|   | 
Details
   web
Records
Author (up) Dugatkin, L.A.; Godin, J.-G.J.
Title Female mate copying in the guppy (Poecilia reticulata): age-dependent effects Type Journal Article
Year 1993 Publication Behavioral Ecology Abbreviated Journal Behav. Ecol.
Volume 4 Issue 4 Pages 289-292
Keywords mate choice, copying, guppy, Poecilia reticulata
Abstract Virtually all studies of mate choice to date have assumed that females choose mates independent of one another. Social cues, however, such as the mate choice of conspecifics, may also play an important role in such decisions. Previous work has shown that female guppies of similar age copy each other's choice of mates. Here we examine the effect of relative age on mate choice copying in the guppy, Poecilia reticulata, and examine whether younger individuals are more likely to copy the mate choice of older conspecifics than vice versa. Results indicate that younger females copy the mate choice of older females, but older individuals do not appear to be influenced by the mate choice of younger individuals.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 2181
Permanent link to this record
 

 
Author (up) Dugatkin, L.A.; Godin, J.G.
Title Reversal of female mate choice by copying in the guppy (Poecilia reticulata) Type Journal Article
Year 1992 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci
Volume 249 Issue 1325 Pages 179-184
Keywords Acclimatization; Animals; *Choice Behavior; Female; Male; Poecilia; *Sexual Behavior, Animal
Abstract Ever since Fisher (1958) formalized models of sexual selection, female mate choice has been assumed to be a genetically determined trait. Females, however, may also use social cues to select mates. One such cue might be the mate choice of conspecifics. Here we report the first direct evidence that a female's preference for a particular male can in fact be reversed by social cues. In our experiments using the Trinidadian guppy (Poecilia reticulata), this reversal was mediated by mate-copying opportunities, such that a female (the 'focal' female) is given the opportunity to choose between two males, followed by a period in which she observes a second female (the 'model' female) displaying a preference for the male she herself did not prefer initially. When allowed to choose between the same males a second time, compared with control tests, a significant proportion of focal females reversed their mate choice and copied the preference of the model female. These results provide strong evidence for the role of non-genetic factors in sexual selection and underlie the need for new models of sexual selection that explicitly incorporate both genetic and cultural aspects of mate choice.
Address Department of Biology, Mount Allison University, Sackville, New Brunswick, Canada
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0962-8452 ISBN Medium
Area Expedition Conference
Notes PMID:1360679 Approved no
Call Number Serial 1824
Permanent link to this record
 

 
Author (up) Dugnol, B.; Fernández, C.; Galiano, G.
Title Wolf population counting by spectrogram image processing Type Journal Article
Year 2007 Publication Appl Math Comput Abbreviated Journal
Volume 186 Issue Pages
Keywords
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Dugnol2007 Serial 6464
Permanent link to this record
 

 
Author (up) Dugnol, B.; Fernández, C.; Galiano, G.; Velasco, J.
Title On a chirplet transform-based method applied to separating and counting wolf howls Type Journal Article
Year 2008 Publication Signal Process Abbreviated Journal
Volume 88 Issue Pages
Keywords
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Dugnol2008 Serial 6466
Permanent link to this record
 

 
Author (up) Dugnol, B.; Fernández, C.; Galiano, G.; Velasco, J.
Title Implementation of a diffusive differential reassignment method for signal enhancement: An application to wolf population counting Type Journal Article
Year 2007 Publication Appl Math Comput Abbreviated Journal
Volume 193 Issue Pages
Keywords
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Dugnol2007 Serial 6465
Permanent link to this record
 

 
Author (up) Dumont, B.; Rossignol, N.; Loucougaray, G.; Carrère, P.; Chadoeuf, J.; Fleurance, G.; Bonis, A.; Farruggia, A.; Gaucherand, S.; Ginane, C.; Louault, F.; Marion, B.; Mesléard, F.; Yavercovski, N.
Title When does grazing generate stable vegetation patterns in temperate pastures? Type Journal Article
Year 2012 Publication Agriculture, Ecosystems & Environment Abbreviated Journal
Volume 153 Issue Pages 50-56
Keywords Boolean process; Cattle; Patch stability; Productivity; Stocking density; Temperate pasture
Abstract The stability of grazing-induced spatial patterns of vegetation was analyzed at two spatial scales (25 m × 20 m areas and 1.6 m × 0.8 m grids) in pastures of contrasting productivity (maximum standing biomass: 130–800 gDM/m2). At both scales, the mosaic of grazed and ungrazed patches was modeled as a Boolean process, calculating cross-variograms to quantify the temporal stability of grazing patterns and its links with local floristic composition were tested. The scale at which stability of vegetation patterns took place in two successive years depended on pasture productivity. Inter-annual stability of large-scale patterns mainly occurred in extensively used fertile pastures grazed by cattle, and in pastures grazed by horses. Less-fertile grasslands were mainly characterized by a fine-scale stability of grazing patterns. Stable fine-scale patterns were often related to the local abundance of legumes and forbs. Stable large-scale patterns of grazing within lightly grazed productive grasslands could result in divergent local vegetation dynamics, which can be seen as an opportunity for restoring biodiversity in fertile grasslands.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0167-8809 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5595
Permanent link to this record
 

 
Author (up) Duncan, P.; Foose, T. J.; Gordon, I. J.; Gakahu,C. G.; Lloyd, M.
Title Comparative nutrient extraction from forages by grazing bovids and equids: a test of the nutritional model of equid/bovid competition and coexistence Type Journal Article
Year 1990 Publication Oecologia Abbreviated Journal Oecologia
Volume 84 Issue 3 Pages 411-418
Keywords Ruminant – Hind-gut fermenter – Intake – Digestion – Competition
Abstract Ruminants are unevenly distributed across the range of body sizes observed in herbivorous mammals; among extant East African species they predominate, in numbers and species richness, in the medium body sizes (10-600 kg). The small and the large species are all hind-gut fermenters. Some medium-sized hind-gut fermenters, equid perissodactyls, coexist with the grazing ruminants, principally bovid artiodactyls, in grassland ecosystems. These patterns have been explained by two complementary models based on differences between the digestive physiology of ruminants and hind-gut fermenters. The Demment and Van Soest (1985) model accounts for the absence of ruminants among the small and large species, while the Bell/Janis/Foose model accounts both for the predominance of ruminants, and their co-existence with equids among the medium-sized species (Bell 1971; Janis 1976; Foose 1982). The latter model assumes that the rumen is competitively superior to the hind-gut system on medium quality forages, and that hind-gut fermenters persist because of their ability to eat more, and thus to extract more nutrients per day from high fibre, low quality forages. Data presented here demonstrate that compared to similarly sized grazing ruminants (bovids), hind-gut fermenters (equids) have higher rates of food intake which more than compensate for their lesser ability to digest plant material. As a consequence equids extract more nutrients per day than bovids not only from low quality foods, but from the whole range of forages eaten by animals of this size. Neither of the current nutritional models, nor refinements of them satisfactorily explain the preponderance of the bovids among medium-sized ungulates; alternative hypotheses are presented.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes from Professor Hans Klingels Equine Reference List Approved yes
Call Number Serial 1035
Permanent link to this record
 

 
Author (up) Dunn, M.F.; Branlant, G.
Title Roles of zinc ion and reduced coenzyme in horse liver alcohol dehydrogenase catalysis. The mechanism of aldehyde activation Type Journal Article
Year 1975 Publication Biochemistry Abbreviated Journal Biochemistry
Volume 14 Issue 14 Pages 3176-3182
Keywords *Alcohol Oxidoreductases/metabolism; Aldehydes/*pharmacology; Animals; Binding Sites; Enzyme Activation/drug effects; Horses; Hydrogen-Ion Concentration; Kinetics; Liver/enzymology; *NAD/analogs & derivatives/pharmacology; Oxidation-Reduction; Protein Binding; Spectrophotometry; Spectrophotometry, Ultraviolet; Temperature; *Zinc/pharmacology
Abstract 1,4,5,6-Tetrahydronicotinamide adenine dinucleotide (H2NADH) has been investigated as a reduced coenzyme analog in the reaction between trans-4-N,N-dimethylaminocinnamaldehyde (I) (lambdamax 398 nm, epsilonmax 3.15 X 10-4 M-minus 1 cm-minus 1) and the horse liver alcohol dehydrogenase-NADH complex. These equilibrium binding and temperature-jump kinetic studies establish the following. (i) Substitution of H2NADH for NADH limits reaction to the reversible formation of a new chromophoric species, lambdamax 468 nm, epsilonmax 5.8 x 10-4 M-minus 1 cm-minus 1. This chromophore is demonstrated to be structurally analogous to the transient intermediate formed during the reaction of I with the enzyme-NADH complex [Dunn, M. F., and Hutchison, J. S. (1973), Biochemistry 12, 4882]. (ii) The process of intermediate formation with the enzyme-NADH complex is independent of pH over the range 6.13-10.54. Although studies were limited to the pH range 5.98-8.72, a similar pH independence appears to hold for the H2NADH system. (iii) Within the ternary complex, I is bound within van der Waal's contact distance of the coenzyme nicotinamide ring. (iv) Formation of the transient intermediate does not involve covalent modification of coenzyme. Based on these findings, we conclude that zinc ion has a Lewis acid function in facilitating the chemical activation of the aldehyde carbonyl for reduction, and that reduced coenzyme plays a noncovalent effector role in this substrate activating step.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0006-2960 ISBN Medium
Area Expedition Conference
Notes PMID:238585 Approved no
Call Number Equine Behaviour @ team @ Serial 3817
Permanent link to this record
 

 
Author (up) Dvoinos, G.M.; Kharchenko, V.A.; Zviagnitsova, N.S.
Title The characteristics of the helminth community in the Turkmen kulan (Equus hemionus) Type Journal Article
Year 1992 Publication Parazitologiia Abbreviated Journal Parazitologiia
Volume 26 Issue 3 Pages 246-251
Keywords Animals; Female; Helminthiasis/parasitology; Helminthiasis, Animal; Helminths/classification/*isolation & purification; Male; Perissodactyla/*parasitology; Turkmenistan; Ukraine
Abstract The helminth fauna of 24 kulans from Askaniya-Nova and Badkhyz was studied. 42 species of helminths were found, 34 of which belong to strongylids. The helminth species composition of kulan is similar to that of other species of horses. This is a result of an intensive parasite exchange in the historical past when numerous populations of different Equidae species made long seasonal migrations over steppe inter-river lands of Asia and grazed for some time on common pastures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Russian Summary Language Original Title K kharakteristike soobshchestva gel'mintov turkmenskogo kulana (Equus hemionus)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-1847 ISBN Medium
Area Expedition Conference
Notes PMID:1408368 Approved no
Call Number Equine Behaviour @ team @ Serial 2285
Permanent link to this record
 

 
Author (up) Dwan, K.; Altman, D.G.; Arnaiz, J.A.; Bloom, J.; Chan, A.-W.; Cronin, E.; Decullier, E.; Easterbrook, P.J.; Von Elm, E.; Gamble, C.; Ghersi, D.; Ioannidis, J.P.A.; Simes, J.; Williamson, P.R.
Title Systematic Review of the Empirical Evidence of Study Publication Bias and Outcome Reporting Bias Type Journal Article
Year 2008 Publication Plos One Abbreviated Journal Plos One
Volume 3 Issue 8 Pages e3081
Keywords
Abstract Background The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a randomised controlled trial. Study publication bias has been recognised as a potential threat to the validity of meta-analysis and can make the readily available evidence unreliable for decision making. Until recently, outcome reporting bias has received less attention. Methodology/Principal Findings We review and summarise the evidence from a series of cohort studies that have assessed study publication bias and outcome reporting bias in randomised controlled trials. Sixteen studies were eligible of which only two followed the cohort all the way through from protocol approval to information regarding publication of outcomes. Eleven of the studies investigated study publication bias and five investigated outcome reporting bias. Three studies have found that statistically significant outcomes had a higher odds of being fully reported compared to non-significant outcomes (range of odds ratios: 2.2 to 4.7). In comparing trial publications to protocols, we found that 40-62% of studies had at least one primary outcome that was changed, introduced, or omitted. We decided not to undertake meta-analysis due to the differences between studies. Conclusions Recent work provides direct empirical evidence for the existence of study publication bias and outcome reporting bias. There is strong evidence of an association between significant results and publication; studies that report positive or significant results are more likely to be published and outcomes that are statistically significant have higher odds of being fully reported. Publications have been found to be inconsistent with their protocols. Researchers need to be aware of the problems of both types of bias and efforts should be concentrated on improving the reporting of trials.
Address
Corporate Author Thesis
Publisher Public Library of Science Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 6644
Permanent link to this record