The effect of temperature and host age on the infectivity and development of Angiostrongylus vasorum in the slug Arion lusitanicus

Abstract

Experimental infection with Angiostrongylus vasorum was conducted in Iberian slugs Arion lusitanicus. Initially, different size/age groups of juvenile slugs (small, <0.5 g and medium, 0.5-1 g) were exposed to freshly isolated first-stage parasitic larvae (L1) of A. vasorum. The slugs were subsequently incubated at 5, 10 and 15 degrees C for 6 weeks. Larval development within the slugs differed significantly with temperature. At 15 degrees C, all larvae developed into the third larval stage (L3), at 10 degrees C into the second stage (L2), whereas no development was observed at 5 degrees C. The mean larval burdens were highest in the largest group of slugs and tended to increase with higher temperature. In a second experiment isolated L1 were incubated at 5, 10 and 15 degrees C for 3 and 7 days prior to infection of slugs, which then were kept for 6 weeks at 15 degrees C. The infectivity decreased significantly with the larval storage time and the mean larval burden per slug was lower at higher incubating temperature. However, all established larvae developed into infective L3. Temperature had an effect on the development of the larvae and thus an impact on transmission of the parasite as only L3 are infective to the definitive canid hosts.

Infections with cardiopulmonary and intestinal helminths and sarcoptic mange in red foxes from two different localities in Denmark

“…The majority of the examined foxes in this study (94.8% of 116) and in Norway (95.4% of 174; Davidson et al 2006) were infected with cardiopulmonary nematodes, whereas lower prevalence of cardiopulmonary nematodes were reported in other European countries, for example 73.7% in Catalonia (Manas 2005) and 7.3% in Great Britain (Morgan et al 2008). Most of the currently recovered cardiopulmonary nematodes are transmitted via invertebrate hosts, which are highly dependent on optimum environmental conditions (Gortazar et al 1998;Ferdushy et al 2010), host feeding habits, season and host aggregation (Rajkovic-Janje et al 2002;Davidson et al 2006;Saeed et al 2006) for its development and ability to transmit infective larvae to the final host. The currently observed increase in the prevalence and abundance of A. vasorum among foxes compared to previous studies in Denmark (Guildal and Clausen 1973;Bolt et al 1992;Willingham et al 1996;Saeed et al 2006) might be related to the increase in the abundance of snails in the currently studied area (Ferdushy et al 2009).…”

Angiostrongylus vasorum: the ‘French Heartworm’

“…Inside the gastropod host, the larvae moult twice and develop into an infective third stage larva (L3; Rosen et al 1970;Ferdushy et al 2010).…”

Survival of first stage larvae (L1) of Angiostrongylus vasorum under various conditions of temperature and humidity

“…The intermediate host stage of metastrongyloid nematodes depend on the temperature and humidity for their development and survival (Forrester and Senger 1963;Lankester and Anderson 1968;Hansson 1974;Shostak and Samuel 1984;Lorentzen and Halvorsen 1986). The present study demonstrated that like other Angiostrongylus species, the survival of A. vasorum L1 is also temperature dependent and is promoted by cooler temperature (Sawabe and Makiya 1995;Jeffery et al 2004;Morgen et al 2009;Ferdushy et al 2010). Sawabe and Makiya (1995) studied the survival of Angiostrongylus cantonensis and Angiostrongylus malaysiensis at different temperature ranging from 4°C to 50°C in 0.75% saline solution and seen that after 24 h less than 50% of the L1 survived when the temperature reached around 40°C and almost all the larvae died at 50°C.…”

“…Abiotic factors such as temperature, humidity, precipitation as well as biotic factors such as the presence of definitive and intermediate hosts all play an important part in the continuation of the life cycle of A. vasorum (Taubert et al 2009;Morgen et al 2009;Ferdushy et al 2009Ferdushy et al , 2010Barutzki and Schaper 2009). However, very little research has been done on the part of the A. vasorum life cycle, which involves the survival of the first stage larvae (L1) in the excreted dog/fox faeces.…”