Developmental Studies on Haemonchus contortus Rudolphi (1803)

Berberian, Joseph F.; Mizelle, John D.

doi:10.2307/2422408

Cited by 29 publications

(11 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The amount of DNA found within an individual egg will depend on several factors including the nematode species, the developmental stage that is excreted with the feces, the storage time and conditions (in particular temperature, humidity and availability of oxygen) [8], [9]. Therefore, nematode DNA content in a sample will always vary with several factors that are difficult or impossible to control – at least for routine diagnostics with veterinarians sending in samples to central laboratories.…”

Section: Introductionmentioning

confidence: 99%

Discrimination of Gastrointestinal Nematode Eggs from Crude Fecal Egg Preparations by Inhibitor-Resistant Conventional and Real-Time PCR

et al. 2013

View full text Add to dashboard Cite

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

show abstract

Section: Introductionmentioning

confidence: 99%

Discrimination of Gastrointestinal Nematode Eggs from Crude Fecal Egg Preparations by Inhibitor-Resistant Conventional and Real-Time PCR

et al. 2013

View full text Add to dashboard Cite

show abstract

“…The data used to derive these relationships were taken from a collection of studies using different nematode isolates and in many cases quite different methodologies. For example, while some studies measured the development of eggs to L3 within faecal pellets (Pandey et al 1989;Coyne and Smith 1992) others extracted the eggs and grew the larvae on various forms of nutrient medium (Berberian and Mizelle 1957;Salih and Grainger 1982). These differences undoubtedly influenced the development and survival of the different stages (Wang 1967;Pandey et al 1989).…”

Section: Resultsmentioning

confidence: 99%

“…Similarly, only 1% of unembryonated eggs and 7% of L2 survived for 1 hour at 458C (Todd et al 1976). No H. contortus L3 were recovered at 37.88C and all eggs were dead within 5 days (Berberian and Mizelle 1957). When T. circumcincta eggs were incubated at 408C or 458C, none or very few survived to L3 (Salih and Grainger 1982;Pandey et al 1989).…”

Section: Leathwickmentioning

confidence: 96%

“…Short-term oscillations in temperature from 158C to À18C significantly decreased survival of H. contortus compared with a constant 158C (Troell et al 2005). At just above freezing, 67-83% of H. contortus eggs died within 1 day (Shorb 1944) and at 5.68C all were dead within 5 days (Berberian and Mizelle 1957). However, a proportion of embryonated eggs may survive longer than 30 days at 48C (Todd et al 1976).…”

Section: Leathwickmentioning

confidence: 99%

See 1 more Smart Citation

The influence of temperature on the development and survival of the pre-infective free-living stages of nematode parasites of sheep

Leathwick

2013

New Zealand Veterinary Journal

View full text Add to dashboard Cite

Consistent accurate estimation of the proportion of eggs developing to L3 in the field will require the integration of temperatures at relatively short time intervals. This will be necessary to capture the effect of temperatures fluctuating, even for short periods, to temperature values which are less than optimal for development. The use of daily mean temperatures, or means taken over longer periods, is likely to yield inaccurate estimates of development at least some of the time.

show abstract

“…This is because refrigerated storage will reduce the number of larvae recovered and distort the species fractions as different species are susceptible to varying degrees to disruption by refrigeration (McKenna 1998, van Wyk and van Wyk 2002, Troell and others 2005). Indeed, some authors report disintegration of H contortus eggs after only 120 hours at 5.5 o C (Berberian and Mizelle 1957). The authors have successfully recovered Teladorsagia L3 larvae from faeces refrigerated up to four days.…”

Section: Nematode Parasitesmentioning

confidence: 99%

Ruminant coprological examination: beyond the McMaster slide

Crilly

Sargison

2015

In Practice

View full text Add to dashboard Cite

Sustainable and effective control of nematode and trematode infections of ruminants requires an understanding of the farm-specific epidemiology of the parasites. To this end, a variety of diagnostic and monitoring techniques can be employed by the veterinary practitioner, of which the most commonly used is the faecal worm egg count (FWEC). This article discusses other techniques which can add detail to the information gained from FWECs and detect parasites not amenable to egg flotation techniques.

show abstract

Developmental Studies on Haemonchus contortus Rudolphi (1803)

Cited by 29 publications

References 2 publications

Discrimination of Gastrointestinal Nematode Eggs from Crude Fecal Egg Preparations by Inhibitor-Resistant Conventional and Real-Time PCR

Discrimination of Gastrointestinal Nematode Eggs from Crude Fecal Egg Preparations by Inhibitor-Resistant Conventional and Real-Time PCR

The influence of temperature on the development and survival of the pre-infective free-living stages of nematode parasites of sheep

Ruminant coprological examination: beyond the McMaster slide

Contact Info

Product

Resources

About