A bivoltine silkworm hybrid, KA x NB4D2 was treated with the juvenoid R394 (Ethyl-9 cyclohexyl-3,7-dimethyl-2,4-nonadienoate) at a dose of 0.039 nl/larva at 24, 48, 72 and 96 h of 5th instar for silk yield improvement. Treatment specific significant increase was observed in the cocoon and shell weight with no such marked variation in the shell percentage. Notable changes were also seen in tr...

The pattern of metabolic changes during tethered flight with lift-generation was investigated in two South African species of long-horned beetles (family: Cerambycidae), namely Phryneta spinator and Ceroplesis thunbergi. Energy substrates were measured in haemolymph and flight muscles at rest, after a flight period of 1 min at an ambient temperature of 25-29 degrees C, and 1 h thereafter. Fligh...

The termination of discontinuous gas exchange cycles (DGCs) in severely dehydrated insects casts doubt on the generality of the hygric hypothesis, which posits that DGCs evolved as a water conservation mechanism. We followed DGC characteristics in the two density-dependent phases of the desert locust Schistocerca gregaria throughout exposure to an experimental treatment of combined dehydration ...

Wild Iceland scallops Chlamys islandica from an Icelandic bay were examined for parasites. Queen scallops Aequipecten opercularis from the Faroe Islands and king scallops Pecten maximus and queen scallops from Scottish waters were also examined. Observations revealed heavy infections of eimeriorine parasites in 95-100% of C. islandica but not the other scallop species. All life stages in the ap...

Infection by a baculovirus (Bombyx mori nuclear polyhedrosis virus, BmNPV) in silkworm (Bombyx mori) larvae is highly efficient as an expression system for the production of useful proteins. However, the amount of the protein of interest expressed tends to decrease in the later stages of infection presumably due, in part, to a proteinase produced in the larval haemolymph. The N-terminal amino a...

Oxygen equilibrium curves and the relationships between the partial pressure of CO2 and pH were determined for the haemolymph of the arachnids Eurypelma californicum, Pandinus imperator and Cupiennius salei. A new type of experimental apparatus was constructed, tested and used to make these measurements on small undiluted cell-free haemolymph samples. Most of its components were made in our wor...

Injection of trehalose into the haemolymph of Locusta nymphs reduced the amount of grass eaten in one meal. Greater effects were produced by higher concentrations and most reduction occurred when meals began 20 min after injection. Sodium chloride, glycine, proline, sorbose, inulin or a mixture of solutes had similar effects. The similarity of effects is explicable in terms of the increase in h...

Induction of haemolymph proteins in mosquito A. stephensi due to wounding or bacterial infection (E. coli) was analyzed using SDS-PAGE. Wounding response of pupa revealed subsequent induction of two polypeptides (21 and 74 kDa). Two other polypeptides (44 and 57 kDa) were induced commonly in both pupa and adult female haemolymph upon bacterial infection. In vitro binding assay revealed identifi...

Synthesis and release of vitellogenin in the crustacean Isopoda, Porcellio dilatatus, were maximal during premolt. At that time, diurnal variations occurred in the haemolymph protein level and in the synthesis and release of vitellogenin and other proteins in the haemolymph. The pattern of variations was always identical and bimodal: the minima were at dusk and at dawn when the maxima occurred ...

The ionic composition of the haemolymph was measured in fourth instar larvae of Aedes aegypti (reared in 0-30% sea water, the animals' natural salinity range). Inorganic ions and free amino acids form a substantial part of the haemolymph osmotic concentration. With increasing external osmotic pressure, there is an increase in the concentration of the amino acids, not the major inorganic cations...