bluuebunny/crossref_metadata_2025 huggingface dataset:
The ultrastructure of the epimastigote stages of Trypanosoma rotatorium in the leech Batracobdella picta
Authors: Desser Sherwin S.
Published: August 2008

Large numbers of epimastigotes were observed adjacent to the gastric epithelium of leeches (Batracobdella picta) that had fed 18 days earlier on a frog infected with Trypanosoma rotatorium. Electron microscopic study revealed that the modified flagellar sheaths of some of the epimastigotes formed hemidesmosomes with the gastric epithelium. Cytoplasmic components of the parasites included free ribosomes, sparse agranular reticulum, a well developed mitochondrial tube with plate-like cristae in the pre- and post-nuclear regions, two types of lipid inclusions, and two types of vesicular inclusions. The basal region of the typical flagellar apparatus was surrounded by an electron-dense, cylindrical sleeve situated immediately beneath the plasmalemma of the flagellar pocket. A polysaccharide component was demonstrated cytochemically on the outer surface of the plasma membrane of the epimastigotes.
The effect of various types of brood comb on the ovary development of worker honeybees
Authors: Jay S. C. , Jay Doreen H.
Published: August 2008

The effect of new comb, old brood comb, and no comb (when a queen and worker brood are present or absent) on the ovary development of worker bees in small colonies was examined. The presence of a queen and (or) mixed worker brood inhibited ovary development. No differences occurred in ovary development of workers in queenless, broodless hives when new comb, old brood comb, or no comb was present.
Influence of changing grouse density and forest attributes on the occupancy of a series of potential territories by male ruffed grouse
Authors: Boag D. A.
Published: August 2008

The history of occupancy of 117 territories established by male ruffed grouse (Bonasa umbellus) on a 700-ha study area in southwestern Alberta was studied over 11 years in relation to changing density of the grouse and attributes of the surrounding forest. The pattern of use of territories varied from continuous occupancy by a series of different birds over as many as 11 years to sporadic occupancy for as little as one season. These two extremes differed in that continuously occupied territories possessed numerous acceptable display sites, were located towards the center of clumps of territories, and hosted long-lived birds. By contrast, sporadically occupied territories possessed few acceptable display sites, tended to be located at the periphery of clumped territories, and hosted short-lived birds. Although the status of the vegetation around the display sites within the territory was a major factor influencing its occupancy, social interactions among the grouse also appeared to influence the history of its use.
Immediate response of the hemoglobin system of the goldfish, Carassius auratus, to temperature change
Authors: Houston A. H. , Rupert R.
Published: August 2008

Goldfish acclimated to 3 and 23 °C were characterized by two- and three-component hemoglobin systems, respectively. After acclimation to a diurnally cycling temperature regime (~3 to ~23 °C), specimens sampled at ~23 °C and ~3 °C were identical in terms of hemoglobin system complexity with those held at equivalent constant temperatures. Abrupt transfer of fish acclimated at constant 23 °C to 3 °C, and vice versa, lead to appearance or disappearance of the minor component, G.1, within 3 h. In vitro cooling and warming of whole blood and hemolyzate samples indicated that hemoglobin system modification occurred under cell-free as well as cell-intact conditions. These observations suggest that previously observed quantitative variations in the hemoglobin systems of thermally acclimated teleosts may represent, in part at least, altered aggregation of preexisting subunits rather than de novo hemoglobin synthesis and raise the possibility that teleostean hemoglobin systems may possess a capacity for rapid, adaptative reorganization after environmental temperature variation.
A contribution to the genus Diorchis Clerc (Cestoda: Hymenolepididae): a redescription of Diorchis americana Ransom, 1909 from Fulica americana (Gm.)
Authors: McLaughlin J. Daniel , Burt Michael D. B.
Published: August 2008

Diorchis americana Ransom, 1909 is redescribed from freshly collected material, and its relationship with Diorchis americana var. turkestanica Skrjabin, 1914 (Diorchis turkestanica Schultz, 1940) and Diorchis brevis Rybicka, 1957 is examined. D. americana differs from the other two species primarily in the structure of the copulatory portion of the vagina.
Winter foods of moose in La Vérendrye Park, Québec: an evaluation of two browse survey methods
Authors: Joyal Robert
Published: August 2008

The winter foods of moose (Alces alces) were determined in three winter yards in representative mixed forests of western Quebec. Browse use was measured by estimation of browse units and by twig counts. The first method enabled identification of key species in the diet while the second gave, in weight, the proportion of each. Both methods are compared. A total of 21 species offered available food, but only 12 were browsed. More than 75% of the diet in dry weight came from mountain maple (Acer spicatum), balsam fir (Abies balsamea), and willows (Salix spp.), with 53, 13, and 9.5% respectively. The mean weight of browsed twigs of different species varied. widely. Balsam fir twigs weighed about seven times more than white birch (Betula papyrifera) and 10 times more than beaked hazel twigs (Corylus cornuta). Moose preferred willows and trembling aspen (Populus tremuloides), which showed the highest availability:utilization ratio. Mountain maple was eaten proportionally to its availability. Results can be used in carrying-capacity studies in other mixed stands of eastern Canada.
Two new species of the genus Hemicypris Sars, 1903 (Ostracoda: Crustacea) from India
Authors: Victor Reginald , Fernando C. H.
Published: August 2008

Two new freshwater ostracod species of the genus Hemicypris Sars, 1903 are described from India and compared with related species.
Fine structure of the midventral abdominal tracheal glands in banded woolly bear caterpillars (Arctiidae: Lepidoptera)
Authors: Byers J. R. , Hinks C. F.
Published: August 2008

Caterpillars of Pyrrharctia isabella have four well developed tracheal glands located at the midventral anastomosis of the transverse tracheae in the third to sixth abdominal segments. The glands are approximately spherical, about 0.7 mm in diameter, and consist of a single, lobulated layer of very large glandular cells enclosing a sacculated reservoir. The haemal margin of the gland cells is characterized by extensive plasma membrane infoldings and the lumenal margin abutting the reservoir is deeply invaginated to form large microvilli-lined secretory cavities. The secretory cavities contain a lipoidal secretion that occurs in the form of fragmented plate micelles with a lamellar periodicity of about 55 Å. The secretory cavities are confluent with subcuticular spaces, from which the secretion can cross the lumenal cuticle into the reservoir and thence gain access to the exterior via the tracheal system. The most significant cytoplasmic features of the gland cells are an abundance of smooth endoplasmic reticulum and numerous small golgi complexes. Functional aspects of the cellular organization are discussed in relation to the possible role of the tracheal glands.
The life cycle of Trypanosoma murmanensis Nikitin
Authors: Khan R. A.
Published: August 2008

Trypanosoma murmanensis from the blood of the Atlantic cod, Gadus morhua, undergoes multiplicative development in the digestive tract of a marine leech Johanssonia sp. as the amastigote and sphaeromastigote stages. Epimastigotes, which apparently do not divide, migrate later to the proboscis of the leech and subsequently transform to metatrypomastigotes that are transmitted during engorgement. Fine granules of yellow pigment, observed in all stages, eventually disappear in the metatrypomastigotes. The cycle in the leech is completed in 62 days at 0–1 °C but is more rapid (42 days) at 4–6 °C. Cod-fed infected leeches remained aparasitemic. Trypomastigotes did not develop in two species of parasitic copepods, Lerneocera branchialis and Clavella adunca.Small, slender trypomastigotes, which appear from 3 days after infection, grow into larger forms that subsequently acquire myonemes. The average maximum size occurs about 55 days after infection. There is always a range of sizes, which becomes more apparent as the parasitemia declines from about 29 days. Parasitemias vary from 105 per millilitre to numbers too few to estimate accurately. No divisional forms were observed in cod and increased parasitemias do not apparently occur after inoculations of infected blood.
Factors affecting the reproductive success of common tern (Sterna hirundo) colonies on the lower Great Lakes during the summer of 1972
Authors: Morris Ralph D. , Hunter Rodger A. , McElman James F.
Published: August 2008

The breeding biology of five common tern (Sterna hirundo) colonies in the lower Great Lakes was studied between May and August 1972. Frequent visits were made to each colony and data collected on nests within large artificially enclosed areas. The objective was to identify factors that influence the reproductive success of common tern colonies on the Great Lakes. Hatching success was significantly dependent on clutch size and time of clutch initiation, whereas fledging success was independent of clutch size. The most common category of egg failure was disappearance from the nest. One colony (Port Colborne) realized a significantly higher hatching and fledging success than the others, among which there were no significant differences in prehatch or posthatch success rates. Factors that contributed to differences in reproductive success are presented and their relative contributions to the reproductive success of the tern colonies are discussed. The factors include the relative proportion of three-egg clutches, incubation time as a measure of 'parent attentiveness,' numerical size of the colony, predation, competition for nesting sites by gulls, food availability, flooding, and toxic chemicals. We conclude that no single factor can be readily correlated with reproductive success and suggest that caution should be exercised when considering the relationships between reproductive success and factors influencing it.
Ovenbird (Aves: Parulidae) hunting behavior in a patchy environment: an experimental study
Authors: Zach Reto , Falls J. Bruce
Published: August 2008

We investigated the foraging behavior of ovenbirds (Seiurus aurocapillus) in a patchy food supply. Nine birds were individually exposed on 2 successive days to four patches of 1.5 × 1.5 m containing 2, 4, 8, and 16 prey, respectively, in a 6 × 6 m field arena. Patch locations were kept constant; however, prey densities were interchanged on day 2.Amount of search path in patches increased exponentially with prey density. Birds rapidly shifted their search effort when prey densities were interchanged. Differential distribution of search effort resulted from more visits and greater search path per visit, owing to greater tortuosity of the search path in denser patches. Since less search path was required per prey found in denser patches, the search effort was concentrated in areas of high profitability and the birds took a higher percentage of prey available in these patches. However, in comparison with a simple model, their foraging among patches was suboptimal, except in the final period of day 1. Birds tended to avoid some recently visited patches although the overall sequence of visits to the four patches was random.It is proposed that differences in renewal and depletion rates of prey are important determinants of foraging behavior of ovenbirds and other species feeding in patchy environments.
Do ovenbirds (Aves: Parulidae) hunt by expectation?
Authors: Zach Reto , Falls J. Bruce
Published: August 2008

We performed a laboratory study to investigate the problem of when a predator should terminate search in a given patch of prey and move on to the next one. Gibb's and Krebs' hypotheses of number and time expectation and Charnov's optimization model were tested. Two groups of ovenbirds (Seiurus aurocapillus) were trained to find two or four prey. Subsequently the prey densities were suddenly reversed. We found no evidence that birds hunted by number or time expectation. Similarly, they did not behave as predicted by Charnov's model. Birds rapidly learned to find prey in the patches. They avoided patches and areas within patches already searched. Thus, the decision of when to leave a patch may coincide with complete coverage. More time was spent per patch at the higher density. This was partly due to area-restricted searching, To the extent that ovenbirds form expectations of where to find food and search selected areas thoroughly, hunting by time expectation cannot be ruled out completely.
The role of free amino acids in cellular osmoregulation in the freshwater bivalve Ligumia subrostrata (Say)
Authors: Hanson J. Alison , Dietz Thomas H.
Published: August 2008

Free amino acids constitute 11% of the cellular solute in Ligumia subrostrata acclimated in pond water but less than 1% of blood total solute. Arginine, glutamate, histidine, and alanine account for 60% of the cellular free amino acid concentration. Tissue free amino acid concentrations increase when the animals are exposed to dehydration and anoxic stress. Free amino acids contributing most to the elevated tissue amino acid concentrations are glutamate, alanine, threonine, and serine. These specific free amino acids play an important role in cellular volume regulation.
Inventaire et classification écologiques des biotopes à larves de moustiques (Culicides) de la région de Radisson (territoire de la Baie de James, Québec)
Authors: Maire Alain , Aubin Antoine
Published: August 2008

Through the 1975 season, an inventory was drawn up of species of mosquitoes in the Radisson area, located in middle-north Quebec, the purpose of which was to set up larval mosquito control. With this inventory is an ecological analysis of the temporary water environment propitious to larval development. Starting with semiquantitative samples from these habitats, the authors attempt to demonstrate associations between the mosquito larvae and the vegetation. The conclusions arrived at are discussed.
Régime alimentaire d'oiseaux fréquentant un agrosystème
Authors: Potvin Normand , Bergeron Jean-Marie , Fernet Camille
Published: August 2008

The gizzard content analysis of red-winged blackbirds, common grackles, cowbirds, starlings, and pigeons allowed us to evaluate the volume of corn and barley ingested by these birds. Our results indicate that all these birds eat invertebrates, except for the pigeon, which consumes only grain. The starling does not eat corn and consumes very little barley. The common grackle has a corn diet of 45.2%, while the red-winged blackbird, the pigeon, and the cowbird consume 23.3%, 17.6%, and 5.7% respectively. Barley also occupies an important place in the diet of these four bird species: 49.9% for the pigeon, 28.3% for the cowbird, 17.4% for the red-winged blackbird, and 14.5% for the common grackle. Oats were noticed in a few common grackle and pigeon gizzards. The volumes of all other species of seeds found in the gizzards were not as great as that of corn and barley. Insects are prevalent, especially Coleoptera, which account for 53.5% of the starlings' diet, 21.0% of the red-winged blackbirds' diet, 18.2% of the cowbirds' diet, and 17.0% of the common grackles' diet.
Experimental analyses of dispersal in snowshoe hare populations
Authors: Windberg Lamar A. , Keith Lloyd B.
Published: August 2008

Dispersal was investigated in snowshoe hare (Lepus americanus) populations near Rochester, Alberta, from May 1970 to May 1974. Ingressing hares (dispersers) were removed every 3 to 4 weeks after removal of the initial resident population from an 11.3-ha study area. Dispersal into this vacant habitat occurred during all seasons of each year. The highest rates of ingress were recorded during the winter of peak population densities (1970–1971). There was a higher proportion of short-yearlings among ingressing hares than among residents. During two winters of known food shortage (1970–1971 and 1971–1972) dispersing hares had lower body weights than residents. Lighter adrenals and a higher incidence of scarring were also found among ingressing hares during winter 1970–1971.During winter 1971–1972 the resident hare population was removed from another area. Comparable recapture rates between marked immigrants on this area and hares on unmanipulated study areas indicated that ingressing individuals had settled in the vacant habitat.Hare population response to sex-ratio imbalance, created by partial removal of each sex on different areas, was studied during 1970 and 1971. Pregnancy rates declined significantly only on the male-removal area. Movements by adults during the breeding season and by predominantly juveniles over winter tended toward rebalancing population sex ratios.
Structure of the labial palp of a larval elaterid (Coleoptera) and of sinus cells associated with its sensilla
Authors: Bellamy F. W. , Zacharuk R. Y.
Published: August 2008

Within each labial palp of the larval elaterid Ctenicera destructor (Brown) there is a terminal distal lymph sinus that is separated from the hemocoel in the prementum by a cellular mass in the distal two-thirds of the palp. The sensory neurons of the terminal sensilla form two ganglia that extend from the cellular mass into the prementum. Two types of cells intersperse and surround the cells associated with the sensilla. Elongate gobletlike cells, termed hemolymph sinus cells, extend from the hemocoel to the distal lymph sinus within the ganglia and through the cellular mass. Each contains a sinusoid that opens into the distal sinus. Cuboidal cells, termed basal hemolymph cells, are apposed to and interspersed between the bases of the sinus cells. Both types are associated with the basement membrane bounding the hemocoel and seem to transport materials from hemocoel to distal sinus and perhaps also secrete into the latter. Both types of cells may be differentiated hemocytes.
Histopathologic changes in surficial tissues of brook trout, Salvelinusfontinalis (Mitchill), exposed to acute and chronic levels of pH
Authors: Daye P. G. , Garside E. T.
Published: August 2008

Fingerling brook trout, Salvelinusfontinalis (Mitchill), were subjected to acute and chronic pH stress for maximum periods of 10 000 min in a series of continuous-flow dilutions of sulphuric acid or sodium hydroxide from pH 2.2 to 10.8 at 10 and 20 °C after acclimation at 15 °C and pH 6.8. Various tissues, gill, eye, naris, integument, and alimentary tract, were examined histologically and compared with control samples kept at pH 6.8. No differences in the degree or form of tissue injury were detected between series for corresponding pH levels at 10 and 20 °C. Thresholds for tissue and cellular derangements were pH 5.2 and 9.0. Mucous cells of gills, nares, and integument exhibited progressive degrees of hypertrophy and excessive secretion of mucus with increased pH stress. Epithelial necrosis and sloughing occurred extensively on gills, corneae, and integument. At the lethal levels (pH 3.5 and 9.8), epithelial necrosis also occurred in the esophagus. No cellular injury was detected in the stomach or any part of the intestine.
Effect of the cestode Ligula intestinalis on spottail shiners, Notropis hudsonius
Authors: Mahon Robin
Published: August 2008

Ninety six of 292 field-collected Notropis hudsonius were parasitized by the cestode Ligula intestinalis. All but two of the infected fish were over 1 year old. Infection sterilized the fish, and heavy infections were associated with poor condition and small size. The parasites were distributed among the fish more uniformly than would have been expected by chance.
Male fathead minnows (Pimephales promelas Rafinesque) retain their fright reaction to alarm substance during the breeding season
Authors: Smith R. J. F.
Published: August 2008

In laboratory and field tests, breeding male fathead minnows respond to conspecific skin extract with a fright reaction despite their own seasonal loss of alarm substance cells. Their fright reaction is facilitated by the presence of other fatheads.
Parental behavior of intertidal fishes of the stichaeid genus Xiphister
Authors: Marliave Jeffrey B. , DeMartini Edward E.
Published: August 2008

Egg masses of Xiphister atropurpureus (Kittlitz) and X. mucosus (Girard) are tended by a single adult male wrapped closely around the mass. Males tend up to three egg masses at once. It is suggested that males only tend egg masses that they have fertilized. Comparison of egg numbers in spawned masses and in ovaries of gravid females, together with the observation of complete egg extrusion by spent females, demonstrates that each mass comprises the entire annual egg output of a female. Therefore, during a season a male may repeatedly spawn with different females.
Redescription of Oswaldocruzia pipiens Walton, 1929 (Nematoda: Trichostrongylidae) from amphibians of eastern North America
Authors: Baker M. R.
Published: August 2008

Oswaldocruzia pipiens Walton, 1929 from the small intestine of Rana pipiens Shreber, R. sylvatica LeConte, R. clamitans melanota Latreille, Pseudacris triseriata triseriata Wied, Hyla versicolor LeConte, and Bufo americanus americanus Holbrook from southern Ontario is redescribed. O. collaris Walton, 1929 and O. euryceae Reiber, Byrd and Parker, 1940 are regarded as synonyms of O. pipiens. O. leidyi Travassos, 1917 is regarded as a nomen nudum and O. waltoni Ingles, 1936 and O. minuta Walton, 1941 as species inquirendae. O. pipiens most closely resembles O. goezei Skrjabin and Schulz, 1952. However, the terminal ends of the lateral distal processes of the spicules are divided into numerous small projections in O. goezei, whereas in O. pipiens each process divides into two incompletely separated projections. There is a slender, lateral spur on each lateral distal process in O. goezei, which are not present in O. pipiens.
Histogenesis of the oropharyngeal and oesophageal mucosa as related to early feeding in rainbow trout, Salmo gairdneri Richardson
Authors: Twongo Timothy K. , MacCrimmon Hugh R.
Published: August 2008

The histogenesis of the oropharyngeal and oesophageal mucosa of rainbow trout, Salmo gairdneri, eleutheroembryos was studied from hatching to day 40 in relation to early feeding. Numbers of epithelial layers of the mucosa increased appreciably until day 20 but little thereafter. Differentiation of mucous cells was evident by day 10 and increased rapidly in number until about day 20. The first structurally distinct taste buds were observed in the oropharyngeal mucosa at day 8 and appeared by day 20 to be fully differentiated. An epithelial cell plug that occluded the upper alimentary canal and would have prevented passage of food into the stomach disappeared at about day 17. Teeth, although developing under the mucosa by day 3, had not yet erupted at day 22, the time of first feeding.It is suggested that the onset of first feeding in rainbow trout is in synchrony with the histogenesis of the oropharyngeal mucosa, notably the mucous cells and taste buds. The oropharyngeal mucosa of the fish that failed to feed by day 37 appeared to have undergone extensive hyperplasia while mucous cells were atypical, and taste buds seemingly deformed.
Observations on the occurrence and collection of mermithid nematodes from blackflies (Diptera: Simuliidae)
Authors: Bailey C. H. , Gordon R.
Published: August 2008

From 1973 through 1975 larval blackflies were sampled for mermithid nematodes in 83 streams in Newfoundland. Prosimulium mixtum/fuscum and Simulium venustum were the predominant hosts of the mermithid Neomesomermis flumenalis but rates of infection in late-instar larvae were generally low (4.3 ± 0.7% and 5.4 ± 1.2% for P. mixtum/fuscum and S. venustum respectively). Mermithid infection in the streams studied showed temporal fluctuations and varied among and within host breeding sites. When numbers of parasitized larvae were judged adequate, mass collections of larvae were made and held in the laboratory for emergence of mermithids. Nematode emergence was in two distinct peaks, one for the Prosimulium generation the other for the first generation of S. venustum. The temporal separation of the peaks varied from year to year owing to weather. Observations on the bionomics of both mermithids and blackfly hosts made during the course of the surveys and technical problems inherent to such studies are discussed.
Effect of synthetic luteinizing hormone – releasing hormone (LH–RH) on ovarian development in Japanese medaka, Oryzias latipes
Authors: Chan Kenneth Ka-Sing
Published: August 2008

Regressed female medakas were injected with synthetic luteinizing hormone–releasing hormone (LH–RH) intraperitoneally twice a week for 6 weeks under warm temperature (23 ± 1 °C) and short photoperiod (8 h light: 16 h dark). A dose response was observed as shown by the gonadosomatic index and the percentage distribution of class III oocytes with yolk formation. Ovulation also occurred in fish injected with the highest dose. Pituitary cytology revealed stimulation of gonadotropic cells in the proximal pars distalis by synthetic LH–RH at doses of 100 and 1000 ng per gram body weight. Thus, synthetic LH–RH seems to be effective in inducing ovarian development in the medaka. In fish, the presence of a system similar to the mammalian LH–RH system seems likely.
Influence of salinity on ultrastructure of the secretory cells of the adenohypophyseal pars distalis in yearling coho salmon (Oncorhynchus kisutch)
Authors: Nagahama Yoshitaka , Clarke W. Craig , Hoar W. S.
Published: August 2008

Six different types of secretory cells were identified by light and electron microscopy in the adenohypophyseal pars distalis of yearling coho salmon acclimated to fresh or salt water. Prolactin cells are markedly more active in the freshwater than the seawater fish; these cells exhibit definite functional activity 3 days after transfer from salt to fresh water, indicating an osmoregulatory role of prolactin in the freshwater environment. Plasma sodium showed a significant decline 6 h after transfer from sea water to fresh water and, even after 1 week, remained lower than in the fully acclimated freshwater fish. Corticotropic (ACTH) cells did not appear cytologically different in freshwater and seawater fish. GH cells, the most prominent cells in the proximal pars distalis, appear more numerous and more granulated in the seawater fish, suggesting an osmoregulatory involvement in young coho salmon. Putative thyrotropic (TSH) and putative gonadotropic cells (GTH) can be distinguished by differences in granulation; only one type of GTH cell is evident with ultrastructural features that differ from those of sexually mature salmon. Stellate, non-granulated cells occur in all regions of the adenohypophysis but more frequently in the prolactin follicles; they are much more prominent in the seawater than freshwater fish.
The descriptive and comparative postcranial osteology of marten (Martes americana Turton) and fisher (Martes pennanti Erxleben): the appendicular skeleton
Authors: Leach Doug
Published: August 2008

The morphological characteristics of the appendicular skeleton of 26 adult fisher and 55 adult marten were studied to determine those characteristics that could be used to distinguish between species and sexes. Measurements and illustrations were used to supplement the descriptions of most bones. The appendicular skeletons of marten and fisher are similar in structure but it is possible to distinguish between the skeletal elements of these mustelids using morphometric data. Distinction can also be made between certain postcranial skeletal remains of males and females within each species using bone measurements.
Digestive processes of haematophagous insects. XII. Secretion of trypsin and carboxypeptidase B by Glossina morsitans morsitans Westwood (Diptera: Glossinidae)
Authors: Gooding R. H.
Published: August 2008

There was a significant positive correlation between protein content and the amounts of trypsin and carboxypeptidase B (CPB) in the digestive portion of the midgut of Glossina morsitans morsitans, 24, 48, 72, and 96 h after feeding on a rabbit. CPB and trypsin activity were also positively correlated. Trypsin and CPB production were stimulated, to varying degrees, by bovine serum albumin (BSA), α-globulin, β-globulin, γ-globulin, and haemoglobin; the greatest response was to BSA. Peptides derived from BSA by trypsin cleavage also stimulated production of trypsin and CPB.
A surface preparation study on the effect of methyl mercury on the sensory hair cell population in the cochlea of the harp seal (Pagophilus groenlandicus Erxleben, 1777)
Authors: Ramprashad F. , Ronald K.
Published: August 2008

Surface preparations of the organ of Corti of four harp seals were used to study the effect of prolonged ingestion of methyl mercury on the sensory cell population.A low level of damage to the sensory hair cells occurred throughout the length of the cochlea. Damage was confined to the three outer rows of sensory hair cells especially the third outermost row. At each location along the length of the cochlea, sensory hair cell damage in the seals on a daily dose of 25.0 mg/kg of methyl mercury exceeded the damage to the cochlea of the seals fed on a daily dose of 0.25 mg/kg of methyl mercury. Greatest damage in all the mercury-treated seals occurred in the middle coil of the cochlea. Seals on the higher mercury diet showed a 20–24% sensory cell damage at the upper middle coil, about 19–26 mm from the base, whereas only 4–5% damage was found within same region in the cochlea of the seals on the lower mercury diet.This lack of specificity and low level of damage to the sensory hair cells seems characteristic of mercury and is a direct contrast to other known ototoxic agents.
Amino acid composition of casein isolated from the milks of different species
Authors: Lauer Bruce H. , Baker Bruce E.
Published: August 2008

Casein was isolated from the milks of the following species: cow, horse, pig, reindeer, caribou, moose, harp seal, musk-ox, polar bear, dall sheep, and fin whale. The caseins were subjected to acid hydrolysis, the resultant amino acids were converted to their n-butyl-N-trifluoroacetyl esters, and the amino acid composition of the caseins was determined by gas chromatographic analysis of these esters. Notable among the results was the close similarity, with respect to amino acid composition, of reindeer and caribou caseins. The results of the amino acid analyses of the other caseins are presented and discussed.
The effects of feeding microsporidian (Nosema fumiferanae) spores to naturally infected spruce budworm (Choristoneura fumiferana)
Authors: Wilson G. G.
Published: August 2008

Infection of spruce budworm, Choristoneura fumiferana, in nature by Nosema fumiferanae has an adverse effect on the host. Larval and pupal mortality are increased, while female pupal weights, adult longevity, and fecundity are significantly reduced by feeding additional microsporidian spores to naturally infected spruce budworm.
Annual variations of red and white cell count in the urodele Taricha granulosa
Authors: Friedmann G. B.
Published: August 2008

An average of 50 red blood cells and 5 white blood cells per field with 500 × magnification is subject to substantial seasonal variations. These variations seem to offer a good indicator of the stage of the annual cycle of this urodele.
Effects of thyroxine administration on plasma thyroxine levels in the goldfish, Carassius auratus L.
Authors: Hurlburt Mary E.
Published: August 2008

Pellet implantation, immersion, or feeding of thyroxine (T4) raised plasma T4 levels above values of control fish (usually less than 1 μg/100 ml). Values for treated fish in the lower dosage groups generally fell between 1 and 4 μg/100 ml, while in the higher dosage groups plasma T4 levels ranged from 5 to 16 μg/100 ml.
Measurement of L-thyroxine and 3,5,3′-triiodo-L-thyronine levels in fish plasma by radioimmunoassay
Authors: Brown Scott , Eales J. G.
Published: August 2008

Radioimmunoassay (RIA) procedures suitable for measuring L-thyroxine (T4) and 3,5,3′-triiodo-L-thyronine (T3) levels in 0.1 ml of rainbow trout plasma are described. Mean detection limits were 12.5 ng/100 ml (T4 RIA) and 9.5 ng/100 ml (T3 RIA); mean indices of precision were 0.056 (T4 RIA) and 0.042 (T3 RIA). Both 'within' and 'between' assay reproducibilities were satisfactory. Mean T4 levels in two plasma pools from 2-year-old trout were 157 and 171 ng/100 ml; mean T3 levels in two other plasma pools were 130 and 204 ng/100 ml.
Oxygen consumption of a large, cold-adapted frog egg (Ascaphus truei (Amphibia: Ascaphidae))
Authors: Brown Herbert A.
Published: August 2008

Female Ascaphus lay a small number of large eggs beneath rocks in cold, montane streams of the Pacific Northwest. Average number of eggs per female is 45 (range, 28 to 64) and average egg diameter is 4 mm (range, 3.5 to 4.5). The large eggs of Ascaphus contain a relatively large amount of nutrients. Average wet weight of a single egg is 37.5 mg and dry weight is 23.7 mg (63% of wet weight). The oxygen consumption rate of embryos during development at 15 °C increases gradually during cleavage (0.25 μl O2/h per embryo) and more rapidly during neurula and postneurula stages (0.60 to 0.90 μl O2/h per embryo) to a value of 1.20 μl O2/h per embryo at vitelline circulation. The cold-adapted eggs of Ascaphus are characterized by large size, slow developmental rate and low oxygen consumption rate.
Cellular reactions of field crickets (Achetapennsylvanicus Burmeister) and German cockroaches (Blatella germanica L.) to Physaloptera maxillaris Molin (Nematoda: Physalopteroidea)
Authors: Cawthorn Richard J. , Anderson Roy C.
Published: August 2008

The site of development, survival of larvae, and reaction to the presence of Physaloptera maxillaris in field crickets (Acheta pennsylvanicus) and German cockroaches (Blatella germanica) were compared. The preferred site of development in crickets was the villous segment of the ileum. Few larvae became melanized. Larvae developed mainly in the colon in cockroaches and numerous larvae became melanized and died.Most larvae developed in capsules within the hindgut. Each capsule was a giant cell with large nuclei and granular cytoplasm derived from coalesced epithelial cells. Larvae apparently ingested capsule contents. In cockroaches the capsule walls were thin and haemocytes invaded the capsule and melanization destroyed many larvae. Capsules in crickets were thick walled; few haemocytes invaded them, little melanization occurred, and most larvae survived for long periods. Larvae which penetrated directly into the haemocoel were surrounded by haemocytes and became melanized.
Etude cytologique des organes photorécepteurs de la Planaire australienne Cura pinguis
Authors: Durand Jacques P. , Gourbault Nicole
Published: August 2008

The photoreceptors of the australian planarian Cura pinguis were studied by light and electron microscopy. They consist of two different cell types (=primitive type), a cup of pigment cells, and 25 to 30 bipolar visual cells. Cytoplasmic extensions of the pigment cells close the eye opening but leave the dendritic stalk free. This study shows that the morphological characteristics suggest a metabolic cellular activity with the presence of components implied in the visual processes. In animals kept in the dark, the microvilli have a less regular appearance and some material accumulates in the spaces between the visual and pigment cells. The efferent innervation displays a narrow connection with the brain.
Action du jeûne et de Bacillus thuringiensis Berliner sur les protéines plasmatiques de Choristoneura fumiferana (Clem.) (Lepidoptera : Tortricidae)
Authors: Paré F. , Huot L. , Perron J. M. , Cloutier M.
Published: August 2008

Total protein contents of the hemolymph of Choristoneura fumiferana larvae, prepupae, and pupae were studied. These were electrophoretically separated into 14 bands, classified as slow moving and fast moving proteins. During the sixth instar, hemolymph protein contents increased eight to nine times in control larvae mainly owing to slow moving proteins. Protein concentration of slow moving proteins were less pronounced in larvae that were starved and treated with Bacillus thuringiensis, the treated larvae being more affected than the starved larvae. Larvae treated on day 1 of the 6th instar were more affected than those treated on day 4.
Rhythmic colour change of the killifish, Fundulus heteroclitus
Authors: Kavaliers M. , Abbott F. S.
Published: August 2008

A photoelectric method was developed to continuously record the colour of Fundulus heteroclitus. Subsequent recording revealed the existence of an endogenous rhythm of colour change with a period of 22 h 30 min to 26 h 30 min, and an amplitude of 2.5 Ostwald units. Light–dark cycles had a masking rather than entraining effect on colour change. Temperature–salinity alterations were also ineffective in entrainment. Blinding the fish did not affect the rhythm. Hypophysectomy extinguished the rhythm of colour change, but did not affect the ability to adapt to different backgrounds.
Estrogenic effects of the enantiomers of o,p′-DDT in Japanese quail
Authors: McBlain W. A. , Lewin V. , Wolfe F. H.
Published: August 2008

Immature female Japanese quail were given three daily intraperitoneal injections of (±)-o,p′-DDT, (−)-o,p′-DDT, or (+)-o,p′-DDT. Seventy-two hours after the first injection the oviducts were excised and the estrogen-sensitive parameters, oviducal wet weight and oviducal glycogen content, were measured. The levo enantiomer of o,p′-DDT was a more active estrogen than the dextro form in the immature female quail. The differing estrogenic activities of the o,p′-DDT enantiomers apparently were not the result of a differential transport within the birds. A dietary dose of 200 ppm of (±)-o,p′-DDT was not estrogenic in immature female quail when administered for 3 or 7 days. Neither enantiomer of o,p′-DDT was able to offset a light-stimulated testicular wet weight increase in male Japanese quail.
The mechanics of proboscis extension by the blowfly Phormia regina Meigen
Authors: Thomson A. J.
Published: August 2008

The mechanism of extension of the rostrum is based on the activity of the muscles which run from the gena to the tips of the posterior cornua of the fulcrum. These muscles have previously been erroneously ascribed the function of retractors of the fulcrum but are redefined as rostral protractors. A mechanism for the mode of action of neural feedback in the regulation of feeding threshold is proposed, based on the properties of the proboscis extension–retraction system.
Ecological aspects of winter dormancy in the striped skunk (Mephitis mephitis)
Authors: Mutch Graham R. P. , Aleksiuk Michael
Published: August 2008

Seasonal surface activity patterns of captive and free-ranging skunks at Delta Marsh, Manitoba, Canada, were determined using radio telemetry and visual observations. Activity decreased sharply between September and mid-December, and was virtually nil between December and early April. Surface activity resumed in March and increased sharply in April to summer levels.Body temperature (Tb) was studied in two individuals in July and three individuals in other months using abdominally implanted radio transmitters. Mean Tb, maximum diel range, and minimum Tb were 37.7, 2.2, and 36.2 °C respectively in July, and 34.4, 7.2, and 28.4 °C in January.Body fat content of adult males, determined by ether extraction, was 32% of live weight in October, and 10% in late April and early May. Theoretically, the skunks experience an energy deficit of 44% if they exist at basal metabolic levels for a winter period of 140 days. The winter reduction in surface activity, the retreat to a relatively warm den, and the winter depression in body temperature permit the striped skunk in the northern portion of its range to survive the winter relying exclusively on stored fat as an energy source, without resort to true physiological hibernation.
Capillaria didelphis n.sp. (Nematoda: Trichuroidea) from the opossum, Didelphis virginiana L. in Georgia
Authors: Butterworth Eric W. , Beverley-Burton Mary
Published: August 2008

Capillaria didelphis n.sp. (Nematoda: Trichuroidea) is proposed for worms found in the bronchioles and alveolar spaces in the lungs of opossum, Didelphis virginiana L., in Georgia, U.S.A. Capillaria didelphis has a spinose cirrus and is readily distinguished by one inwardly directed, dorsolateral papilla and one ventral papilla on each lateral lobe of the male posterior extremity. The egg shell is pitted. Capillaria didelphis is compared with C. aerophila, which is apparently confined to the trachea and bronchi of its hosts, and three other species of Capillaria, which have been reported from didelphids: C. fluminensis, C. auritae, and C. longicauda.
Regeneration of limbs autotomized at different times in the fiddler crab, Uca pugilator
Authors: Weis Judith S.
Published: August 2008

After autotomy and partial regeneration of two limb buds in Uca pugilator (16-mm carapace width), crabs were induced to autotomize two or five additional limbs when the bud of the first walking leg had reached an R value of 10 or 15. These procedures caused an acceleration of growth in the initially regenerating limb buds and hastened ecdysis. The two or five additional limbs were replaced very rapidly and were complete at ecdysis.After autotomy and partial regeneration of four limbs in small (12- to 13-mm) crabs, an additional one or three limbs were removed. If the limbs were autotomized when R1 was 10–16, ecdysis was delayed somewhat and the limbs were replaced rapidly. However, if the one or three additional limbs were autotomized when R1 was greater than 16, ecdysis was not delayed and the limbs were not replaced before ecdysis.These results are quite different from those obtained when some growing limb buds, rather than intact limbs, were removed after partial regeneration. The differing results are believed to be due to (1) differences in initial regeneration rate owing to the differing number of limbs originally autotomized, and (2) different responses of the neuroendocrine system to the removal of limbs vs. the removal of limb buds during proecdysis.
Na+:K+- and HCO3−-stimulated ATPase activities in the gills and kidneys of thermally acclimated rainbow trout, Salmo gairdneri
Authors: McCarty L. S. , Houston A. H.
Published: August 2008

Gill and kidney Mg2+-dependent, Na+:K+- and HCO3−-stimulated ATPase (EC 3.6.1.3) activities were estimated at 25 °C and at acclimation temperature in rainbow trout, Salmo gairdneri, acclimated to 2, 10, and 18 °C, as were plasma levels of sodium, potassium, and chloride. Sodium and chloride exhibited no significant variation between 2 and 18 °C; potassium levels were elevated at 18 °C. When assayed at 25 °C Mg2+-dependent and HCO3−-stimulated ATPase activities did not vary consistently or significantly in relation to acclimation temperature. Under comparable assay conditions both gill and kidney Na+:K+-stimulated activities declined at higher acclimation temperatures. Significant increases in all activities were encountered when preparations were incubated at the appropriate acclimation temperature. The data suggest that the branchial Na+:K+–ATPase system serves primarily as a high-temperature amplifier of sodium uptake, and may contribute little to the maintenance of sodium balance in the cold-adapted animal. No evidence of a critical involvement of HCO3−-stimulated ATPase in ionic regulations was obtained.
Identification of origins of lesser snow geese by X-ray spectrometry
Authors: Kelsall John P. , Burton Roland
Published: August 2008

An attempt to apply computer-controlled. X-ray spectrometric methods for the identification of origins of waterfowl, through the analysis of chemical elements in their primary flight feathers, is described. Materials were gathered from three geographically distinct populations of wild lesser snow geese (Chen caerulescens). They were laundered, dried, and irradiated by 25 mCi (1 Ci = 37 GBq) Americium 241. Chemical spectra were developed using a lithium-drifted silicon detector, and a computer-controlled pulse-height analyzer that provided results in 512 channels of emission energy between about 2.3 and 40 keV. Computer programs were written or adapted to process our data. Multivariate discriminant functions were used (among other techniques) to examine potential significant differences between populations, and between different year classes within one population. Attempts were made to classify unknown feathers through use of discriminant functions. Best results were obtained by measuring the areas under K alpha peaks of emission energy for recognizable chemical elements in the spectra and using those, and the times for analysis, as significant variables. Two other methods of using the data are compared with that method. Efforts to discriminate geographically different populations, and to classify unknowns are encouraging. However, there are residual problems to be dealt with.
Sublethal effects of lead acetate on the Y-maze performance of albino mice (Mus musculus L.)
Authors: Ogilvie David M.
Published: August 2008

To determine if lead exposure could impair learning ability, the swimming performance of albino mice in a double Y maze was studied after 2 weeks of treatment with a 10-mg/ml drinking solution of lead acetate. This dose was sublethal and although it depressed weight gain, no overt symptoms of toxicity were observed. Lead-treated mice swam the maze significantly slower than the controls, and 40% of these animals were unable to perform to criterion, apparently because of a lead-induced impairment of locomotor ability. The lead-treated animals which did reach criterion required slightly more trials to do so than the controls, and they made significantly more errors. This finding suggests that the lead may have interfered with learning per se, in addition to causing a motor disability.
The breeding biology of two Lake Erie herring gull colonies
Authors: Morris Ralph D. , Haymes Gerard T.
Published: August 2008

The breeding biology of two Lake Erie herring gull colonies was studied from 1973 to 1976, emphasizing effects of clutch size and time of clutch initiation on reproductive success. In 1976, incubation attention of two-egg and three-egg clutches started early and late in the season was measured with a 20-pen event recorder. Chlorinated hydrocarbon residues in eggs were assessed in 2 years. Nest density was greater, clutch initiation more synchronized, and hatching success higher at one of the colonies. Hatching success and fledging success were independent of clutch size bin early nesters were more successful than late nesters. Differences in hatching success between two-egg and three-egg clutches were a function of time of clutch initiation such that the clutch size with the greater proportion of its nests in the early period had a higher hatching success. The reproductive success of the Lake Erie colonies was intermediate among rates reported for other Great Lakes colonies but below those of most eastern North American or European colonies. There were no significant differences in the incubation attention between two-egg clutches and three-egg clutches or between early and late three-egg clutches. Most clutches were incubated greater than 95% of the time although clutches incubated less than 75% realized the same hatching success.