Effect of different temperatures on survival and development of Aelurostrongylus abstrusus (Railliet, 1898) larvae

Aim of the study was to get in-depth information on Aelurostrongylus abstrusus first-stage larvae (L1s) survival at different temperatures and to assess the capability of these larvae to develop into the third infective stage (L3s). Faeces of a naturally infected cat were split into two aliquots: the first was divided in subsamples assigned to four groups (F1-F4); from the second aliquot, L1s were extracted by Baermann technique, suspended in water and divided into four groups (W1-W4). Groups were stored at different temperatures (F1/W1 -20 ± 1°C; F2/W2 +4 ± 1°C; F3/W3 +14 ± 1°C; and F4/W4 +28 ± 1°C) and L1s vitality assessed every seven days. The capability of L1s stored in water to develop into L3s in snails was evaluated at the beginning and every 21 days. The L1s of W2 and F2 groups remained viable for a longer period (231 and 56 days, respectively) compared to those of other groups. The capability of L1s to moult into L3s in snails showed a decreasing trend; the group W2's L1s maintained the capability to moult into L3s for the longest time (day 189) compared to the other groups. The time of survival of A. abstrusus L1s is influenced by temperature. However, the species seems to be more resistant to temperature variations than other feline lungworms, and this may explain its wider distribution across Europe.