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were 20 days shorter than under E. This indicates that particle size 

 of the medium is critical. Larvae reared on coarse diets have 

 difficulty chewing the large particles and, consequently, are 

 undernourished and suffer high mortality. The extra moisture in diet 

 E caused packing of the food material, making it difficult to chew, 

 and encouraged excessive mold growth, which entrapped some early 

 instars. It is interesting to note that even development times of the 

 nonfeeding egg and pupal stages were significantly longer under diet E 

 than under any of the other regimens. Excessive moisture may retard 

 development, at least during the egg stage, and undernourishment in 

 the larval stage may result in a prolonged pupal stage. 



The addition of liver powder to regular sand fly diet (diet B) 

 resulted in little change in development time but caused a 

 significant increase in mortality (ANOVA PR>F = 0.0001; Duncan's 

 multiple range test, a = 0.05). The liver powder introduced 

 undesireable fungal growth which proved deleterious to the larvae. 

 Kil 1 ick-Kendrick _et aj_. (1977) fed Lu . longipalpis larvae on 

 dessicated liver powder alone, with good results, but commented that 

 overfeeding with liver powder encouraged growth of fungi, which is a 

 danger to younger larvae. 



Diets C and D (incubated and unincubated horn fly medium, 

 respectively) produced about equal results, reducing the total 

 immature development time by 6 to 27 days, with an accompanying 

 increase in the number of individuals surviving to the adult stage. 

 Both of these diets have been used in the laboratory colony since the 

 13th generation. As a result, the duration of the larval stage has 

 been reduced substantially from a mean of 45 days in the 9th 



