Cross sectional epidemiological investigation on the prevalence of gastrointestinal helminths in free range chickens in Narsingdi district, Bangladesh

Rural poultry production in Bangladesh is mainly based on the free range or backyard poultry production system. This backyard poultry plays a vital tool for poverty alleviation as well as for empowerment of poor women of this country. However, this production system has disadvantage of susceptibility to many diseases including higher burden of parasitic infection. Therefore this cross sectional epidemiological investigation was done to determine the prevalence and distribution of gastrointestinal helminths in Narsingdi district, Bangladesh. To conduct this study a total of 150 chickens from three different villages of Narsingdi district, Bangladesh (50 chickens per village) were collected by random sampling method and killed by cervical disarticulation. Thereafter, all the chickens were necropsied and gastrointestinal tracts were examined macroscopically for the presence helminth infection. In total two nematode (Ascaridia galli, Heterakis gallinarum,) and one cestode (Raillietina spp.) were identified by post mortem examination. Raillietina spp. was detected as the most prevalent helminth species (86–92 %) followed by A. galli (70–86 %), and H. gallinarum (70–76 %) in studied villages. In some chickens petechial hemorrhage were observed in the small intestinal wall which was associated with the A. galli infection and for some birds white tiny nodules were detected in case of H. gallinarum infection. No significant difference in parasite prevalence was observed between male and female bird as well as among three studied villages (P > 0.05). We observed that most of chickens were infected with more than one species of parasites. This finding suggests that the poultry production system in rural areas of Bangladesh and the environmental conditions are very favourable for the transmission and persistence of the parasite species in rural areas of Bangladesh

The occurrence of<i>Angiostrongylus vasorum</i>in terrestrial slugs from forests and parks in the Copenhagen area, Denmark

AbstractA total of 298 slugs belonging to four species,Arion lusitanicus,A. ater,A. ater rufusandLimax maximus, were collected from six different localities within a radius of 30 km from Copenhagen and examined for naturally acquiredAngiostrongylus vasoruminfection. Overall, 28 slugs (9%) were infected, but the prevalence varied among the studied localities: Rude Forest (26%), West Amager Forest (18%), Jaegersborg Forest and Deer Park (8%), Frederiksberg Park (4%), Assistens Cemetery Park (0%) and Frederiksberg Botanical Garden (0%). Only third-stage larvae (L3) were recovered from the slugs, in numbers ranging from 1 to 392 per slug. Overall 82% of the infected slugs harboured fewer than 10 larvae and only 14% harboured over 100 larvae.</jats:p

Acquisition of resistance after continuous infection with <i>Ascaridia galli</i> in chickens

SUMMARYAcquired resistance against Ascaridia galli infection was studied in seventy-two 18-week-old white Leghorn chickens allocated to six groups (G1–G6). In order to understand the population dynamics following trickle-infection (100 eggs per chicken twice weekly), chickens of subgroups of G1 were necropsied 3 days after 1, 6 or 12 inoculations (G1A, G1B and G1C respectively), while G2–G4 were inoculated for 6 weeks. G2 was necropsied 4 weeks after the last inoculation. The number of established larvae increased initially (between G1A and G1B) but decreased after repeated inoculations (G1C, G2). G3, G4 and G5 were used to measure the efficacy of anthelminthic treatment and to monitor the acquisition of resistance following a challenge infection. At week 7 G3, G4 and G5 were treated with flubendazole for 7 days in the feed. Two weeks after treatment the chickens in G4 and G5 were challenged with 500 eggs. G6 was left as uninfected control. Necropsy at week 10 after first inoculation revealed a lower establishment rate, an impaired development and a more posterior localization of the larvae in G4 (trickle-infected-treated-challenged) compared with G5 (treated-challenged). IgY level in serum reached noticeable level at 14 dpi in G2 and G4 chickens, and in G4 chickens IgY level further increased after challenge infection. The study provides evidence that acquired resistance against A. galli in chickens leads to a significant yet incomplete protection against re-infection.</jats:p

Larval development of Angiostrongylus vasorum in the land snail Helix aspersa

The metastrongyloid nematode Angiostrongylus vasorum affects the heart and pulmonary arteries of dogs and wild animals. Over the recent years, dog angiostrongylosis has gained great attention in the veterinary community for the expansion of its geographic range and for a rise in the number of clinical cases. Global warming, changes in phenology of mollusc intermediate hosts and movements of wild reservoirs have been evocated in the spreading of mollusc-borne parasites, including A. vasorum. The land snail Helix aspersa, a vector of other respiratory metastrongyloids, is endemic in most regions of the World, where it is a pest outside its native Mediterranean range. In the present study, the susceptibility and suitability of H. aspersa as an intermediate host of A. vasorum were investigated along with the characteristics of larval recovery and development following two different ways of inoculation, i.e. experimental (group A) vs natural infection (group B). After infections, the snails were kept at environmental conditions for 2 months. Five snails from groups A and B were randomly selected, digested and examined at 15-day intervals for 2 months. L1s, L2s and L3s were microscopically identified based on key morphological and morphometric characteristics and their identity was genetically confirmed. The results showed that A. vasorum may reach the infective stage in H. aspersa and that uptake of larvae and parasitic burden within the snails depend on the grazing capability of the molluscs. Biological and epidemiological implications are discussed