The effects of gastrointestinal nematode infections and anthelmintic treatment on milk yields was compared between flocks with a low level (LL) of eggs per gram (epg) before partum and with a high level (HL). Faecal egg count reduction tests (FECRTs) were carried out before partum comparing a treated group with netobimin with an untreated group. Ewes belonging to LL flocks produced 55.
View Article and Find Full Text PDFGastrointestinal nematodes (GIN) infections are a serious problem in livestock production due to the great economic losses they cause. Their control is increasingly difficult because of the rapid development of drug resistance and the limited number of available drugs. Therefore, this study evaluated 18 aminoalcohol and 16 diamine derivatives against eggs, first and third stage larvae from a susceptible and a resistant isolate of Teladorsagia circumcincta collected from sheep.
View Article and Find Full Text PDFThis study describes early immunological mechanisms that underlie resistance to Teladorsagia circumcincta infection in adult Churra sheep. After a first experimental infection, 6 animals were classified as resistant (RG) and 6 as susceptible (SG) to T. circumcincta infection based on their cumulative faecal egg count (cFEC) at the end of the infection.
View Article and Find Full Text PDFGastrointestinal nematode infections are the main diseases in herds of small ruminants. Resistance to the main established drugs has become a worldwide problem. The purpose of this study is to obtain and evaluate the in vitro ovicidal and larvicidal activity of some 2-phenylbenzimidazole derivatives on susceptible and resistant strains of Teladorsagia circumcincta.
View Article and Find Full Text PDFBackground: Benzimidazole resistance is associated with isotype-1 β-tubulin gene F200Y, E198A and F167Y SNPs. In this study, the recently described polymorphism E198L was reported and analysed in Teladorsagia circumcincta.
Methods: The benzimidazole phenotypic resistance was measured by the faecal egg count reduction test (FECRT) and the egg hatch test (EHT) using a discriminating dose (DD) in 39 sheep flocks.
The present study was conducted to evaluate the in vitro anthelmintic activity and safety of methanolic and aqueous extracts of 9 plants against the ovine GIN Teladorsagia circumcincta. Initially the ovicidal efficacy of all extracts was tested at 50 mg/ml and at 1%, this last concentration for the methanolic extract of Elettaria cardamomum, by the Egg Hatch Assay. In those extracts with efficacy higher than 95%, the effective concentration required to inhibit 50% of egg hatching (EC) and their cytotoxicity, as the lethal dose 50 (LC), was also measured.
View Article and Find Full Text PDFBackground: Benzimidazole (BZ) resistance in gastrointestinal nematodes is associated with a single nucleotide polymorphism (SNP) at codons 167, 198 and 200 in the isotype 1 of beta-tubulin gene although in some species these SNPs have also been associated with resistance to macrocyclic lactones. In the present study we compared the levels of resistance in Teladorsagia circumcincta and Trichostrongylus colubriformis by means of the faecal egg reduction test (FECRT) and the percentage of resistant alleles obtained after pyrosequencing. The study was conducted in 10 naturally infected sheep flocks.
View Article and Find Full Text PDFBackground: Loop-mediated isothermal amplification (LAMP) is a very specific, efficient, and rapid gene amplification procedure in which the reaction can run at a constant temperature. In the current study we have developed a LAMP assay to improve the diagnosis of Fasciola spp. in the faeces of sheep.
View Article and Find Full Text PDFBackground: In the present study, the detection of anthelmintic resistance to triclabendazole (TCBZ) in sheep infected by Fasciola hepatica was studied using an egg hatch assay (EHA). F. hepatica eggs were recovered from bile and faeces of infected animals by isolates with different grade of anthelmintic resistance to TCBZ: i) a resistant isolate (RT); ii) a susceptible isolate (ST); iii) naturally infected sheep by a susceptible field strain (FST).
View Article and Find Full Text PDFIn the current study, Fasciola hepatica strains of sheep with different degrees of resistance to anthelmintics were analyzed by sequencing the cytochrome C oxidase (COX1) and the NADH dehydrogenase (NAD1) subunits. The strains were as follows: LS, susceptible to all drugs tested; CS, resistant to albendazole and triclabendazole; and SV, resistant to albendazole and clorsulon. The molecular characterization was done in eggs recovered from sheep infected by LS and CS.
View Article and Find Full Text PDFParasit Vectors
September 2013
Background: In the present study we studied and updated the prevalence of the infections caused by gastrointestinal nematodes (GIN) and Fasciola hepatica in grazing sheep in the northwest (NW) of Spain for the last six years (2006-2011), and its relationship with the current climatic conditions.
Methods: We analyzed faecal samples from 110 flocks located in four different provinces of the Autonomous Community of Castilla y León: 76.4% of them were situated in León, 12.
A telephone survey of farmers was conducted to determine current internal parasite control practices on sheep farms in Spain; the farmers were interviewed by their veterinarians. Anthelmintic choice was largely on veterinary advice and dominated by benzimidazoles and macrocyclic lactones. Anthelmintic rotation was separated into: no rotation (42% of farms); annual rotation (36%); rotate within year (20%); and rotate every second year (2%).
View Article and Find Full Text PDFIndividual mutations (e.g. L256F) and polymorphisms in the avr-14B gene, a glutamate-gated chloride channel subunit, have been associated with ivermectin (IVM) resistance in Caenorhabditis elegans and Cooperia oncophora.
View Article and Find Full Text PDFCystic echinococcosis (CE) remains an important health problem in many regions of the world, both where no control measures have been implemented, and where control programs have been incompletely successful with ensuing re-emergence of the disease. In Spain, official data on CE show an increase in the proportion of intermediate hosts with CE during the last few years, and autochthonous pediatric patients have been reported, a sign of active local transmission of disease. A similar picture emerges from data reported to the European Food Safety Authority by other European countries.
View Article and Find Full Text PDFThe aim of this study was to compare the efficacy of triclabendazole (TCBZ) and nitroxynil against a TCBZ-resistant Fasciola hepatica strain in a naturally infected sheep flock. The efficacies were measured by the faecal egg count reduction test. The level of F.
View Article and Find Full Text PDFIn this study we have investigated the prevalence of aelurostrongylosis, one of the most common feline pulmonary parasitic diseases, in cats from the north-west region of Portugal. For this purpose, 97 faecal samples were collected from cats at risk of being infected by Aelurostrongylus abstrusus in an animal shelter and in a municipal facility. Using the Baermann-Wetzel coprological technique, faecal shedding of first stage larvae (L1) was detected in 17.
View Article and Find Full Text PDFCryptosporidium parvum is an intracellular protozoan parasite that causes severe infection in humans and animals. The great difficulties in treating people and animals suffering from cryptosporidiosis have prompted the development of in vitro experimental models. The aim of this study was to demonstrate that C.
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