<b>Seasonal shifts in the feeding of <em>Pimelodella</em> cf. <em>gracilis</em> (Osteichthyes, Siluriformes, Pimelodidae) in Amambai River, Mato Grosso do Sul State</b> - DOI: 10.4025/actascibiolsci.v28i2.1028

Abstract

The aim of this study is to describe the diet and the feeding activity of Pimelodella cf. gracilis in Amambai river, Mato Grosso do Sul State, Brazil, along the four seasons of the year. For this, the stomach contents of 232 individuals were analyzed and their Stomach Fullness Index was calculated. The results indicate that this species is omnivorous and generalist, so it consumes feeding items of several origins, such as plant material, terrestrial and aquatic insects, mollusks, fish scales, sediments and non-identified material. Notwithstanding this, the plant material was predominant in the diet along the whole year, indicating that Pimelodella cf. gracilis tends to herbivorous habit. The composition of the basic diet changed seasonally, so we observed that allochthonous items have their importance increased in the warm and rainy seasons. Besides this, we also observed seasonal shifts in the feeding activity, probably due to climactic (temperature and precipitation) and physiological factors (reproductive cycle).