Species-specific amplification by PCR of ribosomal DNA from some equine strongyles

Parasitology ◽  
1999 ◽  
Vol 119 (1) ◽  
pp. 69-80 ◽  
Author(s):  
G.-C. HUNG ◽  
R. B. GASSER ◽  
I. BEVERIDGE ◽  
N. B. CHILTON

The first and second internal transcribed spacer sequences of 28 morphologically-defined species of horse strongyle were characterized, and specific oligonucleotide primers were designed for some species based on the nucleotide differences. Utilizing these primers, a PCR approach was developed for the specific amplification of ribosomal DNA of Strongylus vulgaris, Cyathostomum catinatum, Cylicocyclus nassatus, Cylicostephanus longibursatus or Cylicostephanus goldi. The method allowed the species-specific amplification of parasite DNA derived from faecal samples and/or copro-cultures, demonstrating the potential of the approach for the diagnosis of equine strongyloidosis. The establishment of this PCR assay also has implications for studying the biology and epidemiology of equine strongyles and anthelmintic resistance using faecal egg count reduction tests.

2016 ◽  
Vol 53 (1) ◽  
pp. 24-30 ◽  
Author(s):  
T. Kupčinskas ◽  
I. Stadalienė ◽  
A. Šalomskas ◽  
P. Trusevičius ◽  
M. Varady ◽  
...  

SummaryThis study determined the prevalence of anthelmintic resistance (AR) in parasitic nematodes on smallholder sheep farms in Lithuania from April to November 2014. Faecal samples were collected from two groups of 10-15 sheep treated with fenbendazole (FBZ) or ivermectin (IVM) on 18 sheep farms. Two samples were collected from each group: on day zero (T1) and 10-14 days after treatment. Faecal egg counts (eggs per gramme, EPG) were determined using a modified McMaster technique. Animals with < 140 EPG on day zero were removed from the analysis. The prevalence of AR was estimated using the in vivo faecal egg count reduction test. AR to FBZ was detected on three of 15 farms where FBZ was used (20 %) and was suspected on one farm (6.7 %). AR to IVM was detected on two of 16 farms where IVM was used (12.5 %). The main species of resistant gastrointestinal nematodes (GINs) identified after treatment were Teladorsagia spp. and Trichostrongylus spp. A questionnaire surveying 71 sheep farmers estimated that 71.8 % of sheep farmers used anthelmintics against GINs. IVM was the most frequently (68.6 %) applied anthelmintic, and 62.7 % of the respondents reported treating their animals twice a year. This study confirmed the presence of AR to GIN infections on sheep farms in Lithuania. Future studies should assess the prevalence of AR to GIN infection using in vitro methods.


2014 ◽  
Vol 89 (6) ◽  
pp. 760-763 ◽  
Author(s):  
B. Lassen ◽  
S.-M. Peltola

AbstractThere is evidence of resistance in horses to anthelmintic treatment using ivermectin and pyrantel. However, little information is available about the parasites, treatment practices or anthelmintic resistance in the horse population in Estonia. In the present study, we examined 41 trotting and riding horses aged < 3 years from four stables in Estonia. Faecal samples were collected, and horses were selected for treatment if the nematode egg count per gram faeces exceeded 200. Horses (n= 32) that shed strongyle-type eggs were treated with pyrantel, whereas Parascaris equorum-positive animals received ivermectin. Up to 78% of horses required anthelmintic treatment and the efficiency of the anthelmintics was evaluated using a faecal egg count reduction test. Resistance of P. equorum was observed in 50% of horses treated with ivermectin and of strongyles in 27% of horses treated with pyrantel. Ivermectin treatment resulted in a mean reduction of 100% for strongyle eggs and an 89% reduction in P. equorum, and pyrantel-treated horses exhibited an 88% reduction in strongyle eggs. These results are considered to be the first indication of resistance to pyrantel, but further studies of ivermectin resistance are required. According to questionnaires completed by the owners of horses, resistance might be explained by a lack of evidence-based strategies, a strong preference for using ivermectin and possibly a subjective evaluation of the body weight of horses.


2008 ◽  
Vol 99 (1) ◽  
pp. 41-49 ◽  
Author(s):  
L.L. Koekemoer ◽  
E.A. Misiani ◽  
R.H. Hunt ◽  
R.J. Kent ◽  
D.E. Norris ◽  
...  

AbstractHouse-resting Anopheles mosquitoes are targeted for vector control interventions; however, without proper species identification, the importance of these Anopheles to malaria transmission is unknown. Anopheles longipalpis, a non-vector species, has been found in significant numbers resting indoors in houses in southern Zambia, potentially impacting on the utilization of scarce resources for vector control. The identification of An. longipalpis is currently based on classical morphology using minor characteristics in the adult stage and major ones in the larval stage. The close similarity to the major malaria vector An. funestus led to investigations into the development of a molecular assay for identification of An. longipalpis. Molecular analysis of An. longipalpis from South Africa and Zambia revealed marked differences in size and nucleotide sequence in the second internal transcribed spacer (ITS2) region of ribosomal DNA between these two populations, leading to the conclusion that more than one species was being analysed. Phylogenetic analysis showed the Zambian samples aligned with An. funestus, An. vaneedeni and An. parensis, whereas the South African sample aligned with An. leesoni, a species that is considered to be more closely related to the Asian An. minimus subgroup than to the African An. funestus subgroup. Species-specific primers were designed to be used in a multiplex PCR assay to distinguish between these two cryptic species and members of the An. funestus subgroup for which there is already a multiplex PCR assay.


2020 ◽  
Vol 57 (2) ◽  
pp. 163-170
Author(s):  
R. A. Papini ◽  
C. Orsetti ◽  
M. Sgorbini

SummaryThe aim of the present study was to investigate the efficacy and the egg reappearance period (ERP) of ivermectin (IVM) in donkeys during a 13-week period. The study involved a total of 14 adult Amiata breed donkeys, 7 – 13 years of age, and naturally infected with small strongyles. A group of 10 donkeys was treated with IVM oral paste at a dose rate of 200 mcg/kg BW. Another group of 4 donkeys was kept as untreated control group. Faecal samples were collected and examined for strongyle eggs on day 0 before treatment. IVM efficacy was based on the faecal egg count reduction test (FECRT) on day 14 post-treatment. Then individual faecal samples were collected and examined by FECRT at weekly intervals. A FECRT of 100 % was found after treatment with IVM and its ERP, defined as the week when the mean FECRT decreased until to become lower than 90 %efficacy, was estimated to be 11 weeks without signs of developing anthelmintic resistance. No adverse reactions were observed during the study period. Our findings may be useful to veterinary practitioners and breeders as they show that IVM, at the recommended dose rate, can be still considered a highly effective and safe pharmacological tool for the treatment of small strongyles in donkeys. Therefore, it is strongly recommended that all possible strategies are undertaken to avoid the risk of emergence of anthelmintic resistance to IVM in donkeys.


Author(s):  
Yoo-Kyung Kim ◽  
Chi-Hoon Lee ◽  
Young-Don Lee ◽  
Sang-Hyun Han

The aim of the study was to develop rapid, precise and species-specific method of the identification of three grouper species (Red-spotted grouper, Epinephelus akaara; Longtooth grouper, E. bruneus; Seven-band grouper, E. septemfasciatus), by using polymerase chain reaction (PCR) mediated molecular method. A common forward primer and three different species-specific primers were designed for all the three species from the fragment of mitochondrial cytochrome c oxidase I (COI) gene. The species-specific amplification patterns showed three different bands of basepair length of had 344 bp (Red-spotted grouper), 262 bp (Longtooth grouper), and 130 bp (Seven-band grouper) which were available in the DNA samples isolated from each verified species, unknown collections, and even in mixed processed samples. Thus PCR assay provides reliable, simple, easy and low cost method for species identification of these three species of groupers.


2021 ◽  
Vol 63 (1) ◽  
Author(s):  
Evelina Dauparaitė ◽  
Tomas Kupčinskas ◽  
Georg von Samson-Himmelstjerna ◽  
Saulius Petkevičius

Abstract Background With intensive use of anthelmintic drugs in recent decades, anthelmintic resistance (AR) in horse nematodes is becoming a growing issue in many countries. However, there is little available information about the parasites, treatment practices or AR in the horse population in Lithuania. The aim of this study was to assess the current situation of AR on horse farms in Lithuania. The study was conducted in 25 stables on horses with a strongyle faecal egg count (FEC) of ≥ 200 eggs per gram. A faecal egg count reduction test (FECRT) was performed on each farm after administration of ivermectin (IVM) or pyrantel (PYR). Results The efficacy of IVM was comparatively high, with 98.8% of 250 horses having a zero egg count 14 days after treatment. Two conditions were used to interpret the FECRT results for PYR: firstly, resistance was determined when FECR was < 90% and the lower 95% confidence interval (LCL) was < 80%, and secondly when in addition the upper confidence level (UCL) was < 95%. Under the first condition, resistance against PYR was found in five stables (25% of all tested herds), while when considering the UCL as well, resistance was only detected in two stables (8%). The FEC showed a significant (P < 0.01) difference between the treatment and control groups. Only cyathostomin larvae were detected in larval cultures derived from strongyle-positive faecal samples collected 14 days after treatment of a test group with PYR. Conclusions This in vivo study showed that PYR resistance is prevalent on horse farms in Lithuania, while the efficacy of IVM still appears to be unaffected. However, further studies of ivermectin resistance are needed. These findings should guide the implementation of more sustainable management of strongyle infections in horses in Lithuania.


2021 ◽  
Vol 8 (11) ◽  
pp. 249
Author(s):  
Michal Babják ◽  
Alžbeta Königová ◽  
Ľudmila Burcáková ◽  
Michaela Komáromyová ◽  
Michaela Urda Dolinská ◽  
...  

This study was performed on a cattle farm with a long-term use of albendazole (ABZ) and a permanent history of fasciolosis for comparing in vivo and in vitro methods for the detection of anthelmintic resistance and drug efficacy. A selected group of 10 Charolais cows was treated in autumn 2020 with ABZ at a dose of 7.5 mg/kg body weight. Another group of 10 cows remained untreated as a control. The faecal egg count reduction test was used to determine in vivo efficacy. The percentage reduction of eggs on day 14 after treatment ranged from 77 to 81.8%, depending on the formula used for calculation. The in vitro egg hatch test (EHT) was used as a second diagnostic method. F. hepatica eggs for the EHT were isolated from faecal samples. The test was performed in two versions differing in the length of incubation with ABZ (12 h and 15 d). The percentage of eggs with inhibited development at a concentration of 0.5 μM in both versions of the EHT agreed with the in vivo results. Ovicidal activity at a concentration of 0.5 μM in the 12-h version suggested a reduced efficacy of ABZ (65.40%). An EHT prepared using pooled faecal samples was a prospective method for the detection of efficacy and ABZ resistance in F. hepatica.


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