ABSTRACT
The importance of the protein ingestion during the adult stage on the mating success of males of Ceratitis capitata Wiedemann was evaluated in experiments of laboratory and field cage. In laboratory, the effects of protein ingestion during the first four or 12 days of the male adult life was assessed by the following parameters: mating success (capacity of being chosen by the female) and the number of males that give out pheromonal signals. Some experiments of mating success had been carried through with males in different ratios. In these tests, the number of males which had ingested protein (an unique male) was remained constant and the number of males fed without protein was gradually increased from 1:1 to 1:5. In the field cages, the mating success experiments were done using a 1:1 ratio. The results showed that the protein ingestion in the first four days of life did not influence any of the analyzed parameters. When the period of ingestion of protein was extended to 12 days, protein-fed males fed produced more pheromonal signals and had a higher mating success when at a 1:1 ratio in laboratory and field cage assays. In laboratory, females randomly chose males in any other tested ratio (1:2, 1:3, 1:4 and 1:5), indicating that the female may lose the perception to identify the male who ingested protein in the first 12 days.
Subject(s)
Ceratitis capitata , Dietary Proteins , Sexual Behavior, Animal/physiology , Animals , MaleABSTRACT
The importance of the protein ingestion during the adult stage on the mating success of males of Ceratitis capitata Wiedemann was evaluated in experiments of laboratory and field cage. In laboratory, the effects of protein ingestion during the first four or 12 days of the male adult life was assessed by the following parameters: mating success (capacity of being chosen by the female) and the number of males that give out pheromonal signals. Some experiments of mating success had been carried through with males in different ratios. In these tests, the number of males which had ingested protein (an unique male) was remained constant and the number of males fed without protein was gradually increased from 1:1 to 1:5. In the field cages, the mating success experiments were done using a 1:1 ratio. The results showed that the protein ingestion in the first four days of life did not influence any of the analyzed parameters. When the period of ingestion of protein was extended to 12 days, protein-fed males fed produced more pheromonal signals and had a higher mating success when at a 1:1 ratio in laboratory and field cage assays. In laboratory, females randomly chose males in any other tested ratio (1:2, 1:3, 1:4 and 1:5), indicating that the female may lose the perception to identify the male who ingested protein in the first 12 days.
Subject(s)
Animals , Male , Ceratitis capitata , Dietary Proteins , Sexual Behavior, Animal/physiologyABSTRACT
The objective of this study was to evaluate the effect of male ageing on male pheromone release and mating success of Ceratitis capitata (Wiedemann). The effects of male ageing on mating were evaluated on five and 21 d-old males by assessing their mating success (males chosen by a female for copulation) and the amount of males releasing the sex pheromone. The mating success was evaluated by using several ratios of young to older males by increasing the number of older males:young males from 1:1 to 5:1. The mating success of the 1:1 ratio was also evaluated in field cages. The evaluation of the mating success (in the 1:1 ratio) showed a clear preference of the females for young males. Sex pheromone emission was much more common on young than older males. Even in cases were older males were more abundant (ratios 2:1 and 3:1), females still chose the young males. However, females could not distinguish young from older males in ratios of 4:1 or 5:1. Our data indicate that the ageing of C. capitata males has a considerable negative effect on their reproductive success, especially if they are found in a proportion any lower than 3:1.
Subject(s)
Aging , Ceratitis capitata/physiology , Mating Preference, Animal , Animals , MaleABSTRACT
O objetivo deste estudo foi avaliar o efeito da senescência no sucesso de cópula e na secreção de feromônio sexual por machos de Ceratitis capitata (Wiedemann). O efeito do envelhecimento do macho sobre o acasalamento foi analisado utilizando-se machos com cinco e 21 dias de idade, através do seu sucesso de copula (escolha dos machos pela fêmea para cópula) e pela quantidade de machos que emitiram feromônio sexual. O sucesso de cópula foi avaliado através de várias proporções de machos jovens em relação a machos velhos pelo aumento do número de machos velhos:machos jovens de 1:1 até 5:1. O sucesso de cópula na proporção de 1:1 também foi avaliado em gaiola de campo. A avaliação do sucesso de cópula (na proporção 1:1) demonstrou clara preferência das fêmeas pelos machos jovens. A emissão de feromônio sexual foi mais comum em machos jovens do que em machos velhos. Mesmo em casos onde os machos velhos foram mais abundantes (proporções 2:1 e 3:1), as fêmeas continuaram escolhendo os machos jovens. Entretanto, as fêmeas não distinguiram mais os machos jovens em relação aos machos velhos nas proporções 4:1 ou 5:1. Os resultados indicam que o envelhecimento dos machos de C. capitata tem considerável efeito negativo sobre seu sucesso reprodutivo, especialmente se eles são encontrados em proporção menor do que 3:1.
The objective of this study was to evaluate the effect of male ageing on male pheromone release and mating success of Ceratitis capitata (Wiedemann). The effects of male ageing on mating were evaluated on five and 21 d-old males by assessing their mating success (males chosen by a female for copulation) and the amount of males releasing the sex pheromone. The mating success was evaluated by using several ratios of young to older males by increasing the number of older males:young males from 1:1 to 5:1. The mating success of the 1:1 ratio was also evaluated in field cages. The evaluation of the mating success (in the 1:1 ratio) showed a clear preference of the females for young males. Sex pheromone emission was much more common on young than older males. Even in cases were older males were more abundant (ratios 2:1 and 3:1), females still chose the young males. However, females could not distinguish young from older males in ratios of 4:1 or 5:1. Our data indicate that the ageing of C. capitata males has a considerable negative effect on their reproductive success, especially if they are found in a proportion any lower than 3:1.
Subject(s)
Animals , Male , Aging , Ceratitis capitata/physiology , Mating Preference, AnimalABSTRACT
The effects of protein intake on two adult male and female populations of Ceratitis capitata Wiedemann were assessed. One population consisted of flies reared for twenty years in the laboratory (Lab-pop); the other population consisted both of flies reared in the laboratory for approximately fifteen years and of the periodically introduced wild flies (Hybrid-pop). Three diets were tested: a no-yeast diet and two diets containing yeast (protein source) at the concentrations 6.5 g or 1.5 g per 100 ml diet. The parameters analyzed were: adult longevity, diet intake with and without yeast, and discrimination threshold for yeast. Protein intake increased Lab-pop adult longevity and did not affect longevity of the Hybrid-pop. Longevity in each population was similar for males and females fed on the same diet. Food behavior were similar for male and female adults of both populations; all preferred diets containing protein (yeast). Males and females in both populations ingested similar amounts of each diet. The discrimination threshold for yeast was similar for all males (0.5 g yeast/100 ml diet); Lab-pop females were able to detect the presence of smaller quantities of yeast in their diet, thus having a higher discrimination capacity (0.4 g/100 ml diet) as compared to the Hybrid-pop females (0.6 g/ 100 ml diet).
Neste estudo avaliou-se a influência da ingestão de proteína durante a fase adulta em machos e fêmeas de duas populações de Ceratitis capitata Wiedemann, uma composta por moscas criadas há vinte anos em laboratório sem a introdução de moscas selvagens (Lab-pop) e outra mantida há aproximadamente quinze anos com a introdução periódica destas (Hybrid-pop). Foram testadas três dietas: duas contendo levedura de cerveja (fonte protéica), respectivamente, nas concentrações de 6,5 g e 1,5 g por 100 ml de dieta e uma dieta sem levedura. Foram avaliados os parâmetros: longevidade dos adultos, ingestão de dietas com e sem levedura e limiar de discriminação para a levedura. A ingestão de proteína aumentou a longevidade dos adultos da Lab-pop, porém não influenciou a longevidade dos da Hybrid-pop. Dentro de cada população, ambos os sexos apresentaram longevidade similar, quando alimentados com o mesmo tipo de dieta. Adultos de ambas as populações apresentaram comportamento alimentar similar e preferiram se alimentar de dietas contendo fonte protéica (levedura) em relação a dietas sem essa fonte. Machos e fêmeas, em ambas as populações, ingeriram quantidades similares de uma mesma dieta. O limiar de discriminação para a levedura foi semelhante para os machos das duas populações (0,5 g/100 ml de dieta); as fêmeas da Lab-pop foram capazes de perceber uma quantidade menor de levedura na dieta, ou seja tiveram maior capacidade de discriminação (0,4 g/100 ml de dieta) em relação as fêmeas oriundas da Hybrid-pop (0,6 g/100 ml de dieta).
Subject(s)
Animals , Female , Male , Ceratitis capitata/physiology , Dietary Proteins/administration & dosage , Feeding Behavior , LongevityABSTRACT
Studies on fruit fly longevity and fertility are important to understand their demographic aspects and to orient implantation of integrated management strategies. This study investigated the longevity of adult Anastrepha species A. fraterculus (Wiedemann), A. sororcula (Zucchi), A. zenildae (Zucchi) and A. obliqua (Macquart). The reproductive pattern was also assessed throughout the life of the species A. sororcula and A. obliqua and fertility at eighteen days of life of the four species. A. zenildae longevity was similar to A. sororcula, longer than A. fraterculus and followed by A. obliqua. No statistical difference between the sexes was observed, except for A. obliqua. The decrease in survival occurred fastest in A. obliqua followed by A. fraterculus and A. sororcula, which was similar to A. zenildae. The highest mean of eggs at 18 days of life was for A. obliqua, followed by A. fraterculus, A. zenildae and A. sororcula. The reproductive pattern over the lifespan differed among the species assessed. A. obliqua presented a longer reproductive period, with more than one oviposition peak and greater daily and total egg production. The differences observed in the survival patterns and egg production and oviposition in the Anastrepha species reflect strategies that may be associated with environmental stability and/or differential response capacity to unstable environments. Thus the existence of similar survival strategies can be suggested between A. obliqua and A. fraterculus and between A. sororcula and A. zenildae.
Estudos sobre longevidade e fecundidade de moscas-das-frutas são importantes para o entendimento de seus aspectos demográficos e para orientar a implantação de estratégias de manejo integrado. Neste trabalho estudou-se a longevidade de adultos de Anastrepha fraterculus (Wiedemann), A. sororcula (Zucchi), A. zenildae (Zucchi) e A. obliqua (Macquart). Avaliou-se, também, o padrão reprodutivo ao longo da vida das espécies A. sororcula e A. obliqua e a fecundidade, aos dezoito dias de vida, das quatro espécies. A longevidade de A. zenildae foi semelhante à de A. sororcula e maior que de A. fraterculus, seguida de A. obliqua. Não diferiu estatisticamente entre os sexos, exceto para A. obliqua. O decréscimo da sobrevivência ocorreu mais rapidamente em A. obliqua, seguida de A. fraterculus e de A. sororcula, que foi semelhante a A. zenildae. A maior média de óvulos aos 18 dias de vida foi de A. obliqua, seguida por A. fraterculus, A. zenildae e A. sororcula. O padrão reprodutivo ao longo da vida diferiu entre as espécies avaliadas. A. obliqua apresentou período reprodutivo mais longo, teve mais de um pico de oviposição e maior produção diária e total de ovos. As diferenças observadas nos padrões de sobrevivência e de produção e postura de ovos das espécies de Anastrepha refletem estratégias que podem estar associadas à estabilidade do ambiente e/ou à capacidade diferencial de resposta a ambientes instáveis. Assim, pode-se sugerir a existência de estratégias de sobrevivência semelhantes entre A. obliqua e A. fraterculus e entre A. sororcula e A. zenildae.