大螟人工饲养技术的初步研究

利用大豆粉、玉米粉、麦胚和鲜茭白等成分配制了大螟Sesamia inferens(Walker)的半合成人工饲料,利用该饲料配方,发展了大螟的长期、继代饲养技术,即初孵-2日龄幼虫在茭白上饲养,3日龄-化蛹在人工饲料上饲养。利用该方法连续饲养大螟3代,幼虫的发育历期、蛹重、幼虫存活率、化蛹率、羽化率、卵孵化率和单雌产卵量等生活史参数与在天然饲料茭白上饲养的大螟相比,二者没有任何显著差异。而且利用该方法饲养,成本低、省工省力,能显著减少病原菌的感染。这说明该饲养技术适于大螟种群的长期、继代饲养。     

Induced oogenesis of the European eel (Anguilla anguilla L.) in freshwater condition

European eel is a catadromous fish species, which means that after living in freshwater premature individuals adapt to sea water, and migrate to the Sargasso Sea for spawning. Although male eel can be sexually matured even in freshwater, to date, it was believed that female eel can be matured only in seawater. Here we show that the process of sexual maturation may be induced in freshwater by treating female eels with carp pituitary (GSI = 9.87 ± 1.55%). It is thus proposed that seawater condition is not an obligatory environment for stimulating gametogenesis and for artificial maturation of the European eel in neither gender.     

Cloning of European eel (Anguilla anguilla) FSH-beta subunit, and expression of FSH-beta and LH-beta in males and females after sex determination

The European eel (Anguilla anguilla) is a catadromic teleost species with a complex life cycle, both in sea and freshwater environments. The sex determination phase of gonadal development occurs in a freshwater environment. Polymorphism occurs in increasing rates with respect to gender. While males stop growing at approximately 150 g, females continue to grow to being much larger. In this study, we cloned the cDNA FSH-beta subunit of the European eel (A. anguilla), and measured the mRNA levels of FSH-beta and LH-beta in males and females after sex determination. The FSH-beta subunit cDNA consisted of 1068 bp, encoding a 127 amino acid peptide. A comparison between European and Japanese eels of the FSH-beta amino acid sequence showed 98% similarity.     

Factors influencing tadpole deposition site choice in a frog with male parental care: An experimental field study

Parents have evolved a variety of strategies to minimize risks to their offspring, including complex choices regarding suitable rearing sites, based on abiotic and biotic factors, which differentially affect offspring survival. Because availability and quality of these sites are variable, parents may have to choose between immediately available lower‐quality rearing sites or extended search time. In some frog species with larval transport, parents are known to select bodies of water that are free of predators, cannibalistic tadpoles, or intraspecific competitors for larval deposition and rearing sites. We tested whether abiotic factors and the presence of predators and conspecific tadpoles affect tadpole deposition behavior in a population of smooth guardian frog, Limnonectes palavanensis, on the island of Borneo. Females lay eggs on land and males guard them until they hatch; after hatching, tadpoles climb onto the male's back and are subsequently transported to small pools of water on the forest floor, which are scarce and patchily distributed. We estimated the abundance of natural tadpole rearing sites in our study area and conducted experiments using artificial pools to test whether abiotic characteristics of these pools affect the probability of larval deposition. We also performed choice experiments to test whether males of L. palavanensis avoid pools with conspecific tadpoles or predators. Lastly, we tested whether the tadpoles of this species exhibit cannibalism. The abundance of natural deposition sites was low, and males readily used artificial pools for tadpole deposition. Males were less likely to deposit tadpoles in artificial pools located in steep areas, and males did not avoid depositing tadpoles in pools with conspecifics or with experimentally introduced predators. Males exhibited clutch‐partitioning behavior, dividing tadpoles between adjacent artificial pools. Pool availability, rather than the presence of potential competitors or predators in a pool, affects tadpole deposition decisions in this species.     

Development,survival, body weight,longevity, and reproductive potential of Oemena hirta (Coleoptera: Cerambycidae) under different rearing conditions

Oemona hirta (F.) is a New Zealand native longicorn beetle, whose larvae bore into the wood of branches and stems of living trees and vines, causing serious damage. To explore effective methods for maintaining laboratory colonies and biology of immature stages of this species we evaluated four laboratory rearing methods with both natural and artificial diets and compared biological parameters of laboratory colonies with those of field-collected insects. On an artificial diet, approximately 40% of neonate and 70% of autumn- and 11% of winter-collected larvae reached adulthood. Neonate larvae could not complete their development in cut poplar (Populus nigra variety italica Koehne) twigs; however, when twigs were standing in water >46% of neonate larvae survived to adulthood. Mean larval development time ranged from approximately150 to almost 300 d, depending on rearing methods. Mean pupal stage ranged from 15 to 19 d. Adult females were significantly heavier than males. Although adult females from field-collected twigs and reared on the artificial diet had similar mean body weight, which was significantly greater than that of other rearing colonies, the potential fecundity was the highest in the former (83.1 +/- 29.4 eggs) and the lowest in the latter (33.5 +/- 9.1 eggs). In all laboratory-reared and field-collected insects, the total number of eggs produced (eggs laid + eggs that remained in dead female body) by females was positively correlated with their body weight. When larvae fed on the artificial diet, there was no positive correlation between the number of eggs successfully laid and female body weight. However, when larvae lived on natural food, a positive correlation was found. In laboratory colonies, mean longevity of females (36 to 52 d) was slightly greater than that of males (30 to 50 d) without significant difference between sexes but in the adults from field-collected twigs, males (52 d) lived significantly longer than females (33 d). In terms of time, labor, and the number of resulting adults, collecting larvae in the field in autumn and then transferring them onto artificial diet is the most effective method for maintaining a laboratory colony.     

Colonization of a hybrid strain to restore male Anastrepha ludens (Diptera: Tephritidae) mating competitiveness for sterile insect technique programs

To restore male mating competitiveness of Mexican fruit flies, Anastrepha ludens (Loew) (Diptera: Tephritidae), reared for sterile insect releases by the Mexican Fruit fly Eradication Campaign, two strain replacement techniques were evaluated. Field cage male competitiveness tests revealed that laboratory males of the Metapa strain mated 3 times less often with wild females than field-collected wild males. A strain developed from the cross of wild males and laboratory females (hybrid strain) was similar to a strain developed from the cross of laboratory males and females (laboratory strain) in that its females produced similar amounts of eggs and the eggs displayed similar levels of hatch and egg-to-pupa transformation in artificial diet. By contrast, a strain developed from the cross of wild males and females (wild strain), forced into artificial rearing, experienced a series of bottlenecks involving reduced egg laying and extremely poor development in diet. The male F1 progeny of the hybrid strain and field-collected wild males outcompeted Fl laboratory males in field cage tests for matings with field-collected wild females. In conclusion, we found that strains developed from the cross of wild males and laboratory females allowed us to restore male mating competitiveness of F1 Mexican fruit flies without compromising mass-rearing production.     

Caste regulation in the pharaoh's ant Monomorium pharaonis: the influence of queens on the production of new sexual forms

ABSTRACT. In colonies of Monomorium pharaonis (L.), the presence of fertile queens normally prevents the production of new queens and males (sexuals). The inhibitory effect of the presence of fertile queens is not shared by virgin queens or by freshly killed dead queens, but can be substituted by the artificial introduction of eggs. Moreover, fertile queens made sterile by exposure to a Juvenile Hormone analogue lose their ability to prevent the rearing of new sexuals. Thus, the inhibitory action of queens is mediated via the eggs that they lay, such that the rearing of new sexuals is limited to the times when either the number or fecundity of extant queens is reduced. Workers appear able to detect changes in the number of eggs present in the colony. When eggs are plentiful (i.e. when queens are laying at maximum rates), only worker brood is reared, but if egg numbers decline, workers will respond by rearing a new batch of males and queens. This method of caste regulation is highly efficient, and the inhibitory action of eggs on the production of sexuals is comparable to the action of 'queen substances' reported in some other social insects.     

埋植17α—甲基睾酮诱导点带石班鱼性转化技术

论述了埋植17α-思虑在睾酮诱导点带石斑鱼（Epinephelus malabaricus)性转化的方法,包括药物的处理,用量,手术操作等3龄的雌性点带石班鱼经过2次埋植外源激素手术转化为功能性雄鱼,139d后58％可挤出精液,301d后100％可挤出精液,功能性雄鱼用于人工繁殖,亲鱼自然产卵,1999－2000年2年内共孵出存鱼7103万尾,所得仔鱼用鱼苗培育,得到发育正常的幼鱼,认为埋植外源激素诱导点带石斑鱼完成性转化的方法简便可行,能满足规模化人工繁殖的需要。     

Rearing management of rabbit males selected by high growth rate: the effect of diet and season on semen characteristics

A total of sixty-six young males were used to evaluate the effect of low (L), medium (M) and high (H) concentrations of dietary digestible energy received during the rearing seasons (autumn and spring) on the performance and main semen characteristics of males for artificial insemination selected by a high growth rate. Males reared during the spring season presented a significantly higher weight at weaning than those reared during the autumn season (P < 0.001), and these differences were maintained until the end of the trial. The requirements of the males were easily covered as a general rule. In the autumn group, the males were unable to intake the digestible protein recommended only during their 3rd month of life, especially with low concentrate diets (P < 0.05). H males showed higher semen concentration and production during the autumn season, while L males showed a higher semen concentration and production than M males during the spring season, the H group showed intermediate values (P < 0.001). Males reared during the spring season showed significantly higher values of sperm concentration (P < 0.01) and production (P < 0.01). H males presented a lower percentage of spermatozoa with cytoplasmic droplets than the L group (P < 0.05) and the lowest values for sperm abnormalities during the autumn season, while the L group presented higher values for percentage abnormalities, especially during the last month controlled (P < 0.05). As a general rule, the main motility parameters controlled were not affected by the rearing diet received nor the season. These results seem to indicate that the management of rabbit males during the growing and rearing periods seem to significantly affect their subsequent performance and semen production.     

Deceptive female oviposition behaviour elicits male ejaculation in the European bitterling

In European bitterling Rhodeus amarus , fish that lay their eggs in the gill chambers of living freshwater mussels, females perform conspicuous behaviours associated with spawning that increases the probability of males performing ejaculatory behaviour and participating in a spawning. A significant positive association was detected between behaviour in which a female performs a spawning action but without releasing eggs, here termed 'deceptive female oviposition', and ejaculatory behaviour by courting males.     

埋植17α-甲基睾酮诱导点带石斑鱼性转化技术

论述了埋植17α-甲基睾酮诱导点带石斑鱼(Epinephelus malabaricus)性转化的方法,包括药物的处理、用量、手术操作等．3龄的雌性点带石斑鱼经过2次埋植外源激素手术转化为功能性雄鱼,139d后58％可挤出精液,301d后100％可挤出精液．功能性雄鱼用于人工繁殖,亲鱼自然产卵。1999～2000年2年内共孵出仔鱼7103万尾．所得仔鱼用于鱼苗培育,得到发育正常的幼鱼．认为埋植外源激素诱导点带石斑鱼完成性转化的方法简便可行,能满足规模化人工繁殖的需要．     

A snail with unbiased population sex ratios but highly biased brood sex ratios

Extraordinary sex ratio patterns and the underlying sex-determining mechanisms in various organisms are worth investigating, particularly because they shed light on adaptive sex-ratio adjustment. Here, we report an extremely large variation in the brood sex ratio in the freshwater snail, Pomacea canaliculata. In eight rearing series originating from three wild populations, sex ratios were highly variable among broods, ranging continuously from almost exclusively males to almost exclusively females. However, sex ratios were similar between broods from the same mating pair, indicating that sex ratio is a family trait. Irrespective of the large variations, the average sex ratios in all rearing series were not significantly different from 0.5. We argue that Fisher's adaptive sex-ratio theory can explain the equal average sex ratios, and the results, in turn, directly support Fisher's theory. Polyfactorial sex determination (in which sex is determined by three or more genetic factors) is suggested as the most likely mechanism producing the variable brood sex ratio.     

同翅目昆虫人工饲料饲养技术

本文从人工饲料的组成与类型、饲养方法及饲养结果等方面总结了同翅目昆虫人工饲料饲养技术的研究现状 ,并简要讨论了其存在的问题和改进方法。     

Investigations on inducing sexual maturity in the male eel Anguilla anguilla L.

Studies on inducing sexual maturity in European eel males have been made. The fish were kept in fresh or artificial sea water at a temperature of 20°C, and hormonal injections were given. Among the hormones used, the positive results were obtained with human chorionic gonadotropin. All the male eel injected with this hormone produced sperm containing living spermatozoa. The quality of sperm of the males kept in fresh water was poorer in comparison with the sperm of the males kept in the artificial sea water.     

Two Meridic Diets for Perillus bioculatus (Heteroptera: Pentatomidae), a Predator of Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

Two artificial diets, devoid of insect components, were developed for the predator Perillus bioculatus (Fabricius). The diets based on chicken liver and tuna fish were designed to approach the nutritional characteristics of the primary insect prey, Leptinotarsa decemlineata (Say) eggs. P. bioculatus was reared on diet 2 for 11 consecutive generations without cumulative detrimental effects on its biology. Developmental time and preovipositional period were significantly longer, and egg viability, survival from egg to adult, and fecundity were significantly lower in P. bioculatus individuals reared on artificial diets than in those reared on L. decemlineata eggs. A significant reduction in developmental time, increase in survival from egg to adult, and reduction in length of the preovipositional period were observed after 11 generations of in vitro reared P. bioculatus on diet 2. These changes may indicate that the predators experience some degree of adaptation to the diet after several consecutive generations of in vitro rearing. No changes in egg viability were observed after 11 generations of in vitro rearing. Adult female weight was unaffected when reared on artificial diet, but a significant increase was observed after 11 generations of in vitro rearing. Females under all treatments weighed an average of 11.6 mg more than the males.     

Substrate influences mating success and transmission of courtship vibrations for the parasitoid Cotesia marginiventris

The influences of artificial and natural rearing substrates on mating success were investigated for the parasitoid wasp Cotesia marginiventris (Cresson) (Hymenoptera: Braconidae), a candidate for augmentative biological control of various lepidopteran pests. Five rearing substrates were tested: plastic, glass, chiffon fabric, and leaves of two host plants, bean [Vigna unguiculata (L.) (Fabaceae)] and maize [Zea mays L. (Poaceae)]. Mating success was highest on chiffon, lowest on plastic and glass, and intermediate on maize and bean. The transmission characteristics of one component (buzz 1) of the courtship vibrations produced by male wing fanning were investigated using laser vibrometry. The duration of buzz 1 was longer on maize, bean, and chiffon than on plastic and glass. The fundamental frequency of buzz 1 (~300 Hz) was lowest on bean and highest on glass, and intermediate among other substrates. The relative amplitude of buzz 1 was higher on chiffon than on plastic, glass, or bean, and intermediate on maize. The relative importance of airborne sound and substrate vibration as courtship signals was also investigated with experiments that manipulated the production of courtship vibrations and the mating substrates. The amplitude of courtship vibrations on chiffon was significantly higher for winged males than for dealated males. The mating success of males was impacted by both the presence of wings and the mating substrate. These findings suggest that mating success and transmission of courtship vibrations are influenced by the rearing substrate, and that courtship vibrations are critical to mating success in C. marginiventris. Future efforts to mass rear this parasitoid and other insects should consider the potential influences of rearing substrates on mating.     

Growth and development of the Angoumois grain moth, Sitotroga cerealella in an artificial diet

A simple method for rearing the Angoumois grain moth, Sitotroga cerealella, in an artificial diet is described. Although the larvae normally feed within grain kernels, they readily became established in pellets containing a mixture of five natural products. An evaluation of the growth rate in this medium revealed a marked sex difference. The males attained a maximum mean larval weight of 7·2 mg at 22 days compared with 12·3 mg for mature females at 24 days. Both sexes were found to pass through four larval instars. A study of the pupation rate showed that males reached 50 per cent pupation a full 5 days before females. While both sexes spent about 6·7 days in the pupal-pharate adult stage, the mean weight of newly-ecdysed female adults was 77 per cent greater than that of the males.     

Effect of male inflorescence of Castanea mollissima on the reproductive development and lifetime of Bactrocera minax

Previous work reveals that newly emerged adult Chinese citrus flies, Bactrocera minax (Enderlein), emerges from the ground in the mosaic-type citrus orchard of the hilly terrain landform dispersed into adjacent forest, and the newly emerged adult flies fed on male inflorescence of the Chinese chestnut, Castanea mollissima Blume (Fagaceae). The potential impact of male inflorescence of C. mollissima on the longevity, and survival of adult females and males, the ovarian development of adult females, and the abdominal index, ovarian index, and egg length of the fourth ovarian grade of living females, as well as the flowering process of the male inflorescence of the Chinese chestnut, were studied with the three methods of rearing (normal rearing, hungry rearing, and bagging rearing). For all three rearing treatments, the longevity of all adults could live up to 38 days, there were similar time dynamics for the average survival of female and male adult flies. Of the total females, 32.1%–100% females with bagging rearing could attain the fourth ovarian grade like those in rearing and hunger rearing. The abdominal index, ovarian index, and egg length of the fourth ovarian grade of 27–39 days’ old living females with bagging rearing (it corresponds to the late flower withering period), were 75.1%, 49.8% and 89.6% of those with normal rearing, and 73.2%, 60.6% and 90.8% of those with hungry rearing, respectively. The male inflorescence of C. mollissima can satisfy the nutritional requirements of adult B. minax, enabling their survival and normal reproduction. This study can provide references for development and application of artificial feed and food attractants of adult B. minax.     

Contractile properties and myosin heavy chain composition of rat tongue retrusor musculature show changes in early adulthood after 19 days of artificial rearing.

Previously, we showed that artificial rearing using the "pup in a cup" model results in decreased tongue activity and caused some minor alterations in the tongue retrusor musculature. However, the artificial rearing time frame previously chosen was brief (11 days). The purpose of the present investigation was to extend the artificial rearing period from postnatal days 3 to 21 (P21) to determine whether significant alterations occur as a result of this reduced tongue use. Several changes in contractile properties due to the artificial rearing process were observed, which fully recovered by postnatal days 41 to 42 (P41-2). These changes included a shorter twitch contraction time, shorter twitch half-relaxation time, and decreased fatigue resistance. Styloglossus muscle exhibited more neonatal myosin heavy chain (MHC) isoform at P21 for the artificially reared (AR) group. Changes that were persistent at P41-2 were also observed. Maximum tetanic tension was lower for the AR group at P21 and P41-2 compared with their dam-reared counterparts. Twitch tension was also lower by P41-2 in the AR group. At P41-2, the AR group exhibited an increase in MHC IIa and a decrease in MHC IIb for the styloglossus muscle. In addition, the AR group exhibited a decreased MHC IIb for the long head of the biceps brachii at P41-2. Our results are similar to other models of hindlimb immobilization and suspension. By extending our artificial rearing period, this reduced tongue activity induced acute changes and alterations in the tongue retrusor musculature that persisted into early adulthood.     

真水狼蛛纺器的扫描电镜观察

通过室内饲养,获得了不同龄期的真水狼蛛。对其纺器扫描电镜观察表明：真水狼蛛的纺器表面分布许多纺管,纺管的数目随着龄期的增大面增加。１龄幼蛛纺器分化没有完成。因而不能纺丝。雌蛛和雄蛛在纺器的排列位置、形态、纺管类型和纺管数目上都存在较大差异。纺器的形态、结构与纺器纺丝、结网的功能相适宜。