bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECTS OF TEMPERATURE ON DEVELOPMENTAL RATE AND ADULT WEIGHT OF AUSTRALIAN POPULATIONS OF ACYRTHOSIPHON PISUM (HARRIS) (HOMOPTERA: APHIDIDAE)
Authors: Lamb Robert J. , MacKay Patricia A.
Published: April 2011

Three populations of the pea aphid, Acyrthosiphon pisum (Harris), from locations between 27 and 36°S in eastern Australia were studied at five constant temperatures from 10 to 28 °C. A three-parameter, nonlinear equation accurately described developmental rate as a function of temperature for each of the five lines from each population. Maximum adult weight was attained at 20 °C. Wingless aphids developed faster and were heavier than winged aphids. There were no significant differences in developmental times among populations, and adult weights among populations differed only at 25 °C. These weight differences and other nonsignificant differences among populations showed no trends with the long-term average temperatures at the collection sites. This finding indicates that developmental rate and adult weight have not been adapted to temperature in the 5 years since the aphids were introduced. The maximum rate of development, optimum temperature for rapid development, developmental threshold, and optimum temperature for high adult weight were higher for the Australian populations than for North American populations, but these differences do not reflect adaptation to different environmental temperatures. We conclude that Australian populations of A. pisum did not originate in North America.
INDIVIDUAL FOOD CHOICES BY FORAGERS FROM THE SPECIES ACROMYRMEX OCTOSPINOSUS (REICH), THE LEAF-CUTTING ANT
Authors: Therrien Pierre
Published: April 2011

Foragers from the species Acromyrmex octospinosus (Reich) were given a choice between four different plant discs in the laboratory: Manihot esculenta (Crantz.) (cassava) varieties A and B; Ipomea batatas (L.) (sweet potato); and Dioscorea cayenensis cayenensis (Lam.) (yellow yam). Disc pick-up was not random among 8 of 11 individual foragers nor for the whole colony. Variations in preference were observed between days of the experiment and between foragers for the same day. Some foragers were not seen every day of the experiment. Variations between foragers might be an effect of age or genetic make-up. The existence of such variation may be adaptive for the colony as it ensures a better sampling of the plants available around the nest and avoids problems that would arise from the disappearance of a plant if it were the exclusive source of substrate for the colony.
STRESS SPECIFICITY OF MATERNAL EFFECTS IN HELIOTHIS VIRESCENS (BODDIE) (LEPIDOPTERA: NOCTUIDAE) LARVAE
Authors: Gould F.
Published: April 2011

Quercetin, a growth-inhibiting compound that is produced by many plants, was incorporated into an artificial diet and fed to Heliothis virescens (Boddie) larvae. Eggs were collected from females that had developed on this diet and from females that had developed on unadulterated artificial diet. Neonates from these eggs were placed on diets containing quercetin or other commonly occurring plant compounds (rutin, gossypol, gramine). Offspring from parents that had developed on quercetin-containing diet grew more slowly on diets containing quercetin, rutin, or gossypol, than did larvae from parents reared on unadulterated diet. Larvae from both types of parents grew at the same rate when reared on gramine-containing diet. Maternal, but not paternal, diet led to decreased growth of offspring on quercetin-containing diet. When reared on quercetin- and rutin-containing diets, offspring from parents that had developed on tobacco or soybean grew more slowly than larvae from parents reared on unadulterated diet.
INSECTS IN THERMAL SPRINGS
Authors: Pritchard Gordon
Published: April 2011

Thermal springs are characterized by year-round high temperatures and a total-dissolved-solids concentration that is generally higher than that of surface waters. Insects appear to encounter few constraints from the water chemistry of most thermal springs, but considerable constraint from the high water temperature. Indeed, because no insect lives above 50 °C and very few above 40 °C, few thermal springs offer favorable conditions for insects in the actual boil itself. Thermal spring insects live in the stream at some distance from the source, and they may be defined as living in habitats having temperature regimens that are influenced by geothermy in the sense that they are warmer than they otherwise would be. An annual mean water temperature that is 5 °C above the annual mean air temperature of the region can be used to define the downstream limit of geothermal influence.Thermal springs around the world have similar insect faunas; only four orders (Diptera, Coleoptera, Hemiptera, Odonata) are commonly represented, and each of these only by a handful of genera. Furthermore, the fauna of any one thermal spring is characterized by very few species, and the higher the temperature the lower the species richness. Both temperature and water chemistry may exclude certain species, and even whole orders, from thermal springs, these factors acting either directly, alone or in concert, or indirectly through competitive interactions. Even moderately warmed systems can significantly affect insect growth rates, and seasonal regulation of adult emergence through diapause is a common strategy of temperate-zone thermal spring insects.Thermal springs present many advantages to the ecologist, such as long-term habitat constancy, temperature stability, and taxonomic simplicity. They provide field laboratories for the study of temperature-related phenomena as well as the opportunity to explore a range of questions in biogeography and evolutionary biology. The challenge is to form the questions and select the systems critically.
AQUATIC COLEOPTERA OF SPRINGS IN CANADA
Authors: Roughley R.E. , Larson D.J.
Published: April 2011

The habitat preferences of each of the 663 species of aquatic Coleoptera known from Canada and Alaska were categorized as lentic, lotic, spring-inhabiting, other, or unknown. Most species were assigned to a single habitat type although some occur in more than one habitat. The distribution of species among these habitat types is as follows: lentic, 61%; lotic, 23%; springs, 8%; other, <1%, unknown, 8%. The 63 spring-inhabiting species are distributed among the families Dytiscidae (38 species), Hydrophilidae (nine), Hydraenidae (eight), Chrysomelidae (subfamily Donaciinae) (six), Haliplidae (one), and Dryopidae (one). The diversity of these families in springs only approximately parallels their diversity in the total fauna. Several relatively diverse families (Gyrinidae, Scirtidae, and Curculionidae) are absent from springs as are some predominantly lotic families (Amphizoidae, Elmidae, and Psephenidae). About half the spring species are western (occurring in Manitoba and west), about a quarter are eastern, and a quarter are transcontinental. Most of these spring species are known from the conterminous United States and it is suggested that spring habitats within Canada are being colonized slowly from southern refugia.The habitat affinities of spring-inhabiting Dytiscidae are examined in detail. Of the 260 species occurring in Canada, 38 species occur in springs and represent about 60% of all beetle species in Canadian springs. The spring fauna of dytiscids comprises four elements: nine (24%) inhabit springs only, 11 (29%) are lotic species that also occur in springs, 12 (31%) are species that use a broad range of habitats, and six (16%) are species known otherwise only from lentic habitats. The dytiscid fauna of springs is a heterogeneous assemblage derived from many separate phylogenetic elements.
A COMPARISON OF THE SPRING-INHABITING GENERA OF CHIRONOMIDAE FROM THE HOLARCTIC WITH THOSE FROM NATURAL AND MANMADE SPRINGS IN LABRADOR, CANADA
Authors: Colbo M.H.
Published: April 2011

From the literature 70 of the 212 chironomid genera known in the immature stage from the Holarctic Region are considered in this paper to be inhabitants of springs or seeps, or both. Three more are known only from adults collected at springs and seeps so that 73 out of 235 genera recognized from the Holarctic appear to be associated with these habitats. Literature records of distribution suggest that 65 of the 73 occur in northeastern North America. Collections from natural and manmade springs and seeps in Labrador yielded 45 genera; 40 of these genera belong to the set of 65 genera noted above. The other five are likely spill-overs into springs and seeps from adjacent habitats. Communities from manmade springs and seeps originating from the earth dykes and dams at Churchill Falls were compared with natural springs and seeps there and in Goose Bay, Labrador. Chironomid communities were similar at the generic level in both man-made and natural spring–seep habitats.
ARTHROPODS OF SPRINGS, WITH PARTICULAR REFERENCE TO CANADA: SYNTHESIS AND NEEDS FOR RESEARCH
Authors: Danks H.V. , Williams D. Dudley
Published: April 2011

Springs include a great variety of habitats, because many possible geological and ecological conditions intersect in any given spring.Available information on the arthropod fauna shows that springs contain a limited number of species of diverse origins, including groundwater, stream, and water-film inhabitants. There is a substantial number of spring-specialist species, many of them in distinctive genera, reflecting many independent invasions of spring habitats by various groups and subgroups of aquatic arthropods. Most of this diversity is present in cold water springs, though smaller numbers of distinctive elements occur in hot or in saline springs. The specialists of coldwater springs tend to show adaptations such as cold stenothermy and limited dispersal, but different species possess different suites of adaptations to the habitat, reflecting their evolutionary history and biology.Faunal differences among springs result from geographical differences (many species, though not as many genera, differ between eastern and western Canada), but within a given region reflect the variety of habitats and microhabitats that exists. Such variety means that except in very broad terms it is not possible to establish workable “definitions” for the range of spring types. Rather, we recommend that biologists adopt a few key descriptors, based on source geometry, water supply, temperature, chemistry, and persistence, to provide useful information about the sites in which they collect. The term “spring” should be used conservatively, to apply only to the area immediately around the point of groundwater issue, because conditions change rapidly farther away from this point.Some needs for the inventory (and protection) of springs and for more extensive sampling are summarized. Further taxonomic studies are required in several characteristic groups. Ecological work on the specialized species confined to springs is likely to be especially instructive.
DIVERSITY OF SOIL ARTHROPODS IN CANADA: SYSTEMATIC AND ECOLOGICAL PROBLEMS
Authors: Behan-Pelletier Valerie M.
Published: April 2011

Data on diversity are fundamental to our understanding of both natural and disturbed ecosystems. Yet, despite their real and potential importance, knowledge of the diversity of non-pterygote soil arthropods in Canada still is very incomplete. This is illustrated with information on diversity from nine non-pterygote arthropod taxa: Tardigrada, Chilopoda, Diplopoda, Symphyla, Pauropoda, Protura, Collembola, Pseudoscorpionida, and Oribatida, and faunal lists are given for six of these taxa. Although valuable family and generic keys have been published recently, few monographic works or user-friendly keys to species are available. Autecological information essential to explaining the functional role of soil arthropods remains inadequate. Fortunately, the needs of other disciplines and issues are causing a change. For example, current ecological research recognizes that the roles of soil arthropods in decomposition, nutrient cycling, and soil formation are more complex than previously supposed, palaeoecologists require new or corroborating data to interpret their fossil assemblages, and issues such as agroecosystem management, environmental indicators, and global change require a more thorough knowledge of soil communities. Researchers in these areas face poor data on diversity based on inadequate systematics, which limit their understanding of the composition and organisation of soil arthropod communities. This inadequacy presents both a challenge and an opportunity to soil arthropod systematists and ecologists.
PATTERNS OF DIVERSITY IN THE CANADIAN INSECT FAUNA
Authors: Danks H.V.
Published: April 2011

The diversity of the Canadian insect fauna decreases and its composition (at all taxonomic levels) changes as climates become progressively more harsh toward the north. This climatic trend dominates patterns of diversity, but many other factors interact to produce the observed patterns. In the arctic, species richness is greatest in the west. Farther south, overall species richness is greatest in the west (especially British Columbia), associated with coastal and cordilleran habitats, and to a somewhat smaller degree in the southeast (especially Ontario), associated with deciduous forests and particularly with transitional forests which occupy a large area of southeastern Canada. However, certain taxa are better represented in the west or in the east, depending on present-day habitats and on historical factors. These conclusions, based chiefly on a sample of taxa of different types, are possible only because basic systematic work has been carried out to distinguish and map the species. Preliminary data on numerical patterns, such as the numbers of species relative to different potential resources such as host plants in different zones, tend to suggest that the occurrence of species in the north may depend so heavily on climatic factors that potential resources are not fully exploited and the effects of interspecific interactions on diversity are reduced.
WEEVILS AND PLANTS: PHYLOGENETIC VERSUS ECOLOGICAL MEDIATION OF EVOLUTION OF HOST PLANT ASSOCIATIONS IN CURCULIONINAE (COLEOPTERA: CURCULIONIDAE)
Authors: Anderson Robert S.
Published: April 2011

A great proportion of biodiversity is accounted for by organisms, particularly insects, intimately associated with plants. Knowing whether ecological or phylogenetic factors chiefly influence the evolution of host plant associations is essential to understanding speciation in, and therefore factors influencing diversity of, phytophagous insects. Through examination of known host plant associations in Curculioninae and comparison with available reconstructed phylogenetic relationships of certain taxa of Curculioninae, little, if any, evidence for cospeciation (parallel cladogenesis) is found. In curculionine taxa where sufficient host plant and/or phylogenetic data are available, weevil species are narrowly to broadly oligophagous; a number of related weevil species are associated with a single host plant species; many weevil genera have host plant ranges spanning distantly related plant taxa; and available weevil reconstructed phylogenies are not concordant with plant relationships. Rather, for at least some weevil taxa, evolution appears to be mediated by one or more of a variety of strictly ecological factors, particularly habitat associations. General applications of these results include biological control, pollination biology, conservation and restoration biology, and use of patterns in insect – host plant associations to resolve problems in plant classification.
EVOLUTION OF LIMOTETTIX SAHLBERG (HOMOPTERA: CICADELLIDAE) IN PEATLANDS, WITH DESCRIPTIONS OF NEW TAXA
Authors: Hamilton K.G.A.
Published: April 2011

The world species of Limotettix Sahlberg are reviewed, and 13 new Nearctic species are described: in the typical subgenus — L. conservatus; in the new subgenus Dryola — L. elegans, L. minuendus; in subgenus Neodrylix — L. urnura; in subgenus Ophiolix — L. nigristriatus, L. pseudosphagneticus, L. xanthus; and in subgenus Scleroracus — L. brooksi, L. medleri, L. obesura, L. scudderi, L. strictus, and L. zacki. Limotettix (L.) emeljanovi is proposed to replace L. luteolus Emel'janov, 1962, nec L. (Scleroracus) luteolus (Sleesman, 1930). The 80 known world species are arranged phylogenetically. From this analysis the genus evidently evolved in the New World from swale and fen inhabiting ancestors that fed on spike-rush. Their bog-inhabiting descendents fed on various rushes and sedges, but apomorphic lineages transferred to ericaceous plants. Adaptation to ericaceous plants permitted invasion of drier habitats, with subsequent radiation on other semiwoody plants, principally Asteraceae and Symphoricarpos.
THE BEETLE FAUNA OF A MATURE SPRUCE–SPHAGNUM BOG, ALGONQUIN PARK, ONTARIO; ECOLOGICAL IMPLICATIONS OF THE SPECIES COMPOSITION
Authors: Runtz M.W.P. , Peck Stewart B.
Published: April 2011

The beetle (Coleoptera) fauna of a black spruce [Picea mariana (Mill.) BSP] – tamarack [Larix laricina (DuRoi) K. Koch] – Sphagnum bog in Algonquin Provincial Park, Ontario, was sampled from early June to mid-August with yellow pan traps and emergence traps. The yield was 5734 beetles, in 30 families. Ptiliidae was the most numerically abundant and Staphylinidae was the most taxonomically diverse. Carabidae was second in diversity and third in numerical abundance. The abundance and ecological implications of some individual species are discussed. Few of the species are bog-specific. The faunal composition suggests that the bog is in a late-succession phase and that most of the beetle species are derived from adjacent habitats.
TERRESTRIAL ARTHROPODS OF CANADIAN PEATLANDS: SYNOPSIS OF PAN TRAP COLLECTIONS AT FOUR SOUTHERN ONTARIO PEATLANDS
Authors: Blades David C.A. , Marshall Stephen A.
Published: April 2011

This report is a synopsis of the terrestrial arthropod faunas collected from four peatlands in southern Ontario. The peatlands surveyed were the Wylde Lake bog (43°55′N, 80°30′W), Crieff fen (43°25′N, 80°07′W), Oliver bog (43°20′N, 80°16′W), and the Wainfleet bog (42°55′N, 79°17′W). Arthropods were collected in yellow pan traps (aluminum pan traps at Wainfleet) during the period May 1987 to June 1988 (including the period of snow cover from December to March). A total of 33 029 specimens were removed from the pan trap samples and of these 17 173 individuals were assigned to species. Between 603 and 870 species of arthropods were identified from each site. Collections from each site were compared using taxonomic and ecological groupings (based on feeding behaviour and habitat preference) of species. Sorensen's Index of Similarity was used to compare the overlap of species among sites. The Hymenoptera, Diptera, Coleoptera, and Araneae were the most species-rich orders collected at each site. More species preferring peatlands were collected at each of the three undisturbed peatlands (Wylde L., Crieff, and Oliver) than at the mined bog, Wainfleet. Species not usually associated with peatlands were more numerous in the Wainfleet collection than in collections from the undisturbed sites. It is concluded that grouping of species by habitat preference is a useful technique for assessing habitat disturbance.
FORMULATION OF ENTOMOPATHOGENS FOR THE CONTROL OF GRASSHOPPERS AND LOCUSTS
Authors: Moore D. , Caudwell R.W.
Published: April 2011

Successful development of a biological pesticide requires attention not only to the biological agent, but also to formulation, application, and the biology of the pest–pathogen interaction in the field. Emphasis in our review is given to fungi, Metarhizium spp. and Beauveria bassiana (Balsamo) Vuillemin, as the most suitable agents, and oil-based ULV formulations or baits as the most promising application techniques for use with locusts and grasshoppers. The efficacy of the pathogen isolate must be maximized; selection is aimed at those that are suitably virulent, specific, and well adapted to the relevant environmental conditions. Opportunities exist for manipulation of the characteristics of the isolate by genetic means and by developments in culturing techniques. Formulation requirements are stability during storage and the ability to carry the active ingredient successfully to the target insect at application. Likely storage methods for fungi would be as dry conidia, perhaps with clay diluents, or in oils; the characteristics of both are briefly discussed. At application, efficacy of dose transfer and protection of the biological agent against environmental constraints such as UV radiation are needed. Baits have advantages in terms of dose transfer but logistical problems associated with the bulkiness of the carrier remain. Technological advances, including those that offer the prospect of carrier production in situ from dense precursors, and better knowledge of feeding behaviour have improved the prospects for baits. Multi-disciplinary research reducing dependency on the biological agent and exploiting formulation chemistry and application technology is required in developing biological pesticides.
METHODS OF APPLICATION OF MICROBIAL PESTICIDE FORMULATIONS FOR THE CONTROL OF GRASSHOPPERS AND LOCUSTS
Authors: Bateman Roy
Published: April 2011

The use of chemical insecticides, especially as ultra low volume (ULV) formulations, against locusts and grasshoppers will continue for the foreseeable future; therefore application techniques for microbial agents should be as compatible as possible with existing practice. Low volume and ULV spraying of deuteromycete conidia in oil-based formulations have produced very promising acridid control results in the field, although baiting, dusting, and hydraulic application techniques have also been tested for a wide range of pathogens.The key problems for further research and development appear to be the logistics and supply of consistently reliable formulations for application on a large scale, and the determination of mechanisms for effective dose transfer in the field. The application of suspended particulate matter can present special problems with rotary and other atomizers.
ENTOMOPOXVIRUSES ASSOCIATED WITH GRASSHOPPERS AND LOCUSTS: BIOCHEMICAL CHARACTERIZATION
Authors: Erlandson M.A. , Streett D.A.
Published: April 2011

Entomopoxviruses (EPVs) are large DNA viruses with structural similarities to vertebrate poxviruses. EPV virions are occluded in large (3–15 μm in diameter) proteinaceous occlusion bodies (OBs). To date, EPVs are reported from 15 species of grasshoppers and locusts. The current information on the biochemical characterization of these EPVs is summarized in our review. The DNA genomes of grasshopper and locust EPVs analysed to date have a G+C ratio of approximately 18.5% and genome size estimates generated by various methods range from 180 to 194 kilobase pairs (kbp). Restriction endonuclease enzyme analysis of a number of grasshopper and locust EPV DNAs shows the virus isolates to be distinct and the technique will be useful in identifying virus isolates. The structural proteins of certain grasshopper EPVs have also been analysed. Forty to 50 polypeptides ranging in molecular weight from 12 to 200 kilodaltons (kDa) have been detected by SDS-PAGE analysis of virions released from OBs and the polypeptide profiles are distinct for many of the virus isolates. The proteinaceous matrix of the OB of EPVs contains one predominant protein referred to as spheroidin. The spheroidin protein from most grasshopper EPVs is approximately the same molecular weight, 107 kDa, when analysed by SDS-PAGE. As with other groups of occluded insect viruses, grasshopper EPVs have a protease activity associated with OBs derived from infected insects. The possible role of this protease activity in the infection cycle is discussed. Finally, the role of various molecular techniques for the detection and identification of EPV infections in laboratory and field populations of grasshoppers and locusts is discussed. The development of EPV-specific monoclonal antibodies and DNA hybridization probes for the detection of virus infections is reviewed. As well, the possible use of polymerase chain reaction and randomly amplified polymorphic DNA fingerprinting techniques for the detection and identification of EPV infections is discussed.
The Comparative Internal Larval Anatomy of Sawflies (Hymenoptera: Symphyta)
Authors: Maxwell Doreen E.
Published: April 2011

Examination of 132 recognized species of sawflies (Hymenoptera: Symphyta) from America, Europe, Africa, and Australia, has demonstrated the value of internal anatomical larval detail as a taxonomic tool and an indicator of phylogenetic relationship. Two characters, the salivary glands and Malpighian tubules, proved of major importance. The salivary glands fall into three main categories, narrow squared ducts and incorporated gland cells (the Orthandria with the exception of the Xyelidae), narrow ducts and sheathlike gland cells (the Xyelidae), and either increased cell numbers and narrow branching ducts or expanded ducts (the Tenthredinoidea). Three divisions of the Tenthredinidae are suggested, viz. the Selandriinae-Dolerinae-Athaliinae-Lycaotinae, the Nematinae, and the Blennocampinae-Allantinae-Heterarthrinae-Tenthredininae, corresponding to Malpighian tubule groupings of primitive, intermediate-advanced, and advanced. Character trends are discussed in the light of existing adult arrangements (Ross and Benson), and external larval (Yuasa). The survey emphasizes the need of a revision of family and subfamily limits. Where identification is difficult, internal anatomy is of use in determination to genus and species as well as to family and subfamily. The frequency of parallel evolution does not affect the use of certain characters indicative of progressive change within a group.
Adult Elateridae of Southern Alberta, Saskatchewan and Manitoba (Coleoptera)
Authors: Brooks A. R.
Published: April 2011

Illustrated keys and descriptions of 26 genera and 137 species or subspecies of Elateridae of southern Alberta, Saskatchewan and Manitoba are presented. The distribution of each species is described in relation to the bio-ecological regions in the three Provinces. No new species are described.
Recherches sur la Biologie et la Dynamique des Populations Naturelles d'Archips argyrospilus(Wlk.) (Lépidoptères: Tortricidae) dans le Sud-ouest du Québec
Authors: Paradis Rodolphe-O. , LeRoux E. J.
Published: April 2011

Des recherches bio-écologiques ont été en cours de 1956 à 1963 surArchips argyrospilus(Wlk.), tortricidé qui infeste périodiquement les pommiers dans le sud-ouest du Québec.Le cycle évolutif complet, tel que déterminé, révèle que l'espèce est univoltine et passe l'hiver au stade d'œufs. L'éclosion larvaire prend place vers le milieu de mai et présente un synchronisme évident avec les premiers stades phénologiques du pommier. La nymphose débute vers la mi-juin, tandis que les adultes éclosent jusqu'au 20 juillet.Les études écologiques, constituant une des premières utilisations des 'tables de survie' en relation avec les insectes des cultures, portent sur sept générations successives qui s'intègrent dans la durée complète d'une pullulation. Le taux annuel de mortalité, chez les populations d'A.argyrospilus, varie de 91.3 à 99.7 pour cent et résulte de l'action conjuguée de nombreux facteurs biotiques et abiotiques. Les mouvements de progression et de régression de la présente pullulation ont cependant été réglés, d'une part, par les migrations d'adultes, conditionnées par l'environnement et, d'autre part, par l'action des oiseaux et du parasiteItoplectis conquisitor(Say) sur la survie des chrysalides, facteurs trouvés dépendants de la densité de l'hÔte.
A new species of Arthula (Hymenoptera: Ichneumonidae: Cryptinae) from Korea, and its intraspecific seasonal variation
Authors: Oh Seung-Ho , Lee Jong-Wook , Choi Won-Young
Published: April 2011

A new species, Arthula biformis Oh and Lee sp. nov., belonging to the cryptine ichneumonid subtribe Sphecophagina Beirne is described from Korea. The new species is composed of two seasonal forms, overwintering and summer, distinguished by color and some morphological features. The overwintering form is much darker than the summer form. Keys to the genera of Sphecophagina and the known species of Arthula Cameron and photographs of diagnostic characters of both color forms of the new species are provided.
Optimization of duplex real-time PCR with melting-curve analysis for detecting the microsporidian parasites Nosema apis and Nosema ceranae in Apis mellifera
Authors: Burgher-MacLellan Karen L. , Williams Geoffrey R. , Shutler Dave , MacKenzie Kenna , Rogers Richard E.L.
Published: April 2011

Honey bees, Apis mellifera (L.) (Hymenoptera: Apidae), are parasitized by the microsporidians Nosema apis (Zander) and Nosema ceranae (Fries). Molecular techniques are commonly used to differentiate between these parasites because light microscopy is inadequate. Our objectives were to (i) adapt the previously published duplex polymerase chain reaction (PCR) targeting the 16S rRNA gene of N. apis (321APIS-FOR, 321APIS-REV) and N. ceranae (218MITOC-FOR, 218MITOC-REV) using qualitative real-time PCR assay with SYBR® Green I dye (R-T PCR) and DNA melting-curve analysis, and (ii) determine whether the two Nosema species can be detected simultaneously in honey bees. Total spore counts and purified total genomic DNA were obtained from 37 bee samples (19 individual workers and 18 pooled samples of 15 workers) collected in Nova Scotia, Prince Edward Island, and Newfoundland, Canada. Overall, the prevalence of Nosema species was 86.5% (32/37 samples of bee DNA), based on conventional PCR and the optimized R-T PCR assay. The melting-curve analysis showed three groups of curve profiles that could determine the prevalence of N. apis, N. ceranae, and co-infection (21.9%, 56.2%, and 21.9%, respectively). The duplex R-T PCR assay was efficient, specific, and more sensitive than duplex conventional PCR because co-infection was identified in 5.4% (n = 2) more samples. Sequencing of R-T PCR products confirmed the results of the melting-curve analysis. Duplex R-T PCR with melting-curve analysis is a sensitive and rapid method of detecting N. apis, N. ceranae, and co-infection in honey bees.
Braconid parasitoids (Hymenoptera: Braconidae) of NearcticChoristoneuraspecies (Lepidoptera: Tortricidae), with a summary of other parasitoid families attackingChoristoneura
Authors: Fernández-Triana J. L. , Huber J. T.
Published: April 2011

Illustrated identification keys are given for the superfamilies/families of insect parasitoids and the subfamilies, genera, and species of Braconidae reared from species ofChoristoneuraLederer in the Nearctic Region.Goniozus floridanus(Ashmead) (Chrysidoidea: Bethylidae) represents the third superfamily of Hymenoptera, andColpoclypeus florus(Walker) (Hymenoptera: Eulophidae) is added to the list of Chalcidoidea recorded fromChoristoneura. Fifty species of Braconidae in 18 genera and 9 subfamilies are recorded parasitizing 11Choristoneuraspecies; almost half belong to the Microgastrinae. Eight braconids (16%) were found for the first time as parasitoids ofChoristoneura. The first host record is given forOncophanes californicus(Ashmead) (Hormiinae). Known insect parasitoids ofChoristoneuraspp. in the Nearctic Region include 230 species in 106 genera, about 75% of which attack only 1 or 2Choristoneuraspecies each. An additional 36 species are considered incorrectly associated withChoristoneura, an error rate of 14%. The Banchinae (Ichneumonidae, especiallyGlyptaGravenhorst), Pimplinae (Ichneumonidae), and Microgastrinae (Braconidae) made up the greatest proportion of parasitoids. No parasitoids have yet been recorded from five NearcticChoristoneuraspecies.
Molecular evidence for sympatric taxa withinPemphigus betae(Hemiptera: Aphididae: Eriosomatinae)
Authors: Foottit R. G. , Floate K. , Maw E.
Published: April 2011

Mitochondrial DNA cytochromecoxidase subunit 1 (DNA barcode) and nuclear microsatellite flanking region sequences were used to analyse populations of putative “sugarbeet root aphid”,Pemphigus betaeDoane, from sites in Alberta, Canada. Three sympatric genotypes were revealed, identified asP. betae,P. populivenaeFitch, and an undetermined third species. All three genotypes formed morphologically indistinguishable galls on the same set of cottonwood (PopulusL., Salicaceae) host species, often on the same tree. Gall morphology is frequently used to identifyPemphigusspecies. Our results indicate that this practice may be unreliable for these three taxa at least.
Presence of fed β-carotene in digesta, excreta, blood, and hepatic and adipose tissues of Holstein steers
Authors: Mora O. , Romano J. L. , González E. , Ruiz F. J. , Gómez R. , Shimada A.
Published: April 2011

Eight animals were fed a diet without added β-carotene for 49 d and then supplemented with four levels of β-carotene (0, 5.5, 44 or 352 mg kg–1dry matter) for 30 d; the two-phase procedure was then repeated. Steers were killed at the end of the second period. Concentrations of β-carotene were: 0, 0, 227.2 and 2011 mg dL–1 (P < 0.05) in ruminal fluid; 0, 0, 533.7 and 4418 mg dL–1 (P < 0.05) in duodenal fluid; 0, 4.03, 14.91 and 90.64 mg g–1 (P < 0.05) in dry faeces; 0.8, 1.2, 4.7 and 8.1 mg g–1 (P < 0.05) in liver; 0.07, 0.15, 0.5 and 3.7 mg g–1 (P < 0.05) in subcutaneous fat; 0, 0, 0.09 and 0.23 mg g–1 (P < 0.05) in kidney fat for dietary treatments with 0, 5.5, 44 and 352 mg β-carotene kg–1 DM, respectively. The dose of β-carotene was reflected in retinol concentrations in liver: 101.1, 113.6, 161.7 and 199.6 mg g–1 (P < 0.05), but not in subcutaneous or kidney fat (P > 0.1). The estimated β-carotene digestibilities were 66.25, 84.39 and 88.14% for treatments with 5.5, 44 and 352 mg β-carotene kg–1 DM, respectively (P < 0.01). The results suggest a high capacity of bovine tissues to store β-carotene and probably a limited capability to convert β-carotene into vitamin A. Key words: β-carotene digestion, blood concentration, deposition, steers
Heat or cold chronic stress affects organ weights and Hsp70 levels in chicken embryos
Authors: Givisiez P. E. N. , da Silva M. M. , Mazzi C. M. , Ferro M. I. T. , Ferro J. A. , Gonzales E. , Macari M.
Published: April 2011

This study was carried out with the objective of evaluating the effect of heat (38.8°C) or cold (35.8°C) stress on chicken embryo development and tissues Hsp70 levels, after the 13th day of incubation. Embryo weight (percent egg weight), organ weight (percent embryo weight) and Hsp70 levels (ng Hsp70 mg–1 total protein) in different tissues (liver, breast muscle, heart, lungs, brain and kidney) were studied at the end of incubation. Cold stress induced a lower embryo weight and lower kidney and lungs weights, whereas heart and liver were lighter in heat-stressed embryos. An interaction between temperature and age was obtained only for Hsp70 levels in kidney and heart. Cold-stressed embryos showed higher Hsp70 levels in the brain, lungs and liver; a decrease in brain and breast muscle Hsp70 levels was seen from the 19th to 20th days in control embryos. Hsp70 levels increased with age in kidneys of control embryos and in heart of heat- and cold-stressed embryos. In conclusion, this study showed that chicken embryo organ weights are affected by incubation temperature, and that Hsp70 expression is tissue dependent (higher levels being seen in the brain) being cold-stress more effective in increasing Hsp70 levels in most studied tissues. Key words: Chicken embryo, development, Hsp70, incubation temperature
Quantification of energy expenditures of the gastrointestinal tract of steers fed three diets at two levels of intake
Authors: Kelly J. M. , Mutsvangwa T. , Milligan L. P. , Waldo D. R. , McBride B. W.
Published: April 2011

Forty eight yearling Holstein steers [257 ± 7.7 kg body weight (BW)] were fed switchgrass hay plus 10% soybean meal (diet S), orchard grass silage (diet O) and alfalfa silage (diet A) at 65 or 90 g DM kg–0.75 BW for 155 to 164 d in a 2 × 3 factorial experiment designed to evaluate the effects of dietary composition and level of feed intake on patterns of O2 consumption in gastrointestinal tract (GIT) tissues. At the end of the growth period, steers were stunned, exsanguinated and eviscerated. The various GIT components were then emptied of their contents and weighed. Ventral sac rumen, jejunal and large intestinal tissue samples were quickly acquired and placed in oxygenated M199 media. Mucosa and muscularis weights of these tissues were determined along with their total O2(TO2), ouabain-sensitive O2 (OSO2) and ouabain-insensitive O2 (OIO2) consumption. Oxygen consumption parameters were determined polarographically using a YSI Clark-style electrode. Total weights of rumen (P < 0.001), small intestine (P < 0.001) and large intestine (P < 0.05) were higher in steers fed the high level of intake compared to those fed the low level of feed intake. In all GIT tissues studied, increasing the level of feed intake (P <0.05) elevated mucosa and muscularis dry weights. Steers fed diet S had lower (P < 0.05) GIT tissue weights compared to those fed diets O and A. Weight-specific (i.e., expressed per unit tissue weight) TO2, OSO2 and OIO2 consumption for rumen, small intestine and large intestine were not affected by dietary composition and level of feed intake (P > 0.05), except for OSO2 consumption, which was higher (P < 0.05) in ruminal mucosa of steers fed diets S and A compared to those fed diet O. It is concluded that level of feed intake and dietary composition altered GIT O2 consumption via changes in visceral organ mass, rather than changes in weight-specific O2 consumption. Key words: Na+, K+-ATPase, gastrointestinal tract, Holstein steers
Effect of subacute ruminal acidosis on the preference of cows for pellets containing sodium bicarbonate
Authors: Cumby J. L. , Plaizier J. C. , Kyriazakis I. , McBride B. W.
Published: April 2011

Lactating cows with low rumen pH were given a choice between two test pellets during a 3-wk experiment. Intake of test pellets containing 4% sodium bicarbonate increased over time, but intake of control test pellets with an equal sodium content through inclusion of sodium chloride remained unaltered. Cows could have preferred bicarbonate pellets in order to attenuate ruminal acidosis, but increased aversion to sodium chloride cannot be excluded. Key words: Acidosis, diet choice, dairy cattle, sodium bicarbonate
Relationship of plasma leptin concentration to intramuscular fat content in beef from crossbred Wagyu cattle
Authors: Wegner J. , Huff P. , Xie C. P. , Schneider F. , Teuscher F. , Mir P. S. , Mir Z. , Kazala E. C. , Weselake R. J. , Ender K.
Published: April 2011

Plasma leptin concentrations and beef cattle carcass characteristics in eight Continental Crossbred steers [0% Wagyu Cattle (WC)] were compared to crossbred cattle with 50 and 75% WC (eight steers each) genetic makeup to determine if a relationship exists between plasma leptin concentrations and intramuscular fat content (marbling) in beef cattle. Plasma leptin concentrations were measured at two stages of cattle growth, 16 and 4 wk prior to slaughter (W P S). Beef cattle characteristics including marbling score, ribeye area, i.m. total lipid content, and backfat depth were determined, and correlation coefficients obtained between these traits and leptin concentration at both sampling dates. Plasma leptin concentrations increased relative to the lipid content in the 24 steers based on the significant positive correlation observed between plasma leptin and total lipids (% wet weight) from both pars costalis diaphragmatis (p.c.d.)(16 WPS: r = 0.69, P = 0.0004; 4 WPS: r = 0.35, P = 0.104) and longissimus (16 WPS: r = 0.59, P = 0.002; 4 WPS: r = 0.51, P = 0.011) muscles. A trend was observed, however, at 4 WPS when the groups of varying Wagyu genetics were compared. Plasma leptin was positively correlated with muscle lipid content for the 0% Wagyu cattle (longissimus: r = 0.62, P = 0.103; p.c.d.:r = 0.40, P = 0.410)but there was almost no correlation in these parameters for the 50% WC (longissimus: r = 0.11, P = 0.797; p.c.d.: r = 0.005, P = 0.990). Plasma leptin concentration was negatively correlated with lipid content in the 75% WC (longissimus: r = –0.60, P = 0.120; p.c.d.: r = –0.65, P = 0.164). The results suggest that increasing Wagyu genetics negates any relationship between leptin concentrations and i.m. fat content in cattle. Key words: Wagyu crossbred cattle, meat quality, intramuscular fat, marbling, leptin
Transfer of omega-3 linolenic acid and linoleic acid to milk fat from flaxseed or Linola protected with formaldehyde
Authors: Goodridge J. , Ingalls J. R. , Crow G. H.
Published: April 2011

Four Holstein cows were randomly assigned to four treatments in a 4 × 4 Latin square design. The primary objective of this study was to measure the transfer and increased level of omega-3 fatty acid C18:3 in milk by feeding sup plemental protected fat from flax and, second, to measure the transfer and increase in level of C18:2 by feeding supplemental protected fat from linola. The four dietary treatments were total mixed rations (TMR) plus i) control-no added fat, ii) high levels of protected Linola containing high linoleic acid content, iii) low level of protected flax containing high linoleic acid content and iv) high levels of protected flax containing high linolenic acid content. Linola is a variety of Solin containing approximately 74% linoleic acid, which was developed from flax. These supplements were added to the diet as a top dress and provided 454 g fat (high level) from the protected Linola product, 187 g fat (low level) from the protected flax product and 410 g fat (high level) from the protected flax product. Treatments had no effect on feed intake, milk yield or milk content of fat, protein or solids not fat. Medium chain fatty acids, C12:0 to C16:0, were significantly lower (P < 0.05) in the milk of cows fed supplemental fat. Milk stearic acid (C18:0) was significantly greater in the milk fat from cows fed Linola vs. control, but was unaffected by other dietary treatments. Milk linoleic acid (C18:2) was significantly higher at 10.3% in the milk of cows fed the protected Linola vs. the control at 4.8%. Linolenic acid (C18:3) was not affected by feeding Linola, but was significantly greater in the milk of cows fed the high level of protected flax (6.4% vs. 0.8% in the control). This represents an eightfold increase, while the low level of protected flax diet increased C18:3 by 3.9-fold in milk fat. Supplementing dairy cow diets with a formaldehyde-treated flax product at acceptable levels of fat for high producing cows results in a milk fat high in omega-3-linolenic acid. Key words: Flaxseed, cow, milk, fatty acids, linoleic acid, linolenic acid
Effects of heated drinking water on the production responses of lactating Holstein and Jersey cows
Authors: Osborne V. R. , Hacker R. R. , McBride B. W.
Published: April 2011

An experiment was conducted to evaluate the effect of heating the drinking water of lactating dairy cows in different ambient environments on the feed and water intake and milk yield and composition and hydration status of Jersey and Holstein cows. Eighteen cows were randomly assigned to either an ambient (7–15°C), or a continuously heated (30–33°C), drinking water treatment in a switchback design. The experiment was replicated four times [spring (24.4°C), summer (21.1°C), autumn (11.8°C), and winter (12.6°C)] in a tie-stall facility. Free water intake was 3.40–5.95% greater (P < 0.05) each time the heated versus ambient drinking water was supplied across all trials. Both breeds responded similarly. Feed intake was increased 4.47% (P < 0.001) when cattle were offered the heated water during the summer experiment. Milk yield was greater (P < 0.01) for the spring and summer (P < 0.05) experiments when cattle were consuming the ambient water treatment. Water treatment had no effect on milk components or hydration status. Cows consumed 40% of their daily water intake within 2 h of each milking and feeding time. The results of this experiment demonstrate that cows drank more warm water when offered, but the increase in free water intake did not influence milk yield. Key words: Drinking water temperature, milk yield, feed and water intake, dairy cattle
Growth performance, carcass quality, meat quality and fatty acid composition of pigs fed diets
Authors: Van Lunen T. A. , Hurnik D. , Jebelian V.
Published: April 2011

Two hundred gilts and 200 barrows, housed within sex in pens of 25, were randomly allotted to two replications of four dietary treatments to determine the effects of incorporating 30, 20, 10 or 0% extruded soybeans (ESB), displacing a commercial protein supplement, in barley-based grower and finisher diets for pigs. Growth, feed intake and carcass quality of the pigs, and meat quality and fatty acid composition of the pork from a random subset of the pigs on test were determined. No sex × diet interactions were observed. ESB inclusion rate had no effect on growth rate; however, per-pen feed consumption decreased numerically with increasing ESB resulting in an improvement in feed efficiency. The 30% ESB inclusion rate increased carcass fat content (P < 0.05) compared with the control, whereas lean content was unaffected. Meat colour and marbling score were similar across all treatments whereas fat and lean firmness was reduced by the 30% ESB inclusion rate (P < 0.05) compared with all other treatments. Increasing ESB in the diet altered the fatty acid content of the pork by decreasing the amount of short-chain saturated and monounsaturated fatty acids and increasing the amount of long-chain polyunsaturated fatty acids (PUFA). The results of this study indicate that ESB can be used as the sole source of supplemental protein in barley-based diets for pigs with no detrimental effects on performance and minimal negative effects on carcass and meat quality. Alteration of fatty acid content of pork from feeding ESB has both positive and negative implications for consumer acceptance by increasing PUFA content while concomitantly increasing the risk of premature oxidation. Key words: Extruded soybeans, pigs, pork, growth, fatty acids, meat quality