Stress-Induced Changes in Cell Titer of Crayfish Hemolymph

Abstract

Cell titer in peripheral hemolymph of crayfishes rises in less than one hour after administration of stress. The stress may be wounding or handling of the animals.

Variation of antibacterial activity in the haemocytes of the shore crab,Carcinus maenas, with temperature

“…This may be a consequence of the unavoidably small sample sizes used in this investigation. Wide variation in total haemocyte counts between individual animals has been noted for crustaceans by several workers (Hamann, 1975;Smith et ah, 1984;Smith & Johnston, 1992). Also, for a phenomenon as powerful as bacterial killing , the subtle differences between SI values of, for example, 01 and 001 (representing an effectiveness of 99-90% and 99-99% respectively) are perhaps less critical than the clear differences seen in February and August.…”

Potential utility of haemolymph analysis in non-lethal conservation studies on threatened Australasian freshwater crayfish : portability and practicality

“…These methods might offer substantial advantages over existing techniques, because only small volumes of haemolymph are required (e.g., ~25-300 µL per test) and the small-gauge needles used are minimally intrusive (e.g., 26G needle, 0.45 mm Ø). Repetitive sampling over time is unlikely to be lastingly injurious or lethal to specimens (Hamann, 1975;Paterson et al, 1997), although the possibility for adverse side effects (i.e., infection) cannot be absolutely excluded. Furthermore, as haemolymph constitutes ~30% of a crayfishes biomass (marine species, see Belman, 1975) and total volume can be quickly adjusted through biological functions (Greco et al, 1986), these methods are suitable for use on rare and endangered species.…”