Laboratory environment effects on the reproduction and mortality of adult screwworm (Diptera: Calliphoridae)

Abstract

o objetivo de fornecer insetos para programas para sua erradicação, através da técnica do inseto estéril. Novos métodos de criação têm auxiliado na redução dos custos desses programas de erradicação. Nós examinamos o efeito e a interação de três temperaturas (24,5, 29,5 e 34,5 o C), duas dietas (carboidrato e carboidrato + proteína) e três densidades populacionais (300, 400 e 500 moscas/gaiola), na fecundidade eclosão de larvas, número de ovos fertilizados, mortalidade (macho e fêmea) e desenvolvimento dos ovários. As três densidades populacionais não afetaram nenhum dos parâmetros avaliados. O uso da dieta protéica aumentou a produção de ovos em todas as temperaturas testadas. O tipo de dieta não afetou a eclosão de larvas e mortalidade de fêmeas. A mortalidade dos machos foi signifi cativamente maior quando alimentados com a dieta protéica e criados a 24,5o C e 34,5 o C. A eclosão de larvas foi signifi cativamente menor quando as moscas foram criadas a 34,5 o C. Nas temperaturas mais elevadas (37 o C e 40 o C), a produção de ovos, eclosão de larvas, fertilidade e mortalidade foram afetadas desfavoravelmente. Ainda nessas mesmas temperaturas, durante a oogênese, não houve a formação adequada do estoque de alimento para os embriões. O fotoperíodo curto (1L: 23E) propiciou maior produção de ovos, eclosão de larvas e fertilidade, e diminuiu a mortalidade quando comparado ao fotoperíodo padrão em criações (12L: 12E). PALAVRAS-CHAVE: Temperatura, produção de ovos, desenvolvimento do ovário ABSTRACT -The New World screwworm, Cochliomyia hominivorax Coquerel, is mass reared for screwworm eradication initiatives that use the sterile insect technique. New methods for rearing have helped to reduce the cost of the eradication program. We examined the effect and interaction of three temperatures (24.5, 29.5 and 34.5ºC), two diets (2% spray-dried blood plus 0.05% vitamins and corn syrup carrageenan) and three population densities (300, 400, and 500 fl ies/cage) on egg production, egg hatch, number of observable fertilized eggs, mortality (male and female) and ovarian development. The three population densities did not affect any of the parameters monitored. Using the protein diet increased egg production at all temperatures. Diet did not affect egg hatch or female mortality. Male mortality was signifi cantly greater when fed the protein diet and reared at 24.5ºC and 34.5ºC. Egg hatch was signifi cantly less when the fl ies were reared at 34.5ºC. When exposed to high temperatures (37ºC and 40ºC) egg production, egg hatch, fertility and mortality were adversely affected. At the higher temperatures, yolk did not adequately form during oogenesis. When compared to the normal rearing photoperiod (12 L: 12 D), short photoperiod (1 L: 23 D) increased egg production, egg hatch and fertility but lowered mortality.

The new world screwworm: prospective distribution and role of weather in eradication

“…1d) (Berkebile et al, 2006). More important, the mortality rate of eggs (failure to hatch) deposited by females held for 5 days at constant temperatures in the range 23-40 • C (28 dd) increases with temperature ( Fig.…”

Feasibility of Using a Caribbean Screwworm for SIT Campaigns in Brazil

“…In crosses ÔjÕ and Ôk,Õ 30 females were exposed to 1 fertile and 9 sterile males. After 7 d, females were allowed to oviposit on a plate containing ground meat and spent larval diet in a dark room (37ЊC; 80% relative humidity [RH]) for 2 h (Berkebile et al 2006). During the oviposition period, the plates with adult diet were covered to avoid feeding.…”

“…The Þrst set (parental crosses) compared intrastrain and reciprocal interstrain crosses (ÔaÕ to ÔdÕ) and the second set (F 1 crosses; ÔeÕ to ÔiÕ) compared four backcrosses to BRA and a BRA intrastrain cross (Table 3). For each cross, 80 couples were placed together for 7 d, after which the females were allowed to oviposit (Berkebile et al 2006). Eggs were separated according to Berkebile and Skoda (2002).…”

Raising of Horn Fly Haematobia irritans (L.) (Diptera: Muscidae) in Laboratory by Means of Egg and Larva Inoculation

“…Studies have shown the influence of temperature on ovarian development and egg laying [6] [7], as well as the interference of physical and nutritional properties of bovine feces on egg production [8] [9] and larval growth [10]- [12].…”

“…Commonly described methodologies for obtaining flies in laboratory are manual deposition of eggs onto fecal [9] [11], fresh [6] [19] and lyophilized mass [20]; egg laying by pregnant females directly onto the feces in laboratory [13]; egg storage in pieces of "organza" fabric [16] or filter paper [4] [5] [8] followed by deposition onto fecal plates.…”