RESILIENCE OF THE SHORTNOSE GUITARFISH (Zapteryx brevirostris): COMPLETE COMPENSATORY GAIN, HEMATOLOGY AND HISTOPATHOLOGY

Abstract

Compensatory gain has been used to evaluate the plasticity of species, in adverse situations such as food deprivation. The aim of the present study was to identify the type of compensatory gain achieved by the shortnose guitarfish (Zapteryx brevirostris), in situations of reduction of food resources. Three treatments were used: seven days of food deprivation and fourteen days of refeeding (T7x14); fourteen days of food deprivation and fourteen days of refeeding (T14x14); and feeding every day (TControl). Zootechnical performance, blood samples and histological samples were evaluated. We demonstrated that this species presented complete compensatory gain and that some blood parameters and histological alterations were associated with fasting.

Occurrence of Nerocila acuminata (Schiödte & Meinert, 1881) (Crustacea, Cymothoidae) parasitic on the shortnose guitarfish Zapteryx brevirostris (Rhinobatiformes, Rhinobatidae) off Brazil

“…Elasmobranchs have occasionally been reported as hosts for some parasitic species, but these data are probably due to trawl transfers (Brusca 1981, Trilles 1994. The development and mode of infection of Cymothoidae are not yet very well understood (Bakenhaster et al 2006), and the aspects of the influence of parasitism on elasmobranchs biology have been relatively little studied (Takatsuka et al 2019). Studies on elasmobranch parasites can still be considered insufficient compared to teleosts (Garner 2013, Souza et al 2020, Ota et al 2022.…”