Isolation and characterization of microsatellite loci in the Amami rabbit (Pentalagus furnessi)

We report on the isolation and characterization of eight polymorphic and five monomorphic microsatellites in the Amami rabbit (Pentalagus furnessi). Microsatellite polymorphism was determined using 25 individuals. There were 2–11 alleles for each polymorphic locus with heterozygosity ranging between 0.08 and 0.76. Linkage disequilibrium was not suggested between any pairs among the eight polymorphic loci. We suggest that these primers be used in future studies to monitor population size, determine dispersal patterns, and genetic diversity within and between populations of this and related species.     

A new stomach worm,Obeliscoides pentalagi n. sp. (Nematoda; Trichostrongyloidea) of Ryukyu rabbits,Pentalagus furnessi (Stone, 1900)

Summary A new trichostrongylid nematode, Obeliscoides pentalagi n. sp., from the stomach of the Ryukyu Rabbit, Pentalagus furnessi, collected on Amami-ohshima Island, south Japan is described. O. pentalagi n. sp. resembles O. leporis Schulz, 1931 and O. travassosi Liu & Wu, 1941, but differs in the relative size and morphology of the dorsal ray and genital cone of the males. The number and distribution of longitudinal cuticular ridges of O. pentalagi n. sp. is similar to those of O. cuniculi multistriatus Measures & Anderson, 1983, but it differs in the morphology of the spicules, dorsal ray and genital cone in males, and in the morphology of the prevulval lobe of the females. The discovery of O. pentalagi further supports the hypothesis of a Eurasian origin of the genus Obeliscoides (Graybill, 1923) Graybill, 1924 (Durette-Desset, 1983; Durette-Desset & Chabaud, 1977; Measures & Anderson, 1983a, b, c, 1984). The number and distribution of longitudinal cuticular ridges and variation of the prevulval lobe in females of O. leporis Schulz, 1931 are also examined and compared with those of other species.     

使用粪堆数量估计日本奄美群岛上琉球兔的种群数量

为了测量奄美岛上濒危物种琉球兔 (Pentalagusfurnessi)的丰盛度 ,我们计数了森林中道路、溪流和森林地被物中的粪堆数量。计算用的模型包括新粪堆的数量及其年龄、总粪堆数量、每天产生的平均粪堆数 ,以及在森林地被物和溪边的粪堆数量的回归方程。估计在 1 993- 1 994年期间该岛上有 2 5 0 0 - 6 1 0 0只琉球兔 ,在 2 0 0 2 - 2 0 0 3年间有 2 0 0 0 - 4 80 0只。通过比较粪便丰盛度和在森林道路旁观察到的琉球兔数量 ,我们考察了该模型的有效性 ,最后将以前调查的数据应用于该模型以确定种群下降的程度     

Molecular phylogeny of Japanese Leporidae,the Amami rabbit Pentalagus furnessi,the Japanese hare Lepus brachyurus,and the mountain hare Lepus timidus,inferred from mitochondrial DNA sequences

We determined mitochondrial 12S ribosomal RNA (rRNA) and cytochrome b (cyt b) gene sequences in three leporid species of Japan, the Amami rabbit Pentalagus furnessi from the Ryukyu Islands, the Japanese hare Lepus brachyurus from Honshu, and a Japanese form of the mountain hare Lepus timidus ainu from Hokkaido. We compared the sequences with those of other taxa of leporids available in databases. Phylogenetic trees of the 12S rRNA gene sequences indicated that the lineage of P. furnessi diversified during the generic radiation of the leporids at an ancient time, which was estimated to have been the middle Miocene. Cyt-b gene trees revealed that the lineage of L. brachyurus branched off at an early stage in the speciation of Lepus, probably at the beginning of the Pliocene. The cyt b sequences of L. t. ainu were somewhat distinct from those of continental conspecific populations; this lineage divergence is likely to have occurred during the middle or late Pleistocene. The results show that the three regions of the Japanese archipelago, Ryukyu, Honshu-Shikoku-Kyushu, and Hokkaido, now preserve their own leporid taxa, each with a different extent of genetic endemicity. It is possible that the zoogeographic traits of the Japanese leporids are a consequence of the evolutionary dynamics of leporids in East Asia, in that the radiation centers of leporids are likely to have shifted from tropical, through temperate, to arctic zones.     

Breeding and rearing squirrel monkeys (Saimiri sciureus) in captivity.

A breeding colony of squirrel monkeys (Saimiri sciureus) was established to provide animals for behavioral research concerned with early development. The origin of the initial breeders was Peru, Colombia, and Bolivia. During the past 10 years, the colony has grown to 125 adult females, 20 adult males, and 120 immature animals of various ages. The annual conception rate for the last 5 years averaged 68%. This resulted in 84% viable births of which 82% survived past 6 months of age. The majority of the births (65%) occurred during June-August, and 87% during May-September. The most efficient and successful breeding strategy was to form mixed-sexed groups of 10--15 females and 2--3 males before the mating season began and to maintain the integrity of these groups with minimal interference. Progeny were reared apart from their natural mother without difficulty, and their growth and development were found to be similar to those of mother-reared monkeys.     

Laboratory rearing of lesser appleworm (Lepidoptera: Tortricidae)

The lesser appleworm, Cydia prunivora (Walsh), was reared successfully in the laboratory. Larvae of various instars were collected in the field from hawthorn fruit, Crataegus spp. Initially, immature apples served as the food source for the larvae in the laboratory. Rearing was conducted in a greenhouse and later in combination with a controlled environment room at 25 degrees C, 50-60% RH, and a photoperiod of 18:6 (L:D) h. Under these conditions, a generation required approximately 30 d. Fifty-six adult lesser appleworm moths emerged from the original field collected hawthorn fruits. After a decline in the number of the F1 generation to 39 moths, the colony on mature apples, increased to in excess of 10,000 moths by the fifth generation with a mean survival rate to adult of 68.0%. When production on immature apples was compared with that on four artificial diets, the most promising of the artificial diets was the lima bean-based diet currently used to rear the oriental fruit moth, Cydia molesta (Busck), with a mean survival rate of 46.4%. The other bean-based diets tested were not as satisfactory. Pear foliage was the preferred oviposition substrate of those tested, including apple and hawthorn foliage. No eggs were deposited on plain waxed paper or glass microscope slides; however, large numbers of eggs were deposited on waxed paper treated with a water extract of pear foliage and immature apples.     

Laboratory rearing method for the stem weevil,Hyperodes bonariensis (Coleoptera: Curculionidae)

The stem weevil, Hyperodes bonariensis Kuschel, was reared from egg to adult for eight generations on an artificial medium. At 26±0.5°C, 55±5% RH, and 12‐h photo‐period, development time from newly hatched larva to adult averaged about 28 days. There were four larval instars lasting about 14 days, followed by prepupal and pupal stages lasting a further 14 days. Oviposition occurred 2 weeks after adult emergence; mated females laid viable eggs. Ovarian diapause in some females was also noted. It is possible to rear about six generations a year under these conditions.     

Alternative diets for maintaining and rearing cephalopods in captivity

The requirement of live marine prey for cephalopod mariculture has restricted its practicality for inland research laboratories, commercial enterprises and home aquarists. We evaluated acceptability and resultant growth on: (a) frozen marine shrimps, (b) live and frozen marine polychaete worms, (c) live and frozen marine crabs, (d) frozen marine fishes, (e) live adult brine shrimp, (f) live freshwater fish and (g) live freshwater crayfish. The diets were presented for periods of 2 to 11 weeks to octopuses, cuttlefishes or squids and in most trials the results were compared to animals fed control diets of live marine shrimps, crabs or fish. Overall, frozen marine shrimp proved to be the best alternative diet tested. Adult Octopus maya on frozen marine shrimp diets grew as well as those on control diets at 2.8% body weight per day (%/d) compared to 2.0%/d on live freshwater crayfish, 1.4%/d on live marine polychaete worms and 0.8%/d on live freshwater fish (Tilapia sp.). Juvenile Octopus maya and Octopus bimaculoides also grew comparably to controls when fed frozen marine shrimps; growth rates ranged from near 3.0%/d at 3 months of age to nearly 2.5%/d at 6 months of age. Thus, these alternatives are acceptable as the octopuses end their exponential growth phase at an age of 3 - 5 months. Attempts to rear O. maya hatchlings and juveniles (up to 1 month of age) on dead foods resulted in high mortality and slow or negative growth. No live or dead alternative diet has been found yet that will promote good growth and survival in hatchling octopuses. Hatchling F3 generation Sepia officinalis (the European cuttlefish) were reared for 6 weeks exclusively on adult brine shrimp (Artemia salina).(ABSTRACT TRUNCATED AT 250 WORDS)     

Laboratory rearing of huhu,Prionoplus reticularis (Cerambycidae): insights into the gut microbiome

We developed a laboratory rearing method for huhu grubs, Prionoplus reticularis White (Coleoptera: Cerambycidae), on defined cellulose (cotton) and lignocellulose (pine) diets. Huhu grubs were shown to both gain weight and eventually undergo metamorphosis on these diets, two indications of successful use of the substrates for healthy growth. Since insects typically rely on their gut microbiome to assist in nutrient assimilation this rearing method was used to study the gut microbiome of P. reticularis, using the frass produced as a proxy for the gut contents. In this preliminary study patterns of fungal community diversity in frass suggest that their composition is significantly influenced by diet; however, the influence of diet on bacterial community diversity was less clear. Results do demonstrate the potential of the experimental model for studying shifts in the gut microbiome induced by diet change. This approach could prove essential in identifying microorganisms, or consortia, involved in the breakdown of lignocellulose.     

Laboratory rearing, biology and chemical control of the mushroom sciarid Lycoriella auripila (Diptera: Lycoriidae)

The mushroom sciarid was found to develop on a plant-derived diet of oat or soya meal. Details of simple rearing techniques and insecticidal assays of treated casing are given. In laboratory tests using ten chemicals, chlorfenvinphos and pirimiphosethyl showed persistent activity against larvae when used at 15 ppm and are suggested as suitable for incorporation in peat-chalk casing mixtures to give protection throughout cropping. The low figures obtained for phytotoxicity and residues in the crop suggest this technique would be acceptable in commerce. Diazinon remained active in casing for only a short time.     

Skeletal muscle fibre composition in new Zealand white rabbits, wild rabbits and wild rabbits bred in captivity: effect of heredity

1. The muscle composition of 3 breeds of rabbit was investigated histochemically in 3 muscle groups in order to identify whether heredity or environment was the predominant factor in dictating composition. 2. In the biceps femoris, differences between the breeds in myosin ATPase activity were due to heredity, whereas differences in oxidative potential were due to environment. 3. In the flexor digitorum longus, the wild rabbit possessed the highest percentage of type I fibres. This was environmentally induced.     

Laboratory rearing and life history of an emerging grape pest, Xylotrechus arvicola (Coleoptera: Cerambycidae)

Several aspects of the biology of Xylotrechus arvicola (Olivier), an emerging grape pest, were studied under laboratory conditions. Four diets were tested to rear this species in the laboratory. Among them, only one made rearing from larva to adult possible. The highest mortality, in all cases, was recorded during the first days of larval development. Larvae were kept 45 days at 8°C to break diapause in order to reduce the normal field larval developmental time. The species' developmental time was similar between sexes, while pupal developmental time and weight were significantly greater for females than for males. As part of a complementary study, life table parameters of females obtained from the larvae reared on the artificial diet were compared to those of females emerged from field-infested grape root wood. Both laid the majority of eggs in the first two weeks after emergence, and they had a similar pre-laying period. Nevertheless, the females from the diet-reared larvae lived significantly longer, laid eggs over a longer period of time and showed higher fertility than those emerging from infested grape root, suggesting that diet fulfils larval nutritional needs. The species' laboratory-reared population exhibited a low intrinsic growth rate value (rm=0.01) as a result of its long egg-to-adult developmental time and its high larval mortality.     

Laboratory rearing of Hydrochus japonicus (Coleoptera: Hydrochidae) suggests larvae live at the water bottom

The aquatic larvae of the family Hydrochidae (Coleoptera) have been considered ‘mystery larvae’, because ecological knowledge about them is lacking. We discovered that Hydrochidae larvae (Hydrochus japonicus Sharp) are benthic via laboratory rearing. The larvae have a terminal spiracular atrium, but we did not observe them breathing at the water surface. The larvae fed on Naididae worms that were collected from the same habitat.     

Reproduction of pike-perch (Stizostedion lucioperca) in captivity

A natural controlled spawning of pike-perch is suggested as the prevailing method providing good results in terms of embryo survival and fry production. Techniques of hormonal induction combined with water temperature manipulation are progressively developed. The eggs are most commonly incubated with the 'nest', or in Zug jars in the case of artificial fertilization. The larvae are then transferred into specific containers for their yolk absorption. The success rate from egg to free-swimming fry is 60–70%.     

Maintenance and breeding of Thrichomys (Trouessart, 1880) (Rodentia: Echimyidae) in captivity

South American histricognath rodents Thrichomys apereoides laurentius and Thrichomys pachyurus are natural hosts of Trypanosoma cruzi, agent of Chagas disease. We established breeding colonies of these species to serve as experimental models in various parasitological studies. Both species of Thrichomys have all the requirements necessary to become excellent laboratory models: they can be easily maintained in the standard laboratory conditions and breed throughout the year and they do not have any special dietary demands and can be fed by standard food pellets designed for laboratory mice. Both species produce precocious offspring that have their eyes and ears open, teeth erupted, fur well developed, and can eat solid food in the first week of life. T. a. laurentius has larger litter sizes and lower body masses at birth and weaning than T. pachyurus. Moreover, females of T. a. laurentius reach puberty earlier and with lower body mass than T. pachyurus.     

Reproduction of the mongoose lemur (Lemur mongoz) in captivity

Responses to questionnaires sent to 20 institutions holding Lemur mongoz did not reveal which aspects of management or husbandry could account for reproductive failure in the captive population, but allowed some qualitative comparisons with data compiled for captive and wild animals. In general, reproduction has occurred initially among wild-caught specimens before tapering off, and rarely occurs in the captive F₁ generation. Data compiled by the International Species Inventory System and the International Zoo Yearbook revealed an aging captive population with no recent reproduction. No aspect of group composition, activity patterns, seasonal light regime, reproductive cycles, or diet could be linked to the lack of reproduction; and among lemurs subjected to the same conditions, some were known to reproduce while others did not. Lack of knowledge about this species and the threat of extinction for both captive and wild populations make an investigation of reproductive biology imperative. Recommendations for a research program are given.