RESUMEN
1. The optimal level of sodium in an artificial diet for the house cricket was found to be 1126 ppm, of potassium 6487 ppm and of calcium 1366 ppm. 2. The revised salt mixture for the house cricket is 68.02 g NaCl, 120.00 g KCl, 310.00 g KH2PO4, 37.65 g CaHPO4, 53.34 g CaCO3, 90.50 g MgSO4.7H2O, 14.70 g FePO4.4H2O, 0.23 g MnSO4.H2O, 0.55 g ZnCO3 and 0.72 g CnSO4 in a total of 695.71 g salts.
Asunto(s)
Calcio , Dieta , Gryllidae , Potasio , Sodio , Animales , Gryllidae/crecimiento & desarrollo , Larva , ÓvuloRESUMEN
Frass of late-instar larvae ofTenebrio molitor L. contained 0.0889 g of butyric acid, 0.0279 g of propionic acid, and 0.0175 g of valeric acid per 100 g. Grouped larvae were strongly repelled by butyric acid at the 10(-1) M concentration. Lower concentrations of butyric acid were less repellent. Valeric acid was repellent at 10(-1) M to 10(-3) M concentrations, below which no tested concentration, including one identical to that occurring in prepared solutions of frass found to be attractive, displayed any effect. Propionic acid was repellent at the concentration in prepared solutions of frass, which were strongly attractive. Concentrations of 10(-1) M, 10(-3) M, and 10(-4) M propionic acid were also found to be repellent. The implications of the repellency of these compounds to groups of mealworm larvae are discussed, with particular reference to the interaction between these frass components and others that have already been studied.
RESUMEN
Late-instar larvalTenebrio molitor L. were found to be attracted to aqueous extracts of conspecific larval frass. The attraction was evident at both the individual and group level. The attraction of larval groups to frass indicated the possibility of an aggregation pheromone that would be chemically distinct in the mealworm environment. Chemical analysis of short carbon chain acids present in both the mealworm frass and the diet indicated that lactic acid was present in the mealworm frass only. Acetic acid was identified in both the diet and the larval frass. Larvae aggregated on filter papers treated with aqueous frass extracts that had been dried and also on those freshly wetted. The larvae also aggregated on dried or freshly wetted papers treated with lactic acid, but failed to aggregate on freshly wetted papers or dried papers treated with acetic acid. The role of excreted lactic acid as a discriminant of already infested and, therefore, safer environmental regions is discussed.
RESUMEN
Evaluation of the lactic acid attraction of individual and grouped larvalTenebrio molitor L. in an olfactometer indicated that olfaction is unlikely to be the chemoreceptive mode governing substrate choice or aggregation of these insects. High-magnification videotaped sequences of mealworms on treated and control filter papers indicated that larvae sample the substrate by rapidly probing with mouthpart palpi in a manner similar to the leaf sampling of certain caterpillars. The reception of lactic acid stimuli may therefore involve contact chemoreceptors. The larvae frequently touch each other in a similar manner. Bioassays comparing the cumulative frequencies of distributions of mealworms on control and lactic acid-treated filter papers indicated significant differences, with higher density clusters being found on the treated papers. Comparison of the control distribution with the expected distribution revealed an innate tendency to aggregate. The implications of these results are discussed with regard to the formation of mealworm clusters in the environment.
RESUMEN
Young larvae of Periplaneta americana (L.) are attracted to filter paper wetted with 10(-2)-10(-3)% solutions of butyric acid. Other volatile fatty acids and lactic acid, as well as other organic and inorganic acids, are repellent to larvae at high concentrations, and ineffective at low.
Asunto(s)
Cucarachas/fisiología , Ácidos Grasos Volátiles/farmacología , Lactatos/farmacología , Periplaneta/fisiología , Envejecimiento/fisiología , Animales , Conducta Animal/efectos de los fármacos , Cromatografía de Gases , Ácido Láctico , LarvaRESUMEN
Lactic acid has been identified in extracts of filter paper "conditioned" by the German cockroach,Blattella germanica (L.). One-to two-week old larvae aggregated on filter paper wetted with solutions of lactic acid.
RESUMEN
The frass of the following omnivorous insects reared on natural and artificial diets was analyzed for volatile fatty acids:Blattella germanica, Acheta domesticus, Blaberus discoidalis. Acetic, propionic, isobutyric, butyric, isovaleric, and valeric acids were identified in all frass samples. The possible significance of volatile fatty acids in frass is discussed.
RESUMEN
Two- to 12-day-old larvae ofBlattella germanica are repelled by certain volatile fatty acids present in the frass. Propionic, isovaleric, and valeric acids are strongly repellent, isobutyric acid is slightly repellent, and acetic and butyric acids are without effect. These results are discussed in relation to control of population density.