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1

Elucidating the spread of the emerging canid nematode Angiostrongylus vasorum between Palaearctic and Nearctic ecozones.  

PubMed

Angiostrongylus vasorum is an emerging parasite that is currently distributed through Western Europe and parts of South America. An isolated population is also present in Newfoundland, Canada. This presents a risk of onward spread into North America, but its origin is unknown. To ascertain the phylogeographic relationships and genetic diversity of A. vasorum within the western Palaearctic and eastern Nearctic ecozones, a total of 143 adult and larval nematode specimens were collected from foxes (Vulpes vulpes) and dogs (Canis lupus familiaris) in Canada, Denmark, France, Germany, Ireland, the Netherlands, Portugal and the United Kingdom, and a coyote (Canis latrans) in Canada. DNA was extracted and the second internal transcribed spacer and two mitochondrial loci were amplified and sequenced. Multiple haplotypes (n=35) based on combined mitochondrial sequences (1078bp) of the partial cytochrome oxidase subunit I (COI), large subunit ribosomal RNA (rrnL) and the complete nicotinamide adenine dinucleotide dehydrogenase 3 (NADH3) sequences, were observed throughout the Palaearctic countries sampled; however, only a single haplotype was observed for the Canadian A. vasorum population. The likely origin of A. vasorum in Newfoundland is therefore inferred to be within the western Palaearctic. There was no evidence of genetic segregation of parasites in dogs, foxes and coyotes, supporting the hypothesis that transmission occurs between wild and domestic canids. The transmission dynamics and population structure of this nematode are further discussed. PMID:20139034

Jefferies, R; Shaw, S E; Willesen, J; Viney, M E; Morgan, E R

2010-05-01

2

Angiostrongylus vasorum and Eucoleus aerophilus in foxes ( Vulpes vulpes) in Great Britain  

Microsoft Academic Search

The nematode parasite Angiostrongylus vasorum is a source of increasing concern in several parts of the world, where it causes significant disease in dogs. Wild canids, especially foxes, are likely to have a role in the epidemiology of canine infection, and the parasite could also affect fox health and population dynamics. The heart and pulmonary vasculature of 546 foxes culled

E. R. Morgan; A. Tomlinson; S. Hunter; T. Nichols; E. Roberts; M. T. Fox; M. A. Taylor

2008-01-01

3

Angiostrongylus cantonensis (Nematode: Metastrongiloidea): In Vitro Cultivation of Infective Third-Stage Larvae to Fourth-Stage Larvae  

PubMed Central

The present study to attempt to cultivate Angiostrongylus cantonensis from third-stage larvae (AcL3) to fourth-stage larvae (AcL4) in vitro in defined complete culture medium that contained with Minimum Essential Medium Eagle (MEM), supplemented amino acid (AA), amine (AM), fatty acid (FA), carbohydrate (CA) and 20% fetal calf serum (FCS) was successful. When AcL3 were cultured in the defined complete culture medium at 37°C in a 5% CO2 atmosphere, the larvae began to develop to AcL4 after 30 days of cultivation, and were enclosed within the sheaths of the third molts of the life cycle. Under these conditions, the larvae developed uniformly and reached to the fourth-stage 36 days. The morphology of AcL3 develop to AcL4 were recording and analyzing. Then comparison of A. cantonensis larval morphology and development between in vitro cultivation in defined complete culture medium and in vivo cultivation in infective BALB/c mice. The larvae that had been cultivated in vitro were smaller than AcL4 of infective BALB/c mice. However the AcL3 that were cultured using defined incomplete culture medium (MEM plus 20% FCS with AA+AM, FA, CA, AA+AM+FA, FA+CA, CA+AA+AM or not) did not adequately survive and develop. Accordingly, the inference is made that only the defined complete medium enable AcL3 develop to AcL4 in vitro. Some nematodes have been successfully cultured into mature worms but only a few researches have been made to cultivate A. cantonensis in vitro. The present study is the first to have succeeded in developing AcL3 to AcL4 by in vitro cultivation. Finally, the results of in vitro cultivation studies herein contribute to improving media for the effective development and growth of A. cantonensis. The gap in the A. cantonensis life cycle when the larvae are cultivated in vitro from third-stage larvae to fourth-stage larvae can thus be solved. PMID:23977214

Chung, Li-Yu; Lee, June-Der; Wang, Jiun-Jye; Yen, Chuan-Min

2013-01-01

4

Parasitological and hematological aspects of co-infection with Angiostrongylus vasorum and Ancylostoma caninum in dogs.  

PubMed

Dogs are frequently infected by one or more species of endoparasites, which can lead to secondary infections that cause high morbidity and death. In this context, 2 nematode species are of veterinary importance: Angiostrongylus vasorum, which is a parasite of the pulmonary artery and right ventricle in domestic and wild canids, and Ancylostoma caninum, which is a parasite of the small intestine in felids and domestic and wild canids. We used 20 mongrel dogs that were divided into groups and infected as follows: Group A included 5 uninfected dogs, Group B included 5 dogs infected with A. vasorum, Group C included 5 dogs infected with A. caninum, and Group D included 5 dogs co-infected with A. vasorum and A. caninum. Parasitological and hematological monitoring were performed. The counts of larvae and eggs shed in the feces varied throughout the collection period. Moreover, negativation was not observed in any of the infected groups. The animals in Group C had macrocytic and hypochromic anemia, whereas the animals in Group D had macrocytic and normochromic anemia. Infected dogs also presented with eosinophilia and lymphocytosis. These data from coproparasitological techniques provide an improved assessment of disease severity and a more thorough understanding of parasitism in the host. PMID:24373514

Dracz, Ruth Massote; Mozzer, Lanuze Rose; Fujiwara, Ricardo Toshio; Lima, Walter dos Santos

2014-02-24

5

Eosinophilic meningitis beyond the Pacific Basin: The global dispersal of a peridomestic zoonosis caused by angiostrongylus cantonensis, the nematode lungworm of rats  

Microsoft Academic Search

The principal etiologic agent of human eosinophilic meningitis, Angiostrongylus cantonensis, was first detected in rats in Canton, China in 1933. The first human case was detected on Taiwan in 1944. Epidemic outbreaks were noted on Ponape (E. Caroline Is.) from 1944 to 1948. The disease may present as transient meningitis or a more severe disease involving the brain, spinal cord

Michael M. Kliks; Nicholas E. Palumbo

1992-01-01

6

Angiostrongylus species in wild carnivores in the Iberian Peninsula.  

PubMed

A survey of Angiostrongylus parasites was carried out between 2003 and 2006 in wild carnivore species in the Basque Country (Northern Spain). Parasitological examination consisted in the dissection of heart and lungs for the extraction of adult worms. Nematodes were identified using morphometrical features and also PCR amplification and sequencing analysis. The animal species included in this study were Eurasian badger (Meles meles), Weasel (Mustela nivalis), Beech marten (Martes foina), Pine marten (Martes martes), Polecat (Mustela putorius), American mink (Mustela vison), Red fox (Vulpes vulpes), Wolf (Canis lupus), Wild cat (Felis silvestris), and Small-spotted genet (Genetta genetta). Angiostrongylus parasites were only found in foxes and badgers at prevalences of 33.3% and 24%, respectively. Identification of the nematodes by morphometrical features revealed that foxes were infected with A. vasorum while badgers were infected by a different species of Angiostrongylus most likely A. daskalovi. Sequencing data of the second internal transcribed spacer region of ribosomal DNA (ITS2) of isolates from each species confirmed the species difference. The high prevalence of Angiostrongylus found in the present survey, indicates that the wild cycle of two different species of Angiostrongylus is present in the Basque Country. To our knowledge this is the first report of A. daskalovi in the Iberian Peninsula. PMID:20728995

Gerrikagoitia, X; Barral, M; Juste, R A

2010-11-24

7

Eosinophilic meningitis beyond the Pacific Basin: the global dispersal of a peridomestic zoonosis caused by Angiostrongylus cantonensis, the nematode lungworm of rats.  

PubMed

The principal etiologic agent of human eosinophilic meningitis, Angiostrongylus cantonensis, was first detected in rats in Canton, China in 1933. The first human case was detected on Taiwan in 1944. Epidemic outbreaks were noted on Ponape (E. Caroline Is.) from 1944 to 1948. The disease may present as transient meningitis or a more severe disease involving the brain, spinal cord and nerve roots, with a characteristic eosinophilia of the peripheral blood and CSF. Since 1961 it has been known that human infections are usually acquired by purposeful or accidental ingestion of infective larvae in terrestrial mollusks, planaria and fresh-water crustacea. There is no effective specific treatment. The African land snail, Achatina fulica played an important role in the panpacific dispersal of the organism: it will be important in Africa in the future as well. Rats were, and will continue to be the principal agents of expansion of the parasite beyond the Indopacific area. During and just after WWII the parasite was introduced, and/or spread passively from South and Southeast Asia into the Western Pacific islands and eastward and southward through Micronesia, Melanesia, Australia and into Polynesia, sequestered in shipments of war material and facilitated by post-war commerce. In the 1950s numerous cases were identified for the first time on Sumatra, the Philippines, Taiwan, Saipan, New Caledonia, and as far east as Rarotonga and Tahiti. Then cases were detected in Vietnam, Thailand, Cambodia, Java, Sarawak, the New Hebrides, Guam and Hawaii during the 1960s. Subsequently in the Pacific Basin the disease has appeared on Okinawa, other Ryukyu islands, Honshu, Kyushu, New Britain, American Samoa and Western Samoa, Australia, Hong Kong, Bombay, India, Fiji and most recently in mainland China. The parasite in rats now occurs throughout the Indopacific Basin and littoral. Beyond the Indopacific region, the worm has been found in rodents in Madagascar (ca 1963), Cuba (1973), Egypt (1977), Puerto Rico (1984), New Orleans, Louisiana (1985) and Port Harcourt, Nigeria (1989). Human infections have now been detected in Cuba (1973), Réunion Island (1974) and Côte d'Ivoire (1979) and should be anticipated wherever infected rats of mollusks have been introduced. Caged primates became infected in zoos in Hong Kong (1978) and New Orleans and Nassau, Bahamas (1987). The use of mollusks and crustacea as famine foods, favored delicacies and medicines has resulted in numerous outbreaks and isolated infections. Economic and political instability, illicit trade, unsanitary peridomestic conditions and lack of health education promote the local occurrence and insidious global expansion of parasitic eosinophilic meningitis.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:1738873

Kliks, M M; Palumbo, N E

1992-01-01

8

Angiostrongylus vasorum in wolves in Italy.  

PubMed

In the past decade, the parasitic nematode Angiostrongylus vasorum has attracted attention for its emergence in previously free areas and for the rise in clinical cases in domestic dogs. Italy is regarded as one of the countries where this potentially life-threatening parasite is spreading, especially due to bridging infections between wildlife and domestic dogs. The present article describes the presence of A. vasorum in wolves from Italy. Nematodes were observed in histological sections of three wolves found dead in Rome province, central Italy. Morphological and molecular identification of the nematodes, by polymerase chain reaction of rDNA ITS-2 and sequencing, confirmed the nematodes to be A. vasorum, with 99% genetic homology with A. vasorum from sympatric dogs. This is the second report of this species in wolves and the first in this host in Italy, and coincides with increasing records of A. vasorum in dogs and foxes in Italy. Implications for the epidemiology of this emerging parasite and for wildlife health are concisely discussed. PMID:24918072

Eleni, Claudia; De Liberato, Claudio; Azam, Dena; Morgan, Eric R; Traversa, Donato

2014-04-01

9

Angiostrongylus vasorum in wolves in Italy?  

PubMed Central

In the past decade, the parasitic nematode Angiostrongylus vasorum has attracted attention for its emergence in previously free areas and for the rise in clinical cases in domestic dogs. Italy is regarded as one of the countries where this potentially life-threatening parasite is spreading, especially due to bridging infections between wildlife and domestic dogs. The present article describes the presence of A. vasorum in wolves from Italy. Nematodes were observed in histological sections of three wolves found dead in Rome province, central Italy. Morphological and molecular identification of the nematodes, by polymerase chain reaction of rDNA ITS-2 and sequencing, confirmed the nematodes to be A. vasorum, with 99% genetic homology with A. vasorum from sympatric dogs. This is the second report of this species in wolves and the first in this host in Italy, and coincides with increasing records of A. vasorum in dogs and foxes in Italy. Implications for the epidemiology of this emerging parasite and for wildlife health are concisely discussed. PMID:24918072

Eleni, Claudia; De Liberato, Claudio; Azam, Dena; Morgan, Eric R.; Traversa, Donato

2013-01-01

10

Angiostrongylus cantonensis and rat lungworm disease in Brazil.  

PubMed

The metastrongyloid nematode genus Angiostrongylus includes 18 species, two of which are relevant from a medical standpoint, Angiostrongylus costaricensis and Angiostrongylus cantonensis. The first was described from Costa Rica in 1971 and causes abdominal angiostrongyliasis in the Americas, including in Brazil. Angiostrongylus cantonensis, first described in 1935 from Canton, China, is the causative agent of eosinophilic meningitis. The natural definitive hosts are rodents, and molluscs are the intermediate hosts. Paratenic or carrier hosts include crabs, freshwater shrimp, amphibians, flatworms, and fish. Humans become infected accidentally by ingestion of intermediate or paratenic hosts and the parasite does not complete the life cycle as it does in rats. Worms in the brain cause eosinophilic meningitis. This zoonosis, widespread in Southeast Asia and the Pacific islands, has now been reported from other regions. In the Americas there are records from the United States, Cuba, Jamaica, Brazil, Ecuador, and Haiti. In Brazil seven human cases have been reported since 2007 from the southeastern and northeastern regions. Epidemiological studies found infected specimens of Rattus norvegicus and Rattus rattus as well as many species of molluscs, including the giant African land snail, Achatina fulica, from various regions of Brazil. The spread of angiostrongyliasis is currently a matter of concern in Brazil. PMID:23901376

Thiengo, Silvana Carvalho; Simões, Raquel de Oliveira; Fernandez, Monica Ammon; Maldonado, Arnaldo

2013-06-01

11

The first report of Angiostrongylus vasorum (Nematoda; Metastrongyloidea) in Poland, in red foxes (Vulpes vulpes).  

PubMed

Angiostrongylus vasorum belongs to the superfamily of Metastrongyloidea. This nematode occurs in foxes, dogs and other predators. The Nematode A. vasorum place themselves in the pulmonary artery and its branches, and in the right ventricle and atrium of the heart. Numerous species of land snails are the intermediate hosts of the parasite. In 2013, lungs and hearts of 76 foxes shot in the Forest District G??boki Bród in Augustowska Primeval Forest were parasitologically necropsied. Four of the examined foxes were infected with the nematode A. vasorum, a prevalence of 5.2%. In one fox pericardium there were 6 male and 6 female nematodes. In the remaining three foxes nematodes were localized in the pulmonary artery. In two foxes 2 specimens of nematodes were detected (male and female, and two females) while 1 female was detected in the other fox. This is the first report of the presence of the nematode A. vasorum in fox in Poland. PMID:25236289

Demiaszkiewicz, Aleksander W; Pyziel, Anna M; Kuligowska, Izabela; Lachowicz, Jacek

2014-10-01

12

Extraintestinal nematode infections of red foxes ( Vulpes vulpes) in Hungary  

Microsoft Academic Search

A survey was carried out to investigate the prevalence and worm burden of extraintestinal nematodes in 100 red foxes (Vulpes vulpes) of Hungary. The overall prevalence of nematode infections of the respiratory tract was 76%. Eucoleus aerophilus (Capillaria aerophila) was the predominant species (66%), followed by Crenosoma vulpis (24%), Eucoleus (Capillaria) böhmi (8%) and Angiostrongylus vasorum (5%). Pearsonema (Capillaria) plica

T. Sréter; Z. Széll; G. Marucci; E. Pozio; I. Varga

2003-01-01

13

On the diversity of mollusc intermediate hosts of Angiostrongylus costaricensis Morera & Cespedes, 1971 in southern Brazil.  

PubMed

Veronicellid slugs are considered the most important intermediate hosts of Angiostrongylus costaricensis, an intra-arterial nematode of rodents. Studies undertaken in three localities in southern Brazil led to identification of molluscs other than veronicellid slugs as hosts of A. costaricensis: Limax maximus, Limax flavus and Bradybaena similaris. These data indicate a low host specificity of larval stages of A. costaricensis, as it has been reported to other congeneric species. PMID:8107609

Teixeira, C G; Thiengo, S C; Thome, J W; Medeiros, A B; Camillo-Coura, L; Agostini, A A

1993-01-01

14

Gallus gallus domesticus: Paratenic host of Angiostrongylus vasorum.  

PubMed

Angiostrongylus vasorum, a parasite of the cardiorespiratory system in canids, has a heteroxenous biological cycle in which the intermediate hosts are terrestrial and aquatic mollusks. Generally, canids become infected by ingesting the intermediate host or paratenic hosts, such as amphibians, that contain infective larvae (L3). However, there are no reports of birds as paratenic hosts of A. vasorum. To evaluate the susceptibility and viability of Gallus gallus domesticus as a paratenic host of A. vasorum, 17 Cobb chickens were randomly divided into two groups. The animals in group A were inoculated with third stage larvae of A. vasorum, and those in group B ate snails inoculated with A. vasorum L3. At 30 days post-infection, the chickens were killed, and the muscles and organs were placed in a pepsin-HCl solution (1% HCl (37%), 1% pepsin) for 3h in an oven at 40°C to recover the L3. In group A, 1863 L3 were recovered per chicken. In group B, 2585 L3 were recovered. A dog that ingested organs and tissues from a chicken from group A released first-stage larvae of A. vasorum in its feces 51 days after infection; the dynamics of this process were monitored for 107 days, when treatment with 25mg fenbendazole/kg body weight was performed for 21 days. Chickens nourished with infected snails or with infective L3 may be a source of infection for dogs indicate that G. gallus is a potential paratenic host for this parasite. PMID:25468671

Mozzer, L R; Lima, W S

2014-11-15

15

Wild canids, domestic dogs and their pathogens in Southeast Brazil: disease threats for canid conservation  

Microsoft Academic Search

Wild canids are under many pressures, including habitat loss, fragmentation and disease. The current lack of information on\\u000a the status of wildlife health may hamper conservation efforts in Brazil. In this paper, we examined the prevalence of canine\\u000a pathogens in 21 free-ranging wild canids, comprising 12 Cerdocyon thous (crab-eating fox), 7 Chrysocyon brachyurus (maned wolf), 2 Lycalopex vetulus (hoary fox),

Nelson Henrique de Almeida Curi; Amanda Soriano Araújo; Fábia Souza Campos; Zélia Inês Portela Lobato; Solange Maria Gennari; Maria Fernanda Vianna Marvulo; Jean Carlos Ramos Silva; Sônia Aparecida Talamoni

2010-01-01

16

First report of Ancylostoma ceylanicum in wild canids.  

PubMed

The parasitic nematode Ancylostoma ceylanicum is common in dogs, cats and humans throughout Asia, inhabiting the small intestine and possibly leading to iron-deficient anaemia in those infected. It has previously been discovered in domestic dogs in Australia and this is the first report of A. ceylanicum in wild canids. Wild dogs (dingoes and dingo hybrids) killed in council control operations (n = 26) and wild dog scats (n = 89) were collected from the Wet Tropics region around Cairns, Far North Queensland. All of the carcasses (100%) were infected with Ancylostoma caninum and three (11.5%) had dual infections with A. ceylanicum. Scats, positively sequenced for hookworm, contained A. ceylanicum, A. caninum and Ancylostoma braziliense, with A. ceylanicum the dominant species in Mount Windsor National Park, with a prevalence of 100%, but decreasing to 68% and 30.8% in scats collected from northern and southern rural suburbs of Cairns, respectively. Due to the ability of A. ceylanicum to cause a patent infection in humans, the zoonotic risk arising from this wild dog reservoir to communities in the Wet Tropics should be determined. PMID:24533332

Smout, Felicity A; Thompson, R C Andrew; Skerratt, Lee F

2013-12-01

17

First report of Ancylostoma ceylanicum in wild canids?  

PubMed Central

The parasitic nematode Ancylostoma ceylanicum is common in dogs, cats and humans throughout Asia, inhabiting the small intestine and possibly leading to iron-deficient anaemia in those infected. It has previously been discovered in domestic dogs in Australia and this is the first report of A. ceylanicum in wild canids. Wild dogs (dingoes and dingo hybrids) killed in council control operations (n = 26) and wild dog scats (n = 89) were collected from the Wet Tropics region around Cairns, Far North Queensland. All of the carcasses (100%) were infected with Ancylostoma caninum and three (11.5%) had dual infections with A. ceylanicum. Scats, positively sequenced for hookworm, contained A. ceylanicum, A. caninum and Ancylostoma braziliense, with A. ceylanicum the dominant species in Mount Windsor National Park, with a prevalence of 100%, but decreasing to 68% and 30.8% in scats collected from northern and southern rural suburbs of Cairns, respectively. Due to the ability of A. ceylanicum to cause a patent infection in humans, the zoonotic risk arising from this wild dog reservoir to communities in the Wet Tropics should be determined. PMID:24533332

Smout, Felicity A.; Thompson, R.C. Andrew; Skerratt, Lee F.

2013-01-01

18

Biology, Systematics, Life Cycle, and Distribution of Angiostrongylus cantonensis, the Cause of Rat Lungworm Disease  

PubMed Central

Angiostrongylus cantonensis is a metastrongyloid nematode in the family Angiostrongylidae. It is the cause of angiostrongyliasis (rat lungworm disease), which manifests as eosinophilic meningitis. First described in 1935 from rats in China, A. cantonensis was placed in the genus Parastrongylus in 1986, but most workers have not adopted this treatment. The taxonomy of A. cantonensis and related worms is largely based on adult morphology, notably of the male bursa. However, identification of infective third stage larvae is more difficult. The natural life cycle involves rats as the definitive host and snails or slugs as the intermediate host. Human infection, as accidental hosts, results in worms maturing in the brain, but dying there instead of moving back into the bloodstream, as in rats, thereby leading to eosinophilic meningitis. The disease is an emerging infectious disease; Angiostrongylus cantonensis continues to be reported in new regions beyond its native range. PMID:23901372

2013-01-01

19

Environmental determinants of the spatial distribution of Angiostrongylus vasorum, Crenosoma vulpis and Eucoleus aerophilus in Hungary.  

PubMed

Angiostrongylus vasorum, Crenosoma vulpis and Eucoleus aerophilus (syn. Capillaria aerophila) are the most important lungworm species infecting wild and domesticated canids in Europe. To investigate the spatial distribution of these parasites and the factors influencing their circulation in the fox populations, 937 red foxes (Vulpes vulpes) were tested for lungworm infection in Hungary. The prevalence of A. vasorum, C. vulpis and E. aerophilus infection was high (17.9, 24.6 and 61.7%). The distribution pattern of infection in foxes and the relationship of this pattern with landscape and climate was analyzed by geographic information system. Based on the analysis, the annual precipitation was the major determinant of the spatial distribution of A. vasorum and C. vulpis and E. aerophilus. Nevertheless, the mean annual temperature also influenced the distribution of A. vasorum and E. aerophilus. The positive relationship with annual precipitation and the negative relationship with mean annual temperature can be attributed to the sensitivity of larvae, eggs and intermediate hosts (snails and slugs) of lungworms for desiccation. Based on the highly clumped distribution of A. vasorum and C. vulpis, the indirect life cycle (larvae, slugs and snails) of these parasites seems to be particularly sensitive for environmental effects. The distribution of E. aerophilus was considerably less clumped indicating a lower sensitivity of the direct life cycle (eggs) of this parasite for environmental factors. Based on these results, lungworm infections in canids including dogs can be expected mainly in relatively wet and cool areas. PMID:25547643

Tolnai, Z; Széll, Z; Sréter, T

2015-01-30

20

Angiostrongylus vasorum infection in a coyote (Canis latrans) from Newfoundland and Labrador, Canada.  

PubMed

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. PMID:16456176

Bourque, Andrea; Whitney, Hugh; Conboy, Gary

2005-10-01

21

5FOOD HABITS OF TWO SOUTH AMERICAN CANIDS Food habits of two syntopic canids, the maned wolf (Chrysocyon  

E-print Network

5FOOD HABITS OF TWO SOUTH AMERICAN CANIDS Food habits of two syntopic canids, the maned wolf Paulo, 05508-900, Brasil; e-mail: abueno@ib.usp.br ABSTRACT The maned wolf (Chrysocyon brachyurus ingested mainly animal food if biomass is considered. The maned wolf consumed more wolf's fruit (Solanum

Motta Junior, Jose Carlos

22

Human infections with Angiostrongylus cantonensis.  

PubMed

Angiostrongylus cantonensis is a parasite that causes eosinophilic meningitis and has been reported to be present on most Pacific islands. Rats are the principal host and several species of land snails the intermediate host. Important paratenic hosts are fresh water shrimp and fish. Modes of transmission include ingestion by man of raw fish, snails and fresh leafy vegetables contaminated by snail slime trails containing larvae. The parasitic worms are neurotropic in man, and the diagnosis should be considered in any adult or child, who presents, in endemic areas or areas with suitable intermediate hosts, with severe unrelenting headache, paresthesias, or a cranial nerve palsy. Eosinophils in the cerebral spinal fluid suggest the diagnosis. Simple analgesia is sufficient for mild cases. Treatment of those with severe symptoms remains controversial. Glucocorticoids, lumbar puncture to reduce intercranial pressure and antihelminthic agents have been used. PMID:12017820

Alto, W

2001-03-01

23

High throughput sequencing of the Angiostrongylus cantonensis genome: a parasite spreading worldwide.  

PubMed

Angiostrongylus cantonensis is a parasitic nematode of rodents and a leading aetiological agent of eosinophilic meningitis in humans. Definitive diagnosis is difficult, often relying on immunodiagnostic methods which utilize crude antigens. New immunodiagnostic methods based on recombinant proteins are being developed, and ideally these methods would be made available worldwide. Identification of diagnostic targets, as well as studies on the biology of the parasite, are limited by a lack of molecular information on Angiostrongylus spp. available in databases. In this study we present data collected from DNA random high-throughput sequencing together with proteomic analyses and a cDNA walking methodology to identify and obtain the nucleotide or amino acid sequences of unknown immunoreactive proteins. 28 080 putative ORFs were obtained, of which 3371 had homology to other deposited protein sequences. Using the A. cantonensis genomic sequences, 156 putative ORFs, matching peptide sequences obtained from previous proteomic studies, were considered novel, with no homology to existing sequences. Full-length coding sequences of eight antigenic target proteins were obtained. In this study we generated not only the complete nucleotide sequences of the antigenic protein targets but also a large amount of genomic data which may help facilitate future genomic, proteomic, transcriptomic or metabolomic studies on Angiostrongylus. PMID:23863082

Morassutti, Alessandra L; Perelygin, Andrey; DE Carvalho, Marcos O; Lemos, Leandro Nascimento; Pinto, Paulo Marcos; Frace, Mike; Wilkins, Patricia P; Graeff-Teixeira, Carlos; DA Silva, Alexandre J

2013-09-01

24

Neuroparasitic Infections: Nematodes  

PubMed Central

Globalization has produced an increase in the number of people at risk for contracting parasitic infection. Central nervous system infection by nematodal parasites can be devastating. Early recognition and treatment of infection can significantly decrease morbidity of the parasitic infection, as well as the risk of secondary superinfection. The clinical presentation, diagnosis, and treatment for five of the more common nematodal infections of the nervous system—Angiostrongylus spp., Baylisacaris procyonis, Gnathostoma spinigerum, Strongyloides stercoralis, and Toxocara spp.—is reviewed. Objectives On completion of this article, the reader should be able to summarize the clinical presentation, diagnosis, and treatment of the common nematodal infections of the nervous system. Accreditation The Indiana University School of Medicine is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. Credit The Indiana University School of Medicine designates this educational activity for a maximum of 1 Category 1 credit toward the AMA Physicians Recognition Award. Each physician should claim only those credits that he/she actually spent in the educational activity. Disclosure Statements of disclosure have been obtained regarding the authors’ relevant financial relationships. The authors have nothing to disclose. PMID:16170738

Walker, M.D.; Zunt, J.R.

2009-01-01

25

Filaroides osleri (Oslerus osleri): two case reports and a review of canid infections in North America.  

PubMed

Infections of domesticated dogs by a worldwide parasitic nematode Filaroides osleri (Oslerus osleri) lead to verminous tracheobronchitis that are often misdiagnosed clinically as kennel cough, due to infection with the bacterium Bordetella bronchiseptica. Diagnosis of two canine cases in Wyoming, USA prompted a search of the literature of canid infections in North America. Infections of domestic dogs are reported in nine US states and four Canadian provinces. Dogs of multiple breeds and both sexes were infected. Most were two years old or younger at diagnosis. Anthelmintic treatments were effective in relieving clinical symptoms, as well as causing resolution of tracheobronchial nodules. Other canid species, including coyotes (Canis latrans) and wolves (Canis lupus), have been infected across North America with a prevalence of 23% and 4%, respectively. Infection with F. osleri should be included in the differential diagnosis of infectious tracheobronchitis of dogs. It can be confirmed most readily by endoscopic detection of distinctive submucosal parasite-filled nodules, combined with histological examination of endoscopic biopsies. PMID:21411228

Yao, Chaoqun; O'Toole, Donal; Driscoll, Mike; McFarland, Warner; Fox, Jonathan; Cornish, Todd; Jolley, William

2011-06-30

26

Parasites of free-ranging small canids and felids in the Bolivian Chaco.  

PubMed

Parasite surveys of free-ranging wildlife provide important information for monitoring population health. Between March 2001 and March 2003, we sampled 10 ocelots (Leopardus pardalis), eight Geoffroy's cats (Oncifelis geoffroyi), a jaguarundi (Herpailurus yaguarondi), five pampas foxes (Pseudalopex gymnocercus), and three crab-eating foxes (Cerdocyon thous) at three sites in the Bolivian Chaco. The objective of the study was to survey the parasite fauna of these carnivores and compare prevalence of parasites among the sites. The parasite community of these carnivores was diverse, with representatives from eight genera of nematodes, two families of cestodes, two protozoan species, and six arthropod species. Fecal parasites identified from 12 of the 13 felids and five of the six canids examined included Aelurostrongylus abstrusus, Ancylostoma tubaeforme, Uncinaria sp., Crenosoma sp., Toxocara cati, Spirurida, Capillaria aerophila, Spirometra sp., Taeniidae, and Cystoisospora sp. Four tick species, Amblyomma parvum, A. tigrinum, A. ovale, and A. cajennense, and two flea species, Pulex irritans and Delostichus phyllotis, were identified. Two crab-eating foxes had serologic evidence of heartworm disease (HWD). Antibodies against Toxoplasma gondii were found in 15 of 26 animals. Although HWD was found only in canids inside the national park, parasite prevalence did not appear to differ among sites, and no evidence was found of parasite spillover from domestic to wild carnivores. PMID:17312790

Fiorello, Christine V; Robbins, Richard G; Maffei, Leonardo; Wade, Susan E

2006-06-01

27

Toxocara canis: genes expressed by the arrested infective larval stage of a parasitic nematode  

Microsoft Academic Search

Toxocara canis is a widely distributed nematode parasite which reaches maturity in dogs. However, eggs voided by canid animals are infective to a very wide range of paratenic hosts including humans. In noncanid hosts, infective larvae emerge from the eggs and invade the soft tissues, often entering the brain and musculature. Such larvae may remain for many months or years

Rick M. Maizels; Kevin K. A. Tetteh; Alex Loukas

2000-01-01

28

An analysis of prehistoric canid remains from Thailand  

Microsoft Academic Search

The prehistoric settlement site of Ban Chiang has yielded the remains of canid bones covering the period from c. 3500 BC to the present. These, and bones from related sites in northeast Thailand, were compared by multivariate means, with modern comparative samples of the wolf, dingo, cuon and jackal. Both in terms of size and shape, the prehistoric dog, though

C. F. W. Higham; A KIJNGAM; B MANLY

1980-01-01

29

Visceral leishmaniasis in captive wild canids in Brazil  

Microsoft Academic Search

Visceral leishmaniasis (VL) is endemic in Belo Horizonte (State of Minas Gerais, Brazil). Leishmania sp. can naturally infect several species of mammals, and the domestic dog is the most important reservoir of the disease in South America. This report describes five cases of visceral leishmaniasis in Brazilian canids. Among 15 animals kept in captivity in a zoo in Belo Horizonte

Marcela M. Luppi; Marcelo C. C. Malta; Teane M. A. Silva; Fabiana L. Silva; Rafael O. C. Motta; Ildikó Miranda; Roselene Ecco; Renato L. Santos

2008-01-01

30

Quantitative PCR estimates Angiostrongylus cantonensis (rat lungworm) infection levels in semi-slugs (Parmarion martensi)  

PubMed Central

The life cycle of the nematode Angiostrongylus cantonensis involves rats as the definitive host and slugs and snails as intermediate hosts. Humans can become infected upon ingestion of intermediate or paratenic (passive carrier) hosts containing stage L3 A. cantonensis larvae. Here, we report a quantitative PCR (qPCR) assay that provides a reliable, relative measure of parasite load in intermediate hosts. Quantification of the levels of infection of intermediate hosts is critical for determining A. cantonensis intensity on the Island of Hawaii. The identification of high intensity infection ‘hotspots’ will allow for more effective targeted rat and slug control measures. qPCR appears more efficient and sensitive than microscopy and provides a new tool for quantification of larvae from intermediate hosts, and potentially from other sources as well. PMID:22902292

Jarvi, Susan I.; Farias, Margaret E.M.; Howe, Kay; Jacquier, Steven; Hollingsworth, Robert; Pitt, William

2013-01-01

31

Nematode sperm  

Microsoft Academic Search

Parasitic nematode infections remain a major public health problem in many parts of the world. Because most of the current strategies aimed at controlling parasitic nematode infections have met with only limited success, it may be time to consider alternative approaches. An aspect of nematode biology that has drawn little attention as a target for control is the reproductive process.

A. L. Scott

1996-01-01

32

Visceral leishmaniasis in captive wild canids in Brazil.  

PubMed

Visceral leishmaniasis (VL) is endemic in Belo Horizonte (State of Minas Gerais, Brazil). Leishmania sp. can naturally infect several species of mammals, and the domestic dog is the most important reservoir of the disease in South America. This report describes five cases of visceral leishmaniasis in Brazilian canids. Among 15 animals kept in captivity in a zoo in Belo Horizonte (State of Minas Gerais, Brazil), two animals, a bush dog (Spheotos venaticos) and a hoary zorro (Lycalopex vetulus) were serologically positive and developed clinical signs of VL, whereas three other canids, including a crab-eating fox (Cerdocyon thous), a maned wolf (Chrysocyon brachyurus), and a hoary zorro (Lycalopex vetulus) had positive serological results without clinical signs. PMID:18556130

Luppi, Marcela M; Malta, Marcelo C C; Silva, Teane M A; Silva, Fabiana L; Motta, Rafael O C; Miranda, Ildikó; Ecco, Roselene; Santos, Renato L

2008-08-01

33

Abolition of Peroxiredoxin-5 Mitochondrial Targeting during Canid Evolution  

PubMed Central

In human, the subcellular targeting of peroxiredoxin-5 (PRDX5), a thioredoxin peroxidase, is dependent on the use of multiple alternative transcription start sites and two alternative in-frame translation initiation sites, which determine whether or not the region encoding a mitochondrial targeting sequence (MTS) is translated. In the present study, the abolition of PRDX5 mitochondrial targeting in dog is highlighted and the molecular mechanism underlying the loss of mitochondrial PRDX5 during evolution is examined. Here, we show that the absence of mitochondrial PRDX5 is generalized among the extant canids and that the first events leading to PRDX5 MTS abolition in canids involve a mutation in the more 5? translation initiation codon as well as the appearance of a STOP codon. Furthermore, we found that PRDX5 MTS functionality is maintained in giant panda and northern elephant seal, which are phylogenetically closely related to canids. Also, the functional consequences of the restoration of mitochondrial PRDX5 in dog Madin-Darby canine kidney (MDCK) cells were investigated. The restoration of PRDX5 mitochondrial targeting in MDCK cells, instead of protecting, provokes deleterious effects following peroxide exposure independently of its peroxidase activity, indicating that mitochondrial PRDX5 gains cytotoxic properties under acute oxidative stress in MDCK cells. Altogether our results show that, although mitochondrial PRDX5 cytoprotective function against oxidative stress has been clearly demonstrated in human and rodents, PRDX5 targeting to mitochondria has been evolutionary lost in canids. Moreover, restoration of mitochondrial PRDX5 in dog MDCK cells, instead of conferring protection against peroxide exposure, makes them more vulnerable. PMID:24023783

Van der Eecken, Valérie; Clippe, André; Dekoninck, Sophie; Goemaere, Julie; Walbrecq, Geoffroy; Van Veldhoven, Paul P.; Knoops, Bernard

2013-01-01

34

Nematode Songs  

NSDL National Science Digital Library

Nematode Songs is a wonderful, straightforward resource maintained by Nematologist Kathy Merrifield of Oregon State University, who makes light of these microscopic worms and parasites. A collection of 15 titles, including such notables as "Good King Nematode," "The Golden Sun" and "The Parasitic Nematode Rag," offer clever (and nematode-ish) lyrics to familiar songs. An option to sing along is included (requires MIDI sound), and each feature includes sheet music as well as complete lyrics. For the more serious, links to scientific nematode resources are provided at the bottom of the page.

Merrifield, Kathy.

35

Kin encounter rate and inbreeding avoidance in canids  

USGS Publications Warehouse

Mating with close kin can lead to inbreeding depression through the expression of recessive deleterious alleles and loss of heterozygosity. Mate selection may be affected by kin encounter rate, and inbreeding avoidance may not be uniform but associated with age and social system. Specifically, selection for kin recognition and inbreeding avoidance may be more developed in species that live in family groups or breed cooperatively. To test this hypothesis, we compared kin encounter rate and the proportion of related breeding pairs in noninbred and highly inbred canid populations. The chance of randomly encountering a full sib ranged between 1–8% and 20–22% in noninbred and inbred canid populations, respectively. We show that regardless of encounter rate, outside natal groups mates were selected independent of relatedness. Within natal groups, there was a significant avoidance of mating with a relative. Lack of discrimination against mating with close relatives outside packs suggests that the rate of inbreeding in canids is related to the proximity of close relatives, which could explain the high degree of inbreeding depression observed in some populations. The idea that kin encounter rate and social organization can explain the lack of inbreeding avoidance in some species is intriguing and may have implications for the management of populations at risk.

Geffen, Eli; Kam, Michael; Hefner, Reuven; Hersteinsson, Pall; Angerbjorn, Anders; Dalen, Love; Fuglei, Eva; Noren, Karin; Adams, Jennifer R.; Vicetich, John; Meier, Thomas J.; Mech, L.D.; VonHoldt, Bridgett M.; Stahler, Daniel R.; Wayne, Robert K.

2011-01-01

36

Kin encounter rate and inbreeding avoidance in canids  

USGS Publications Warehouse

Mating with close kin can lead to inbreeding depression through the expression of recessive deleterious alleles and loss of heterozygosity. Mate selection may be affected by kin encounter rate, and inbreeding avoidance may not be uniform but associated with age and social system. Specifically, selection for kin recognition and inbreeding avoidance may be more developed in species that live in family groups or breed cooperatively. To test this hypothesis, we compared kin encounter rate and the proportion of related breeding pairs in noninbred and highly inbred canid populations. The chance of randomly encountering a full sib ranged between 1-8% and 20-22% in noninbred and inbred canid populations, respectively. We show that regardless of encounter rate, outside natal groups mates were selected independent of relatedness. Within natal groups, there was a significant avoidance of mating with a relative. Lack of discrimination against mating with close relatives outside packs suggests that the rate of inbreeding in canids is related to the proximity of close relatives, which could explain the high degree of inbreeding depression observed in some populations. The idea that kin encounter rate and social organization can explain the lack of inbreeding avoidance in some species is intriguing and may have implications for the management of populations at risk. ?? 2011 Blackwell Publishing Ltd.

Geffen, E.; Kam, M.; Hefner, R.; Hersteinsson, P.; Angerbjorn, A.; Dalen, L.; Fuglei, E.; Noren, K.; Adams, J.R.; Vucetich, J.; Meier, T.J.; Mech, L.D.; Vonholdt, B.M.; Stahler, D.R.; Wayne, R.K.

2011-01-01

37

Hemoplasmas in wild canids and felids in Brazil.  

PubMed

Hemotropic mycoplasmas, epicellular erythrocytic bacterial parasites lacking a cell wall, are the causative agents of infectious anemia in numerous mammalian species. The presence of hemotropic mycoplasmas in blood samples of neotropical and exotic wild canids and felids from Brazilian zoos were recorded using molecular techniques. Blood samples were collected from 146 Brazilian wild felids, 19 exotic felids, 3 European wolves (Canis lupus), and from 97 Brazilian wild canids from zoos in the Brazilian states of São Paulo and Mato Grosso and the Federal District. Using conventional polymerase chain reaction (PCR), this work found 22 (13%) wild felids positive to Candidatus Mycoplasma haemominutum [4 jaguars (Panthera onca); 3 pumas (Puma concolor); 10 ocelots (Leopardus pardalis); 2 jaguarondis (Puma yagouaroundi); and 3 little spotted cats (Leopardus tigrinus)]. Only one little spotted cat (Leopardus tigrinus) was positive to Mycoplasma haemofelis, and none was positive to Candidatus Mycoplasma turicensis. Two bush dogs (Speothos venaticus) were positive for a Mycoplasma sp. closely related to Candidatus Mycoplasma haematoparvum, and two European wolves were positive for a Mycoplasma sp. closely related to Candidatus Mycoplasma haemominutum. This is the first study regarding the molecular detection of hemotropic mycoplasmas in wild canids. PMID:22946419

André, Marcos Rogerio; Adania, Cristina Harumi; Allegretti, Silmara Marques; Machado, Rosangela Zacarias

2011-06-01

38

Nematode sperm.  

PubMed

Parasitic nematode infections remain a major public health problem in many parts of the world. Because most of the current strategies aimed at controlling parasitic nematode infections have met with only limited success, it may be time to consider alternative approaches. An aspect of nematode biology that has drawn little attention as a target for control is the reproductive process. Although there are numerous facets of the overall reproductive biology of nematodes that hold potential as targets for intervention, Alan Scott here focuses on the male reproductive system, and outlines some of the known unique processes and characteristics of sperm formation and sperm function that could be exploited to block fertilization. PMID:15275275

Scott, A L

1996-11-01

39

The interrelationships of chromosome banding patterns in canids, mustelids, hyena, and felids  

Microsoft Academic Search

The G-banding patterns of six canids, four mustelids, one hyena, and 12 felids have been studied, and data from the study of 30 felids are summarized. The canids are karyotypically very similar to one another, but minor differences have tentatively been identified. The mustelids show the greatest karyotypic diversity of all the carnivore families so far studied. They do display,

D. H. Wurster-Hill; W. R. Centerwall

1982-01-01

40

Polygynandry in a red fox population: implications for the evolution of group living in canids?  

Microsoft Academic Search

Canid social groups are typically thought to consist of extended families, that is, a dominant breeding pair and related nonbreeding subordinates, that principally obtain indirect fitness benefits from helping to raise the offspring of the dominant pair. Consequently, the monogamous pair has been viewed as the basic fundamental unit of canid social organization. However, there have been few genetic studies

Philip J. Baker; Stephan M. Funk; Michael W. Bruford; Stephen Harrisa

2004-01-01

41

Respiratory and olfactory turbinal size in canid and arctoid carnivorans.  

PubMed

Within the nasal cavity of mammals is a complex scaffold of paper-thin bones that function in respiration and olfaction. Known as turbinals, the bones greatly enlarge the surface area available for conditioning inspired air, reducing water loss, and improving olfaction. Given their functional significance, the relative development of turbinal bones might be expected to differ among species with distinct olfactory, thermoregulatory and/or water conservation requirements. Here we explore the surface area of olfactory and respiratory turbinals relative to latitude and diet in terrestrial Caniformia, a group that includes the canid and arctoid carnivorans (mustelids, ursids, procyonids, mephitids, ailurids). Using high-resolution computed tomography x-ray scans, we estimated respiratory and olfactory turbinal surface area and nasal chamber volume from three-dimensional virtual models of skulls. Across the Caniformia, respiratory surface area scaled isometrically with estimates of body size and there was no significant association with climate, as estimated by latitude. Nevertheless, one-on-one comparisons of sister taxa suggest that arctic species may have expanded respiratory turbinals. Olfactory surface area scaled isometrically among arctoids, but showed positive allometry in canids, reflecting the fact that larger canids, all of which are carnivorous, had relatively greater olfactory surface areas. In addition, among the arctoids, large carnivorous species such as the polar bear (Ursus maritimus) and wolverine (Gulo gulo) also displayed enlarged olfactory turbinals. More omnivorous caniform species that feed on substantial quantities of non-vertebrate foods had less expansive olfactory turbinals. Because large carnivorous species hunt widely dispersed prey, an expanded olfactory turbinal surface area may improve a carnivore's ability to detect prey over great distances using olfactory cues. PMID:23035637

Green, Patrick A; Van Valkenburgh, Blaire; Pang, Benison; Bird, Deborah; Rowe, Timothy; Curtis, Abigail

2012-12-01

42

Bartonella clarridgeiae and Bartonella vinsonii subsp. berkhoffii exposure in captive wild canids in Brazil.  

PubMed

SUMMARY Wild canids are potential hosts for numerous species of Bartonella, yet little research has been done to quantify their infection rates in South America. We sought to investigate Bartonella seroprevalence in captive wild canids from 19 zoos in São Paulo and Mato Grosso states, Brazil. Blood samples were collected from 97 wild canids belonging to four different native species and three European wolves (Canis lupus). Indirect immunofluorescent antibody testing was performed to detect the presence of B. henselae, B. vinsonii subsp. berkhoffii, B. clarridgeiae, and B. rochalimae. Overall, Bartonella antibodies were detected in 11 of the canids, including five (12·8%) of 39 crab-eating foxes (Cerdocyon thous), three (11·1%) of 27 bush dogs (Speothos venaticus), two (8·7%) of 23 maned wolves (Chrysocyon brachyurus) and one (12·5%) of eight hoary foxes (Lycalopex vetulus), with titres ranging from 1:64 to 1:512. Knowing that many species of canids make excellent reservoir hosts for Bartonella, and that there is zoonotic potential for all Bartonella spp. tested for, it will be important to conduct further research in non-captive wild canids to gain an accurate understanding of Bartonella infection in free-ranging wild canids in South America. PMID:24892580

Fleischman, D A; Chomel, B B; Kasten, R W; André, M R; Gonçalves, L R; Machado, R Z

2015-02-01

43

A shared system of representation governing quantity discrimination in canids.  

PubMed

One way to investigate the evolution of cognition is to compare the abilities of phylogenetically related species. The domestic dog (Canis lupus familiaris), for example, still shares cognitive abilities with the coyote (Canis latrans). Both of these canids possess the ability to make psychophysical "less/more" discriminations of food based on quantity. Like many other species including humans, this ability is mediated by Weber's Law: discrimination of continuous quantities is dependent on the ratio between the two quantities. As two simultaneously presented quantities of food become more similar, choice of the large or small option becomes random in both dogs and coyotes. It remains unknown, however, whether these closely related species within the same family - one domesticated, and one wild - make such quantitative comparisons with comparable accuracy. Has domestication honed or diminished this quantitative ability? Might different selective and ecological pressures facing coyotes drive them to be more or less able to accurately represent and discriminate food quantity than domesticated dogs? This study is an effort to elucidate this question concerning the evolution of non-verbal quantitative cognition. Here, we tested the quantitative discrimination ability of 16 domesticated dogs. Each animal was given nine trials in which two different quantities of food were simultaneously displayed to them. The domesticated dogs' performance on this task was then compared directly to the data from 16 coyotes' performance on this same task reported by Baker et al. (2011). The quantitative discrimination abilities between the two species were strikingly similar. Domesticated dogs demonstrated similar quantitative sensitivity as coyotes, suggesting that domestication may not have significantly altered the psychophysical discrimination abilities of canids. Instead, this study provides further evidence for similar non-verbal quantitative abilities across multiple species. PMID:23060847

Baker, Joseph M; Morath, Justice; Rodzon, Katrina S; Jordan, Kerry E

2012-01-01

44

Angiostrongylus costaricensis (Nematoda: Protostrongylidae): migration route in experimental infection of Omalonyx sp. (Gastropoda: Succineidae).  

PubMed

Angiostrongylus costaricensis can infect several mollusks, and its migration route in intermediate hosts has been studied only in Sarasinula marginata. To verify the susceptibility of Omalonyx sp. as an intermediate host of A. costaricensis and to analyze the nematode migration route, individuals were infected with stage 1 larvae. Obtained stage 3 larvae were orally inoculated in mice, and after 30 days, adult worms and stage 1 larvae were recovered, demonstrating Omalonyx susceptibility and suitability to infection. To define the parasite migration routes, specimens of Omalonyx with 30 min, 1 h, 2 h, 4 h, 6 h, 8 h, 2 days, 5 days, 10 days, 12 days, 15 days, 20 days, 21 days, 25 days, 28 days, and 30 days of infection were fixed and serially sectioned. Histological sections were stained with hematoxylin-eosin. The results were compared to those described in S. marginata. Oral and cutaneous infections were noted. After the penetration, larvae were retained, mainly in the fibromuscular tissue, by hemocytes, or they spread to the whole organism through the circulation, following the anatomical structure of the vasculature. The perilarval hemocyte reaction in Omalonyx was more intense until stage 2 larva instar, decreasing in the presence of stage 3 larvae. Differences in some aspects of hemocyte reaction between S. marginata and Omalonyx exemplify interspecific peculiarities in snail response to the same parasite. PMID:18712530

Montresor, Lângia C; Vidigal, Teofânia H D A; Mendonça, Cristiane L G F; Fernandes, André A; de Souza, Karyne N; Carvalho, Omar S; Caputo, Luzia F G; Mota, Ester M; Lenzi, Henrique L

2008-11-01

45

Infectious diseases in Yellowstone’s canid community  

USGS Publications Warehouse

Each summer Yellowstone Wolf Project staff visit den sites to monitor the success of wolf reproduction and pup rearing behavior. For the purposes of wolf monitoring, Yellowstone National Park (YNP) is divided into two study areas, the northern range and the interior, each distinguished by their ecological and physiographical differences. The 1,000 square kilometer northern range, characterized by lower elevations (1,500–2,200 m), serves as prime winter habitat for ungulates and supports a higher density of wolves than the interior (20–99 wolves/1,000 km2 versus 2–11 wolves/1,000 km2). The interior of the park encompasses 7,991 square kilometers, is higher in elevation, receives higher annual snowfall, and generally supports lower densities of wolves and ungulates. During the Yellowstone Wolf Project’s 2005 observations on the northern range, researchers noticed that some wolf pups were disappearing and those that remained were unusually listless. The Slough Creek pups, at first numbering 18, dwindled to three survivors. Similar findings were mirrored at other den sites across the northern range. When annual den surveys were conducted in late July, all that remained were scattered piles of bones and fur. Coyotes suffered similar setbacks in 2005, with many of the survivors exhibiting neurological shakes and tremors. The park’s canids had been affected by something, but what? Prompted by what seemed to be a disease outbreak, the Yellowstone Wolf Project, the Yellowstone Ecological Research Center (YERC), and the University of Minnesota decided to take several collaborative approaches toward improving our understanding of the presence and role of infectious disease in Yellowstone’s canid community. Several serological studies have been conducted in the past among the park’s coyotes (Gese et al. 1997) and cougars (Biek 2006), providing a helpful foundation on which to build and compare. A serological survey was conducted, using serum samples collected during routine wolf and coyote captures over a period of 18 years (Almberg et al. 2009). Simulation models were used to explore the dynamics of canine distemper virus (Almberg et al. 2010)—one of the more prominent pathogens in terms of its effects on its hosts—and several long-term pathogen surveillance projects were initiated which are intended to someday provide a foundation for more advanced genetic-based analyses of pathogen dynamics. Since these initial efforts, the group has also expanded the research to include a study of sarcoptic mange, which began affecting wolves and coyotes in YNP in 2006 and 2007.

Almberg, Emily S.; Cross, Paul C.; Mech, L. David; Smith, Doug W.; Sheldon, Jennifer W.; Crabtree, Robert L.

2011-01-01

46

Complete mitochondrial genomes of ancient canids suggest a European origin of domestic dogs.  

PubMed

The geographic and temporal origins of the domestic dog remain controversial, as genetic data suggest a domestication process in East Asia beginning 15,000 years ago, whereas the oldest doglike fossils are found in Europe and Siberia and date to >30,000 years ago. We analyzed the mitochondrial genomes of 18 prehistoric canids from Eurasia and the New World, along with a comprehensive panel of modern dogs and wolves. The mitochondrial genomes of all modern dogs are phylogenetically most closely related to either ancient or modern canids of Europe. Molecular dating suggests an onset of domestication there 18,800 to 32,100 years ago. These findings imply that domestic dogs are the culmination of a process that initiated with European hunter-gatherers and the canids with whom they interacted. PMID:24233726

Thalmann, O; Shapiro, B; Cui, P; Schuenemann, V J; Sawyer, S K; Greenfield, D L; Germonpré, M B; Sablin, M V; López-Giráldez, F; Domingo-Roura, X; Napierala, H; Uerpmann, H-P; Loponte, D M; Acosta, A A; Giemsch, L; Schmitz, R W; Worthington, B; Buikstra, J E; Druzhkova, A; Graphodatsky, A S; Ovodov, N D; Wahlberg, N; Freedman, A H; Schweizer, R M; Koepfli, K-P; Leonard, J A; Meyer, M; Krause, J; Pääbo, S; Green, R E; Wayne, R K

2013-11-15

47

Prevalence of antibodies to Leishmania infantum and Trypanosoma cruzi in wild canids from South Carolina.  

PubMed

Wild canids are reservoir hosts for Leishmania infantum and Trypanosoma cruzi. The present study examined the prevalence of antibodies to these zoonotic parasites in a population of wild canids from a nonagricultural setting in South Carolina. Sera from 26 gray foxes (Urocyon cinereoargenteus) and 2 coyotes (Canis latrans) were examined for antibodies to L. infantum and T. cruzi using the indirect immunofluorescent antibody test and commercially available parasite-specific immunochromatigraphic strip assays. Antibodies to L. infantum were not detected by either assay in gray foxes or coyotes. Two (8%) of 26 gray foxes were positive in both the T. cruzi immunofluorescent antibody and strip assays. Antibodies to T. cruzi were not detected in coyotes. Results from this study indicate that wild canids are exposed to T. cruzi, but not L. infantum. in this geographic region. PMID:17918387

Rosypal, Alexa C; Tidwell, Richard R; Lindsay, David S

2007-08-01

48

Artificial insemination in canids: A useful tool in breeding and conservation  

Microsoft Academic Search

Artificial insemination (AI) and semen freezing have become services available to dog owners worldwide, and the demand for services to freeze semen is increasing. In other canids such as the fox, the fur industry utilizes fresh or frozen semen to artificially inseminate vixens to produce pelts. Clearly, AI facilitates the use of a male to sire several females by diluting

R. Thomassen; W. Farstad

2009-01-01

49

Major histocompatibility complex (MHC) variation in the endangered Mexican wolf and related canids1  

Microsoft Academic Search

We have examined in Mexican wolves and related canids the amount of genetic variation for a class II gene in the major histocompatibility complex (MHC), thought to be part of the most important genetic basis for pathogen resistance in vertebrates. In Mexican wolves, descended from only seven founders over three lineages, there were five different alleles. These were in three

Philip W. Hedrick; Rhonda N. Lee; Karen M. Parker

2000-01-01

50

The role of eosinophils in Angiostrongylus cantonensis infection.  

PubMed

Angiostrongylus cantonensis is the causative agent of human eosinophilic meningoencephalitis in the Pacific Islands and Southeast Asia. Prominent eosinophilia in the cerebrospinal fluid (CSF) of the patients has been used as one of the diagnostic criteria for the disease but the role(s) of the CSF eosinophils has remained to be elucidated. In this article, Kentaro Yoshimura, Hiroko Sugaya and Kazuto Ishido discuss the involvement of CSF eosinophils in the killing of intracranial worms and the damage of the central nervous system of the hosts, and consider why eosinophils in A. cantonensis infection play a more important role in nonpermissive hosts (including humans) than in the permissive rat host. PMID:15275458

Yoshimura, K; Sugaya, H; Ishida, K

1994-06-01

51

Nematodes (Rhabditida: Steinernematidae and Heterorhabditidae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nematodes are roundworms in the phylum Nematoda. Although most are free-living, some nematodes are parasites of plants, humans, or livestock. Entomopathogenic nematodes in the families Steinernematidae & Heterorhabditidae only parasitize insects. These nematodes are used as environmentally friend...

52

Biochemical profile of Achatina fulica (Mollusca: Gastropoda) after infection by different parasitic loads of Angiostrongylus cantonensis (Nematoda, Metastrongylidae).  

PubMed

The effect of experimental infection by different parasitic loads of Angiostrongylus cantonensis (Nematode, Metastrongylidae) on the activities of the aminotransferases and concentration of total proteins, uric acid and urea in the hemolymph of Achatina fulica (Mollusca, Gastropoda) were investigated. There was a significant decrease in the concentration of total proteins in the exposed snails to 5000 or more larvae. This change was accompanied by an increase in the concentrations of urea and uric acid in the hemolymph, suggesting a higher rate of deamination of the amino acids. Besides this, variations in the activities of the aminotransferases were also observed, with the highest values recorded in the groups exposed to greater parasite load. These results suggest an increase in the use of total proteins, since there was increased formation of nitrogenous catabolites, in conformity with an increase in the aminotransferase activities. Infection was verified by the fact that L3 larvae recovered from the snails was proportion to the exposure dose of L1 larvae. Histopathological results also indicated presence of an inflammatory cell infiltrate, favoring an increase of both transaminases. PMID:25308279

Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Amaral, Ludimila Santos; Mota, Esther Maria; Júnior, Arnaldo Maldonado; Pinheiro, Jairo; Garcia, Juberlan

2015-01-01

53

Identification and characterisation of microRNAs in young adults of Angiostrongylus cantonensis via a deep-sequencing approach  

PubMed Central

Angiostrongylus cantonensis is an important causative agent of eosinophilic meningitis and eosinophilic meningoencephalitis in humans. MicroRNAs (miRNAs) are small non-coding RNAs that participate in a wide range of biological processes. This study employed a deep-sequencing approach to study miRNAs from young adults of A. cantonensis. Based on 16,880,456 high-quality reads, 252 conserved mature miRNAs including 10 antisense miRNAs that belonging to 90 families, together with 10 antisense miRNAs were identified and characterised. Among these sequences, 53 miRNAs from 25 families displayed 50 or more reads. The conserved miRNA families were divided into four groups according to their phylogenetic distribution and a total of nine families without any members showing homology to other nematodes or adult worms were identified. Stem-loop real-time polymerase chain reaction analysis of aca-miR-1-1 and aca-miR-71-1 demonstrated that their level of expression increased dramatically from infective larvae to young adults and then decreased in adult worms, with the male worms exhibiting significantly higher levels of expression than female worms. These findings provide information related to the regulation of gene expression during the growth, development and pathogenesis of young adults of A. cantonensis. PMID:24037191

Chang, Shih-Hsin; Tang, Petrus; Lai, Cheng-Hung; Kuo, Ming-Ling; Wang, Lian-Chen

2013-01-01

54

Effects of Washing Produce Contaminated with the Snail and Slug Hosts of Angiostrongylus cantonensis with Three Common Household Solutions  

PubMed Central

The emerging infectious disease angiostrongyliasis (rat lungworm disease) is caused by ingesting snails and slugs infected by the nematode Angiostrongylus cantonensis. The definitive hosts of A. cantonensis are rats and the obligatory intermediate hosts are slugs and snails. Many cases result from accidentally ingesting infected snails or slugs on produce (eg, lettuce). This study assessed three readily available household products as washing solutions for removing snails and slugs from produce (romaine lettuce) to lower the probability of accidentally ingesting them. The solutions were acetic acid (vinegar), sodium hypochlorite (bleach), and sodium chloride (domestic salt). Snail and slug species known to be intermediate hosts and that are common in the Hawaiian Islands were used in the experiments: the alien snail Succinea tenella, the alien semi-slug Parmarion martensi, and the alien slugs Veronicella cubensis and Deroceras laeve. None of the products was any more effective than washing and rinsing with tap water alone. Most snails and slugs were removed after treatment but some remained on the lettuce even after washing and rinsing the produce. Only washing, rinsing, and then rinsing each leaf individually resulted in complete removal of all snails and slugs. The study did not address removal of any remaining slime left by the snails and slugs, nor did it address killing of worms. PMID:23901391

Yeung, Norine W; Hayes, Kenneth A

2013-01-01

55

Diseases Caused by Nematodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nematodes are important yield limiting factors in soybean production world wide. This article is a short, general introduction of nematodes for non nematologists and is a section of a larger soybean disease compendium....

56

Control measures for slug and snail hosts of Angiostrongylus cantonensis, with special reference to the semi-slug Parmarion martensi.  

PubMed

Slugs and snails (class Gastropoda) are the obligate intermediate hosts of the rat lungworm, Angiostrongylus cantonensis. This nematode is the causative agent of human angiostrongyliasis and the most common cause of human eosinophilic meningoencephalitis. Humans can become infected by accidental consumption of slugs or snails and possibly flatworms (or a portion of one of these animals) in fresh produce, but the slime from these animals can contain nematodes and may also constitute a disease risk. Gastropod carriers in Hawa'i include, among other species, giant African snails, veronicellid slugs, and the semi-slug Parmarion martensi. This latter species was first discovered on the island of Hawa'i in 2004 and is now common in the area where the majority of the state's documented cases of human angiostrongyliasis occurred between 2005 and 2011. This species is considered a high risk carrier of A. cantonensis because of its climbing behavior, abundance around human dwellings, and high worm burdens. One individual collected from east Hawa'i Island contained >6,800 infective third stage A. cantonensis larvae. Common and efficient control methods for slugs and snails include sanitation (eg, removal of objects that serve as hiding places) and the use of poison food baits, such as those containing metaldehyde and iron. An iron-containing bait that is relatively safe to non-target organisms was effective in controlling semi-slugs in cage experiments, although it killed more slowly than a metaldehyde-containing bait and the majority of slugs affected did not die until 1-2 weeks following ingestion. PMID:23901389

Hollingsworth, Robert G; Howe, Kathleen; Jarvi, Susan I

2013-06-01

57

Control Measures for Slug and Snail Hosts of Angiostrongylus cantonensis, with Special Reference to the Semi-slug Parmarion martensi  

PubMed Central

Slugs and snails (class Gastropoda) are the obligate intermediate hosts of the rat lungworm, Angiostrongylus cantonensis. This nematode is the causative agent of human angiostrongyliasis and the most common cause of human eosinophilic meningoencephalitis. Humans can become infected by accidental consumption of slugs or snails and possibly flatworms (or a portion of one of these animals) in fresh produce, but the slime from these animals can contain nematodes and may also constitute a disease risk. Gastropod carriers in Hawa‘i include, among other species, giant African snails, veronicellid slugs, and the semi-slug Parmarion martensi. This latter species was first discovered on the island of Hawa‘i in 2004 and is now common in the area where the majority of the state's documented cases of human angiostrongyliasis occurred between 2005 and 2011. This species is considered a high risk carrier of A. cantonensis because of its climbing behavior, abundance around human dwellings, and high worm burdens. One individual collected from east Hawa‘i Island contained >6,800 infective third stage A. cantonensis larvae. Common and efficient control methods for slugs and snails include sanitation (eg, removal of objects that serve as hiding places) and the use of poison food baits, such as those containing metaldehyde and iron. An iron-containing bait that is relatively safe to non-target organisms was effective in controlling semi-slugs in cage experiments, although it killed more slowly than a metaldehyde-containing bait and the majority of slugs affected did not die until 1–2 weeks following ingestion. PMID:23901389

Howe, Kathleen; Jarvi, Susan I

2013-01-01

58

Transferability of short tandem repeat markers for two wild Canid species inhabiting the Brazilian Cerrado.  

PubMed

The maned wolf (Chrysocyon brachyurus) and the crab-eating fox (Cerdocyon thous) are two wild-canid species found in the Brazilian Cerrado. We tested cross-amplification and transferability of 29 short tandem repeat primers originally developed for cattle and domestic dogs and cats on 38 individuals of each of these two species, collected in the Emas National Park, which is the largest national park in the Cerrado region. Six of these primers were successfully transferred (CSSM-038, PEZ-05, PEZ-12, LOCO-13, LOCO-15, and PEZ-20); five of which were found to be polymorphic. Genetic parameter values (number of alleles per locus, observed and expected heterozygosities, and fixation indices) were within the expected range reported for canid populations worldwide. PMID:17183492

Rodrigues, F M; Telles, M P C; Resende, L V; Soares, T N; Diniz-Filho, J A F; Jácomo, A T A; Silveira, L

2006-01-01

59

Heavy metals in hair of wild canids from the Brazilian Cerrado.  

PubMed

In this study, we aimed to assess whether free-ranging wild canids are exposed to heavy metals in one of the most developed and populated regions of Brazil. Hair of 26 wild canids (maned wolves Chrysocyon brachyurus, crab-eating foxes Cerdocyon thous, and hoary foxes Lycalopex vetulus) from the Cerrado biome in Southeast Brazil were analyzed by spectrophotometry to detect cadmium, chromium, and lead, and also the essential copper, iron, manganese, and zinc traces. All samples showed traces of copper, iron, manganese, and zinc. Non-essential lead was detected in 57% (2.35 ± 0.99 mg/kg), and chromium in 88% (2.98 ± 1.56 mg/kg) of samples. Cadmium traces (detection limit 0.8 mg/kg) were not found. Crab-eating foxes had more copper, iron, and manganese in hair than maned wolves. Correlations among element levels differed between maned wolves and crab-eating foxes. Concentrations of chromium and lead were outstandingly higher than in wild canids from other areas. Addressing the causes of such levels and the impacts of the heavy metal pollution in Neotropical ecosystems is urgent for animal health and conservation purposes. We argue that heavy metal pollution should be considered as dangerous threats to wildlife health in Brazil and recommend hair sampling as a biomonitoring tool for heavy metals in Neotropical terrestrial mammals. PMID:22201044

Curi, Nelson Henrique de Almeida; Brait, Carlos Henrique Hoff; Antoniosi Filho, Nelson Roberto; Talamoni, Sônia Aparecida

2012-06-01

60

Naturally occurring and melengestrol acetate-associated reproductive tract lesions in zoo canids.  

PubMed

As husbandry practices have improved, safe and effective contraception for captive wildlife management has become a necessity. Melengestrol acetate (MGA), a synthetic progestin, is highly effective and has been used in many zoo species. Long-term use of MGA has been associated with uterine lesions in zoo felids, but effects in zoo canids have not been evaluated. This retrospective study documented spontaneously occurring lesions and investigated the impact of MGA on the reproductive health of zoo canids. Reproductive tracts from adult females were submitted by US zoos to the Association of Zoos & Aquariums' Wildlife Contraception Center Health Surveillance Program. Reproductive tracts were sampled and processed for histopathologic examination following standard protocols. Microscopic evaluations were performed without prior knowledge of MGA treatment status. Prevalence of uterine lesions was evaluated and compared between MGA-treated animals (n = 20) and control (untreated) animals (n = 61). Common lesions within the study population as a whole included endometrial hyperplasia (predominantly cystic) (53%), hydrometra (33%), and adenomyosis (25%). Treatment with MGA was a risk factor for endometrial hyperplasia, hydrometra, fibrosis, and adenomyosis. Uterine mineralization occurred exclusively in MGA-treated animals. Results indicate that MGA contraception can lead to lesions that may permanently impair the fertility of females. Therefore, if long-term contraception of zoo canids is necessary, the use of alternate methods of reproductive control such as gonadotropin-releasing hormone (GnRH) analogs or GnRH vaccines that reduce gonadal hormone exposure should be pursued. PMID:19605907

Moresco, A; Munson, L; Gardner, I A

2009-11-01

61

[Seroprevalence of antibodies anti-Neospora caninum and anti-Toxoplasma gondii in captive wild canids].  

PubMed

Neosporosis is considered one of the main cause of abortion in dairy cattle in the world. The prevalence of Neospora caninum in wild species has been studied since the coyote (Canis latrans), a North American wild canid specie was discovered as definitive host of this parasite. The aim of the present study was to determine the serum prevalence of N. caninum and T. gondii in wild native canids species from Brazil. Serum samples of 25 crab-eating dogs (Cerdocyon thous), five pampas fox (Lycalopex gymnocercus), six bush dogs (Speothos venaticus) e 14 maned wolves (Chrysocyon brachyurus) were tested. The animals were from zoos and sanctuaries from the states of Parana, Santa Catarina, Rio de Janeiro and the Federal District. The total prevalence obtained for N. caninum was 36% (18/50) and for T. gondii was 40% (20/50). The present study demonstrated for the first time the presence of antibodies to N. caninum in bush dogs and the prevalence found was 33,3% (2/6). This study showed the presence of these protozoans in captive wild canids species and to alert about possible contamination sources. PMID:20059860

Mattos, Bianca C; Patrício, Lia L F; Plugge, Nicolle F; Lange, Rogério R; Richartz, Rosária R T B; Dittrich, Rosângela Locatelli

2008-09-01

62

[Disseminated intravascular coagulopathy in a dog with Angiostrongylus vasorum infection].  

PubMed

A 2-year-old female spayed Epagneul-Breton dog was presented with ecchymoses, but an undisturbed general condition. Clinical examination additionally revealed petechia and a haematoma. Travel history included Italy and Denmark. Laboratory abnormalities were moderate thrombocytopenia, prolonged PT, aPTT and TT, and elevated d-dimers. Initial therapy consisted of plasma transfusions, fluids, doxycycline and famotidine administration. Babesiosis, ehrlichiosis, leishmaniosis, dirofilariosis or anaplasmosis could not be confirmed. Abdominal ultrasound was unremarkable, while thoracic radiographs showed a bronchointerstitial pattern. Faecal samples collected over 3 days were positive for Angiostrongylus vasorum after examination using the Baermann lungworm test. The A. vasorum infection was successfully treated with fenbendazole, whereupon thrombocytopenia and prolonged coagulation times were resolved. In regions of low prevalence, an infection with A. vasorum should also be considered as a differential diagnosis in dogs with coagulation abnormalities. Respiratory signs can be absent with this disease. The patient may have acquired the infection abroad or in Germany. PMID:24326880

Kruse, B D; Hartmann, K; Groth, A; Schulz, B; Wehner, A

2013-01-01

63

Angiostrongylus vasorum: Experimental Infection and Larval Development in Omalonyx matheroni.  

PubMed

The susceptibility and suitability of Omalonyx matheroni as an intermediate host of Angiostrongylus vasorum and the characteristics of larval recovery and development were investigated. Mollusks were infected, and from the 3rd to the 25th day after infection, larvae were recovered from groups of 50 individuals. The first observation of L2 was on the 5th day, and the first observation of L3 was on the 10th day. From the 22nd day on, all larvae were at the L3 stadium. Larval recovery varied from 78.2% to 95.2%. We found larval development to be faster in O. matheroni than in Biomphalaria glabrata. Our findings indicate that this mollusk is highly susceptible to A. vasorum. Infective L3 were orally inoculated into a dog, and the prepatent period was 39 days. This is the first study to focus on O. matheroni as an intermediate host of A. vasorum. PMID:21687642

Mozzer, L R; Montresor, L C; Vidigal, T H D A; Lima, W S

2011-01-01

64

Angiostrongylus vasorum: Experimental Infection and Larval Development in Omalonyx matheroni  

PubMed Central

The susceptibility and suitability of Omalonyx matheroni as an intermediate host of Angiostrongylus vasorum and the characteristics of larval recovery and development were investigated. Mollusks were infected, and from the 3rd to the 25th day after infection, larvae were recovered from groups of 50 individuals. The first observation of L2 was on the 5th day, and the first observation of L3 was on the 10th day. From the 22nd day on, all larvae were at the L3 stadium. Larval recovery varied from 78.2% to 95.2%. We found larval development to be faster in O. matheroni than in Biomphalaria glabrata. Our findings indicate that this mollusk is highly susceptible to A. vasorum. Infective L3 were orally inoculated into a dog, and the prepatent period was 39 days. This is the first study to focus on O. matheroni as an intermediate host of A. vasorum. PMID:21687642

Mozzer, L. R.; Montresor, L. C.; Vidigal, T. H. D. A.; Lima, W. S.

2011-01-01

65

Parastrongylus (=Angiostrongylus) cantonensis now endemic in Louisiana wildlife.  

PubMed

Parastrongylus (=Angiostrongylus) cantonensis, a lung worm of rats, was first reported in the United States in 1987, with a probable introduction by infected rats from ships docking in New Orleans, Louisiana, during the mid-1980s. Since then, it has been reported in nonhuman primates and a boy from New Orleans, and in a horse from Picayune, Mississippi, a distance of 87 km from New Orleans. Parastrongylus cantonensis infection is herein reported in a lemur (Varencia variegata rubra) from New Iberia, Louisiana, a distance of 222 km from New Orleans, and in a wood rat (Neotomafloridanus) and in 4 opossums (Didelphis virginiana) from Baton Rouge, Louisiana, a distance of 124 km from New Orleans. The potential of a great variety of gastropods serving as intermediate hosts in Louisiana may pose a threat to wildlife as well as to domesticated animals in the areas where infected Norway rats (Rattus norvegicus) are present. PMID:12435151

Kim, D Y; Stewart, T B; Bauer, R W; Mitchell, M

2002-10-01

66

Entomopathogenic nematodes and insect management  

Technology Transfer Automated Retrieval System (TEKTRAN)

Entomopathogenic nematodes (genera Heterorhabditis, Steinernema, and Neosteinernema) are used as bioinsecticides. The nematodes are ubiquitous and have been isolated in soil of every continent except Antarctica. The nematodes kill insects through a mutualism with a bacterium (Photorhabdus spp. or ...

67

Unique inhibitory cascade pattern of molars in canids contributing to their potential to evolutionary plasticity of diet  

PubMed Central

Developmental origins that guide the evolution of dental morphology and dental formulae are fundamental subjects in mammalian evolution. In a previous study, a developmental model termed the inhibitory cascade model was established. This model could explain variations in relative molar sizes and loss of the lower third molars, which sometimes reflect diet, in murine rodents and other mammals. Here, I investigated the pattern of relative molar sizes (inhibitory cascade pattern) in canids, a taxon exhibiting a wide range of dietary habits. I found that interspecific variation in canid molars suggests a unique inhibitory cascade pattern that differs from that in murine rodents and other previously reported mammals, and that this variation reflects dietary habits. This unique variability in molars was also observed in individual variation in canid species. According to these observations, canid species have greater variability in the relative sizes of first molars (carnassials), which are functionally important for dietary adaptation in the Carnivora. In conclusion, an inhibitory cascade that differs from that in murine rodents and other mammals may have contributed to diverse dietary patterns and to their parallel evolution in canids. PMID:23467478

Asahara, Masakazu

2013-01-01

68

Canid progesterone receptors lack activation function 3 domain-dependent activity.  

PubMed

Progesterone regulates multiple behavioral, physiological, and pathological aspects of female reproductive biology through its two progesterone receptors (PRs), PR-B and the truncated PR-A. PR-B is necessary for mammary gland development in mice and, compared with PR-A, is overall a stronger transactivator of target genes due to an additional activation function 3 (AF3) domain. In dogs, known for their high sensitivity to progesterone-induced mammary cancer, the PR-B function was studied. Canine PR (cPR)-B appeared to contain multiple mutations within AF3 core sequence motifs and lacks N-terminal ligand-independent posttranslational modifications. Consequently, cPR-B has a weak transactivation potential on progesterone-responsive mouse mammary tumor virus-luc and progesterone response element 2-luc reporters transiently transfected in hamster, human, or canine cells and also on known target genes FKBP5 and SGK in doxycycline-inducible, stable transfected cPR-B in canine mammary cells. The cPR-B function was restored to the level of human PR-B by the replacement of canine AF3 domain with the human one. The lack of AF3 domain-dependent transcriptional activity was unique for canids (gray wolf, red fox, and raccoon dog) and not present in closely related caniform species (brown bear, gray seal, and domestic ferret). Despite the limited transactivation potential, canids develop normal mammary glands and frequently mammary tumors. Therefore, these results question the role of PR-B in breast cancer development and may explain unique features of canid reproduction. PMID:23041671

Gracanin, Ana; van Wolferen, Monique E; Sartorius, Carol A; Brenkman, Arjan B; Schoonen, Willem G; Mol, Jan A

2012-12-01

69

Candidatus Bartonella merieuxii, a Potential New Zoonotic Bartonella Species in Canids from Iraq  

PubMed Central

Bartonellae are emerging vector-borne pathogens infecting erythrocytes and endothelial cells of various domestic and wild mammals. Blood samples were collected from domestic and wild canids in Iraq under the United States Army zoonotic disease surveillance program. Serology was performed using an indirect immunofluorescent antibody test for B. henselae, B. clarridgeiae, B. vinsonii subsp. berkhoffii and B. bovis. Overall seroprevalence was 47.4% in dogs (n?=?97), 40.4% in jackals (n?=?57) and 12.8% in red foxes (n?=?39). Bartonella species DNA was amplified from whole blood and representative strains were sequenced. DNA of a new Bartonella species similar to but distinct from B. bovis, was amplified from 37.1% of the dogs and 12.3% of the jackals. B. vinsonii subsp. berkhoffii was also amplified from one jackal and no Bartonella DNA was amplified from foxes. Adjusting for age, the odds of dogs being Bartonella PCR positive were 11.94 times higher than for wild canids (95% CI: 4.55–31.35), suggesting their role as reservoir for this new Bartonella species. This study reports on the prevalence of Bartonella species in domestic and wild canids of Iraq and provides the first detection of Bartonella in jackals. We propose Candidatus Bartonella merieuxii for this new Bartonella species. Most of the Bartonella species identified in sick dogs are also pathogenic for humans. Therefore, seroprevalence in Iraqi dog owners and bacteremia in Iraqi people with unexplained fever or culture negative endocarditis requires further investigation as well as in United States military personnel who were stationed in Iraq. Finally, it will also be essential to test any dog brought back from Iraq to the USA for presence of Bartonella bacteremia to prevent any accidental introduction of a new Bartonella species to the New World. PMID:23029597

Chomel, Bruno B.; McMillan-Cole, Audrey C.; Kasten, Rickie W.; Stuckey, Matthew J.; Sato, Shingo; Maruyama, Soichi; Diniz, Pedro P. V. P.; Breitschwerdt, Edward B.

2012-01-01

70

Molecular genetics of the most endangered canid: the Ethiopian wolf Canis simensis.  

PubMed

The world's most endangered canid is the Ethiopian wolf Canis simensis, which is found in six isolated areas of the Ethiopian highlands with a total population of no more than 500 individuals. Ethiopian wolf populations are declining due to habitat loss and extermination by humans. Moreover, in at least one population, Ethiopian wolves are sympatric with domestic dogs, which may hybridize with them, compete for food, and act as disease vectors. Using molecular techniques, we address four questions concerning Ethiopian wolves that have conservation implications. First, we determine the relationships of Ethiopian wolves to other wolf-like canids by phylogenetic analysis of 2001 base pairs of mitochondrial DNA (mtDNA) sequence. Our results suggest that the Ethiopian wolf is a distinct species more closely related to gray wolves and coyotes than to any African canid. The mtDNA sequence similarity with gray wolves implies that the Ethiopian wolf may hybridize with domestic dogs, a recent derivative of the gray wolf. We examine this possibility through mtDNA restriction fragment analysis and analysis of nine microsatellite loci in populations of Ethiopian wolves. The results imply that hybridization has occurred between female Ethiopian wolves and male domestic dogs in one population. Finally, we assess levels of variability within and between two Ethiopian wolf populations. Although these closely situated populations are not differentiated, the level of variability in both is low, suggesting long-term effective population sizes of less than a few hundred individuals. We recommend immediate captive breeding of Ethiopian wolves to protect their gene pool from dilution and further loss of genetic variability. PMID:7921357

Gottelli, D; Sillero-Zubiri, C; Applebaum, G D; Roy, M S; Girman, D J; Garcia-Moreno, J; Ostrander, E A; Wayne, R K

1994-08-01

71

Artificial insemination in canids: a useful tool in breeding and conservation.  

PubMed

Artificial insemination (AI) and semen freezing have become services available to dog owners worldwide, and the demand for services to freeze semen is increasing. In other canids such as the fox, the fur industry utilizes fresh or frozen semen to artificially inseminate vixens to produce pelts. Clearly, AI facilitates the use of a male to sire several females by diluting the ejaculate, increases breeding hygiene, and allows crossing between species with slightly different breeding seasons. The African wild dog (Lycaon pictus) is currently considered by the World Conservation Union (IUCN) as one of most endangered canids. In captive populations of African wild dogs, semen has been frozen with encouraging results, using a standard cryopreservation protocol for domestic dogs, but successful AI has not been reported. In wolves, there is one report regarding the live birth of an offspring after intravaginal AI of a deslorelin-induced estrous female. In 2005, three Mexican gray wolf females were artificially bred by intrauterine insemination with freshly collected semen from unrelated males, and all females whelped. Artificial insemination may be vaginal, intrauterine or intratubal, and the semen may be fresh, fresh and chilled (diluted), or frozen-thawed, and the source of semen may be epididymal or ejaculated. In the domestic dog, the results are good to excellent for AI with all three types of processed semen when the source is ejaculated semen, whereas epididymal sperm still yields poorer results. Species differences in female physiology, as well as differences in the cryotolerance of the sperm from various canid species, warrant further research and development. PMID:18947865

Thomassen, R; Farstad, W

2009-01-01

72

Wild canids as sentinels of ecological health: a conservation medicine perspective  

PubMed Central

The extinction of species across the globe is accelerating, directly or indirectly due to human activities. Biological impoverishment, habitat fragmentation, climate change, increasing toxification, and the rapid global movement of people and other living organisms have worked synergistically to diminish ecosystem function. This has resulted in unprecedented levels of disease emergence, driven by human-induced environmental degradation, which poses a threat to the survival and health of biodiversity. The emerging discipline of conservation medicine addresses these concerns through the following entities: humans; global climate; habitat destruction and alteration; biodiversity, including wildlife populations; domestic animals; and pathogens, parasites and pollutants. Furthermore, conservation medicine focuses on explicit linkages between these entities. As a crisis discipline, the usefulness of conservation medicine ultimately will depend on its applicability to solving problems. The perspectives and scientific findings of conservation medicine provide input into biomedical education; and policy and management of ecosystems, habitats and imperiled species. A sentinel species is one that has presented itself, or has been selected, to provide insight into the state (health) of an ecosystem, based on user-defined (e.g., researchers, conservationists or policymakers) objectives (e.g., disease, parasites, toxics, climate change, habitat destruction), coupled with the utility and vulnerability of this species to the perceived stress. The scientific information generated by the sentinel species should empower stakeholders and decision-makers to take mitigative action or support predictive capabilities; the "utility" of the species selected should consider its value and relevance to conservationists and to society at large (e.g., education and outreach; social sciences). Wild canids may serve as excellent sentinel species of emerging canine vector-borne diseases. Several canine vector-borne diseases or antibodies to these pathogens have been identified in wild canids including visceral leishmaniosis, Lyme disease, heartworm, hepatozoonosis and anaplasmosis to name a few. These reports are relatively recent as they relate to wildlife-domestic animal interactions, globalisation, translocations, habitat fragmentation and climate change. These pathogens and their relationship to wild canids are described herein. Further research needs to be performed to elucidate the role of the 36 extant species of wild canids in the epidemiology of canine vector-borne diseases. PMID:19426446

Aguirre, A Alonso

2009-01-01

73

Presence of antibotulinum neurotoxin antibodies in selected wild canids in Israel.  

PubMed

Serum samples from 35 golden jackals (Canis aureus syriacus), eight wolves (Canis lupus), and four red foxes (Vulpes vulpes) from various regions of Israel were collected during the years 2001-04 and tested for antibodies to Clostridium botulinum neurotoxin (BoNT) types C and D. Antibodies against BoNT types C and D were detected in 10 (29%) and in 3 (9%) of 35 golden jackals, respectively, using enzyme-linked immunosorbent assay. This report describes detection of anti BoNT antibodies in wild canids other than coyotes (Canis latrans) for the first time and demonstrates that C. botulinum type C is prevalent in Israel. PMID:17699099

Steinman, Amir; Millet, Neta; Frenkel, Chana; King, Roni; Shpigel, Nahum Y

2007-07-01

74

Cross-reactions of sera from dogs infected with Angiostrongylus vasorum in commercially available Dirofilaria immitis test kits  

PubMed Central

Background Dirofilaria immitis and Angiostrongylus vasorum are both important potentially fatal canine nematodes with overlapping endemic areas, especially in Europe. The preadult and adult stages of both species are living in the Arteria pulmonalis and the right heart, and diagnostically detectable circulating parasite antigens have been demonstrated for both species. For the detection of D. immitis infections, a variety of commercial tests have been developed, however, they have not been evaluated for cross-reactions against circulating antigens of A. vasorum. Methods In this study, potential cross-reactions of sera from 16 dogs, which were experimentally infected with A. vasorum and which had circulating antigens as confirmed by a species-specific ELISA, were evaluated for the detection of A. vasorum antigen in six commercially available D. immitis test kits. Results In three fast tests (Witness® Dirofilaria, SensPERT® Canine Heartworm, SNAP® 4Dx® Plus), all sera were negative. One fast membrane ELISA (SNAP® HTWM RT Test) was positive with four sera (25%), and one serum delivered a non-valid result twice. In the PetChek® HTWM PF Test, depending on the interpretation protocol, 5 or 8 dogs (31.2 – 50%) were positive. With the DiroCHEK®-ELISA, a single A. vasorum-infected dog (6.2%) tested positive. Conclusions Due to potential cross-reactions with A. vasorum in commercially available test kits for the detection of D. immitis antigen, the simultaneous use of highly specific diagnostic methods for the differentiation of these two canine heart worms is recommended. PMID:23148786

2012-01-01

75

Human parasitic meningitis caused by Angiostrongylus cantonensis infection in Taiwan.  

PubMed

The major cause of eosinophilic meningitis in Taiwan is Angiostrongylus cantonensis. Humans are infected by ingesting terrestrial and freshwater snails and slugs. In 1998 and 1999, two outbreaks of eosinophilic meningitis caused by A. cantonensis infection were reported among 17 adult male immigrant Thai laborers who had eaten raw golden apple snails (Pomacea canaliculata). Another outbreak associated with consuming a health drink consisting of raw vegetable juice was reported in 2001. These adult cases differed from reports in the 1970s and 1980s, in which most of the cases were in children. With improvements in public health and education of foreign laborers, there have since been only sporadic cases in Taiwan. Review of clinical research indicates inconsistent association of Magnetic Resonance Imaging (MRI) results with clinical features of eosinophilic meningitis. MRI features were nonspecific but there was an association between the presence of high brain MRI signal intensities and severity of peripheral and cerebrospinal fluid (CSF) eosinophilia. Inflammatory markers have been identified in the CSF of patients with eosinophilic meningitis caused by A. cantonensis infection, and vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and the matrix metalloproteinase system may be associated with blood-brain barrier disruption. Eosinophilic meningitis caused by A. cantonensis infection is not a reportable disease in Taiwan. It is important that a public advisory and education program be developed to reduce future accidental infection. PMID:23901378

Tsai, Hung-Chin; Chen, Yao-Shen; Yen, Chuan-Min

2013-06-01

76

Identification and characterization of an asparaginyl endopeptidase from Angiostrongylus cantonensis.  

PubMed

Asparaginyl endopeptidase, also known as legumain, is a family of cysteine proteases in many organisms. In this study, an asparaginyl endopeptidase (Ac-AEP) was identified from the cDNA library of Angiostrongylus cantonensis. The full-length of Ac-AEP was determined to be 1,472 bp with an open reading frame of 1,341 bp encoding a putative protein with 446 amino acids. This putative protein was determined to have 37-65% identity in the amino acid sequences of the asparaginyl endopeptidases of other parasitic helminths. By real-time quantitative PCR analysis, Ac-AEP was revealed to be more abundantly expressed in the female adult worms than in other development stages. A recombinant asparaginyl endopeptidase (rAc-AEP) was then produced by a Pichia pastoris expression system. Posttranslational modification was shown to occur via N-linked glycosylation in this recombinant enzyme. The proteolytic activity of rAc-AEP was inhibited by iodoacetamide but not affected by E64, pepatain A, AEBSF, and EDTA. Moreover, the purified rAc-AEP was recognized by IgG in serum samples from BALB/c or ICR mice with A. cantonensis infection and patients with eosinophilic meningitis. These findings indicate that the rAc-AEP may have the potential for detecting A. cantonensis infection. PMID:24696276

Chang, Shih-Hsin; Chen, Kuang-Yao; Wang, Lian-Chen

2014-06-01

77

A Pathological Late Pleistocene canid from San Sidero (Italy): implications for social- and feeding-behaviour  

NASA Astrophysics Data System (ADS)

Evidence of diseases on vertebrate fossil bones can provide detailed information on many aspects of extinct animals. This study focused on pathological craniodental remains (left maxilla and dentary) referred to the canid Cuon alpinus unearthed from a Late Pleistocene karst filling deposit at San Sidero (Apulia, southern Italy). These fossils show clear evidence of a chronic periodontitis that caused the animal's death. Clinical diagnosis of the disease and the timing of its development have been defined on the basis of a veterinary odontostomatology approach, in addition to radiographic and tomographic techniques. From the initiation of the infection until death, a time span of at least 6 months occurred, and three main steps have been defined: (1) the bacterial infections of the buccal cavity turning into severe periodontitis, (2) the fracture of the lower carnassial and (3) the loss of teeth due to the worsening infection that deformed and/or eroded maxillary and mandibular bones and enlarged alveoli. The analysis of the palaeopathology also provides information about the biomechanics of the bite, on the feeding behaviour and on the relationships of injured members in a pack of Late Pleistocene canids.

Iurino, Dawid Adam; Fico, Rosario; Petrucci, Mauro; Sardella, Raffaele

2013-03-01

78

DNA extraction from hair shafts of wild Brazilian felids and canids.  

PubMed

Wild felids and canids are usually the main predators in the food chains where they dwell and are almost invisible to behavior and ecology researchers. Due to their grooming behavior, they tend to swallow shed hair, which shows up in the feces. DNA found in hair shafts can be used in molecular studies that can unravel, for instance, genetic variability, reproductive mode and family structure, and in some species, it is even possible to estimate migration and dispersion rates in given populations. First, however, DNA must be extracted from hair. We extracted successfully and dependably hair shaft DNA from eight wild Brazilian felids, ocelot, margay, oncilla, Geoffroy's cat, pampas cat, jaguarundi, puma, and jaguar, as well as the domestic cat and from three wild Brazilian canids, maned wolf, crab-eating fox, and hoary fox, as well as the domestic dog. Hair samples came mostly from feces collected at the São Paulo Zoo and were also gathered from non-sedated pet or from recently dead wild animals and were also collected from museum specimens. Fractions of hair samples were stained before DNA extraction, while most samples were not. Our extraction protocol is based on a feather DNA extraction technique, based in the phenol:chloroform:isoamyl alcohol general method, with proteinase K as digestive enzyme. PMID:21174262

Alberts, C C; Ribeiro-Paes, J T; Aranda-Selverio, G; Cursino-Santos, J R; Moreno-Cotulio, V R; Oliveira, A L D; Porchia, B F M M; Santos, W F; Souza, E B

2010-01-01

79

Fatal Canid Herpesvirus 1 Respiratory Infections in 4 Clinically Healthy Adult Dogs.  

PubMed

Four healthy adult dogs (Golden Retrievers aged 6 years and 9 years, Dalmatian aged 13 years, and Mastiff aged 5 years) developed clinical signs of acute respiratory disease and died within 2 to 7 days of onset of clinical signs. The lungs of the 3 dogs submitted for necropsy were diffusely and severely reddened due to hyperemia and hemorrhage. Microscopic lesions in all dogs were suggestive of acute viral or toxic respiratory damage and varied from acute severe fibrinonecrotic or hemorrhagic bronchopneumonia to fibrinous or necrotizing bronchointerstitial pneumonia. Necropsied dogs also had hemorrhagic rhinitis and tracheitis with necrosis. Virus isolation, transmission electron microscopy, and polymerase chain reaction were used to confirm the presence of canid herpesvirus 1 (CaHV-1) in the lung samples of these dogs. Lung tissues were negative for influenza A virus, canine distemper virus, canine parainfluenza virus, canine respiratory coronavirus, and canine adenovirus 2. Canid herpesvirus 1 has been isolated from cases of acute infectious respiratory disease in dogs but has only rarely been associated with fatal primary viral pneumonia in adult dogs. The cases in the current report document lesions observed in association with CaHV-1 in 4 cases of fatal canine herpesvirus pneumonia in adult dogs. PMID:25358536

Kumar, S; Driskell, E A; Cooley, A J; Jia, K; Blackmon, S; Wan, X-F; Uhl, E W; Saliki, J T; Sanchez, S; Krimer, P M; Hogan, R J

2014-10-30

80

Parasites of domestic and wild canids in the region of Serra do Cipó National Park, Brazil.  

PubMed

Over recent decades, diseases have been shown to be important causes of extinctions among wild species. Greater emphasis has been given to diseases transmitted by domestic animals, which have been increasing in numbers in natural areas, along with human populations. This study had the aim of investigating the presence of intestinal helminths in wild canids (maned wolf, Chrysocyon brachyurus, and crab-eating fox, Cerdocyon thous) in the Serra do Cipó National Park (43-44º W and 19-20º S) and endo and ectoparasites of domestic dogs in the Morro da Pedreira Environmental Protection Area (an area surrounding the National Park). The Serra do Cipó is located in the state of Minas Gerais, Brazil. Among the enteroparasites found in domestic and wild canids, the following taxons were identified: Ancylostomidae, Trichuridae, Toxocara sp., Spirocerca sp., Physaloptera sp., Strongyloides sp., Cestoda, Dipylidium caninum, Diphyllobothriidae, Hymenolepidae, Anoplocephalidae, Trematoda, Acanthocephala and Isospora sp. Domestic dogs were positive for leishmaniasis and Babesia canis in serological tests. Among the ectoparasites, Rhipicephalus sanguineus, Amblyomma cajennense and Ctenocephalides felis felis were observed in domestic dogs. Variations in the chaetotaxy of the meta-episternum and posterior tibia were observed in some specimens of C. felis felis. PMID:23070438

Santos, Juliana Lúcia Costa; Magalhães, Noele Borges; Dos Santos, Hudson Andrade; Ribeiro, Raul Rio; Guimarães, Marcos Pezzi

2012-01-01

81

A genome-wide perspective on the evolutionary history of enigmatic wolf-like canids.  

PubMed

High-throughput genotyping technologies developed for model species can potentially increase the resolution of demographic history and ancestry in wild relatives. We use a SNP genotyping microarray developed for the domestic dog to assay variation in over 48K loci in wolf-like species worldwide. Despite the high mobility of these large carnivores, we find distinct hierarchical population units within gray wolves and coyotes that correspond with geographic and ecologic differences among populations. Further, we test controversial theories about the ancestry of the Great Lakes wolf and red wolf using an analysis of haplotype blocks across all 38 canid autosomes. We find that these enigmatic canids are highly admixed varieties derived from gray wolves and coyotes, respectively. This divergent genomic history suggests that they do not have a shared recent ancestry as proposed by previous researchers. Interspecific hybridization, as well as the process of evolutionary divergence, may be responsible for the observed phenotypic distinction of both forms. Such admixture complicates decisions regarding endangered species restoration and protection. PMID:21566151

vonHoldt, Bridgett M; Pollinger, John P; Earl, Dent A; Knowles, James C; Boyko, Adam R; Parker, Heidi; Geffen, Eli; Pilot, Malgorzata; Jedrzejewski, Wlodzimierz; Jedrzejewska, Bogumila; Sidorovich, Vadim; Greco, Claudia; Randi, Ettore; Musiani, Marco; Kays, Roland; Bustamante, Carlos D; Ostrander, Elaine A; Novembre, John; Wayne, Robert K

2011-08-01

82

The potential for gamete recovery from non-domestic canids and felids.  

PubMed

Species are becoming extinct at a rate 100 times the natural background rates. Considering all mammalian orders, 24% of all Carnivora species are threatened. The goal of carnivore conservation is to reverse the decline in populations and to secure remaining populations in ways that will assure enduring public support. In this context, biotechnology is a tool with tremendous potential for assisting the conservation of endangered canid and felid species. As the first step for biotechnology development is the gamete obtainment, this review will discuss the potential of gamete recovery from non-domestic canids and felids, based on learning how to apply these procedures in the domestic carnivores. Thus, electroejaculation and obtaining both epidydimal spermatozoon and spermatogonial germ cells are indicated as techniques for male gametes recovery. In the female gametes retrieval, different methods for oocyte recovery from both antral and preantral follicles, and the possibility for ovarian tissue transplantation are discussed. Furthermore, the study discusses the responsibilities involved in the use of assisted reproduction in endangered species conservation. PMID:14749057

Silva, Alexandre R; Morato, Ronaldo G; Silva, Lúcia D M

2004-03-01

83

Natural infection of the wild canid, Cerdocyon thous, with the piroplasmid Rangelia vitalii in Brazil.  

PubMed

Canine rangeliosis, caused by the piroplasmid protozoon Rangelia vitalii, is currently recognized as a reemerging disease that affects domestic dogs in Brazil. In the present study, piroplasmid infection was searched in wild canids (20 Cerdocyon thous and 4 Lycalopex gymnocercus) in Brazil. Molecular analysis, based on PCR and DNA sequencing of a portion of the 18S rRNA gene, revealed that 30% (6/20) C. thous were infected by R. vitalii. Blood and bone marrow samples from one of the R. vitalii-infected C. thous were inoculated into a domestic dog, which developed clinical rangeliosis that was confirmed by molecular tests. However, the C. thous donor showed no clinical, hematological or biochemical alterations, even though its R. vitalii infection status was confirmed for at least 80 days. These observations suggest that R. vitalii is not as highly pathogenic for C. thous as it is for domestic dogs. Phylogenetic analysis inferred by the 18S rRNA gene placed R. vitalii embedded in the clade 'Babesia sensu stricto', consisting of a number of species that represent truly the genus Babesia. It is proposed that the species R. vitalii should be transferred to the genus Babesia. The present study expands our knowledge on the natural history of R. vitalii, suggesting that it might have a natural cycle involving the wild canid C. thous. Further studies are needed to confirm that C. thous is a natural reservoir of R. vitalii in Brazil. PMID:24685025

Soares, João F; Dall'Agnol, Bruno; Costa, Francisco B; Krawczak, Felipe S; Comerlato, Alexandra T; Rossato, Bruna C D; Linck, Camila M; Sigahi, Eduardo K O; Teixeira, Rodrigo H F; Sonne, Luciana; Hagiwara, Mitika K; Gregori, Fabio; Vieira, Maria Isabel B; Martins, João R; Reck, José; Labruna, Marcelo B

2014-05-28

84

Detection of Echinococcus granulosus coproantigens in Australian canids with natural or experimental infection.  

PubMed

Coproparasitological and purging methods for diagnosing canids infected with the intestinal helminth Echinococcus granulosus, an important zoonotic parasite, are unreliable. Detection of coproantigens in feces of infected dogs by enzyme-linked immunosorbent assay (ELISA) is suitable for detecting patent and prepatent infections with a high degree of sensitivity and specificity. In the present study, natural and experimental infections in domestic and wild Australian canids were investigated using a coproantigen capture ELISA. Experimental infection of dogs with E. granulosus was detected at between 14 and 22 days postinfection (PI), and optical density (OD) values remained high until termination of experiments 35 days PI. After chemotherapy, coproantigen levels in infected dogs dropped rapidly, becoming negative 2-4 days after treatment. In experimentally infected red foxes (Vulpes vulpes), the coproantigen excretion profile was different, with ELISA OD levels peaking 15-17 days PI, then falling to low or undetectable levels by 30 days PI. Coproantigens were detected in the feces of naturally infected Australian wild dogs (dingoes, dingo/domestic dog hybrids) with infection levels ranging between 2 worms and 42,600. Preliminary data on the stability of coproantigen in dog feces exposed to environmental conditions indicated that there was no change in antigenicity over 6 days. The results suggest the coproantigen ELISA could be successfully used to monitor E. granulosus prevalence rates in Australian domestic dogs, foxes, and wild dogs. PMID:10701577

Jenkins, D J; Fraser, A; Bradshaw, H; Craig, P S

2000-02-01

85

A genome-wide perspective on the evolutionary history of enigmatic wolf-like canids  

PubMed Central

High-throughput genotyping technologies developed for model species can potentially increase the resolution of demographic history and ancestry in wild relatives. We use a SNP genotyping microarray developed for the domestic dog to assay variation in over 48K loci in wolf-like species worldwide. Despite the high mobility of these large carnivores, we find distinct hierarchical population units within gray wolves and coyotes that correspond with geographic and ecologic differences among populations. Further, we test controversial theories about the ancestry of the Great Lakes wolf and red wolf using an analysis of haplotype blocks across all 38 canid autosomes. We find that these enigmatic canids are highly admixed varieties derived from gray wolves and coyotes, respectively. This divergent genomic history suggests that they do not have a shared recent ancestry as proposed by previous researchers. Interspecific hybridization, as well as the process of evolutionary divergence, may be responsible for the observed phenotypic distinction of both forms. Such admixture complicates decisions regarding endangered species restoration and protection. PMID:21566151

vonHoldt, Bridgett M.; Pollinger, John P.; Earl, Dent A.; Knowles, James C.; Boyko, Adam R.; Parker, Heidi; Geffen, Eli; Pilot, Malgorzata; Jedrzejewski, Wlodzimierz; Jedrzejewska, Bogumila; Sidorovich, Vadim; Greco, Claudia; Randi, Ettore; Musiani, Marco; Kays, Roland; Bustamante, Carlos D.; Ostrander, Elaine A.; Novembre, John; Wayne, Robert K.

2011-01-01

86

A strategic approach to mitigating the impacts of wild canids: proposed activities of the Invasive Animals Cooperative Research Centre  

Microsoft Academic Search

Wild canids (wild dogs and European red foxes) cause substantial losses to Australian livestock industries and environmental values. Both species are actively managed as pests to livestock production. Contemporaneously, the dingo proportion of the wild dog population, being considered native, is protected in areas designated for wildlife conservation. Wild dogs particularly affect sheep and goat production because of the behavioural

P. J. S. Fleming; L. R. Allen; S. J. Lapidge; A. Robley; G. R. Saunders; P. C. Thomson

2006-01-01

87

Canine and feline cardiopulmonary parasitic nematodes in Europe: emerging and underestimated  

PubMed Central

Cardiopulmonary nematodes of dogs and cats cause parasitic diseases of central relevance in current veterinary practice. In the recent past the distribution of canine and feline heartworms and lungworms has increased in various geographical areas, including Europe. This is true especially for the metastrongyloids Aelurostrongylus abstrusus, Angiostrongylus vasorum and Crenosoma vulpis, the filarioid Dirofilaria immitis and the trichuroid Eucoleus aerophilus (syn. Capillaria aerophila). The reasons of this emergence are little known but many drivers such as global warming, changes in vector epidemiology and movements in animal populations, may be taken into account. The purpose of this article is to review the knowledge of the most important heartworm and lungworm infections of dogs and cats in Europe. In particular recent advances in epidemiology, clinical and control are described and discussed. PMID:20653938

2010-01-01

88

New insights onto cardiopulmonary nematodes of dogs in Sardinia, Italy.  

PubMed

Dog heartworms Angiostrongylus vasorum and Dirofilaria immitis cause severe parasitological diseases; the importance of these parasitosis is growing due to their health impact on animals, the possible zoonotic implications and the recent spreading across several European countries and previously non-endemic areas. The aim of this study is to update the epidemiological scenario of cardiopulmonary nematodes A. vasorum and D. immitis in dogs of Sardinia island and to perform a morphological identification of larvae by the use of the Baermann and Knott techniques respectively and the molecular characterization of the mitochondrial cytochrome c oxidase subunit I (cox1) and the second ribosomal transcribed spacer region (ITS-2) of larvae L1 of A. vasorum. In the present study, 3.4% (5/146) of dogs resulted positive at Baermann technique for A. vasorum while 8.9% (61/684) to D. immitis. If on one side A. vasorum can be considered an emerging parasite in Sardinia, the parasitic pressure and the risk of infection for D. immitis in the island seems to be increased compared with the recent past. PMID:24525757

Pipia, A P; Varcasia, A; Tosciri, G; Seu, S; Manunta, M L; Mura, M C; Sanna, G; Tamponi, C; Brianti, E; Scala, A

2014-04-01

89

Immunological diagnosis of human angiostrongyliasis due to Angiostrongylus cantonensis (Nematoda: Angiostrongylidae).  

PubMed

Angiostrongylus cantonensis-associated eosinophilic meningitis in humans has been commonly reported worldwide. However parasitologically confirmed cases are not common, as the parasite has been recovered only infrequently from the cerebrospinal fluid of patients. The potential value of immunodiagnosis is therefore self-evident. Immunological tests can also help in the differential diagnosis of parasitic (particularly helminths) infections that cause eosinophilic meningitis. This paper summarizes the state of and advances in the immunological diagnosis of human angiostrongyliasis due to Angiostrongylus (= Parastrongylus) cantonensis. A specific antigen is available for the definitive diagnosis and unequivocal differentiation of eosinophilic meningitis due to helminth infections. Rapid diagnostic kits based on dot-blot ELISA have been developed and have proved to be simple, effective, and economical for field use. PMID:19117782

Eamsobhana, Praphathip; Yong, Hoi Sen

2009-07-01

90

Clinical Aspects of Eosinophilic Meningitis and Meningoencephalitis caused by Angiostrongylus cantonensis, the Rat Lungworm  

PubMed Central

Angiostrongylus Eosinophilic Meningitis is caused by human infection with larvae of the rat lungworm, Angiostrongylus cantonensis. The clinical presentation includes a spectrum of disease, from meningitis through radiculitis, cranial nerve abnormalities, ataxia, encephalitis, coma, and rarely death. The condition is diagnosed by recognizing the triad of: the clinical syndrome, eosinophils in the cerebrospinal fluid or blood, and exposure history. A history of eating raw or poorly cooked snails is classic, but ingestion of other intermediate hosts or unwashed produce (such as lettuce) harboring hosts is not uncommon. Several serologic tests exist but none has yet been fully validated. There is good evidence that a 2 week course of high dose corticosteroids shortens the duration and severity of symptoms. There is somewhat weaker evidence that albendazole reduces symptoms. The combination of prednisolone and albendazole is being used more commonly for treatment. Some suggestions for future research are given. PMID:23901382

Johnson, Stuart

2013-01-01

91

Rupture of the thoracic aorta associated with experimental Angiostrongylus vasorum infection in a dog  

PubMed Central

This note describes the sudden death of a dog by the rupture of the thoracic aorta caused by the presence of Angiostrongylus vasorum. A female mongrel canine with a history of weight loss and exhaustion died two hours after clinical examination. At necropsy, performed one hour after death, showed the presence of clotted blood in the thoracic cavity. Haemothorax was diagnosed. The thoracic aorta wall was thin, congested and an abnormal hole in the wall was detected approximately 0.5 cm from the entrance to the diaphragm. From clotted blood collected from the thoracic cavity, 224 first stage larvae (L1) and 15 adults of Angiostrongylus vasorum were recovered alive. Also, from a blood clot found in the aorta, four adult females and 47 L1 larvae were recovered alive. Possibly, this parasite was responsible for the aortic rupture and death of the animal. PMID:22550632

Mozzer, L.R.; Lima, W.S.

2012-01-01

92

Serologic evidence of Leishmania infection in free-ranging wild and domestic canids around a Brazilian National Park.  

PubMed

Transmission of disease between wildlife, domestic animals, and humans is of great concern to conservation issues and public health. Here we report on the prevalence of anti-Leishmania sp. antibodies in 21 wild canids (7 Chrysocyon brachyurus, 12 Cerdocyon thous, and 2 Lycalopex vetulus) and 74 free domestic dogs (Canis familiaris) sampled around the Serra do Cipó National Park. In dogs, the apparent prevalence was 8.1% and in wild canids it was 19% (2 crab-eating foxes, C. thous, and 2 maned wolves, C. brachyurus). Management of the domestic dog population with evaluation of incidence changes in humans and wildlife, and enlightenment on the role of wild reservoirs are essential issues for future action and research. PMID:16699717

Curi, Nelson Henrique de Almeida; Miranda, Ildikó; Talamoni, Sônia A

2006-02-01

93

3D morphometric analysis of fossil canid skulls contradicts the suggested domestication of dogs during the late Paleolithic.  

PubMed

Whether dogs were domesticated during the Pleistocene, when humans were hunter-gatherers, or during the Neolithic, when humans began to form permanent settlements and engage in agriculture, remains controversial. Recently discovered Paleolithic fossil skulls, Goyet dated 31,680 +/- 250?YBP and Eliseevichi MAE 447/5298 dated 13,905 +/- 55?YBP, were previously identified as dogs. However, new genetic studies contradict the identification of these specimens as dogs, questioning the validity of traditional measurements used to morphologically identify canid fossil skulls. We employ 3D geometric morphometric analyses to compare the cranial morphology of Goyet and Eliseevichi MAE to that of ancient and modern dogs and wolves. We demonstrate that these Paleolithic canids are definitively wolves and not dogs. Compared to mesaticephalic (wolf-like breeds) dog skulls, Goyet and Eliseevichi MAE, do not have cranial flexion and the dorsal surface of their muzzles has no concavity near the orbits. Morphologically, these early fossil canids resemble wolves, and thus no longer support the establishment of dog domestication in the Paleolithic. PMID:25654325

Drake, Abby Grace; Coquerelle, Michael; Colombeau, Guillaume

2015-01-01

94

Assessment of the combination of spinosad and milbemycin oxime in preventing the development of canine Angiostrongylus vasorum infections.  

PubMed

Angiostrongylus vasorum is an increasingly reported parasite in Europe that develops in dogs after ingestion of infective third stage larvae (L3) that reside in gastropod molluscs which are needed to complete the parasite's life-cycle. Infection can produce a diversity of clinical signs, determined by involvement of the respiratory, neurological, and/or coagulation system, with a likely fatal outcome in the absence of treatment. Few drugs have been shown to reliably prevent infection, and data on treatment of infections is limited. A controlled, randomized, partially blinded laboratory study was therefore executed to evaluate the efficacy and safety of a combination tablet of spinosad/milbemycin oxime in dogs inoculated with approximately 250 A. vasorum L3. Sixteen healthy nematode free adult dogs were randomly allocated to two study groups of 8 dogs each. Thirty days post inoculation (dpi) all dogs in the fed state were treated: dogs in group B were treated with spinosad and milbemycin oxime at the dose rates of 45-60 mg/kg and 0.75-1.0mg/kg bodyweight, respectively, approximately the lower half portion of the expected full unit dose range; dogs in group A were treated with placebo tablets. All dogs were euthanized and necropsied 56-58 dpi. The heart and lungs were examined to determine the presence of A. vasorum. All placebo group dogs were infected at necropsy with counts ranging from 22 to 98 adult worms and a geometric mean worm count of 55.2. In contrast, the geometric mean worm count in the spinosad/milbemycin oxime group was 0.7 with worm numbers ranging from 0 to 8. The results of this study demonstrate that a single treatment with the tablet combination of spinosad and milbemycin oxime administered 30 dpi provided 98.8% preventive efficacy against development of adult A. vasorum infections. Monthly treatments with spinosad and milbemycin oxime have the potential to prevent the establishment of infections with A. vasorum in dogs. PMID:24269160

Böhm, Claudia; Schnyder, Manuela; Thamsborg, Stig Milan; Thompson, Caryn M; Trout, Candace; Wolken, Sonja; Schnitzler, Beate

2014-01-31

95

Production of entomopathogenic nematodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Production technology is critical for the success of entomopathogenic nematodes (EPNs) in biological control. Production approaches include in vivo and in vitro methods (solid or liquid fermentation). For laboratory use and small scale field experiments, in vivo production of EPNs appears to be th...

96

Serum lipid concentrations in six canid and four ursid species in four zoos.  

PubMed

Serum lipid levels were measured in healthy captive wild canids and ursids, and the values were compared with previously published data. Serum lipid levels were evaluated in blood samples collected from eight African wild dogs (Lycaon pictus), three arctic foxes (Alopex lagopus), nine gray wolves (Canis lupus), four maned wolves (Chrysocyon brachyurus), two Mexican wolves (Canis lupus baleiyi), nine red wolves (Canis rufus), two brown bears (Ursus arctos), six polar bears (Ursus maritimus), six spectacled bears (Tremarctos ornatus), and five sun bears (Ursus malayanus). Samples were analyzed for total cholesterol, triacylglycerides, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol. Although the results showed a great variation among species, circulating lipids appeared especially high, sometimes extremely so, in the spectacled bears, polar bears, sun bears, and maned wolves compared with all other species sampled. The study provides a substantial basis for comparing lipid levels in presumed healthy animals and indicates a need for controlled study of the effects of diet on circulating lipid levels. PMID:15193071

Crissey, Susan D; Ange, Kimberly D; Slifka, Kerri A; Sadler, William; Kahn, Stephen; Ward, Ann M

2004-03-01

97

Evidence of coat color variation sheds new light on ancient canids.  

PubMed

We have used a paleogenetics approach to investigate the genetic landscape of coat color variation in ancient Eurasian dog and wolf populations. We amplified DNA fragments of two genes controlling coat color, Mc1r (Melanocortin 1 Receptor) and CBD103 (canine-?-defensin), in respectively 15 and 19 ancient canids (dogs and wolf morphotypes) from 14 different archeological sites, throughout Asia and Europe spanning from ca. 12 000 B.P. (end of Upper Palaeolithic) to ca. 4000 B.P. (Bronze Age). We provide evidence of a new variant (R301C) of the Melanocortin 1 receptor (Mc1r) and highlight the presence of the beta-defensin melanistic mutation (CDB103-K locus) on ancient DNA from dog-and wolf-morphotype specimens. We show that the dominant K(B) allele (CBD103), which causes melanism, and R301C (Mc1r), the variant that may cause light hair color, are present as early as the beginning of the Holocene, over 10,000 years ago. These results underline the genetic diversity of prehistoric dogs. This diversity may have partly stemmed not only from the wolf gene pool captured by domestication but also from mutations very likely linked to the relaxation of natural selection pressure occurring in-line with this process. PMID:24098367

Ollivier, Morgane; Tresset, Anne; Hitte, Christophe; Petit, Coraline; Hughes, Sandrine; Gillet, Benjamin; Duffraisse, Marilyne; Pionnier-Capitan, Maud; Lagoutte, Laetitia; Arbogast, Rose-Marie; Balasescu, Adrian; Boroneant, Adina; Mashkour, Marjan; Vigne, Jean-Denis; Hänni, Catherine

2013-01-01

98

Soil Nematodes in Terrestrial Ecosystems  

PubMed Central

There has been much work on plant-feeding nematodes, and less on other soil nematodes, their distribution, abundance, intrinsic properties, and interactions with biotic and abiotic factors. Seasonal variation in nematode fauna as a whole is correlated with factors such as moisture, temperature, and plant growth; at each site nematode distribution generally reflects root distribution. There is a positive correlation between average nematode abundance and primary production as controlled by moisture, temperature, nutrients, etc. Soil nematodes, whether bacterial feeders, fungivores, plant feeders, omnivores, or predators, all influence the populations of the organisms they feed on. Although soil trematodes probably contribute less than 1% to soil respiration they may play an important role in nutrient cycling in the soil through their influence on bacterial growth and plant nutrient availability. PMID:19300638

Yeates, G. W.

1979-01-01

99

Factors associated with uterine endometrial hyperplasia and pyometra in wild canids: implications for fertility.  

PubMed

The ability to safely and effectively manage reproduction is central to the success of AZA captive-breeding programs. Although the AZA Wildlife Contraception Center routinely monitors contraceptive safety, there have been no studies that compare the effects of contraceptive use to separation of males from females, the other option for preventing reproduction. We used retrospective medical records and pathology reports submitted by AZA and related facilities for the seven AZA-managed canid species to assess rates of uterine pathology relative to female reproductive life histories. Our results showed that the prevalence of both pyometra and endometrial hyperplasia (EH) was associated not only with treatment with the two most common contraceptives (Suprelorin® and MGA implants) but also with the number of years barren (i.e., not producing a litter and not contracepted). Rates of pyometra and EH were especially high in African painted dogs and red wolves, but lowest in swift and fennec foxes. The number of years producing a litter had a low association, suggesting it could be protective against uterine pathology. A more recently developed Suprelorin® protocol using Ovaban® to prevent the initial stimulation phase, followed by implant removal when reversal is desired, may be a safer contraceptive option. These results concerning the relationship between reproductive management and uterine health have important implications for AZA-managed programs, since the unsustainability of many captive populations may be due at least in part to infertility. Managing a female's reproductive lifespan to optimize or maintain fertility will require a reconsideration of how breeding recommendations are formulated. PMID:23553688

Asa, Cheryl S; Bauman, Karen L; Devery, Sarah; Zordan, Martín; Camilo, Gerardo R; Boutelle, Sally; Moresco, Anneke

2014-01-01

100

A thyroid peroxidase (TPO) mutation in dogs reveals a canid-specific gene structure.  

PubMed

Congenital hypothyroidism with goiter (CHG) occurring as an autosomal recessive disorder is typically due to a defect of thyroid hormone synthesis (aka dyshormonogenesis). Thyroid peroxidase (TPO) is a multifunctional, heme-containing enzyme whose activity is required, and several inactivating TPO mutations causing CHG in humans and dogs have been described. Recently, two half-sib Spanish water dog (SWD) pups were diagnosed with CHG based on clinical signs, endocrine testing, and thyroid histology. TPO enzyme activity was absent, and immuno-cross-reactive TPO was undetectable in affected-dog thyroid tissue. A single guanosine insertion was observed in the first exon of the affected-dog TPO cDNA at a site not previously thought to be within the coding sequence. The insertion allele segregated with the deduced disease allele in the SWD breed and was not observed in unrelated dogs of various breeds. Comparison of the insertion site (an 8-nt poly-G tract) with the orthologous sequences of other mammalian reference genomes revealed that the octa-G tract obliterated the intron 1 splice acceptor site and the exon 2 translation initiation codon found at that position in other species. An in-frame ATG in strong Kozak consensus context was observed in the normal dog sequence 12 codons 5' of the usual mammalian start site, suggesting that dogs have lost the noncoding exon 1 demonstrated in human and mouse. A survey of TPO sequences in other carnivore species indicates that the poly-G tract necessitating an alternative translation initiation site is a canid-specific feature. PMID:23223904

Fyfe, John C; Lynch, Mary; Olsen, Jayme; Lou?r, Eric

2013-04-01

101

An evaluation of the PCR-RFLP technique to aid molecular-based monitoring of felids and canids in India  

PubMed Central

Background The order Carnivora is well represented in India, with 58 of the 250 species found globally, occurring here. However, small carnivores figure very poorly in research and conservation policies in India. This is mainly due to the dearth of tested and standardized techniques that are both cost effective and conducive to small carnivore studies in the field. In this paper we present a non-invasive genetic technique standardized for the study of Indian felids and canids with the use of PCR amplification and restriction enzyme digestion of scat collected in the field. Findings Using existing sequences of felids and canids from GenBank, we designed primers from the 16S rRNA region of the mitochondrial genome and tested these on ten species of felids and five canids. We selected restriction enzymes that would cut the selected region differentially for various species within each family. We produced a restriction digestion profile for the potential differentiation of species based on fragment patterns. To test our technique, we used felid PCR primers on scats collected from various habitats in India, representing varied environmental conditions. Amplification success with field collected scats was 52%, while 86% of the products used for restriction digestion could be accurately assigned to species. We verified this through sequencing. A comparison of costs across the various techniques currently used for scat assignment showed that this technique was the most practical and cost effective. Conclusions The species-specific key developed in this paper provides a means for detailed investigations in the future that focus on elusive carnivores in India and this approach provides a model for other studies in areas of Asia where many small carnivores co-occur. PMID:20525407

2010-01-01

102

Water Developments and Canids in Two North American Deserts: A Test of the Indirect Effect of Water Hypothesis  

PubMed Central

Anthropogenic modifications to landscapes intended to benefit wildlife may negatively influence wildlife communities. Anthropogenic provisioning of free water (water developments) to enhance abundance and distribution of wildlife is a common management practice in arid regions where water is limiting. Despite the long-term and widespread use of water developments, little is known about how they influence native species. Water developments may negatively influence arid-adapted species (e.g., kit fox, Vulpes macrotis) by enabling water-dependent competitors (e.g., coyote, Canis latrans) to expand distribution in arid landscapes (i.e., indirect effect of water hypothesis). We tested the two predictions of the indirect effect of water hypothesis (i.e., coyotes will visit areas with free water more frequently and kit foxes will spatially and temporally avoid coyotes) and evaluated relative use of free water by canids in the Great Basin and Mojave Deserts from 2010 to 2012. We established scent stations in areas with (wet) and without (dry) free water and monitored visitation by canids to these sites and visitation to water sources using infrared-triggered cameras. There was no difference in the proportions of visits to scent stations in wet or dry areas by coyotes or kit foxes at either study area. We did not detect spatial (no negative correlation between visits to scent stations) or temporal (no difference between times when stations were visited) segregation between coyotes and kit foxes. Visitation to water sources was not different for coyotes between study areas, but kit foxes visited water sources more in Mojave than Great Basin. Our results did not support the indirect effect of water hypothesis in the Great Basin or Mojave Deserts for these two canids. PMID:23844097

Hall, Lucas K.; Larsen, Randy T.; Knight, Robert N.; Bunnell, Kevin D.; McMillan, Brock R.

2013-01-01

103

Water developments and canids in two North American deserts: a test of the indirect effect of water hypothesis.  

PubMed

Anthropogenic modifications to landscapes intended to benefit wildlife may negatively influence wildlife communities. Anthropogenic provisioning of free water (water developments) to enhance abundance and distribution of wildlife is a common management practice in arid regions where water is limiting. Despite the long-term and widespread use of water developments, little is known about how they influence native species. Water developments may negatively influence arid-adapted species (e.g., kit fox, Vulpes macrotis) by enabling water-dependent competitors (e.g., coyote, Canis latrans) to expand distribution in arid landscapes (i.e., indirect effect of water hypothesis). We tested the two predictions of the indirect effect of water hypothesis (i.e., coyotes will visit areas with free water more frequently and kit foxes will spatially and temporally avoid coyotes) and evaluated relative use of free water by canids in the Great Basin and Mojave Deserts from 2010 to 2012. We established scent stations in areas with (wet) and without (dry) free water and monitored visitation by canids to these sites and visitation to water sources using infrared-triggered cameras. There was no difference in the proportions of visits to scent stations in wet or dry areas by coyotes or kit foxes at either study area. We did not detect spatial (no negative correlation between visits to scent stations) or temporal (no difference between times when stations were visited) segregation between coyotes and kit foxes. Visitation to water sources was not different for coyotes between study areas, but kit foxes visited water sources more in Mojave than Great Basin. Our results did not support the indirect effect of water hypothesis in the Great Basin or Mojave Deserts for these two canids. PMID:23844097

Hall, Lucas K; Larsen, Randy T; Knight, Robert N; Bunnell, Kevin D; McMillan, Brock R

2013-01-01

104

Bacteria can mobilize nematode-trapping fungi to kill nematodes  

PubMed Central

In their natural habitat, bacteria are consumed by bacterivorous nematodes; however, they are not simply passive preys. Here we report a defensive mechanism used by certain bacteria to mobilize nematode-trapping fungi to kill nematodes. These bacteria release urea, which triggers a lifestyle switch in the fungus Arthrobotrys oligospora from saprophytic to nematode–predatory form; this predacious form is characterized by formation of specialized cellular structures or ‘traps’. The bacteria significantly promote the elimination of nematodes by A. oligospora. Disruption of genes involved in urea transport and metabolism in A. oligospora abolishes the urea-induced trap formation. Furthermore, the urea metabolite ammonia functions as a signal molecule in the fungus to initiate the lifestyle switch to form trap structures. Our findings highlight the importance of multiple predator–prey interactions in prey defense mechanisms. PMID:25514608

Wang, Xin; Li, Guo-Hong; Zou, Cheng-Gang; Ji, Xing-Lai; Liu, Tong; Zhao, Pei-Ji; Liang, Lian-Ming; Xu, Jian-Ping; An, Zhi-Qiang; Zheng, Xi; Qin, Yue-Ke; Tian, Meng-Qing; Xu, You-Yao; Ma, Yi-Cheng; Yu, Ze-Fen; Huang, Xiao-Wei; Liu, Shu-Qun; Niu, Xue-Mei; Yang, Jin-Kui; Huang, Ying; Zhang, Ke-Qin

2014-01-01

105

Bacteria can mobilize nematode-trapping fungi to kill nematodes.  

PubMed

In their natural habitat, bacteria are consumed by bacterivorous nematodes; however, they are not simply passive preys. Here we report a defensive mechanism used by certain bacteria to mobilize nematode-trapping fungi to kill nematodes. These bacteria release urea, which triggers a lifestyle switch in the fungus Arthrobotrys oligospora from saprophytic to nematode-predatory form; this predacious form is characterized by formation of specialized cellular structures or 'traps'. The bacteria significantly promote the elimination of nematodes by A. oligospora. Disruption of genes involved in urea transport and metabolism in A. oligospora abolishes the urea-induced trap formation. Furthermore, the urea metabolite ammonia functions as a signal molecule in the fungus to initiate the lifestyle switch to form trap structures. Our findings highlight the importance of multiple predator-prey interactions in prey defense mechanisms. PMID:25514608

Wang, Xin; Li, Guo-Hong; Zou, Cheng-Gang; Ji, Xing-Lai; Liu, Tong; Zhao, Pei-Ji; Liang, Lian-Ming; Xu, Jian-Ping; An, Zhi-Qiang; Zheng, Xi; Qin, Yue-Ke; Tian, Meng-Qing; Xu, You-Yao; Ma, Yi-Cheng; Yu, Ze-Fen; Huang, Xiao-Wei; Liu, Shu-Qun; Niu, Xue-Mei; Yang, Jin-Kui; Huang, Ying; Zhang, Ke-Qin

2014-01-01

106

Managing Nematodes without Methyl Bromide  

Technology Transfer Automated Retrieval System (TEKTRAN)

Methyl bromide is an effective pre-plant soil fumigant used to control nematodes in many high-input, high-value production systems including vegetables, nurseries, ornamentals, tree fruits, strawberries, and grapes. Because methyl bromide has provided a reliable return on investment for nematode c...

107

The effects of different plant extracts on nematodes.  

PubMed

The anthelminthic efficacy of some differently obtained extracts of several plants was tested in vivo in laboratory animals and in vitro. The extracts were obtained by ethanolic, methanolic, aqueous, or chloroform, respectively, acetonitrile polyethylenglycol (PEG) and/or propylencarbonate (PC) elution at room temperature or at 37°C. The plants used were bulbs of onions, garlic, chives, coconut, birch tree, ananas, cistrose, banana, chicory, date palm fruit, fig, pumpkin, and neem tree seeds. The worm systems tested both in vivo and in vitro were Trichuris muris and Angiostrongylus cantonensis but only in vivo Toxocara cati. The tests clearly showed that the different extraction methods eluted different components and different mass amounts, which had different efficacies against the above-cited worms. In vitro effects against A. cantonensis and T.muris were best with aqueous extracts, followed by chloroform extracts. The other plant extracts showed only low or no effects on A. cantonensis in vitro. In the case of T. muris, best results were obtained in vivo and in vitro with PEG/PC extracts of the onion followed by the aqueous extract of coconut. The complete elimination of worms in the in vivo experiments with T. muris was obtained when infected mice were treated with a 1:1 mixture of extracts of coconut and onion being produced by elutions with a mixture of 1:1 PEG and PC and fed daily for 8 days. T. cati in a naturally infected cat was eliminated by daily oral application of 6 ml coco's fluid for 5 days. This study shows that a broad spectrum of plants has anti-nematodal activities, the intensity of which, however, depends on the mode of extraction. This implicates that, if results should be really comparable, the same extraction methods at the same temperatures have to be used. Furthermore, efficacy in in vitro systems does not guarantee as good--if at all--efficacy in vivo. PMID:21110041

Klimpel, Sven; Abdel-Ghaffar, Fathy; Al-Rasheid, Khaled A S; Aksu, Gülendem; Fischer, Katja; Strassen, Bianca; Mehlhorn, Heinz

2011-04-01

108

Analysis of Circulating Haemocytes from Biomphalaria glabrata following Angiostrongylus vasorum Infection Using Flow Cytometry  

PubMed Central

Angiostrongylus vasorum is an emerging parasite of dogs and related to carnivores that have an indirect life cycle, with a wide range of terrestrial and aquatic gastropods as the obligatory intermediate host. Unfortunately, the relationship between A. vasorum and their snail hosts remains poorly understood. Circulating haemocytes are the main line of cellular defence involved in the destruction of helminths in snails. Aiming to further characterize the haemocyte subsets in Biomphalaria snails, we have performed a flow cytometric analysis of whole haemolymph cellular components using a multiparametric dual colour labelling procedure. Our findings demonstrated that B. glabrata infected with A. vasorum have two major circulating haemocyte subsets, referred to as small and large haemocytes. Differences in the cell proportion occurred over time. The development of better invertebrate infection control strategies would certainly result in the better control of human diseases caused by other species of the genus Angiostrongylus. Such knowledge will assist in the establishment of novel control strategies aimed at parasites that use molluscs as intermediate hosts and clarify new aspects of the parasite-host relationship regarding cell recognition and activation mechanisms, which are also found in the innate response of vertebrates. PMID:22545202

Barçante, Thales A.; Barçante, Joziana M. P.; Fujiwara, Ricardo T.; Lima, Walter S.

2012-01-01

109

A Serological Survey of Infectious Disease in Yellowstone National Park’s Canid Community  

PubMed Central

Background Gray wolves (Canis lupus) were reintroduced into Yellowstone National Park (YNP) after a >70 year absence, and as part of recovery efforts, the population has been closely monitored. In 1999 and 2005, pup survival was significantly reduced, suggestive of disease outbreaks. Methodology/Principal Findings We analyzed sympatric wolf, coyote (Canis latrans), and red fox (Vulpes vulpes) serologic data from YNP, spanning 1991–2007, to identify long-term patterns of pathogen exposure, identify associated risk factors, and examine evidence for disease-induced mortality among wolves for which there were survival data. We found high, constant exposure to canine parvovirus (wolf seroprevalence: 100%; coyote: 94%), canine adenovirus-1 (wolf pups [0.5–0.9 yr]: 91%, adults [?1 yr]: 96%; coyote juveniles [0.5–1.5 yrs]: 18%, adults [?1.6 yrs]: 83%), and canine herpesvirus (wolf: 87%; coyote juveniles: 23%, young adults [1.6–4.9 yrs]: 51%, old adults [?5 yrs]: 87%) suggesting that these pathogens were enzootic within YNP wolves and coyotes. An average of 50% of wolves exhibited exposure to the protozoan parasite, Neospora caninum, although individuals’ odds of exposure tended to increase with age and was temporally variable. Wolf, coyote, and fox exposure to canine distemper virus (CDV) was temporally variable, with evidence for distinct multi-host outbreaks in 1999 and 2005, and perhaps a smaller, isolated outbreak among wolves in the interior of YNP in 2002. The years of high wolf-pup mortality in 1999 and 2005 in the northern region of the park were correlated with peaks in CDV seroprevalence, suggesting that CDV contributed to the observed mortality. Conclusions/Significance Of the pathogens we examined, none appear to jeopardize the long-term population of canids in YNP. However, CDV appears capable of causing short-term population declines. Additional information on how and where CDV is maintained and the frequency with which future epizootics might be expected might be useful for future management of the Northern Rocky Mountain wolf population. PMID:19756151

Almberg, Emily S.; Mech, L. David; Smith, Douglas W.; Sheldon, Jennifer W.; Crabtree, Robert L.

2009-01-01

110

A serological survey of infectious disease in yellowstone national park's canid community  

USGS Publications Warehouse

Background: Gray wolves (Canis lupus) were reintroduced into Yellowstone National Park (YNP) after a >70 year absence, and as part of recovery efforts, the population has been closely monitored. In 1999 and 2005, pup survival was significantly reduced, suggestive of disease outbreaks. Methodology/Principal Findings: We analyzed sympatric wolf, coyote (Canis latrans), and red fox (Vulpes vulpes) serologic data from YNP, spanning 1991-2007, to identify long-term patterns of pathogen exposure, identify associated risk factors, and examine evidence for disease-induced mortality among wolves for which there were survival data. We found high, constant exposure to canine parvovirus (wolf seroprevalence: 100%; coyote: 94%), canine adenovirus-1 (wolf pups [0.5-0.9 yr]: 91%, adults [???1 yr]: 96%; coyote juveniles [0.5-1.5 yrs]: 18%, adults [???1.6 yrs]: 83%), and canine herpesvirus (wolf: 87%; coyote juveniles: 23%, young adults [1.6-4.9 yrs]: 51%, old adults [???5 yrs]: 87%) suggesting that these pathogens were enzootic within YNP wolves and coyotes. An average of 50% of wolves exhibited exposure to the protozoan parasite, Neospora caninum, although individuals' odds of exposure tended to increase with age and was temporally variable. Wolf, coyote, and fox exposure to canine distemper virus (CDV) was temporally variable, with evidence for distinct multi-host outbreaks in 1999 and 2005, and perhaps a smaller, isolated outbreak among wolves in the interior of YNP in 2002. The years of high wolf-pup mortality in 1999 and 2005 in the northern region of the park were correlated with peaks in CDV seroprevalence, suggesting that CDV contributed to the observed mortality. Conclusions/Significance: Of the pathogens we examined, none appear to jeopardize the long-term population of canids in YNP. However, CDV appears capable of causing short-term population declines. Additional information on how and where CDV is maintained and the frequency with which future epizootics might be expected might be useful for future management of the Northern Rocky Mountain wolf population.

Almberg, E.S.; Mech, L.D.; Smith, D.W.; Sheldon, J.W.; Crabtree, R.L.

2009-01-01

111

Serum concentrations of vitamin D metabolites, vitamins A and E, and carotenoids in six canid and four ursid species at four zoos  

Microsoft Academic Search

Nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. The species analyzed included: African wild dog (Lycaon pictus), arctic fox (Alopex lagopus), gray wolf (Canis lupus), maned wolf (Chrysocyon brachyurus), Mexican wolf (Canis lupus baleiyi), red wolf (Canis rufus), brown bear (Ursus arctos), polar bear (Ursus maritimus), spectacled bear (Tremarctos ornatus), and sun

Susan Crissey; Kimberly Ange; Kerri Slifka; Phyllis Bowen; Maria Stacewicz-Sapuntzakis; Craig Langman; William Sadler; Ann Ward

2001-01-01

112

Eosinophilic meningitis caused by Angiostrongylus cantonensis in an adolescent with mental retardation and pica disorder.  

PubMed

Eosinophilic meningitis or encephalitis is a rare disorder and is most commonly caused by Angiostrongylus cantonensis. Humans are accidentally infected when they ingest raw snails or vegetables contaminated with the parasite larvae. Because of the improvement in sanitary food handling practices, the occurrence of A. cantonensis eosinophilic meningitis has been decreasing in Taiwan in recent decades. The common symptoms and signs of eosinophilic meningitis are severe headache, neck stiffness, paresthesia, vomiting, nausea, and fever. Acute urinary retention is a rare presentation. We report a case of A. cantonensis eosinophilic meningitis in an intellectually disabled patient who presented with acute urinary retention without any other meningeal signs. The patient received supportive treatment with corticosteroid therapy and was discharged and received urinary rehabilitation at home. PMID:23445744

Hsueh, Chang-Wei; Chen, Huan-Sheng; Li, Chen-Hua; Chen, Yu-Wei

2013-02-01

113

Nematode Response to Carbofuran  

PubMed Central

Higher populations of Meloidogyne incognita larvae and Pratylenchus penetrans were recovered from soil treated with carbofuran 10 and 15 days after treatment, respectively, than were recovered from untreated control soil. The number of P. penetrans, however, was lower 50 days after treatment, and symptoms developed only occasionally on the root systems of host plants. Populations of Tylenchorhynchus claytoni inoculated at different distances from the base of corn seedlings growing in carbofuran-treated soil did not move toward the plant, whereas they were attracted in untreated soil from a distance of 12 cm. P. penetrans moved at random in treated agar medium when inoculations occurred 4 cm away from the root tips of tomato seedlings under aseptic conditions. Those nematodes that reached the roots were never observed feeding during a 20-day observation period. Specimens of P. penetrans placed on the developing roots moved at random and never penetrated. In contrast, numerous P. penetrans penetrated roots of seedlings growing in untreated medium. PMID:19319291

Di Sanzo, C. P.

1973-01-01

114

Impact of Conservation Tillage on Nematode Populations  

PubMed Central

Literature reporting the development of conservation tillage and the research that has been conducted on nematode control in crops grown in conservation tillage systems is reviewed. Effects of different types of conservation tillage on population densities of various nematode species in monocropping and multicropping systems, effects of tillage on nematode distribution in the soil profile, effects of conservation tillage on nematode control, and the role of nematology in conservation tillage research are discussed. PMID:19294154

Minton, N. A.

1986-01-01

115

Plant Parasitic Nematodes Associated with Leatherleaf Fern  

PubMed Central

Seven species of plant parasitic nematodes were found to be associated with leatherleaf fern (Rumohra adiantiformis) in central Florida. Of these, Pratylenchus penetrans, Tylenchorhynchus claytoni, and Criconemoides curvatum were commonly encountered. Nematode communities generally included two or three species of plant parasitic nematodes, with greatest diversity in nematode species occurring in ferneries shaded by oak trees. Species diversity was not correlated with fernery age. Leatherleaf fern was tolerant of P. penetrans and T. claytoni in microplot tests. PMID:19294134

Kaplan, D. T.; Osborne, Lance S.

1986-01-01

116

A longitudinal study of Angiostrongylus cantonensis in an urban population of Rattus norvegicus in Brazil: the influences of seasonality and host features on the pattern of infection  

PubMed Central

Background The nematode Angiostrongylus cantonensis is a zoonotic parasite and the most important cause of eosinophilic meningitis worldwide in humans. In Brazil, this disease has been reported in the states of Espírito Santo and Pernambuco. The parasite has been detected in the naturally infected intermediate host, in the states of Rio de Janeiro, Pernambuco and Santa Catarina. The murid Rattus norvegicus R. rattus were recently reported to be naturally infected in Brazil. In this study, we conducted a two-year investigation of the dissemination pattern of A. cantonensis in R. norvegicus in an urban area of Rio de Janeiro state, Brazil, and examined the influence of seasonality, year, host weight and host gender on parasitological parameters of A. cantonensis in rats. Methods The study was conducted in an area of Trindade, São Gonçalo municipality, Rio de Janeiro, Brazil. Prevalence of infected rats, intensity and abundance of A. cantonensis were calculated, and generalized linear models were created and compared to verify the contribution of host gender, host weight, year and seasonality to the variations in A. cantonensis abundance and prevalence in rats. Results The prevalence of A. cantonensis infection was stable during the rainy (71%, CI 58.9- 81.6) and dry seasons (71%, CI 57.9-80.8) and was higher in older rats and in females. Seasonality, host weight (used as a proxy of animal age) and gender were all contributing factors to variation in parasite abundance, with females and heavier (older) animals showing larger abundance of parasites, and extreme values of parasite abundance being more frequent in the dry season. Conclusions The high prevalence of this parasite throughout the study suggests that its transmission is stable and that conditions are adequate for the spread of the parasite to previously unaffected areas. Dispersion of the parasite to new areas may be mediated by males that tend to have larger dispersal ability, while females may be more important for maintaining the parasite on a local scale due to their higher prevalence and abundance of infection. A multidisciplinary approach considering the ecological distribution of the rats and intermediate hosts, as well as environmental features is required to further understand the dynamics of angiostrongyliasis. PMID:24612453

2014-01-01

117

AcCystatin, an immunoregulatory molecule from Angiostrongylus cantonensis, ameliorates the asthmatic response in an aluminium hydroxide/ovalbumin-induced rat model of asthma.  

PubMed

Epidemiological surveys have demonstrated that helminth infections are negatively related to atopic diseases, including asthma. Defining and characterising specific helminth molecules that have excellent immunomodulatory capacities as potential therapeutics for the treatment or prophylaxis of allergic manifestations are of great interest. AcCystatin, a cystatin protease inhibitor of Angiostrongylus cantonensis, is a homologue of other nematode cystatins with immunoregulatory properties. Here, we aim to determine the effects of AcCystatin on an ovalbumin/aluminium hydroxide (OVA/Al[OH]3)-induced rat model of asthma. Wistar rats were randomly divided into four groups, including a control group, an OVA/Al[OH]3-induced asthma group, a group receiving AcCystatin immunisation prior to OVA/Al[OH]3-induced asthma and a group receiving AcCystatin treatment after OVA/Al[OH]3-induced asthma. The numbers of eosinophils, basophils, neutrophils, lymphocytes and monocytes in the peripheral blood and of eosinophils in the bronchoalveolar lavage fluid (BALF) were counted for each animal. The expression levels of the cytokines interferon-?, interleukin (IL) 4, IL-5, IL-6, IL-10, IL17A and tumour necrosis factor receptor-? in BALF, of OVA-specific immunoglobulin E in BALF and serum and of the chemokines eotaxin-1, eotaxin-2, eotaxin-3, MCP-1 and MCP-3 in lung tissue were measured. In addition, the degree of peribronchial and perivascular inflammation and the intensity of goblet cell metaplasia were qualitatively evaluated. The sensitised/challenged rats developed an extensive cell inflammatory response of the airways. AcCystatin administration significantly reduced the cellular infiltrate in the perivascular and peribronchial lung tissues and reduced both goblet mucous production and eosinophil infiltration. The rats that were treated with AcCystatin before or after sensitisation with OVA showed significant decreases in eotaxin-1, eotaxin-3 and MCP-1 expression in the lung tissue. The production of IL-4, IL-5, IL-6 and IL-17A and of OVA-specific IgE antibodies was also significantly reduced in AcCystatin-treated rats compared with untreated asthmatic rats. The AcCystatin treatment was associated with a significant increase in IL-10 levels. Our present findings provide the first demonstration that AcCystatin is an effective agent in the prevention and treatment of the airway inflammation associated with asthma. PMID:25399816

Ji, Pengyu; Hu, Huiling; Yang, Xiangyun; Wei, Xiaoxia; Zhu, Chengcheng; Liu, Jingchao; Feng, Yun; Yang, Fan; Okanurak, Kamolnetr; Li, Na; Zeng, Xin; Zheng, Huanqin; Wu, Zhongdao; Lv, Zhiyue

2015-02-01

118

Nematodes as Biological Control Agents of Insects  

NSDL National Science Digital Library

Entomogenous nematodes are covered here on a short general page that includes several links, one of which is to a PDF with more extensive bio-control with nematodes information. Nine families of nematodes are mentioned which include species that sterilize, alter behavior, or simply kill the insect host.

0000-00-00

119

Plant and Insect Parasitic Nematode Home Page  

NSDL National Science Digital Library

The University of Nebraska at Lincoln provides this site. Created as "an aid for nematode identification and systematic research," the website also serves as an excellent general resource on the science of Nematology. Users will find sections on Nematodes of the Great Plains, an Illustrated Diagnostic Key, Nematode Genera, the Molecular Identification of Nematodes, and others. Resource information at the site includes the Nematology Mailing List (NEMA-L), a Nematode Bibliography Server, the Nematology Employment Bulletin Board, and links to other websites such as the Society of Nematologists.

120

Compatibility of Soil Amendments with Entomopathogenic Nematodes  

PubMed Central

The impact of inorganic and organic fertilizers on the infectivity, reproduction, and population dynamics of entomopathogenic nematodes was investigated. Prolonged (10- to 20-day) laboratory exposure to high inorganic fertilizer concentrations inhibited nematode infectivity and reproduction, whereas short (1-day) exposures increased infectivity. Heterorhabditis bacteriophora was more sensitive to adverse effects than were two species of Steinernema. In field studies, organic manure resulted in increased densities of a native population of Steinernema feltiae, whereas NPK fertilizer suppressed nematode densities regardless of manure applications. Inorganic fertilizers are likely to be compatible with nematodes in tank mixes and should not reduce the effectiveness of nematodes used for short-term control as biological insecticides, but may interfere with attempts to use nematodes as inoculative agents for long-term control. Organic manure used as fertilizer may encourage nematode establishment and recycling. PMID:19274153

Bednarek, Andrzej; Gaugler, Randy

1997-01-01

121

Nonhost Root Penetration by Soybean Cyst Nematode  

PubMed Central

A total of 66 plants in 50 species were inoculated with eggs and juveniles of soybean cyst nematode, Heterodera glycines. Roots were stained and observed for penetration and development of the nematode. Twenty-six plants were not penetrated; twenty-three were penetrated, but there was no development of the nematode; eight were penetrated with some nematode development; two were penetrated and had considerable nematode development, but few nematodes, if any, matured; and seven were penetrated with many nematodes maturing. The penetration of nonhosts may imply some susceptibility and that populations eventually would build up on the penetrated plants. Plants not penetrated may be useful as rotation plants because no reproduction would occur. PMID:19290137

Riggs, R. D.

1987-01-01

122

Plant Nematodes Occurring in Arkansas  

PubMed Central

A total of 110 species of plant nematodes were found in various habitats in Arkansas. Thirty species from 19 genera are reported here for the first time. Included in the new reports are the known plant pathogens Criconemella onoense, Hirshmanniella oryzae, Longidorus elongatus, and Pratylenchus pratensis. PMID:19287671

Wehunt, E. J.; Golden, A. M.; Robbins, R. T.

1989-01-01

123

ORAL NEMATODE INFECTION OF TARANTULAS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Oral nematode infection of Theraphosidae spiders, known as tarantulas, has been recently identified from several collections in the UK and mainland Europe. The disease has also been seen in captive and wild spiders from the Americas, Asia and Africa. Spider symptoms are described from anorexia until...

124

Anthelmintic resistance in equine nematodes.  

PubMed

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 diagnostics that will help define levels of pre-patent infection. This review describes recent advances in each of these areas of research. PMID:25516842

Matthews, Jacqueline B

2014-12-01

125

Complete sequence of the Tibetan Mastiff mitochondrial genome and its phylogenetic relationship with other Canids ( Canis, Canidae).  

PubMed

In this study, the complete sequence of the Tibetan Mastiff mitochondrial genome (mtDNA) was determined, and the phylogenetic relationships between the Tibetan Mastiff and other species of Canidae were analyzed using the coyote (Canis latrans) as an outgroup. The complete nucleotide sequence of the Tibetan Mastiff mtDNA was 16 710 bp, and included 22 tRNA genes, 2S rRNA gene, 13 protein-coding genes and one non-coding region (D-loop region), which is similar to other mammalian mitochondrial genomes. The characteristics of the protein-coding genes, non-coding region, tRNA and rRNA genes among Canidae were analyzed in detail. Neighbor-joining and maximum-parsimony trees of Canids constructed using 12 mitochondrial protein-coding genes showed that as the coyotes and Tibetan wolves clustered together, so too did the gray wolves and domestic dogs, suggesting that the Tibetan Mastiff originated from the gray wolf as did other domestic dogs. Domestic dogs clustered into four clades, implying at least four maternal origins (A to D). The Tibetan Mastiff, which belongs to clade A, appears to be closely related to the Saint Bernard and the Old English Sheepdog. PMID:22440697

Li, Yinxia; Li, Qifa; Zhao, Xingbo; Xie, Zhuang; Xu, Yinxue

2011-01-01

126

Detection of antibodies to Neospora caninum in two species of wild canids, Lycalopex gymnocercus and Cerdocyon thous from Brazil.  

PubMed

Domestic dog (Canis domesticus) and the coyote (Canis latrans) are the only known definitive hosts for the protozoan Neospora caninum that causes abortion in dairy cattle. In the present study, antibodies to N. caninum were sought in three species of wild canids, Cerdocyon thous, Lycalopex gymnocercus and Dusicyon vetulus from Brazil. Antibodies to N. caninum were assayed by the indirect fluorescent antibody test (IFAT) and the Neospora agglutination test (NAT). N. caninum antibodies were found in five of 12 L. gymnocercus with IFAT titers of 1:50 in three, 1:100 in one, and 1:1600 in one, and NAT titers of 1:40, 1:80, 1:160, 1:320, and 1:640 in five animals. Antibodies to N. caninum were found in four of 15 C. thous with IFAT titers of 1:50 in one, and 1:100 in three, and NAT titer of 1:40 in one animal. All 30 D. ventulus were seronegative by IFAT and NAT. PMID:15325054

Cañón-Franco, W A; Yai, L E O; Souza, S L P; Santos, L C; Farias, N A R; Ruas, J; Rossi, F W; Gomes, A A B; Dubey, J P; Gennari, S M

2004-09-01

127

Brazilian Angiostrongylus cantonensis haplotypes, ac8 and ac9, have two different biological and morphological profiles.  

PubMed

Angiostrongylus cantonensis is the etiologic agent of eosinophilic meningoencephalitis in humans. Cases have been recorded in many parts of the world, including Brazil. The aim of this study was to compare the differences in the biology and morphology of two different Brazilian haplotypes of A. : ac8 and ac9. A significantly larger number of L1 larvae eliminated in the faeces of rodents at the beginning of the patent period was observed for ac9 haplotype and compared to the total of L1 larvae eliminated, there was a significant difference between the two haplotypes. The ac9 haplotype showed a significant difference in the proportion of female and male specimens (0.6:1), but the same was not observed for ac8 (1.2:1). The morphometric analysis showed that male and female specimens isolated from ac8 haplotype were significantly larger with respect to body length, oesophagus length, spicule length (male) and distance from the anus to the rear end (female) compared to specimens from ac9. The morphological analysis by light microscopy showed little variation in the level of bifurcations at the lateral rays in the right lobe of the copulatory bursa between the two haplotypes. The biological, morphological and morphometric variations observed between the two haplotypes agree with the observed variation at the molecular level using the cytochrome oxidase subunit I marker and reinforce the possible influence of geographical isolation on the development of these haplotypes. PMID:25591110

Monte, Tainá Cc; Gentile, Rosana; Garcia, Juberlan; Mota, Ester; Santos, Jeannie N; Maldonado Júnior, Arnaldo

2014-12-01

128

First report of a fatal autochthonous canine Angiostrongylus vasorum infection in Belgium.  

PubMed

Canine angiostrongylosis is considered as an emergent disease in Europe and Canada. A fatal case of Angiostrongylus vasorum infection is described in a four and a half month old puppy born in Belgium. The dog was presented with marked neurological disorders, body weight loss, a profound weakness and mild respiratory signs. The dog was given antibiotics and mucolytic compounds with very little improvement and consequently was referred to a specialist for additional examinations. As the general condition of the dog was rapidly declining, the animal was euthanized shortly after on its owners' request and a necropsy was carried out. Extensive gross pulmonary lesions were observed and histopathological examination revealed the presence of numerous larvae with morphology compatible with A. vasorum. Larvae were also found in the product of a bronchoalveolar lavage but fecal material was not examined. The presence of A. vasorum circulating serum antigen was demonstrated through ELISA; additionally an A. vasorum specific PCR was performed on brain material and yielded a positive result. This case confirms that the clinical diagnosis of canine angiostrongylosis can be very challenging especially when respiratory signs are absent or very mild such in the present case. This is the first reported case of canine angiostrongylosis in Belgium. PMID:25449287

Jolly, Sandra; Poncelet, Luc; Lempereur, Laetitia; Caron, Yannick; Bayrou, Calixte; Cassart, Dominique; Grimm, Felix; Losson, Bertrand

2015-02-01

129

Eosinophilic Meningitis Attributable to Angiostrongylus cantonensis Infection in Hawaii: Clinical Characteristics and Potential Exposures  

PubMed Central

The most common infectious cause of eosinophilic meningitis is Angiostrongylus cantonensis, which is transmitted largely by consumption of snails/slugs. We previously identified cases of angiostrongyliasis that occurred in Hawaii from 2001 to 2005; the highest incidence was on the island of Hawaii. We now report symptoms, laboratory parameters, and exposures. Eighteen patients were evaluated; 94% had headache, and 65% had sensory symptoms (paresthesia, hyperesthesia, and/or numbness). These symptoms lasted a median of 17 and 55 days, respectively. Three persons recalled finding a slug in their food/drink. Case-patients on the island of Hawaii were more likely than case-patients on other islands to consume raw homegrown produce in a typical week (89% versus 0%, P < 0.001) and to see snails/slugs on produce (56% versus 0%, P = 0.03). Residents and travelers should be aware of the potential risks of eating uncooked produce in Hawaii, especially if it is from the island of Hawaii and locally grown. PMID:21976573

Hochberg, Natasha S.; Blackburn, Brian G.; Park, Sarah Y.; Sejvar, James J.; Effler, Paul V.; Herwaldt, Barbara L.

2011-01-01

130

77 FR 22185 - Golden Nematode; Removal of Regulated Areas  

Federal Register 2010, 2011, 2012, 2013, 2014

...This section of the FEDERAL REGISTER contains...No. APHIS-2011-0036] Golden Nematode; Removal of Regulated...interim rule that amended the golden nematode regulations by removing...these two townships are free of golden nematode, and we...

2012-04-13

131

Molecular phylogeny of beetle associated diplogastrid nematodes suggests host switching rather than nematode-beetle coevolution  

Microsoft Academic Search

BACKGROUND: Nematodes are putatively the most species-rich animal phylum. They have various life styles and occur in a variety of habitats, ranging from free-living nematodes in aquatic or terrestrial environments to parasites of animals and plants. The rhabditid nematode Caenorhabditis elegans is one of the most important model organisms in modern biology. Pristionchus pacificus of the family of the Diplogastridae

Werner E Mayer; Matthias Herrmann; Ralf J Sommer

2009-01-01

132

Protein variation in cyst nematodes  

Microsoft Academic Search

The magnitude of the protein divergence strongly suggests that Globodera<\\/u>rostochiensis<\\/u> and G.<\\/u>pallida<\\/u> have experienced hardly any morphological evolution during a time period of millions of years (chapter II). These morphologically nearly indistinguishable potato cyst nematode species are discriminated from one another by 70 % of their proteins revealed by two dimensional gel electrophoresis (2-DGE), which definitively excludes a recent divergence

J. Bakker

1987-01-01

133

Management of the Citrus Nematode, Tylenchulus semipenetrans.  

PubMed

Of the many nematode species that parasitize citrus, Tylenchulus semipenetrans is the most important on a worldwide basis. Management of the citrus nematode remains problematic as no one tactic gives adequate control of the nematode. An overall management strategy must include such components as site selection, use of non-infected nursery stock, use of at lease one post-plant nematode control tactic, and careful management of other elements of the environment that may stress the trees. Nematicides continue to play a key role in management of this pest. Optimum results require careful attention to application techniques. PMID:19262822

Verdejo-Lucas, S; McKenry, M V

2004-12-01

134

Management of the Citrus Nematode, Tylenchulus semipenetrans  

PubMed Central

Of the many nematode species that parasitize citrus, Tylenchulus semipenetrans is the most important on a worldwide basis. Management of the citrus nematode remains problematic as no one tactic gives adequate control of the nematode. An overall management strategy must include such components as site selection, use of non-infected nursery stock, use of at lease one post-plant nematode control tactic, and careful management of other elements of the environment that may stress the trees. Nematicides continue to play a key role in management of this pest. Optimum results require careful attention to application techniques. PMID:19262822

Verdejo-Lucas, S.; McKenry, M. V.

2004-01-01

135

Improved molecular detection of Angiostrongylus cantonensis in mollusks and other environmental samples with a species-specific ITS1-based TaqMan assay  

Technology Transfer Automated Retrieval System (TEKTRAN)

Angiostrongylus cantonensis is the most common cause of human eosinophilic meningitis. Humans can become infected by ingesting food items contaminated with the third-stage infectious larvae released from infected mollusks as well as by ingesting mollusks or paratenic hosts carrying the infectious st...

136

Calibration of estimated biting forces in domestic canids: comparison of post-mortem and in vivo measurements  

PubMed Central

Estimates of biting forces are widely used in paleontological and comparative studies of feeding mechanics and performance, and are usually derived from lever models based on measurements made on the skull that are relevant to the mechanics of the masticatory system. Owing to assumptions and unmeasurable errors in their estimation, such values are used comparatively rather than as absolute estimates. The purpose of this paper was to provide calibration of post-mortem calculated bite force estimates by comparing them to in vivo forces derived from a sample of 20 domestic dogs (Canis familiaris) during muscle stimulation under general anaesthesia. Two lever models previously described in the literature were used to estimate post-mortem values, and regression analysis was also performed to derive best-fit equations against a number of morphometric measurements on the skull. The ranges of observed forces in vivo were 147–946 N at the canine, and 524–3417 N at the second molar. The lever models substantially underestimated these forces, giving mean values between 39% and 61% of the observed means. Predictability was considerably improved by removing the linear bias and deviation of the regression slope from unity with an adjustment equation. Best-fit statistical models developed on these animals performed considerably better (calculated means within 0.54% of observed means) and included easily measureable variables such as bodyweight, dimensions of the temporalis fossa and out-lever from the jaw joint to the biting tooth. These data should lead to more accurate absolute, rather than relative, estimates of biting forces for other extant and fossil canids, and other carnivorans by extrapolation. PMID:18510505

Ellis, Jennifer Lynn; Thomason, Jeffrey J; Kebreab, Ermias; France, James

2008-01-01

137

Radiographic analysis of vocal tract length and its relation to overall body size in two canid species  

PubMed Central

Body size is an important determinant of resource and mate competition in many species. Competition is often mediated by conspicuous vocal displays, which may help to intimidate rivals and attract mates by providing honest cues to signaler size. Fitch proposed that vocal tract resonances (or formants) should provide particularly good, or honest, acoustic cues to signaler size because they are determined by the length of the vocal tract, which in turn, is hypothesized to scale reliably with overall body size. There is some empirical support for this hypothesis, but to date, many of the effects have been either mixed for males compared with females, weaker than expected in one or the other sex, or complicated by sampling issues. In this paper, we undertake a direct test of Fitch’s hypothesis in two canid species using large samples that control for age- and sex-related variation. The samples involved radiographic images of 120 Portuguese water dogs Canis lupus familiaris and 121 Russian silver foxes Vulpes vulpes. Direct measurements were made of vocal tract length from X-ray images and compared against independent measures of body size. In adults of both species, and within both sexes, overall vocal tract length was strongly and significantly correlated with body size. Effects were strongest for the oral component of the vocal tract. By contrast, the length of the pharyngeal component was not as consistently related to body size. These outcomes are some of the clearest evidence to date in support of Fitch’s hypothesis. At the same time, they highlight the potential for elements of both honest and deceptive body signaling to occur simultaneously via differential acoustic cues provided by the oral versus pharyngeal components of the vocal tract. PMID:24363497

Plotsky, K.; Rendall, D.; Riede, T.; Chase, K.

2013-01-01

138

Molecular assessment of hepatozoon (Apicomplexa: adeleorina) infections in wild canids and rodents from north Africa, with implications for transmission dynamics across taxonomic groups.  

PubMed

Parasites play a major role in ecosystems, and understanding of host-parasite interactions is important for predicting parasite transmission dynamics and epidemiology. However, there is still a lack of knowledge about the distribution, diversity, and impact of parasites in wildlife, especially from remote areas. Hepatozoon is a genus of apicomplexan parasites that is transmitted by ingestion of infected arthropod vectors. However, alternative modes of transmission have been identified such as trophic transmission. Using the 18S rRNA gene as a marker, we provide an assessment of Hepatozoon prevalence in six wild canid and two rodent species collected between 2003 and 2012 from remote areas in North Africa. By combining this with other predator-prey systems in a phylogenetic framework, we investigate Hepatozoon transmission dynamics in distinct host taxa. Prevalence was high overall among host species (African jerboa Jaculus jaculus [17/47, 36%], greater Egyptian jerboa Jaculus orientalis [5/7, 71%], side-striped jackal Canis adustus [1/2, 50%], golden jackal Canis aureus [6/32, 18%], pale fox Vulpes pallida [14/28, 50%], Rüppell's fox Vulpes rueppellii [6/11, 55%], red fox Vulpes vulpes [8/16, 50%], and fennec fox Vulpes zerda [7/11, 42%]). Phylogenetic analysis showed further evidence of occasional transmission of Hepatozoon lineages from prey to canid predators, which seems to occur less frequently than in other predator-prey systems such as between snakes and lizards. Due to the complex nature of the Hepatozoon lifecycle (heteroxenous and vector-borne), future studies on these wild host species need to clarify the dynamics of alternative modes of Hepatozoon transmission and identify reservoir and definitive hosts in natural populations. We also detected putative Babesia spp. (Apicomplexa: Piroplasmida) infections in two canid species from this region, V. pallida (1/28) and V. zerda (1/11). PMID:25050803

Maia, João P; Alvares, Francisco; Boraty?ski, Zbyszek; Brito, José C; Leite, João V; Harris, D James

2014-10-01

139

Global Decline in Suitable Habitat for Angiostrongylus (?=?Parastrongylus) cantonensis: The Role of Climate Change  

PubMed Central

Climate change is implicated in the alteration of the ranges of species worldwide. Such shifts in species distributions may introduce parasites/pathogens, hosts, and vectors associated with disease to new areas. The parasite Angiostrongylus (?=?Parastrongylus) cantonensis is an invasive species that causes eosinophilic meningitis in humans and neurological abnormalities in domestic/wild animals. Although native to southeastern Asia, A. cantonensis has now been reported from more than 30 countries worldwide. Given the health risks, it is important to describe areas with potentially favorable climate for the establishment of A. cantonensis, as well as areas where this pathogen might become established in the future. We used the program Maxent to develop an ecological niche model for A. cantonensis based on 86 localities obtained from published literature. We then modeled areas of potential A. cantonensis distribution as well as areas projected to have suitable climatic conditions under four Representative Concentration Pathways (RCP) scenarios by the 2050s and the 2070s. The best model contained three bioclimatic variables: mean diurnal temperature range, minimum temperature of coldest month and precipitation of warmest quarter. Potentially suitable habitat for A. cantonensis was located worldwide in tropical and subtropical regions. Under all climate change RCP scenarios, the center of the projected distribution shifted away from the equator at a rate of 68–152 km per decade. However, the extent of areas with highly suitable habitat (>50%) declined by 10.66–15.66% by the 2050s and 13.11–16.11% by the 2070s. These results conflict with previous studies, which have generally found that the prevalence of tropical pathogens will increase during the 21st century. Moreover, it is likely that A. cantonensis will continue to expand its current range in the near future due to introductions and host expansion, whereas climate change will reduce the total geographic area of most suitable climatic conditions during the coming decades. PMID:25122457

York, Emily M.; Butler, Christopher J.; Lord, Wayne D.

2014-01-01

140

Gastrointestinal nematodes, trace elements, and immunity  

Microsoft Academic Search

1 The exploration of the scientific literature on the interrelationship among trace ele- ments, gastrointestinal nematodes, and their requisite Th2 immunity demonstrates extensive literature but regrettably, research remains inadequate and sparse, with far fewer studies having investigated the interrelationship among trace elements and host immunity in infected hosts. Gastrointestinal nematodes, such as hookworms, Ascaris lumbricoides, and Trichuris trichiura, require activation

Kristine G. Koski; Marilyn E. Scott

2003-01-01

141

Managing nematode pests in Midsouth soybeans  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean producers must contend with nematode pests, several species of which may inhabit a single field. Significant yield losses caused by soybean cyst (Heterodera glycines), southern root-knot (Meloidogyne incognita), reniform (Rotylenchulus reniformis) and other nematodes were estimated at 2.6% (...

142

Influence of symbiotic bacteria on entomopathogenic nematode--host interactions  

Technology Transfer Automated Retrieval System (TEKTRAN)

There are three players in the infection process of entomopathogenic nematodes (Steinernematidae and Heterorhabditidae): the nematodes themselves, the host insect, and the nematode’s mutualistic bacteria (Xenorhabdus and Photorhabdus spp.). As a host infection progresses, all three of these players...

143

Genetic analysis of root-knot nematode resistance in potato  

Microsoft Academic Search

The development of potato varieties with resistance towards the potato cyst nematode, allowed a dramatic decrease of the use of nematicides. Subsequently the population of the free living nematodes and the root-knot nematodes ( Meloidogyne spp.) has increased. Among the root-knot nematodes, three Meloidogyne species are important in the potato cultivation in The Netherlands: M. hapla , M. chitwoodi and

J. Draaistra

2006-01-01

144

Free-living and Plant-Parasitic Nematodes (Roundworms)  

NSDL National Science Digital Library

This lesson introduces learners to the world of nematodes (roundworms). Learners construct Baermann funnels to extract nematodes from soil and learn to differentiate stylet-bearing nematodes (most likely plant parasites) from free-living nematodes. This lesson includes background information, study questions with answers for learners, and diagrams. Dissecting and compound microscopes are required (not included in cost of materials).

Gregory L. Tylka

2011-01-01

145

Crab-eating fox (Cerdocyon thous), a South American canid, as a definitive host for Hammondia heydorni.  

PubMed

Hammondia heydorni is a cyst forming coccidia closely related to other apicomplexans, such as Toxoplasma gondii, Neospora caninum and Hammondia hammondi with a two-host life cycle. Dogs and other canids as red foxes (Vulpes vulpes) and coyotes (Canis latrans) may serve as definitive hosts for H. heydorni. Sporulated oocysts are infective for cattle, sheep and goats, which may serve as intermediate hosts. Herein, we describe the ability of crab-eating fox (Cerdocyon thous), a wild carnivore that is commonly found from northern Argentina to northern South America, to serve as definitive host of H. heydorni. The whole masseter muscle and brain from two 2-year-old bovines were collected, minced and pooled together for the fox infection. The bovine pooled tissues were equally administered to four foxes, in two consecutive days. Two foxes shed subspherical unsporulated oocysts measuring 10-15microm, after 8 and 9 days post-infection, respectively. One of the foxes eliminated oocysts for 5 days, while the other fox shed oocysts for 9 days. A DNA sample of oocysts detected at each day of oocyst elimination was tested by two PCRs, one of them carried out employing primers directed to the common toxoplasmatiid 18S and 5.8S ribosomal RNA coding genes (PCR-ITS1) and the other based on heat-shock protein 70kDa coding gene (PCR-HSP70). These samples were also submitted to a N. caninum specific nested-PCR protocol based on a N. caninum specific gene (Nc5-nPCR). All of them were positive by PCR-ITS1 and PCR-HSP70 but negative by Nc5-nPCR. The PCR-ITS1 and PCR-HSP70 nucleotide sequences amplified from the oocysts shed by the foxes revealed 100% identity with homologous sequences of H. heydorni. In conclusion, it is clear that H. heydorni also uses the crab-eating fox as a definitive host. The crab-eating fox is usually reported to live in close contact with livestock in several regions of Brazil. Therefore, it is reasonable to infer that such carnivores may play an important role in the sylvatic and domestic cycles of H. heydorni infection. PMID:19303215

Soares, Rodrigo M; Cortez, Luiz R P B; Gennari, Solange M; Sercundes, Michelle K; Keid, Lara B; Pena, Hilda F J

2009-05-26

146

Laser capture microdissection of nematode feeding cells.  

PubMed

Obligate plant-parasitic nematodes, such as cyst nematodes (Heterodera and Globodera spp.) and root-knot nematodes (Meloidogyne spp.), form specialized feeding cells in host plant roots. These feeding cells provide the sole source of nutrition for the growth and reproduction of the nematode to complete its life cycle. Feeding cell formation involves complex physiological and morphological changes to normal root cells and is accompanied by dramatic changes in plant gene expression. The distinct features of feeding cells suggest that their formation entails a unique gene expression profile, a better understanding of which will assist in building models to explain signaling pathways that modulate transcriptional changes in response to nematodes. Ultimately, this knowledge can be used to design strategies to develop resistance against nematodes in crop plants. Feeding cells comprise a small fraction of the total root cell population, and identification of plant gene expression changes specific to these cells is difficult. Until recently, the specific isolation of nematode feeding cells could be accomplished only by manual dissection or microaspiration. These approaches are limited in that only mature feeding cells can be isolated. These limitations in tissue accessibility for macromolecule isolation at different stages of feeding cell development can be overcome through the use of laser microdissection (LM), a technique that enables the specific isolation of feeding cells from early to late stages for RNA isolation, amplification, and downstream analysis. PMID:21359812

Ithal, Nagabhushana; Mitchum, Melissa G

2011-01-01

147

Ascaroside Signaling is Widely Conserved Among Nematodes  

PubMed Central

Summary Background Nematodes are among the most successful animals on earth and include important human pathogens, yet little is known about nematode pheromone systems. A group of small molecules called ascarosides has been found to mediate mate finding, aggregation, and developmental diapause in Caenorhabditis elegans, but it is unknown whether ascaroside signaling exists outside of the genus Caenorhabditis. Results To determine whether ascarosides are used as signaling molecules by other nematode species, we performed a mass spectrometry-based screen for ascarosides in secretions from a variety of both free-living and parasitic (plant, insect, and animal) nematodes. We found that most of the species analyzed, including nematodes from several different clades, produce species-specific ascaroside mixtures. In some cases, ascaroside biosynthesis patterns appear to correlate with phylogeny, whereas in other cases, biosynthesis seems to correlate with lifestyle and ecological niche. We further show that ascarosides mediate distinct nematode behaviors, such as retention, avoidance, and long-range attraction, and that different nematode species respond to distinct, but overlapping, sets of ascarosides. Conclusions Our findings indicate that nematodes utilize a conserved family of signaling molecules despite having evolved to occupy diverse ecologies. Their structural features and level of conservation are evocative of bacterial quorum sensing, where acyl homoserine lactones (AHLs) are both produced and sensed by many species of Gram-negative bacteria. The identification of species-specific ascaroside profiles may enable pheromone-based approaches to interfere with reproduction and survival of parasitic nematodes, which are responsible for significant agricultural losses and many human diseases worldwide. PMID:22503501

Choe, Andrea; von Reuss, Stephan H.; Kogan, Dima; Gasser, Robin B.; Platzer, Edward G.; Schroeder, Frank C.; Sternberg, Paul W.

2012-01-01

148

Biocontrol: Fungal Parasites of Female Cyst Nematodes  

PubMed Central

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 Woll., to nondamaging levels. The potential of these nematophagous fungi as biocontrol agents is discussed. PMID:19300700

Kerry, Brian

1980-01-01

149

Visualizing Bacteria in Nematodes using Fluorescent Microscopy  

PubMed Central

Symbioses, the living together of two or more organisms, are widespread throughout all kingdoms of life. As two of the most ubiquitous organisms on earth, nematodes and bacteria form a wide array of symbiotic associations that range from beneficial to pathogenic 1-3. One such association is the mutually beneficial relationship between Xenorhabdus bacteria and Steinernema nematodes, which has emerged as a model system of symbiosis 4. Steinernema nematodes are entomopathogenic, using their bacterial symbiont to kill insects 5. For transmission between insect hosts, the bacteria colonize the intestine of the nematode's infective juvenile stage 6-8. Recently, several other nematode species have been shown to utilize bacteria to kill insects 9-13, and investigations have begun examining the interactions between the nematodes and bacteria in these systems 9. We describe a method for visualization of a bacterial symbiont within or on a nematode host, taking advantage of the optical transparency of nematodes when viewed by microscopy. The bacteria are engineered to express a fluorescent protein, allowing their visualization by fluorescence microscopy. Many plasmids are available that carry genes encoding proteins that fluoresce at different wavelengths (i.e. green or red), and conjugation of plasmids from a donor Escherichia coli strain into a recipient bacterial symbiont is successful for a broad range of bacteria. The methods described were developed to investigate the association between Steinernema carpocapsae and Xenorhabdus nematophila14. Similar methods have been used to investigate other nematode-bacterium associations 9,15-18and the approach therefore is generally applicable. The method allows characterization of bacterial presence and localization within nematodes at different stages of development, providing insights into the nature of the association and the process of colonization 14,16,19. Microscopic analysis reveals both colonization frequency within a population and localization of bacteria to host tissues 14,16,19-21. This is an advantage over other methods of monitoring bacteria within nematode populations, such as sonication 22or grinding 23, which can provide average levels of colonization, but may not, for example, discriminate populations with a high frequency of low symbiont loads from populations with a low frequency of high symbiont loads. Discriminating the frequency and load of colonizing bacteria can be especially important when screening or characterizing bacterial mutants for colonization phenotypes 21,24. Indeed, fluorescence microscopy has been used in high throughput screening of bacterial mutants for defects in colonization 17,18, and is less laborious than other methods, including sonication 22,25-27and individual nematode dissection 28,29. PMID:23117838

Murfin, Kristen E.; Chaston, John; Goodrich-Blair, Heidi

2012-01-01

150

Acute neurological signs as the predominant clinical manifestation in four dogs with Angiostrongylus vasorum infections in Denmark  

PubMed Central

Four dogs with acute neurological signs caused by haemorrhages in the central nervous system were diagnosed with Angiostrongylus vasorum infection as the underlying aetiology. Two dogs presented with brain lesions, one dog with spinal cord lesions and one with lesions in both the brain and spinal cord. Only one dog presented with concurrent signs of classical pulmonary angiostrongylosis (respiratory distress, cough), and only two dogs displayed overt clinical signs of haemorrhages. Results of coagulation assays were inconsistent. Neurological signs reflected the site of pathology and included seizures, various cranial nerve deficits, vestibular signs, proprioceptive deficits, ataxia and paraplegia. One dog died and three were euthanised due to lack of improvement despite medical treatment. This emphasises canine angiostrongylosis as a potential cause of fatal lesions of the central nervous system and the importance of including A. vasorum as a differential diagnosis in young dogs with acute neurological signs in Denmark. PMID:21711538

2011-01-01

151

The occurrence of Angiostrongylus vasorum in terrestrial slugs from forests and parks in the Copenhagen area, Denmark.  

PubMed

A total of 298 slugs belonging to four species, Arion lusitanicus, A. ater, A. ater rufus and Limax maximus, were collected from six different localities within a radius of 30 km from Copenhagen and examined for naturally acquired Angiostrongylus vasorum infection. Overall, 28 slugs (9%) were infected, but the prevalence varied among the studied localities: Rude Forest (26%), West Amager Forest (18%), Jaegersborg Forest and Deer Park (8%), Frederiksberg Park (4%), Assistens Cemetery Park (0%) and Frederiksberg Botanical Garden (0%). Only third-stage larvae (L3) were recovered from the slugs, in numbers ranging from 1 to 392 per slug. Overall 82% of the infected slugs harboured fewer than 10 larvae and only 14% harboured over 100 larvae. PMID:19460193

Ferdushy, T; Kapel, C M O; Webster, P; Al-Sabi, M N S; Grønvold, J

2009-12-01

152

Endemic infections of Parastrongylus (=Angiostrongylus) costaricensis in two species of nonhuman primates, raccoons, and an opossum from Miami, Florida.  

PubMed

Parastrongylus (=Angiostrongylus) costaricensis was first reported in the United States from cotton rats, Sigmodon hispidus, in Texas in 1979. Here, we report the findings of P. costaricensis in a siamang (Hylobates syndactylus) from the Miami MetroZoo, in 2 Ma's night monkeys (Aotus nancymaae) from the DuMond Conservancy located at Monkey Jungle in Miami, in 4 raccoons (Procyon lotor) trapped near the MetroZoo, and in an opossum (Didelphis virginiana) trapped at the MetroZoo. These records are the first records of P. costaricensis from all 4 species of hosts. All of the primates were zoo-born, and the raccoons and opossum were native, indicating that this parasite is now endemic at these 2 sites. PMID:16729706

Miller, Christine L; Kinsella, John M; Garner, Michael M; Evans, Sian; Gullett, Patricia A; Schmidt, Robert E

2006-04-01

153

Effect of Thai ‘koi-hoi’ food flavoring on the viability and infectivity of the third-stage larvae of Angiostrongylus cantonensis (Nematoda: Angiostrongylidae)  

Microsoft Academic Search

The effect of the food flavoring of ‘koi-hoi’, a popular Thai snail dish, on the viability and infectivity of Angiostrongylus (=Parastrongylus) cantonensis third-stage larvae was assessed in a mouse model. Groups of 50 each of actively moving, non-motile coiled, and extended larvae were obtained from experimentally infected snail meat, after one-hour exposure to standard ‘koi-hoi’ flavoring. These larvae and groups

Praphathip Eamsobhana; Adisak Yoolek; Hoi-Sen Yong

2010-01-01

154

Biocontrol: Fungi as Nematode Control Agents  

PubMed Central

The fungal antagonists of nematodes consist of a great variety of organisms belonging to widely divergent orders and families of fungi. They include the nematode-trapping fungi, endoparasitic fungi, parasites of nematode eggs and cysts, and fungi which produce metabolites toxic to nematodes. The diversity, adaptations, and distribution of nematode-destroying fungi and taxonomic problems encountered in their study are reviewed. The importance of nemato-phagous fungi in soil biology, with special emphasis on their relationship to populations of plant-parasitic nematodes, is considered. While predacious fungi have long been investigated as possible biocontrol agents and have often exhibited spectacular results in vitro, their performance in field studies has generated little enthusiasm among nematologists. To date no species has demonstrated control of any plant pest to a degree achieved with nematicides, but recent studies have provided a much clearer concept of possibilities and problems in the applied use of fungal antagonists. The discovery of new species, which appear to control certain pests effectively under specific conditions, holds out some promise that fungi may be utilized as alternatives to chemical control after a more thorough and expanded study of their biology and ecology. PMID:19300699

Mankau, R.

1980-01-01

155

Phenanthrene Bioaccumulation in the Nematode Caenorhabditis elegans.  

PubMed

The contribution of food to the bioaccumulation of xenobiotics and hence toxicity is still an ambiguous issue. It is becoming more and more evident that universal statements cannot be made, but that the relative contribution of food-associated xenobiotics in bioaccumulation depends on species, substance, and environmental conditions. Yet, small-sized benthic or soil animals such as nematodes have largely been disregarded so far. Bioaccumulation of the polycyclic aromatic hydrocarbon phenanthrene in the absence and presence of bacterial food was measured in the nematode Caenorhabditis elegans. Elimination of phenanthrene in the nematodes was biphasic, suggesting that there was a slowly exchanging pool within the nematodes or that biotransformation of phenanthrene took place. Even with food present, dissolved phenanthrene was still the major contributor to bioaccumulated compound in nematode tissues, whereas the diet only contributed about 9%. Toxicokinetic parameters in the treatment without food were different from the ones of the treatment with bacteria, possibly because nematodes depleted their lipid reserves during starvation. PMID:25607770

Spann, Nicole; Goedkoop, Willem; Traunspurger, Walter

2015-02-01

156

The occurrence of the rat lungworm, Angiostrongylus cantonensis, in nonindigenous snails in the Gulf of Mexico region of the United States  

USGS Publications Warehouse

Nonindigenous apple snails, Pomacea maculata (formerly Pomacea insularum), are currently spreading rapidly through the southeastern United States. This mollusk serves as an intermediate host of the rat lungworm parasite (Angiostrongylus cantonensis), which can cause eosinophilic meningitis in humans who consume infected mollusks. A PCR-based detection assay was used to test nonindigenous apple snails for the rat lungworm parasite in Louisiana, Texas, Mississippi, and Florida. Only apple snails obtained from the New Orleans, Louisiana, area tested positive for the parasite. These results provide the first evidence that Angiostrongylus cantonensis does occur in nonindigenous apple snails in the southeastern United States. Additionally, Angiostrongylus cantonensis was identified in the terrestrial species Achatina fulica in Miami, Florida, indicating that rat lungworm is now established in Florida as well as Louisiana. Although the study suggests that the rat lungworm is not widespread in the Gulf States region, the infected snail population could still pose a risk to human health and facilitate the spread of the parasite to new areas.

Teem, John L.; Qvarnstrom, Yvonne; Bishop, Henry S.; da Silva, Alexandre J.; Carter, Jacoby; White-McLean, Jodi; Smith, Trevor

2013-01-01

157

Influence of metalaxyl on three nematodes of citrus.  

PubMed

Metalaxyl significantly reduced population of Pratylenchus coffeae, Radopholus similis, and Tylenchulus semipenetrans in roots of Citrus limon (rough lemon) under greenhouse conditions. Postinoculation treatment of rough lemon seedlings was not as effective i n reducing nematode populations as was treatment before inoculation. Fewer nematodes infected metalaxyl-treated roots than nontreated roots. However, incubation of nematodes in metalaxyl did not inhibit nematode motility or their ability to locate and infect roots. Cellular responses to nematode injection differed between treated and nontreated tissues. Metalaxyl appeared to confer nematode contraol by modifying citrus roots such that a normally susceptible rootstock became tolerant. PMID:19295833

Kaplan, D T

1983-07-01

158

Cytogenetic studies and karyotype nomenclature of three wild canid species: maned wolf (Chrysocyon brachyurus), bat-eared fox (Otocyon megalotis) and fennec fox (Fennecus zerda).  

PubMed

We have analysed the chromosomes of three wild and endangered canid species: the maned wolf (Chrysocyon brachyurus), the bat-eared fox (Otocyon megalotis) and the fennec fox (Fennecuszerda) using classical and molecular cytogenetic methods. For the first time detailed and encompassing descriptions of the chromosomes are presented including the chromosomal assignment of nucleolar organizer regions and the 5S rRNA gene cluster. We propose a karyotype nomenclature with ideograms including more than 300 bands per haploid set for each of these three species which will form the basis for further research. In addition, we propose four basic different patterns of karyotype organization in the family Canidae. A comparison of these patterns with the most recent molecular phylogeny of Canidae revealed that the karyotype evolution of a species is not always strongly connected with its phylogenetic position. Our findings underline the need and justification for basic cytogenetic work in rare and exotic species. PMID:18544923

Pie?kowska-Schelling, A; Schelling, C; Zawada, M; Yang, F; Bugno, M; Ferguson-Smith, M

2008-01-01

159

Wang et al.: Mites and Nematodes Associated with Termites 499 MITES AND NEMATODES ASSOCIATED WITH THREE  

E-print Network

Wang et al.: Mites and Nematodes Associated with Termites 499 MITES AND NEMATODES ASSOCIATED WITH THREE SUBTERRANEAN TERMITE SPECIES (ISOPTERA: RHINOTERMITIDAE) CHANGLU WANG1,3 , JANINE E. POWELL1,4 AND BARRY M. O'CONNOR2 1 Formosan Subterranean Termite Research Unit, USDA-ARS, Stoneville, MS 38776 2

Wang, Changlu

160

Microbial Ecology and Nematode Control in Natural Ecosystems  

Microsoft Academic Search

\\u000a Plant-parasitic nematodes have traditionally been studied in agricultural systems, where they can be pests of importance on\\u000a a wide range of crops. Nevertheless, nematode ecology in natural ecosystems is receiving increasing interest because of the\\u000a role of nematodes in soil food webs, nutrient cycling, influences on vegetation composition, and because of their indicator\\u000a value. In natural ecosystems, plant-parasitic nematode populations

Sofia R. Costa; Wim H. van der Putten; Brian R. Kerry

2011-01-01

161

Nature and Inheritance of Nematode Resistance in Cereals  

PubMed Central

Resistance to a number of nematodes is present in varieties of temperate and tropical cereals. The occurrence, nature, and inheritance of varietal resistance in cereals is reviewed. Evaluation of the practical significance of nematode resistance in a particular host-nematode combination is discussed in relation to host efficiency, host sensitivity, genetic control of resistance, and presence of virulence in the nematode population. PMID:19308117

Cook, R.

1974-01-01

162

Biological Control Potential of Neoaplectanid Nematodes  

PubMed Central

The neoaplectanids are among the most studied of all entomogenous nematodes. Because these nematodes kill their insect hosts, they are regarded as having excellent potential as biological control agents. While the host specificity of most entontogenous nematodes tends to limit their potential usefulness, the broad host range and high virulence of neoaplectanids make them attractive candidates for industrial development. Also, recent development of economical mass rearing procedures appears to make production on a commercial basis feasible. Infective stages may be stored for years trader various laboratory conditions. Although entomogenous nematodes, as parasites, are exempt from govermnent registration requirements, the mutualistic association of neoaplectanid nematodes with a bacterium will likely necessitate a detailed safety evaluation. Studies conducted to date indicate a lack of pathogenicity to mammals. Field trial success has been limited by the intolerance of infective stages to mffavorable environmental conditions, particularly low moisture. Applications against pests on exposed plant foliage have been especially disappointing. More encouraging anti consistent results have been obtained in more favorable environments, including soil and aquatic habitats, but the most promising treatment sites ntay be cryptic habitats where infective stages are shehered from environmental extremes. Cryptic habitats also exploit the ability of neoaplectanids to actively seek out hosts in recessed places where conventional insecticide applications are intpractical. PMID:19300757

Gaugler, Randy

1981-01-01

163

Nematodes associated with blackberry in arkansas.  

PubMed

A survey of the nematodes in blackberry (Rubus sp.) rhizospheres was conducted in Arkansas from 1986 to 1989. The state was divided arbitrarily into four quadrants. A total of 134 soil samples was collected, and 150-cm 3 subsamples were assayed for nematodes. Twenty-one species of plant-parasitic nematodes in 11 genera were extracted from the samples. There were differences (P = 0.05) among quadrants of the state in percentage occurrence of the nematodes and in population densities in samples. Xiphinema americanum, Helicotylenchus spp. (H. paraplatyurus, H. platyurus, and H. pseudorobustus), and Pratylenchus spp. (P. vulnus and P. zeae) were found in all quadrants. Xiphinema americanum population density was near 1,000 per 150 cm(3) soil in soil samples from two locations. Other nematodes found in one or more quadrants were Criconemella spp. (C. axeste, C. curvata, C. denoudeni, C. ornata, C. sphaerocephala, and C. xenoplax), Paratrichodorus minor, Tylenchorhynchus claytoni, Hirschmanniella oryzae, Hoplolaimus magnistylus, Scutellonema bradys, and undescribed species of Criconema, Tylenchulus, Xiphinema, and Meloidogyne. Criconemella sphaerocephala and Helicotylenchus platyurus are reported from Arkansas for the first time. Helicotylenchus paraplatyurus is reported from the United States for the first time. PMID:19283173

Wehunt, E J; Golden, A M; Clark, J R; Kirkpatrick, T L; Baker, E C; Brown, M A

1991-10-01

164

Molecular Transfer of Nematode Resistance Genes  

PubMed Central

Recombinant DNA techniques have been used to introduce agronomically valuable traits, including resistance to viruses, herbicides, and insects, into crop plants. Introduction of these genes into plants frequently involves Agrobacterium-mediated gene transfer. The potential exists for applying this technology to nematode control by introducing genes conferring resistance to nematodes. Transferred genes could include those encoding products detrimental to nematode development or reproduction as well as cloned host resistance genes. Host genes that confer resistance to cyst or root-knot nematode species have been identified in many plants. The best characterized is Mi, a gene that confers resistance to root-knot nematodes in tomato. A map-based cloning approach is being used to isolate the gene. For development of a detailed map of the region of the genome surrounding Mi, DNA markers genetically linked to Mi have been identified and analyzed in tomato lines that have undergone a recombination event near Mi. The molecular map will be used to identify DNA corresponding to Mi. We estimate that a clone of Mi will be obtained in 2-5 years. An exciting prospect is that introduction of this gene will confer resistance in plant species without currently available sources of resistance. PMID:19282989

Williamson, V. M.; Ho, J.-Y.; Ma, H. M.

1992-01-01

165

Characterization of biocontrol traits in the entomopathogenic nematode Heterorhabditis georgiana (Kesah strain), and phylogenetic analysis of the nematode's symbiotic bacteria.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Our objective was to estimate the biocontrol potential of the recently discovered entomopathogenic nematode species, Heterorhabditis georgiana (Kesha strain). Virulence and environmental tolerance were tested among several nematode species. Heterorhabditis georgiana expressed low or intermediate c...

166

How to identify nematode problems and why it is important  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plant-parasitic nematodes are microscopic worms that feed on plants. Several nematode species are serious pathogens of cotton, reducing overall US cotton production by an estimated 4.7%. Though losses in nematode infested fields are frequently 10 to 30%, losses can be greater than 50%. Cotton pla...

167

Site-Specific Detection and Management of Nematodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nematode distribution varies significantly throughout a field and is highly correlated to soil texture and other edaphic factors. Field-wide application results in nematicides being applied to areas without nematodes and the application of sub-effective levels in areas with high nematode densities. ...

168

Directional movement of entomopathogenic nematodes in response to electrical current  

Technology Transfer Automated Retrieval System (TEKTRAN)

Entomopathogenic nematodes in the genera Steinernema and Heterorhabditis are important regulating agents of insect populations. The infective juvenile nematodes respond to a variety of stimuli that aid in survival and host finding. Identification of novel cues in the nematodes’ environment can help ...

169

Texture Analysis for Nematode Genera Classification Bilson Jake Libres Campana  

E-print Network

by a single nematode genus and billions of dollars of yearly agricultural damage can be attributed to just, and efficiency of this process. This paper focuses on classifying microscopic nematodes. This presents additional classification of a sample's genus due to their structure. Nematode images are attained using video capture

Zordan, Victor

170

CONTROLLING BANDED ASH CLEARWING MOTH BORER USING ENTOMOPATHOGENIC NEMATODES  

Microsoft Academic Search

The banded ash clearwing moth, Podosesia aureocincta, in 24 green ash growing in a nursery were treated with the nematode, Steinernema carpocapsae (strain 25) at two different rates. Eight infested green ash were controls in the field trial. Nematodes were applied in July using a back- pack sprayer. Applications of entomopathogenic nematodes significantly reduced the number of living larvae associated

Stanton Gill; John Davidson; Wanda MacLachian; Will Potts

171

EFFECTS OF PRE-PLANT SOIL TREATMENTS ON NEMATODE COMMUNITIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

While nematodes play important roles in soil nutrient cycling, many pre-plant soil management practices act as perturbations to nematode communities. A 2-year field trial was conducted to examine nematode communities in soil treated with methyl bromide (MB), 6-week solarization (S), cowpea cover cro...

172

PEST&CROP INDEX 2011 INSECTS, MITES & NEMATODES  

E-print Network

for Yellowing of Soybeans - 14 #12;Millipede Nematodes Nematode Updates ­ Needle Nematodes on Wheat ­ 2 Potato Stalk Borer Stink Bug Western Bean Cutworm Entomologist: Winter Not Likely to Slow Corn Pest's Advance/Wild Onion Control in Wheat ­ 2 Marestail Control Essential to Protect Soybean Yields ­ 3 Poison Hemlock

Ginzel, Matthew

173

A novel flavivirus in the soybean cyst nematode  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heterodera glycines, the soybean cyst nematode (SCN) is a subterranean root pathogen that causes the most damaging disease of soybean in the United States. A novel nematode virus genome, soybean cyst nematode virus 5 (SbCNV5), was identified in RNASeq data from SCN eggs and second-stage juveniles. T...

174

The pathogenesis of optic neuritis caused by Angiostrongylus cantonensis in BALB/c mice  

PubMed Central

Background One of the most common causes of meningitis in South East Asia is angiostrongyliasis or infection by the parasitic nematode Angiostrongyliasis cantonensis. Although this nematode usually resides in the pulmonary arteries of rats, its incidental occurence in other hosts such as humans can cause optic neuritis and lead to serious vision sequelae. Nevertheless, there are currently no systematic studies conducted in this area. Methods In order to study the pathogenesis of optic neuritis, mice were tried as a new animal model to study and challenge with A. cantonensis on 7d, 14d and 21d, respectively. Electroretinogram (ERG), visual evoked potential (VEP), ophthalmoscopy and histology were examined on day 7d, 14d and 21d and tribendimidine (TBD) was later used to treat optic neuritis on day 14d for a week to evaluate its therapeutic effects. Results Infection of A. cantonensis caused obvious inflammatory cell infiltration in the retina and optic nerve adventitia in day 14d and 21d followed by optic nerve fiber demyelination and retinal ganglion swelling at day 21d in the challenged mice. Prolonged VEP latency and decreased ERG amplitude were also observed on day 21. After treatment of TBD in the infected mice, retinal and optic nerve inflammation were alleviated, but VEP latency and ERG amplitude did not improve on day 21d and 28d. Conclusions The current study provides evidence that A. cantonensis can cause optic neuritis along with optic nerve demyelination and retinal ganglion cell damage in a mouse model. TBD alone treatment can improve the symptoms of optic neuritis, but does not aid in vision recovery, suggesting that both neuroprotective agents and Dexamethasone should be administered, along with treatment for the infection, to protect the optic nerve and ganglion cells. Furthermore, as the symptoms of optic neuritis caused by A. cantonensis in mice are similar to the optic neuritis in multiple sclerosis (MS) human patients, we suggest that the BALB/c mouse model provided in this study may be useful to explore therapies of optic neuritis in MS patients. PMID:25052055

2014-01-01

175

Theory of the locomotion of nematodes  

PubMed Central

We develop a model of the undulatory locomotion of nematodes, in particular that of Caenorhabditis elegans, based on mechanics. The model takes into account the most important forces acting on a moving worm and allows the computer simulation of a creeping nematode. These forces are produced by the interior pressure in the liquid-filled body cavity, the elasticity of the cuticle, the excitation of certain sets of muscles and the friction between the body and its support. We propose that muscle excitation patterns can be generated by stretch receptor control. By solving numerically the equations of motion of the model of the nematode, we demonstrate that these muscle excitation patterns are suitable for the propulsion of the animal. PMID:19431807

Niebur, Ernst; Erdös, Paul

1991-01-01

176

Nematode problems affecting agriculture in the Philippines.  

PubMed

Nematodes are considered major pests on most economic crops in the Philippines, particularly on banana, pineapple, citrus, tomato, ramie, and sugarcane. Radopholus similis is the most destructive nematode on banana, while Meloidogyne spp. are more serious on various vegetable crops such as tomato, okra, and celery and on fiber crops such as ramie. Tylenchulus semipenetrans is a problem on citrus and Rotylenchulus reniformis on pineapple and some legume crops. Hirschmanniella oryzae and Aphelenchoides besseyi are becoming serious on rice, and Pratylenchus zeae is affecting corn in some areas. Lately, Globodera rostochiensis has been causing serious damage on potato in the highlands. Control measures such as crop rotation, planting resistant varieties, chemical nematicide application, and biological control have been recommended to control these nematodes. PMID:19290204

Davide, R G

1988-04-01

177

Nematode Problems Affecting Agriculture in the Philippines  

PubMed Central

Nematodes are considered major pests on most economic crops in the Philippines, particularly on banana, pineapple, citrus, tomato, ramie, and sugarcane. Radopholus similis is the most destructive nematode on banana, while Meloidogyne spp. are more serious on various vegetable crops such as tomato, okra, and celery and on fiber crops such as ramie. Tylenchulus semipenetrans is a problem on citrus and Rotylenchulus reniformis on pineapple and some legume crops. Hirschmanniella oryzae and Aphelenchoides besseyi are becoming serious on rice, and Pratylenchus zeae is affecting corn in some areas. Lately, Globodera rostochiensis has been causing serious damage on potato in the highlands. Control measures such as crop rotation, planting resistant varieties, chemical nematicide application, and biological control have been recommended to control these nematodes. PMID:19290204

Davide, R. G.

1988-01-01

178

Assessment of nematode biodiversity using DGGE of 18S rDNA following extraction of nematodes from soil  

Microsoft Academic Search

Soil nematodes are both taxonomically and functionally diverse, respond quickly to soil perturbation and have much potential as indicators of soil health. However, because of the perceived difficulty of identifying nematodes to species level morphologically, they are frequently neglected in soil ecological studies. Recently, extraction of soil DNA, amplification of 18S rDNA genes using nematode consensus primers and subsequent separation

Aude L. J. L. Foucher; Tom Bongers; Leslie R. Noble; Michael J. Wilson

2004-01-01

179

Matrix metalloproteinase-9 leads to blood-brain barrier leakage in mice with eosinophilic meningoencephalitis caused by Angiostrongylus cantonensis.  

PubMed

Blood-brain barrier (BBB) disruption is associated with tight junction protein degradation, basal membrane disruption, and astrocyte damage. This study aims to investigate the role of matrix metalloproteinase (MMP)-9 in BBB disruption during Angiostrongylus cantonensis infection. We used mice infected with A. cantonensis, in which parasite-induced eosinophilia and inflammation might induce MMP-9 elevation. MMP-9 could cause claudin-5 degradation in endothelium tight junction, collagen type IV degradation in basal membranes, and S100B degradation in astrocytes of wild-type mice. BBB permeability was significantly attenuated in MMP-9 knockout mice than in wild-type mice in angiostrongyliasis meningoencephalitis. Immune cell aggregates were also more attenuated in the brains of MMP-9 knockout mice than in the brains of wild-type mice. Results suggest that MMP-9 activities are significant in BBB disruption in angiostrongyliasis meningoencephalitis. This study improves understanding of molecular mechanisms that underlie brain invasion by A. cantonensis, which is a key step in the pathogenesis of meningoencephalitis, and can offer a new strategy to reduce mortality. PMID:25158284

Chiu, Ping-Sung; Lai, Shih-Chan

2014-12-01

180

The use of albendazole and diammonium glycyrrhizinate in the treatment of eosinophilic meningitis in mice infected with Angiostrongylus cantonensis.  

PubMed

Angiostrongylus cantonensis (A. cantonensis) infection causes eosinophilic meningitis in humans. Eosinophilia and a Th2-type immune response are the crucial immune mechanisms for eosinophilic meningitis. CD4+CD25+ regulatory T cells (Treg) are involved in the pathogenesis of A. cantonensis. Diammonium glycyrrhizinate (DG) is a compound related to glycyrrhizin (GL), a triterpene glycoside extracted from liquorice root. We investigated the curative effects and probable mechanisms of therapy involving a combination of albendazole and DG in BALB/c mice infected with A. cantonensis, and compared these with therapy involving albendazole and dexamethasone. We analysed survival time, body weight, signs, eosinophil numbers, immunoglobulin E (IgE), interleukin-5 (IL-5), and eotaxin concentrations, numbers and Foxp3 expression of CD4+CD25+ Treg, worm recovery and histopathology. The present results demonstrated that the combination of albendazole and DG could increase survival time more efficiently and relieve neurological dysfunction; decrease weight loss, eosinophil numbers, concentrations of IgE, IL-5 and eotaxin, the number and expression of Foxp3 of CD4+CD25+ Treg; and improve worm recovery and histopathology changes in treated animals, compared with the combination of albendazole and dexamethasone. The observations presented here suggest that the albendazole and dexamethasone combination could be replaced by the combination of albendazole and DG. PMID:22152396

Li, Y; Tang, J-P; Chen, D-R; Fu, C-Y; Wang, P; Li, Z; Wei, W; Li, H; Dong, W-Q

2013-03-01

181

Cryopreservation of roe deer abomasal nematodes for morphological identification.  

PubMed

Conventional methods to preserve adult nematodes for taxonomic purposes involve the use of fixative or clearing solutions (alcohol, formaldehyde, AFA and lactophenol), which cause morphological alterations and are toxic. The aim of this study is to propose an alternative method based on glycerol-cryopreservation of nematodes for their subsequent identification. Adults of trichostrongylid nematodes from the abomasum of roe deer (Capreolus capreolus Linnaeus) were glycerol-cryopreserved and compared with those fixed in formaldehyde, fresh and frozen without cryoprotectans. Morphology, transparency and elasticity of the anterior and posterior portion of male nematodes were compared, especially the caudal cuticular bursa and genital accessories. The method presented is quick and easy to use, and the quality of nematode specimens is better than that of nematodes fixed by previously used fixatives. Moreover, glycerol cryopreserved nematodes can be stored for a long time at -20 degrees C in perfect condition and they could be suitable for further analyses, such as histological or ultrastructural examinations. PMID:24684056

Beraldo, Paola; Pascotto, Ernesto

2014-02-01

182

Molecular phylogeny of beetle associated diplogastrid nematodes suggests host switching rather than nematode-beetle coevolution  

PubMed Central

Background Nematodes are putatively the most species-rich animal phylum. They have various life styles and occur in a variety of habitats, ranging from free-living nematodes in aquatic or terrestrial environments to parasites of animals and plants. The rhabditid nematode Caenorhabditis elegans is one of the most important model organisms in modern biology. Pristionchus pacificus of the family of the Diplogastridae has been developed as a satellite model for comparison to C. elegans. The Diplogastridae, a monophyletic clade within the rhabditid nematodes, are frequently associated with beetles. How this beetle-association evolved and whether beetle-nematode coevolution occurred is still elusive. As a prerequisite to answering this question a robust phylogeny of beetle-associated Diplogastridae is needed. Results Sequences for the nuclear small subunit ribosomal RNA and for 12 ribosomal protein encoding nucleotide sequences were collected for 14 diplogastrid taxa yielding a dataset of 5996 bp of concatenated aligned sequences. A molecular phylogeny of beetle-associated diplogastrid nematodes was established by various algorithms. Robust subclades could be demonstrated embedded in a phylogenetic tree topology with short internal branches, indicating rapid ancestral divergences. Comparison of the diplogastrid phylogeny to a comprehensive beetle phylogeny revealed no major congruence and thus no evidence for a long-term coevolution. Conclusion Reconstruction of the phylogenetic history of beetle-associated Diplogastridae yields four distinct subclades, whose deep phylogenetic divergence, as indicated by short internal branch lengths, shows evidence for evolution by successions of ancient rapid radiation events. The stem species of the Diplogastridae existed at the same time period when the major radiations of the beetles occurred. Comparison of nematode and beetle phylogenies provides, however, no evidence for long-term coevolution of diplogastrid nematodes and their beetle hosts. Instead, frequent host switching is observed. The molecular phylogeny of the Diplogastridae provides a framework for further examinations of the evolution of these associations, for the study of interactions within the ecosystems, and for investigations of diplogastrid genome evolution. PMID:19703296

2009-01-01

183

A CUTANEOUS NEMATODE INFECTION IN MONKEYS  

PubMed Central

A number of monkeys (Macacus rhesus) were found to be infected with a nematode which gave rise to several types of skin lesions, subcutaneous nodules, edema about the joints, and elongated serpiginous blisters of the palms and soles. In the subcutaneous nodules were found larval forms of the nematode and possibly adult male forms. The reaction about these worms consisted of proliferation of fixed cells, and invasion of eosinophils, with subsequent presence of giant cells, young blood vessels, and finally capsule formation; eventually the worms were killed, eliminated, and the nodule disappeared. In the skin of the palms and soles the adult female worm burrowed in the epidermis, producing an elongated serpiginous blood blister that eventually became purulent. In this blister the worm laid her eggs; and by the bursting of the blister the eggs were discharged into the outer world and placed in a position to infect new hosts. The reaction in the epidermis was evidently not severe enough to interfere seriously with the health of the host or with the continuation of the egg-bearing period of the female parasite. This condition of almost perfect parasitism is an ideal one for the continuation of the life of this species of nematode. In so far as we are able to determine this is the first description of a nematode that lays its eggs in the epidermis. The provisional name of the parasite is Trichosoma cutaneum, 1922. PMID:19868631

Swift, Homer F.; Boots, Ralph H.; Miller, C. Philip

1922-01-01

184

Nematodes: Model Organisms in High School Biology  

ERIC Educational Resources Information Center

In a collaborative effort between university researchers and high school science teachers, an inquiry-based laboratory module was designed using two species of insecticidal nematodes to help students apply scientific inquiry and elements of thoughtful experimental design. The learning experience and model are described in this article. (Contains 4…

Bliss, TJ; Anderson, Margery; Dillman, Adler; Yourick, Debra; Jett, Marti; Adams, Byron J.; Russell, RevaBeth

2007-01-01

185

Key to nematodes reported in waterfowl  

USGS Publications Warehouse

This key, covering 171 species and subspecies of nematodes in 49 genera, is based on the the listings in the author's "Catalogue of Helminths of Waterfowl" (McDonald, 1969b), but includes 19 additional forms from his continuing survey of new literature.

McDonald, Malcolm E.

1974-01-01

186

MSP Dynamics Drives Nematode Sperm Locomotion  

Microsoft Academic Search

Most eukaryotic cells can crawl over surfaces. In general, this motility requires three sequential actions: polymerization at the leading edge, adhesion to the substrate, and retraction at the rear. Recent in vitro experiments with extracts from spermatozoa from the nematode Ascaris suum suggest that retraction forces are generated by depolymerization of the major sperm protein cytoskeleton. Combining polymer entropy with

Charles W. Wolgemuth; Long Miao; Orion Vanderlinde; Tom Roberts; George Osterz

2005-01-01

187

Serum concentrations of vitamin D metabolites, vitamins A and E, and carotenoids in six canid and four ursid species at four zoos.  

PubMed

Nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. The species analyzed included: African wild dog (Lycaon pictus), arctic fox (Alopex lagopus), gray wolf (Canis lupus), maned wolf (Chrysocyon brachyurus), Mexican wolf (Canis lupus baleiyi), red wolf (Canis rufus), brown bear (Ursus arctos), polar bear (Ursus maritimus), spectacled bear (Tremarctos ornatus), and sun bear (Ursus malayanus). Diet information was collected for these animals from each participating zoo (Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens, and North Carolina Zoological Park). The nutritional composition of the diet for each species at each institution met probable dietary requirements. Blood samples were collected from each animal and analyzed for vitamin D metabolites 25(OH)D and 1,25(OH)(2)D, vitamin A (retinol, retinyl stearate, retinyl palmitate), vitamin E (alpha-tocopherol and gamma-tocopherol) and selected carotenoids. Family differences were found for 25(OH)D, retinol, retinyl stearate, retinyl palmitate and gamma-tocopherol. Species differences were found for all detectable measurements. Carotenoids were not detected in any species. The large number of animals contributing to these data, provides a substantial base for comparing the nutritional status of healthy animals and the differences among them. PMID:11137448

Crissey, S; Ange, K; Slifka, K; Bowen, P; Stacewicz-Sapuntzakis, M; Langman, C; Sadler, W; Ward, A

2001-01-01

188

Top 10 plant-parasitic nematodes in molecular plant pathology.  

PubMed

The aim of this review was to undertake a survey of researchers working with plant-parasitic nematodes in order to determine a 'top 10' list of these pathogens based on scientific and economic importance. Any such list will not be definitive as economic importance will vary depending on the region of the world in which a researcher is based. However, care was taken to include researchers from as many parts of the world as possible when carrying out the survey. The top 10 list emerging from the survey is composed of: (1) root-knot nematodes (Meloidogyne spp.); (2) cyst nematodes (Heterodera and Globodera spp.); (3) root lesion nematodes (Pratylenchus spp.); (4) the burrowing nematode Radopholus similis; (5) Ditylenchus dipsaci; (6) the pine wilt nematode Bursaphelenchus xylophilus; (7) the reniform nematode Rotylenchulus reniformis; (8) Xiphinema index (the only virus vector nematode to make the list); (9) Nacobbus aberrans; and (10) Aphelenchoides besseyi. The biology of each nematode (or nematode group) is reviewed briefly. PMID:23809086

Jones, John T; Haegeman, Annelies; Danchin, Etienne G J; Gaur, Hari S; Helder, Johannes; Jones, Michael G K; Kikuchi, Taisei; Manzanilla-López, Rosa; Palomares-Rius, Juan E; Wesemael, Wim M L; Perry, Roland N

2013-12-01

189

Nitrogen Addition Regulates Soil Nematode Community Composition through Ammonium Suppression  

PubMed Central

Nitrogen (N) enrichment resulting from anthropogenic activities has greatly changed the composition and functioning of soil communities. Nematodes are one of the most abundant and diverse groups of soil organisms, and they occupy key trophic positions in the soil detritus food web. Nematodes have therefore been proposed as useful indicators for shifts in soil ecosystem functioning under N enrichment. Here, we monitored temporal dynamics of the soil nematode community using a multi-level N addition experiment in an Inner Mongolia grassland. Measurements were made three years after the start of the experiment. We used structural equation modeling (SEM) to explore the mechanisms regulating nematode responses to N enrichment. Across the N enrichment gradient, significant reductions in total nematode abundance, diversity (H' and taxonomic richness), maturity index (MI), and the abundance of root herbivores, fungivores and omnivores-predators were found in August. Root herbivores recovered in September, contributing to the temporal variation of total nematode abundance across the N gradient. Bacterivores showed a hump-shaped relationship with N addition rate, both in August and September. Ammonium concentration was negatively correlated with the abundance of total and herbivorous nematodes in August, but not in September. Ammonium suppression explained 61% of the variation in nematode richness and 43% of the variation in nematode trophic group composition. Ammonium toxicity may occur when herbivorous nematodes feed on root fluid, providing a possible explanation for the negative relationship between herbivorous nematodes and ammonium concentration in August. We found a significantly positive relationship between fungivores and fungal phospholipid fatty acids (PLFA), suggesting bottom-up control of fungivores. No such relationship was found between bacterivorous nematodes and bacterial PLFA. Our findings contribute to the understanding of effects of N enrichment in semiarid grassland on soil nematode trophic groups, and the cascading effects in the detrital soil food web. PMID:22952671

Wei, Cunzheng; Zheng, Huifen; Li, Qi; Lü, Xiaotao; Yu, Qiang; Zhang, Haiyang; Chen, Quansheng; He, Nianpeng; Kardol, Paul; Liang, Wenju; Han, Xingguo

2012-01-01

190

7 CFR 301.85-9 - Movement of live golden nematodes.  

Code of Federal Regulations, 2012 CFR

... false Movement of live golden nematodes. 301.85-9 Section 301.85-9 Agriculture...DOMESTIC QUARANTINE NOTICES Golden Nematode Quarantine and Regulations...85-9 Movement of live golden nematodes....

2012-01-01

191

7 CFR 301.85-9 - Movement of live golden nematodes.  

Code of Federal Regulations, 2010 CFR

... false Movement of live golden nematodes. 301.85-9 Section 301.85-9 Agriculture...DOMESTIC QUARANTINE NOTICES Golden Nematode Quarantine and Regulations...85-9 Movement of live golden nematodes....

2010-01-01

192

7 CFR 301.85-9 - Movement of live golden nematodes.  

Code of Federal Regulations, 2011 CFR

... false Movement of live golden nematodes. 301.85-9 Section 301.85-9 Agriculture...DOMESTIC QUARANTINE NOTICES Golden Nematode Quarantine and Regulations...85-9 Movement of live golden nematodes....

2011-01-01

193

7 CFR 301.85-9 - Movement of live golden nematodes.  

Code of Federal Regulations, 2014 CFR

... false Movement of live golden nematodes. 301.85-9 Section 301.85-9 Agriculture...DOMESTIC QUARANTINE NOTICES Golden Nematode Quarantine and Regulations...85-9 Movement of live golden nematodes....

2014-01-01

194

7 CFR 301.85-9 - Movement of live golden nematodes.  

Code of Federal Regulations, 2013 CFR

... false Movement of live golden nematodes. 301.85-9 Section 301.85-9 Agriculture...DOMESTIC QUARANTINE NOTICES Golden Nematode Quarantine and Regulations...85-9 Movement of live golden nematodes....

2013-01-01

195

Rolling Circle Amplification of Complete Nematode Mitochondrial Genomes  

PubMed Central

To enable investigation of nematode mitochondrial DNA evolution, methodology has been developed to amplify intact nematode mitochondrial genomes in preparative yields using a rolling circle replication strategy. Successful reactions were generated from whole cell template DNA prepared by alkaline lysis of the rhabditid nematode Caenorhabditis elegans and a mermithid nematode, Thaumamermis cosgrovei. These taxa, representing the two major nematode classes Chromodorea and Enoplea, maintain mitochondrial genomes of 13.8 kb and 20.0 kb, respectively. Efficient amplifications were conducted on template DNA isolated from individual or pooled nematodes that were alive or stored at -80°C. Unexpectedly, these experiments revealed that multiple T. cosgrovei mitochondrial DNA haplotypes are maintained in our local population. Rolling circle amplification products can be used as templates for standard PCR reactions with specific primers that target mitochondrial genes or for direct DNA sequencing. PMID:19262866

Tang, Sha; Hyman, Bradley C.

2005-01-01

196

An 8-week brain MRI follow-up analysis of rat eosinophilic meningitis caused by Angiostrongylus cantonensis infection.  

PubMed

Early differential diagnosis and timely follow-up are advantageous in the management of Angiostrongylus cantonensis infection. This study aimed to characterize angiostrongyliasis in the rat brain for an 8-week period using magnetic resonance imaging (MRI) with contrast-enhanced T1-weighted images (T1WI), T2-weighted imaging (T2WI), fluid attenuation inversion recovery (FLAIR) and R2 mapping sequences. The data were analysed with Mathematica and Matlab software programs for weekly changes in each brain following the infection of 20, 50, 100 and 300 third-stage larvae (L3), respectively. The results showed that the average subarachnoid space detected by T2WI technique was peaked up to 10% increase of original size on day 35 after 100 or 300 larvae infection, while those infected with 20 or 50 larvae showed less than 4% increase during the entire course of observation. This increase was relevant to the mortality of the infected rats, because those with 100 or 300 larvae infections showed a sharp decrease in survival rate before day 40. After day 40, the average subarachnoid space was decreased, but the average ventricle size was persistently increased, with the highest increase observed in the group infected with 300 larvae on day 56. Furthermore, the R2 mapping mean and R2 mapping size were significantly different between the brains with severe infection (100 and 300 larvae groups together) and those with mild infection (20 and 50 larvae groups together) on day 49, but not on day 35. Our results showed that diagnosis for different quantity of larvae infection using MRI is possible and follow-up characterization is informative in revealing the effects of angiostrongyliasis on different brain areas. In conclusion, our results support the use of MRI as a non-invasive diagnostic technique for eosinophilic meningitis caused by A. cantonensis infection. PMID:24207053

Shyu, L Y; Tsai, H H; Lin, D P; Chang, H H; Tyan, Y S; Weng, J C

2014-09-01

197

Association of the Red Ring Nematode and Other Nematode Species with the Palm Weevil, Rhynchophorus palmarum.  

PubMed

The palm weevil, Rhynchophorus palmarum (L.), was collected in cocoons from red ring-diseased coconut palms (Cocos nucifera L.) in Trinidad and Tobago. Juveniles of five species of nematodes were extracted from the genitalia and macerated bodies of newly emerged adults of the palm weevil: Rhadinaphelenchus cocophilus (Cobb) Goodey (the red ring nematode), Teratorhabditis sp., Diplogasteritus sp., Mononchoides sp., and Bursaphelenchus sp. Over 90% of newly emerged weevil females and males were infested internally with red ring nematode juveniles, and over 47% of the weevils contained more than 1,000 red ring nematodes each. There was no significant correlation between weevil body length and the number of red ring nematodes carried internally by each weevil. Teratorhabditis sp. and Diplogasteritus sp. were extracted from over 50% of the palm weevils, and Monochoides sp. and Bursaphelenchus sp. were found in a small proportion of the weevils. Field-collected adult weevils were also internally and externally infested with a Rhabditis sp., which was not observed in or on weevils allowed to emerge from field-collected cocoons. PMID:19287703

Gerber, K; Giblin-Davis, R M

1990-04-01

198

Association of the Red Ring Nematode and Other Nematode Species with the Palm Weevil, Rhynchophorus palmarum  

PubMed Central

The palm weevil, Rhynchophorus palmarum (L.), was collected in cocoons from red ring-diseased coconut palms (Cocos nucifera L.) in Trinidad and Tobago. Juveniles of five species of nematodes were extracted from the genitalia and macerated bodies of newly emerged adults of the palm weevil: Rhadinaphelenchus cocophilus (Cobb) Goodey (the red ring nematode), Teratorhabditis sp., Diplogasteritus sp., Mononchoides sp., and Bursaphelenchus sp. Over 90% of newly emerged weevil females and males were infested internally with red ring nematode juveniles, and over 47% of the weevils contained more than 1,000 red ring nematodes each. There was no significant correlation between weevil body length and the number of red ring nematodes carried internally by each weevil. Teratorhabditis sp. and Diplogasteritus sp. were extracted from over 50% of the palm weevils, and Monochoides sp. and Bursaphelenchus sp. were found in a small proportion of the weevils. Field-collected adult weevils were also internally and externally infested with a Rhabditis sp., which was not observed in or on weevils allowed to emerge from field-collected cocoons. PMID:19287703

Gerber, Karin; Giblin-Davis, Robin M.

1990-01-01

199

Computational and phylogenetic validation of nematode horizontal gene transfer.  

PubMed

Sequencing of expressed genes has shown that nematodes, particularly the plant-parasitic nematodes, have genes purportedly acquired from other kingdoms by horizontal gene transfer. The prevailing orthodoxy is that such transfer has been a driving force in the evolution of niche specificity, and a recent paper in BMC Evolutionary Biology that presents a detailed phylogenetic analysis of cellulase genes in the free-living nematode Pristionchus pacificus at the species, genus and family levels substantiates this hypothesis. PMID:21342537

Scholl, Elizabeth H; Bird, David McK

2011-01-01

200

Ectoparasitic acugutturid nematodes of adult lepidoptera.  

PubMed

Noctuidonema guyaneme is an interesting ectoparasite of adult Lepidoptera that feeds on hosts from at least five families with its long stylet. Noctuidonema guyanense spends its entire life on the adult moth and is sustained as it is passed from moth to moth during host mating. Overlapping host generations are essential for parasite survival. This nematode occurs throughout tropical and subtropical America and is transported by at least one of its hosts, Spodoptera frugiperda, during migration to northern sites in the United States each spring. Noctuidonema guyanense debilitates its hosts. Research conducted to help determine the biological control importance of this nematode is reviewed. Two additional species, N. daptria and N. dibolia, are now known for Noctuidonema. PMID:19277339

Simmons, A M; Rogers, C E

1996-03-01

201

Weather and the ecology of bursate nematodes  

Microsoft Academic Search

The free-living stages of bursate nematodes are affected in different ways by meteorological factors. The eggs and 1st and 2nd stage larvae live in the feces, and these factors act on them through the feces. The embryo in the egg is protected by the eggshell. The 1st and 2nd stage larvae feed on micro-organisms, and are affected by the species

N. D. Levine

1980-01-01

202

Engineering Natural and Synthetic Resistance for Nematode Management  

PubMed Central

Bioengineering strategies are being developed that will provide specific and durable resistance against plant-parasitic nematodes in crops. The strategies come under three categories: (i) transfer of natural resistance genes from plants that have them to plants that do not, to mobilize the defense mechanisms in susceptible crops; (ii) interference with the biochemical signals that nematodes exchange with plants during parasitic interactions, especially those resulting in the formation of specialized feeding sites for the sedentary endoparasites—many nematode genes and many plant genes are potential targets for manipulation; and (iii) expression in plant cells of proteins toxic to nematodes. PMID:19270915

Vrain, Thierry C.

1999-01-01

203

Assaying Environmental Nickel Toxicity Using Model Nematodes  

PubMed Central

Although nickel exposure results in allergic reactions, respiratory conditions, and cancer in humans and rodents, the ramifications of excess nickel in the environment for animal and human health remain largely undescribed. Nickel and other cationic metals travel through waterways and bind to soils and sediments. To evaluate the potential toxic effects of nickel at environmental contaminant levels (8.9-7,600 µg Ni/g dry weight of sediment and 50-800 µg NiCl2/L of water), we conducted assays using two cosmopolitan nematodes, Caenorhabditis elegans and Pristionchus pacificus. We assayed the effects of both sediment-bound and aqueous nickel upon animal growth, developmental survival, lifespan, and fecundity. Uncontaminated sediments were collected from sites in the Midwestern United States and spiked with a range of nickel concentrations. We found that nickel-spiked sediment substantially impairs both survival from larval to adult stages and adult longevity in a concentration-dependent manner. Further, while aqueous nickel showed no adverse effects on either survivorship or longevity, we observed a significant decrease in fecundity, indicating that aqueous nickel could have a negative impact on nematode physiology. Intriguingly, C. elegans and P. pacificus exhibit similar, but not identical, responses to nickel exposure. Moreover, P. pacificus could be tested successfully in sediments inhospitable to C. elegans. Our results add to a growing body of literature documenting the impact of nickel on animal physiology, and suggest that environmental toxicological studies could gain an advantage by widening their repertoire of nematode species. PMID:24116204

Rudel, David; Douglas, Chandler D.; Huffnagle, Ian M.; Besser, John M.; Ingersoll, Christopher G.

2013-01-01

204

Reniform Nematode Resistance in Selected Soybean Cultivars  

PubMed Central

Two hundred eighty-two soybean cultivars from the variety testing programs of Arkansas and Mississippi were tested in greenhouse pot experiments during summer 1998 to identify soybean cultivars with resistance to the reniform nematode, Rotylenchulus reniformis. Also included in the tests were the resistant cultivars Forrest and Hartwig, the susceptible control Braxton, and fallow infested soil, which were used as controls. Numbers of reniform nematode extracted from the soil and roots and the ratio of the numbers reproducing on each cultivar compared to the number reproducing on Forrest are reported. Cultivars with reproduction not significantly different from Forrest were classified resistant, whereas those with greater reproductive indices were considered susceptible. One of the 18 cultivars of relative maturity group (RMG) ?4.4 was classified as resistant. For the 86 cultivars of RMG 4.5-4.9, 18 were found to be resistant. Of the 43 cultivars of RMG 5.0-5.4, 16 were resistant, while 43 of the 91 cultivars of RMG 5.5-5.9 were resistant. Fifteen of the cultivars with an RMG of ?6.0 were classed as resistant. These data will be useful in the selection of soybean cultivars to use in rotation with cotton to help control the reniform nematode. PMID:19270934

Robbins, R. T.; Rakes, L.; Jackson, L. E.; Dombek, D. G.

1999-01-01

205

Cyclotide Interactions with the Nematode External Surface?  

PubMed Central

Cyclotides are a large family of cyclic cystine knot-containing plant peptides that have anthelminthic activities against Haemonchus contortus and Trichostrongylus colubriformis, two important gastrointestinal nematodes of sheep. In this study, we investigated the interaction of the prototypic cyclotide kalata B1 with the external surface of H. contortus larvae and adult worms. We show that cyclotides do not need to be ingested by the worms to exert their toxic effects but that an interaction with the external surface alone is toxic. Evidence for this was the toxicity toward adult worms in the presence of a chemically induced pharyngeal ligature and toxicity of cyclotides toward nonfeeding larval life stages. Uptake of tritiated inulin in ligated adult worms was increased in the presence of cyclotide, suggesting that cyclotides increase the permeability of the external membranes of adult nematodes. Polyethylene glycols of various sizes showed protective effects on the nonfeeding larval life stage, as well as in hemolytic activity assays, suggesting that discrete pores are formed in the membrane surfaces by cyclotides and that these can be blocked by polyethylene glycols of appropriate size. This increased permeability is consistent with recently reported effects of cyclotides on membranes in which kalata B1 was demonstrated to form pores and cause leakage of vesicle/cellular contents. Our data, together with known size constraints on the movement of permeants across nematode cuticle layers, suggest that one action of the cyclotides involves an interaction with the lipid-rich epicuticle layer at the surface of the worm. PMID:20211894

Colgrave, Michelle L.; Huang, Yen-Hua; Craik, David J.; Kotze, Andrew C.

2010-01-01

206

Entomopathogenic nematode production and application technology.  

PubMed

Production and application technology is critical for the success of entomopathogenic nematodes (EPNs) in biological control. Production approaches include in vivo, and in vitro methods (solid or liquid fermentation). For laboratory use and small scale field experiments, in vivo production of EPNs appears to be the appropriate method. In vivo production is also appropriate for niche markets and small growers where a lack of capital, scientific expertise or infrastructure cannot justify large investments into in vitro culture technology. In vitro technology is used when large scale production is needed at reasonable quality and cost. Infective juveniles of entomopathogenic nematodes are usually applied using various spray equipment and standard irrigation systems. Enhanced efficacy in EPN applications can be facilitated through improved delivery mechanisms (e.g., cadaver application) or optimization of spray equipment. Substantial progress has been made in recent years in developing EPN formulations, particularly for above ground applications, e.g., mixing EPNs with surfactants or polymers or with sprayable gels. Bait formulations and insect host cadavers can enhance EPN persistence and reduce the quantity of nematodes required per unit area. This review provides a summary and analysis of factors that affect production and application of EPNs and offers insights for their future in biological insect suppression. PMID:23482883

Shapiro-Ilan, David I; Han, Richou; Dolinksi, Claudia

2012-06-01

207

Entomopathogenic Nematode Production and Application Technology  

PubMed Central

Production and application technology is critical for the success of entomopathogenic nematodes (EPNs) in biological control. Production approaches include in vivo, and in vitro methods (solid or liquid fermentation). For laboratory use and small scale field experiments, in vivo production of EPNs appears to be the appropriate method. In vivo production is also appropriate for niche markets and small growers where a lack of capital, scientific expertise or infrastructure cannot justify large investments into in vitro culture technology. In vitro technology is used when large scale production is needed at reasonable quality and cost. Infective juveniles of entomopathogenic nematodes are usually applied using various spray equipment and standard irrigation systems. Enhanced efficacy in EPN applications can be facilitated through improved delivery mechanisms (e.g., cadaver application) or optimization of spray equipment. Substantial progress has been made in recent years in developing EPN formulations, particularly for above ground applications, e.g., mixing EPNs with surfactants or polymers or with sprayable gels. Bait formulations and insect host cadavers can enhance EPN persistence and reduce the quantity of nematodes required per unit area. This review provides a summary and analysis of factors that affect production and application of EPNs and offers insights for their future in biological insect suppression. PMID:23482883

Shapiro-Ilan, David I.; Han, Richou; Dolinksi, Claudia

2012-01-01

208

Soybean Cyst Nematode in North America - 55 Years Later  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean cyst nematode, Heterodera glycines, was first discovered in North America in 1954 in Hanover County, North Carolina, USA, when it was found on soybean in a field that had been planted to Easter lilies obtained from Japan prior to World War II. The nematode is now distributed throughout soybe...

209

Human Intraocular Filariasis Caused by Pelecitus sp. Nematode, Brazil  

PubMed Central

A male nematode was extracted from iris fibers of a man from the Brazilian Amazon region. This nematode belonged to the genus Pelecitus but was distinct from the 16 known species in this genus. Similarities with Pelecitus spp. from neotropical birds suggested an avian origin for this species. PMID:21529397

Bain, Odile; Diniz, Daniel G.; Nascimento dos Santos, Jeannie; Pinto de Oliveira, Norimar; Frota de Almeida, Izabela Negrão; Frota de Almeida, Rafael Negrão; Frota de Almeida, Luciana Negrão; Dantas-Torres, Filipe; Sobrinho, Edmundo Frota de Almeida

2011-01-01

210

A SURVEY OF CYST NEMATODES (HETERODERA SPP.) IN NORTHERN EGYPT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Information concerning the occurrence and distribution of cyst nematodes (Heterodera spp.) in Egypt is important to assess their potential to cause economic damage to crop plants. A nematode survey was conducted in Alexandria and El-Behera Governorates in northern Egypt to identify the species of cy...

211

Occurrence and distribution of nematodes in Idaho crops  

Technology Transfer Automated Retrieval System (TEKTRAN)

Surveys were conducted in Idaho during the 2000-2006 cropping seasons to study the occurrence, population density, host association and distribution of plant-parasitic nematodes associated with major crops, grasses and weeds. Eighty-four species and 43 genera of plant-parasitic nematodes were record...

212

Correlations of Nematodes and Soil Properties in Soybean Fields  

PubMed Central

Soil samples from 40 soybean fields were collected in 1967 and 1968 and analyzed for nematodes and soil properties. Correlations o f total nematodes, non-stylet nematodes, Dorylaimoidea (excluding Xiphinema americanum), X. americanum, Helicotylenchus pseudorobustus, Tylenchus spp., Aphelenchus avenae, and other groupings of nematodes were made with pH; percentage sand, silt, and clay; percentage organic matter; cation exchange capacity; saturation percentage, and percentage saturation. Organic matter, pH, and cation exchange capacity were most consistently highly correlated with the nematodes. H. pseudorobustus had the most consistently significant correlations with the soil factors. Correlations of nematodes were with more soil factors and were stronger in a wet than in a dry year. The highest numbers of nematodes were usually found in the lighter soils, except in the loamy sand where moisture probably was limiting. In general, soil moisture levels below 20% saturation were probably limiting for most nematodes studied, except for the dorylaims which survived in large numbers in soils with less than 20% saturation. PMID:19322361

Norton, D. C.; Frederick, L. R.; Ponchillia, P. E.; Nyhan, J. W.

1971-01-01

213

Granite Rock Outcrops: An Extreme Environment for Soil Nematodes?  

PubMed Central

We studied soil nematode communities from the surface of granite flatrock outcrops in the eastern Piedmont region of the United States. The thin soils that develop here experience high light intensity and extreme fluctuations in temperature and moisture and host unique plant communities. We collected soils from outcrop microsites in Virginia (VA) and North Carolina (NC) in various stages of succession (Primitive, Minimal, and Mature) and compared soil properties and nematode communities to those of adjacent forest soils. Nematodes were present in most outcrop soils, with densities comparable to forest soils (P > 0.05). Nematode communities in Mature and Minimal soils had lower species richness than forest soils (P < 0.05) and contained more bacterial-feeders and fewer fungal-feeders (P < 0.05). Primitive soils contained either no nematodes (NC) or only a single species (Mesodorylaimus sp., VA). Nematode communities were similar between Mature and Minimal soils, according to trophic group representation, MI, PPI, EI, SI, and CI (P > 0.05). Forest soils had a higher PPI value (P < 0.05), but otherwise community indices were similar to outcrop soils (P > 0.05). Outcrop nematode communities failed to group together in a Bray-Curtis cluster analysis, indicating higher variability in community structure than the Forest soils, which did cluster together. A high proportion of the nematodes were extracted from outcrop soils in coiled form (33-89%), indicating that they used anhydrobiosis to persist in this unique environment. PMID:22661780

Austin, Erin; Semmens, Katharine; Parsons, Charles

2009-01-01

214

Sex-determination gene and pathway evolution in nematodes  

E-print Network

Sex-determination gene and pathway evolution in nematodes Paul Stothard and Dave Pilgrim* Summary at the molecular level. By identifying differences between the sex-determination mechanisms in C. elegans and other nematode species, it should be possible to under- stand how complex sex-determining pathways evolve

McQueen, Heather

215

High Sensitivity NMR and Mixture Analysis for Nematode Behavioral Metabolomics  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nematodes are the most abundant animal on earth, and they parasitize virtually all plants and animals. Caenorhabditis elegans is a free-living nematode that lives in soil and composting material. We have shown that C. elegans releases at least 40 small molecules into its environment including many...

216

Computational and phylogenetic validation of nematode horizontal gene transfer  

Microsoft Academic Search

Sequencing of expressed genes has shown that nematodes, particularly the plant-parasitic nematodes, have genes purportedly acquired from other kingdoms by horizontal gene transfer. The prevailing orthodoxy is that such transfer has been a driving force in the evolution of niche specificity, and a recent paper in BMC Evolutionary Biology that presents a detailed phylogenetic analysis of cellulase genes in the

Elizabeth H Scholl; David McK Bird

2011-01-01

217

Sex-specific mating pheromones in the nematode Panagrellus redivivus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Despite advances in medicine and crop genetics, nematodes remain significant human pathogens and agricultural pests. This warrants investigation of alternative strategies for pest control, such as interference with pheromone-mediated reproduction. Because only two nematode species have had their phe...

218

Book review: Systematics of Cyst Nematodes (Nematoda: Heteroderinae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

The cyst nematodes are an important group of plant-parasitic nematodes that cause billions of dollars in economic damage to crops every year. This article reviews a recently published, two-volume monograph that describes the morphological and molecular characteristics of these agriculturally signif...

219

Nematode resistance and agronomic performance of LONREN and NEMSTACK lines  

Technology Transfer Automated Retrieval System (TEKTRAN)

LONREN lines have resistance to reniform nematodes that was obtained from Gossypium longicalyx. The NEMSTACK lines have the same resistance recombined with the rkn-1 gene for resistance to root knot nematode from 'Acala NemX.' Different LONREN lines vary depending on whether the resistance gene was...

220

Aggregative group behavior in insect parasitic nematode disperal  

Technology Transfer Automated Retrieval System (TEKTRAN)

Movement behavior is critical to determination of spatial ecology and success of foraging in predators and parasites. In this study movement behavior of entomopathogenic nematodes was explored. Movement patterns in sand were investigated when nematodes were applied to a specific locus or when the ne...

221

Characterization of a New Species of Cyst Nematode Parasitizing Corn  

Technology Transfer Automated Retrieval System (TEKTRAN)

Examination of soil around unthrifty corn roots in northwestern Tennessee (Obion County) in 2006 revealed high population densities of juvenile nematodes and lemon-shaped cysts. This nematode resembles Cactodera spp. in possessing a circumfenestrate vulva but lacking bullae and an underbridge. These...

222

Influence of Ragweed ( Ambrosia trifida ) on Plant Parasitic Nematodes  

Microsoft Academic Search

The roots of ragweed Ambrosia trifida exude chemical compounds that have insecticidal activities. This paper reports a survey conducted in a soybean field infested with ragweed to determine if the ragweed affected the populations of plant parasitic nematodes. There was a strong indication that the ragweed decreased populations of plant parasitic nematodes in some cases.

Wei Wang; Xinru Zhu; Weizhi Liu

1998-01-01

223

Original article Parasite nematode infections in Awassi adult sheep  

E-print Network

Original article Parasite nematode infections in Awassi adult sheep: distribution through Syrian were higher in flocks using wet night shelters. nematode / parasite / sheep / Syria / epidemiology Résumé ― Infestations des Ovins Awassi adultes par les nématodes parasites : distribution parmi

Paris-Sud XI, Université de

224

MOLECULAR CHARACTERIZATION OF THE ACTIN GENE FROM CYST NEMATODES IN COMPARISON WITH THOSE FROM OTHER NEMATODES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Actin is an abundant, highly expressed and very conserved protein from the actin/heat shock protein70/sugar kinase superfamily. The full-length mRNA encoding actin was cloned and characterized from the plant-parasitic cyst nematodes Heterodera glycines and Globodera rostochiensis, and from the free-...

225

Antagonists of Plant-parasitic Nematodes in Florida Citrus.  

PubMed

In a survey of antagonists of nematodes in 27 citrus groves, each with a history of Tylenchulus semipenetrans infestation, and 17 noncitrus habitats in Florida, approximately 24 species of microbial antagonists capable of attacking vermiform stages of Radopholus citrophilus were recovered. Eleven of these microbes and a species of Pasteuria also were observed attacking vermiform stages of T. semipenetrans. Verticillium chlamydosporium, Paecilomyces lilacinus, P. marquandii, Streptomyces sp., Arthrobotrys oligospora, and Dactylella ellipsospora were found infecting T. semipenetrans egg masses. Two species of nematophagous amoebae, five species of predatory nematodes, and 29 species of nematophagous arthropods also were detected. Nematode-trapping fungi and nematophagous arthropods were common inhabitants of citrus groves with a history of citrus nematode infestation; however, obligate parasites of nematodes were rare. PMID:19287759

Walter, D E; Kaplan, D T

1990-10-01

226

Co-adaptation mechanisms in plant-nematode systems.  

PubMed

The review is aimed to analyze the biochemical and immune-breaking adaptive mechanisms established in evolution of plant parasitic nematodes. Plant parasitic nematodes are obligate, biotrophic pathogens of numerous plant species. These organisms cause dramatic changes in the morphology and physiology of their hosts. The group of sedentary nematodes which are among the most damaging plant-parasitic nematodes cause the formation of special organs called nematode feeding sites in the root tissue called syncytium (cyst nematodes, CN; Heterodera and Globodera spp.) or giant cells (root-knot nematodes, RKN; Meloidogyne spp.). The most pronounced morphological adaptations of nematodes for plant parasitism include a hollow, protrusible stylet (feeding spear) connected to three esophageal gland cells that express products secreted into plant tissues through the stylet. Several gene products secreted by the nematode during parasitism have been identified. The current battery of candidate parasitism proteins secreted by nematodes to modify plant tissues for parasitism includes cell-wall-modifying enzymes, multiple regulators of host cell cycle and metabolism, proteins that can localize near the plant cell nucleus, potential suppressors of host defense, and mimics of plant molecules. Plants are usually able to recognize and react to parasites by activating various defense responses. When the response of the plant is too weak or too late, a successful infection (compatible interaction) will result. A rapid and strong defense response (e. g. due to the presence of a resistance gene) will result in the resistant (incompatible) reaction. Defense responses include the production of toxic oxygen radicals and systemic signaling compounds as well as the activation of defense genes that lead to the production of structural barriers or other toxins. PMID:25272462

Zinovieva, S V

2014-01-01

227

Pathogenicity of the lesion nematodes on sorghum  

E-print Network

) December 1985 ABSTRACT Pathogenicity of the Lesion Nematodes on Sorghum. (December 1985) Baikabile Motalaote, B. S. , University of Zambia Chairman of Advisory Committee: Dr. James L. Starr R P M t' f ~gt 1 h ~hh lthdf gl P'1'Pj & Shuurmans...-Stekhoven, P. crenatus (Loof), P. coffeae (Zimmermann) Filipjev & Shuurmanns-Stekhoven and P. zeae (Graham) in both ghpt dftld'pit. Pthg 1'tg 1P. 'h~h and P. zeae was studied under greenhouse conditions, and that of P. zeae was also determined in field...

Motalaote, Baikabile

1985-01-01

228

Nematode (Roundworm) Infections in Fish1 Roy P. E. Yanong2  

E-print Network

; and the sites of infection. Even though adult nematodes are typically #12;Nematode (Roundworm) InfectionsCir 91 Nematode (Roundworm) Infections in Fish1 Roy P. E. Yanong2 1. This document is Circular 91 Dean Introduction Nematodes, or roundworms, infect many different species of aquacultured and wild fish

Watson, Craig A.

229

Discovery and initial analysis of novel viral genomes in the soybean cyst nematode  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nematodes are the most abundant multi-cellular animals on earth, yet little is known about their natural viral pathogens and no nematode virus genomes have been published. Consequently, nematode viruses have been overlooked as important biotic factors in the study of nematode ecology. Here we show t...

230

The Apple Snail Pomacea canaliculata, a Novel Vector of the Rat Lungworm, Angiostrongylus cantonensis: its Introduction, Spread, and Control in China  

PubMed Central

The freshwater apple snail Pomacea canaliculata was introduced to Taiwan then to mainland China in the early 1980s from Argentina, its native region, for the purpose of aquaculture. Because of the lack of natural enemies and its tolerance of a wide range of environmental conditions, both its abundance and distribution have dramatically increased and it has become a harmful species to local agriculture and other native species in many areas of China. Unfortunately, the snail also acts as an intermediate host of Angiostrongylus cantonensis, and has been implicated in transfer of the parasite to people, resulting in angiostrongyliasis manifested as eosinophilic meningitis. Efforts to prevent its further spread and population expansion were initiated many years ago, including the use of chemicals and biological control agents to control the snail. PMID:23901377

Wu, Zhong-Dao; Lun, Zhao-Rong

2013-01-01

231

Prerequisites for parasitism in rhabditid nematodes.  

PubMed

To evaluate their potential for survival in a vertebrate host, dauer larvae from 7 species of rhabditid nematodes were subjected to in vitro conditions designed to emulate those of a vertebrate digestive tract. Dauer larvae from 3 of the 7 species, selected for their ability to survive elevated temperatures and low pH, and representing differing types of phoretic associations with invertebrate hosts, were fed to frogs to examine their ability to survive passage through a vertebrate digestive system. The degree of invasiveness of the phoretic association that dauer larvae had with their invertebrate hosts did not correspond to patterns of in vitro survivorship for any of the experimental conditions. When consumed with a prey item, dauer larvae from all 3 species were recovered from frogs 72 hr postexposure, and no differences for in vivo survivorship were observed among the 3 species. The contention that invasiveness or facultative parasitism within an invertebrate host is a beneficial or necessary step toward vertebrate parasitism by rhabditid nematodes was not supported by the survivorship data. PMID:19803545

Warburton, Elizabeth M; Zelmer, Derek A

2010-02-01

232

Nematode Locomotion in Unconfined and Confined Fluids  

E-print Network

The millimeter-long soil-dwelling nematode {\\it C. elegans} propels itself by producing undulations that propagate along its body and turns by assuming highly curved shapes. According to our recent study [PLoS ONE \\textbf{7}, e40121 (2012)] all these postures can be accurately described by a piecewise-harmonic-curvature (PHC) model. We combine this curvature-based description with highly accurate hydrodynamic bead models to evaluate the normalized velocity and turning angles for a worm swimming in an unconfined fluid and in a parallel-wall cell. We find that the worm moves twice as fast and navigates more effectively under a strong confinement, due to the large transverse-to-longitudinal resistance-coefficient ratio resulting from the wall-mediated far-field hydrodynamic coupling between body segments. We also note that the optimal swimming gait is similar to the gait observed for nematodes swimming in high-viscosity fluids. Our bead models allow us to determine the effects of confinement and finite thickness...

Bilbao, Alejandro; Vanapalli, Siva; Blawzdziewicz, Jerzy

2013-01-01

233

Evolution of Parasitism in Insect-transmitted Plant Nematodes  

PubMed Central

Nematode-insect associations have evolved many times in the phylum Nematoda, but these lineages involve plant parasitism only in the Secernentean orders Aphelenchida and Tylenchida. In the Aphelenchida (Aphelenchoidoidea), Bursaphelenchus xylophilus (Pine wood nematode), B. cocophilus (Red ring or Coconut palm nematode) (Parasitaphelenchidae), and the many potential host-specific species of Schistonchus (fig nematodes) (Aphelenchoididae) nematode-insect interactions probably evolved independently from dauer-forming, mycophagous ancestors that were phoretically transmitted to breeding sites of their insect hosts in plants. Mycophagy probably gave rise to facultative or obligate plant-parasitism because of opportunities due to insect host switches or peculiarities in host behavior. In the Tylenchida, there is one significant radiation of insect-associated plant parasites involving Fergusobia nematodes (Fergusobiinae: Neotylenchidae) and Fergusonina (Fergusoninidae) flies as mutualists that gall myrtaceous plant buds or leaves. These dicyclic nematodes have different phases that are parasitic in either the insect or the plant hosts. The evolutionary origin of this association is unclear. PMID:19265987

Giblin-Davis, R. M.; Davies, K. A.; Morris, K.; Thomas, W. K.

2003-01-01

234

Leukotriene B4 amplifies eosinophil accumulation in response to nematodes  

PubMed Central

Eosinophil accumulation is a defining feature of the immune response to parasitic worm infection. Tissue-resident cells, such as epithelial cells, are thought to initiate eosinophil recruitment. However, direct recognition of worms by eosinophils has not been explored as a mechanism for amplifying eosinophil accumulation. Here, we report that eosinophils rapidly migrate toward diverse nematode species in three-dimensional culture. These include the mammalian parasite Nippostrongylus brasiliensis and the free-living nematode Caenorhabditis elegans. Surprisingly, collective migration toward worms requires paracrine leukotriene B4 signaling between eosinophils. In contrast, neutrophils show a minimal response to nematodes, yet are able to undergo robust leukotriene-dependent migration toward IgG-coated beads. We further demonstrate that eosinophils accumulate around C. elegans in the lungs of mice. This response is not dependent on bacterial products, CCR3, or complement activation. However, mice deficient in leukotriene signaling show markedly attenuated eosinophil accumulation after injection of C. elegans or N. brasiliensis. Our findings establish that nematode-derived signals can directly induce leukotriene production by eosinophils and that leukotriene signaling is a major contributor to nematode-induced eosinophil accumulation in the lung. The similarity of the eosinophil responses to diverse nematode species suggests that conserved features of nematodes are recognized during parasite infection. PMID:24889202

Patnode, Michael L.; Bando, Jennifer K.; Krummel, Matthew F.; Locksley, Richard M.

2014-01-01

235

Resistance of Grape Rootstocks to Plant-parasitic Nematodes  

PubMed Central

Candidate grape rootstocks were selected through a rigorous screening program initiated with important sources of resistance to Meloidogyne pathotypes and to Xiphinema index in Muscadinia rotundifolia and Vitis species native to North America. Based on their rooting capability and horticultural characteristics, 200 candidates were selected from 5,000 progeny of multiple crosses between commercial grape rootstocks and wild grape species that exhibited resistance to nematodes. After a 15-year screening process, 13 selections emerged with either almost complete or complete combined resistance to M. incognita Race 3, M. incognita pathotype Harmony C, M. arenaria pathotype Harmony A, and X. index, important nematode pests of grapevines. Durability of this broad resistance was tested by challenging the selections with the target nematodes in combination and with the target nematodes in combinations with species not included in the screening process. Durability of resistance of the candidate rootstocks was also tested by exposure to the nematode communities of infested field soils from different locations. Breadth of resistance was determined on the basis of their host status to non-target nematodes, including Mesocriconema xenoplax, Pratylenchus vulnus, Tylenchulus semipenetrans and Paratylenchus hamatus. After a total of 204 separate trials, the rootstocks were released to the grape industry as UCD GRN1, UCD GRN2, UCD GRN3, UCD GRN4, and UCD GRN5. We provide a compilation of current knowledge of the host status of these five newly released rootstocks and of 27 other rootstock cultivars to plant-parasitic nematodes. PMID:23482972

Ferris, H.; Zheng, L.; Walker, M. A.

2012-01-01

236

Nematode Assemblages in Native Plant Communities of Molokai, Hawaii  

PubMed Central

Four native plant community types (in decreasing elevation: montane bog, rain forest, wet mesic forest, drier forest) on Molokai were sampled for nematodes. Six samples of 10 cores each were gathered from each community. Nematodes were extracted from 200 cm³ soil by elutriation. All extracted nematodes were counted and identified to species-level taxa. Sixty-seven species were identified among the four plant communities; only eight species occurred in all four communities. Species diversity and evenness were greater in the rain forest and mesic forest than in the bog and the drier forest, but the drier forest and mesic forest had similar species communities. The bog nematode community was not similar to the other three sites. In a presence/absence cluster analysis, all six bog sample assemblages clustered together. The rain forest samples also clustered together but were associated with the mesic forest sample closest to the rain forest edge. Of 11 nematode orders collected, Tylenchida accounted for 40% to 73% of all individuals, followed by Dorylaimida (5% to 17%). Diplogasterida were absent. No plant-parasitic nematodes of known Hawaiian agricultural importance or occurrence were collected in these native plant communities. Calculated nematode densities (76,000 to 321,300/m²) were comparable to those reported for some other Pacific tropical forests. PMID:19262867

Bernard, E. C.; Schmitt, D. P.

2005-01-01

237

Resistance of Grape Rootstocks to Plant-parasitic Nematodes.  

PubMed

Candidate grape rootstocks were selected through a rigorous screening program initiated with important sources of resistance to Meloidogyne pathotypes and to Xiphinema index in Muscadinia rotundifolia and Vitis species native to North America. Based on their rooting capability and horticultural characteristics, 200 candidates were selected from 5,000 progeny of multiple crosses between commercial grape rootstocks and wild grape species that exhibited resistance to nematodes. After a 15-year screening process, 13 selections emerged with either almost complete or complete combined resistance to M. incognita Race 3, M. incognita pathotype Harmony C, M. arenaria pathotype Harmony A, and X. index, important nematode pests of grapevines. Durability of this broad resistance was tested by challenging the selections with the target nematodes in combination and with the target nematodes in combinations with species not included in the screening process. Durability of resistance of the candidate rootstocks was also tested by exposure to the nematode communities of infested field soils from different locations. Breadth of resistance was determined on the basis of their host status to non-target nematodes, including Mesocriconema xenoplax, Pratylenchus vulnus, Tylenchulus semipenetrans and Paratylenchus hamatus. After a total of 204 separate trials, the rootstocks were released to the grape industry as UCD GRN1, UCD GRN2, UCD GRN3, UCD GRN4, and UCD GRN5. We provide a compilation of current knowledge of the host status of these five newly released rootstocks and of 27 other rootstock cultivars to plant-parasitic nematodes. PMID:23482972

Ferris, H; Zheng, L; Walker, M A

2012-12-01

238

Microsporidian Infection in a Free-Living Marine Nematode  

PubMed Central

Microsporidia are unicellular fungi that are obligate endoparasites. Although nematodes are one of the most abundant and diverse animal groups, the only confirmed report of microsporidian infection was that of the “nematode killer” (Nematocida parisii). N. parisii was isolated from a wild Caenorhabditis sp. and causes an acute and lethal intestinal infection in a lab strain of Caenorhabditis elegans. We set out to characterize a microsporidian infection in a wild nematode to determine whether the infection pattern of N. parisii in the lab is typical of microsporidian infections in nematodes. We describe a novel microsporidian species named Sporanauta perivermis (marine spore of roundworms) and characterize its infection in its natural host, the free-living marine nematode Odontophora rectangula. S. perivermis is not closely related to N. parisii and differs strikingly in all aspects of infection. Examination by transmission electron microscopy (TEM) revealed that the infection was localized in the hypodermal and muscle tissues only and did not involve the intestines. Fluorescent in situ hybridization (FISH) confirmed infection in the muscle and hypodermis, and surprisingly, it also revealed that the parasite infects O. rectangula eggs, suggesting a vertical mode of transmission. Our observations highlight the importance of studying parasites in their natural hosts and indicate that not all nematode-infecting microsporidia are “nematode killers”; instead, microsporidiosis can be more versatile and chronic in the wild. PMID:23087371

Ardila-Garcia, A. M.

2012-01-01

239

Susceptibility of the Plum Curculio, Conotrachelus nenuphar, to Entomopathogenic Nematodes  

PubMed Central

The plum curculio, Conotrachelus nenuphar, is a major pest of pome and stone fruit. Our objective was to determine virulence and reproductive potential of six commercially available nematode species in C. nenuphar larvae and adults. Nematodes tested were Heterorhabditis bacteriophora (Hb strain), H. marelatus (Point Reyes strains), H. megidis (UK211 strain), Steinernema riobrave (355 strain), S. carpocapsae (All strain), and S. feltiae (SN strain). Survival of C. nenuphar larvae treated with S. feltiae and S. riobrave, and survival of adults treated with S. carpocapsae and S. riobrave, was reduced relative to non-treated insects. Other nematode treatments were not different from the control. Conotrachelus nenuphar larvae were more susceptible to S. feltiae infection than were adults, but for other nematode species there was no significant insect-stage effect. Reproduction in C. nenuphar was greatest for H. marelatus, which produced approximately 10,000 nematodes in larvae and 5,500 in adults. Other nematodes produced approximately 1,000 to 3,700 infective juveniles per C. nenuphar with no significant differences among nematode species or insect stages. We conclude that S. carpocapsae or S. riobrave appears to have the most potential for controlling adults, whereas S. feltiae or S. riobrave appears to have the most potential for larval control. PMID:19265940

Shapiro-Ilan, David I.; Mizell, Russell F.; Campbell, James F.

2002-01-01

240

Moxidectin against ivermectin-resistant nematodes--a global view.  

PubMed

Macrocyclic lactone endectocides include two chemically distinct compounds moxidectin, a milbemycin, and ivermectin, an avermectin. The significance of the chemical differences between these compounds in relation to nematode resistance remains to be established. Reported studies indicate that moxidectin at the recommended dose rate of 0.2 mg/kg controls identified strains of nematodes, isolated from sheep and goats, with demonstrated resistance to ivermectin. This reflects the significantly greater potency of moxidectin against the 3 genera of nematodes most commonly involved in anthelmintic resistance, Haemonchus, Ostertagia and Trichostrongylus. Moxidectin, in recommended strategic treatment programmes, should reduce the risk of further development of resistance to the macrocylic lactone endectocides. PMID:8172547

Kieran, P J

1994-01-01

241

The Lance Nematode, Hoplolaimus magnistylus, on Cotton in Arkansas  

PubMed Central

The population density of Hoplolaimus magnistylus, a lance nematode, in cotton was determined at planting, mid-season, and harvest during the 1995 and 1996 growing seasons for a Poinsett County, Arkansas field. Nematode populations increased from planting to harvest in 1995 but declined in 1996. Application of aldicarb at planting at rates of 0.59 or 0.84 kg a.i./ha did not influence either nematode population density or cotton yield. This study indicates that H. magnistylus is not a serious pest of irrigated cotton in Arkansas. PMID:19274251

Robbins, R. T.; McNeely, V. M.; Lorenz, G. M.

1998-01-01

242

Biocontrol: Bacillus penetrans and Related Parasites of Nematodes.  

PubMed

Bacillus penetrans Mankau, 1975, previously described as Duboscqia penetrans Thorne 1940, is a candidate agent for biocontrol of nematodes. This review considers the life stages of this bacterium: vegetative growth phase, colony fragmentation, sporogenesis, soil phase, spore attachment, and penetration into larvae of root-knot nematodes. The morphology of the microthallus colonies and the unusual external features of the spore are discussed. Taxonomic affinities with the actinomycetes, particularly with the genus Pasteuria, are considered. Also discussed are other soil bacterial species that are potential biocontrol agents. Products of their bacterial fermentation in soil are toxic to nematodes, making them effective biocontrol agents. PMID:19300701

Sayre, R M

1980-10-01

243

Trophic interactions in soils as they affect energy and nutrient dynamics. III. Biotic interactions of bacteria, amoebae, and nematodes  

Microsoft Academic Search

Bacteria (Pseudomonas), amoebae (Acanthamoeba), and nematodes (Mesodiplogaster) were raised in soil microcosms with and without glucose additions. Nematode and amoebal grazing on bacteria significantly reduced bacterial populations by the end of a 24-day incubation period. Amoebal numbers decreased in the presence of nematodes with a corresponding increase in nematode numbers which reached a maximum of 230 nematodes\\/g of soil in

R. V. Anderson; E. T. Elliott; J. F. McClellan; D. C. Coleman; C. V. Cole; H. W. Hunt

1977-01-01

244

The Effects of Root-knot Nematode Infection and Mi-mediated Nematode Resistance in Tomato on Plant Fitness  

PubMed Central

The Mi-1.2 resistance gene in tomato (Solanum lycopersicum) confers resistance against several species of root-knot nematodes (Meloidogyne spp.). This study examined the impact of M. javanica on the reproductive fitness of near-isogenic tomato cultivars with and without Mi-1.2 under field and greenhouse conditions. Surprisingly, neither nematode inoculation or host plant resistance impacted the yield of mature fruits in field microplots (inoculum=8,000 eggs/plant), or fruit or seed production in a follow-up greenhouse bioassay conducted with a higher inoculum level (20,000 eggs/plant). However, under heavy nematode pressure (200,000 eggs/plant), greenhouse-grown plants carrying Mi-1.2 had more than ten-fold greater fruit production than susceptible plants and nearly forty-fold greater estimated lifetime seed production, confirming prior reports of the benefits of Mi-1.2. In all cases Mi-mediated resistance significantly reduced nematode reproduction. These results indicated that tomato can utilize tolerance mechanisms to compensate for moderate levels of nematode infection, but that the Mi-1.2 resistance gene confers a dramatic fitness benefit under heavy nematode pressure. No significant cost of resistance was detected in the absence of nematode infection. PMID:22791916

Corbett, Brandon P.; Jia, Lingling; Sayler, Ronald J.; Arevalo-Soliz, Lirio Milenka

2011-01-01

245

Studies on the sublittoral free-living nematodes of Liverpool Bay. II. Influence of sediment composition on the distribution of marine nematodes  

Microsoft Academic Search

Previous work has shown that the composition and diversity of nematode populations in Liverpool Bay (UK) are correlated with sediment granulometry, and possible reasons for this relationship are now discussed. Sediment granulometry and nematode size appear not to be directly related, but the range of nematode lengths is greater in the more heterogeneous sediments. Median particle diameter, sorting efficiency and

A. R. Ward; N. Wales

1975-01-01

246

GTP-Cyclohydrolase function in parasitic nematode development   

E-print Network

Parasitic nematodes of grazing livestock represent an increasing economic and welfare problem for British agriculture. By investigating specific life-cycle stages of these parasites, it may be possible to identify key ...

Baker, Rachael Helen

2012-06-30

247

EVOLUTION OF HOST SEARCH STRATEGIES IN ENTOMOPATHOGENIC NEMATODES (NEMATODA: STEINERNMATIDAE)  

Technology Transfer Automated Retrieval System (TEKTRAN)

There is interspecific variation in infective juvenile behavior within the entomopathogenic nematode genus Steinernema. This variation is consistent with use of different host searching (foraging) strategies along a continuum between ambush and cruise foraging. To address questions about the evoluti...

248

Human gastrointestinal nematode infections: are new control methods required?  

PubMed Central

Gastrointestinal (GI) nematode infections affect 50% of the human population worldwide, and cause great morbidity as well as hundreds of thousands of deaths. Despite modern medical practices, the proportion of the population infected with GI nematodes is not falling. This is due to a number of factors, the most important being the lack of good healthcare, sanitation and health education in many developing countries. A relatively new problem is the development of resistance to the small number of drugs available to treat GI nematode infections. Here we review the most important parasitic GI nematodes and the methods available to control them. In addition, we discuss the current status of new anthelmintic treatments, particularly the plant cysteine proteinases from various sources of latex-bearing plants and fruits. PMID:16965561

Stepek, Gillian; Buttle, David J; Duce, Ian R; Behnke, Jerzy M

2006-01-01

249

A uniform genetic nomenclature for the nematode Caenorhabditis elegans  

Microsoft Academic Search

A uniform system of genetic nomenclature for the nematode Caenorhabditis elegans is described. Convenient ways are specified to designate genes, mutations and strains, and to attempt to avoid name duplications.

H. Robert Horvitz; Sydney Brenner; Jonathan Hodgkin; Robert K. Herman

1979-01-01

250

Potential for Nematode Control by Mycofloras Endemic in the Tropics  

PubMed Central

Results of mycological surveys of root-knot and cyst nematodes from tropical regions indicate that most fungal species associated with females or cysts of species of Globodera, Heterodera, and Meloidogyne are those found with nematodes from temperate areas. Some fungal species, however, were found in higher frequency in tropical regions than in temperate countries; e.g., Cylindrocarpon destructans and Ulocladium atrum were the most common species associated with G. pallida and G. rostochiensis cysts in Peru. These fungi are not so frequent in nematodes from temperate areas. Fungi associated with diseased nematodes in the tropics vary greatly in nutritional requirements and include thermophilic species as well as cold-tolerant fungi. Multi-cropping systems possible in most tropical regions may be designed to increase the frequency of occurrence of microbial species antagonistic to phytonematodes. PMID:19290202

Rodríguez-Kábana, R.; Morgan-Jones, G.

1988-01-01

251

Colonization of greenhouse nematode cultures by nematophagous mites and fungi.  

PubMed

Unproductive > 7-year-old greenhouse cultures of citrus nematode (Tylenchulus semipenetrans) had a well-developed soil invertebrate fauna that included nematophagous mite species characteristic of Florida citrus groves. Nematophagous mite densities in box cultures were 285 +/- 42 mites/liter, 2.5 to 25 times higher than densities in citrus nematode-infested groves. Vigorous root-knot nematode (Meloidogyne incognita) cultures grown in steam-pasteurized soil had few nematophagous mites until more than 3 months after inoculation. Mite species diversity had a significant (P < 0.0001) positive linear relationship with culture age that explained about one-half the variance in species number. Nematophagous mite densities rose and then fell with culture age. In root-knot cultures > 3-months-old, mite densities often exceeded 1,000 mites/liter. Twelve species of nematophagous fungi also were isolated from greenhouse nematode cultures. PMID:19279841

Walter, D E; Kaplan, D T; Davis, E L

1993-12-01

252

Genetic and Pharmacological Factors That Influence Reproductive Aging in Nematodes  

E-print Network

Genetic and Pharmacological Factors That Influence Reproductive Aging in Nematodes Stacie E. Hughes reproductive aging, we analyzed genetic, environmental, and pharmacological factors that extend lifespan, Xiong C, Kornfeld K (2007) Genetic and pharmacological factors that influence reproductive aging

Kornfeld, S. Kerry

253

SCREENING OF TRANSGENIC ANTHURIUMS FOR BACTERIAL BLIGHT AND NEMATODE RESISTANCE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Anthuriums exhibit limited resistance to bacterial blight caused by Xanthomonas axonopodis pv. dieffenbachiae and to the nematodes Radopholus simile and Meloidogyne javanica. Agrobacterium tumefaciens transformation of embryogenic calli with strains LBA4404, EHA105, and AGLO resulted in transgenic p...

254

Morphological and Biological Parameters of the Knapweed Nematode, Subanguina picridis  

PubMed Central

Specimens of the knapweed nematode Subanguina picridis (Kirjanova) Brzeski obtained from different host plants were highly variable in measurement and structure. This variability refutes the validity of six Subanguina species attacking plants in the Asteraceae. PMID:19294157

Watson, A. K.

1986-01-01

255

Ecological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica  

PubMed Central

Abstract The terrestrial ecosystems of Victoria Land, Antarctica are characteristically simple in terms of biological diversity and ecological functioning. Nematodes are the most commonly encountered and abundant metazoans of Victoria Land soils, yet little is known of their diversity and distribution. Herein we present a summary of the geographic distribution, habitats and ecology of the terrestrial nematodes of Victoria Land from published and unpublished sources. All Victoria Land nematodes are endemic to Antarctica, and many are common and widely distributed at landscape scales. However, at smaller spatial scales, populations can have patchy distributions, with the presence or absence of each species strongly influenced by specific habitat requirements. As the frequency of nematode introductions to Antarctica increases, and soil habitats are altered in response to climate change, our current understanding of the environmental parameters associated with the biogeography of Antarctic nematofauna will be crucial to monitoring and possibly mitigating changes to these unique soil ecosystems. PMID:25061360

Adams, Byron J.; Wall, Diana H.; Virginia, Ross A.; Broos, Emma; Knox, Matthew A.

2014-01-01

256

Soil Organic Matter and Management of Plant-Parasitic Nematodes  

PubMed Central

Organic matter and its replenishment has become a major component of soil health management programs. Many of the soil's physical, chemical, and biological properties are a function of organic matter content and quality. Adding organic matter to soil influences diverse and important biological activities. The diversity and number of free-living and plant-parasitic nematodes are altered by rotational crops, cover crops, green manures, and other sources of organic matter. Soil management programs should include the use of the proper organic materials to improve soil chemical, physical, and biological parameters and to suppress plant-parasitic nematodes and soilborne pathogens. It is critical to monitor the effects of organic matter additions on activities of major and minor plant-parasitic nematodes in the production system. This paper presents a general review of information in the literature on the effects of crop rotation, cover crops, and green manures on nematodes and their damage to economic crops. PMID:19265946

Widmer, T. L.; Mitkowski, N. A.; Abawi, G. S.

2002-01-01

257

The draft genome of the parasitic nematode Trichinella spiralis  

PubMed Central

Genome-based studies of metazoan evolution are most informative when phylogenetically diverse species are incorporated in the analysis. As such, evolutionary trends within and outside the phylum Nematoda have been less revealing by focusing only on comparisons involving Caenorhabditis elegans. Herein, we present a draft of the 64 megabase nuclear genome of Trichinella spiralis, containing 15,808 protein coding genes. This parasitic nematode is an extant member of a clade that diverged early in the evolution of the phylum enabling identification of archetypical genes and molecular signatures exclusive to nematodes. Comparative analyses support intrachromosomal rearrangements across the phylum, disproportionate numbers of protein family deaths over births in parasitic vs. a non-parasitic nematode, and a preponderance of gene loss and gain events in nematodes relative to Drosophila melanogaster. This sequence and the panphylum characteristics identified herein will advance evolutionary studies and strategies to combat global parasites of humans, food animals and crops. PMID:21336279

Mitreva, Makedonka; Jasmer, Douglas P.; Zarlenga, Dante S.; Wang, Zhengyuan; Abubucker, Sahar; Martin, John; Taylor, Christina M.; Yin, Yong; Fulton, Lucinda; Minx, Pat; Yang, Shiaw-Pyng; Warren, Wesley C.; Fulton, Robert S.; Bhonagiri, Veena; Zhang, Xu; Hallsworth-Pepin, Kym; Clifton, Sandra W.; McCarter, James P.; Appleton, Judith; Mardis, Elaine R.; Wilson, Richard K.

2011-01-01

258

Utilization of Biological Control for Managing Plant-Parasitic Nematodes  

Microsoft Academic Search

\\u000a Biological control of plant-parasitic nematodes can be accomplished either by application of antagonistic organisms, conservation\\u000a and enhancement of indigenous antagonists, or a combination of both strategies. The application of biological control has\\u000a been inconsistent in suppressing nematode populations because the efficacy of antagonists is influenced by other soil organisms\\u000a and the host-plant. Integration of biological control with nematicides, solarization, organic

Patricia Timper

259

Nematodes from terrestrial and freshwater habitats in the Arctic.  

PubMed

WE PRESENT AN UPDATED LIST OF TERRESTRIAL AND FRESHWATER NEMATODES FROM ALL REGIONS OF THE ARCTIC, FOR WHICH RECORDS OF PROPERLY IDENTIFIED NEMATODE SPECIES ARE AVAILABLE: Svalbard, Jan Mayen, Iceland, Greenland, Nunavut, Northwest territories, Alaska, Lena River estuary, Taymyr and Severnaya Zemlya and Novaya Zemlya. The list includes 391 species belonging to 146 genera, 54 families and 10 orders of the phylum Nematoda. PMID:25197239

Holovachov, Oleksandr

2014-01-01

260

Nematodes from terrestrial and freshwater habitats in the Arctic  

PubMed Central

Abstract We present an updated list of terrestrial and freshwater nematodes from all regions of the Arctic, for which records of properly identified nematode species are available: Svalbard, Jan Mayen, Iceland, Greenland, Nunavut, Northwest territories, Alaska, Lena River estuary, Taymyr and Severnaya Zemlya and Novaya Zemlya. The list includes 391 species belonging to 146 genera, 54 families and 10 orders of the phylum Nematoda. PMID:25197239

2014-01-01

261

Dispersal and gene flow in free-living marine nematodes  

PubMed Central

Dispersal and gene flow determine connectivity among populations, and can be studied through population genetics and phylogeography. We here review the results of such a framework for free-living marine nematodes. Although field experiments have illustrated substantial dispersal in nematodes at ecological time scales, analysis of the genetic diversity illustrated the importance of priority effects, founder effects and genetic bottlenecks for population structuring between patches <1 km apart. In contrast, only little genetic structuring was observed within an estuary (<50 km), indicating that these small scale fluctuations in genetic differentiation are stabilized over deeper time scales through extensive gene flow. Interestingly, nematode species with contrasting life histories (extreme colonizers vs persisters) or with different habitat preferences (algae vs sediment) show similar, low genetic structuring. Finally, historical events have shaped the genetic pattern of marine nematodes and show that gene flow is restricted at large geographical scales. We also discuss the presence of substantial cryptic diversity in marine nematodes, and end with highlighting future important steps to further unravel nematode evolution and diversity. PMID:23356547

2013-01-01

262

Alternatives to anthelmintics for the control of nematodes in livestock.  

PubMed

Efficient and welfare-friendly livestock production demands the control of nematode infection. Current control measures rely upon anthelmintic treatment but are threatened by the widespread evolution of drug-resistance in parasite populations. Several methods have been advocated to control nematodes without relying on effective anthelmintics. These include grazing management, biological control, nutritional supplementation, vaccination, and genetic approaches. Each method has its advantages and disadvantages. There are several grazing management schemes that can reduce the severity of infection but they are insufficient on their own to control infection. Biological control includes the use of predatory fungi to control nematode populations and the use of pasture species that can reduce the intensity of infection. Fungi can control nematodes but the current requirement for daily feeding means that this approach will be most useful for animals that are handled daily. Feeding supplementary protein can control nematode infection. The method is simple but can be expensive and may not be cost-effective for some marginal enterprises. Genetic approaches include the use of resistant breeds and selective breeding. Some breeds will thrive in conditions that kill animals from other breeds but substitution of resistant breeds is not always feasible. Selective breeding is effective and inexpensive but requires a high level of expertise. The most appropriate method or set of methods to minimize the adverse consequences of nematode infection may vary among farms. PMID:17076922

Stear, M J; Doligalska, M; Donskow-Schmelter, K

2007-02-01

263

First report of the nematode Leidynema appendiculata from Periplaneta fuliginosa.  

PubMed

The smokybrown cockroach Periplaneta fuliginosa has spread all over the world, and is now one of the most undesired invasive alien pests in Japan. Because cockroaches are generally infected by thelastomatid nematodes, they are being distributed around the world with their parasitic nematodes. Nothing is known about parasitic nematode species in P. fuliginosa differences, or similarity of the parasite's population structures between the different countries of the host cockroaches. Here we investigated the P. fuliginosa invasive to Japan and found that 100% of individuals were infected with one nematode species. According to the morphology and the sequence of the D2/D3 expansion segment of the 28S ribosomal RNA gene, we identified the parasite as Leidynema appendiculata. This nematode reproduced by haplodiploidy and its developmental timing under various conditions is quite divergent. Their population in the hindgut of P. fuliginosa was controlled with a few adult females and a male. This is the first report of the thelastomatid nematode isolated from the smokybrown cockroach, and is the basis for our future research examining the origin, distribution route and immigration history of the cockroach and the impact of L. appendiculata on native Japanese cockroach species. PMID:24827090

Ozawa, Sota; Vicente, Cláudia S L; Sato, Kazuki; Yoshiga, Toyoshi; Kanzaki, Natsumi; Hasegawa, Koichi

2014-06-01

264

Nematode Communities in Organically and Conventionally Managed Agricultural Soils  

PubMed Central

Interpretation of nematode community indices requires a reference to a relatively undisturbed community. Maturity and trophic diversity index values were compared for five pairs of certified organically and conventionally managed soils in the Piedmont region of North Carolina. Available nitrogen (nitrate, ammonium) was estimated at various lag periods relative to times of sampling for nematode communities to determine the strength of correlative relationship between nematode communities and nitrogen availability. Soils were sampled six times yearly in 1993 and 1994 to determine the best time of year to sample. Maturity values for plant parasites were greater in organically than conventionally managed soils, and differences between management systems were greater in fall than spring months. However, other maturity and diversity indices did not differ between the two management practices. Differences in crop species grown in the two systems accounted for most differences observed in the community of plant-parasitic nematodes. Indices of free-living nematodes were correlated negatively with concentrations of ammonium, whereas indices of plant-parasitic nematodes were correlated positively with concentrations of nitrate. Due to the similarity of index values between the two systems, organically managed soils are not suitable reference sites for monitoring and assessing the biological aspects of soil quality for annually harvested crops. PMID:19270884

Neher, Deborah A.

1999-01-01

265

Diverse Host-Seeking Behaviors of Skin-Penetrating Nematodes  

PubMed Central

Skin-penetrating parasitic nematodes infect approximately one billion people worldwide and are responsible for some of the most common neglected tropical diseases. The infective larvae of skin-penetrating nematodes are thought to search for hosts using sensory cues, yet their host-seeking behavior is poorly understood. We conducted an in-depth analysis of host seeking in the skin-penetrating human parasite Strongyloides stercoralis, and compared its behavior to that of other parasitic nematodes. We found that Str. stercoralis is highly mobile relative to other parasitic nematodes and uses a cruising strategy for finding hosts. Str. stercoralis shows robust attraction to a diverse array of human skin and sweat odorants, most of which are known mosquito attractants. Olfactory preferences of Str. stercoralis vary across life stages, suggesting a mechanism by which host seeking is limited to infective larvae. A comparison of odor-driven behavior in Str. stercoralis and six other nematode species revealed that parasite olfactory preferences reflect host specificity rather than phylogeny, suggesting an important role for olfaction in host selection. Our results may enable the development of new strategies for combating harmful nematode infections. PMID:25121736

Castelletto, Michelle L.; Gang, Spencer S.; Okubo, Ryo P.; Tselikova, Anastassia A.; Nolan, Thomas J.; Platzer, Edward G.; Lok, James B.; Hallem, Elissa A.

2014-01-01

266

Low cryoprotectant concentrations and fast cooling for nematode cryostorage.  

PubMed

Cryopreservation protocols based on slow freezing or vitrification often result in cell injury due to ice formation, cell dehydration and/or toxic concentrations of cryoprotectant (CPA). In this study, we present a cryopreservation technique based on low, non-toxic concentrations of cryoprotectants (? 2-4M) combined with a rapid cooling rate in the liquid nitrogen phase (-196°C). Protocols for successfully cryopreserving the plant parasitic nematodes Globodera tabacum tabacum, Heterodera schachtii and Meloidogyne incognita were developed, as demonstrated by the high survival rates and reproducibility of cyst and root-knot nematode species post-cryostorage. This approach for effective cryopreservation of viable plant-parasitic nematodes was developed by inducing an "apparent vitrification" by rapid cooling of the microscopic samples in less than 2M of cryoprotectant. The extremely thin structure (15-20 ?m width, 350-400 ?m length) of these nematodes, in combination with a direct and rapid exposure to LN(2), likely prevents the formation of damaging ice crystals. Moreover, this procedure results in viability of both short- and long-cryostorage samples. These techniques could potentially be used for the near-indefinite preservation of thousands of different nematode species. A cryo-nematode collection produced in our lab is available and presented here. PMID:21524646

Irdani, Tiziana; Scotto, Cristina; Roversi, Pio Federico

2011-08-01

267

Incidence and influence of plant-parasitic nematodes in southern Illinois peach orchards  

Technology Transfer Automated Retrieval System (TEKTRAN)

The frequency, distribution and impact of plant-parasitic nematodes in southern Illinois peach orchards were determined. Nine plant parasitic nematode genera were detected comprising 11 different species: Helicotylenchus platyurus, Helicotylenchus pseudorobustus, Hoplolaimus spp., Meloidogyne spp., ...

268

SURVEY OF STYLET BEARING NEMATODES ASSOCIATED WITH DATE PALM IN KHUZDAR DISTRICT, BALOCHISTAN, PAKISTAN  

Technology Transfer Automated Retrieval System (TEKTRAN)

Surveys were conducted during September and October 2002 to identify the stylet-bearing nematodes associated with date palm in Khuzdar district, Balochistan, Pakistan. The nematodes recorded were Tylenchus sp., Merlinius sp., Helicotylenchus indicus, Psilenchus hilarulus, Aphelenchoides sp., Meloido...

269

Travelling through time and space on wings of beetles: A tripartite insect-fungi-nematode association  

Microsoft Academic Search

Here we report a previously undescribed symbiotic association involving spruce beetles, Dendroctonus rufipennis Kirby, several species of fungi, and a nematode, Ektaphelenchus obtusus Massey. The nematodes and fungi occur within special pocket-like structures, hereafter termed \\

Yasmin J. Cardoza; Susan Paskewitz; Kenneth F. Raffa

2006-01-01

270

Susceptibility of the lesser peachtree borer (Lepidoptera: Sesiidae) to entomopathogenic nematodes under laboratory conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

The lesser peachtree borer, Synanthedon pictipes is an important pest of Prunus spp. We determined the susceptibility of S. pictipes to six entomopathogenic nematode species: Heterorhabditis bacteriophora, H. indica, H. marelatus, Steinernema carpocapsae, S. feltiae, and S. riobrave. Nematode viru...

271

[Intestinal nematodes of the Aythyini ducks in Western Pomerania].  

PubMed

Intestinal nematodes of the Aythyini ducks in Western Pomerania. Biology, including ecology, of the Aythyini renders them particularly attractive subjects of parasitological studies. The tribe is represented in Poland by 4 nesting species; two of them, Aythya fuligula and A. ferina, are very abundant game birds. However, their helminth fauna, including nematodes, is still very poorly known. This study was aimed at quantifying the structure of parasitic intestinal nematodes of the Western Pomeranian Aythyini. The study, performed in 1999-2004, involved a total of 71 ducks representing 3 species: A. ferina, A. fuligula, and A. marila. The nematodes, isolated from the intestines, were fixed in 75% ethyl alcohol and cleared in lactic acid. Among the 9668 helminth individuals found, 589 (6.1%) represented the phylum Nematoda. They were found in 57 ducks (80.3% of all the ducks examined). The nematodes belonged to the following 4 families: Amidostomatidae, Tetrameridae, Acuariidae, and Trichuridae. They were identified as representing 8 species, 2 genera (Amidostomoides sp. and Tetrameres sp.), and 1 subfamily (Capillariinae gen. sp.); in addition, 1 damaged individual could be identified as a nematode only. The highest prevalence (57.8%), at mean intensity (4.8 inds), was typical of Amidostomoides petrovi (Shakhtahtinskaya, 1956) Lomakin, 1991, while Tetrameres fissispina (Diesing, 1861) Travassos, 1914 occurred with the highest intensity (15.1 inds) and 12.7% prevalence. Nematodes of the subfamily Capillariinae occurred with a fairly high intensity (averaging 10.0 inds) as well, although their prevalence was not high, either (4.2% of all ducks were infected). The nematofauna studied was clearly dominated by A. petrovi, T. fissispina, and Capillaria anatis (Schrank, 1790). The total frequency of occurrence of those species was close to 80%; their dominance indices exceeded the threshold value of 0.1 and amounted to 1.6 (the dominant A. petrovi), 0.2, and 0.5 (the subdominants T. fissispina and C. anatis, respectively). The three species listed occurred with the highest mean density (2.8; 1.9; and 1.8 nematode per duck examined). No age- (adult vs. immature) or sex- (males vs. females) related differences in the quantitative structure of the parasitic Aythyini nematodes were observed. PMID:16838626

Kavetska, Katarzyna M

2005-01-01

272

The dual effects of root-cap exudates on nematodes: from quiescence in plant-parasitic nematodes to frenzy in entomopathogenic nematodes  

PubMed Central

To defend themselves against herbivores and pathogens, plants produce numerous secondary metabolites, either constitutively or de novo in response to attacks. An intriguing constitutive example is the exudate produced by certain root-cap cells that can induce a state of reversible quiescence in plant-parasitic nematodes, thereby providing protection against these antagonists. The effect of such root exudates on beneficial entomopathogenic nematodes (EPNs) remains unclear, but could potentially impair their use in pest management programmes. We therefore tested how the exudates secreted by green pea (Pisum sativum) root caps affect four commercial EPN species. The exudates induced reversible quiescence in all EPN species tested. Quiescence levels varied with the green pea cultivars tested. Notably, after storage in root exudate, EPN performance traits were maintained over time, whereas performances of EPNs stored in water rapidly declined. In sharp contrast to high concentrations, lower concentrations of the exudate resulted in a significant increase in EPN activity and infectiousness, but still reduced the activity of two plant-parasitic nematode species. Our study suggests a finely tuned dual bioactivity of the exudate from green pea root caps. Appropriately formulated, it can favour long-term storage of EPNs and boost their infectiousness, while it may also be used to protect plants from plant-parasitic nematodes. PMID:25165149

Hiltpold, Ivan; Jaffuel, Geoffrey; Turlings, Ted C. J.

2015-01-01

273

The dual effects of root-cap exudates on nematodes: from quiescence in plant-parasitic nematodes to frenzy in entomopathogenic nematodes.  

PubMed

To defend themselves against herbivores and pathogens, plants produce numerous secondary metabolites, either constitutively or de novo in response to attacks. An intriguing constitutive example is the exudate produced by certain root-cap cells that can induce a state of reversible quiescence in plant-parasitic nematodes, thereby providing protection against these antagonists. The effect of such root exudates on beneficial entomopathogenic nematodes (EPNs) remains unclear, but could potentially impair their use in pest management programmes. We therefore tested how the exudates secreted by green pea (Pisum sativum) root caps affect four commercial EPN species. The exudates induced reversible quiescence in all EPN species tested. Quiescence levels varied with the green pea cultivars tested. Notably, after storage in root exudate, EPN performance traits were maintained over time, whereas performances of EPNs stored in water rapidly declined. In sharp contrast to high concentrations, lower concentrations of the exudate resulted in a significant increase in EPN activity and infectiousness, but still reduced the activity of two plant-parasitic nematode species. Our study suggests a finely tuned dual bioactivity of the exudate from green pea root caps. Appropriately formulated, it can favour long-term storage of EPNs and boost their infectiousness, while it may also be used to protect plants from plant-parasitic nematodes. PMID:25165149

Hiltpold, Ivan; Jaffuel, Geoffrey; Turlings, Ted C J

2015-02-01

274

In vitro proteolysis of nematode FLPs by preparations from the free-living nematode Panagrellus redivivus and two plant-parasitic nematodes (Heterodera glycines and Meloidogyne incognita)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Proteolytic activities in extracts from three nematodes, the plant parasites Heterodera glycines and Meloidogyne incognita, and the free-living Panagrellus redivivus, were surveyed for substrate preferences using a battery of seven FRET-modified peptide substrates, all derived from members of the la...

275

Nematodes as indicators of soil recovery in tailings of a lead\\/zinc mine  

Microsoft Academic Search

Trophic groups and functional guilds of soil nematodes were measured under four mine tailing subsystems in the Baoshan lead\\/zinc mine, Hunan Province, southern China to test the indicator value of nematodes for heavy metal pollution. No obvious correlation was found between heavy metal concentration and the total number of nematodes. However, the densities of c–p3, c–p4 and c–p5 nematodes were

Yuanhu Shao; Weixin Zhang; Juecui Shen; Lixia Zhou; Hanping Xia; Wensheng Shu; Howard Ferris; Shenglei Fu

2008-01-01

276

Coprinus comatus: A basidiomycete fungus forms novel spiny structures and infects nematode  

Microsoft Academic Search

Nematophagous basidiomycete fungi kill nematodes by trapping, endoparasitizing and pro- ducing toxin. In our studies Coprinus comatus (O.F.Mull. : Fr.) Pers. is found to be a nematode-de- stroying fungus; this fungus immobilizes, kills and uses free-living nematode Panagrellus redivivus Good- ey and root-knot nematode Meloidogyne arenaria Neal. C. comatus produces an unusual structure des- ignated spiny ball. Set on a

Hong Luo; Minghe Mo; Xiaowei Huang; Xuan Li

277

Dissecting host plant manipulation by cyst and root-knot nematodes  

Microsoft Academic Search

Cyst ( Globodera spp. and Heterodera spp.) and root-knot nematodes ( Meloidogyne spp.), one of the most damaging crop pests, are a perfect example of highly adapted, sophisticated root parasites. <\\/span>These nematodes induces specialized feeding structures (cyst nematodes-syncytia, root-knot nematode-giant cells) within the host root and benefits from guaranteed continues supply of food and water from their host plant and

A. Karczmarek

2006-01-01

278

Signatures of adaptation to plant parasitism in nematode genomes.  

PubMed

SUMMARY Plant-parasitic nematodes cause considerable damage to global agriculture. The ability to parasitize plants is a derived character that appears to have independently emerged several times in the phylum Nematoda. Morphological convergence to feeding style has been observed, but whether this is emergent from molecular convergence is less obvious. To address this, we assess whether genomic signatures can be associated with plant parasitism by nematodes. In this review, we report genomic features and characteristics that appear to be common in plant-parasitic nematodes while absent or rare in animal parasites, predators or free-living species. Candidate horizontal acquisitions of parasitism genes have systematically been found in all plant-parasitic species investigated at the sequence level. Presence of peptides that mimic plant hormones also appears to be a trait of plant-parasitic species. Annotations of the few genomes of plant-parasitic nematodes available to date have revealed a set of apparently species-specific genes on every occasion. Effector genes, important for parasitism are frequently found among those species-specific genes, indicating poor overlap. Overall, nematodes appear to have developed convergent genomic solutions to adapt to plant parasitism. PMID:25656361

Bird, David McK; Jones, John T; Opperman, Charles H; Kikuchi, Taisei; Danchin, Etienne G J

2015-02-01

279

A Bioassay to Estimate Root Penetration by Nematodes  

PubMed Central

An in vitro bioassay with a 96-well microtiter plate was used to study the effect of lectins on burrowing nematode penetration of citrus roots. In each well, one 4-mm root segment, excised from the zone of elongation of rough lemon roots, was buried in 0.88 g dry sand. Addition of a Radopholus citrophilus suspension containing ca. 300 nematodes in 50 ?1 test solution completely moistened the sand in each well. The technique assured uniform treatment concentration throughout the medium. Within 16-24 hours, burrowing nematodes penetrated citrus root pieces, primarily through the cut ends. The lectins (100 ?g/ml) Concanavalin A (Con A), soybean agglutinin (SBA), wheat germ agglutinin (WGA), and Lotus tetragonolobus agglutinin (LOT) stimulated an increase in penetration of citrus root segments by Radopholus citrophilus. Concentrations as low as 12.5 ?g/ml Con A, LOT, and WGA stimulated burrowing nematode penetration of citrus roots. Heat denaturation of the lectins reversed their effect on penetration; however, incubation of nematodes in lectin (25 ?g/ml) with 25 mM competitive sugars did not. The reason for enhanced penetration associated with lectins is unclear. PMID:19283153

Kaplan, David T.; Davis, Eric L.

1991-01-01

280

Organic and Inorganic Nitrogen Amendments to Soil as Nematode Suppressants  

PubMed Central

Inorganic fertilizers containing ammoniacal nitrogen or formulations releasing this form of N in the soil are most effective for suppressing nematode populations. Anhydrous ammonia has been shown to reduce soil populations of Tylenchorhynchus claytoni, Helicotylenchus dihystera, and Heterodera glycines. The rates required to obtain significant suppression of nematode populations are generally in excess of 150 kg N/ha. Urea also suppresses several nematode species, including Meloidogyne spp., when applied at rates above 300 kg N/ha. Additional available carbon must be provided with urea to permit soil microorganisms to metabolize excess N and avoid phytotoxic effects. There is a direct relation between the amount of "protein" N in organic amendments and their effectiveness as nematode population suppressants. Most nematicidal amendments are oil cakes, or animal excrements containing 2-7% (w:w) N; these materials are effective at rates of 4-10 t/ha. Organic soil amendments containing mucopolysaccharides (e.g., mycelial wastes, chitinous matter) are also effective nematode suppressants. PMID:19294153

Rodríguez-Kábana, R.

1986-01-01

281

Plant genes involved in harbouring symbiotic rhizobia or pathogenic nematodes.  

PubMed

The establishment and development of plant-microorganism interactions involve impressive transcriptomic reprogramming of target plant genes. The symbiont (Sinorhizobium meliloti) and the root knot-nematode pathogen (Meloidogyne incognita) induce the formation of new root organs, the nodule and the gall, respectively. Using laser-assisted microdissection, we specifically monitored, at the cell level, Medicago gene expression in nodule zone II cells, which are preparing to receive rhizobia, and in gall giant and surrounding cells, which play an essential role in nematode feeding and constitute the typical root swollen structure, respectively. We revealed an important reprogramming of hormone pathways and C1 metabolism in both interactions, which may play key roles in nodule and gall neoformation, rhizobia endocytosis and nematode feeding. Common functions targeted by rhizobia and nematodes were mainly down-regulated, whereas the specificity of the interaction appeared to involve up-regulated genes. Our transcriptomic results provide powerful datasets to unravel the mechanisms involved in the accommodation of rhizobia and root-knot nematodes. Moreover, they raise the question of host specificity and the evolution of plant infection mechanisms by a symbiont and a pathogen. PMID:22360638

Damiani, Isabelle; Baldacci-Cresp, Fabien; Hopkins, Julie; Andrio, Emilie; Balzergue, Sandrine; Lecomte, Philippe; Puppo, Alain; Abad, Pierre; Favery, Bruno; Hérouart, Didier

2012-04-01

282

Efficacy of Methionine Against Ectoparasitic Nematodes on Golf Course Turf  

PubMed Central

Plant-parasitic nematodes are important pathogens of intensely-managed turf used on golf courses. Two of these nematodes that are common in the southeastern US are Belonolaimus longicaudatus and Mesocriconema ornata. Currently, there is a lack of effective treatments that can be used to manage these important pests. Turfgrass field trials evaluated DL-methionine as a turfgrass nematicide against B. longicaudatus and M. ornata. One trial was on a bermudagrass putting green, the other was on zoysiagrass maintained under putting-green conditions. Two rates of methionine, 1120 kg/ha in a single application, and 112 kg/ha applied twice four weeks apart, were compared with untreated control and fenamiphos treatments. Measurements collected included soil nematode counts, turf density, and root lengths. In both trials, 1120 kg/ha of methionine reduced numbers of both nematode species (P ? 0.1), and 112 kg/ha of methionine reduced numbers of both nematode species after two applications. Bermudagrass turf density responded favorably to both methionine rates and root lengths were improved by the 1120 kg/ha rate. Zoysiagrass showed short-term phytotoxicity to methionine, but quickly recovered and treated plots were improved compared to the untreated controls by the end of the trial. These trials indicated that methionine has potential for development as a turfgrass nematicide, but further research is needed to determine how it can best be used. PMID:22736817

Cuda, James P.; Stevens, Bruce R.

2009-01-01

283

A novel flavivirus in the soybean cyst nematode.  

PubMed

Heterodera glycines, the soybean cyst nematode (SCN), is a subterranean root pathogen that causes the most damaging disease of soybean in the USA. A novel nematode virus genome, soybean cyst nematode virus 5 (SbCNV-5), was identified in RNA sequencing data from SCN eggs and second-stage juveniles. The SbCNV-5 RNA-dependent RNA polymerase and RNA helicase domains had homology to pestiviruses in the family Flaviviridae, suggesting that SbCNV-5 is a positive-polarity ssRNA virus. SbCNV-5 RNA was present in all nematode developmental stages, indicating a transovarial mode of transmission, but is also potentially sexually transmitted via the male. SbCNV-5 was common in SCN laboratory cultures and in nematode populations isolated from the field. Transmission electron microscopy of sections from a female SCN showed virus particles budding from the endoplasmic reticulum and in endosomes. The size of the viral genome was 19?191 nt, which makes it much larger than other known pestiviruses. Additionally, the presence of a methyltransferase in the SbCNV-5 genome is atypical for a pestivirus. When cDNA sequences were mapped to the genome of SbCNV-5, a disproportionate number aligned to the 3' NTR, suggesting that SbCNV-5 produces a subgenomic RNA, which was confirmed by RNA blot analysis. As subgenomic RNAs and methyltransferases do not occur in pestiviruses, we conclude that SbCNV-5 is a new flavivirus infecting SCNs. PMID:24643877

Bekal, Sadia; Domier, Leslie L; Gonfa, Biruk; McCoppin, Nancy K; Lambert, Kris N; Bhalerao, Kaustubh

2014-06-01

284

The FMRFamide-Like Peptide Family in Nematodes.  

PubMed

In the three decades since the FMRFamide peptide was isolated from the mollusk Macrocallista nimbosa, structurally similar peptides sharing a C-terminal RFamide motif have been identified across the animal kingdom. FMRFamide-like peptides (FLPs) represent the largest known family of neuropeptides in invertebrates. In the phylum Nematoda, at least 32 flp-genes are classified, making the FLP system of nematodes unusually complex. The diversity of the nematode FLP complement is most extensively mapped in Caenorhabditis elegans, where over 70 FLPs have been predicted. FLPs have shown to be expressed in the majority of the 302 C. elegans neurons including interneurons, sensory neurons, and motor neurons. The vast expression of FLPs is reflected in the broad functional repertoire of nematode FLP signaling, including neuroendocrine and neuromodulatory effects on locomotory activity, reproduction, feeding, and behavior. In contrast to the many identified nematode FLPs, only few peptides have been assigned a receptor and there is the need to clarify the pathway components and working mechanisms of the FLP signaling network. Here, we review the diversity, distribution, and functions of FLPs in nematodes. PMID:24982652

Peymen, Katleen; Watteyne, Jan; Frooninckx, Lotte; Schoofs, Liliane; Beets, Isabel

2014-01-01

285

Enzymology of the nematode cuticle: A potential drug target?  

PubMed Central

All nematodes possess an external structure known as the cuticle, which is crucial for their development and survival. This structure is composed primarily of collagen, which is secreted from the underlying hypodermal cells. Extensive studies using the free-living nematode Caenorhabditis elegans demonstrate that formation of the cuticle requires the activity of an extensive range of enzymes. Enzymes are required both pre-secretion, for synthesis of component proteins such as collagen, and post-secretion, for removal of the previous developmental stage cuticle, in a process known as moulting or exsheathment. The excretion/secretion products of numerous parasitic nematodes contain metallo-, serine and cysteine proteases, and these proteases are conserved across the nematode phylum and many are involved in the moulting/exsheathment process. This review highlights the enzymes required for cuticle formation, with a focus on the post-secretion moulting events. Where orthologues of the C. elegans enzymes have been identified in parasitic nematodes these may represent novel candidate targets for future drug/vaccine development. PMID:25057463

Page, Antony P.; Stepek, Gillian; Winter, Alan D.; Pertab, David

2014-01-01

286

The FMRFamide-Like Peptide Family in Nematodes  

PubMed Central

In the three decades since the FMRFamide peptide was isolated from the mollusk Macrocallista nimbosa, structurally similar peptides sharing a C-terminal RFamide motif have been identified across the animal kingdom. FMRFamide-like peptides (FLPs) represent the largest known family of neuropeptides in invertebrates. In the phylum Nematoda, at least 32 flp-genes are classified, making the FLP system of nematodes unusually complex. The diversity of the nematode FLP complement is most extensively mapped in Caenorhabditis elegans, where over 70 FLPs have been predicted. FLPs have shown to be expressed in the majority of the 302 C. elegans neurons including interneurons, sensory neurons, and motor neurons. The vast expression of FLPs is reflected in the broad functional repertoire of nematode FLP signaling, including neuroendocrine and neuromodulatory effects on locomotory activity, reproduction, feeding, and behavior. In contrast to the many identified nematode FLPs, only few peptides have been assigned a receptor and there is the need to clarify the pathway components and working mechanisms of the FLP signaling network. Here, we review the diversity, distribution, and functions of FLPs in nematodes. PMID:24982652

Peymen, Katleen; Watteyne, Jan; Frooninckx, Lotte; Schoofs, Liliane; Beets, Isabel

2014-01-01

287

Variation in the susceptibility of Drosophila to different entomopathogenic nematodes.  

PubMed

Entomopathogenic nematodes (EPNs) in the genera Heterorhabditis and Steinernema are lethal parasites of insects that are of interest as models for understanding parasite-host interactions and as biocontrol agents for insect pests. EPNs harbor a bacterial endosymbiont in their gut that assists in insect killing. EPNs are capable of infecting and killing a wide range of insects, yet how the nematodes and their bacterial endosymbionts interact with the insect immune system is poorly understood. Here, we develop a versatile model system for understanding the insect immune response to parasitic nematode infection that consists of seven species of EPNs as model parasites and five species of Drosophila fruit flies as model hosts. We show that the EPN Steinernema carpocapsae, which is widely used for insect control, is capable of infecting and killing D. melanogaster larvae. S. carpocapsae is associated with the bacterium Xenorhabdus nematophila, and we show that X. nematophila induces expression of a subset of antimicrobial peptide genes and suppresses the melanization response to the nematode. We further show that EPNs vary in their virulence toward D. melanogaster and that Drosophila species vary in their susceptibilities to EPN infection. Differences in virulence among different EPN-host combinations result from differences in both rates of infection and rates of postinfection survival. Our results establish a powerful model system for understanding mechanisms of host-parasite interactions and the insect immune response to parasitic nematode infection. PMID:25561714

Peña, Jennifer M; Carrillo, Mayra A; Hallem, Elissa A

2015-03-01

288

RNA interference in nematodes and the chance that favored Sydney Brenner.  

PubMed

The efficiency of RNA interference varies between different organisms, even among nematodes. A recent report of successful RNA interference in the nematode Panagrolaimus superbus in BMC Molecular Biology has implications for the comparative study of the functional genomics of nematode species, and prompts reflections on the choice of Caenorhabditis elegans as a model organism. PMID:19014674

Félix, Marie-Anne

2008-01-01

289

78 FR 27856 - Golden Nematode; Removal of Regulated Areas in Livingston and Steuben Counties, NY  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. APHIS-2012-0079] Golden Nematode; Removal of Regulated Areas in Livingston...interim rule that amended the golden nematode regulations by removing areas in Livingston...these two counties are free of golden nematode, and we determined that regulation...

2013-05-13

290

Fungal-feeding habits of six nematode isolates in the genus Filenchus  

Microsoft Academic Search

The family Tylenchidae is a large group of soil nematodes but their feeding habits are not fully known. We studied the fungal-feeding abilities of nematodes in the genus Filenchus. We measured population growth rates (PGRs) of six nematode isolates, representing three Filenchus species, when feeding on seven fungal species on two types of culture media. On Potato Dextrose Agar (PDA)

Hiroaki Okada; Hiroki Harada; Ikuo Kadota

2005-01-01

291

Impact of the nematophagous fungus Pochonia chlamydosporia on nematode and microbial populations  

Microsoft Academic Search

Results: The soil contained 28 different nematode taxa equally distributed amongst the three trophic groups. Total myco\\/bacteriophagous (BPN) and predatory nematodes (PN) counts showed no obvious trends related to differences in plant species or to the application of P. chlamydosporia or M. incognita (Fig. 1). Total plant parasitic nematodes (PPN), however, increased in both the presence of the host plants,

Qudsia Tahseen; Ian M. Clark; Simon D. Atkins; Brian R. Kerry; Penny R. Hirsch

292

Susceptibility of the boll weevil to Steinernema riobrave and other entomopathogenic nematodes  

Microsoft Academic Search

The susceptibility of the boll weevil (BW), Anthonomus grandis Boheman, to Steinernema riobrave and other nematode species in petri dishes, soil (Hidalgo sandy clay loam), and cotton bolls and squares was investigated. Third instar weevils were susceptible to entomopathogenic nematode (EN) species and strains in petri dish bioassays at 30°C. Lower LC50’s occurred with S. riobrave TX- 355 (2 nematodes

H Enrique Cabanillas

2003-01-01

293

A Treadmill to Localize, Exercise, and Measure the Propulsive Power of Nematodes  

NASA Astrophysics Data System (ADS)

The nematodes C. elegans is often used as model biological system to study the genetic basis of behavior, disease-progression, and aging, as well as to develop new therapies and screen drugs. On occasion, it is desirable to quantify the nematode's muscle power. Here, we present a kind of nematode treadmill. The device consists of a tapered conduit filled with aqueous solution. The conduit is subjected to a DC electric field and to pressure-driven flow directed from the narrow end. The nematode is inserted at the conduit's wide end. Directed by the electric field (through electrotaxis), the nematode swims deliberately upstream toward the negative pole. As the conduit narrows, the average fluid velocity and the drag force on the nematode increase. Eventually, the nematode arrives at an equilibrium position, at which its propulsive power balances the viscous drag force. The nematode's propulsive power is estimated with direct numerical simulations of the flow field around the nematode. The calculations utilize the experimentally imaged gait as a boundary condition. The device is useful to retain the nematode at a nearly fixed position for prolonged observations under a microscope, to keep the nematode exercising, and to estimate the nematode's power based on the conduit's width at the equilibrium position.

Yuan, Jinzhou; Chuan, Han-Sheng; Gnatt, Michael; Raizen, David; Bau, Haim

2011-11-01

294

Development of a PCR-based Molecular Marker to Select for Nematode Resistance in Peanut  

Technology Transfer Automated Retrieval System (TEKTRAN)

The peanut root-knot nematode (Meloidogyne arenaria (Neal) Chitwood race 1) is a significant pathogen on peanut (Arachis hypogaea L.). Nematode-resistant cultivars would reduce yield losses while reducing the use of nematicides in fields where these nematodes occur. Through years of breeding effor...

295

Prevalence of Pasteuria SP. on Renfirom Nematode in a Georgia Cotton Field  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pasteuria species are bacterial parasites of nematodes and have been associated with suppression of root-knot, sting, and cyst nematode populations. Little is known about the Pasteuria sp. infecting the reniform nematode. While sampling a cotton field study near Cochran, GA, we found Pasteuria spo...

296

Navigation and chemotaxis of nematodes in bulk and confined fluids  

NASA Astrophysics Data System (ADS)

Small nematodes, such as the model organism C. elegans, propel themselves by producing sinuous undulations along the body and perform turns by varying the undulation amplitude. We have recently demonstrated [PLoS ONE 7(7) e40121 (2012)] that such motions can be accurately represented in terms of a piecewise-harmonic body curvature. We combine our harmonic-curvature description with highly accurate hydrodynamic bead-chain models to investigate the swimming efficiency and turning capabilities of the worm in bulk and confined fluids. Our results indicate that for the same change of the curvature-wave amplitude, a swimming nematode turns by a smaller angle compared to a crawling worm. The difference is due to rotational slip with respect to the surrounding medium, but the angles are sufficiently large to allow for efficient turning maneuvers. We use our description of nematode maneuverability to study chemotaxis in both confined and unconfined fluids.

Bilbao, Alejandro; Padmanabhan, Venkat; Rumbaugh, Kendra; Vanapalli, Siva; Blawzdziewicz, Jerzy

2013-03-01

297

Natural Occurrence of Entomogenous Nematodes in Tennessee Nursery Soils  

PubMed Central

To isolate potential insect biocontrol agents, entomogenous nematodes were surveyed in Tennessee plant nurseries in 1991. Soil samples from 113 nursery sites were baited with greater wax moth (Galleria mellonella) larvae, house cricket (Acheta domesticus) adults, lesser mealworm (Alphitobius diaperings) adults, and house fly (Musca domestica) larvae. Heterorhabditis bacteriophora and Steinernema carpocapsae were each recovered from 17 soil samples. Heterorhabditis bacteriophora was more common in habitats with crape myrtle (Lagerstroemia indica) and Chinese juniper (Juniperus chinensis) than other nursery plants, and S. carpocapsae was more frequently recovered from habitats with juniper and Southern magnolia (Magnolia grandiflora). Bulk density, electrical conductivity, organic matter, pH, temperature, and moisture content of the entomogenous-nematode positive soil samples were compared. Other nematode genera recovered with insect baits included Rhabditis sp., Pelodera sp., Cryptaphelenchoides sp., and Mesodiplogaster sp., which was recovered from a greater percentage of soil samples than the other five genera. PMID:19279756

Rueda, L. M.; Osawaru, S. O.; Georgi, L. L.; Harrison, R. E.

1993-01-01

298

Nematicidal Bacteria Associated to Pinewood Nematode Produce Extracellular Proteases  

PubMed Central

Bacteria associated with the nematode Bursaphelenchus xylophilus, a pathogen of trees and the causal agent of pine wilt disease (PWD) may play a role in the disease. In order to evaluate their role (positive or negative to the tree), strains isolated from the track of nematodes from infected Pinus pinaster trees were screened, in vitro, for their nematicidal potential. The bacterial products, from strains more active in killing nematodes, were screened in order to identify and characterize the nematicidal agent. Forty-seven strains were tested and, of these, 21 strains showed capacity to produce extracellular products with nematicidal activity. All Burkholderia strains were non-toxic. In contrast, all Serratia strains except one exhibited high toxicity. Nematodes incubated with Serratia strains showed, by SEM observation, deposits of bacteria on the nematode cuticle. The most nematicidal strain, Serratia sp. A88copa13, produced proteases in the supernatant. The use of selective inhibitors revealed that a serine protease with 70 kDa was majorly responsible for the toxicity of the supernatant. This extracellular serine protease is different phylogenetically, in size and biochemically from previously described proteases. Nematicidal assays revealed differences in nematicidal activity of the proteases to different species of Bursaphelenchus, suggesting its usefulness in a primary screen of the nematodes. This study offers the basis for further investigation of PWD and brings new insights on the role bacteria play in the defense of pine trees against B. xylophilus. Understanding all the factors involved is important in order to develop strategies to control B. xylophilus dispersion. PMID:24244546

Francisco, Romeu; Verissimo, Paula; Santos, Susana S.; Fonseca, Luís; Abrantes, Isabel M. O.; Morais, Paula V.

2013-01-01

299

Sampling for Regional Monitoring of Nematode Communities in Agricultural Soils  

PubMed Central

Regional assessment of nematode communities to monitor the condition or ecological health of agricultural soils requires sampling programs with measures of known reliability and the ability to detect differences over time. Numbers of fields sampled in a region, samples taken per field, and subsamples assayed per sample must be balanced with cost to provide the best sampling scheme. We used components of variance from statewide surveys in North Carolina (1992) and Nebraska (1993) to estimate number of (i) fields to be sampled; (ii) 20-core, composite soil samples to be obtained for each field; and (iii) subsamples to be assayed for each composite sample to detect a specified amount of change in index values within a geographic region. Variances for these three components were used to estimate the degree of reliability for five ecologically based indices (four measures of maturity and one of diversity) of nematode communities. Total variance for maturity and diversity indices, based upon communities of free-living nematodes, was greater in North Carolina than in Nebraska; the opposite was true for indices based strictly upon maturity of communities of plant-parasitic nematodes or of all nematodes in soil. Variability within samples was greater in North Carolina than in Nebraska, especially for maturity indices based only upon free-living nematodes. We identified two possible sampling strategies for a regional survey: Option 1, with two independent samples per field and a single subsample assayed per sample, which would provide a reliability ratio value ?0.6 for most indices; and Option 2, with three independent samples per field and two subsamples assayed per sample, which would provide a reliability ratio value ?0.7 for several indices. When cost was considered, Option 1 was the better strategy. Number of fields to be sampled within a region or state varied with the index chosen; with specific indices, however, a 10% change in mean index value could be detected with a sample of 50 to 100 fields. PMID:19277135

Neher, D. A.; Campbell, C. L.

1996-01-01

300

A nematode effector protein similar to annexins in host plants.  

PubMed

Nematode parasitism genes encode secreted effector proteins that play a role in host infection. A homologue of the expressed Hg4F01 gene of the root-parasitic soybean cyst nematode, Heterodera glycines, encoding an annexin-like effector, was isolated in the related Heterodera schachtii to facilitate use of Arabidopsis thaliana as a model host. Hs4F01 and its protein product were exclusively expressed within the dorsal oesophageal gland secretory cell in the parasitic stages of H. schachtii. Hs4F01 had a 41% predicted amino acid sequence identity to the nex-1 annexin of C. elegans and 33% identity to annexin-1 (annAt1) of Arabidopsis, it contained four conserved domains typical of the annexin family of calcium and phospholipid binding proteins, and it had a predicted signal peptide for secretion that was present in nematode annexins of only Heterodera spp. Constitutive expression of Hs4F01 in wild-type Arabidopsis promoted hyper-susceptibility to H. schachtii infection. Complementation of an AnnAt1 mutant by constitutive expression of Hs4F01 reverted mutant sensitivity to 75 mM NaCl, suggesting a similar function of the Hs4F01 annexin-like effector in the stress response by plant cells. Yeast two-hybrid assays confirmed a specific interaction between Hs4F01 and an Arabidopsis oxidoreductase member of the 2OG-Fe(II) oxygenase family, a type of plant enzyme demonstrated to promote susceptibility to oomycete pathogens. RNA interference assays that expressed double-stranded RNA complementary to Hs4F01 in transgenic Arabidopsis specifically decreased parasitic nematode Hs4F01 transcript levels and significantly reduced nematode infection levels. The combined data suggest that nematode secretion of an Hs4F01 annexin-like effector into host root cells may mimic plant annexin function during the parasitic interaction. PMID:19887499

Patel, Nrupali; Hamamouch, Noureddine; Li, Chunying; Hewezi, Tarek; Hussey, Richard S; Baum, Thomas J; Mitchum, Melissa G; Davis, Eric L

2010-01-01

301

Nematode Spatial and Ecological Patterns from Tropical and Temperate Rainforests  

PubMed Central

Large scale diversity patterns are well established for terrestrial macrobiota (e.g. plants and vertebrates), but not for microscopic organisms (e.g. nematodes). Due to small size, high abundance, and extensive dispersal, microbiota are assumed to exhibit cosmopolitan distributions with no biogeographical patterns. This assumption has been extrapolated from local spatial scale studies of a few taxonomic groups utilizing morphological approaches. Recent molecularly-based studies, however, suggest something quite opposite. Nematodes are the most abundant metazoans on earth, but their diversity patterns are largely unknown. We conducted a survey of nematode diversity within three vertical strata (soil, litter, and canopy) of rainforests at two contrasting latitudes in the North American meridian (temperate: the Olympic National Forest, WA, U.S.A and tropical: La Selva Biological Station, Costa Rica) using standardized sampling designs and sample processing protocols. To describe nematode diversity, we applied an ecometagenetic approach using 454 pyrosequencing. We observed that: 1) nematode communities were unique without even a single common species between the two rainforests, 2) nematode communities were unique among habitats in both rainforests, 3) total species richness was 300% more in the tropical than in the temperate rainforest, 4) 80% of the species in the temperate rainforest resided in the soil, whereas only 20% in the tropics, 5) more than 90% of identified species were novel. Overall, our data provided no support for cosmopolitanism at both local (habitats) and large (rainforests) spatial scales. In addition, our data indicated that biogeographical patterns typical of macrobiota also exist for microbiota. PMID:22984536

Porazinska, Dorota L.; Giblin-Davis, Robin M.; Powers, Thomas O.; Thomas, W. Kelley

2012-01-01

302

Control of Citrus Nematode, Tylenchulus seimipenetrans, with Cadusafos.  

PubMed

Granular (Rugby 10G) and liquid (Rugby 100 ME) formulations of cadusafos were evaluated for the control of Tylenchulus semipenetrans on mature lemon trees in a commercial citrus orchard at Yuma, Arizona. Three applications of cadusafos, with 2 months between applications, at the rate of 2 g a.i./m(2) reduced nematode populations to undetectable levels and increased the yield and rate of fruit maturity of 'Rosenberger' lemons. Yields were increased 12,587 kg/ha with Rugby 100ME and 8,392 kg/ha with Rugby 10G. Nematode populations were suppressed for at least 12 months after the last application. PMID:19277185

McClure, M A; Schmitt, M E

1996-12-01

303

Control of Citrus Nematode, Tylenchulus seimipenetrans, with Cadusafos  

PubMed Central

Granular (Rugby 10G) and liquid (Rugby 100 ME) formulations of cadusafos were evaluated for the control of Tylenchulus semipenetrans on mature lemon trees in a commercial citrus orchard at Yuma, Arizona. Three applications of cadusafos, with 2 months between applications, at the rate of 2 g a.i./m² reduced nematode populations to undetectable levels and increased the yield and rate of fruit maturity of 'Rosenberger' lemons. Yields were increased 12,587 kg/ha with Rugby 100ME and 8,392 kg/ha with Rugby 10G. Nematode populations were suppressed for at least 12 months after the last application. PMID:19277185

McClure, M. A.; Schmitt, M. E.

1996-01-01

304

Nematode Autofluorescence and Its Use as an Indicator of Viability  

PubMed Central

Representatives of 15 nematode genera were viewed with 450-490-nm epi-illumination and found to autofluoresce. The autofluorescence was limited to 1-5-?m-d globules in the intestinal cells of live nematodes. When adult Pratylenchus penetrans or Caenorhabditis elegans were killed with formaldehyde, freezing, or heat, autofluorescence dispersed throughout the body. Mixed stages of P. penetrans were killed by freezing at several different temperatures. Estimates of survival based on autofluorescence dispersal matched estimates based on mobility more closely than did estimates based on the vital stain, eosin-y. PMID:19287626

Forge, T. A.; MacGuidwin, A. E.

1989-01-01

305

Stacking resistance to crown gall and nematodes in walnut rootstocks  

PubMed Central

Background Crown gall (CG) (Agrobacterium tumefaciens) and the root lesion nematodes (RLNs) (Pratylenchus vulnus) are major challenges faced by the California walnut industry, reducing productivity and increasing the cost of establishing and maintaining orchards. Current nematode control strategies include nematicides, crop rotation, and tolerant cultivars, but these methods have limits. Developing genetic resistance through novel approaches like RNA interference (RNAi) can address these problems. RNAi-mediated silencing of CG disease in walnut (Juglans regia L.) has been achieved previously. We sought to place both CG and nematode resistance into a single walnut rootstock genotype using co-transformation to stack the resistance genes. A. tumefaciens, carrying self-complimentary iaaM and ipt transgenes, and Agrobacterium rhizogenes, carrying a self-complimentary Pv010 gene from P. vulnus, were used as co-transformation vectors. RolABC genes were introduced by the resident T-DNA in the A. rhizogenes Ri-plasmid used as a vector for plant transformation. Pv010 and Pv194 (transgenic control) genes were also transferred separately using A. tumefaciens. To test for resistance, transformed walnut roots were challenged with P. vulnus and microshoots were challenged with a virulent strain of A. tumefaciens. Results Combining the two bacterial strains at a 1:1 rather than 1:3 ratio increased the co-transformation efficiency. Although complete immunity to nematode infection was not observed, transgenic lines yielded up to 79% fewer nematodes per root following in vitro co-culture than untransformed controls. Transgenic line 33-3-1 exhibited complete crown gall control and 32% fewer nematodes. The transgenic plants had thicker, longer roots than untransformed controls possibly due to insertion of rolABC genes. When the Pv010 gene was present in roots with or without rolABC genes there was partial or complete control of RLNs. Transformation using only one vector showed 100% control in some lines. Conclusions CG and nematode resistance gene stacking controlled CG and RLNs simultaneously in walnuts. Silencing genes encoding iaaM, ipt, and Pv010 decrease CG formation and RLNs populations in walnut. Beneficial plant genotype and phenotype changes are caused by co-transformation using A. tumefaciens and A. rhizogenes strains. Viable resistance against root lesion nematodes in walnut plants may be accomplished in the future using this gene stacking technology. PMID:24083348

2013-01-01

306

Statistical and Economic Techniques for Site-specific Nematode Management.  

PubMed

Recent advances in precision agriculture technologies and spatial statistics allow realistic, site-specific estimation of nematode damage to field crops and provide a platform for the site-specific delivery of nematicides within individual fields. This paper reviews the spatial statistical techniques that model correlations among neighboring observations and develop a spatial economic analysis to determine the potential of site-specific nematicide application. The spatial econometric methodology applied in the context of site-specific crop yield response contributes to closing the gap between data analysis and realistic site-specific nematicide recommendations and helps to provide a practical method of site-specifically controlling nematodes. PMID:24643451

Liu, Zheng; Griffin, Terry; Kirkpatrick, Terrence L

2014-03-01

307

Stem nematode counteracts plant resistance of aphids in alfalfa, Medicago sativa.  

PubMed

Plants are exploited by a diverse community of insect herbivores and phytopathogens that interact indirectly through plant-mediated interactions. Generally, plants are thought to respond to insects and pathogens through different defensive signaling pathways. As plants are selected for resistance to one phytophagous organism type (insect vs. pathogen) in managed systems, it is not clear how this selection may affect community interactions. This study examined the effect of nematode-resistant varieties on aphid (Acyrthosiphon pisum) suppression, and then determined how infection by the stem nematode, Ditylenchus dipsaci, mediated ecological effects on aphids and on plant defense proteins. Four alfalfa (Medicago sativa) varieties were selected with resistance to nematodes only (+,-), aphids only (-,+), nematodes and aphids (+,+), and susceptibility to nematodes and aphids (-,-). Field and greenhouse experiments were conducted to isolate the effect of nematode infection and aphid abundance on each variety. We found that varieties resistant to nematode, regardless of aphid resistance, had the lowest aphid counts, suggesting possible cross-resistance. Aphid abundance, however, increased when plants were exposed to nematodes. Resistant varieties were associated with elevated saponins but these compounds were not affected by insect or pathogen feeding. Concentrations of peroxidases and trypsin inhibitors, however, were increased in nematode resistant varieties when exposed to nematodes and aphids, respectively. The patterns of plant defense were variable, and a combination of resistance traits and changes in nutrient availability may drive positive interactions between nematodes and aphids aboveground. PMID:25261892

Ramirez, Ricardo A; Spears, Lori R

2014-10-01

308

Discovery and initial analysis of novel viral genomes in the soybean cyst nematode.  

PubMed

Nematodes are the most abundant multicellular animals on earth, yet little is known about their natural viral pathogens. To date, only two nematode virus genomes have been reported. Consequently, nematode viruses have been overlooked as important biotic factors in the study of nematode ecology. Here, we show that one plant parasitic nematode species, Heterodera glycines, the soybean cyst nematode (SCN), harbours four different RNA viruses. The nematode virus genomes were discovered in the SCN transcriptome after high-throughput sequencing and assembly. All four viruses have negative-sense RNA genomes, and are distantly related to nyaviruses and bornaviruses, rhabdoviruses, bunyaviruses and tenuiviruses. Some members of these families replicate in and are vectored by insects, and can cause significant diseases in animals and plants. The novel viral sequences were detected in both eggs and the second juvenile stage of SCN, suggesting that these viruses are transmitted vertically. While there was no evidence of integration of viral sequences into the nematode genome, we indeed detected transcripts from these viruses by using quantitative PCR. These data are the first finding of virus genomes in parasitic nematodes. This discovery highlights the need for further exploration for nematode viruses in all tropic groups of these diverse and abundant animals, to determine how the presence of these viruses affects the fitness of the nematode, strategies of viral transmission and mechanisms of viral pathogenesis. PMID:21490246

Bekal, Sadia; Domier, Leslie L; Niblack, Terry L; Lambert, Kris N

2011-08-01

309

Genome Similarity Implies that Citrus-Parasitic Burrowing Nematodes do not Represent a Unique Species.  

PubMed

Burrowing nematodes from Central America, Dominican Republic, Florida, Guadeloupe, Hawaii, and Puerto Rico were characterized for their ability to parasitize citrus, but citrus parasites were found only in Florida. Sequence tag sites originally amplified from a citrus-parasitic burrowing nematode were polymorphic among 37 burrowing nematode isolates and were not correlated with citrus parasitism, nematode isolate collection site, or amplification of a 2.4-kb sequence tag site (DK#1). Results of a RAPD analysis and characterization of the isozymes phosphoglucose isomerase, lactate dehydrogenase, and malate dehydrogenase indicated that the burrowing nematode isolates were highly similar. Citrus parasitism in Florida appears to be associated with limited changes in the burrowing nematode genome. Findings did not substantiate a previous report that R. citrophilus was present in Hawaii. Overall, these data do not support assignment of sibling species status to burrowing nematodes that differ with respect to citrus parasitism. PMID:19274179

Kaplan, D T; Opperman, C H

1997-12-01

310

Correlation of Edaphic Factors with Plant-parasitic Nematode Population Densities in a Forage Field  

PubMed Central

Two hundred soil samples from the Ap horizon of a reed canarygrass field overlaying several different but related soils in northern Minnesota were analyzed for plant-parasitic nematodes and 22 edaphic factors. Pratylenchus penetrans was the predominant nematode taxon. Others were Aglenchus agricola, Tylenchorhynchus spp., Heterodera trifolii, Paratylenchus spp., Tylenchus maius, and Criconemella sp. Five nematode taxa, P. penetrans, A, agricola, Tylenchorhynchus spp., H. trifolii, and Paratylenchus spp., were correlated with particle size, Tylenchus maius and Criconemella sp. were correlated with effective cation exchange capacity. Nematode field spatial arrangements were related to a combination of statistically significant positive and negative soil factor effects on the nematode populations. Contour maps derived by geostatistical techniques were used to visually validate statistically significant correlations of nematode and soil data. Contour mapping to supplement traditional statistical techniques can be used to achieve a more holistic approach to studies of nematode-soil interrelationships. PMID:19279821

Wallace, M. K.; Rust, R. H.; Hawkins, D. M.; MacDonald, D. H.

1993-01-01

311

Soybean Cyst Nematode SDS-PAGE Protein Characterization  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) represent one of the most serious threats to the stability of soybean crops in the United States. Initially discovered in North Carolina in the 1950s, it has spread rapidly through the Midwest generating an estimated $1 billion in failed crop...

312

Influence of fungicides on a nematode-suppressive soil  

Technology Transfer Automated Retrieval System (TEKTRAN)

We identified a field in Georgia, USA that was moderately suppressive to Meloidogyne spp. In the greenhouse, reproduction of both M. incognita on cotton and M. arenaria on peanut was greater in microwave-heated soil than in natural soil from this field suggesting that nematode suppression was cause...

313

PLANT PROBLEM CLINIC & NEMATODE ASSAY LAB SUPPLIES ORDER FORM  

E-print Network

PLANT PROBLEM CLINIC & NEMATODE ASSAY LAB SUPPLIES ORDER FORM Type the name of your County@clemson.edu or sprsn@clemson.edu REQUESTING OFFICE/COUNTY County Name: PLANT PROBLEM CLINIC SUPPLIES ITEM No. Requested Plant Problem Clinic Sampling Guidelines Plastic Sample Bags: (10 per Bundle) Small Large Order

Duchowski, Andrew T.

314

Evaluation of coffee genotypes for root-knot nematode resistance  

Technology Transfer Automated Retrieval System (TEKTRAN)

Meloidogyne konaensis causes severe damage to the root systems of Coffea arabica cv. Typica ‘Guatemala’ grown in Kona, Hawaii. Farmers currently employ grafting of the nematode tolerant C. liberica var. dewevrei ‘Fukunaga’ to C. arabica cv. Typica scions. Greenhouse experiments confirmed C. liberi...

315

Olfaction shapes host-parasite interactions in parasitic nematodes.  

PubMed

Many parasitic nematodes actively seek out hosts in which to complete their lifecycles. Olfaction is thought to play an important role in the host-seeking process, with parasites following a chemical trail toward host-associated odors. However, little is known about the olfactory cues that attract parasitic nematodes to hosts or the behavioral responses these cues elicit. Moreover, what little is known focuses on easily obtainable laboratory hosts rather than on natural or other ecologically relevant hosts. Here we investigate the olfactory responses of six diverse species of entomopathogenic nematodes (EPNs) to seven ecologically relevant potential invertebrate hosts, including one known natural host and other potential hosts collected from the environment. We show that EPNs respond differentially to the odor blends emitted by live potential hosts as well as to individual host-derived odorants. In addition, we show that EPNs use the universal host cue CO(2) as well as host-specific odorants for host location, but the relative importance of CO(2) versus host-specific odorants varies for different parasite-host combinations and for different host-seeking behaviors. We also identified host-derived odorants by gas chromatography-mass spectrometry and found that many of these odorants stimulate host-seeking behaviors in a species-specific manner. Taken together, our results demonstrate that parasitic nematodes have evolved specialized olfactory systems that likely contribute to appropriate host selection. PMID:22851767

Dillman, Adler R; Guillermin, Manon L; Lee, Joon Ha; Kim, Brian; Sternberg, Paul W; Hallem, Elissa A

2012-08-28

316

Nematodes associated with pawpaw (cv. homestead) in Nsukka, Nigeria.  

PubMed

In field and greenhouse experiments, Meloidogyne javanica caused symptomatic damage to pawpaw (cv. Homestead). Other important nematodes to which pawpaw seemed a good host included Pratylenchus spp., Rotylenchus reniformis, Helioctylenchus spp., and Tylenchulus martini. Pawpaw appeared as a poor host to Scutellonema clatbricaudatum and Hoplolaimus pararobustus. Fusarium sp. was isolated from the plant roots. PMID:7342958

Ogbuji, R O

1981-01-01

317

Response of Pinus ponderosa Seedlings to Stylet-Bearing Nematodes.  

PubMed

Of 12 stylet-bearing nematodes used for inoculations, Pratylenchus penetrans, P. brachyurus, P. vulnus, Ditylenchus destructor, Meloidogyne incognita, M. javanica, and M. hapla reproduced on Pinus ponderosa, while Xiphinema index, Aphelenchus avenae, Paratylenehus neoamblycephalus, Tylenchulus semipenetrans, and Macroposthonia xenoplax did not. P. vulnus, P. brachyurus, P. penetrans, A. avenae, D. destructor, T. semipenetrans, and P. neoamblycephalus significantly suppressed both the shoot and root wet weights of ponderosa pine seedlings obtained from stands in five different locations. X. index significantly suppressed root wet weights, M. xenoplax siguificantly suppressed shoot wet weight, and M. incognita, M. javanica, and M. hapla suppressed neither at the inoculation levels used. Injurious nematodes tended to suppress root growth more than shoot growth. Seedlings from two locations produced greater shoot growth wet weight than did seedlings from the other three locations. The more injurious nematodes tended to cause an increase in the water content of shoots. Frequency analyses of seedling population shoot-root ratios indicated that ponderosa pine seedlings could be selected for better shoot-root ratios as well as for resistance to several pathogenic nematodes. PMID:19300659

Viglierchio, D R

1979-10-01

318

ENTOMOPATHOGENIC NEMATODES AND INSECTS: DIRECT AND ACTIVE INFECTION  

Technology Transfer Automated Retrieval System (TEKTRAN)

In nature, entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) must infect an insect host in order to complete their life cycle. The decision to infect or not is critical because once inside the host there is no turning back. Here, we review and analyze infection behavior of entomo...

319

IDENTIFICATION OF SOYBEAN CYST NEMATODE LETHAL GENES USING COMPUTATIONAL METHODS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean cyst nematode (SCN; Heterodera glycines) is a devastating pest of soybean causing one billion dollars in losses to the US economy per year and over ten billion worldwide. The genome sequence of SCN is not well characterized nor fully sequenced. On the other hand Caenorhabditis elegans genome...

320

DNA barcoding of parasitic nematodes: is it kosher?  

PubMed

Nematode parasites were encountered in kosher-certified fish meat and roe, and the question was raised as to whether or not these food products were kosher as concerns food preparation standards-a matter that pertains to the identity and, by extension, the life cycle of the parasites. To ascertain the identities of parasitic nematodes, given the distorted or damaged nature of the specimens, molecular techniques were applied in the form of DNA barcoding. To our knowledge, this is the first application of this technique to an obviously cultural concern as opposed to one of health or economic significance. Results, based both on cytochrome c oxidase subunits I and II, suggested that the parasite species found in the fish products are anisakine species that do not inhabit the intestinal lumen of the fish hosts examined. Thus, there was no evidence of failure to adhere to food preparation practices consistent with the proscriptions of Orthodox Judaism. Notwithstanding the success of DNA barcoding in determining at least the higher taxonomic identities of the parasites, some shortcomings of the DNA barcoding pipeline as it pertains to nematode parasites were encountered; specifically, the paucity of data available for the DNA barcoding locus, even for very common nematode taxa. PMID:22300283

Siddall, Mark E; Kvist, Sebastion; Phillips, Anna; Oceguera-Figuero, Alejandro

2012-06-01

321

Detecting Microbial Nucleic Acids within Nematode Bodies: A Photo Essay  

Technology Transfer Automated Retrieval System (TEKTRAN)

We developed a taxa-specific, fluorescence in situ hybridization (FISH) technique to localize microbial nucleic acids within nematode bodies. This technique involves hybridization of a nucleic acid probe to target microbial sequences. Hybridization is detected microscopically, as the probes have f...

322

The Wolbachia endosymbiont as an anti-filarial nematode target  

PubMed Central

Human disease caused by parasitic filarial nematodes is a major cause of global morbidity. The parasites are transmitted by arthropod intermediate hosts and are responsible for lymphatic filariasis (elephantiasis) or onchocerciasis (river blindness). Within these filarial parasites are intracellular alpha-proteobacteria, Wolbachia, that were first observed almost 30 years ago. The obligate endosymbiont has been recognized as a target for anti-filarial nematode chemotherapy as evidenced by the loss of worm fertility and viability upon antibiotic treatment in an extensive series of human trials. While current treatments with doxycycline and rifampicin are not practical for widespread use due to the length of required treatments and contraindications, anti-Wolbachia targeting nevertheless appears a promising alternative for filariasis control in situations where current programmatic strategies fail or are unable to be delivered and it provides a superior efficacy for individual therapy. The mechanisms that underlie the symbiotic relationship between Wolbachia and its nematode hosts remain elusive. Comparative genomics, bioinfomatic and experimental analyses have identified a number of potential interactions, which may be drug targets. One candidate is de novo heme biosynthesis, due to its absence in the genome sequence of the host nematode, Brugia malayi, but presence in Wolbachia and its potential roles in worm biology. We describe this and several additional candidate targets, as well as our approaches for understanding the nature of the host-symbiont relationship. PMID:20730111

Taylor, Mark J.; Foster, Jeremy M.

2010-01-01

323

Radiation Effects on Nematodes: Results from IML-1 Esperiments  

NASA Technical Reports Server (NTRS)

The nematode Caenorhabditis elegans was exposed to natural space radiation using the ESA Biorack facility aboard Spacelab on International Microgravity Laboratory 1, STS-42. For the major experimental objective dormant animals were suspended in buffer or on agar or immobilized next to CR-39 plactic nuclear track detectors to correlate fluence of HZE particles with genetic events.

Nelson, G. A.; Schubert, W. W.; Kazarians, G. A.; Righards, G. F.; Benton, E. V; Benton, E. R.; Henke, R.

1993-01-01

324

Natural variation in chemosensation: lessons from an island nematode  

PubMed Central

All organisms must interact with their environment, responding in behavioral, chemical, and other ways to various stimuli throughout their life cycles. Characterizing traits that directly represent an organism's ability to sense and react to their environment provides useful insight into the evolution of life-history strategies. One such trait for the nematode Pristionchus pacificus, chemosensation, is involved in navigation to beetle hosts. Essential for the survival of the nematode, chemosensory behavior may be subject to variation as nematodes discriminate among chemical cues to complete their life cycle. We examine this hypothesis using natural isolates of P. pacificus from La Réunion Island. We select strains from a variety of La Réunion beetle hosts and geographic locations and examine their chemoattraction response toward organic compounds, beetle washes, and live beetles. We find that nematodes show significant differences in their response to various chemicals and are able to chemotax to live beetles in a novel assay. Further, strains can discriminate among different cues, showing more similar responses toward beetle washes than to organic compounds in cluster analyses. However, we find that variance in chemoattraction response is not significantly associated with temperature, location, or beetle host. Rather, strains show a more concerted response toward compounds they most likely directly encounter in the wild. We suggest that divergence in odor-guided behavior in P. pacificus may therefore have an important ecological component. PMID:24455150

McGaughran, Angela; Morgan, Katy; Sommer, Ralf J

2013-01-01

325

Heme requirement for reproduction of a free-living nematode.  

PubMed

The free-living hermaphroditic nematode Caernorhabditis briggsae has a nutritional requirement for heme. The organism can be subcultured repeatedly in a chemically defined axenic medium that contains autoclaved bacterial cells (Escherichia coli) and sterols if a hemeprotein-containing fraction from liver is present. Pure myoglobin, hemoglobin, cytochrome c, and hemin, respectively, can substitute effectively for the liver fraction. PMID:5417058

Hieb, W F; Stokstad, E L; Rothstein, M

1970-04-01

326

HOST STATUS OF TROPICAL SPIDERWORT (COMMELINA BENGHALENSIS) FOR NEMATODES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nematodes are the most damaging pathogens of cotton, and one of the most important pathogens of peanut. Crop rotations utilizing cotton, peanut, and corn are used to manage the southern root-knot (Meloidogyne incognita), peanut root-knot (M. arenaria), and reniform (Rotylenchulus reniformis) nemato...

327

The differentiation of parasitic nematodes using random amplified polymorphic DNA.  

PubMed

DNA from species and races of plant parasitic nematodes (Meloidogyne, Globodera and Heterodera) and a human parasitic nematode (Trichinella) were subjected to polymerase chain reaction amplification using one arbitrary primer (M-10). This technique results in relatively simple DNA profiles that include polymorphic markers known as random amplified polymorphic DNA (RAPDs). The RAPD profiles of the plant nematode species of Meloidogyne made possible the identification of M. incognita and M. hapla, but no differences were found between the patterns of M. javanica, M. arenaria and M. graminicola. Moreover, the four races of M. incognita were indistinguishable by this primer. In contrast, when races of the plant nematode Globodera rostochiensis (Ro1 and Ro2/3) were studied under the same RAPDs conditions, a race specific profile allows these two most devastating races to be differentiated. When DNAs of eight Trichinella isolates were subjected to RAPD studies, four different patterns were identified, corresponding to the four Trichinella clusters previously defined by isozyme polymorphism. PMID:7930450

Chacón, M R; Rodriguez, E; Parkhouse, R M; Burrows, P R; Garate, T

1994-06-01

328

Soybean Cyst Nematode Infects Roots of Sugar Beet  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean cyst nematode (SCN; Heterodera glycines) is the most important pest of soybean in the world. With the increase of soybean production in the Red River Valley of North Dakota and Minnesota over the past decades, SCN has become a growing threat to local soybean production. The sugar beet cyst...

329

Amphiregulin-a Th2 cytokine enhancing resistance to nematodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Intestinal nematode infections remain a major health threat to humans despite improved sanitation. Protection is mainly mediated by Type 2-biased immune responses, characterized by Th2 lymphocytes and other cells secreting a set of cytokines including Interleukin 4 (IL-4), IL-5, IL-10, and IL-13. I...

330

Noncanonical cell death programs in the nematode Caenorhabditis elegans  

E-print Network

Review Noncanonical cell death programs in the nematode Caenorhabditis elegans ES Blum1 , M (caspase), which function in a linear pathway to promote developmental cell death in this organism. While this core pathway functions in many cells, recent studies suggest that additional regulators, acting

Shaham, Shai

331

Evaluation of some Vulval Appendages in Nematode Taxonomy  

Technology Transfer Automated Retrieval System (TEKTRAN)

A survey of the nature and phylogenetic distribution of nematode vulval appendages revealed three major classes based on composition, position and orientation: membranes, flaps, and epiptygma. Minor classes included cuticular inflations, vulval tubes of extruded gonadal tissues, vulval ridges, and p...

332

Vertical Distribution of Bacterivorous Nematodes under Different Wenju Liang,1  

E-print Network

Vertical Distribution of Bacterivorous Nematodes under Different Land Uses Wenju Liang,1 Xiaoke Zhang,1,3 Qi Li,1,3 Yong Jiang,1 Wei Ou,1,3 and Deborah A. Neher2 Abstract: The vertical distribution. In contrast, Chiloplacus and Prismatolaimus spp. were distributed down to 100-cm depth in the AC and CM

Neher, Deborah A.

333

Managing Plant-Parasitic Nematodes in Established Red Raspberry Fields  

Technology Transfer Automated Retrieval System (TEKTRAN)

The efficacy and phytotoxicity of post-plant treatments to control root lesion [Pratylenchus penetrans (Cobb), Chitwood & Otiefa] and dagger (Xiphinema bakeri Williams) nematodes in red raspberry (Rubus idaeus L.) were evaluated in four field studies conducted over three years. Spring spray applicat...

334

The Feeding Tube of Cyst Nematodes: Characterisation of Protein Exclusion  

PubMed Central

Plant parasitic nematodes comprise several groups; the most economically damaging of these are the sedentary endoparasites. Sedentary endoparasitic nematodes are obligate biotrophs and modify host root tissue, using a suite of effector proteins, to create a feeding site that is their sole source of nutrition. They feed by withdrawing host cell assimilate from the feeding site though a structure known as the feeding tube. The function, composition and molecular characteristics of feeding tubes are poorly characterised. It is hypothesised that the feeding tube facilitates uptake of host cell assimilate by acting as a molecular sieve. Several studies, using molecular mass as the sole indicator of protein size, have given contradictory results about the exclusion limits of the cyst nematode feeding tube. In this study we propose a method to predict protein size, based on protein database coordinates in silico. We tested the validity of these predictions using travelling wave ion mobility spectrometry – mass spectrometry, where predictions and measured values were within approximately 6%. We used the predictions, coupled with mass spectrometry, analytical ultracentrifugation and protein electrophoresis, to resolve previous conflicts and define the exclusion characteristics of the cyst nematode feeding tube. Heterogeneity was tested in the liquid, solid and gas phase to provide a comprehensive evaluation of three proteins of particular interest to feeding tube size exclusion, GFP, mRFP and Dual PI. The data and procedures described here could be applied to the design of plant expressed defence compounds intended for uptake into cyst nematodes. We also highlight the need to assess protein heterogeneity when creating novel fusion proteins. PMID:24489891

Eves-van den Akker, Sebastian; Lilley, Catherine J.; Ault, James R.; Ashcroft, Alison E.; Jones, John T.; Urwin, Peter E.

2014-01-01

335

Mermithid nematodes found in adult Anopheles from southeastern Senegal  

PubMed Central

Background Over two dozen mermithid nematodes have been described parasitizing mosquitoes worldwide, however, only two species were found in Africa. Mermithid nematodes kill their mosquito host upon emergence, which suggests that they could be developed as biological control agents of mosquitoes. Both Romanomermis culicivorax and Romanomermis iyengari have been reared for mass release to control numerous Anopheles species vector populations, and in one instance this may have led to reduced malaria prevalence in a human population. Methods Anopheles mosquitoes were collected during a malaria study in southeastern Senegal. Two different adult blood fed mosquitoes had a single mermithid nematode emerge from their anus while they were being held post-capture. Primers from the 18?S rDNA were developed to sequence nematode DNA and screen mosquitoes for mermithid DNA. 18?S rDNA from the Senegalese mermithid and other mermithid entries in GenBank were used to create a Maximum Parsimony tree of the Mermithidae family. Results The mermithid was present in 1.8% (10/551) of the sampled adult Anopheles species in our study area. The mermithid was found in An. gambiae s.s., An. funestus, and An. rufipes from the villages of Ndebou, Boundoucondi, and Damboucoye. Maximum parsimony analysis confirmed that the nematode parasites found in Anopheles were indeed mermithid parasites, and of the mermithid sequences available in GenBank, they are most closely related to Strelkovimermis spiculatus. Conclusions To our knowledge, this is the first report of mermithids from adult Anopheles mosquitoes in Senegal. The mermithid appears to infect Anopheles mosquitoes that develop in diverse larval habitats. Although maximum parsimony analysis determined the mermithid was closely related to Strelkovimermis spiculatus, several characteristics of the mermithid were more similar to the Empidomermis genus. Future mermithid isolations will hopefully allow: formal taxonomic identification, laboratory colonization, determination of life history traits and species specificity, and characterize its usefulness as a biological control agent. PMID:22741946

2012-01-01

336

A sensory code for host seeking in parasitic nematodes  

PubMed Central

Summary Nematodes comprise a large phylum of both free-living and parasitic species that show remarkably diverse lifestyles, ecological niches, and behavioral repertoires. Parasitic species in particular often display highly specialized host-seeking behaviors that reflect their specific host preferences. Many host-seeking behaviors can be triggered by the presence of host odors, yet little is known about either the specific olfactory cues that trigger these behaviors or the neural circuits that underlie them. Heterorhabditis bacteriophora and Steinernema carpocapsae are phylogenetically distant insect-parasitic nematodes whose host-seeking and host-invasion behavior resembles that of some of the most devastating human- and plant-parasitic nematodes. Here we compare the olfactory responses of H. bacteriophora and S. carpocapsae infective juveniles (IJs) to those of Caenorhabditis elegans dauers, which are analogous life stages [1]. We show that the broad host range of these parasites results from their ability to respond to the universally-produced signal carbon dioxide (CO2) as well as a wide array of odors, including host-specific odors that we identified using TD-GC-MS. We show that CO2 is attractive for the parasitic IJs and C. elegans dauers despite being repulsive for C. elegans adults [2–4], and we identify an ancient and conserved sensory neuron that mediates CO2 response in both parasitic and free-living species regardless of whether CO2 is an attractive or a repulsive cue. Finally, we show that the parasites’ odor response profiles are more similar to each other than to that of C. elegans despite their greater phylogenetic distance, likely reflecting evolutionary convergence to insect parasitism. Our results suggest that the olfactory responses of parasitic versus free-living nematodes are highly diverse and that this diversity is critical to the evolution of nematode behavior. PMID:21353558

Hallem, Elissa A.; Dillman, Adler R.; Hong, Annie V.; Zhang, Yuanjun; Yano, Jessica M.; DeMarco, Stephanie F.

2011-01-01

337

Studies on the sublittoral free-living nematodes of Liverpool Bay. I. The structure and distribution of the nematode populations  

Microsoft Academic Search

Data collected from a survey of the benthic fauna of Liverpool Bay (UK) have been used to study the distribution and structure, in terms of percent age dominance and percent age frequency, of the nematode populations. Cluster analysis of the faunistic data from individual stations has shown that the populations are not sharply delimited. The relative proportions of their characteristic

A. R. Ward; N. Wales

1973-01-01

338

Potential of an Alkaline-stabilized Biosolid to Manage Nematodes: Case Studies on Soybean Cyst and Root-knot Nematodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

In 2001 a collaborative research effort was initiated to evaluate an alkaline stabilized biosolid amendment for plant-parasitic nematode management. This biosolid amendment, N-Viro Soil (NVS), is produced from a unique process that destroys pathogens through a combination of the following stresses:...

339

Overview of Organic Amendments for Management of Plant-Parasitic Nematodes, with Case Studies from Florida  

PubMed Central

Organic amendments have been widely used for management of plant-parasitic nematodes. Relatively rapid declines in nematode population levels may occur when decomposing materials release toxic compounds, while longer-term effects might include increases in nematode antagonists. Improved crop nutrition and plant growth following amendment use may lead to tolerance of plant-parasitic nematodes. Results depend on a great variety of factors such as material used, processing/composting of material, application rate, test arena, crop rotation and agronomic practices, soil type, climate, and other environmental factors. Reasons for variable performance and interpretation of results from amendment studies are discussed. Case studies of amendments for nematode management are reviewed from Florida, where composts and crop residues are the most frequently used amendments. Plant growth was often improved by amendment application, free-living nematodes (especially bacterivores) were often stimulated, but suppression of plant-parasitic nematodes was inconsistent. Amendments were generally not as effective as soil fumigation with methyl bromide for managing root-knot nematodes (Meloidogyne spp.), and often population levels or galling of root-knot nematodes in amended plots did not differ from those in non-amended control plots. While amendments may improve plant growth and stimulate soil food webs, additional study and testing are needed before they could be used reliably for management of plant-parasitic nematodes under Florida conditions. PMID:22791915

2011-01-01

340

Distribution and evolution of glycoside hydrolase family 45 cellulases in nematodes and fungi  

PubMed Central

Background Horizontal gene transfer (HGT) has been suggested as the mechanism by which various plant parasitic nematode species have obtained genes important in parasitism. In particular, cellulase genes have been acquired by plant parasitic nematodes that allow them to digest plant cell walls. Unlike the typical glycoside hydrolase (GH) family 5 cellulase genes which are found in several nematode species from the order Tylenchida, members of the GH45 cellulase have only been identified in a cluster including the families Parasitaphelenchidae (with the pinewood nematode Bursaphelenchus xylophilus) and Aphelenchoididae, and their origins remain unknown. Results In order to investigate the distribution and evolution of GH45 cellulase genes in nematodes and fungi we performed a wide ranging screen for novel putative GH45 sequences. This revealed that the sequences are widespread mainly in Ascomycetous fungi and have so far been found in a single major nematode lineage. Close relationships between the sequences from nematodes and fungi were found through our phylogenetic analyses. An intron position is shared by sequences from Bursaphelenchus nematodes and several Ascomycetous fungal species. Conclusions The close phylogenetic relationships and conserved gene structure between the sequences from nematodes and fungi strongly supports the hypothesis that nematode GH45 cellulase genes were acquired via HGT from fungi. The rapid duplication and turnover of these genes within Bursaphelenchus genomes demonstrate that useful sequences acquired via HGT can become established in the genomes of recipient organisms and may open novel niches for these organisms to exploit. PMID:24690293

2014-01-01

341

Sequence mining and transcript profiling to explore cyst nematode parasitism  

PubMed Central

Background Cyst nematodes are devastating plant parasites that become sedentary within plant roots and induce the transformation of normal plant cells into elaborate feeding cells with the help of secreted effectors, the parasitism proteins. These proteins are the translation products of parasitism genes and are secreted molecular tools that allow cyst nematodes to infect plants. Results We present here the expression patterns of all previously described parasitism genes of the soybean cyst nematode, Heterodera glycines, in all major life stages except the adult male. These insights were gained by analyzing our gene expression dataset from experiments using the Affymetrix Soybean Genome Array GeneChip, which contains probeset sequences for 6,860 genes derived from preparasitic and parasitic H. glycines life stages. Targeting the identification of additional H. glycines parasitism-associated genes, we isolated 633 genes encoding secretory proteins using algorithms to predict secretory signal peptides. Furthermore, because some of the known H. glycines parasitism proteins have strongest similarity to proteins of plants and microbes, we searched for predicted protein sequences that showed their highest similarities to plant or microbial proteins and identified 156 H. glycines genes, some of which also contained a signal peptide. Analyses of the expression profiles of these genes allowed the formulation of hypotheses about potential roles in parasitism. This is the first study combining sequence analyses of a substantial EST dataset with microarray expression data of all major life stages (except adult males) for the identification and characterization of putative parasitism-associated proteins in any parasitic nematode. Conclusion We have established an expression atlas for all known H. glycines parasitism genes. Furthermore, in an effort to identify additional H. glycines genes with putative functions in parasitism, we have reduced the currently known 6,860 H. glycines genes to a pool of 788 most promising candidate genes (including known parasitism genes) and documented their expression profiles. Using our approach to pre-select genes likely involved in parasitism now allows detailed functional analyses in a manner not feasible for larger numbers of genes. The generation of the candidate pool described here is an important enabling advance because it will significantly facilitate the unraveling of fascinating plant-animal interactions and deliver knowledge that can be transferred to other pathogen-host systems. Ultimately, the exploration of true parasitism genes verified from the gene pool delineated here will identify weaknesses in the nematode life cycle that can be exploited by novel anti-nematode efforts. PMID:19183474

Elling, Axel A; Mitreva, Makedonka; Gai, Xiaowu; Martin, John; Recknor, Justin; Davis, Eric L; Hussey, Richard S; Nettleton, Dan; McCarter, James P; Baum, Thomas J

2009-01-01

342

Relationships of Plant Parasitic Nematodes to Sites in Native Iowa Prairies  

PubMed Central

Soil samples were collected from three native Iowa prairies and analyzed for plant paiasitic nematodes and selected soil properties. Sites or nematodes were clustered with similarities related to habitat by a cluster analysis of site by nematode species and of nematodes by site. Some nematodes occurred in a wide range of prairie habitats, whereas others were more restricted. For example, greater numbers of Xiphinema americanum were in the low, well-drained sites than in the low wet sites or upland dry sites. Wet sites contained fewer nematodes than well-drained sites. Well-drained sites contained mainly Tylenchorhynchus maximus, Helicotylenchus pseudorobustus, and X. americanum. Wetter sites contained almost exclusively X. chambersi, H. hydrophilus, Telylenchus joctus, and an undescribed species of Tylenchorhynchus. PMID:19319267

Schmitt, D. P.; Norton, D. C.

1972-01-01

343

Alternatives to Fenamiphos for Management of Plant-Parasitic Nematodes on Bermudagrass  

PubMed Central

Plant-parasitic nematodes can be very damaging to turfgrasses. The projected cancellation of the registration for fenamiphos in the near future has generated a great deal of interest in identifying acceptable alternative nematode management tactics for use on turfgrasses. Two field experiments were conducted to evaluate the effectiveness of repeated applications of several commercially available nematicides and root biostimulants for reducing population densities of plant-parasitic nematodes and (or) promoting health of bermudagrass in nematode-infested soil. One experimental site was infested with Hoplolaimus galeatus and Trichodorus obtusus, the second with Belonolaimus longicaudatus. In both trials, none of the experimental treatments reduced population densities (P ? 0.1) of plant-parasitic nematodes, or consistently promoted turf visual performance or turf root production. Nematologists with responsibility to advise turf managers regarding nematode management should thoroughly investigate the validity of product claims before advising clientele in their use. PMID:19262894

Crow, W. T.

2005-01-01

344

Augmentation and Aldicarb Treatment of Nematodes in Selected Sugarcane Weed Habitats  

PubMed Central

In a single experiment, field-grown Louisiana sugarcane was augmented with phytoparasitic nematodes, treated with aldicarb, or left untreated in both weedy and weed-free habitats to study interactions among nematodes, weeds, sugarcane, and sugarcane free amino acid titers. Aldicarb reduced three of the six phytoparasitic nematode genera at various times during the two growing seasons and was associated with 17% more free proline in the sugarcane. Nematode augmentation resulted in higher field populations of Meloidogyne spp. Free cysteine, histidine, proline, and serine concentrations in sugarcane were lower where nematodes were added. Densities of Tylenchorhynchus annulatus and total phytoparasitic nematodes were lower in weedy habitats compared to weed-free conditions. Sixteen of the 17 sugarcane free amino acids were significantly lower in weed-free areas. It is suggested that further research be conducted on the relationship of plant stresses to free amino acid levels to better understand plant-mediated interactions among crop pests. PMID:19283191

Showler, A. T.; Reagan, T. E.; Flynn, J. L.

1991-01-01

345

Integrated signaling networks in plant responses to sedentary endoparasitic nematodes: a perspective.  

PubMed

Sedentary plant endoparasitic nematodes can cause detrimental yield losses in crop plants making the study of detailed cellular, molecular, and whole plant responses to them a subject of importance. In response to invading nematodes and nematode-secreted effectors, plant susceptibility/resistance is mainly determined by the coordination of different signaling pathways including specific plant resistance genes or proteins, plant hormone synthesis and signaling pathways, as well as reactive oxygen signals that are generated in response to nematode attack. Crosstalk between various nematode resistance-related elements can be seen as an integrated signaling network regulated by transcription factors and small RNAs at the transcriptional, posttranscriptional, and/or translational levels. Ultimately, the outcome of this highly controlled signaling network determines the host plant susceptibility/resistance to nematodes. PMID:25208657

Li, Ruijuan; Rashotte, Aaron M; Singh, Narendra K; Weaver, David B; Lawrence, Kathy S; Locy, Robert D

2015-01-01

346

Resistance to the Reniform Nematode in Selected Soybean Cultivars and Germplasm Lines  

PubMed Central

Reproduction indices from multiple tests were conducted to show the suitability of several soybean cultivars and germplasm lines as hosts of the reniform nematode Rotylenchulus reniformis. Sixteen soybean germplasm lines of 45 reported as resistant to soybean cyst nematode were also resistant to reinform nematode. Cultivars Peking and Pickett, and PI 90763, used as differentials in the standardized soybean cyst nematode race determination test, were resistant to reniform nematode. The differential PI 88788 and the soybean cyst nematode susceptible test standard cv. Lee were susceptible. The 16 soybean cultivars most commonly grown in Arkansas in 1992 were susceptible, whereas cv. Cordell, with PI 90763 in its parentage, and cv. Hartwig, with PI 437654 in its parentage, were resistant. PMID:19277183

Robbins, R. T.; Rakes, L.

1996-01-01

347

Parasitism of Nematodes by the Fungus Hirsutella rhossiliensis as Affected by Certain Organic Amendments  

PubMed Central

Experiments were conducted to determine whether the addition of organic matter to soil increased numbers of bacterivorous nematodes and parasitic activity of the nematophagous fungus Hirsutella rhossiliensis. In a peach orchard on loamy sand, parasitism of the plant-parasitic nematode Criconemella xenoplax by H. rhossiliensis was slightly suppressed and numbers of C. xenoplax were not affected by addition of 73 metric tons of composted chicken manure/ha. In the laboratory, numbers of bacterivorous nematodes (especially Acrobeloides spp.) and fungivorous nematodes increased but parasitism of nematodes by H. rhossiliensis usually decreased with addition of wheat straw or composted cow manure to a loamy sand naturally infested with H. rhossiliensis. These results do not support the hypothesis that organic amendments will enhance parasitism of nematodes by H. rhossiliensis. PMID:19279878

Jaffee, B. A.; Ferris, H.; Stapleton, J. J.; Norton, M. V. K.; Muldoon, A. E.

1994-01-01

348

Reflections on Plant and Soil Nematode Ecology: Past, Present and Future  

PubMed Central

The purpose of this review is to highlight key developments in nematode ecology from its beginnings to where it stands today as a discipline within nematology. Emerging areas of research appear to be driven by crop production constraints, environmental health concerns, and advances in technology. In contrast to past ecological studies which mainly focused on management of plant-parasitic nematodes, current studies reflect differential sensitivity of nematode faunae. These differences, identified in both aquatic and terrestrial environments include response to stressors, environmental conditions, and management practices. Methodological advances will continue to influence the role nematodes have in addressing the nature of interactions between organisms, and of organisms with their environments. In particular, the C. elegans genetic model, nematode faunal analysis and nematode metagenetic analysis can be used by ecologists generally and not restricted to nematologists. PMID:23482864

Ferris, Howard; Griffiths, Bryan S.; Porazinska, Dorota L.; Powers, Thomas O.; Wang, Koon-Hui; Tenuta, Mario

2012-01-01

349

Grain Yield and Heterosis of Maize Hybrids under Nematode Infested and Nematicide Treated Conditions  

PubMed Central

Plant-parasitic nematodes are present on maize but resistant genotypes have not been identified in Uganda. This study was aimed at determining the level of nematode resistance among F1 hybrids, and to estimate grain yield, heterosis and yield losses associated with maize hybrids under nematode infestation. The 30 F1 hybrids and two local checks were evaluated in a split plot design with nematode treatment (nematode infested versus nematicide treated) as the whole plot factor, and the hybrids as subplot factors arranged in an 8 x 4 alpha-lattice design. The experiment was conducted simultaneously at three sites. The hybrids were also evaluated in a split plot design under greenhouse conditions at IITA-Namulonge. Results revealed 24 P. zeae susceptible hybrids compared to only six P. zeae resistant hybrids. Grain yield across sites was higher by about 400 kg ha-1 under nematicide treatment than under nematode infestation. The nematode tolerant/resistant hybrids exhibited yields ranging from 5.0 to 8.4 t ha-1 compared to 5.0 t ha-1 obtained from the best check. Grain yield loss was up to 28% among susceptible hybrids, indicating substantial economic yield losses due to nematodes. Under field conditions, desired heterosis was recorded on 18 hybrids for P. zeae, and on three hybrids for Meloidogyne spp. Under nematode infestation, only 16 hybrids had higher relative yield compared to the mean of both checks, the best check and the trial mean, whereas it was 20 hybrids under nematicide treated plots. Overall, most outstanding hybrids under nematode infestation were CML395/MP709, CML312/5057, CML312/CML206, CML312/CML444, CML395/CML312 and CML312/CML395. Therefore, grain yield loss due to nematodes is existent but can be significantly reduced by growing nematode resistant hybrids. PMID:23429435

Kagoda, Frank; Derera, John; Tongoona, Pangirayi; Coyne, Daniel L.; Talwana, Herbert L.

2011-01-01

350

Resistance to Root-knot, Reniform, and Soybean Cyst Nematodes in Selected Soybean Breeding Lines  

PubMed Central

Soybean breeding lines and reported sources of nematode resistance were evaluated in repeated greenhouse tests for resistance to North Carolina populations of the soybean cyst nematode Heterodera glycines, reniform nematode Rotylenchulus reniformis, and the root-knot nematode species Meloidogyne incognita, M. arenaria, and M. arenaria. Lines from the soybean breeding program in Missouri that had 'Hartwig' soybean as a parent were the most resistant to races 1-4 of the soybean cyst nematode and the population of reniform nematode evaluated here. Numerous cysts of an inbred soybean cyst nematode race 4 population were produced on several of these Hartwig descendants, however, and accession $92-1603 had a cyst index of 29.2%. These accessions were also susceptible to M. arenaria and M. arenaria. Soybean lines N87-539 and N91-245 from the breeding program in North Carolina had strong resistance to an inbred soybean cyst nematode race 1 population and to M. arenaria, respectively. Soybean germplasm from the Georgia breeding program demonstrated the strongest resistance to the root-knot nematode species tested. Lines from the Georgia program, including G80-1515, G83-559, G93-9106, and G93-9223, that incorporated both root-knot and soybean cyst nematode resistance had the best overall resistance to the nematode populations evaluated. Resistance reported in the soybean lines was generally upheld. In a few cases, differences in the origin and culture of the nematode populations used in this study may have led to discrepancies between reported and observed resistance. PMID:19274243

Davis, E. L.; Meyers, D. M.; Burton, J. W.; Barker, K. R.

1998-01-01

351

Evaluation of fallow and cover crops for nematode suppression in three agroecologies of south western Nigeria  

Microsoft Academic Search

A study was conducted in three agroecological zones of south-western Nigeria to evaluate the effect of siam weed (Chromolaena odorata) and mucuna (Mucuna utilis) cover\\/fallow crops on plant-parasitic nematode population. The natural bush regrowth was used as control. Plant-parasitic nematodes were identified and counted during the fallow periods. Eleven genera of nematodes were identified and three (Meloidogyne, Pratylenchus, and Helicotylenchus)

J. A. Adediran; A. A. Adegbite; T. A. Akinlosotu; G. O. Agbaje; L. B. Taiwo; O. F. Owolade; G. A. Oluwatosin; Moor Plantation

2005-01-01

352

Plant-parasitic Nematode Problems in the Pacific Islands.  

PubMed

The Pacific islands have a diverse range of food and cash crops with indigenous and introduced nematode problems. The staple food crops have serious nematode pests, such as Meloidogyne spp. on sweet potato, Hirschmanniella miticausa causing corm rot of taro, and Pratylenchus coffeae and Radopholus sp. producing tuber dry rot of yams. Bananas are infested with P. coffeae or R. similis, citrus with Tylenchulus semipenetrans, rice with Aphelenchoides besseyi, and ginger with Meloidogyne spp. and R. similis. Rotylenchulus reniformis, P. zeae, P. brachyurus, and Helicotylenchus spp. are important on all of these and other crops, such as sugarcane, passion fruit, pawpaw, and cassava. Meloidogyne spp. cause serious damage to local and introduced leaf and fruit vegetables and other crops, such as tobacco, sugarcane, pawpaw, black pepper, and pyrethrum. Many other plant-parasitic genera and species, some undescribed, occur in the Pacific, and there are many islands still to be investigated. PMID:19290200

Bridge, J

1988-04-01

353

Underground leaves of Philcoxia trap and digest nematodes  

PubMed Central

The recently described genus Philcoxia comprises three species restricted to well lit and low-nutrient soils in the Brazilian Cerrado. The morphological and habitat similarities of Philcoxia to those of some carnivorous plants, along with recent observations of nematodes over its subterranean leaves, prompted the suggestion that the genus is carnivorous. Here we report compelling evidence of carnivory in Philcoxia of the Plantaginaceae, a family in which no carnivorous members are otherwise known. We also document both a unique capturing strategy for carnivorous plants and a case of a plant that traps and digests nematodes with underground adhesive leaves. Our findings illustrate how much can still be discovered about the origin, distribution, and frequency of the carnivorous syndrome in angiosperms and, more generally, about the diversity of nutrient-acquisition mechanisms that have evolved in plants growing in severely nutrient-impoverished environments such as the Brazilian Cerrado, one of the world's 34 biodiversity hotspots. PMID:22232687

Pereira, Caio G.; Almenara, Daniela P.; Winter, Carlos E.; Fritsch, Peter W.; Lambers, Hans; Oliveira, Rafael S.

2012-01-01

354

Influence of Salinity on Survival and Infectivity of Entomopathogenic: Nematodes  

PubMed Central

Exposure to NaC1, KCI, and CaCl? affected the entomopathogenic nematodes Heterorhabditis bacteriophora and Steinernema glaseri differently. Survival, virulence, and penetration efficiency of S. glaseri were not affected by these salts. At high concentrations, however, all three salts inhibited its ability to move through a soil column and locate and infect a susceptible host. Calcium chloride and KCl had no effect on H. bacteriophora survival, penetration efficiency, or movement through a soil column, but moderate concentrations of these salts enhanced H. bacteriophora virulence. NaCl, however, adversely affected each of these parameters at high salinities (>16 dS/m). Salt effects on S. glaseri are attributed solely to interference with nematode host-finding ability, whereas the NaCl effects on H. bacteriophora are attributed to its toxicity and possibly to interference with host-finding behavior. PMID:19279902

Thurston, Graham S.; Ni, Yansong; Kaya, Harry K.

1994-01-01

355

Noncanonical cell death in the nematode Caenorhabditis elegans  

PubMed Central

The nematode Caenorhabditis. elegans has served as a fruitful setting for cell death research for over three decades. A conserved pathway of four genes, egl-1/BH3-only, ced-9/Bcl-2, ced-4/Apaf-1, and ced-3/caspase, coordinates most developmental cell deaths in C. elegans. However, other cell death forms, programmed and pathological, have also been described in this animal. Some of these share morphological and/or molecular similarities with the canonical apoptotic pathway, while others do not. Indeed, recent studies suggest the existence of an entirely novel mode of programmed developmental cell destruction that may also be conserved beyond nematodes. Here we review evidence for these noncanonical pathways. We propose that different cell death modalities can function as backup mechanisms for apoptosis, or as tailor-made programs that allow specific dying cells to be efficiently cleared from the animal. PMID:25065890

Kinet, Maxime J.; Shaham, Shai

2014-01-01

356

Formation and Regulation of Adaptive Response in Nematode Caenorhabditis elegans  

PubMed Central

All organisms respond to environmental stresses (e.g., heavy metal, heat, UV irradiation, hyperoxia, food limitation, etc.) with coordinated adjustments in order to deal with the consequences and/or injuries caused by the severe stress. The nematode Caenorhabditis elegans often exerts adaptive responses if preconditioned with low concentrations of agents or stressor. In C. elegans, three types of adaptive responses can be formed: hormesis, cross-adaptation, and dietary restriction. Several factors influence the formation of adaptive responses in nematodes, and some mechanisms can explain their response formation. In particular, antioxidation system, heat-shock proteins, metallothioneins, glutathione, signaling transduction, and metabolic signals may play important roles in regulating the formation of adaptive responses. In this paper, we summarize the published evidence demonstrating that several types of adaptive responses have converged in C. elegans and discussed some possible alternative theories explaining the adaptive response control. PMID:22997543

Zhao, Y.-L.; Wang, D.-Y.

2012-01-01

357

WormBase: a comprehensive resource for nematode research  

PubMed Central

WormBase (http://www.wormbase.org) is a central data repository for nematode biology. Initially created as a service to the Caenorhabditis elegans research field, WormBase has evolved into a powerful research tool in its own right. In the past 2 years, we expanded WormBase to include the complete genomic sequence, gene predictions and orthology assignments from a range of related nematodes. This comparative data enrich the C. elegans data with improved gene predictions and a better understanding of gene function. In turn, they bring the wealth of experimental knowledge of C. elegans to other systems of medical and agricultural importance. Here, we describe new species and data types now available at WormBase. In addition, we detail enhancements to our curatorial pipeline and website infrastructure to accommodate new genomes and an extensive user base. PMID:19910365

Harris, Todd W.; Antoshechkin, Igor; Bieri, Tamberlyn; Blasiar, Darin; Chan, Juancarlos; Chen, Wen J.; De La Cruz, Norie; Davis, Paul; Duesbury, Margaret; Fang, Ruihua; Fernandes, Jolene; Han, Michael; Kishore, Ranjana; Lee, Raymond; Müller, Hans-Michael; Nakamura, Cecilia; Ozersky, Philip; Petcherski, Andrei; Rangarajan, Arun; Rogers, Anthony; Schindelman, Gary; Schwarz, Erich M.; Tuli, Mary Ann; Van Auken, Kimberly; Wang, Daniel; Wang, Xiaodong; Williams, Gary; Yook, Karen; Durbin, Richard; Stein, Lincoln D.; Spieth, John; Sternberg, Paul W.

2010-01-01

358

Interactions Between Nematodes and Other Factors on Plants  

PubMed Central

The distinction between qualitative and quantitative interactions is stressed as it helps to elucidate differences between two current definitions of the term synergism and how multifactorial experiments should be designed, analysed statistically, and their results interpreted. Factorial design and analyses are strongly advocated so that interactions can be detected. It is suggested that interactions involving nematodes are common in nature and should be included, where appropriate, in hypotheses. Methods for testing the hypothesis that environment influences tolerance are suggested. PMID:19295795

Wallace, H. R.

1983-01-01

359

Effects of Fixation and Dehydration Procedures on Marine Nematodes  

PubMed Central

Different combinations of fixation and dehydration procedures for the preparation of permanent mounts of marine nematodes of the subfamily Oncholaiminae were tested and compared. Qualitatively, the best specimens resulted from Seinhorst's killing method and fixation in FAA; the dehydration procedure was of less significance. Quantitatively, no significant modification of measurements resulted from any of the methods used. Sources of error in measurements are discussed. PMID:19325668

Timm, R. W.; Hackney, T.

1969-01-01

360

Operons Are a Conserved Feature of Nematode Genomes  

PubMed Central

The organization of genes into operons, clusters of genes that are co-transcribed to produce polycistronic pre-mRNAs, is a trait found in a wide range of eukaryotic groups, including multiple animal phyla. Operons are present in the class Chromadorea, one of the two main nematode classes, but their distribution in the other class, the Enoplea, is not known. We have surveyed the genomes of Trichinella spiralis, Trichuris muris, and Romanomermis culicivorax and identified the first putative operons in members of the Enoplea. Consistent with the mechanism of polycistronic RNA resolution in other nematodes, the mRNAs produced by genes downstream of the first gene in the T. spiralis and T. muris operons are trans-spliced to spliced leader RNAs, and we are able to detect polycistronic RNAs derived from these operons. Importantly, a putative intercistronic region from one of these potential enoplean operons confers polycistronic processing activity when expressed as part of a chimeric operon in Caenorhabditis elegans. We find that T. spiralis genes located in operons have an increased likelihood of having operonic C. elegans homologs. However, operon structure in terms of synteny and gene content is not tightly conserved between the two taxa, consistent with models of operon evolution. We have nevertheless identified putative operons conserved between Enoplea and Chromadorea. Our data suggest that operons and “spliced leader” (SL) trans-splicing predate the radiation of the nematode phylum, an inference which is supported by the phylogenetic profile of proteins known to be involved in nematode SL trans-splicing. PMID:24931407

Pettitt, Jonathan; Philippe, Lucas; Sarkar, Debjani; Johnston, Christopher; Gothe, Henrike Johanna; Massie, Diane; Connolly, Bernadette; Müller, Berndt

2014-01-01

361

Pasteuria penetrans and Its Parasitic Interaction with Plant Parasitic Nematodes  

Microsoft Academic Search

\\u000a The genus Pasteuria comprises a truly extraordinary group of unculturable bacteria that are obligate parasites of either water fleas or plant\\u000a parasitic nematodes. They have an astonishing vegetative morphology that, through an intricate process of differentiation,\\u000a leads to a structurally unique endospore form. Remarkably, phylogenetic studies indicate that this genus is ancestral to the\\u000a genus Bacillus. P.\\u000a penetrans is the

Alistair H. Bishop

362

Nucleoside diphosphate kinase from the parasitic nematode Brugia malayi  

Microsoft Academic Search

Using a reverse transcription-polymerase chain reaction (RT-PCR) procedure that exploited the presence of a conserved 22-nucleotide spliced leader (SL) sequence that is trans-spliced to the 5? end of nematode transcripts, a novel Brugia malayi (Bm) infective-stage SL cDNA expression library was constructed and characterized. The library was immunoscreened with rabbit anti-infective-stage antibodies (Ab) and an immunodominant clone, BmG4–7, was identified

Inca Ghosh; Nithyakalyani Raghavan; Peter C. Fitzgerald; Alan L. Scott

1995-01-01

363

Control of Larval Northern Corn Rootworm. (Diabrotica barberi) with Two Steinernematid Nematode Species  

PubMed Central

The entomogenous nematodes Steinerema feltiae and S. bibionis did not penetrate the roots of corn, Zea mays, to infect larval northern corn rootworm (NCR), Diabrotica barberi, feeding within. Laboratory bioassays against first instar NCR indicated that S. feltiae, Mexican strain (LD?? = 49 nematodes/insect) is more virulent than S. bibionis (LD?? = 100). Numbers of NCR larvae in a grain corn crop were reduced by both nematode species applied at corn seeding time at the rate of 10,000 infective-stage juveniles per linear meter of corn row. The chemical insecticide fonofos provided significantly better control than either nematode species. PMID:19287699

Thurston, G. S.; Yule, W. N.

1990-01-01

364

Nematodes Infect, But Do Not Manipulate Digging By, Sand Crabs, Lepidopa benedicti  

PubMed Central

We examined sand crabs (Lepidopa benedicti) for endoparasites, and found the only parasite consistently infecting the studied population were small nematodes. Because many nematodes have complex life cycles involving multiple hosts, often strongly manipulating their hosts, we hypothesized that nematodes alter the behavior of their sand crab hosts. We predicted that more heavily infected crabs would spend more time above sand than less heavily infected crabs. Our data indicate infection by nematodes was not correlated with duration of time crabs spent above sand. We also suggest that organisms living in sandy beaches may benefit from relatively low parasite loads due to the low diversity of species in the habitat. PMID:24916475

Joseph, Meera; Faulkes, Zen

2014-01-01

365

Effect of Crotalaria juncea Amendment on Nematode Communities in Soil with Different Agricultural Histories  

PubMed Central

Effect of sunn hemp (Crotalaria juncea) hay amendment on nematode community structure in the soil surrounding roots of yellow squash (Cucurbita pepo) infected with root-knot nematodes was examined in two greenhouse experiments. Soils were from field plots treated long-term (LT) with yard-waste compost or no yard-waste compost in LT experiment, and from a short-term (ST) agricultural site in ST experiment. Soils collected were either amended or not amended with C. juncea hay. Nematode communities were examined 2 months after squash was inoculated with Meloidogyne incognita. Amendment increased (P < 0.05) omnivorous nematodes in both experiments but increased only bacterivorous nematodes in ST experiment (P < 0.05), where the soil had relatively low organic matter (<2%). This effect of C. juncea amendment did not occur in LT experiment, in which bacterivores were already abundant. Fungivorous nematodes were not increased by C. juncea amendment in either experiment, but predatory nematodes were increased when present. Although most nematode faunal indices, including enrichment index, structure index, and channel index, were not affected by C. juncea amendment, structure index values were affected by previous soil organic matter content. Results illustrate the importance of considering soil history (organic matter, nutrient level, free-living nematode number) in anticipating changes following amendment with C. juncea hay. PMID:19262764

Wang, K.-H.; McSorley, R.; Gallaher, R. N.

2003-01-01

366

Sensitivity of Nematode Life-History Groups to Ions and Osmotic Tensions of Nitrogenous Solutions  

PubMed Central

Guild designation of nematodes of similar trophic function and life-history strategy provides a basis for using nematode faunal analyses in an integrative assessment of soil food web condition. Omnivorous and predaceous nematodes, categorized at the upper end of a colonizer-persister (c-p) continuum of nematode functional guilds are generally not abundant in cropped soil. These nematodes are more sensitive to heavy metal concentrations than those in other c-p groups, but whether sensitivity to agrochemicals contributes to the observed low abundance of high c-p groups in cropped soils is less well understood. An exposure assay in solution was used to compare the sensitivity of nematodes representing various guilds obtained from field soils and from laboratory culture to several nitrogen sources. Nematodes in c-p groups 4 and 5 were more sensitive to nitrogen solutions than nematodes representing lower c-p groups. There were both osmotic and specific ion effects—the latter most evident in exposure of nematodes to NaNO? and (NH?)?SO?. The RC?? (concentration resulting in nematode recovery of one half of that of distilled water) for (NH?)?SO? was < 0.052 M-N for c-p groups 4 and 5 compared to much greater values (0.34 to 0.81 M-N) for c-p groups 1 to 3. In non-ionic polyethylene glycol (PEG) solutions, osmotic tensions of 0.40 to 0.43 MPa reduced the recovery of exposed nematodes by half (RT??; water potential of solution resulting in nematode recovery of one half of that of distilled water) for c-p groups 4 and 5 compared to > 1.93 MPa for c-p groups 1 to 3. RT?? values for urea solutions, also non-ionic, were greater than for PEG. Caenorhabditis elegans N2 (c-p 1) and Meloidogyne javanica (c-p 3) reared on solid medium and in hydroponic culture, respectively, were slightly more sensitive to specific ion and osmotic effects than nematodes of similar c-p groups obtained from soil. The greater sensitivity of c-p 4 and 5 nematodes to nitrogen solutions suggests that fertilizers may contribute to the low abundance of these nematodes in annual cropping systems. This study supports the use of nematode faunal analyses as indicators of chemical stress in soil. PMID:19262791

Tenuta, Mario; Ferris, Howard

2004-01-01

367

Nutritional sensitivity of periparturient breakdown of immunity to gastrointestinal nematode parasites in mammals   

E-print Network

Mammals usually develop immunity to gastrointestinal nematode parasites. However, during late pregnancy and lactation, this immunity often breaks down, resulting in elevated levels of parasitism. This periparturient ...

Sakkas, Panagiotis

2012-06-22

368

Control of Root-knot Nematodes on Tomato in Stone Wool Substrate with Biological Nematicides  

PubMed Central

The efficacy of four biological nematicides on root-galling, root-knot nematode (Meloidogyne incognita) reproduction, and shoot weight of tomato (Solanum lycopersicum) grown in stone wool substrate or in pots with sandy soil was compared to an oxamyl treatment and a non-treated control. In stone wool grown tomato, Avid® (a.i. abamectin) was highly effective when applied as a drench at time of nematode inoculation. It strongly reduced root-galling and nematode reproduction, and prevented a reduction in tomato shoot weight. However, applying the product one week before, or two weeks after nematode inoculation was largely ineffective. This shows that Avid® has short-lived, non-systemic activity. The effects of Avid® on nematode symptoms and reproduction on soil-grown tomato were only very minor, probably due to the known strong adsorption of the active ingredient abamectin to soil particles. The neem derived product Ornazin® strongly reduced tomato root-galling and nematode reproduction only in stone wool and only when applied as a drench one week prior to nematode inoculation, suggesting a local systemic activity or modification of the root system, rendering them less suitable host for the nematodes. This application however also had some phytotoxic effect, reducing tomato shoot weights. The other two products, Nema-Q™ and DiTera®, did not result in strong or consistent effects on nematode symptoms or reproduction. PMID:22791920

López-Pérez, Jose Antonio; Edwards, Scott

2011-01-01

369

Nematode-Bacterium Symbioses - Cooperation and Conflict Revealed in the 'Omics' Age  

PubMed Central

Nematodes are ubiquitous organisms that have a significant global impact on ecosystems, economies, agriculture, and human health. The applied importance of nematodes and the experimental tractability of many species have promoted their use as models in various research areas, including developmental biology, evolutionary biology, ecology, and animal-bacterium interactions. Nematodes are particularly well suited for investigating host associations with bacteria because all nematodes have interacted with bacteria during their evolutionary history and engage in a diversity of association types. Interactions between nematodes and bacteria can be positive (mutualistic) or negative (pathogenic/parasitic) and may be transient or stably maintained (symbiotic). Furthermore, since many mechanistic aspects of nematode-bacterium interactions are conserved their study can provide broader insights into other types of associations, including those relevant to human diseases. Recently, genome-scale studies have been applied to diverse nematode-bacterial interactions, and have helped reveal mechanisms of communication and exchange between the associated partners. In addition to providing specific information about the system under investigation, these studies also have helped inform our understanding of genome evolution, mutualism, and innate immunity. In this review we will discuss the importance and diversity of nematodes, 'omics' studies in nematode-bacterial systems, and the wider implications of the findings. PMID:22983035

Murfin, Kristen E.; Dillman, Adler R.; Foster, Jeremy M.; Bulgheresi, Silvia; Slatko, Barton E.; Sternberg, Paul W.; Goodrich-Blair, Heidi

2012-01-01

370

Recent advances in our knowledge of Australian anisakid nematodes  

PubMed Central

Anisakidosis is an emerging infection associated with a wide range of clinical syndromes in humans caused by members of the family Anisakidae. Anisakid nematodes have a cosmopolitan distribution and infect a wide range of invertebrates and vertebrates during their life cycles. Since the first report of these parasites in humans during the early 60s, anisakid nematodes have attracted considerable attention as emerging zoonotic parasites. Along with rapid development of various molecular techniques during last several decades, this has caused a significant change in the taxonomy and systematics of these parasites. However, there are still huge gaps in our knowledge on various aspects of the biology and ecology of anisakid nematodes in Australia. Although the use of advanced morphological and molecular techniques to study anisakids had a late start in Australia, great biodiversity was found and unique species were discovered. Here an updated list of members within the family and the current state of knowledge on Australian anisakids will be provided. Given that the employment of advanced techniques to study these important emerging zoonotic parasites in Australia is recent, further research is needed to understand the ecology and biology of these socio economically important parasites. After a recent human case of anisakidosis in Australia, such understanding is crucial if control and preventive strategies are to be established in this country. PMID:25180162

Shamsi, Shokoofeh

2014-01-01

371

Carbohydrate-recognition domains on the surface of phytophagous nematodes.  

PubMed

Human red blood cells (HRBC) adhered to preparasitic second-stage juveniles (J2) of Heterodera avenae, Heterodera schachtii, Meloidogyne javanica, Pratylenchus mediterraneus, Rotylenchulus reniformis, and Tylenchulus semipenetrans over the entire nematode body. Binding was conspicuously confined to the head and tail of Longidorus cohni, Xiphinema brevicolle, and Xiphinema index. Binding was Ca2+ and Mg2+ dependent. In contrast, HRBC did not adhere to Anguina tritici, Aphelenchoides subtenius, Ditylenchus dipsaci, M. javanica females, and Panagrellus redivivus, even in the presence of these cations. Incubation of M. javanica J2 with fucose, glucose, N-acetylglucosamine, mannose, or trypsin decreased the intensity of subsequent HRBC binding, while galactose and N-acetylgalactosamine increased binding intensity. HRBC binding was diminished when nematodes were pretreated with trypsin and eliminated when pretreatments with detergents removed the surface coat. HRBC adhered to nylon fibers coated with surface coat extracted from M. javanica J2; binding was Ca2+ and Mg2+ dependent and diminished when the nylon fibers were coated with bovine serum albumin or preincubated with fucose and mannose. These results demonstrate that HRBC adhesion involves carbohydrate moieties of HRBC and corresponding carbohydrate-recognition domains (CRD) distributed in the nematode surface coat. To our knowledge this is the first report of a surface CRD in the phylum Nematoda. PMID:7895833

Spiegel, Y; Inbar, J; Kahane, I; Sharon, E

1995-03-01

372

A Trichodorus (Triplonchida: Trichodoridae) Nematode from Thrips (Thysanoptera: Panchaetothripinae)  

PubMed Central

A thrips insect Caliothrips sp. (Thysanoptera: Panchaetothripinae) from persimmon fruit (Ebenaceae: Diospyros sp.) from an unknown origin, possibly Asia, was intercepted in a passenger bag in November 2012 at the Peace Arch Border Crossing from Canada to Blaine, WA, by a USDA-APHIS-PPQ port inspector. Nematodes were attached to the abdomen of the female insect and sent to us in saline. Seven nematodes (five females, two males) were measured and these and others were processed for permanent slides. An adult female and a female juvenile were prepared for PCR. Morphologically these nematodes belonged to the Trichodorus sparsus group, and the 28S rDNA D2-D3 sequence showed greatest similarity to Trichodorus paragiennensis (94%) and T. giennensis (93%), with greatest morphological similarity to the latter species. Among other morphological differences, the innermost uterus width is wider than in related species. Trichodorus spp. are normally found in soil, so this is the first population seen in the atypical habitat of an insect. Morphological and molecular characteristics of Trichodorus sp. are presented, but a putative new species name is not currently advisable because of relatively poor condition of specimens. Ecological associations are also discussed. PMID:25276005

Carta, L. K.; Skantar, A. M.

2014-01-01

373

Natural variation of outcrossing in the hermaphroditic nematode Pristionchus pacificus  

PubMed Central

Background Evolution of selfing can be associated with an increase in fixation of deleterious mutations, which in certain conditions can lead to species extinction. In nematodes, a few species evolved self-fertilization independently, making them excellent model systems to study the evolutionary consequences of this type of mating system. Results Here we determine various parameters that influence outcrossing in the hermaphroditic nematode Pristionchus pacificus and compare them to the better known Caenorhabditis elegans. These nematode species are distinct in terms of genetic diversity, which could be explained by differences in outcrossing rates. We find that, similarly to C. elegans, P. pacificus males are generated at low frequencies from self-fertilizing hermaphrodites and are relatively poor mating partners. Furthermore, crosses between different isolates reveal that hybrids have lower brood sizes than the pure strains, which is a sign of outbreeding depression. In contrast to C. elegans, P. pacificus has lower brood sizes and the male X-bearing sperm is able to outcompete the X-nullo sperm. Conclusion The results indicate that there is no evidence of any selection acting very strongly on P. pacificus males. PMID:19379507

Click, Arielle; Savaliya, Chandni H; Kienle, Simone; Herrmann, Matthias; Pires-daSilva, Andre

2009-01-01

374

Bacterial parasite of a plant nematode: morphology and ultrastructure.  

PubMed

The life cycle of a bacterial endoparasite of the plant-parasitic nematode Meloidogyne incognita was examined by scanning and transmission electron microscopy. The infective stage begins with the attachment of an endospore to the surface of the nematode. A germ tube then penetrates the cuticle, and mycelil colonies form in the pseudocoelom. Sporulation is initiated when terminal cells of the mycelium enlarge to form sporangia. A septum within each sporangium divides the forespore from the basal or parasporal portion of the cell. The forespore becomes enclosed by several laminar coats. The parasporal cell remains attached to the forespore and forms the parasporal microfibers. After the newly formed spores are released into the soil, these microfibers apparently enable a mature spore to attach to the nematode. These results indicate that the endoparasite is a procaryotic organism having structural features that are more common to members of Actinomycetales and to the bacterium Pasteuria ramosa than to the sporozoans or to the family Bacillaceae, as previous investigatios have concluded. PMID:838678

Sayre, R M; Wergin, W P

1977-02-01

375

Bioinformatic prediction of arthropod/nematode-like peptides in non-arthropod, non-nematode members of the Ecdysozoa.  

PubMed

The Onychophora, Priapulida and Tardigrada, along with the Arthropoda, Nematoda and several other small phyla, form the superphylum Ecdysozoa. Numerous peptidomic studies have been undertaken for both the arthropods and nematodes, resulting in the identification of many peptides from each group. In contrast, little is known about the peptides used as paracrines/hormones by species from the other ecdysozoan taxa. Here, transcriptome mining and bioinformatic peptide prediction were used to identify peptides in members of the Onychophora, Priapulida and Tardigrada, the only non-arthropod, non-nematode members of the Ecdysozoa for which there are publicly accessible expressed sequence tags (ESTs). The extant ESTs for each phylum were queried using 106 arthropod/nematode peptide precursors. Transcripts encoding calcitonin-like diuretic hormone and pigment-dispersing hormone (PDH) were identified for the onychophoran Peripatopsis sedgwicki, with transcripts encoding C-type allatostatin (C-AST) and FMRFamide-like peptide identified for the priapulid Priapulus caudatus. For the Tardigrada, transcripts encoding members of the A-type allatostatin, C-AST, insect kinin, orcokinin, PDH and tachykinin-related peptide families were identified, all but one from Hypsibius dujardini (the exception being a Milnesium tardigradum orcokinin-encoding transcript). The proteins deduced from these ESTs resulted in the prediction of 48 novel peptides, six onychophoran, eight priapulid and 34 tardigrade, which are the first described from these phyla. PMID:21074533

Christie, Andrew E; Nolan, Daniel H; Garcia, Zachery A; McCoole, Matthew D; Harmon, Sarah M; Congdon-Jones, Benjamin; Ohno, Paul; Hartline, Niko; Congdon, Clare Bates; Baer, Kevin N; Lenz, Petra H

2011-02-01

376

Nematode community structure along a central Chile margin transect influenced by the oxygen minimum zone  

NASA Astrophysics Data System (ADS)

Nematodes are among the metazoans most tolerant of low-oxygen conditions and play major roles in seafloor ecosystem processes. Nematode communities were studied in sediments off Concepción, Central Chile, spanning the outer shelf within the OMZ (122 m) to the mid-lower continental slope (972 m) beneath the OMZ. The total density and biomass of nematodes (core depth 0-10 cm) ranged from 677 to 2006 ind. 10 cm-2, and 168.4 to 506.5 ?g DW 10 cm-2, respectively. Among metazoan meiofaunal taxa, nematodes predominated at all sites both in terms of relative abundance (83.7-99.4%) and biomass (53.8-88.1%), followed by copepods, nauplii and polychaetes. Nematodes were represented by 33 genera distributed among 17 families, with densities greatest at low oxygen sites (122-364 m; ~2000 ind. 10 cm-2). Nematode generic and trophic diversity, and individual biomass were lowest, and Rank 1 dominance was highest, at the most oxygen-depleted site (122 m), despite the fact that the organic carbon content of the sediment was maximal at this depth. At the most oxygenated slope sites (827 and 972 m), all of Wieser's nematode feeding groups were represented. In contrast, at the lowest-oxygen site, only selective deposit (bacterial) feeders (1A) were present, indicating a reduction in trophic complexity. A large percentage of nematodes inhabited subsurface sediment layers (>1 cm). At deeper, more oxygenated sites (827 and 972 m), nematode individual biomass increased downcore, while within the OMZ, nematode biomass was low and remained relatively uniform through the sediment column. The concentration of nematodes in deeper sediment layers, the vertical distribution of the feeding groups, as well as the high nutritional quality of the deeper layers, suggest a differential resource partitioning of the food available, which may reduce interspecific competition.

Neira, Carlos; King, Ian; Mendoza, Guillermo; Sellanes, Javier; De Ley, Paul; Levin, Lisa A.

2013-08-01

377

Soil nematode assemblages as bioindicators of radiation impact in the Chernobyl Exclusion Zone.  

PubMed

In radioecology, the need to understand the long-term ecological effects of radioactive contamination has been emphasised. This requires that the health of field populations is evaluated and linked to an accurate estimate of received radiological dose. The aim of the present study was to assess the effects of current radioactive contamination on nematode assemblages at sites affected by the fallout from the Chernobyl accident. First, we estimated the total dose rates (TDRs) absorbed by nematodes, from measured current soil activity concentrations, Dose Conversion Coefficients (DCCs, calculated using EDEN software) and soil-to-biota concentration ratios (from the ERICA tool database). The impact of current TDRs on nematode assemblages was then evaluated. Nematodes were collected in spring 2011 from 18 forest sites in the Chernobyl Exclusion Zone (CEZ) with external gamma dose rates, measured using radiophotoluminescent dosimeters, varying from 0.2 to 22 ?Gy h(-1). These values were one order of magnitude below the TDRs. A majority of bacterial-, plant-, and fungal-feeding nematodes and very few of the disturbance sensitive families were identified. No statistically significant association was observed between TDR values and nematode total abundance or the Shannon diversity index (H'). The Nematode Channel Ratio (which defines the relative abundance of bacterial- versus fungal-feeding nematodes) decreased significantly with increasing TDR, suggesting that radioactive contamination may influence nematode assemblages either directly or indirectly by modifying their food resources. A greater Maturity Index (MI), usually characterising better soil quality, was associated with higher pH and TDR values. These results suggest that in the CEZ, nematode assemblages from the forest sites were slightly impacted by chronic exposure at a predicted TDR of 200 ?Gy h(-1). This may be imputable to a dominant proportion of pollutant resistant nematodes in all sites. This might result from a selection at the expense of sensitive species after the accident. PMID:24852614

Lecomte-Pradines, C; Bonzom, J-M; Della-Vedova, C; Beaugelin-Seiller, K; Villenave, C; Gaschak, S; Coppin, F; Dubourg, N; Maksimenko, A; Adam-Guillermin, C; Garnier-Laplace, J

2014-08-15

378

Molecular Diversity of Fungal Phylotypes Co-Amplified Alongside Nematodes from Coastal and Deep-Sea Marine Environments  

Microsoft Academic Search

Nematodes and fungi are both ubiquitous in marine environments, yet few studies have investigated relationships between these two groups. Microbial species share many well-documented interactions with both free-living and parasitic nematode species, and limited data from previous studies have suggested ecological associations between fungi and nematodes in benthic marine habitats. This study aimed to further document the taxonomy and distribution

Punyasloke Bhadury; Holly Bik; John D. Lambshead; Melanie C. Austen; Gary R. Smerdon; Alex D. Rogers

2011-01-01

379

A Phosphopantetheinyl Transferase Homolog Is Essential for Photorhabdus luminescens To Support Growth and Reproduction of the Entomopathogenic Nematode Heterorhabditis bacteriophora  

Microsoft Academic Search

The bacterium Photorhabdus luminescens is a symbiont of the entomopathogenic nematode Heterorhabditis bacteriophora. The nematode requires the bacterium for infection of insect larvae and as a substrate for growth and reproduction. The nematodes do not grow and reproduce in insect hosts or on artificial media in the absence of viable P. luminescens cells. In an effort to identify bacterial factors

TODD A. CICHE; SCOTT B. BINTRIM; ALEXANDER R. HORSWILL; JERALD C. ENSIGN

2001-01-01

380

Directional movement of entomopathogenic nematodes in response to electrical field: effects of species, magnitude of voltage, and infective juvenile age  

Microsoft Academic Search

Entomopathogenic nematodes respond to a variety of stimuli when foraging. Previously, we reported a directional response to electrical fields for two entomopathogenic nematode species; specifically, when electrical fields were generated on agar plates Steinernema glaseri (a nematode that utilizes a cruiser-type foraging strategy) moved to a higher electric potential, whereas Steinernema carpocapsae, an ambush-type forager, moved to a lower potential.

David I. Shapiro-Ilan; Edwin E. Lewis; James F. Campbell; Daniel B. Kim-Shapiro

381

Effect of soil moisture and a surfactant on entomopathogenic nematode suppression of the pecan weevil, Curculio caryae  

Technology Transfer Automated Retrieval System (TEKTRAN)

Our overall goal was to investigate several aspects of Curculio caryae suppression using entomopathogenic nematodes. Our results indicated no effect of a surfactant (Kinetic) on C. caryae suppression with entomopathogenic nematodes. Nematode efficacy was tested in a loamy sand at negative 0.01, 0....

382

THE VALUE OF THE USDA NEMATODE COLLECTION AND ITS DATABASE FOR TAXONOMIC AND SYSTEMATIC RESEARCH  

Technology Transfer Automated Retrieval System (TEKTRAN)

The United States Department of Agriculture Nematode Collection (USDANC) at Beltsville, Maryland, is one of the largest and most valuable international resources for nematode taxonomic research and identifications. It is widely used by scientists throughout the world to resolve various taxonomic an...

383

Processed Biosolids: Unwanted Wastes or Products for Soybean Cyst Nematode Control  

Technology Transfer Automated Retrieval System (TEKTRAN)

The concept of utilizing waste products (e.g., manure, plants residues, and industrial by-products) to manage plant-parasitic nematodes is not new, but the widespread implementation of this management practice has still not been realized. The use of waste products for plant-parasitic nematode manag...

384

Response of a nematode community to tillage and nematicide application in cotton  

Technology Transfer Automated Retrieval System (TEKTRAN)

We hypothesized that tillage and nematicide use would reduce the relative abundance of predatory and omnivorous nematodes, which in turn would result in greater survival and reproductive potential of plant-parasitic nematodes later in the season. To test this two-part hypothesis, we conducted a spl...

385

A survey of plant-parasitic nematodes associated with forage crops in Bingol, Turkey  

Technology Transfer Automated Retrieval System (TEKTRAN)

During June 2011, a survey was conducted in four districts of Bingol Province, Turkey, to investigate the occurrence, population abundance and spatial distribution of plant-parasitic nematodes associated with pastures. A total of 24 soil samples were collected. Nematodes were extracted from soil by ...

386

Observations on the foliar nematode, Aphelenchoides besseyi, infecting tuberose and rice in India  

Technology Transfer Automated Retrieval System (TEKTRAN)

The foliar nematode Aphelenchoides besseyi causes white tip disease in rice (Oryza sativa L.) and floral malady in tuberose (Polianthes tuberosa L.). This nematode is widely distributed in the rice fields of many states of India, including West Bengal (WB), Andhra Pradesh (AP), Madhya Pradesh (MP) a...

387

Complete Genome Sequence of Le Blanc Virus, a Third Caenorhabditis Nematode-Infecting Virus  

E-print Network

Complete Genome Sequence of Le Blanc Virus, a Third Caenorhabditis Nematode-Infecting Virus Carl J,a and Institute of Biology of the Ecole Normale Supérieure (IBENS), Paris, Franceb Orsay virus and Santeuil virus, the first known viruses capable of naturally infecting the nematodes Caenorhabditis elegans

Wang, David

388

Ammonia concentration at emergence and its effects on the recovery of different species of entomopathogenic nematodes.  

PubMed

The life cycle of entomopathogenic nematodes (EPN) occurs inside an insect cadaver and an accumulation of ammonia initiates as a consequence of the nematodes defecation. This accumulation reduces the food resources quality and creates a detrimental environment for nematodes. When a given ammonia concentration is reached, the nematodes start their emergence process, searching for a new host. In the present work, this parameter, ammonia triggering point (ATP) was measured in 7 Steinernema species/strains. The effect of different ammonia concentrations on the recovery process and their consequences in the nematodes survival were also investigated. The results indicate that ATP varies among nematode species; Steinernema glaseri showed the highest ATP of the evaluated species (1.98±2.6 mg of NH4-N*g of Galleria mellonella(-1)); whereas Steinernema riobrave presented the lowest ATP (1.16±0.1 mg of NH4-N*g of G. mellonella(-1)). On the other hand, the nematode emergence could be a repulsive response when ATP is reached. As the ammonia concentration increased the recovery percentage of Steinernema feltiae (Chile strain) dropped gradually from 79.4±11.9% in the control treatment to 0% when 1mg of NH4-N*ml of bacterial broth(-1) was added. It is possible, that emergence process could be a repulsive response of the nematodes due to ammonia concentration when is reaching the ATP. The role of ammonia inside the insect cadavers, might suggests connections with some stages of the EPN life cycle. PMID:24880156

San-Blas, Ernesto; Pirela, Deynireth; García, Dana; Portillo, Edgar

2014-09-01

389

FIRST REPORT OF THE PALE CYST NEMATODE (GLOBODERA PALLIDA) IN THE UNITED STATES  

Technology Transfer Automated Retrieval System (TEKTRAN)

In 2006, a cyst nematode was discovered in tare dirt at a potato processing facility in eastern Idaho. The nematode was found during a routine survey conducted jointly by the Idaho State Department of Agriculture and the USDA Animal and Plant Health Inspection Service through the Cooperative Agricul...

390

PA-560, A Southern Root-knot Nematode Resistant, Yellow-fruited, Habanero-type Pepper  

Technology Transfer Automated Retrieval System (TEKTRAN)

The USDA has developed a yellow-fruited, Habanero-type pepper (Capsicum chinense Jacq.) that is highly resistant to root-knot nematodes. The new breeding line, designated PA-560, is the product of a backcross/pedigree breeding procedure to incorporate a root-knot nematode resistance gene from the S...

391

Poultry litter compost for suppression of root-knot nematode on cacao plants  

Technology Transfer Automated Retrieval System (TEKTRAN)

Root-knot nematodes (Meloidogyne spp.; RKN) are economically the most important nematodes that attack cacao (Theobroma cacao L.) plants worldwide. Poultry litter (poultry manure mixed with the wood shavings that are used for bedding or for covering the soil floor in poultry housing units) compost w...

392

Some taxonomic and phylogenetic trends for free-living and plant-parasitic nematodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

The information, techniques and strategies used by nematode taxonomists have improved in major ways over the last 15 years. New methods of specimen preparation, new microscopic procedures, and new morphological and molecular characters have improved the quality of nematode descriptions. Testing taxo...

393

DIBOA: Fate in Soil and Effects on Root-knot Nematode Egg Numbers  

Technology Transfer Automated Retrieval System (TEKTRAN)

The benzoxazinoid 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) is produced by rye (Secale cereale) and may contribute to plant-parasitic nematode suppression when rye plants are incorporated as a green manure. We investigated the fate of DIBOA in soil and DIBOA’s effects on nematode reproduction. Soil...

394

QTLs associated with resistance in soybean PI567516C to synthetic nematode population infecting cv. Hartwig  

Technology Transfer Automated Retrieval System (TEKTRAN)

Worldwide, soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most destructive pathogen of soybean [Glycine max (L.) Merr.]. Crop losses are primarily mitigated by the use of resistant cultivars. Nematode populations are variable and have adapted to reproduce on resistant cultivars ov...

395

Patterns of sensitivity to cadmium and pentachlorophenol among nematode species from different taxonomic and ecological groups  

Microsoft Academic Search

The variation of acute toxicity data among nematode species belonging to different taxonomic and ecological groups was investigated. Twelve different nematode species were extracted from the soil and directly exposed to cadmium and pentachlorophenol. LC50-values were estimated after 24, 48, 72, and 96 h of exposure in aqueous solutions. The species exhibited large differences in sensitivity. LC50-values (72 h) for

J. E. Kammenga; C. A. M. Van Gestel; J. Bakker

1994-01-01

396

THE ORDINATION OF AQUATIC NEMATODE COMMUNITIES AS AFFECTED BY STREAM WATER QUALITY  

EPA Science Inventory

Benthic nematodes were sampled at 16 sites on two streams to investigate the relationships of nematode community structure to various water quality factors. A prominence value for each species was calculated for use in three-dimensional community ordination. Species composition o...

397

Population changes of nematodes associated with Citrus reticulata and Citrus aurantifolia  

Microsoft Academic Search

Two economically important species of Citrus fruits viz., orange, Citrus reliculata and lemon, C. aurantifolia were selected for studying the changes in the population of plant parasitic nematodes around their roots. The nematode population of Hoplolaimus indicus, Helicotylenchus indicus, Xiphinema americanum, Pratylenchus coffeae, Tylenchulus semipenetrans and Hemicriconemoides mangiferae was observed at 10?cm (upper layer) followed by 20?cm (middle) and 40?cm

Mansoor A Siddiqui

2005-01-01

398

SURVEY OF LESION AND NORTHERN ROOT-KNOT NEMATODES ASSOCIATED WITH VEGETABLES IN VERMONT  

E-print Network

98 SURVEY OF LESION AND NORTHERN ROOT-KNOT NEMATODES ASSOCIATED WITH VEGETABLES IN VERMONT Yong Bao, Burlington, 05405. *Corresponding author: ybao@uvm.edu ABSTRACT Bao, Yong, and Deborah A. Neher. 2011. Survey, no formal statewide nematode survey has been conducted. A survey was conducted to determine the frequency

Neher, Deborah A.

399

Nematode and grape rootstock interactions including an improved understanding of tolerance.  

PubMed

Sixteen cultivars of grape were screened over a two-year period in the presence or absence of 10 different nematode populations. Populations of Meloidogyne spp., Xiphinema index, and Mesocriconema xenoplax developed more rapidly and caused greater damage than populations of X. americanum and Tylenchulus semipenetrans. Populations of mixed Meloidogyne spp. having a history of feeding on grape were among the fastest developing populations. Tolerance to nematode parasitism appeared to be based on different mechanisms. Slow developing, less pathogenic nematode populations often stimulated vine growth, thus vines appeared to possess tolerance. Likewise, cultivars selected for nematode resistance often stimulated vine growth when fed upon by the nematode. However, tolerance sources that resulted from nematode resistance are vulnerable due to the occurrence of populations that break resistance mechanisms. Growth of cultivars with phylloxera (Daktalospharia vitifoliae) resistance was unchanged by the presence of nematodes, indicating that phylloxera resistance may provide a useful source of nematode relief. These and several additional sources of specific tolerance are discussed. PMID:19259534

McKenry, M V; Anwar, Safdar A

2006-09-01

400

The Potential for Mapping Nematode Distributions for Site-specific Management  

PubMed Central

The success of site-specific nematode management depends on a grower or advisor being able to afford to make a map of an infestation that is accurate enough for management decisions. The spatial dependence of nematode infestations and correlation of soil attributes with nematode density were assessed to investigate the scale of sampling required to obtain correlated observations of density and the use of soils data to reduce the cost of sampling. Nematodes and soil were sampled on a 76.2 × 76.2-m grid in two irrigated corn (Zea mays) fields for 2 years. Nematodes of each of three species were found in 36% to 77% of the cores from a field. Spatial dependence was detected for 10 of 16 distributions, and 22% to 67% of the variation in density within a field could be attributed to spatial correlation. Density was correlated to distances of 115 to 649 m in the directions of 0, 45, 90, and 135° from the crop row, and distances varied with direction. Correlations between nematode density and soil attributes were inconsistent between species and fields. These results indicate a potential for mapping nematode infestations for site-specific management, but provide no evidence for reducing the cost of sampling by substituting soils data for nematode counts when making a map. PMID:19265913

Wyse-Pester, Dawn Y.; Wiles, Lori J.; Westra, Philip

2002-01-01

401

Nematode and Grape Rootstock Interactions Including an Improved Understanding of Tolerance  

PubMed Central

Sixteen cultivars of grape were screened over a two-year period in the presence or absence of 10 different nematode populations. Populations of Meloidogyne spp., Xiphinema index, and Mesocriconema xenoplax developed more rapidly and caused greater damage than populations of X. americanum and Tylenchulus semipenetrans. Populations of mixed Meloidogyne spp. having a history of feeding on grape were among the fastest developing populations. Tolerance to nematode parasitism appeared to be based on different mechanisms. Slow developing, less pathogenic nematode populations often stimulated vine growth, thus vines appeared to possess tolerance. Likewise, cultivars selected for nematode resistance often stimulated vine growth when fed upon by the nematode. However, tolerance sources that resulted from nematode resistance are vulnerable due to the occurrence of populations that break resistance mechanisms. Growth of cultivars with phylloxera (Daktalospharia vitifoliae) resistance was unchanged by the presence of nematodes, indicating that phylloxera resistance may provide a useful source of nematode relief. These and several additional sources of specific tolerance are discussed. PMID:19259534

McKenry, M.V.; Anwar, Safdar A.

2006-01-01

402

Longevity of insect-killing nematodes in soil from a pecan orchard  

Technology Transfer Automated Retrieval System (TEKTRAN)

Entomopathogenic (insect-killing) nematodes are candidates for use as biological control agents for important pecan insect pests such as the pecan weevil, Curculio caryae. In deciding which kind of nematode (species or strain) is the best one to use, it is important to consider which one is likely t...

403

Impact of a nematicide on biological suppression of plant-parasitic nematodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Application of the fumigant nematicide 1,3-D (Telone) could lead to pest resurgence if populations of predatory nematodes are slower to recover than populations of plant-parasitic nematodes. We sampled soil from control and 1,3-D-treated plots in a replicated field study to determine the effect of ...

404

Genetic Dissection of Resistance in Soybean PI567516C to a Nematode Population Infecting cv. Hartwig  

Technology Transfer Automated Retrieval System (TEKTRAN)

Worldwide, soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most destructive pathogen of soybean [Glycine max (L.) Merr.]. Crop losses are primarily mitigated by the use of resistant cultivars. Nematode populations are variable and have adapted to reproduce on resistant cultivars ov...

405

Inheritance of Resistance in Soybean PI 567516C to LY1 Nematode Population Infecting cv. Hartwig  

Technology Transfer Automated Retrieval System (TEKTRAN)

Worldwide, cyst nematode (SCN: Heterodera glycines Ichinohe) is the most destructive pathogen on soybean [Glycine max (L.) Merr.]. In the USA yield losses in 2001 were estimated to be nearly sixty million dollars. Crop losses are primarily reduced by the use of resistant cultivars. Nematode populat...

406

Detection and Management of Stunt and Stubby-Root Nematodes in a Southern Forest Nursery  

Microsoft Academic Search

Populations of stunt (Tylenchorhynchus claytoni) and stubby-root (Paratrichodorus minor) nematodes, as well as predaceous nematodes (Mylonchulus spp., Mononchus spp.), were monitored in 2005 for 8 months in three loblolly pine fields at a southern forest nursery. The fields were selected based on their 2004 management regimes and consisted of one that was fall fumigated with a combination of 67% methyl

Michelle M. Cram; Stephen W. Fraedrich

407

Effect of nitrogen and phosphate fertilisers on microbial and nematode diversity in pasture soils  

Microsoft Academic Search

Soil microbial and nematode populations, soil microbial community structure, and microbial and nematode functional diversity were studied in two fertiliser trials on perennial pasture at three sampling times. The N trial involved the application of 0, 200 and 400kg N ha?1 y?1 in the form of urea. The P trial involved the application of 0, 30, 50 and 100kg P

S. U Sarathchandra; A Ghani; G. W Yeates; G Burch; N. R Cox

2001-01-01

408

A hyperspectral reflectance data based model inversion methodology to detect reniform nematodes in cotton  

Microsoft Academic Search

Rotylenchulus reniformis is a newly emerging nematode species affecting the cotton crop and quickly spreading throughout the southeastern United States. Effective use of nematicides at a variable rate is the only economic counter measure. It requires the nematode population in the field to be known, which in turn depends on the collection of soil samples from the field and analyzing

Pavan K. Palacharla; Surya S. Durbha; Roger L. King; Balakrishna Gokaraju; Gary W. Lawrence

2011-01-01

409

The maturity index: an ecological measure of environmental disturbance based on nematode species composition  

Microsoft Academic Search

Nematode assemblages constitute a potential instrument for assessing the quality of submersed, temporarily submersed, and terrestrial soils and for the development of an ecological typology and biomonitoring system. Interpretation of physical or pollution-induced disturbances has hitherto mainly been based on changes in diversity, dominance patterns or percentage of dorylaimids (Adenophorea). The maturity index, based on the nematode fauna, is proposed

Tom Bongers

1990-01-01

410

The entomopathogenic nematode Heterorhabditis megidis: host searching behaviour, infectivity and reproduction  

Microsoft Academic Search

Entomopathogenic nematodes in the families Heterorhabditidae and Steinernematidae have considerable potential as biological control agents of soil-inhabiting insect pests. Attributes making these nematodes ideal biological control agents include their broad host range, high virulence, safety to non target organisms, ability to search for hosts, high efficacy in favourable habitats, high reproductive potential, ease of mass production, ease of application, and

M. I. C. Boff

2001-01-01

411

Plant-parasitic nematodes associated with grapevines, Vitis vinifera, in Washington and Idaho  

Technology Transfer Automated Retrieval System (TEKTRAN)

Surveys were conducted in eastern Washington and Idaho to determine the plant-parasitic nematodes associated with wine grape (Vitis vinifera) vineyards. The most commonly encountered plant-parasitic nematodes in eastern Washington and Idaho wine grape vineyards were Meloidogyne hapla, Paratylenchus ...

412

Soil moisture and strain effects on entomopathogenic nematode suppression of the pecan weevil  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Pecan weevil, Curculio caryae, is a key pest of pecan. We report here an update of research activities focused on the suppression and eventual control of pecan weevils with beneficial organisms, specifically entomopathogenic (insect-killing) nematodes. These nematodes only attack insects and a...

413

Sunn Hemp cover cropping and organic fertilizer effects on the nematode community under temperate growing conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plantings of sunn hemp as a cover crop have been experimentally shown to improve soil health, reduce plant-parasitic nematodes, and increase nematode-antagonistic microorganisms. However, these studies have been largely conducted in tropical and subtropical regions. To investigate the impacts of sun...

414

Screening Cowpea Varieties for Reaction to Root-Knot Nematode Under Field Conditions  

Microsoft Academic Search

Insects, weeds, vertebrate pests, nematodes, and diseases are major constraints to the production of cowpea. Conventional nematicides are the most effective way of controlling nematode problems in soils where cowpea is grown. However, due to high cost of nematicides, application hazards and fear of environmental contamination, alternatives such as crop rotation and the use of resistant cultivars are control methods

A. A. Adegbite; N. A. Amusam; G. O. Agbaje; L. B. Taiwo

2006-01-01

415

Root Extracts of Plants to Control Root-Knot Nematode on Edible Soybean  

Microsoft Academic Search

Control of plant-parasitic nematodes essentially involves use of synthetic nematicides. However, apart from cost, increased concern for the environment has necessitated a reduction in the amount of nematicides used for control. Additionally, there has been an increase in the search for other efficient; ecologically sound and safe control methods. Eggs of root-knot nematode, Meloidogyne incognita (Kofoid & White) Chitwood, were

A. A. Adegbite; S. O. Adesiyan

2006-01-01

416

QTLS associated with resistance to soybean cyst nematode: Meta-analysis of QTL locations  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) is the most important pest of soybean (Glycine max (L.) Merr) in the world. A total of 17 quantitative trait locus (QTL) mapping papers and 62 marker-QTL associations have been reported for resistance to soybean cyst nematode in soybean. C...

417

Distribution and infestation rate of cyst nematodes (Tylenchida: Heteroderidae) in cabbage growing areas in Samsun  

Technology Transfer Automated Retrieval System (TEKTRAN)

Information concerning the occurrence and distribution of cyst nematodes (Heterodera spp.) in Samsun, Turkey is needed to assess their potential to cause economic damage on many crop plants. Surveys on the distribution and infestation rates of cyst nematodes in cabbage fields in Samsun were conducte...

418

Outer Ear Canal Infection with Rhabditis sp. Nematodes in a Human  

PubMed Central

Here we report the first human case of an outer ear canal infection with a free-living nematode of the genus Rhabditis. Otomicroscopy revealed viable worms in the outer ear canal of a patient suffering from chronic otorrhea and hearing loss. The nematode was identified by microscopy and internal transcribed spacer (ITS)-PCR. PMID:24599974

Würfel, Waldemar; Sedlacek, Ludwig; Suerbaum, Sebastian; Tappe, Dennis; Hornef, Mathias Walter

2014-01-01

419

Post-transcriptional gene silencing of root knot-nematode in transformed soybean roots  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plant-parasitic nematodes cause about $100 billion in crop losses annually. Root-knot nematodes (RKN; Meloidogyne spp.) are sedentary endoparasites, and the genus has been found on more than 3000 host plant species. In this study four different gene constructs were designed to produce RNA interferen...

420

Field Application of Entomopathogenic Nematodes for Control of Delia radicum in Collards  

PubMed Central

Control of Delia radicum (cabbage maggot) in field collards (Brassica oleracea) was compared after one or two applications of entomopathogenic nematodes, Steinernema carpocapsae (All strain) and Heterorhabditis bacterophora (HP88 strain), a single application of granular chlorpyrifos, and a water-only treatment. Nematodes were applied with a sprayer during the egg stage of first-generation D. radicum, and chlorpyrifos was hand placed around collard stems during the same period. A second nematode application was made 10 days later. Chlorpyrifos treatment resulted in fewer puparia per plant, less root damage and higher yield than all other treatments, including the control. Collard yield from nematode-treated beds did not differ from controls. These data indicate that, under these field conditions, the species or strains of entomopathogenic nematodes tested did not reduce the number of active cabbage maggots, nor did they prevent collard root damage. PMID:19283012

Simser, Dave

1992-01-01

421

Microsporidia Are Natural Intracellular Parasites of the Nematode Caenorhabditis elegans  

PubMed Central

For decades the soil nematode Caenorhabditis elegans has been an important model system for biology, but little is known about its natural ecology. Recently, C. elegans has become the focus of studies of innate immunity and several pathogens have been shown to cause lethal intestinal infections in C. elegans. However none of these pathogens has been shown to invade nematode intestinal cells, and no pathogen has been isolated from wild-caught C. elegans. Here we describe an intracellular pathogen isolated from wild-caught C. elegans that we show is a new species of microsporidia. Microsporidia comprise a large class of eukaryotic intracellular parasites that are medically and agriculturally important, but poorly understood. We show that microsporidian infection of the C. elegans intestine proceeds through distinct stages and is transmitted horizontally. Disruption of a conserved cytoskeletal structure in the intestine called the terminal web correlates with the release of microsporidian spores from infected cells, and appears to be part of a novel mechanism by which intracellular pathogens exit from infected cells. Unlike in bacterial intestinal infections, the p38 MAPK and insulin/insulin-like growth factor (IGF) signaling pathways do not appear to play substantial roles in resistance to microsporidian infection in C. elegans. We found microsporidia in multiple wild-caught isolates of Caenorhabditis nematodes from diverse geographic locations. These results indicate that microsporidia are common parasites of C. elegans in the wild. In addition, the interaction between C. elegans and its natural microsporidian parasites provides a system in which to dissect intracellular intestinal infection in vivo and insight into the diversity of pathogenic mechanisms used by intracellular microbes. PMID:19071962

Troemel, Emily R; Félix, Marie-Anne; Whiteman, Noah K; Barrière, Antoine; Ausubel, Frederick M

2008-01-01

422

Specific Microbial Attachment to Root Knot Nematodes in Suppressive Soil  

PubMed Central

Understanding the interactions of plant-parasitic nematodes with antagonistic soil microbes could provide opportunities for novel crop protection strategies. Three arable soils were investigated for their suppressiveness against the root knot nematode Meloidogyne hapla. For all three soils, M. hapla developed significantly fewer galls, egg masses, and eggs on tomato plants in unsterilized than in sterilized infested soil. Egg numbers were reduced by up to 93%. This suggested suppression by soil microbial communities. The soils significantly differed in the composition of microbial communities and in the suppressiveness to M. hapla. To identify microorganisms interacting with M. hapla in soil, second-stage juveniles (J2) baited in the test soil were cultivation independently analyzed for attached microbes. PCR-denaturing gradient gel electrophoresis of fungal ITS or 16S rRNA genes of bacteria and bacterial groups from nematode and soil samples was performed, and DNA sequences from J2-associated bands were determined. The fingerprints showed many species that were abundant on J2 but not in the surrounding soil, especially in fungal profiles. Fungi associated with J2 from all three soils were related to the genera Davidiella and Rhizophydium, while the genera Eurotium, Ganoderma, and Cylindrocarpon were specific for the most suppressive soil. Among the 20 highly abundant operational taxonomic units of bacteria specific for J2 in suppressive soil, six were closely related to infectious species such as Shigella spp., whereas the most abundant were Malikia spinosa and Rothia amarae, as determined by 16S rRNA amplicon pyrosequencing. In conclusion, a diverse microflora specifically adhered to J2 of M. hapla in soil and presumably affected female fecundity. PMID:24532076

Adam, Mohamed; Westphal, Andreas; Hallmann, Johannes

2014-01-01

423

Generalists at the interface: Nematode transmission between wild and domestic ungulates  

PubMed Central

Many parasitic nematode species are generalists capable of infecting multiple host species. The complex life cycle of nematodes, involving partial development outside of the host, facilitates transmission of these parasites between host species even when there is no direct contact between hosts. Infective nematode larvae persist in the environment, and where grazing or water sources are shared ingestion of parasite larvae deposited by different host species is likely. In this paper we examine the extent to which nematode parasite species have been observed in sympatric wild and domestic ungulates. First, using existing host–parasite databases, we describe expected overlap of 412 nematode species between 76 wild and 8 domestic ungulate host species. Our results indicate that host-specific parasites make up less than half of the nematode parasites infecting any particular ungulate host species. For wild host species, between 14% (for common warthog) and 76% (for mouflon) of parasitic nematode species are shared with domestic species. For domestic host species, between 42% (for horse) and 77% (for llamas/alpacas) of parasitic nematode species are shared with wild species. We also present an index of liability to describe the risk of cross-boundary parasites to each host species. We then examine specific examples from the literature in which transmission of nematode parasites between domestic and wild ungulates is described. However, there are many limitations in the existing data due to geographical bias and certain host species being studied more frequently than others. Although we demonstrate that many species of parasitic nematode are found in both wild and domestic hosts, little work has been done to demonstrate whether transmission is occurring between species or whether similar strains circulate separately. Additional research on cross-species transmission, including the use of models and of genetic methods to define strains, will provide evidence to answer this question. PMID:25426420

Walker, Josephine G.; Morgan, Eric R.

2014-01-01

424

Short-term effects of forest disturbances on soil nematode communities in European mountain spruce forests.  

PubMed

The nematode communities in spruce forests were compared with the short-term effects of forest damage, caused by windstorm, wildfire and management practices of forest soils. Soil samples were collected in June and October from 2006 to 2008 in four different sites: (1) forest unaffected by the wind (REF); (2) storm-felled forest with salvaged timber (EXT); (3) modified forest affected by timber salvage (wood removal) and forest fire (FIR); and (4) storm-felled forest where timber had been left unsalvaged (NEX). Nematode analysis showed that the dominant species in all four investigated sites were Acrobeloides nanus and Eudorylaimus silvaticus. An increase of A. nanus (35% of the total nematode abundance) in the first year in the FIR site led to the highest total abundance of nematodes compared with other sites, where nematode abundance reached the same level in the third year. In the FIR site bacterial feeders appeared to be the most representative trophic group, although in the second and third year, after disturbance, the abundance of this trophic group gradually decreased. In the NEX site, the number of nematode species, population densities and Maturity Index were similar to that recorded for the FIR site. In EXT and NEX sites, the other dominant species was the plant parasitic nematode Paratylenchus microdorus. Analyses of nematodes extracted from different forest soil samples showed that the highest number of species and diversity index for species (H'spp) were in the REF site. Differences between the nematode fauna in REF and other localities were clearly depicted by cluster analysis. The greatest Structure Index and Enrichment Index values were also in REF. In the EXT site, the number of nematode species, their abundance, H'spp and Maturity Index were not significantly different from those recorded in the reference site. PMID:23046609

?erevková, A; Ren?o, M; Cagá?, L

2013-09-01

425

Generalists at the interface: Nematode transmission between wild and domestic ungulates.  

PubMed

Many parasitic nematode species are generalists capable of infecting multiple host species. The complex life cycle of nematodes, involving partial development outside of the host, facilitates transmission of these parasites between host species even when there is no direct contact between hosts. Infective nematode larvae persist in the environment, and where grazing or water sources are shared ingestion of parasite larvae deposited by different host species is likely. In this paper we examine the extent to which nematode parasite species have been observed in sympatric wild and domestic ungulates. First, using existing host-parasite databases, we describe expected overlap of 412 nematode species between 76 wild and 8 domestic ungulate host species. Our results indicate that host-specific parasites make up less than half of the nematode parasites infecting any particular ungulate host species. For wild host species, between 14% (for common warthog) and 76% (for mouflon) of parasitic nematode species are shared with domestic species. For domestic host species, between 42% (for horse) and 77% (for llamas/alpacas) of parasitic nematode species are shared with wild species. We also present an index of liability to describe the risk of cross-boundary parasites to each host species. We then examine specific examples from the literature in which transmission of nematode parasites between domestic and wild ungulates is described. However, there are many limitations in the existing data due to geographical bias and certain host species being studied more frequently than others. Although we demonstrate that many species of parasitic nematode are found in both wild and domestic hosts, little work has been done to demonstrate whether transmission is occurring between species or whether similar strains circulate separately. Additional research on cross-species transmission, including the use of models and of genetic methods to define strains, will provide evidence to answer this question. PMID:25426420

Walker, Josephine G; Morgan, Eric R

2014-12-01

426

Identification and characterization of alternative splicing in parasitic nematode transcriptomes  

PubMed Central

Background Alternative splicing (AS) of mRNA is a vital mechanism for enhancing genomic complexity in eukaryotes. Spliced isoforms of the same gene can have diverse molecular and biological functions and are often differentially expressed across various tissues, times, and conditions. Thus, AS has important implications in the study of parasitic nematodes with complex life cycles. Transcriptomic datasets are available from many species, but data must be revisited with splice-aware assembly protocols to facilitate the study of AS in helminthes. Methods We sequenced cDNA from the model worm Caenorhabditis elegans using 454/Roche technology for use as an experimental dataset. Reads were assembled with Newbler software, invoking the cDNA option. Several combinations of parameters were tested and assembled transcripts were verified by comparison with previously reported C. elegans genes and transcript isoforms and with Illumina RNAseq data. Results Thoughtful adjustment of program parameters increased the percentage of assembled transcripts that matched known C. elegans sequences, decreased mis-assembly rates (i.e., cis- and trans-chimeras), and improved the coverage of the geneset. The optimized protocol was used to update de novo transcriptome assemblies from nine parasitic nematode species, including important pathogens of humans and domestic animals. Our assemblies indicated AS rates in the range of 20-30%, typically with 2-3 transcripts per AS locus, depending on the species. Transcript isoforms from the nine species were translated and searched for similarity to known proteins and functional domains. Some 21 InterPro domains, including several involved in nucleotide and chromatin binding, were statistically correlated with AS genetic loci. In most cases, the Roche/454 data explored in this study are the only sequences available from the species in question; however, the recently published genome of the human hookworm Necator americanus provided an additional opportunity to validate our results. Conclusions Our optimized assembly parameters facilitated the first survey of AS among parasitic nematodes. The nine transcriptome assemblies, their protein translations, and basic annotations are available from Nematode.net as a resource for the research community. These should be useful for studies of specific genes and gene families of interest as well as for curating draft genome assemblies as they become available. PMID:24690220

2014-01-01

427

Tangling of Tethered Swimmers: Interactions between Two Nematodes  

NASA Astrophysics Data System (ADS)

The tangling of two tethered microswimming worms serving as the ends of "active strings" is investigated experimentally and modeled analytically. C. elegans nematodes of similar size are caught by their tails using micropipettes and left to swim and interact at different separations over long times. The worms are found to tangle in a reproducible and statistically predictable manner, which is modeled based on the relative motion of the worm heads. Our results provide insight into the intricate tangling interactions present in active biological systems.

Backholm, Matilda; Schulman, Rafael D.; Ryu, William S.; Dalnoki-Veress, Kari

2014-09-01

428

Molecular analysis of HSP90, a multi-faceted gene involved in the growth and development of free-living and plant parasitic nematodes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plant parasitic nematodes cause in excess of $100 billion of global crop losses each year. Cyst nematodes (Heterodera spp.) are endoparasitic root-feeding nematodes, and the soybean cyst nematode (SCN), Heterodera glycines, causes substantial losses in soybean yield in the U.S.A. as well as through...

429

Lethal Fighting in Nematodes Is Dependent on Developmental Pathway: Male-Male Fighting in the Entomopathogenic Nematode Steinernema longicaudum  

PubMed Central

Aggressive encounters occur between competitors (particularly males) throughout the animal kingdom, and in some species can result in severe injury and death. Here we describe for the first time lethal interactions between male nematodes and provide evidence that the expression of this behaviour is developmentally controlled. Males of the entomopathogenic nematode Steinernema longicaudum coil around each other, resulting in injuries, paralysis and frequently death. The probability of death occurring between pairs of males was affected by the developmental pathway followed, being much greater among males that had passed through the infective juvenile (IJ, or dauer) stage than among males that had not. Post-IJ males are found only in newly colonised hosts, typically with few competing males present. Killing those few competitors may secure valuable resources (both females and a host cadaver for nourishment of offspring). Non-IJ males develop in subsequent generations within a host cadaver, where the presence of many closely related male competitors increases the risk:benefit ratio of fighting. Thus, passage through the IJ stage primes males for enhanced aggression in circumstances where this is more likely to result in increased reproductive success. Fighting occurred between males developing in mixed-sex social groups, indicating that it is an evolved trait and not an abnormal response to absence of females. This is supported by finding high mortality of males, but not of females, across a range of population densities in insect cadavers. We propose that these nematodes, with their relatively simple organization, may be a useful model for studies of aggression. PMID:24586738

Zenner, Annemie N. R. L.; O'Callaghan, Kathryn M.; Griffin, Christine T.

2014-01-01

430

Postplant Fumigation with DBCP for Citrus Nematode Control in Florida.  

PubMed

Eleven citrus groves of diverse varieties and ages infected with Tylenchulus semipenetrans growing in differing soils in Florida were treated with three rates of 1,2-dibromo-3-chloropropane (DBCP) applied by various means. Yield, fruit size, and T. semipenetrans populations in the roots were compared between DBCP-treated and untreated trees over a period of I-3 yr. Maximum fruit size and yield were obtained by applying DBCP at 38-58 kg/hectare (ha) (34-52 lb/acre); whereas best nematode control was with a rate of 77 kg/ha (69 lb/acre). Application of chemical emulsion with a special, drilled, low-profile sprinkler irrigation ground pipe was the most suitable method. Effect of DBCP treatment generally lasted for 3 yr. A mean annual I. 1% increase in fruit diameter, 15.2% increase in fruit yield and a 55.7% decrease incitrus nematode populations was found for D BC P-treated trees in contrast to untreated trees. PMID:19319363

Tarjan, A C; O'Bannon, J H

1974-01-01

431

Effects of Rhizobacteria on Soybean Cyst Nematode, Heterodera glycines  

PubMed Central

Rhizobacteria were isolated from the rhizoplane and rhizosphere of soybean plants from fields in Arkansas and tested for their effect on numbers of soybean cyst nematode (Heterodera glycines). In initial greenhouse tests in heat-treated silt loam soil, 138 of the 201 bacterial isolates tested had no influence on numbers of cysts and eggs + second-stage juveniles (J2) of H. glycines, 36 reduced (suppressive isolates) and 27 increased (enhancing isolates) numbers of cysts and (or) eggs + J2 when compared to the controls (P ? 0.05). When 20 suppressive and five enhancing isolates were retested in the same soil, the results were highly variable and inconclusive. The 25 isolates were then evaluated in vitro for their effects on eggs and J2 of H. glycines. No clear relationship was detected between the inhibition of egg hatch or immobilization of J2 in vitro and antagonistic activity toward nematodes in vivo. Amendment of the soil with 0.1% (w/w) peptone or casein hydrolysate did not improve the effects of suppressive isolates on numbers of H. glycines. Nineteen of the 25 isolates were identified based on analysis of fatty acid methyl esters, and they are in 11 different genera. PMID:19270992

Tian, Honglin; Riggs, Robert D.

2000-01-01

432

Plant-parasitic Nematodes Associated with Cherry Rootstocks in Michigan  

PubMed Central

In two field trials, 10-year-old sweet and tart cherry rooted on 'Mazzard', 'Mahaleb', 'MXM 2', 'MXM 14', 'MXM 39', 'MXM 60', 'MXM 97', and 'Colt' showed 10-203 Pratylenchus penetrans per g fresh root from all tart rootstocks, and up to 46 Pratylenchus, Criconemella, and Xiphinema spp. per 100 cm³ soil. Infestation of soil containing 1-year-old Mazzard, Mahaleb, MXM 60, 'GI148-1', and 'G1148-8' with 625/100 cm³ soil of either P. penetrans or C. xenoplax resulting in final nematode population densities of 123-486 and 451-2,496/g fresh root plus 100 cm³ soil, respectively, and had little effect on plant height or dry weight after 157 days in a greenhouse. Population densities of neither nematode differed among the five rootstocks. In a second greenhouse experiment, soil containing the same rootstocks was infested with P. penetrans (1,250/100 cm³ soil), maintained for 8 months in a greenhouse, 4 months in a cold room (2-4 C), and 3 additional months in a greenhouse. The number of P. penetrans recovered at the end of 475 days was approximately 10% of those recovered in the first experiment, probably due to the cold treatment. The ability of P. penetrans and C. xenoplax to infect the cherry rootstocks may be of concern in cherry management programs. PMID:19279962

Melakeberhan, H.; Bird, G. W.; Perry, R.

1994-01-01

433

Plant-parasitic Nematodes Associated with Cherry Rootstocks in Michigan.  

PubMed

In two field trials, 10-year-old sweet and tart cherry rooted on 'Mazzard', 'Mahaleb', 'MXM 2', 'MXM 14', 'MXM 39', 'MXM 60', 'MXM 97', and 'Colt' showed 10-203 Pratylenchus penetrans per g fresh root from all tart rootstocks, and up to 46 Pratylenchus, Criconemella, and Xiphinema spp. per 100 cm(3) soil. Infestation of soil containing 1-year-old Mazzard, Mahaleb, MXM 60, 'GI148-1', and 'G1148-8' with 625/100 cm(3) soil of either P. penetrans or C. xenoplax resulting in final nematode population densities of 123-486 and 451-2,496/g fresh root plus 100 cm(3) soil, respectively, and had little effect on plant height or dry weight after 157 days in a greenhouse. Population densities of neither nematode differed among the five rootstocks. In a second greenhouse experiment, soil containing the same rootstocks was infested with P. penetrans (1,250/100 cm(3) soil), maintained for 8 months in a greenhouse, 4 months in a cold room (2-4 C), and 3 additional months in a greenhouse. The number of P. penetrans recovered at the end of 475 days was approximately 10% of those recovered in the first experiment, probably due to the cold treatment. The ability of P. penetrans and C. xenoplax to infect the cherry rootstocks may be of concern in cherry management programs. PMID:19279962

Melakeberhan, H; Bird, G W; Perry, R

1994-12-01

434

The mitochondrial genome of the soybean cyst nematode, Heterodera glycines.  

PubMed

We sequenced the entire coding region of the mitochondrial genome of Heterodera glycines. The sequence obtained comprised 14.9 kb, with PCR evidence indicating that the entire genome comprised a single, circular molecule of approximately 21-22 kb. The genome is the most T-rich nematode mitochondrial genome reported to date, with T representing over half of all nucleotides on the coding strand. The genome also contains the highest number of poly(T) tracts so far reported (to our knowledge), with 60 poly(T) tracts ? 12 Ts. All genes are transcribed from the same mitochondrial strand. The organization of the mitochondrial genome of H. glycines shows a number of similarities compared with Radopholus similis, but fewer similarities when compared with Meloidogyne javanica. Very few gene boundaries are shared with Globodera pallida or Globodera rostochiensis. Partial mitochondrial genome sequences were also obtained for Heterodera cardiolata (5.3 kb) and Punctodera chalcoensis (6.8 kb), and these had identical organizations compared with H. glycines. We found PCR evidence of a minicircular mitochondrial genome in P. chalcoensis, but at low levels and lacking a noncoding region. Such circularised genome fragments may be present at low levels in a range of nematodes, with multipartite mitochondrial genomes representing a shift to a condition in which these subgenomic circles predominate. PMID:21745140

Gibson, Tracey; Farrugia, Daniel; Barrett, Jeff; Chitwood, David J; Rowe, Janet; Subbotin, Sergei; Dowton, Mark

2011-07-01

435

Tropical rotation crops influence nematode densities and vegetable yields.  

PubMed

The effects of eight summer rotation crops on nematode densities and yields of subsequent spring vegetable crops were determined in field studies conducted in north Florida from 1991 to 1993. The crop sequence was as follows: (i) rotation crops during summer 1991; (ii) cover crop of rye (Secale cereale) during winter 1991-92; (iii) 'Lemondrop L' squash (Cucurbita pepo) during spring 1992; (iv) rotation crops during summer 1992; (v) rye during winter 1992-93; (vi) 'Classic' eggplant (Solanum melongena) during spring 1993. The eight summer crop rotation treatments were as follows: 'Hale' castor (Ricinus communis), velvetbean (Mucuna deeringiana), sesame (Sesamum indicum), American jointvetch (Aeschynomene americana), weed fallow, 'SX- 17' sorghum-sudangrass (Sorghum bicolor x S. sudanense), 'Kirby' soybean (Glycine max), and 'Clemson Spineless' okra (Hibiscus esculentus) as a control. Rotations with castor, velvetbean, American jointvetch, and sorghum-sudangrass were most effective in maintaining the lowest population densities of Meloidogyne spp. (a mixture of M. incognita race 1 and M. arenaria race 1), but Paratrichodorus minor built up in the sorghum-sudangrass rotation. Yield of squash was lower (P nematodes in the field and for improving yields of subsequent vegetable crops. PMID:19279897

McSorley, R; Dickson, D W; de Brito, J A; Hochmuth, R C

1994-09-01

436

Plant-Parasitic Nematodes of South Viet Nam  

PubMed Central

Between 1974 and 1978, 2,842 identifications of plant-parasitic nematodes were made from more than 1,700 soil and plant samples collected in eight provinces of South Viet Nam. Species in nine genera—Helicotylenchus, Criconemoides, Meloidogyne, Pratylenchus, Tylenchorhynchus, Hoplolaimus, Hirschmanniella, Xiphinema, and Rotylenchulus—comprised 96.1% of the identifications; the remaining 3.9% were species of 11 genera. Fourteen genera were associated with rice which was grown on about 2,500,000 ha in 1970. Of these, Ditylenchus, Hirschmanniella, and Meloidogyne were most important. Ditylenchus angustus caused severe damage to about 50,000 ha of flooded rice in the Mekong Delta in 1976. Hirschmanniella spp. were found in all samples examined from flooded rice fields. Meloidogyne spp. were common in rice seedbeds, upland rice, and rice not kept flooded continuously. Meloidogyne and Pratylenchus spp. were found in roots of 22 of the 32 crop plants sampled. Little or no attempt was made in South Viet Nam to control nematodes. PMID:19295809

Khuong, Gguyen B.

1983-01-01

437

Family of FLP Peptides in Caenorhabditis elegans and Related Nematodes.  

PubMed

Neuropeptides regulate all aspects of behavior in multicellular organisms. Because of their ability to act at long distances, neuropeptides can exert their effects beyond the conventional synaptic connections, thereby adding an intricate layer of complexity to the activity of neural networks. In the nematode Caenorhabditis elegans, a large number of neuropeptide genes that are expressed throughout the nervous system have been identified. The actions of these peptides supplement the synaptic connections of the 302 neurons, allowing for fine tuning of neural networks and increasing the ways in which behaviors can be regulated. In this review, we focus on a large family of genes encoding FMRFamide-related peptides (FaRPs). These genes, the flp genes, have been used as a starting point to identifying flp genes throughout Nematoda. Nematodes have the largest family of FaRPs described thus far. The challenges in the future are the elucidation of their functions and the identification of the receptors and signaling pathways through which they function. PMID:25352828

Li, Chris; Kim, Kyuhyung

2014-01-01

438

Active uptake of artificial particles in the nematode Caenorhabditis elegans.  

PubMed

Feeding and food choice are crucial to the survival of an animal. The nematode Caenorhabditis elegans feeds on various microorganisms in nature, and is usually fed Escherichia coli in the laboratory. To elucidate the mechanisms of food/non-food discrimination in C. elegans, we examined the accumulation of various fluorescent polystyrene microspheres in the absence and presence of bacterial food. In the absence of food and on agar plates, C. elegans worms actively accumulated 0.5 and 1 ?m diameter microspheres, whereas those microspheres <0.5 ?m or >3 ?m were rarely accumulated. Carboxylate microspheres were accumulated more than sulfate or amine microspheres. These results of accumulation in the absence of food probably well simulate uptake of or feeding on the microspheres. Presence of food bacteria even at bacteria:nematode ratios of 1:100 or 1:10 significantly reduced accumulation of 0.5 ?m microspheres, and accumulation was reduced to approximately one-fourth of that observed in the absence of bacteria at a ratio of 1:1. When accumulation of microspheres was examined with the chemical sense mutants che-2, tax-2, odr-1 and odr-2, or the feeding mutant eat-1, all the mutants showed less accumulation than the wild type in the absence of food. In the presence of food, the che-2 mutant showed more accumulation than the wild type. It is possible that C. elegans discriminates food both physically, based on size, and chemically, based on taste and olfaction. PMID:22399663

Kiyama, Yuya; Miyahara, Kohji; Ohshima, Yasumi

2012-04-01

439

Caenorhabditis elegans: A Simple Nematode Infection Model for Penicillium marneffei  

PubMed Central

Penicillium marneffei, one of the most important thermal dimorphic fungi, is a severe threat to the life of immunocompromised patients. However, the pathogenic mechanisms of P. marneffei remain largely unknown. In this work, we developed a model host by using nematode Caenorhabditis elegans to investigate the virulence of P. marneffei. Using two P. marneffei clinical isolate strains 570 and 486, we revealed that in both liquid and solid media, the ingestion of live P. marneffei was lethal to C. elegans (P<0.001). Meanwhile, our results showed that the strain 570, which can produce red pigment, had stronger pathogenicity in C. elegans than the strain 486, which can’t produce red pigment (P<0.001). Microscopy showed the formation of red pigment and hyphae within C. elegans after incubation with P. marneffei for 4 h, which are supposed to be two contributors in nematodes killing. In addition, we used C. elegans as an in vivo model to evaluate different antifungal agents against P. marneffei, and found that antifungal agents including amphotericin B, terbinafine, fluconazole, itraconazole and voriconazole successfully prolonged the survival of nematodesinfected by P. marneffei. Overall, this alternative model host can provide us an easy tool to study the virulence of P. marneffei and screen antifungal agents. PMID:25268236

Huang, Xiaowen; Li, Dedong; Xi, Liyan; Mylonakis, Eleftherios

2014-01-01

440

Nematodes in Dryland Field Crops in the Semiarid Pacific Northwest United States  

PubMed Central

Soils and roots of field crops in low-rainfall regions of the Pacific Northwest were surveyed for populations of plantparasitic and non-plant-parasitic nematodes. Lesion nematodes (Pratylenchus species) were recovered from 123 of 130 non-irrigated and 18 of 18 irrigated fields. Pratylenchus neglectus was more prevalent than P. thornei, but mixed populations were common. Population densities in soil were affected by crop frequency and rotation but not by tillage or soil type (P < 0.05). Many fields (25%) cropped more frequently than 2 of 4 years had potentially damaging populations of lesion nematodes. Pratylenchus neglectus density in winter wheat roots was inversely correlated with grain yield (r2 = 0.64, P = 0.002), providing the first field-derived evidence that Pratylenchus is economically important in Pacific Northwest dryland field crops. Stunt nematodes (Tylenchorhynchus clarus and Geocenamus brevidens) were detected in 35% of fields and were occasionally present in high numbers. Few fields were infested with pin (Paratylenchus species) and root-knot (Meloidogyne naasi and M. chitwoodi) nematodes. Nematodes detected previously but not during this survey included cereal cyst (Heterodera avenae), dagger (Xiphinema species), and root-gall (Subanguina radicicola) nematodes. PMID:19262788

Smiley, Richard W.; Merrifield, Kathy; Patterson, Lisa-Marie; Whittaker, Ruth G.; Gourlie, Jennifer A.; Easley, Sandra A.

2004-01-01

441

Response of Plant Parasitic and Free Living Soil Nematodes to Composted Animal Manure Soil Amendments  

PubMed Central

In an outside pot experiment, dry pig manure processed on pine sawdust litter and fermented for seven days by house fly larvae (fermented manure), and pine sawdust applied alone, and in combination with a spring application of inorganic nitrogen fertilizer were used to determine their effects on plant parasitic and free-living soil nematodes on sugar beets (cv. Antek). Non amended soil was used as a control. All treatments with fermented pig manure and sawdust with nitrogen fertilizer decreased number of plant parasitic nematodes and also root-fungal feeding nematodes compared to the untreated control. Sawdust applied alone had no effect on plant parasitic and root-fungal feeding nematode suppression. Free-living nematodes which were mainly bacteriovores and fungivores were significantly more abundant in soil amended with fermented pig manure, while the sawdust had no effect on these nematodes. The effect of all tested treatments on omnivores-predators was rather random, and in general, the number of these nematodes decreased after soil amendment applications compared to the untreated control. PMID:23482503

Ren?o, M.; Ková?ik, P.

2012-01-01

442

Nematode assemblages from the Kandalaksha Depression (White Sea, 251-288 m water depth)  

NASA Astrophysics Data System (ADS)

The shallow-water nematodes of the White Sea are relatively well studied; however, information on the nematode fauna inhabiting the deepest part of this sea is very scarce. The composition of the nematode assemblages (at species and genus level) was studied in samples collected during four sampling occasions in the deepest part of the Kandalaksha Depression (the White Sea) in July 1998, October 1998, May 1999, and November 1999. Samples were collected from a depth of 251-288 m with the aid of a multicorer. In total, 59 nematode morphotypes belonging to 37 genera and 18 families were distinguished. The genera Sabatieria and Filipjeva dominated at all stations, followed by Aponema, Desmoscolex, and Quadricoma. The composition of the dominant genera can be considered typical for this depth range in temperate and Arctic waters, although Filipjeva and Aponema were among the dominant genera for the first time. The most abundant species were Sabatieria ornata, Aponema bathyalis, and Filipjeva filipjevi. In general, diversity of the nematode assemblages was lower than in the temperate and Arctic continental shelf and slope with reduced evenness and species richness. The evenness of nematode assemblages and other diversity indices decreased with increasing sediment depth. Based on the valid species and genera recorded, the nematode fauna of the Kandalaksha Depression showed a higher resemblance to that found in the shallow waters of Kandalaksha Bay.

Miljutin, Dmitry M.; Miljutina, Maria A.; Tchesunov, Alexei V.; Mokievsky, Vadim O.

2014-03-01

443

Nematode community structure in dogwood, maple, and peach nurseries in tennessee.  

PubMed

Nursery blocks (48 dogwood, 27 maple, 17 peach) in 20 middle Tennessee nurseries were sampled for nematodes in March,July, and October 1981. Dogwoods and maples were grouped in three age classes: 1-2, 3-5, and 10+ years. Nematodes were extracted from soil samples, counted, and assigned to trophic groups as follows: plant parasites, microbivores, fungivores, predators, and omnivores (= Dorylaimida). Total nematode numbers per 200 cm s soil ranged from 52 to 9,166 (mean = 1,785 +/- 1,420). Nematodes were more abundant in dogwood and maple than in peach blocks, and their numbers were significantly correlated with percentage of weed ground cover and number of weed species. Nematode numbers in dogwood sites were also correlated with dogwood age. Microbivores were the most abundant trophic group in all sites, followed by plant parasites, fungivores, omnivores, and predators. Nematode communities in nursery sites shared characteristics of both undisturbed and agricultural habitats. Degree and diversity of plant ground cover appeared to be the most important factors determining nematode community structure. PMID:19294070

Niblack, T L; Bernard, E C

1985-04-01

444

Host Suitability of the Olive Cultivars Arbequina and Picual for Plant-Parasitic Nematodes  

PubMed Central

Host suitability of olive cultivars Arbequina and Picual to several plant-parasitic nematodes was studied under controlled conditions. Arbequina and Picual were not suitable hosts for the root-lesion nematodes Pratylenchus fallax, P. thornei, and Zygotylenchus guevarai. However, the ring nematode Mesocriconema xenoplax and the spiral nematodes Helicotylenchus digonicus and H. pseudorobustus reproduced on both olive cultivars. The potential of Meloidogyne arenaria race 2, M. incognita race 1, and M. javanica, as well as P. vulnus and P. penetrans to damage olive cultivars, was also assessed. Picual planting stocks infected by root-knot nematodes showed a distinct yellowing affecting the uppermost leaves, followed by a partial defoliation. Symptoms were more severe on M. arenaria and M. javanica-infected plants than on M. incognita-infected plants. Inoculation of plants with 15,000 eggs + second-stage juveniles/pot of these Meloidogyne spp. suppressed the main height of shoot and number of nodes of Arbequina, but not Picual. Infection by each of the two lesion nematodes (5,000 nematodes/pot) or by each of the three Meloidogyne spp. suppressed (P < 0.05) the main stem diameter of both cultivars. On Arbequina, the reproduction rate of Meloidogyne spp. was higher (P < 0.05) than that of Pratylenchus spp.; on Picual, Pratylenchus spp. reproduction was higher (P < 0.05) than that of Meloidogyne spp. PMID:19265971

Nico, A. I.; Jiménez-Díaz, R. M.; Castillo, P.

2003-01-01