Effect of dopamine injection on the hemocyte count and prophenoloxidase system of the white shrimp Litopenaeus vannamei

Abstract

Effects of dopamine injection on the hemocyte count, phenoloxidase activity, serine proteinase activity, proteinase inhibitor activity and α 2 -macroglobulin-like activity in L. vannamei were studied. Results showed that dopamine injection resulted in a significant effect on the parameters measured (P < 0.05), while no significant difference was observed in the control group (0.85% NaCl). In the experimental groups, the hemocyte count reached the minimum in 3 h; granular and semi-granular cells became stable after 12 h and hyaline cells and the total hemocyte count became stable after 18 h. Phenoloxidase activity reached the minimum in 6 h, and then became stable after 9 h. Serine protease activity and proteinase inhibitor activity reached the minimum in 3 h, and α 2 -macroglobulin-like activity reached the maximum in 3 h, and all the three parameters became stable after 12 h. The results suggest that the activating mechanisms of the proPO system triggered by dopamine are different from those triggered by invasive agents or spontaneously activated under a normal physical condition.

Development of methodology and reference intervals for the analysis of the free‐ranging Atlantic horseshoe crab Limulus polyphemus hemolymph

“…(A) The males (n = 25) showed similar results, with a total protein average of 8 g/dL, a small initial peak (14%), and a major protein in the second peak (77%.). (B) Females with low total protein (2 g/dL) showed most of the peaks 1 and 2 (46% and 42%, respectively) Hemolymph Electrophoretograms for Limulus polyphemus including arachnids (scorpions and spiders) and intermolt crustaceans (lobsters, shrimp), were of similar magnitude to cell counts in the present study: the whip scorpion, Mastigoproctus giganteus, (41.1 ± 5./µL),15 wolf spider, Schizocosa episina, (37.3 ± 3.4 SE × 10 3 / µL),22 white shrimp, Litopenaeus vannamei, (11.5 × 10 3 /µL),23 American lobster, Homarus americanus, (17 ± 1.3 SD × 10 3 /µL),24 western rock lobster, Panulirus cygnus, (15.9 ± 1.1 SE × 10 3 /µL),25 and the mud crab, Scylla tranquebarica, (26.5 ± 5.7 SD × 10 3 /µL) 26. In crustaceans, evidence that disease decreases hemocyte concentrations is based on challenge studies where moribund animals had lower values compared with healthy counterparts 26,27.…”

Effect of Modified Atmosphere with Varying O₂ Concentrations on the Quality of Packed Pacific White Shrimp (<i>Penaeus vannamei</i>) during Cold Storage

“…Pacific white shrimp (Penaeus vannamei) is one of the most popular aquatic products in China and other countries [1,2], due to its delicacy and nutritional values. However, shrimps' commercial value is easy to decline with a limited shelf life, due to microbial contamination and melanosis [3].…”