Effects of ambient ammonia on ammonia-N and protein concentrations in hemolymph and ammonia-N excretion of Penaeus chinensis

Abstract

Individual Penaeus chinensis adults (26.91 + 4.66 g) were subjected to 0.03, 5.10,

Modulatory effects of ammonia-N on the immune system of Penaeus japonicus to virulence of white spot syndrome virus

“…In addition, exposure of shrimp to ammonia-N caused accumulation of haemolymph ammonia and urea, and caused the catabolism of haemocyanin and protein to free amino acids. This is the main reason for the decrease in plasma protein concentrations caused by high ammonia-N of water (Chen et al, 1993(Chen et al, , 1994a.…”

Haemolymph nitrogenous constituents and nitrogen efflux rates of juvenile shrimp,Penaeus paulensis(Perez-Farfante), exposed to ambient ammonia-N

“…At lower concentrations of ambient ammonia (7 mg L –1 ), the shrimp kept haemolymph ammonia‐N at levels above those of the external environment (Table 1), which would probably allow them to keep excreting ammonia‐N by simple diffusion. Penaeus chinensis exposed to 20 mg L –1 of ambient ammonia‐N for 24 h have also shown haemolymph ammonia‐N concentrations lower than ambient values, but when the shrimp were exposed to 5 and 10 mg L –1 , the influx‐induced ammonia‐N accumulation reached levels which were higher than the external concentrations (Chen et al . 1993).…”

“…Haemocyanin and total protein concentrations in the haemolymph may be altered as a result of the animals' nutritional status and of ambient salinity levels (Uglow 1969;Pequeux, Vallota & Gilles 1979;Hagerman 1983). Chen et al . (1993) and Chen et al .…”

“…Exposure to ammonia-N may depress the osmoregulatory capability of Penaeus japonicus and Homarus americanus (Young-Lai, Charmantier-Daures & Charmantier 1991;Lin et al 1993), and the addition of ammonia-N into the haemolymph of Cancer magister may reduce haemocyanin oxygen-af®nity (Sanders, Morris, Childress & McMahon 1992). Supranormal ammonia-N concentrations may also inhibit the excretion of nitrogen, as shown for several species of crustaceans (Needham 1957;Kormanik & Evans 1984;Chen, Nan, Cheng & Sheen 1993;Chen, Chen & Cheng 1994).…”

“…Ammonia is a small and highly soluble molecule which can move rapidly across most biological membranes (Schmidt‐Nielsen 1983). Influx‐induced increases in haemolymph ammonia‐N have been found to occur in crustaceans (Chen et al . 1993;Schmitt 1995;Schmitt & Uglow 1997a), but the mechanisms used by the animals to cope with such increases have received little attention to date.…”