Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-1955
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  This experiment was designed to examine the growth, proportion of stages, and fecundity of an Oesophagostomum dentatum population by transplantation of a known small number of worms from a high-density population into helminth-naive recipient pigs. Approximately 1,500 4-week-old worms [69% fourth-stage larvae (L4), 31% adult worms] were transplanted into each of 5 recipient pigs (group B), and these pigs, along with a group of 5 high-level-infection control pigs (group C), were killed at 4 weeks after transplantation to determine and compare the worm burdens. By 2 weeks after transplantation and throughout the experiment, fecal egg counts of group B exceeded those of group C and the fecundity of the worms was higher, though not statistically significantly so, in the transplanted worms. In the recipient pigs, all worms (approx. 70% establishment) had developed to the adult stage and were significantly longer than worms recovered from the group C pigs.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-1955
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The agar-gel migration technique has previously been described, however, aspects regarding the effect of timing on worm migration needed further scrutiny. In the first experiment, pigs inoculated with Oesophagostomum dentatum were slaughtered simultaneously and their intestines stored at 21–23 °C until processed pairwise 2, 4, 6, 8, 12 and 18 h after slaughter. More than 95% of the worms migrated out of the agar if processed within 6 h. In the second experiment, intestines were treated immediately after slaughter and the migratory speed of adult worms or 4th-stage larvae of O. dentatum or O. quadrispinulatum, or adult Hyostrongylus rubidus were studied. For both Oesophagostomum species, more than 90% of the worms were recovered within 1 h. H. rubidus was significantly slower; however, approximately 98% of the worms had migrated out of the agar-gel by 20 h. This information is essential in planning experiments where recovery of live worms is of value.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-1955
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Nodular worms are common parasites of pigs, and research has recently started to focus on the biology of these nematodes. However, the methods for delineation of species at immature developmental stages and␣for␣differentiation of various lines of the same species␣remain limited. For differentiation of porcine Oesophagostomum species and strains by genomic fingerprinting, random amplified polymorphic DNA-polymerase chain reaction was performed on DNA derived from 20 larval batches of anthelmintic-susceptible and resistant strains and isolates of these nematodes and 2 ruminant Oesophagostomum spp. Polymorphic DNA markers could be amplified with 9 of the 33 primers tested. In all, 13 markers were species-specific and 6 markers could differentiate between strains or groups of strains. With a combination of the latter, artificially selected anthelmintic-resistant strains and the susceptible mother strain of O. dentatum could be delineated. When single adult worms were compared, considerable variations between strains of the same species and between individuals from the same strain could be detected. The differentiation of Oesophagostomum strains and species at all parasitic stages on the basis of genetic markers could greatly facilitate studies on the biology of these parasites.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Parasitology research 84 (1998), S. 783-786 
    ISSN: 1432-1955
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract For a study on the occurrence of resistance to reinfection with porcine nodular worm species, pigs were infected twice weekly with 1,000 infective larvae (L3) of Oesophagostomumquadrispinulatum for 8 weeks. All pigs, including noninfected controls, were then treated with fenbendazole. At 10 days after treatment, all pigs received a single challenge inoculation of 5,000 L3 of either O. dentatum or O. quadrispinulatum, respectively. Pigs were slaughtered at 6 weeks after the challenge infection for determination of their worm burdens. The pigs trickle- and challenge-infected with O. quadrispinulatum had significantly lower egg excretion levels (P 〈 0.01) and worm burdens (P 〈 0.05) than challenge control pigs, thus indicating some degree of host immunity against the homologous challenge infection. No resistance to reinfection was evident for the heterologous challenge infection. This study elucidates further aspects of the interaction between nodular worm species in the pig.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-1955
    Keywords: Abbreviations L3 Third-stage larvae L4 Fourth-stage larvae ; SDS Sodium dodecyl sulfate ; PAGE polyacrylamide gel electrophoresis ; IEP Isoelectric point ; IEF Isoelectric focusing ; FPLC Fast protein liquid chromatography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract In the search for a serology tool for the diagnosis of nonpatent as well as patent infections with Oesophagostomum dentatum in pigs a water-soluble, unglycosilated antigen of about 30 kDa specific for the third-stage larvae of the parasite was purified by ion-exchange chromatography. In Western blots, the antigen was first detected by antibodies at day 7 postinfection. Cross-reactivity with O. quadrispinulatum, Ascaris suum, or Trichuris suis was not detected. It is suggested that this protein is a suitable tool for the species-specific serodiagnosis of O. dentatum infection in pigs.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1573-0832
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract In sorghum seed stored at 22–25° C for 535 days, invasion by storage fungi and loss of germinability increased greatly with small increases in moisture content between 13.5 and 15.5 %. Seeds dried for 18 hours at 70° C, then exposed to a relative humidity of 75 %, had a lower equilibrium moisture content, but were more heavily invaded by storage fungi and lost germinability fsater, than those that had been conditioned to 20 % moisture before storage at 75 % relative humidity. The 10 samples of Grade No. 2 sorghum examined averaged about 13.0 % moisture, germinated an average of 59 %, yieldedAlternaria from 75 % of the surface-disinfected kernels andAspergillus glaucus from 4 %; judged by these criteria, the lots from which the samples came were in good condition for continued storage.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1432-1955
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The genetic diversity in eight strains of Oesophagostomum dentatum and O. quadrispinulatum was investigated by the electrophoresis study of ten enzyme systems. The loci Idh-2, Fbp, Sdh, and Pgm were found to be diagnostic between the species examined. Both the proportion of fixed allelic differences (26.3%) and the genetic distance coefficient (D=0.54) are well above the range for differentiation of valid species. Isoenzyme patterns of susceptible and resistant lines of O. dentatum showed at polymorphic loci a reduced genetic heterogeneity in the latter group. No qualitative difference in terms of the presence/absence of alleles was observed among susceptible and resistant isolates with the enzymes studied. The detection of one possible hybrid indicates that introgression in O. dentatum and O. quadrispinuatum may occur.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1432-1955
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract To define prepatent periods of different Oesophagostomum spp. isolates we carried out two separate experiments, one using two monospecific laboratory isolates and another using laboratory isolates as well as isolates obtained from pig herds having different management systems and with different anthelmintic treatment histories. Pigs were inoculated with 1,000–2,000 infective larvae. Fecal samples were collected daily beginning on days 15 and 16 postinoculation (p.i.). Fecal cultures were set up at different times to yield larvae that could be identified by DNA analyses. All pigs started to excrete eggs on days 18–24 p.i. The mean prepatent period was 20.2 ± 1.4 days, with no significant difference being observed between species and isolates. Prepatent periods of 17–19 days were found for the monospecific laboratory isolates of O. dentatum and O. quadrispinulatum. These findings conflict with parasitology textbooks; therefore, suggestions as to the possible reasons for the observed short prepatent periods are given.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-1955
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We examined the impact of different Oesophagostomum dentatum dose levels and durations of infection on the development and infectivity of the following generation. Pigs were trickle-infected with 200, 2,000 or 20,000 L3/week over 20 weeks. Egg hatch assays were performed at monthly intervals; however, no consistent differences were found between any of the dose groups in the development of eggs into first-stage larvae. To compare larval infectivity, larvae were derived from faecal cultures set up from the low- and the high-dose groups in the early and the late part of the experiment, and were inoculated into helminth-free pigs (5,000 L3/pig). Worm establishments were significantly higher (P 〈 0.05) in the group of pigs receiving larvae derived early in the experiment from the low-dose group compared with the two groups receiving larvae from high-dose groups, thus indicating an adverse effect of high doses of trickle infection on the later infectivity of L3 larvae derived from excreted eggs.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...