Validation of Acrylic Paint as a Marking Technique for Examining Mating Success of the Black Soldier Fly (Diptera: Stratiomyidae)

2020 ◽  
Vol 113 (5) ◽  
pp. 2128-2133
Author(s):  
Brittny M Jones ◽  
Jeffery K Tomberlin

Abstract The black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), is mass produced worldwide for use in waste management and the production of an alternative protein for use as feed. However, few publications have explored its adult behavior, particularly mating, as a means to optimize egg production in colony. In addition, there is limited knowledge of appropriate marking techniques to explore the mating behavior of this insect. The goal of this study was to validate water-based acrylic paint pens as a possible marking tool for behavioral studies with adult black soldier flies. Adult black soldier flies (<24-h old) were marked with green, gold, red, or white acrylic paint. Adult longevity, as well as the number of matings (mating success) were recorded for each treatment. Regardless of marking, 1) adult females lived ~7 d, whereas males lived 9 d, 2) mating frequency peaked 2 d after initiation of the experiment, 3) approximately 30% of adults across treatments were recorded mating, and 4) egg production and hatch rate were not affected. This marking technique did not affect the parameters measured, suggesting that it is suitable for experiments requiring a reliable marking technique.

2020 ◽  
pp. 1-16
Author(s):  
B.M. Jones ◽  
J.K. Tomberlin

Body size is a recognised factor impacting mating success of a number of insect species. The black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), which is mass produced to convert organic waste to protein, exhibits a lekking behaviour necessary for mating. However, it is not known if adult body size impacts mating success and subsequent fertile egg production. In this study, larvae were raised at two densities to produce two size classes of adults (i.e. large and small). Hourly mating observations were recorded in the following studies: (1) homogenous populations of large or small adults; (2) 50% heterogenous populations (equal number of large males with small females and vice versa); and (3) 25% heterogenous (i.e. equal number of large and small adults for both sexes). Adult weight, morphometrics of resulting adults, total number of mating pairs and failed mating attempts, multiple matings, as well as eggs produced and associated hatch rate were recorded for each experiment. Morphometrics and weights in large adults were 21 and 50% greater than small adult males and females by size and weight, respectively. The first experiment of homogenous populations (i.e. large or small) showed no significant differences across other variables measured. However, when populations of different sized adults were mixed equally based on sex (i.e. 50% heterogenous populations), mating success increased 50 to 100% for small males with large females and large males with small females, respectively. Total number of multiple matings increased two to three times. Egg production decreased 15-20% and hatch rate declined approximately 10%. In the 25% heterogenous populations, data were more complex. Number of successful mating pairs across male size was 280% greater than in the homogenous populations. Number of failed mating attempts was also two to three times greater. Multiple matings overall were low (10%) for the homogenous and heterogenous populations. Large males demonstrated two times more aggression in general than small males in the heterogenous than the homogenous populations. Approximately 48 to 343% more eggs were produced in the 25% heterogenous population than large or small homogenous populations, respectively, while hatch rate did not differ among heterogenous and homogenous populations, with an average of 70%. However, the variability in egg hatch was forty times greater than the large homogenous and 40% greater than the small homogenous. While increased egg production is desired, high variability in egg hatch impedes fertile egg production and predictability at an industrial scale.


Genetics ◽  
1998 ◽  
Vol 150 (1) ◽  
pp. 129-155 ◽  
Author(s):  
David Gems ◽  
Amy J Sutton ◽  
Mark L Sundermeyer ◽  
Patrice S Albert ◽  
Kevin V King ◽  
...  

Abstract The nematode Caenorhabditis elegans responds to overcrowding and scarcity of food by arresting development as a dauer larva, a nonfeeding, long-lived, stress-resistant, alternative third-larval stage. Previous work has shown that mutations in the genes daf-2 (encoding a member of the insulin receptor family) and age-1 (encoding a PI 3-kinase) result in constitutive formation of dauer larvae (Daf-c), increased adult longevity (Age), and increased intrinsic thermotolerance (Itt). Some daf-2 mutants have additional developmental, behavioral, and reproductive defects. We have characterized in detail 15 temperature-sensitive and 1 nonconditional daf-2 allele to investigate the extent of daf-2 mutant defects and to examine whether specific mutant traits correlate with each other. The greatest longevity seen in daf-2 mutant adults was approximately three times that of wild type. The temperature-sensitive daf-2 mutants fell into two overlapping classes, including eight class 1 mutants, which are Daf-c, Age, and Itt, and exhibit low levels of L1 arrest at 25.5°. Seven class 2 mutants also exhibit the class 1 defects as well as some or all of the following: reduced adult motility, abnormal adult body and gonad morphology, high levels of embryonic and L1 arrest, production of progeny late in life, and reduced brood size. The strengths of the Daf-c, Age, and Itt phenotypes largely correlated with each other but not with the strength of class 2-specific defects. This suggests that the DAF-2 receptor is bifunctional. Examination of the null phenotype revealed a maternally rescued egg, L1 lethal component, and a nonconditional Daf-c component. With respect to the Daf-c phenotype, the dauer-defective (Daf-d) mutation daf-12(m20) was epistatic to daf-2 class 1 alleles but not the severe class 2 alleles tested. All daf-2 mutant defects were suppressed by the daf-d mutation daf-16(m26). Our findings suggest a new model for daf-2, age-1, daf-12, and daf-16 interactions.


2020 ◽  
pp. 1-12
Author(s):  
K.B. Barragan-Fonseca ◽  
G. Gort ◽  
M. Dicke ◽  
J.J.A. van Loon

Protein (P) and carbohydrate (C) concentrations present in food affect larval performance, larval body nutrient concentration, and fecundity of the black soldier fly (BSF). We substantially expanded the range of dietary P- and C-concentrations investigated thus far to assess the effects of nutritionally – unbalanced diets on BSF larval and adult life-history traits, and on larval body protein and lipid concentrations. Twenty five artificial diets varying in their P- and C-concentration and ratio were formulated. We tested five macronutrient (P+C) concentrations (5, 15, 25, 50 and 75%) and five P:C ratios (1:1, 1:2, 1:4, 2:1 and 4:1). BSF performance was affected by P+C-concentration rather than by P:C ratios. A P-concentration between 10 and 15% and a C-concentration between 10 and 60% supported high larval and adult performance. P-concentration is limiting for most of the performance variables, however, a P-concentration higher than 37% reduced larval survival. C-concentration affected egg production more strongly than P-concentration. Overall, at P+C values of 25 and 50%, and P:C ratios 1:2 and 1:4 resulted in the highest values of most of the larval and adult performance variables we measured. For the protein and carbohydrate sources tested, dietary macronutrient concentrations significantly affected larval and adult performance of BSF in different ways. These results show a remarkable degree of nutritional plasticity, and point to the relevance of differentiating the formulation of diets to achieve maximal larval yield, high body protein or high body lipid accumulation or high adult emergence and egg production.


Author(s):  
Zhongyi Liu ◽  
Adriana J. Najar-Rodriguez ◽  
Maria A. Minor ◽  
Duncan I. Hedderley ◽  
Patrick C.H. Morel

2020 ◽  
Author(s):  
Angela Koh ◽  
Shijie Tao ◽  
Goh Yun Jing ◽  
Vindhya Chaganty ◽  
Kelvin See ◽  
...  

Abstract Neurexins are presynaptic transmembrane proteins that control synapse activity and are risk factors for autism spectrum disorder (ASD). Zebrafish, a popular model for behavioral studies, has six neurexin genes, but their functions in embryogenesis and behavior remain largely unknown. We have previously reported that nrxn2a is aberrantly spliced and specifically dysregulated in motor neurons (MNs) in models of Spinal Muscular Atrophy (SMA). In this study, we generated nrxn2aa−/− mutants by CRISPR/Cas9 to understand nrxn2aa function at the zebrafish neuromuscular junction (NMJ) and to determine the effects of its deficiency on adult behavior. Homozygous mutant embryos derived from heterozygous parents did not show obvious defects in axon outgrowth or synaptogenesis of MNs. In contrast, maternal-zygotic (MZ) nrxn2aa−/− mutants displayed extensively branched axons and defective MNs, suggesting a cell-autonomous role for maternally provided nrxn2aa in MN development. Analysis of the NMJs revealed enlarged choice points in MNs of mutant larvae and reduced co-localization of pre- and post-synaptic terminals, indicating impaired synapse formation. Severe early NMJ defects partially recovered in late embryos when mutant transcripts became strongly upregulated. Ultimately, however, the induced defects result in muscular atrophy symptoms in adult MZ mutants. Zygotic homozygous mutants developed normally but displayed increased anxiety at adult stages. Together, our data demonstrate an essential role for maternal nrxn2aa in NMJ synapse establishment, while zygotic nrxn2aa expression appears dispensable for synapse maintenance. The viable nrxn2aa−/− mutant furthermore serves as a novel model to study how an increase in anxiety-like behaviors impacts other deficits.


1990 ◽  
Vol 83 (6) ◽  
pp. 2306-2309 ◽  
Author(s):  
Nancy C. Hinkle ◽  
Philip G. Koehler ◽  
Richard S. Patterson

1997 ◽  
Vol 54 (3) ◽  
pp. 655-669 ◽  
Author(s):  
D G Hankin ◽  
T H Butler ◽  
P W Wild ◽  
Q -L Xue

Commercial capture of female Dungeness crabs, Cancer magister, is prohibited and minimum size limits for commercial harvest of male crabs are designed to allow most males to mate at least once before capture. Annual exploitation rates often exceed 90%, however, and the resulting scarcity of large males might reduce mating success among large females. We present new data regarding (i) sizes of male and female crabs collected in premating embraces, (ii) carapace width frequencies of female Dungeness crabs, (iii) presence of sperm plugs and sperm, and (iv) fecundity. Minimum carapace width of hard-shelled mating males typically exceeds postmolt carapace width of soft-shelled females (i), but female Dungeness crabs exceeding the minimum legal size of males usually account for less than 5% of mature adult female crabs (ii), and sublegal-sized males actively participate in mating (i). Remnants of sperm plugs, definitive indicators of mating, were found in 97.5% of recently molted large females (iii), suggesting that virtually all molting females mate regardless of size. On the basis of (ii) and (iv), hypothetical worst-case calculations, assuming that no large females could find mates, suggest that total egg production would be reduced by no more than 2-25% among molting female crabs.


Sign in / Sign up

Export Citation Format

Share Document