The effects of ambient temperature on food selection, nutrient utilization, and performance in a generalist caterpillar, Spodoptera litura

Nergui Ravzanaadii,Kwang Pum Lee 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.05

Temperature and nutrition are the two most important environmental factors influencing growth and survival in immature insects. There is ample evidence of interactions between these two factors but still little is known how changes in thermal environment affect feeding and nutrient utilization insect ectotherms. The aim of this study is to investigate the potential effects of ambient temperature on food selection and post-ingestive nutritional physiology in a generalist-feeding caterpillar of Spodorptera litura. Two separate experiments were performed. The first was a food choice experiment in which caterpillars were maintained through their final larval stadium under one of three constant temperatures(20,25,30°) and given a choice between two nutritionally unbalanced diets that differed in protein(p) and carbohydrate(c) content (p42:c0 vs p7:c35 and p35:c7 vs p7:c35). In the second experiment, caterpillars were kept at the same thermal conditions as the first experiment but received a single diet from three no-choice feeding treatments(p35:c7,p21:c21and p7:c35). When raised at the highest temperature (30C), caterpillars from the choice experiment selected significantly more carbohydrate than those on lower temperatures whereas protein intake did not differ significantly between caterpillars across three test temperatures. Results from the no-choice experiment showed that lipid storage efficiency was reduced when caterpillars were maintained at the highest temperature(30C). In both experiments, growth rate increased progressively with rising temperature. However, there was a significant temperature-by-diet interaction, with growth rates increasing more rapidly on p21:c21 diet than on the other diets(p35:c7 and p7:c35). Our results demonstrate that caterpillars adjust their nutrient preference to meet the increased energetic demand at high ambient temperature.

Nutritional Value of Mealworm, Tenebrio molitor as Food Source

Ravzanaadii, Nergui,Kim, Seong-Hyun,Choi, Won-Ho,Hong, Seong-Jin,Kim, Nam-Jung Korean Society of Sericultural Science 2012 International Journal of Industrial Entomology Vol.25 No.1

Nutrition value of mealworm, Tenebrio molitor was analyzed due to increasing demand of usage as a protein source for domestic animals and even further for human consumption. The purpose of the present work was to determine the chemical compostion of the Tenebrio molitor larvae, adult that were maintained under standard condition for further usage of mass-rearing system and its exuvium, and excreta. Tenebrio molitor, larvae, adult, exuvium and excreta contained 46.44, 63.34, 32.87, and 18.51% protein respectively, suggested that even excreta could be used as an additional supplement in food recycling process. This protein was also rich in amino acids such as Isoleucine, leucine and Lysine which all met the nutritional value recommended by the Food and Agriculture Organization. Fatty acid composition was detected with high component of oleic acid (C18:1), along with linoleic acid (C18:2) and palmitic acid (C16) in all adult, larvae, exuvium and excreta. These oleic acid (C18:1), linoleic acid (C18:2) and palmitic acid (C16) components were the same or even highly contained in excreta of mealworm 22.29, 47.19 and 19.17% respectively. Longer chains of unsaturated fatty acids consisted of two to three double bonds are known as healthy product was recognized in large amount. These results show new ways to consume mealworms and its waste for animal and human consumption.

Nutritional Value of Mealworm, Tenebrio molitor as Food Source

( Nergui Ravzanaadii ),( Seong Hyun Kim ),( Won Ho Choi ),( Eong Jin Hong ),( Nam Jung Kim ) 한국잠사학회 2012 International Journal of Industrial Entomology Vol.25 No.1

Nutrition value of mealworm, Tenebrio molitor was analyzed due to increasing demand of usage as a protein source for domestic animals and even further for human consumption. The purpose of the present work was to determine the chemical compostion of the Tenebrio molitor larvae, adult that were maintained under standard condition for further usage of mass-rearing system and its exuvium, and excreta. Tenebrio molitor, larvae, adult, exuvium and excreta contained 46.44, 63.34, 32.87, and 18.51% protein respectively, suggested that even excreta could be used as an additional supplement in food recycling process. This protein was also rich in amino acids such as Isoleucine, leucine and Lysine which all met the nutritional value recommended by the Food and Agriculture Organization. Fatty acid composition was detected with high component of oleic acid (C18:1), along with linoleic acid (C18:2) and palmitic acid (C16) in all adult, larvae, exuvium and excreta. These oleic acid (C18:1), linoleic acid (C18:2) and palmitic acid (C16) components were the same or even highly contained in excreta of mealworm 22.29, 47.19 and 19.17% respectively. Longer chains of unsaturated fatty acids consisted of two to three double bonds are known as healthy product was recognized in large amount. These results show new ways to consume mealworms and its waste for animal and human consumption.

갈색거저리(Tenebrio molitor) 성충, 알의 생물학적 특성 구명

김남정,김성현,홍성진,이영보,박해철,최원호,Nergui Ravzanaadii 한국응용곤충학회 2012 한국응용곤충학회 학술대회논문집 Vol.2012 No.10

일반적으로 곤충의 영양성분은 단백질과 지방, 광물질 및 비타민을 풍부히 함유하고 있고, 아미노산 조성은 대부분의 케이스에서 곡물이나 콩류에 비해 우수하고 단쇄불포화지방산이 풍부하다. 이에 곤충을 이용한 사료는 매우 안전하고 저단가의 고품질 단백질 사료의 생산을 가능하게 할 수 있기에 사료용 곤충 갈색거저리 특성을 파악하고자 하였다. 갈색거저리는 성충이 된 후 빠르게는 5일 이후부터 산란하기 시작하여 성충 전기간동안 산란하는 특성이 있으나, 주로 성충 초기・중기 기간에 집중적으로 산란하는 것을 확인하였다. 수명 및 산란성을 조사한 결과, 수명(암컷/수컷) 152.4/150.7일, 산란전기간 7.8일, 산란기간 평균 114.1일, 산란수 364개이었다. 또한 성충은 먹이에 알을 붙여서 산란하는 특성이 있으며, 사육상자 내 곡물류, 채소류 등 함께 사용 시 밀기울이 가장 산란선호성이 높았으나, 각 재료를 단독으로 사용 시 밀기울, 옥수수분말이 선호도가 높았다. 알의 색깔은 유백색, 크기는 장경 1.93㎜, 단경 1.00㎜이었다. 알 보호온도별 부화율은 17.5~27.5℃일 경우 80%이상이었으나, 15℃이하에서는 거의 부화되지 않았다.

Temperature-Dependent Development of the Swallowtail Butterfly, Sericinus montela Gray

( Seong Jin Hong ),( Sun Young Kim ),( Nergui Ravzanaadii ),( Kyoungha Han ) 한국잠사학회 2014 International Journal of Industrial Entomology Vol.29 No.2

The aim of this study is to investigate the effects of ambient thermal environments on the development of swallowtail butterflies ( Sericinus montela Gray). Developmental durations and survival rates of S. montela were examined at two crucial developmental stages, embryonic and larval development, at varying temperatures ranging from 15℃ to 35℃. As expected, our results indicated that increasing temperatures decreased the developmental duration and survival rate of the eggs. However, the larvae and pupae showed maximum survival rates at 20.0℃ and 25.0℃, and the represented durations were similar to those of the eggs. Larval development was stage-specific, revealing that the fourth and fifth instars at the later stages were more susceptible to temperature variation. When considering both parameters, the optimal development of S. montela occurred within the temperature range of 20.0-25.0℃. The lower threshold for the complete development of S. montela from eggs to eclosion of adults was calculated at 10.6℃ by linear regression analysis. The estimated value is similar to that of other endemic insects distributed in temperate climate zones, which indicates that S. montela belongs to a small group of swallowtails adjusted to low ambient temperatures. From the results, we predict that the full development of S. montela could be achieved within the temperature range of 17.5-30.0℃. Embryonic development ceased at both test temperature extremes, and no further larval development proceeded after the third instar at 35.0℃. These results suggest that embryogenesis can be significantly influenced by slight variations in the ambient thermal environment that fall below the optimal range.

Temperature-Dependent Development of the Swallowtail Butterfly, Sericinus montela Gray

Hong, Seong-Jin,Kim, Sun Young,Ravzanaadii, Nergui,Han, Kyoungha,Kim, Seong-Hyun,Kim, Nam Jung Korean Society of Sericultural Science 2014 International Journal of Industrial Entomology Vol.29 No.2

The aim of this study is to investigate the effects of ambient thermal environments on the development of swallowtail butterflies (Sericinus montela Gray). Developmental durations and survival rates of S. montela were examined at two crucial developmental stages, embryonic and larval development, at varying temperatures ranging from $15^{\circ}C$ to $35^{\circ}C$. As expected, our results indicated that increasing temperatures decreased the developmental duration and survival rate of the eggs. However, the larvae and pupae showed maximum survival rates at $20.0^{\circ}C$ and $25.0^{\circ}C$, and the represented durations were similar to those of the eggs. Larval development was stage-specific, revealing that the fourth and fifth instars at the later stages were more susceptible to temperature variation. When considering both parameters, the optimal development of S. montela occurred within the temperature range of $20.0-25.0^{\circ}C$. The lower threshold for the complete development of S. montela from eggs to eclosion of adults was calculated at $10.6^{\circ}C$ by linear regression analysis. The estimated value is similar to that of other endemic insects distributed in temperate climate zones, which indicates that S. montela belongs to a small group of swallowtails adjusted to low ambient temperatures. From the results, we predict that the full development of S. montela could be achieved within the temperature range of $17.5-30.0^{\circ}C$. Embryonic development ceased at both test temperature extremes, and no further larval development proceeded after the third instar at $35.0^{\circ}C$. These results suggest that embryogenesis can be significantly influenced by slight variations in the ambient thermal environment that fall below the optimal range.