Behavioral responses of Poecilia vivipara (Osteichthyies: Cyprinodontiformes) to experimental infections of Acanthocollaritrema umbilicatum (Digenea: Cryptogonimidae)

Abstract

The swimming behavior of Poecilia vivipara was evaluated using an image analysis system comparing laboratory-reared uninfected fish before and after experimental infection with different intensities of cercariae of the trematode Acanthocollaritrema umbilicatum. Two experiments were performed, each with 30 fish which were individually exposed to 30 and 50 cercariae, respectively, shed from experimentally infected molluscs, Heleobia australis. Before and after (17-27 days) infection, the behavior of each fish was monitored in terms of Distance travelled, Ambulatory time, Stereotypic time, Resting time and Average speed. At the end of the experiments, the fish were dissected to count the number of metacercariae recovered. In the experiment with 30 cercariae, fish with 2-10 metacercariae did not exhibit any significant differences in their swimming activity, but those with 11-22 metacercariae had a significantly enhanced Stereotypic time and a reduced Time Resting. In the experiment with 50 cercariae, fish with 5-22 metacercariae had an enhanced Distance travelled and a reduced Average speed; highly significant differences occurred with regard to all behavioral parameters when considering the subgroup 23-36 metacercariae: Distance travelled, Stereotypic time, Resting time, Ambulatory time and Average speed. The swimming behavior of P. vivipara changed influenced by an intensity-dependence on metacercariae of A. umbilicatum, supporting the prediction that parasites are able to alter the behavior of their hosts.

Molecular characterization and confocal laser scanning microscopic study of Pygidiopsis macrostomum (Trematoda: Heterophyidae) parasites of guppies Poecilia vivipara

“…Both of these two trematodes are considered to have zoonotic potential. The new data will support future control measures to reduce the level of parasitism in P. vivipara when reared in fish farming systems, especially for aquarium purposes, but also for fish used as a model for toxicological and behavioural studies (Santos, Cunha & Santos 2011;Harayashiki et al 2013).…”

Changes in the locomotory and reproductive behavior of Biomphalaria glabrata infected with Schistosoma mansoni

“…The image analysis biomonitoring system (IABS) was based on the use of a Videomex V ® (Columbus Instruments, Ohio, USA) using the software Travelled Distance of Multiple Objects after Magalhães et al (2007) and Santos et al (2011). The instrument includes a recording cabin made of acrylate, diffused soft lighting and an analogical video camera.…”

Does the trematode Centrocestus formosanus affect the locomotory activity of the mollusc Melanoides tuberculatus?

“…In the area of Rio de Janeiro, Brazil, the life cycles of digenean species have been elucidated in the ecosystem of the Rodrigo de Freitas lagoon [5-8] and maintained in our laboratory, enabling us to compare the swimming behaviour of an intermediate fish host before and after a digenean infection using an image analysis biomonitoring system [9]. Although the avian and fish fauna of the lagoon are well known, there are few studies on molluscs in this area [6], among which is the ‘red-rim melania’ Melanoides tuberculatus (Müller, 1774) (Thiaridae), an introduced gastropod snail which now has a wide geographical distribution throughout the Neotropics [10].…”

“…Melanoides tuberculatus infected with Centrocestus formosanus , in addition to a reduced movement, exhibited an irregular locomotory activity pattern, whereas uninfected snails had a regular pattern of locomotory activity during the biomonitoring period. A similar experiment by Santos et al [9], using a Videomex V® system, assessed the locomotory activity of fish hosts in the same lagoon, and these authors suggested that a lethargic and less motile parasitized fish is more likely to be preyed upon by the definitive host. In the case of the less motile snail host, we consider that it is more likely to influence the life cycle of C .…”

“…The image analysis biomonitoring system (IABS) used in this study is that used by Magalhães et al [9,15]. The IABS is composed of an illuminating cabin and a recording cabin made of acrylate and holding a fixed analogue video camera.…”