Feeding and osmoregulation in the euryhaline crab Neohelice granulata: digestive parameters responses

MENDEZ, E.; MENDEZ, E.; LÓPEZ MAÑANES, A,A.; LÓPEZ MAÑANES, A,A.; PINONI,S.A.; PINONI,S.A.

ANIMAL BIOLOGY

BRILL ACADEMIC PUBLISHERS

Lugar: Leiden; Año: 2019 vol. 69 p. 433 - 449

1570-7555

When a species often experiences variation in its environmental conditions, metabolic flexibility isrequired. We studied the duration of the digestive cycle and the activity of key digestive enzymes(proteolytic, amylase, lipase) at short and long times after feeding in the hepatopancreas of the osmoregulatorcrab Neohelice granulata from the Mar Chiquita coastal lagoon (Buenos Aires Province,Argentina). We compared these responses upon hyper-regulation and under osmoconformation conditions(10 and 35 psu). The results show the ability of this crab to hyper-regulate in different feedingstates. No significant differences were observed in the duration pattern of the digestive cycle betweenhyper-regulation and osmoconformity. However, distinct responses after feeding were observed in theactivities of the digestive enzymes studied in relation to the osmoregulatory state. In individuals exposedto 35 psu, proteolytic activity was higher at 8 h and remained constant until 72 h after feeding.At 10 psu, this activity was higher at 48 h after feeding than before feeding. At 35 psu, the amylaseactivity after feeding was greater than the prefeeding activity. No differences were observed in theactivity of lipase at 35 psu, but at 10 psu this activity was lower 1 h after feeding than before feeding.This work constitutes a contribution to our knowledge of the physiology of crustaceans and attemptsto clarify the possible mechanisms of digestive settings associated with hyper-regulation