Kin recognition in white-footed deermice (Peromyscus leucopus)

The degree of relatedness between individuals can influence subsequent social behaviour. Peromyscus leucopus populations may consist, in part, of related individuals. Kin recognition could benefit individuals in establishing sub-populations and inbreeding avoidance. White-footed deermice were tested in pairs according to one of the following categories: littermate sibling, cagemate (1s-c), littermate sibling, non-cagemate (1s-nc), non-littermate sibling, non-cagemate (nls-nc), non-sibling, cagemate (ns-c), and non-sibling, non-cagemate (ns-nc). Differences between n1s-nc and ns-nc encounters indicate kin recognition that cannot be due to prior contact. Both sexes Investigated related strangers (nls-nc) of the opposite sex more than unrelated strangers (ns-nc). Males Avoided related stranger males and Chased unrelated stranger males. Females Warded unrelated strangers longest. This is the first study to demonstrate kin recognition that is not based on prior contact in a small rodent.     

Differential reactivity of wild and semi-domestic deermice (Peromyscus maniculatus)

A strain of deermice (Peromyscus maniculatus bairdii) maintained in captivity for 17 years (twenty to twenty-five generations) was compared with the laboratory-reared offspring of a field-caught population in regard to the propensity to enter an unfamiliar open-field. Controls were established for the post-natal maternal environment and post-weaning rearing experience (laboratory cages versus outdoor enclosure).The semi-domestic subjects exhibited significantly shorter latencies in entering the open-field and significantly fewer subjects failed to enter during the 2-min test trial. Fostering offspring both between and within strains did not affect these results.Whereas early experience in a semi-natural field enclosure did not change the open-field behaviour of the wild genotype subjects, propensity to enter was significantly decreased in the male semi-domestic animals.Only the laboratory reared semi-domestic subjects showed significantly decreased avoidance after 48 hr habituation to the open-field. The propensity of both strains to enter the open-field was significantly decreased in the presence of a caged least weasel.The reduced reactivity of the semi-domestic subjects was explained by differential selection pressure in field and laboratory environments.     

Illumination preference and visual orientation of wild-reared mice, Peromyscus leucopus

A two-phase study was conducted with Peromyscus leucopus noveboracensis. In the field, frequency of captures was examined relative to nocturnal cloud cover and moon visibility. No relationships were apparent. In the laboratory, preferences of wild-reared mice for opposing visual cues under contrasting levels of illuminance were studied. Mice preferred an illumination equivalent to that striking a field on a clear, moonlit night (0.020 foot-candle) to the average of that striking the forest floor on a cloudy, moonlit night (0.005 foot-candle). At the lower intensity, mice showed no preference between two identical boxes placed vertically or horizontally. At the higher level of illuminance, there was a preference for the horizontal box, suggesting a tendency to orient toward horizontal objects over vertical ones at certain light levels. Higher natural nocturnal illuminance is not avoided (and may actually be preferred) by P. leucopus. Vision may be an important sensory modality in orientation and navigation under these conditions.     

Patterns of parental care in two cricetid rodents, Onychomys torridus and Peromyscus leucopus

Daily observations were made of the maternal and paternal behaviour of Onychomys torridus and Peromyscus leucopus in laboratory cages. In both species, the females spent more time in the nest area with the young and groomed the young more frequently than their male partners, but the males played a surprisingly active role in nest attendance. Paternal nest attendance was more frequent in O. torridus males than in P. leucopus males. Onychomys males were also more active in grooming the young than Peromyscus males. These species-specific patterns of parental care are discussed in relation to the behavioural and ecological characteristics of Onychomys and Peromyscus.     

Insulins,leptin and feeding in a population of Peromyscus leucopus (white-footed mouse) with variable fertility

This article is part of a Special Issue “Energy Balance”.     

The comparative susceptibilities of Pieris brassicae and P. rapae to a granulosis virus from P. brassicae

A comparison was made of the dosage-mortality responses of larvae of Pieris brassicae and P. rapae to infection by P. brassicae granulosis virus (GV). Bioassays with first, second, third, and fourth-instar larvae of both species revealed a marked difference in susceptibility between instars and between species. Median lethal dosages (LD₅₀s) for P. rapae larvae ranged from five capsules for the first instar to 662 capsules for the fourth instar. With P. brassicae, this range extended from 66 capsules to 2.3 × 10⁷ capsules. The time-mortality responses of the two species were similar when fed virus dosages equivalent to an LD₉₀. Median lethal times (LT₅₀s) ranged from 5 days for first-instar larvae to 7–8 days for fourth-instar larvae. A comparison between a long-established laboratory stock of P. brassicae and a stock recently acquired from the field showed no significant difference in their susceptibility to GV. The implications of the pronounced species differences in susceptibility to GV infection are discussed in relation to the potential field control of P. rapae and P. brassicae.     

Multiplex real-time PCR detection of P. falciparum, P. vivax and P. malariae in human blood samples

Two duplex real-time PCR assays were developed to diagnose three human parasites: Plasmodium falciparum, Plasmodium vivax and Plasmodium malariae. TaqMan duplex real-time PCR was evaluated in 263 blood samples of suspected malaria patients by comparing results against those obtained with microscopy and nested PCR. Compared with nested PCR, duplex real-time PCR assays showed 100% sensitivity and specificity. Duplex real-time PCR detected all mixtures of P. falciparum and P. vivax DNA, except at threshold detection limits for both parasites in which P. vivax was not amplified. Threshold detection limits of real-time PCR were 3.1, 0.3 and 0.8 parasites per microlitre of blood for P. falciparum, P. vivax and P. malariae, respectively. Duplex real-time PCR allows the detection of malarial cases, including mixed species infection, it simplifies analysis and reduces cost. Thus, this protocol may prove invaluable for use in the diagnosis of human infection, trial treatments and epidemiologic studies in which high-throughput analyses are often required.     

Coumarins from Pterocaulon balansae and P. lanatum

Analysis of the petrol-diethyl ether extracts of Pterocaulon balansae and P. lanatum aerial parts afforded, besides puberulin, scopoletin-[2′     

Transcriptional analysis of Pieris rapae in response to P. rapae granulovirus

Pieris rapae granulovirus (PrGV) is an important pathogen that has been exploited as a microbial insecticide to control agriculture pests. They can specifically infect cabbage butterfly (Pieris rapae), causing a series of pathological symptoms. In this infected P. rapae at 6?h and 72?h. As a result, a series of host genes were significantly modulated following PrGV infection, including those correlated with exoskeleton, ribosome, heat shock protein (HSP), proteasome, oxidation-reduction and apoptosis. Taken together, our study unveiled the P. rapae response to PrGV at different time point and provided a potential strategy for pest management.     

Further diterpenoids from Plectranthus ornatus and P. grandidentatus

A new halimane diterpenoid and the previously known labdane rhinocerotinoic acid were isolated from Plectranthus ornatus Codd. In addition, a new monoacetyl derivative of the abietane coleon U was found among the constituents of Plectranthus grandidentatus Gürke. These diterpenes could be significant from both chemotaxonomic and biogenetic points of view.     

Bound forms of alkaloids in Papaver somniferum and P. Bracteatum

The polysaccharide fraction of the pericarp and seed of Papaver somniferum were shown to contain bound forms of morphine which were derived from radioactive morphine fed to living plants. Bound forms of codeine, thebaine and some unidentified alkaloid-like compounds were also detected in the pericarp and bound thebaine occurred in the pericarp of Papaver bracteatum. The complexity and molecular weight of the bound alkaloids seemed to increase during ripening, and it is suggested that these substances represent transitional forms in the metabolism and transiocation of morphine from latex to seed.     

Serological evidence confirming the assignment of phaseolus aureus and P. mungo to the genus vigna

Endopeptidase activity was detected in extracts of cotyledons of 11 species of Vigna and Phaseolus Antibodies against the purified protease isolated from the cotyledons of 5-day-old P.aureus seedlings inhibited the activity of that enzyme in crude extracts of cotyledons. A similar inhibition was obtained with P. mungo, P. adenanthus and 4 species of Vigna, while there was no inhibition of endopeptidase activity in extracts of cotyledons of 4 species of Phaseolus. Immunodiffusion tests proved that the protease of Vigna is distinct from that of Phaseolus. The evidence supports the reassignment of P. aureus and P. mungo to the genus Vigna and indicates that the names Vigna radiata and Vigna mungo are more appropriate than P. aureus and P. mungo for green gram and black gram respectively.     

Effects of social interaction on eating and drinking in two subspecies of deermice, Peromyscus maniculatus bairdii and Peromyscus maniculatus gracilis

Pair combinations of Peromyscus maniculatus bairdii and Peromyscus maniculatus gracilis were given access to solid food and water or 8 per cent sucrose. All groups consumed more total calories under separate housing conditions than when the pair was housed together. No differences were found among the three cominations of subspecies, and cage size was not a significant variable. These results suggested testing Zajonc's theory of social facilitation, which states that the intensity of the most salient response increases in the presence of conspecifics at the expense of less probable responses. In the second experiment drinking was made the most salinet behaviour by placing the mice under 23-hr liquid deprivation. Contrary to theoretical predictions social inhibition was again demonstrated.     

Flavonol tetraglycosides from the leaves of Prunus cerasus and P. Avium

Four new flavonol glycosides have been identified from fresh leaves and fruits of sweet and sour cherries (Prunus avium and P. cerasus) as minor flavonoids: quercetin 3-O-rutinosyl-7,3′-O-bisglucoside; two quercetin 3-O-rutinosyl-4′-di-O-glucosides; kaempferol 3-O-rutinosyl-4′-di-O-glucoside.     

Mating behavior of Philophthalmus megalurus and P. gralli in concurrent infections of chicks

Nollen P. M. 1984. Mating behavior of Philophthalmus megalurus and P. gralli in concurrent infections of chicks. International Journal for Parasitology14: 71–74. Mating patterns were determined in concurrent infections of the eyeflukes of birds, Philophthalmus megalurus and P. gralli, by detection of ³H-tyrosine-labeled sperm on autoradiograms. When labeled P. megalurus adults were transplanted singly with unlabeled P. gralli adults, interspecies mating took place. When both unlabeled P. gralli and P. megalurus were transplanted with single labeled P. megalurus, sperm were transferred to both species. However, the insemination rate of P. gralli was much lower than when unlabeled P. meglaurus adults were absent. Labeled P. gralli transplanted singly with unlabeled P. megalurus or unlabeled adults of both species did not show interspecies mating, but carried on intraspecies mating at a normal rate. A low rate of self-insemination was observed in labeled worms when the opposite species was present, but not when the same species was present. Evidence for interspecies fertilization and hybridization between P. megalurus and P. gralli was not found.     

Enzymic reduction of codeinone in vitro cell-free systems from Papaver somniferum and P. Bracteatum

Cell-free extracts have been prepared from Papaver somniferum which catalyze the reduction of codeinone-[16-³H] to codeine. The methodology for examining this conversion has pointed to conditions for exploring the preparation of suitable enzyme extracts. P. bracteatum also yielded a cell-free system which reduced codeinone to codeine, both of which are foreign to this species.     

Prenylated hydroquinones: contact allergens from trichomes of Phacelia minor and P. parryi

Geranylgeranylhydroquinone and 1-oxofarnesylhydroquinone were identified as contact allergens in trichomes of Phacelia minor and P. parryi.