The effect of the bopyrid isopod Probopyrus pandalicola (Packard, 1879) (Isopoda, Bopyridae) on the survival time of the daggerblade grass shrimp Palaemonetes pugio Holthuis, 1949 (Decapoda, Palaemonidae) during starvation at two different temperatures

Abstract

The daggerblade grass shrimp Palaemonetes pugio Holthuis, 1949 is prevalent in estuaries along the East and Gulf coasts of the United States, and is an integral part of the estuarine food web. Probopyrus pandalicola (Packard, 1879) is a bopyrid isopod that parasitizes P. pugio and decreases the energy available to its host by feeding on the hemolymph of the shrimp. The parasite also causes female shrimp to be castrated. The purpose of this study was to determine the effect of Probopyrus pandalicola on the survival time of P. pugio during starvation at two different temperatures. The experiment was conducted between September 2009 and June 2012 at 20.0 ± O.irC and 25.0 ± 0.10°C. Three trials at each temperature were performed. For each trial, parasitized, deparasitized and unparasitized shrimp were randomly placed into individual aquaria in a temperature-controlled chamber. All trials lasted until 100% shrimp mortality occurred. The bopyrid isopod did have a significant effect on shrimp survival times, but only at the higher temperature during which parasitized shrimp survived a significantly shorter amount of time (21.8 ± 6.93 days) than unparasitized shrimp (25.2 ± 8.25 days). In contrast, the bopyrid did not have a significant effect on shrimp survival times at the lower temperature, with shrimp surviving an average of 26.9-27.5 days. The results of this study have implications related to potential climate change, specifically higher temperatures, as we found that a small increase in temperature significantly affected the response of P. pugio to the isopod parasite. This supports prior research on other host-parasite interactions that are affected by increased temperature. RESUME La crevette bouquet Palaemonetes pugio Holthuis, 1949 est fréquente dans les estuaires le long des côtes Est et du Golfe des Etats Unis, et elle fait partie intégrante de la chaine alimentaire. Probopyrus EFFECTS OF PROBOPYRUS INFECTION ON PALAEMONETES 1329l'énergie utilisable par son hôte en se nourrissant sur l'hémolymphe de la crevette. Le parasite provoque aussi la castration des femelles. Le but de cette étude a été de déterminer les effets de Probopyrus pandalicola sur le temps de survie de P. pugio au cours d'un jeûne à deux températures différentes. L'expérience a été conduite entre Septembre 2009 et Juin 2012 à 20,0 ± O,irC et 25,0 ± 0,10°C. Trois essais ont été effectués à chaque température. Pour chaque essai, des crevettes parasitées, déparasitées et non parasitées ont été placées au hasard dans des aquariums individuels dans une chambre à température contrôlée. Tous les essais ont duré jusqu'à la mort de 100% des crevettes. Les isopodes bopyridés ont eu un effet significatif sur les temps de survie, mais seulement à la plus haute température, pour laquelle les crevettes parasitées survivent un laps de temps plus court (21,8 ± 6,93 d [= jours]) que les crevettes non parasitées (25,2 ± 8,25 d). Par contre les bopyridés n'ont pas eu d'effet significatif sur les temps de survie des crevettes à la plus basse température, avec u...

The Effect of Temperature on Synchronization of Brood Development of the Bopyrid Isopod Parasite Probopyrus pandalicola with Molting of Its Host, the Daggerblade Grass Shrimp Palaemonetes pugio

“…In Georgia, Modeste (2009) estimated that sexual sterilization of female shrimp by bopyrids may already be causing up to a 22% loss of egg production in the population of daggerblade grass shrimp. Additionally, parasitization directly impacts host survival under starvation conditions, with parasitized shrimp surviving for less time than unparasitized shrimp at 25 C (Sherman and Curran, 2013).…”

“…The sex of the shrimp was determined by the presence or absence of the appendix masculina on the endopods of the second set of pleopods as per Anderson (1985). Only female shrimp were selected to control for differential effects of the isopod on male and female shrimp, as described by Berg (1979), John (2011), and Sherman and Curran (2015). The molt stage of each shrimp was classified based on the development of setae on the uropods, as per Walker (1984) and Promwikorn et al (2004).…”

“…Shrimp were fed fish flakes and nauplii of the brine shrimp Artemia salina, as per Key et al (2006). The water was changed every other day, similar to the procedure used by Sherman and Curran (2013), and there was no effect of water changes on when the isopod young were released (P ¼ 0.6471); brood release occurred on 44 and 50% of the days with water changes at 23 and 15 C, respectively. Six shrimp died during Trial 1 at 15 C, and 13 died during Trial 2 at 23 C. The cause of death for 9 of the shrimp in Trial 2 was most likely a result of undissolved salts added during the water change on 21 July.…”

“…Parasitization by P. pandalicola alters grass shrimp physiology (Anderson, 1975a;Walker, 1977;Ludwig, 2009;John, 2011;Sherman andCurran, 2013, 2015). Physiological effects of the parasite include sexual sterilization (Beck, 1980;John, 2011;Sherman and Curran, 2015), increased caloric intake (Anderson, 1977), decreased oxygen consumption and metabolic rate (Anderson, 1975a), and decreased growth (Ludwig, 2009). It has also been reported that this parasite affects host behavior (Bass and Weis, 1999;Brinton, 2014).…”

Variabilidad Intra-Anual en La Infestación Del Carideo Hippolyte Zostericola Smith, 1873. (Caridea: Hippolytidae) Por El Isópodo Parásito Bopyrina Abbreviata Richardson, 1904 (Epicaridea: Bopyridae) en Un Sistema Estuarino Del Sur Del Golfo De México

“…En el caso de la temperatura, se ha mencionado que este puede ser uno de los factores más importantes para explicar este patrón de variación de estos parásitos, ya que se ha encontrado que a mayores temperaturas las infecciones por isópodos bopiridos se vuelven más patogénicas (Sherman & Curran, 2013). Sin embargo, esta información contrasta con la del presente estudio, ya que las temperaturas más altas fueron registradas entre julio y septiembre.…”