Levels of phenoloxidase (Po), trypsin and lysozyme activities were determined following 48 hours exposing freshwater crayfish (Pontastacus leptodactylus) weighing 59.8&plusmn;3.4g to different low pH values of 6.5, 5.5, 4 and 2.5 at 20-23˚C. Significant decrease were found (p<0.01) in levels of Po and trypsin activities in crayfish haemocyte lysate supernatant (HLS) at pHs 5.5 and 4 compared to...

The cellular and humoral immune reactions in haemolymph of the wax moth Galleria mellonella larvae naturally injected by venom of ectoparasitic wasp Habrobracon hebetor were analyzed. A strong decline of phenoloxidase (PO) activity in the haemolymph and the number of haemocytes with PO activity of envenomated wax moth was observed. In addition, it has been shown that the rate of capsule melaniz...

39 Phenoloxidase (PO) is believed to be a key mediator of 40 immune function in insects and has been implicated both in 41 non-self recognition and in resistance to a variety of 42 parasites and pathogens, including baculoviruses and para43 sitoids. Using larvae of the Egyptian cotton leafworm, Spo44 doptera littoralis, we found that despite its apparent impor45 tance, haemolymph PO activity va...

Pheromones function not only as mate attractors, but they may also relay important information to prospective mates. It has been shown that vertebrates can distinguish, via olfactory mechanisms, major histocompatibility complex types in their prospective mates. However, whether pheromones can transmit information about immunocompetence is unknown. Here, we show that female mealworm beetles (Ten...