Molecular and parasitological tools for the study ofAscaridia gallipopulation dynamics in chickens

Abstract

Experiments were first conducted to compare and evaluate different methods of Ascaridia galli larval recovery from the chicken intestine. The number of larvae recovered from the intestinal wall of chickens infected with 1000 embryonated A. galli eggs and killed 15 days post infection (p.i.) by three methods (ethylenediamine tetraacetic acid [EDTA], pepsin digestion and scraping) were compared. The EDTA and pepsin digestion were found to be the most efficient methods with no significant difference (P!0.05) in the number of recovered larvae between the two. Subsequently, three different A. galli cohorts were established using the polymerase chain reaction-linked restriction fragment length polymorphism (PCR-RFLP) technique. A 533-bp long region of the cytochrome c oxidase subunit 1 gene of the mitochondrial DNA was targeted and 22 A. galli females were allocated to three different haplotypes. The four females with the highest embryonation rate from each haplotype group (total 12 females) were selected and used to inoculate each of 12 chickens with a dose of 1000 embryonated eggs. The chickens were killed 15 days p.i. and A. galli larvae were recovered from the small intestinal wall by the EDTA method and by sieving the lumen content on a 90 mm sieve. DNA of 40 larvae from each of the three different haplotypes was extracted using a worm lysis buffer, and PCR-RFLP analysis of these larvae revealed the same haplotype as that of their maternal parent. The identification of distinguishable cohorts may be a powerful tool in population studies of parasite turnover within the animal host.

New records of three species of nematodes in Cerdocyon thous from the Brazilian Pantanal wetlands

“…However, species identification was based on molecular analysis, which was performed by establishing consensus with partial sequences of the 18S small subunit ribosomal RNA (rRNA) gene and mitochondrial gene COI. The identification based on 18S rRNA showed that the specimen shared 99% of its maximum identity with A. galli when compared with specimen number EF180058 deposited in GenBank (NADLER et al, 2007); it also shared 100% of the maximum identity with the COI gene when compared with the haplotype obtained from chickens from an organic farm in Europe (KATAKAM et al, 2010). The sequences of A. galli in the present study were submitted to GenBank under the previously established accession numbers KP982856 and KP982857 for the COI gene sequence and 18S rRNA sequence, respectively.…”

Gene expression profiles of the small intestine of village chickens from an Ascaridia galli infested environment

“…Nematodes of the genus Ascaridia are known to infect many species of birds causing fatal diseases. The small intestine is a principal target organ of A. galli infection ( Katakam et al, 2010 , Luna-Olivares et al, 2012 , Taylor et al, 2007 ). Previous study ( Fatihu et al, 1990 , Luna-Olivares et al, 2012 ) showed that most of the helminth parasites were restricted to the small intestine, particularly the duodenum where there are optimum concentrations of saline and glucose.…”

Ascaridia Galli Infection in Laying Hens and the Results of in Vitro Efficacy of Levamisole, Piperazine and Carvacrol, Whether is Necessary to Change the Deworming Protocols?

“…A. galli is the most common nematode in poultry [6,11], having a direct life cycle in the intestinal tract with a larval migratory phase into the enteric wall [13]. Penetration of the parasite into the small intestine mucosa may cause hemorrhagic to necrotic enteritis, associated with anemia and diarrhea [14].…”