The relationships between PCO2 and pH were determined in cell-free undiluted haemolymph of the arachnids Eurypelma californicum, Pandinus imperator and Cupiennius salei. The pH/bicarbonate diagrams and the CO2 equilibrium curves were calculated, using the Henderson­Hasselbalch equation, for haemolymph sampled at rest and during recovery from exercise. The calculations of solubility (alphaCO...

Low temperature causes loss of neuromuscular function in a wide range of insects, such that the animals enter a state known as chill coma. The ability to recover from chill coma (chill coma recovery time) is often a popular phenotype to characterise chill tolerance in insects. Chill coma in insects has been shown to be associated with a decrease in haemolymph volume and a marked increase in [K(...

In the present study effects of both injections of serotonin and dopamine on haemolymph glucose, total carbohydrates, glycogen and phosphorylase activity in different tissues of intact and eyestalk ablated M.rosenbergii. The haemolymph glucose levels was increased dose dependent in between 10 and 10 mole/prawn after injection of serotonin and dopamine. While the dose 10 mole/prawn induced peak ...

oral supplementation with 50, 100 and 150 ?g/ml calcium chloride to the fifth stadium larvae of csr2xcsr4 biovoltine hybrid silkworm, b. mori on fat body glycogen, protein, and total lipids and haemolymph trehalose and protein have been studied. one of the four normal feeds per day was substituted with treated leaves fed to silkworms at fifth instar larvae. the controls were fed with the leaves...

Organismal homeostasis requires regulation of extracellular acid-base status; however, the mechanisms by which insects regulate haemolymph pH are poorly known. We evaluated the recovery of desert locusts Schistocerca gregaria Forskal from acute acid loads, initiated by HC1 injections into the haemolymph (0.5 pH unit decrease). Haemolymph pH, PCO2 and [HCO3~] recovered in 8-24h, providing the fi...

When Carcinus was exposed to 20 /i-mol I" cadmium, the haemolymph cadmium level was initially dependent upon the salinity of the external medium. After 14 days the mean haemolymph cadmium level in 50% s.w. animals was nearly twice that of 100% s.w. animals. This trend was not sustained, however, and the situation was complicated by occasional inconsistent values. In both in vivo and in vitro co...

The current study was conducted to determine the LC(50) value of ammonia-N as well as the effects of acute exposure to elevated ammonia on the haemolymph osmolality, ionic composition, ammonia-N and pH levels of early juvenile mud crabs, Scylla serrata. The results show that early S. serrata juveniles have a high 96-h LC(50) value of 95.35 mg/L ammonia-N (6.81 mg/L NH(3)-N) or 6.80 mmol/L total...

Oral Supplementation with 50, 100 and 150 ?g/ml calcium chloride to the fifth stadium larvae of CSR2xCSR4 biovoltine hybrid silkworm, B. mori on fat body glycogen, protein, and total lipids and haemolymph trehalose and protein have been studied. One of the four normal feeds per day was substituted with treated leaves fed to silkworms at fifth instar larvae. The controls were fed with the leaves...

In vivo magnetic resonance imaging (MRI) and angiography were applied to the marine spider crab Maja squinado for a study of temperature effects and thermal tolerance. Ventilation and haemolymph circulation were investigated during progressive cooling from 12°C to 2°C. The anatomical resolution of MR images from Maja squinado obtained with a standard spin echo sequence were suitable to resolve ...

Acid-toxicity tests were performed using two crayfish species, Procambarus clarki Girard and Orconectes rusticus Girard to determine the median lethal pH (LC60) after 4 days exposure to acid. Four-day LC50 values of pH 2*5-2-8 were observed, indicating that these animals are more acid-tolerant than most fish species. Haemolymph acid-base variables and major ion concentrations were measured duri...