen (Ovibos moschlatus moschatus) on the northwestern mainland of Nunavut and Northwest Territories, Canada, are infected with the protostrongylid lungworm, Umingmaksrongylus pallikuuhkensis. The geographic range of this muskox population is expanding to the south and west, and it is anticipated that these animals will eventually become sympatric with Dall's sheep (Ovis dalli dalli) in the Mackenzie and Richardson Mountains. To address the concern of wildlife managers that U. pallikulkensis may infect and adversely affect Dalls sheep, four Dalls/Stone's (Ovis dalli stonei) hybrid lambs and one adult muskox (Ovibos moschatus wardi) were each given 100 third-stage larvae of U. pallikuukensis. All animals were intensively monitored for 9 mo postinfection (PI) using clinical examinations, fecal analyses, hematology, blood chiemistry and medical imaging. No first-stage larvae of U. pallikuinkensis were recovered from the lambs and monitoring revealed nio evidence that the parasite had established in any of these animals. First-stage larvae were found in the feces of the muskox beginning at 94 days PI, and typical parasite cysts were visible in lung radiographs at 188 days PI. This study addresses an important management and wildlife health issue associated with the potential for host-switching of pathogens and indicates that it is improbable that thinhorn sheep are suitable hosts for U. pallikuukensis.  相似文献   

3.
Erwin TL  White WH 《ZooKeys》2012,(194):17-32
Adults and larvae of Leptotrachelus dorsalis (Fabricius), the Sugarcane Savior Beetle, live in association with grasses, the larvae in the appressed leaf axils. Both adult and larval Leptotrachelus dorsalis eat larvae of the Sugarcane Borer, Diatraea saccharalis (Fabricius), and perhaps other insects living in the confines of the leaf sheaths of that and other grass-like species. The geographic range of Leptotrachelus dorsalis extends from Kansas in the west to the Atlantic seaboard, north as far as Ontario, Canada and south to Cuba; it is an eastern species of North America and the Caribbean. Larval character attributes that are shared with a related ctenodactyline, Askalaphium depressum (Bates), provide a preliminary basis for characterization of the immatures of tribe Ctenodactylini.  相似文献   

4.
SUMMARY. Certain larvae and pupae have been identified as Notidobia ciliaris (Linné) by rearing field-collected larvae to the adult stage and by rearing larvae from eggs laid by a female in captivity. The larvae differ in many important respects from larvae of this species described by earlier workers. Characters are provided to distinguish these larvae and their associated pupae from those of Sericostoma personatum (Spence). The habitat and distribution of both species in Britain is outlined.  相似文献   

5.
This paper reports the role of darkling beetles Pimelia laevigata costipennis and Hegeter amaroides (Tenebrionidae) as intermediate hosts of spiruroid nematodes parasites of the black rat and house mouse of El Hierro (Canary Islands). Larvae of spiruroid species were found in the two tenebrionids (18.1% in P. l. costipennis, 7.8% in H. amaroides), Streptopharagus greenbergi being predominant in both (16.1% and 7.1%, respectively), ahead of Mastophorus muris and Gongylonema type larva. The larval stages of S. greenbergi are described for the first time, and adult worms were obtained experimentally from an infected laboratory rat, allowing the identification of the species. Morphometric measurements of experimental adults match those of adults detected in naturally infected rats on the island. Molecular data for S. greenbergi, and the ITS nucleotide sequence of the genus Streptopharagus are also provided for the first time. After the isolation of S. greenbergi DNA and amplification of the ITS region, the ITS1 of this spirocercid was sequenced and deposited in the GenBank database.  相似文献   

6.
首次描述了采自中国香港的短须滑爪蜉Cloeodes longisetosus(Braasch and Soldán)的成虫形态及重新描述了该种的稚虫形态.所有成虫标本由稚虫在实验室内饲养而成.对于短须滑爪蜉稚虫的研究进一步明确了该种在滑爪蜉属Cloeodes中的地位.短须滑爪蜉的稚虫与同属其它种类的主要区别是下颚须极短.短须滑爪蜉雄性成虫外生殖器的尾铗基部具有一块近长方形的突起,这一特征在同属其它已知成虫中是很独特的.这也表明类似这种特征在滑爪蜉属中也许存在或不存在.  相似文献   

7.
美丽青背姬小蜂生物学特性研究   总被引:4,自引:0,他引:4  
美丽青背姬小蜂Chrysonotomyiaformosa(Westwood)是美洲斑潜蝇的优势天敌,在美洲 斑潜蝇的自然控制中发挥着非常重要的作用。本文对其生物学进行了研究,结果表明:在实验 温度范围内,随着温度的升高,寄生蜂羽化趋早,羽化时间更集中,羽化高峰也更明显;随着 温度的升高,成蜂的寿命逐渐缩短。在提供清水时,寄主可以显著地延长雌蜂的寿命;在有寄 主时,提供10%蜂蜜水,雌蜂的寿命显著延长。美丽青背姬小蜂对3龄寄主幼虫有偏好,对3龄寄 主幼虫的致死率和寄生率都高于对1~2龄寄主幼虫的,且产下后代的雌雄性比为5.11∶1。在 实验温度范围内,发育历期随温度的升高而缩短。  相似文献   

8.
We described the carryover of Strelkovimermis spiculatus (Poinar and Camino) (Nematoda: Mermithidae) from mosquito larvae, the primary site of maturation, to adults. We analyzed the survival time of male and female Aedes albifasciatus (Macquart) (Diptera: Culicidae) parasitized by S. spiculatus, the time of emergence of nematodes from adult mosquitoes, and the state of parasitism in the same mosquito cohorts during the immature stages. Mosquito larvae with single and multiple parasitism (up to 11 parasites) were observed. The mortality of mosquito larvae and adults was produced in all cases where at least one mermithid emerged. The mortality of S. spiculatus showed an increasing trend in mosquito larvae with larger numbers of nematodes and was higher in larvae parasitized by eight or more nematodes. Maximum survival of parasitized adult females of Ae. albifasciatus was 38 days, while non‐parasitized adult males and females survived 39 and 41 days, respectively. Strelkovimermis spiculatus mortality was observed in Ae. albifasciatus larvae with single or multiple parasitisms. The spread of mermithid parasitism in adult mosquito populations is discussed.  相似文献   

9.
Abstract:  Life history parameters in two generations of endoparasitoid Campoletis chlorideae (Uchida) were examined using Bacillus thuringiensis (Bt)-resistant Helicoverpa armigera (Hübner) larvae feeding on B. thuringiensis toxin Cry1Ac. In the laboratory, Bt toxin was fed to Bt-resistant host larvae continuously in case of Bt treatment and only before or after the host larvae were parasitized in Bt–P and P–Bt treatments, respectively. C. chlorideae pupae developed faster in Bt treatment than non-Bt treatment. The shortened pupal stage duration was mainly because of the feeding of host larvae on Bt-diet before being parasitized. Body length of adult male C. chlorideae developed inside Bt-treated Bt-resistant (Bt–Bt) H. armigera larvae significantly decreased, especially in host larvae feeding on Bt-diet after being parasitized. However, survival, pupal mortality and adult longevity of C. chlorideae were almost unaffected in Bt-resistant H. armigera larvae feeding on Bt-toxin. Furthermore, Bt-treated host larvae had the same effect on the F1 progeny of C. chlorideae as the previous generation, and there was no significant difference between generations. This experiment suggests that there is very limited effect on the life history parameters in two generations of C. chlorideae parasitizing Bt–Bt H. armigera larvae. But both generations of C. chlorideae are affected when Bt-resistant H. armigera larvae fed on Bt toxin for different durations.  相似文献   

10.
In laboratory bioassays we tested the predatory capacity of the copepod Mesocyclops annulatus on Aedes aegypti and Culex pipiens larvae. A single adult female of M. annulatus caused 51.6% and 52.3% mortality of 50 first instar larvae of Ae. aegypti and Cx. pipiens respectively, in a 72 h test period. When alternative food was added to the containers, mortality rates declined to 16% and 10.3% for Ae. aegypti and Cx. pipiens respectively. When 50 first instar larvae of each of the two mosquito species tested were placed together with a single adult female of M. annulatus, mortality rates were 75.5% for Ae. aegypti larvae and 23.5% for Cx. pipiens larvae in a three day test period. Different density of adult females of M. annulatus ranged from 5 to 25 females produced mortality rates of Ae. aegypti first instar larvae from 50% to 100% respectively. When a single adult female of M. annulatus was exposed to an increasing number of first-instar Ae. aegypti larvae ranging from 10 to 100, 100% mortality was recorded from 1 to 25 larvae, then mortality declined to 30% with 100 larvae. The average larvae killed per 24 h period by a single copepod were 29.  相似文献   

11.
Parameters related to the occurrence, aggregation, and population structure of the nematode Contracaecum rudolphii Hartwich, 1964 , in the great cormorant ( Phalacrocorax carbo ) from northeastern Poland were analyzed. A total of 491 birds of different ages (adults, immatures, and nestlings) was examined; the cormorants studied were taken from both fresh- and brackish water habitats. Contracaecum rudolphii were found in stomachs of 454 birds (92.5%); the 46,244 nematodes included third- (L3) and fourth-stage larvae (L4), and sub-adult and adult females and males. The distribution of nematodes in the host population were highly aggregated. The occurrence of C. rudolphii was significantly dependent on the host's age and habitat, as well as on season; the proportion of development stages differed significantly depending on birds' age and season (the latter only in adult birds). The infrapopulations of C. rudolphii in the adult cormorants showed distinct density-dependent correlations: that is, as the infrapopulation size increased, the number of adult females C. rudolphii decreased, and the proportion of larvae and sub-adult females increased. A higher proportion of larvae and sub-adult females characterized the component population structure of the nematodes in the cormorant nestlings, compared with adult birds, probably because of immune system deficiency in the immature birds, coupled with the development of the nematode population. Seasonal changes in the C. rudolphii population, observed in the adult cormorants, were not related to seasonality of the L3 occurrence in food; instead, the changes are believed to have resulted from independent processes of elimination of the oldest nematodes and their replacement by larval stages that subsequently matured.  相似文献   

12.
Summary The salivary gland nuclei of larvalGlyptotendipes barbipes from Stratford (Ontario) comprise 3 pairs of long metacentric chromosomes (I–III) and one pair of short acrocentrics (IV). Homologues are closely paired when homozygous, centromeres are expressed as heterochromatic drums. Each chromosome carries a nucleolus, and Chromosome IV in addition carries a Ring of Balbiani. The gross polytene idiogram is identical with that implicit inBauer's cytological analysis of the same species from Germany.In direct comparison the banding pattern of the German and Canadian larvae proved identical for at least one sequence in each chromosome arm.Three simple inversions are known in the species; one (III L-1) is endemic to Germany, a second (II L-3) has been found only once in Canada and a third (I S-1) is common in Canada but has not been reported from Germany. The remaining 2 inversions (II L-1,2 and III S-1,2) are complex and are here analysed as included types. Rearrangement II L-1,2 occurs both in Canada and in Germany and achieves heterozygous frequencies near 50% in both countries. It is the first inversion reported to be holarctic in distribution in insects not associated with man. The second complex inversion III S-1,2 has been found only in Canada where it is common. In each of the complex inversions at least one pair of breaks is near coincident.Meiosis is normal and chiasmatic in structurally homozygous males. It lacks conspicuous localization of chiasmata. No meiotic abnormalities were observed in inversion heterozygotes. It is postulated that complex heterozygous inversions interfere with pairing to such an extent that the residual ill-effects are out balanced by heterosis of co-adapted systems.A selective advantage of heterozygosis is directly indicated for II L by a significant (p=0.02) excess of II L/II L-1,2 larvae over the Hardy-Weinberg expectation.  相似文献   

13.
Dakota skipper (Hesperia dacotae Skinner) and Poweshiek skipperling (Oarisma poweshiek Parker) (Lepidoptera: Hesperiidae) are endemic prairie species that are threatened in Canada. Surveys during the brief adult flight period are necessary to quantify population sizes, but dates of adult emergence vary widely from year to year (up to 24 days) and populations are geographically distant from one another (150–250 km). To predict adult emergence of H. dacotae and O. poweshiek, we used local weather station data to calculate the number of degree days accumulated between March 1 and adult emergence using two different models in seven different years between 2002 and 2013. We also compared the number of degree days accumulated at the soil surface where larvae and pupae reside to those accumulated using weather station data. We recommend that surveys for Dakota skipper begin when degree day accumulations (from weather stations) reach a threshold of 575 (standard model) or 600 (double sine model) in the south central portion of Manitoba and 550 (standard model) or 575 (double sine model) in the southwest region of Manitoba. For Poweshiek skipperling surveys should be considered after degree day accumulations reach 575 (standard model) or 625 (double sine model). Degree days accumulated at the soil surface were 20–30 % greater than those calculated using weather station data in Dakota skipper sites, and 1–12 % greater in Poweshiek skipperling sites. Using our models, we predicted adult emergence to within 48 h of emergence in 2011, 2012 and 2013.  相似文献   

14.
We examined the escape behavior of larvae and postlarvae of the American lobster (Homarus americanus) and of adult immature (stage ADI) crayfish (Cherax destructor). Responses to standardized water jet stimuli delivered through a pipette were observed and analyzed. Lobster larvae did not respond to stimuli within 60 ms, indicating that they do not have functional giant fibers. The first movement by lobster larvae in response to water jet stimuli was a hyperextension of the abdomen. Larval escape responses also showed very little habituation. Postlarval lobsters and ADI crayfish showed the same range of responses as adult animals. Displacement efficiency of tailflicks exhibited by the different animals and stages was examined and related to the morphology of the animals. A separate behavior from tailflicking by larval lobsters in response to water jet stimuli was also observed. Here, the abdomen was hyperextended and the thoracic appendages were promoted. We termed this behavior a "starburst" response. The features of the tailflicking behavior suggest that it evolved to make the larvae difficult prey to handle for small, slower moving predators, and possibly to allow them to ride the bow waves of faster moving predators.  相似文献   

15.
Red imported fire ant, Solenopsis invicta, colonies were infected horizontally by introducing live brood (mainly larvae and pupae) infected with Thelohania solenopsae. Live, infected brood introduced into uninfected colonies were adopted and raised to adulthood instead of being executed by the recipient colony. Introductions of infected larvae with uninfected pupae, which eclose into adult worker caste fire ants, resulted in an 80% infection rate of the inoculated colonies. Infections from introductions of infected pupae with uninfected larvae resulted in a 37.5% infection of inoculated colonies. Infections were also detected in 11.6 and 3.7% of the adult worker caste ants that eclosed from uninfected large larvae and pupae, respectively, that were held with infected adult workers. Microscopic examination of infected brood revealed sporoblasts and large numbers of spores of T. solenopsae in S. invicta pupae.  相似文献   

16.
In organisms lacking parental care or when eggs of more than one female are layed together, parents preferentially tend to avoid eating their own offspring. In some species of newts (Caudata: Salamandridae), there is no parental care and cannibalism of eggs and larvae occurs when philopatric adults remain in the pond throughout the breeding season where eggs and larvae develop. Kin discrimination by both adult newts and larvae would be expected to occur during the breeding season as it would enable individuals to benefit from the nutrients obtained from eating eggs and larvae while they avoid eating close relatives. The effects of kinship on cannibalism of eggs and larvae were examined in two species of newts. In separate, but similar, paired behavioral trials adult female red-spotted newts, Notophthalmus viridescens, and smooth newts, Triturus vulgaris, were allowed to consume their own egg or an egg from another female. Female red-spotted newts, but not smooth newts, preferred to eat eggs of other females rather than their own, and overall smooth newts were ‘reluctant’ to eat conspecific eggs. To test for ontogenetic shifts in discrimination abilities, additional experiments were performed with adult female red-spotted newts paired with their own larvae and a larva from another female. In addition, the effects of kinship on the attraction or repulsion of larvae was also studied in red-spotted newts. Females showed no significant discrimination abilities during acts of cannibalism on larvae. Larvae spent similar amounts of time with siblings and non-siblings. These results suggest that the ability of adult newts to discriminate among eggs varies between species and that the elicitation of a kin-discrimination response may be context-dependent. For red-spotted newts, there was no evidence of discrimination abilities within and between other life-history stages.  相似文献   

17.
We evaluated the effects of X-ray irradiation on larvae of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), with the aim of finding a treatment that prevented adult fly emergence, yet did not adversely affect larval quality as rearing hosts for the parasitoid Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Ichneumonidae). Two experiments were carried out. In the first experiment, small numbers of larvae were held in Petri dishes with and without small amounts of rearing media and then irradiated with doses of X-rays ranging from 0 to 8333.6 R (equivalent to 80 Gy). In the second experiment, higher numbers of larvae were held in a manner resembling mass-rearing conditions, and were then irradiated with X-rays ranging from 0 to 10,417 R (equivalent to 100 Gy). In both experiments, the only factor that significantly affected fly emergence was irradiation of larvae. Fly emergence decreased markedly as the irradiation dose increased, and complete suppression of fly emergence was achieved at 6250.2 R (equivalent to 60 Gy) when larvae were irradiated in small batches with or without rearing media. Irradiation also affected the fertility of those flies that did emerge following treatment. In the second experiment, we found the parasitoids reared from irradiated larvae produced a higher parasitism rate and a higher number of female offspring than did parasitoids reared from control (non-irradiated) larvae. Mean fecundity of F1 parasitoids reared from irradiated larvae were affected positively by irradiation only at the 8333.6 R (80 Gy) dose. Our results show that X-ray irradiation can be used to inhibit fruit fly adult emergence and that irradiated larvae are at least as good a rearing substrate as non-irradiated larvae. Future studies should focus on the adjustment of our findings to a mass-rearing scale.  相似文献   

18.
Experimentally transmitted Ascarophis sp. (Spirurida) developed to adult worms in the invertebrate host, Gammarus deubeni (Amphipoda), collected in the intertidal zone in Passamaquoddy Bay, New Brunswick, Canada. The morphological development and growth of larval stages is very similar to other cystidicolids, which are found as adults in fish. Unlike virtually all other Spirurida, which require a vertebrate definitive host, infective larvae of Ascarophis sp. migrate from the invertebrate host musculature into the hemocoel where they molt twice to become adults. Gravid females appear at 80 days and 69 days post-infection at 10-12 C and 18-20 C, respectively. While there is little evident host reaction to the parasite within the muscle tissue, within the hemocoel there is hemocytic reaction to shed nematode cuticles, released eggs, and sometimes the worm itself, including some melanization. The worms are morphologically similar to Ascarophis sp. from G. oceanicus in the Baltic and White seas and among Ascarophis species from fish is most similar to A. arctica. It is suggested that Ascarophis sp. no longer requires a vertebrate host and is transmitted between amphipods either through death and disintegration of infected amphipods and dispersal of the nematode eggs, or more likely through cannibalism or necrophagy.  相似文献   

19.
Biological and biochemical parameters of a flightless strain of Harmonia axyridis, fed on a pork liver-based artificial diet and on Ephestia kuehniella eggs as controls, were compared. The diet-grown larvae showed a significantly longer developmental time and a lower adult emergence rate compared to control larvae. The weights of the newly emerged adults were significantly higher for adults fed E. kuehniella eggs during their larval stages than fed the artificial diet. In contrast, larval food source had no effect on the duration of the pre-oviposition period or adult longevity. For adults fed on E. kuehniella eggs as larvae, a significantly longer pre-oviposition period, lower daily weight gain and fecundity were found for the diet-fed females compared to those fed on E. kuehniella eggs throughout the life span. The adult food source had no significant effect on longevity and fertility. Lower amino acid and fatty acid contents (in particular C16:1 and C18:3n-3) were found for the prepupae and newly emerged females obtained from diet-reared larvae compared to controls. Deficiencies in fatty acids C16:1 and C18:3n-3 were also observed in females obtained from E. kuehniella egg-reared larvae and fed on diet from adult emergence. The analyses of the foods showed deficiencies in artificial diet, especially for some amino and fatty acids. The results suggest a non-optimal composition of the artificial diet and some possibilities for its improvement. However, this polyphagous predator could be reared from first instar larvae to fully reproductive adults on a pork liver-based artificial diet.  相似文献   

20.
观察了捕虱管蓟马的多种行为,认为该虫的日常行为为取食、行走、搜索、休息、交配和产卵;对所试验的5种害虫的喜好程度依次为椭圆蚧卵,柑桔木虱卵、褐圆蚧卵、柑桔粉虱卵、桔全爪螨若虫,褐圆蚧若虫、桔全爪螨卵、椭圆蚧若虫、柑桔木虱一龄 若虫,除柑桔木虱一龄若虫外,取食差异不显;捕虱管蓟马取食卵的量比若虫多,经T-检验分析,两无明显差异;室内饲养蓟马和田间采获蓟马的行为,及各行行为间差异,通过二因素方差分析显示不显;不同虫态蓟马取食时间长短依次为雌成虫、雄成虫、若虫、在食物充足的情况下,不同虫态之间几乎没有竞争,偶有成虫捕食幼虫现象发生。对该虫的交配行为及产卵行为作了详细的观察,发现雌蓟马成虫和雄蓟马成虫都多次交配;雄虫之间的性竞争十分激烈,而雌虫之间几乎没有竞争。  相似文献   

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