bluuebunny/crossref_metadata_2025 huggingface dataset:
Parenteral infections of coots, Fulica americana (Gm.), with Cyclocoelum mutabile (Zeder, 1800) and Cyclocoelum oculeum (Kossack, 1911) (Cyclocoelidae)
Authors: McLaughlin J. Daniel
Published: December 2009

Newly excysted Cyclocoelum mutabile and Cyclocoelum oculeum were injected into coots, Fulica americana. Six of the eight coots injected intraperitoneally with C. mutabile became infected. Two coots, necropsied 6 days postinfection (pi), had young C. mutabile in the liver. Four of the remaining six coots necropsied 45 days pi had adult C. mutabile in the air sacs, and all infected coots exhibited evidence of fluke migration in the liver. Five of 10 coots injected intraperitoneally with C. oculeum became infected. Two of four coots necropsied 6 days pi were infected and young C. oculeum were recovered from the body cavity. Three of the remaining six coots were found to be infected at necropsy 45 days pi and specimens of C. oculeum were recovered from the air sacs and nasal sinuses. Three of six coots receiving newly excysted C. oculeum injected directly into the interclavicular air sac harboured flukes in the air sac, trachea, and nasal sinuses at necropsy 45 days pi. In both experiments involving C. oculeum, specimens recovered from the nasal sinus were gravid, or nearly so, whereas those found in the air sacs and trachea were smaller and less mature. No evidence of liver migration in either experiment involving C. oculeum was observed.
The relationship between simulated seasonal temperatures and depth distributions in the freshwater pulmonate, Lymnaea stagnalis
Authors: Boag D. A. , Bentz J. A.
Published: December 2009

Fall-collected specimens of Lymnaea stagnalis were placed in aerated aquaria and held under constant light inside a controlled environment chamber that was subjected to an artificial temperature cycle between 19 and 2 °C. At water temperatures between 19 and 9 °C there was no evidence that these snails sought out either specific water depths or substrata on which to cling, nor that they moved at different rates. However, at water temperatures below 9 °C, they moved to deeper water, being significantly concentrated in the deepest water at temperatures below 4 °C. They also moved less, becoming essentially immobile at 2 °C, and spent more time clinging to solid substrata and avoiding the loose bottom sediments at these lower temperatures. No snail was recorded burrowing, even at the lowest temperatures.
Antibody production in cattle infected with Hypoderma spp.
Authors: Robertson R. H.
Published: December 2009

Antibody production in six groups of cattle artificially infected with both Hypoderma lineatum (de Vill.) and H. bovis (L.) and one group infected with only H. lineatum was followed using the tanned-cell hemagglutination technique with an extract of first-instar larvae of H. lineatam as antigen. The rate of antibody production in different age groups of cattle undergoing their first infection was similar. Cattle undergoing a second or subsequent infection had titers at the beginning of infection or exhibited anamnestic responses. The maximum mean titers for the groups occurred 260–295 days from infection. The yearlings had significantly higher mean maximum titers than calves, or 2- or 3-year-old cattle.
Sensory orientation in Notophthalmus v. viridescens (Amphibia: Salamandridae)
Authors: Hershey James L. , Forester Don C.
Published: December 2009

Adult red-spotted newts, Notophthalmus v. viridescens, were collected from an aquatic habitat and released on land in an arena 20 m from the shore of their home pond. Freshly captured, untreated newts exhibited significant orientation toward the pond. Positive orientation was also observed when solar cues and pondside landmarks were hidden and when animals were released at night. Pondward orientation persisted in eyeless newts and in newts with the pineal organ covered. Eyeless newts with covered pineals failed to orient toward the pond, although they did exhibit directional orientation. Anosmic newts exhibited random orientation. All sham-operated control groups oriented in the direction of the pond.Olfaction is implicated as the sensory mechanism most essential to home pond orientation. Photoreception is of secondary importance, apparently acting in conjunction with olfaction to refine the directional accuracy.
Structural correlates of tarsal and metatarsal functioning in Iguana (Lacertilia; Iguanidae) and other lizards
Authors: Brinkman Donald
Published: December 2009

In lizards, the metatarsus is laterally directed at the time of pedal plantarflexion. During pedal plantarflexion, the metatarsus undergoes an initial rotation around its long axis followed by an extension of the ankle joint. The mesotarsal joint guides the metatarsus during the transition from rotation of the metatarsus to extension of the ankle joint. The proportions of the metatarsus are related to the lateral orientation of the metatarsus. The fifth metatarsal functions as a lever in two different ways during pedal plantarflexion: during rotation of the metatarsus, it increases the leverage of the pedal flexors by placing the line of action of these muscles lateral to the mesotarsal joint; during extension of the ankle joint it increases the leverage of the pedal flexors by placing their line of action ventral to the intratarsal joint. The transverse metatarsal arch acts as a counterbend during rotation of the metatarsus. Movement at the fifth metatarsal – fourth distal tarsal joint does not contribute to movement of the fifth digit during grasping, although the fifth metatarsal plays a passive role in grasping by acting as a pulley around which certain tendons pass.
Some helminth parasites from the small intestine of free-ranging muskoxen Ovibos moschatus (Zimmermann) of Devon and Ellesmere Islands, Northwest Territories
Authors: Webster W. A. , Rowell J.
Published: December 2009

Intestinal contents from two muskoxen, Ovibos moschatus (Zimmermann), collected in March 1978 on Devon Island, N.W.T., both contained Marshallagia marshalli (Ransom 1906) and Nematodirus helvetianus May 1920. Intestinal contents from five muskoxen collected in August 1978 on Ellesmere Island, N.W. T., contained Moniezia expansa (Rudolphi 1810) (one of the five), Ostertagia trifurcata Ransom 1907 (one of five), M. marshalli (one of five) and N. helvetianus (two of five). Cysticerci of Taenia hydatigena Pallas 1766 were found in two of the five animals from Ellesmere Island.
Visual fields of the compound eyes of four species of Cicindelidae (Coleoptera)
Authors: Kuster J. E. , Evans W. G.
Published: December 2009

Visual field angles were measured around the circumference of the compound eyes of four species of North American Cicindelidae and plotted on Mollweide homolographs. Areas of monoscopic and stereoscopic visual fields and blind areas were calculated. In contrast to the nocturnal species (Amblycheila schwarzi and Omus californicus), the crepuscular species (Megacephala Carolina) and the diurnal species (Cicindela tranquebarica) have more ommatidia and larger eye size: head size ratios, total visual fields, and stereoscopic visual fields. These characters are considered to be derived and confirm the phylogenetic sequence of the four genera that was previously based on other morphological characters. The relationship between these characters and the biology of each species is also discussed.
Impact of marsh wrens on reproductive strategy of red-winged blackbirds
Authors: Picman Jaroslav
Published: December 2009

Marsh wrens destroy redwing eggs and young and are a major cause of redwing nesting mortality in a brackish water marsh in Delta, B.C. Redwing nesting success increases with distance of redwing nests from marsh wren nests. In spite of higher wren nest densities in 1977, wrens had a relatively smaller impact on redwing nesting success in 1977 than in 1976, when wren nest densities were lower.Interference between redwings and marsh wrens has apparently evolved to reduce competition between these species through the spatial segregation of their nesting sites. As a consequence of different efficiencies of their interference mechanisms in vegetation of various densities, marsh wrens appear to be more successful in dense cattail whereas redwings are the more successful species in sparser vegetation.Marsh wrens have an important effect on redwing reproductive strategy. Contagious nesting by redwing females significantly reduces impact of wrens. Individuals failing to adopt this strategy have a negligible chance of reproductive success. The hypothesis is proposed that marsh wrens may have influenced the evolution of a clumped pattern of nesting by redwings.
Haematozoa from resident and anadromous fishes of the central Columbia River: a survey
Authors: Becker C. Dale
Published: December 2009

Fish were surveyed for haematozoa from the central Columbia River, state of Washington, U.S.A., from 1968 to 1978. The 840 individuals examined represented 12 families and 34 species. Most infections occurred in sucker (Catostomidae) and sculpin (Cottidae). Nine species of fish were parasitized by one or two species of haematozoa. Intensities of all detected parasitemias were low, indicating no symptomatic damage to infected hosts.Trypanoplasma salmositica (Katz 1951) was recorded for the first time in white sturgeon (Acipenser transmontanus), largescale sucker (Catostomus macrocheilus), bridgelip sucker (C. columbianus), northern squawfish (Ptychocheilus oregonensis), and sculpin of the Cottus confusus/bairdi complex; it was also found again in prickly (C. asper) and piute (C. beldingi) sculpin. Haemogregarina catostomi Becker 1962 occurred in about 23% each of largescale and bridgelip sucker. Other haematozoa encountered were a haemogregarine in 1 of 23 steelhead (Salmo gairdneri), a haemogregarine in 3 of 92 sculpin (Cottus spp.), and a dactylosome in 1 of 10 American shad (Alosa sapidissima).The sequence of Haemogregarina catostomi occurrence in erythrocytes was the following: young gametocytes in the fall, mature gametocytes in winter, degenerative gametocytes in spring, and absence of infection in summer. The piscicolid leeches Myzobdella lugubris Leidy and Piscicola salmositica Meyer might transmit haematozoa among fish in the survey area.
Development, survival, and structural alterations of embryos and alevins of Atlantic salmon, Salmo salar L., continuously exposed to alkaline levels of pH, from fertilization
Authors: Daye P. G. , Garside E. T.
Published: December 2009

Embryos of the Atlantic salmon, Salmo salar L., were incubated continuously from fertilization at pH 6.8 (control) and pH 9.0 and 9.5, initially at 6.7 °C but with a gradual decline in the first 5 weeks to 5.0 °C for the remaining 10 weeks of exposure. Subsequently, the alevins were maintained in these environments for 50 days after hatching. Developmental processes and hatching were not affected by these levels of pH. Percentage cumulative mortality of treated embryos, 8%, was approximately that in the controls. Alevin mortality in the control lots was 1.2 and 1.3%. At pH 9.0, cumulative mortality was 0.4%, but at pH 9.5 there was an accelerating increase to 18%, at the termination of observation.Sublethal changes in embryos were confined mostly to cell necrosis and sloughed rudimentary epidermis. Some metaplasia of the brain stem occurred at pH 9.5. Sites and intensity of alterations increased in alevins at pH 9.5, following the loss of the zona radiata. In addition to ongoing injury of epidermis, including mucous cells, deleterious alterations occurred in branchial epithelium, erythrocytes, myocardium, blood vessels of the viscera, liver, brain, and optic lenses. In general, sublethal changes caused by hydroxylions are similar to those caused by excessive hydrogen ions but are somewhat less extensive in the structures affected or in their degree of severity.
Host-induced variations in Haematoloechus buttensis (Trematoda: Haematoloechidae)
Authors: Kennedy Murray J.
Published: December 2009

The life cycle of Haematoloechus buttensis was maintained in the laboratory by using the usual natural hosts: Rana pretiosa, Physa nuttalli, and Ischnura perparva. Morphological variations in important taxonomic characters were studied and compared with those found when one of the usual hosts was replaced by a sympatric, but usually uninfected, host. In all, six species of Amphibia, three of Insecta, and three Mollusca were used.The effect of host size, sex, and ambient temperature was also studied using R. pretiosa as definitive host.The most reliable taxonomic characters were determined to be the sucker ratio, egg size of 21-day-old and older worms, position of the testes, and the anterior extent of the extracaecal uterine loops.The unreliability of other characters and their prior use as species-specific features suggests that many of the currently recognized species of Haematoloechus are not valid.
Trypanosoma ambystomae in Ambystoma spp. (order Caudata) in southern Ontario
Authors: Woo Patrick T. K. , Bogart James P. , Servage David L.
Published: December 2009

Using the haematocrit centrifuge technique, Trypanosoma ambystomae was recorded from Ambystoma jeffersonianum, Ambystoma platineum, Ambystoma laterale, Ambystoma maculatum, and Ambystoma tremblayi from five areas in southern Ontario. The percentage of infected animals varied from about 5% in A. tremblayi to 27% in A. platineum and A. maculatum. This report not only expands the host range for the trypanosome, it is also the first report of it being found outside western North America. The division process of the trypanosome in the salamander is described and it is shown that it can be maintained in salamanders in the laboratory by blood inoculation.
Scent marking in coyotes
Authors: Bowen W. Don , Cowan Ian McTaggart
Published: December 2009

The scent marking behaviour of coyotes, Canis latrans, was studied in Jasper National Park, Alberta, during the period 1974–1976. Results show that adult males and females scent mark throughout their territory at all times of the year. Urine is most frequently used in marking. The rate of scent marking at the edge of the territory is approximately twice that in the center. This increase is accomplished by reducing the distance between scent-mark sites and increasing the proportion of multiple marks. All members contribute to the marking behaviour of the pack, although the dominant male marks most frequently. The scent marks of neighbours at territory borders are not avoided but vigourously marked. Nevertheless, it appears that marking is associated with the maintenance of territory.
Uric acid in the stratum argenteum of toadfishes Opsanus
Authors: Nicol J. A. C.
Published: December 2009

The outer chorioid (suprachorioid) of the eye of the toadfish Opsanus is a yellow argenteum which consists of two thin sheets. The inner one contains thin flat crystals of uric acid. The uric acid content is about 40 μg/cm2 of chorioid surface. The outer sheet contains yellow, birefringent granules, as yet uncharacterized. In conjunction with certain features of the retina, the yellow chorioid is responsible for eyeshine in the photopic eye.
Preliminary observations on escape swimming and giant neurons in Aglantha digitale (Hydromedusae: Trachylina)
Authors: Donaldson S. , Mackie G. O. , Roberts A.
Published: December 2009

Aglantha can swim in two ways, one of which, fast swimming, is evoked by contact with predators and serves for escape. The response consists of two or three violent contractions of which the first propels the animal a distance equivalent to five body lengths. Peak velocities in the range 0.3–0.4 m s−1 were measured. Drag is reduced by contraction of the tentacles.Coordination of escape swimming and tentacle contraction is achieved by a system of giant axons. A giant axon runs down each tentacle; action potentials in these elements show a one-for-one correspondence with potentials recorded from a ring-shaped axon lying in the margin near the tentacle bases. The ring giant synapses with eight motor giants which run up the subumbrella innervating the swimming muscles.Conduction velocities in the giant axons may be as high as 4.0 m s−1 in the case of the largest (40 μm diameter) axons. A value of 1.6 ms was obtained for minimum synaptic delay between the ring and motor giant axons.
Diets of juvenile coho salmon (Oncorhynchus kisutch) and steelhead trout (Salmo gairdneri) relative to prey availability
Authors: Johnson James H. , Ringler Neil H.
Published: December 2009

Monthly diets of juvenile coho salmon and steelhead trout and the composition of the bottom and drift fauna were examined in a tributary of Lake Ontario. From June through September coho fed most heavily on terrestrial invertebrates, whereas steelhead fed primarily on benthic invertebrates. Diet overlap (Ĉλ) between coho and steelhead was not significant. The diet of coho was closely associated with the composition of the drift; the diet of steelhead was more closely associated with the bottom fauna. Food selection may be influenced by observed differences in distribution (riffle versus pool) of sympatric steelhead and coho salmon, but mode of feeding (surface versus bottom) may also play a role. Because of the close relationship between drift composition and diet in coho, we hypothesize that diel variation in diet will be greater in coho than in steelhead.
Effects of crowding on the energetics of the barnacle Balanus glandula Darwin
Authors: Wu R. S. S.
Published: December 2009

Five experimental populations of the barnacle Balanus glandula Darwin, differing in their degree of crowding, were established on settling plates. Energy budgets were constructed and compared for individuals from each of the five populations. The results showed that crowding significantly reduced the energy consumption, assimilation, and production of body tissue, eggs, and shell of individual barnacles. The energy standing crop of the various body components was also reduced by crowding. Among these parameters, production of eggs appeared to be most sensitive to crowding. However, energy consumption, energy flow, and production of body tissue, eggs, and shell per unit area were all much higher in the crowded population, and the same pattern was observed for the energy standing crops of the various body components.
Zinc- and copper-binding proteins in the plasma of winter flounder (Pseudopleuronectes americanus)
Authors: Fletcher P. E. , Fletcher G. L.
Published: December 2009

Zinc- and copper-binding proteins were isolated from the plasma of winter flounder using gel filtration chromatography. A single copper-binding protein fraction of molecular weight 170 000 was isolated from the plasma of both sexes.In male and female flounder over 95% of the plasma zinc was associated with a zinc-binding protein(s) with a molecular weight of 76 000. In male flounder the remaining zinc appeared to be bound to a protein(s) of molecular weight 186 000. In female flounder the remaining 5% of the zinc was associated with two zinc-binding fractions with apparent molecular weights of 186 000 and 340 000 – 370 000.Extracts of plasma vitellogenin and egg yolk proteins revealed significant quantities of zinc and copper. It is hypothesized that the female specific zinc-binding protein (340 000 – 370 000) was vitellogenin.
Breeding characteristics of Townsend's vole (Microtus townsendii) during population fluctuations
Authors: Beacham Terry D.
Published: December 2009

A 2-year livetrapping study on Townsend's vole (Microtus townsendii) on Reifel Island in the Fraser River delta in British Columbia, Canada, showed that there was an early stop to summer breeding in the peak phase summer compared with the increasing phase summer. Selective dispersal and death of early-maturing voles may account for this result. A delay occurred in the onset of breeding in the decline phase. Voles in peak density populations had the highest median weights at sexual maturity, and males matured at heavier weights than did females.
Deformities in Capniidae (Plecoptera) from the Bow River, Alberta
Authors: Donald D. B.
Published: December 2009

Deformities occurred on the antenna, maxilla, labium, and cercus of two species of Plecoptera, Isocapnia integra Hanson and Utacapnia Columbiana (Claassen), from the Bow River in Alberta. The highest incidence of aberrant appendages occurred at sites downstream from domestic and industrial sewage outfalls. Deformities were absent or not frequent in these species at pristine sites. Domestic and industrial pollutants are implicated as the cause of these deformities.
The migration of humpback whales past the Bay de Verde Peninsula, Newfoundland, during June and July, 1978
Authors: Whitehead Hal , Harcourt Patricia , Ingham Kathleen , Clark Hannah
Published: December 2009

Approximately 255 humpback whales, Megaptera novaeangliae, moved through the waters off the Bay de Verde Peninsula, Newfoundland, between 1 June and 10 August 1978. Their distribution and northward migration speed were closely related to the density of depth sounder traces in the 80–120 m depth range, believed to have been made by postspawning schools of the humpbacks' major local prey, the capelin, Mallotus villosus. Residence times of individual humpbacks were usually less than 3 days. Only one animal had a preferred range within the study area.
Observations on the aggregation of adult cicadas (Homoptera: Cicadidae) in tropical forests
Authors: Young Allen M.
Published: December 2009

The distribution of adult cicadas in various tree species was studied in Costa Rica. These observations indicate that tropical cicadas, mostly males, often congregate in certain tree species in various kinds of secondary forest habitats. Aggregated male cicadas exhibit intense chorusing and females fly into chorusing aggregations, presumably for mating. Trees used for aggregations are also cicada feeding sites. The conspicuous absence of oviposition evidence or nymphal skins suggest that these trees are used primarily for intensive male chorusing which assembles females for mating. Tendency to congregate in particular trees is related to the spatial position of the trees and their exposure to direct sunlight. Highly fragmented forest patches in some regions (central highlands, lowland Guanacaste) function as islands for cicadas to complete their life cycles and mating, whereas the abundant secondary forest habitats in other regions (northeastern lowlands) are being invaded by a few species which use secondary forest trees for completion of life cycles and mating. The apparent absence of dense aggregations of adult cicadas within climax tropical forests, even though nymphal skins are found here, is probably related to the very patchy distribution of individuals of each tree species and perhaps other factors (i.e., shading) affecting the attractiveness of trees for congregating cicadas.
Homing behavior and orientation in the red-backed vole, Clethrionomys gapperi
Authors: Bovet Jacques
Published: December 2009

Red-backed voles (Clethrionomys gapperi) were displaced and released 200, 400, or 600 m from their home sites. Data collected on behavior of displaced voles in the release site area indicate that some individuals remained there for days or weeks after release while others left within 32 h. Although homing success was inversely related to displacement distance, the proportion of displaced voles that remained in the release site area was unrelated to displacement distance and voles that left did so predominantly in the home direction ± 90°, irrespective of eventual actual homing or lack thereof and independently of the distance from the home site. These results are in better agreement with predictions of a model that implies a navigational mechanism as a basis of homing ability than with those of a model that implies random dispersion or recognition of known landmarks in the release site area.
Blood parasites of fish from the northwestern Atlantic Ocean
Authors: Khan R. A. , Barrett M. , Murphy J.
Published: December 2009

Examination of thick and thin blood smears from 5013 marine fish from the northwestern Atlantic Ocean revealed 25 of 59 species to be infected with one or more of the following blood parasites: trypanosomes (27% of 3610), trypanoplasms (9% of 588), piroplasms (26% of 2584), and haemogregarines (36% of 1708). Higher prevalences of infection were observed in cold-water, benthic, sedentary fish than in warm-water, littoral, epipelagic, or midwater species. Trypanosome infections were more prevalent among fish taken off the Labrador – east Newfoundland coasts, lower in those from St. Pierre Bank, Grand Bank, and Gulf of St. Lawrence, and lowest in forms from the Scotian Shelf. Seven of nine species of hematophagous leeches harboured asexual stages of haemogregarines, whereas natural infections of trypanosomes occurred in one leech, Johanssonia arctica. Using five species of laboratory-reared leeches and laboratory-initiated infections of trypanosomes in piscine hosts, development of Trypanosoma murmanensis was observed only in J. arctica. It is suggested that the distribution of trypanosomes of marine fish is related to that of J. arctica, a cold-water species, whereas the other haematozoan infections might be attributed to those leech species that are associated with their respective piscine hosts.
Morphology and innervation of mouthpart sensilla in larvae of the spruce budworm, Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae)
Authors: Albert P. J.
Published: December 2009

The structure and innervation as determined by methylene blue techniques of the sensilla of the maxillary palp, galea, mandible, labrum, and labial palp of the spruce budworm larva are described, based on light and scanning electron microscopy. An attempt is made to identify the function of various sensilla by comparing them with those of other insects. The function of the gustatory sensilla on the galea and epipharynx is confirmed electrophysiologically.
Host specificity among the helminth parasites of four species of snakes
Authors: Rau Manfred E. , Gordon David M.
Published: December 2009

The helminth parasites of 141 snakes were collected. The nematode Rhabdias fuscovenosa was found in all snake species except Nerodia sipedon, whereas Cosmocercoides dukae was restricted to Storeria dekayi. The trematodes Zeugorchis aequatus and Lechriorchis primus occurred only in Thamnophis sirtalis, whereas Dasymetra nicolli infected only N. sipedon. Pneumatophilus variabilis primarily parasitized N. sipedon but was occasionally found in T. sirtalis. Mesocercariae of Alaria sp. were found in all species except S. dekayi. The cestodes Ophiotaenia sp. and Cylindrotaenia sp. were found in N. sipedon and T. sirtalis, respectively.
Localization of chemoreceptors which may cause diving bradycardia in bullfrogs
Authors: Lillo Richard S.
Published: December 2009

The location of chemoreceptors causing diving bradycardia in bullfrogs, Rana catesbeiana, was investigated. Intravenous sodium cyanide injections (50–75 μg/kg) into unanesthetized frogs caused hyperventilation and an increase in arterial blood pressure. When frogs were submerged, such injections produced bradycardia and a fall in blood pressure.Injections of cyanide (25–50 μg/kg) into the right or left pulmocutaneous arch of lightly anesthetized frogs which were breathing acted as a respiratory stimulant; similar injections produced bradycardia when frogs were submerged. Injections of cyanide into the right or left carotid arch when frogs were breathing stimulated ventilatory movements. Injections into the carotid arch when frogs were submerged had no substantial effect on cardiac rate. No responses were noted after cyanide was introduced into the right or left systemic arch.These preliminary data suggest that there are respiratory chemoreceptive areas in bullfrogs which are stimulated by blood perfusing both the carotid and pulmocutaneous arches. Chemoreceptors located along the circulation of the pulmocutaneous arch may play a role in the bradycardia response during submergence in bullfrogs.
Nest insulation: a method of evaluation
Authors: Wrabetz Michael J.
Published: December 2009

Despite the demonstrated thermoregulatory effect of mouse nesting, its quantification has usually involved nonthermal measurements. A technique for measuring the thermal resistance of a nest is introduced, and problems with a previous system are discussed. Data are presented to show that thermal and nonthermal measurements of nesting may not be equivalent.
Eyeshine in fishes. A review of ocular reflectors
Authors: Best A. C. G. , Nicol J. A. C.
Published: December 2009

Eyeshine in fishes is reviewed. It originates in several ways. Many benthic fishes have pupils that are iridescent at certain angles of vie w; the color is caused by reflection of light at the surfaces of thin films in the cornea. Several kinds of cellular or extracellular features are involved. Reflection of light from the retinal surface is usually dull. In Photonectes there is bright reflection from part of the retinal surface; it comes from rows of thin cytoplasmic lamellae within Müller fiber cells. Many fishes have retinal tapeta lucida: these are diffuse reflectors made up of densely packed spherules, or specular reflectors made up of layers of thin films. Tapeta cellulosa in the inner chorioid also are specular reflectors containing thin films. Often, these tapeta can be covered over by migratory pigment in the photopic eye. Eyeshine in the light-adapted eye of several groups (scorpion fishes, etc.) comes from a reflex of light at the stratum argenteum. It is made possible because all the retinal pigment enters the cell processes, and there is no dark pigment in the chorioid.
Effects of salmon gonadotrophin (SG-G100) on plasma lipids in the goldfish, Carassius auratus
Authors: Wiegand Murray D. , Peter R. E.
Published: December 2009

Female goldfish were held under conditions of 12 °C and a 12 h light: 12 h dark photoperiod during three phases of the sexual cycle. A pretreatment blood sample was taken after 2 weeks of acclimation. Comparison of pretreatment levels of plasma lipids from the three experiments revealed that the concentration of triglycerides (TG) increased and total cholesterol (TC) decreased with increasing ovarian size. Plasma lipid phosphorus (LP) levels were slightly higher in sexually mature fish than in sexually regressed fish. Two weeks after the pretreatment blood sample, the fish were injected intraperitoneally with salmon gonadotrophin (SG-G100) or control solution for 3 days, after which a posttreatment blood sample was taken. In sexually maturing fish injection of SG-G100 caused increased plasma TG levels (compared with pretreatment) in fish with small ovaries, changing to decreased levels in fish with larger ovaries. A similar effect was also seen in maturing fish with plasma TC; these effects were abolished by castration or by keeping fish at 21 °C. SG-G100 had little effect on plasma LP. The results suggest that gonadotrophin causes a net mobilization of lipid in fish with small ovaries (presumably via sex steroids) and accelerated ovarian uptake of lipid in fish with larger ovaries.
The limnological factors associated with cytotypes of the Simulium (Simulium) venustum/verecundum complex (Diptera: Simuliidae) in New York state
Authors: Gordon A. Elizabeth , Cupp E. W.
Published: December 2009

A survey of cytotypes of the Simulium (Simulium) venustum/verecundum complex and of associated limnological conditions was conducted from April to October, 1978, in northern and western New York state. Water was analyzed for the following 21 factors at four sites: sodium, potassium, calcium, magnesium, chloride, sulfate, bicarbonate, nitrite, nitrate, total nitrogen, ammonium, orthophosphate (MRP), total phosphate (TSP), iron, aluminum, conductivity, silicate, dissolved oxygen, temperature, velocity, and pH.The common species and their distributions were the following: northern New York, ACD and AA-AC verecundum; western and northern New York, CC. The complex divided into two groups on the bases of pH, ionic content, and ratios of the water. Northern species occurred in mildly acidic, dilute, bicarbonate- and sulfate-dominated waters. Western species occurred in neutral, rich, bicarbonate-dominated water. Three phenological groups were found based on coldest temperature tolerated. These cytotypic differences were briefly related to the needs of a control program.
Factors controlling lambing period of Dall's sheep
Authors: Bunnell Fred L.
Published: December 2009

Distribution of birth dates within the study population of Ovis dalli dalli reveal two distinct oestrous cycles with a further 15% of all births resulting from a third cycle. The onset of breeding appears governed by photoperiod. Lambs born early and late in the lambing period suffer higher mortality. Energetic constraints limit both onset and duration of lambing. Onset is delayed beyond the period critical to thermoregulation by lambs and until forage is adequate; duration is limited by the need of lambs to attain adequate body size by winter.
Properties of Na, K-ATPase from the salivary glands of the ixodid tick Amblyomma hebraeum
Authors: Rutti B. , Schlunegger B. , Kaufman W. , Aeschlimann A.
Published: December 2009

Tick (Amblyomma hebraeum) salivary glands are a rich source of Na,K-ATPase (EC 3.6.1.3), the fundamental properties of which are similar to those of Na,K-ATPases from other sources. Inhibition of the enzyme by ouabain is quantitatively similar to the inhibition of fluid secretion by this drug. Harmaline at high concentrations also inhibited the Na,K-ATPase. The nucleotides GTP, ITP, and UTP were utilized as substrates, but all were less effective than ATP. Noradrenaline, dopamine, and phenoxybenzamine, all at concentrations known to influence fluid secretion in vitro, had no effect on enzyme activity.
Seasonal changes in thyroid activity in the lesser snow goose (Anser caerulescens caerulescens) including reference to embryonic thyroid activity
Authors: Campbell R. R. , Leatherland J. F.
Published: December 2009

Plasma thyroxine (T4) levels in adult lesser snow geese (Anser caerulescens caerulescens) increased concomitantly with gonadal recrudescence and remained elevated until shortly before moult. This pattern of declining plasma T4 concentrations preceding moult was evident in gosling, yearling, and adult birds. Plasma triiodothyronine (T3) concentrations did not change significantly throughout the year. There was no apparent correlation between plasma thyroid hormone levels and thyroid weight or thyroid epithelial cell height. Plasma levels of both T3 and T4 increased in goslings shortly before hatch and on day 20 of incubation reached levels (0.58 ± 0.36 and 19.5 ± 2.5 ng∙mL−1, respectively) similar to those found in the plasma of newly hatched birds (0.76 ± 0.24 and 36.0 ± 6.5, respectively).
The direct transmission of Andersonstrongylus captivensis Webster 1978 (Metastrongyloidea: Angiostrongylidae) in captive skunks Mephitis mephitis (Schreber)
Authors: Webster W. A.
Published: December 2009

Patent infections of Andersonstrongylus captivensis Webster 1978 were established in skunks by feeding infected lungs or gravid females removed from infected lungs. Feeding larvae recovered from infected faeces did not produce an infection. This is the third metastrongyloid for which a direct life cycle has been demonstrated. Possible methods of transmission could be by cannibalism, coprophagia, or at times of regurgitative feeding of young, although the latter has not been observed.
Host specificity and distribution of the swim-bladder nematodes, Cystidicola farionis Fischer, 1798 and C. cristivomeri White, 1941 (Habronematoidea), in salmonid fishes of Ontario
Authors: Lankester Murray W. , Smith John D.
Published: December 2009

Cystidicola farionis is reported in Coregonus clupeaformis, C. artedii, C. hoyi, C. nigripinnus (new host record), Prosopium cylindraceum, Oncorhynchus gorbuscha (new North American record), O. kisutch, O. tshawytscha (new host record), Salmo gairdneri, S. trutta, Salvelinus fontinalis, S. namaycush, S. namaycush × S. fontinalis, and Osmerus mordax. The last five fishes listed, however, are considered unsuitable hosts for C. farionis as few, if any, worms reached sexual maturity in these hosts. Coregonus clupeaformis is also unsuitable as a host for C. farionis in lakes Superior and Nipigon. The swim-bladder nematode that matures in lake whitefish in Lake Huron and some inland lakes in northwestern Ontario may be a new species.Factors that may affect the abundance of C. farionis in various fishes are examined and the relative importance of different amphipods as sources of infection is discussed.Cystidicola cristivomeri matures only in hosts of the genus Salvelinus, including S. namaycush and S. alpinus, and is reported here for the first time in S. fontinalis.Ulcerations in the wall of the swim-bladder were seen only in S. gairdneri infected with C. farionis and in S. namaycush infected with C. cristivomeri. The lesions apparently resulted when unusually large numbers of swim-bladder nematodes were present.
New marine species of Marionina and Enchytraeus (Oligochaeta, Enchytraeidae) from British Columbia
Authors: Coates Kathryn
Published: December 2009

Four new species of Marionina and one of Enchytraeus have been discovered during marine oligochaete surveys in British Columbia. Three new species of Marionina, M. vancouverensis, M. charlottensis, and M. neroutsensis, are similar to a group of other species including M. spicula (Leuckart, 1847), M. brevis Finogenova, 1977, M. istriae Giere, 1974, and M. sublittoralis Erséus, 1976. Marionina vancouverensis is estuarine; M. charlottensis is less estuarine and associated with upper intertidal algae such as Fucus and Enteromorpha; M. neroutsensis is also an upper intertidal form but from saturated fine sediments. In contrast, M. trevori has an unusual combination of generic characters separating it from other species of the genus. It was collected from coarse sand with decaying algae near a sewage outflow. Enchytraeus rupus is similar to several other small Enchytraeus species only a few of which have been found intertidally and none previously on the Pacific coast of North America.
Distribution and zoogeography of planktonic crustaceans and dipterans in glaciated eastern North America
Authors: Carter J. C. H. , Dadswell M. J. , Roff J. C. , Sprules W. G.
Published: December 2009

Zooplankton samples, usually together with morphometric, physical, and chemical data, were collected from 696 lakes in glaciated eastern North America between 1969 and 1978. Geographical distributions of the 44 Crustacea and 4 Diptera species suggest six broad categories: 23 species appear to have no barriers to dispersal throughout the area; 7 have restricted ranges, possibly because of either recent evolution or competitive exclusion; 3 may be gradually invading the area from centres to the south or west; 1 is a euryhaline estuarine form with a limited freshwater distribution; 4, possibly 5, are found almost exclusively in areas of former glacial lakes or spillways and may be classified as "glacial opportunists"; 9 species have distributions which appear to be linked in some unspecified way to calcium–magnesium water hardness.
Mechanical transmission of larval Trichinella by arctic crustacea
Authors: Hulebak Karen L.
Published: December 2009

This experiment was done to determine if transmission of Trichinella spiralis larvae could be accomplished through arctic marine invertebrates as mechanical hosts. Marine Crustacea (amphipods and shrimps) were trapped in the Chukchi Sea, held in aerated tanks of sea water, and fed on glycerin-preserved trichinous rat muscle. Following exposure, Crustacea were held for various periods, then cryopreserved for later examination in the laboratory. Larvae were found in the alimentary canals of seven crustacean species. Their ability to persist within such invertebrates for as long as 28 h lends support to the hypothesis that Crustacea might act as mechanical transmitters of Trichinella to fish and invertebrate-eating marine mammals.
Circadian activity of the white sucker, Catostomus commersoni: comparison of individual and shoaling fish
Authors: Kavaliers Martin
Published: December 2009

Individual and shoaling white suckers, Catostomus commersoni, displayed free running circadian rhythms of locomotor activity under conditions of constant darkness and temperature. The circadian activity of shoals was different from that of single fish. The activity of single fish was rhythmic initially with a period of less than 24 h, but became arrhythmic after 15–30 days. Shoals of white suckers had a less variable circadian period that was greater than 24 h, and showed no evidence of arrhythmicity. The circadian activity of shoals is determined by its behavioural and social organization; it is not simply a more precise version of the activity of single fish.
Water relations of pliable-shelled eggs of common snapping turtles (Chelydra serpentina)
Authors: Packard Gary C. , Taigen Theodore L. , Packard Mary J. , Boardman Thomas J.
Published: December 2009

Pliable-shelled eggs of common snapping turtles were incubated at 29 °C under hydric conditions simulating those to which eggs are exposed in natural nests. Eggs exposed to conditions similar to those encountered at the centre of nests experienced net declines in mass during incubation, presumably owing to the loss of water vapour to air trapped inside the chamber. Eggs exposed to conditions similar to those encountered at the periphery of nests absorbed liquid water across that part of their shell contacting the substrate and increased in mass during the early weeks of incubation. However, transpirational water loss from exposed surfaces of these eggs seemed to increase coincident with metabolism of developing embryos, and became high enough by the midpoint of incubation that absorption of liquid water could not compensate for the loss of water vapour, thereby causing eggs to decline in mass for the remainder of incubation. The size of hatchlings was related both to the position of eggs inside the chamber and to wetness of the substrate, indicating that the water exchanges of pliable-shelled eggs of snapping turtles may be of considerable importance to developing embryos.
The potential for using the anabolic hormones 17α-methyltestosterone and (or) 3,5,3′-triiodo-L-thyronine in the fresh water rearing of coho salmon (Oncorhynchus kisutch) and the effects on subsequent seawater performance
Authors: Fagerlund U. H. M. , Higgs David A. , McBride J. R. , Plotnikoff M. D. , Dosanjh B. S.
Published: December 2009

Juvenile coho salmon (Oncorhynchus kisutch) held in 11 °C fresh water (FW) were fed Oregon moist pellets supplemented with 3,5,3′-triiodo-L-thyronine at 4 ppm (T34) or 20 ppm(T320) and (or) 17α-methyltestosterone at 0.2 ppm (MT0.2) or 1 ppm (MT1) until early or normal seawater (SW) transfer.During FW residency all hormonal treatments improved growth, appetite, and food utilization. In February, fish fed T320 singly or with MT had increased degranulation of somatotrop cytoplasm. Thyroid epithelial cell height of fish fed T34 or T320 was either suppressed or enhanced. MT1 singly or combined with T3 induced androgenic side effects in males. Proximate body composition was affected only by MT. T320 induced morphological anomalies and treatment was discontinued. In May, thyroid activity and number of putative gonadotrops of fish fed MT1 were increased. Androgenic effects of all groups given MT1 were greater in May than in February.After SW transfer in February growth, appetite, and food utilization were depressed but fish fed T34 performed better than controls. Performance of all groups improved after May but, in general, mortality increased slightly. After transfer in May, T3-fed fish had increased growth in length.It is concluded that MT and T3 effectively enhance growth in FW but only T3 facilitates SW transfer.
Interspecific and intraspecific song discrimination by Zonotrichia albicollis and Z. leucophrys
Authors: Pleszczynska Wanda
Published: December 2009

White-throated sparrows (Zonotrichia albicollis) of both sexes and male white-crowned sparrows (Z. leucophrys) were studied in regard to their ability to discriminate songs of their North American congeneric species.Results show that intraspecific signals of all North American Zonotrichia sparrows share at least one common element and that they elicit interspecific responses. This similarity probably has its foundation in common ancestry, rather than in evolved interspecific communication. For white-throats, the total length of pure notes seems to carry the information for species recognition, whereas for white-crowns, a combination of pure notes with trills carries the highest intraspecific information.
Maternal influences on size and emergence time of the cinnabar moth
Authors: Richards Laura J. , Myers Judith H.
Published: December 2009

Maternal effects on egg weight, wing length, and emergence time were studied in the cinnabar moth. Egg weight was related to hatching success, but neither egg weight nor order of laying were related to pupal weight of larvae reared under greenhouse conditions. Heritabilities of wing length and emergence time calculated from the regression of mean offspring values on female parent were 0.30 ± 0.12 and 0.39 ± 0.14 respectively for female offspring. Regressions for male offspring were not significant. Significant differences between families in an ANOVA however were indicative of genetic variance. Genetic variance for female emergence time is discussed as one mechanism which has enabled synchronization of moth emergence with the appropriate phase of food plant phenology for larval development.
The morphology of cysts of Sarcocystis infecting birds in western Canada
Authors: Drouin T. E. , Mahrt J. L.
Published: December 2009

A light microscope study of the cyst wall of some avian Sarcocystis spp. was undertaken to determine if there were morphological differences in cysts found in different bird species. The cyst wall of macrocysts was different in young and old ducks. Five kinds of microcysts were described from birds, two having smooth outer walls, and three having radial spines on their outer surface. Cysts were differentiated on the basis of the thickness of the outer wall, and on the length and proximity of the radial spines to each other. Specific cyst types were found in several different bird species, and given bird species may harbor more than one cyst type, sometimes concurrently. It is hypothesized that the different cyst types represent different species of Sarcocystis.
Behavioral aspects of cannibalism in larval walleye, Stizostedion vitreum
Authors: Cuff Wilfred R.
Published: December 2009

Behavioral aspects of cannibalism in larval walleye (Stizostedion v. vitreum) are described. Conspecific prey were taken both head and tail first. Tail-first cannibalisms sometimes occurred wherein the cannibalized walleye was not ingested completely. This made it possible for a cannibal with partly-ingested prey to be cannibalized and "chains" of up to four fish were observed. As all larval walleye were roughly the same size, this observation suggests that larval walleye will take prey longer than themselves. This was also apparent from head-first encounters, with each fish trying to cannibalize the other.