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Morphometric Traits (morphometric + trait)
Selected AbstractsDiversity in five goat populations of the Lombardy Alps: comparison of estimates obtained from morphometric traits and molecular markersJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 3 2001P. Crepaldi Phenotypic and genetic variability were studied within and between the goat populations of Bionda dell'Adamello, Frisa, Orobica, Verzaschese and Val di Livo. These are populations reared for most of the year on pastures of the Lombardy Alps, numbering a minimum of 1000 and a maximum of 8000 individuals per breed. The first four are standardized breeds of recent formation; at present they are supported by the European Union measures for the conservation of rare breeds. On the basis of its visible genetic profile the Val di Livo goat may be classified as a primary population. Phenotypic variability was estimated on the basis of six somatic measurements on 60,140 adult goats per breed, whereas genetic variation was measured on the basis of 201 AFLP loci. The partition of the total molecular variation into the within and between breed components indicates that the majority of the molecular variability is conserved within populations, whereas only 8.8% can be attributed to between population variation. Morphometric and molecular marker data produced unrelated distance values and different topology of UPGMA clusters. It may be hypothesized that the morphometric originality of the Val di Livo goat is mostly determined by environmental factors and selection pressure rather than by different origin and genome evolution. Conversely Orobica seems to have diverged from the other breeds at the genome level, which may be explained by an undocumented Southern Italian origin. An objective evaluation of conservation priorities may in the near future be based on the integrated use of molecular markers and of information on quantitative traits and allelic variation with adaptive relevance. Diversité dans cinq populations de chèvres des Alpes lombardes: comparaisons entre estmations obtenues par des mesures somatiques et par des marqueurs moléculaires On a etudié la variabilité phénotypique et génétique entre et parmi les populations de chèvres Bionda dell'Adamello, Frisa, Orobica, Verzaschese et Val di Livo. Il s'agit de populations qui content entre 1000 et 8000 sujets, elevés pour la plus part de l'année sur les pâturages des Alpes de Lombardie. Les quatre premières, actuellement sauvegardées par des mesures communautaires, sont des races à standard recemment constituées. La chèvre de la Val di Livo peut être rangée parmi les races primaires. La diversité phénotypique a été montrée par un dendrogramme obtenus des distances euclidiennes calculées à partir de six mesures somatiques qui avaient été prises sur 60,140 chèvres adultes pour chaque race. La diversité génétique a été montrée par un dendrogramme bâti sur la matrice des distances de Nei obtenues des 201 marqueurs moléculaires AFLP, produits par 7 combinaisons de primers, sur 30 sujets pour chaque race. La décomposition de la variabilité génétique totale estimée par les données moléculaires a montré que la plus part de la variabilité est conservée parmi la population, tandis que seulement l,8,8% peut être imputé aux différences entre populations. Les données moléculaires et somatiques ont donné lieu à des distances qui ne sont pas corrélées et à des cluster avec une topologie nettement différente. La comparaison entre les deux approches permet d'avancer l'hypothèse que l'originalité somatique de la chèvre de la Val di Livo pourrait être due à des facteurs d'environnement et/ou à la pression de sélection plutôt qu'à des facteurs liés à l'évolution du genome. Au contraire ces derniers seraient responsables de l'originalité génétique de la race Orobica et confirmeraient des témoignages orals non documentés. Un choix objectif des ressources génétiques qui méritent d'être conservées pourra probablement se baser sur l'employ conjoint des marqueurs et de renseignements sur les caractères quantitatifs et sur les variantes alléliques des gènes qui ont une valeur adaptative. Diversität in fünf Ziegenpopulationen der lombardischen Alpen: Vergleich von Schätzungen auf der Basis morphologischer Eigenschaften und molekularer Marker Es wurden die phänotypische und genetische Variabilität innerhalb und zwischen Bionda dell'Adamello, Frisa, Orobica, Verzaschese und Val di Livo Ziegenpopulationen untersucht. Diese Populationen, mit Größen zwischen 1000 und 8000 Tieren, werden den größten Teil des Jahres auf Weiden der lombardischen Alpen gehalten. Die vier erstgenannten Populationen sind erst kürzlich standardisierte Rassen; gegenwärtig werden sie mit EU-Mitteln für die Erhaltung seltener Rassen, unterstützt. Auf der Basis des erkennbaren genetischen Profils muß die Rasse Val di Livo als eine Primärpopulation eingeordnet werden. Phänotypische Variabilität wurde auf der Basis von sechs Körpermaßen an 60,140 ausgewachsenen Ziegen je Rasse geschätzt, die genetische Variation wurde auf der Basis von 201 AFLP-Loci gemessen. Die Aufteilung der gesamten molekularen Varianz in Varianzkomponenten innerhalb und zwischen Populationen zeigt, daß der größte Teil der molekularen Variabilität innerhalb der Populationen auftritt, und nur 8,8% der Gesamtvarianz auf die Varianz zwischen den Populationen entfällt. Morphologische und molekulare Marker erzeugten unabhängige Distanzwerte und unterschiedliche upgma-Cluster. Es kann die Hypothese aufgestellt werden, daß die morphologische Einzigartigkeit der Val di Livo Ziege stärker auf Umwelteffekte und Selektionsdruck als auf eine unterschiedliche Herkunft oder genomische Evolution zurückzuführen ist. Dagegen scheint Orobica auf Genomebene von den anderen Rassen abzuweichen, was durch einen nicht dokumentierten süditalienischen Ursprung erklärt werden könnte. Eine objektive Bewertung von Prioritäten für Konservierungsmaßnahmen dürfte in Zukunft auf einen integrierten Gebrauch molekularer Marker, Informationen über quantitative Merkmale sowie der genetischen Variation bezüglich der Adaptationsfähigkeit basieren. [source] Secrets in the eyes of Black Oystercatchers: a new sexing techniqueJOURNAL OF FIELD ORNITHOLOGY, Issue 2 2008Brian M. Guzzetti ABSTRACT Sexing oystercatchers in the field is difficult because males and females have identical plumage and are similar in size. Although Black Oystercatchers (Haematopus bachmani) are sexually dimorphic, using morphology to determine sex requires either capturing both pair members for comparison or using discriminant analyses to assign sex probabilistically based on morphometric traits. All adult Black Oystercatchers have bright yellow eyes, but some of them have dark specks, or eye flecks, in their irides. We hypothesized that this easily observable trait was sex-linked and could be used as a novel diagnostic tool for identifying sex. To test this, we compared data for oystercatchers from genetic molecular markers (CHD-W/CHD-Z and HINT-W/HINT-Z), morphometric analyses, and eye-fleck category (full eye flecks, slight eye flecks, and no eye flecks). Compared to molecular markers, we found that discriminant analyses based on morphological characteristics yielded variable results that were confounded by geographical differences in morphology. However, we found that eye flecks were sex-linked. Using an eye-fleck model where all females have full eye flecks and males have either slight eye flecks or no eye flecks, we correctly assigned the sex of 117 of 125 (94%) oystercatchers. Using discriminant analysis based on morphological characteristics, we correctly assigned the sex of 105 of 119 (88%) birds. Using the eye-fleck technique for sexing Black Oystercatchers may be preferable for some investigators because it is as accurate as discriminant analysis based on morphology and does not require capturing the birds. SINOPSIS El sexado de ostreros en el campo es sumamente difícil dado el caso de que tanto hembras como machos tienen plumaje idéntico y son similares en tamaño. Aunque los ostreros negros (Haematopus bachmani) son sexualmente dimórficos, el utilizar morfometría para determinar su sexo requiere capturar a ambos miembros de la pareja para compararlos, utilizando una análisis discriminativo a modo de asignar un sexo por probabilidad, basado en características morfométricas. Todos los adultos del ostrero negro tienen ojos amarillos y brillantes, pero algunos tienen manchas oscuras en el iris. Tomamos como hipótesis que estas peculiaridades observables estaban ligada al sexo, y que podían ser utilizadas como una herramienta novel de diagnóstico para identificar el sexo en dichas aves. Para poner a pruebas lo mencionado, comparamos datos de ostreros donde se utilizaron marcadores genéticos moleculares (CHD-W/CHD-Z y HINT-W/HINT-Z), análisis morfométrico, y categorías en las manchas en los ojos (manchas marcadas en los ojos, algunas manchitas en los ojos, sin manchas en los ojos). Comparado a marcadores moleculares, encontramos que el análisis discriminativo basado en características morfológicas ofrecía resultados variables asociados a diferencias morfológicas geográficas. Sin embargo, encontramos que las manchas en los ojos estaban ligadas al sexo. Utilizando un modelo de manchas en los ojos, en donde clasificamos como hembras aquellos individuos con manchas pronunciadas en los ojos y a machos con muy pocas manchitas o sin manchitas, le pudimos asignar correctamente el sexo a 117 de 125 (94%) individuos. Utilizando una análisis discriminativo basado en características morfológicas, le asignamos el sexo correctamente a 105 de 119 (88%) individuos. El utilizar la técnica de manchas en los ojos para el sexado de ostreros negros pudiera ser preferible para algunos investigadores porque es más exacto que el análisis discriminativo basado en morfología y porque no requiere que se tenga que capturar a las aves. [source] Morphology and Morphometry of Lingual Papillae in Adult and Newborn Egyptian Fruit Bats (Rousettus aegyptiacus)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2009J. Trzcieli, ska-Lorych Summary The paper presents a comparison of the microscopic structure and morphometric traits of gustatory and mechanical lingual papillae in newborn and adult frugivorous Egyptian fruit bats (Rousettus aegyptiacus). All of the four types of lingual papillae found in adult animals were observed on the tongue surface in the newborn Egyptian fruit bats. After the birth, the gustatory papillae (fungiform and vallate papillae) were especially well-developed, as their structural characteristics, such as morphology of the epithelium and presence of the taste buds, indicate that they have reached almost complete functional traits. Mechanical papillae, particularly filiform papillae, in newborns are still fetal in character. Keratinization processes in the epithelium of these papillae are not advanced and specific structures, such as elongated processes, are missing. The morphometric analysis of the size of papillae and thickness of the mucosal epithelium showed that a complete development of keratinized structures in Egyptian fruit bats occurs at later stages of postnatal development. [source] QTL for body weight, morphometric traits and stress response in European sea bass Dicentrarchus labraxANIMAL GENETICS, Issue 4 2010C. Massault Summary Natural mating and mass spawning in the European sea bass (Dicentrarchus labrax L., Moronidae, Teleostei) complicate genetic studies and the implementation of selective breeding schemes. We utilized a two-step experimental design for detecting QTL in mass-spawning species: 2122 offspring from natural mating between 57 parents (22 males, 34 females and one missing) phenotyped for body weight, eight morphometric traits and cortisol levels, had been previously assigned to parents based on genotypes of 31 DNA microsatellite markers. Five large full-sib families (five sires and two dams) were selected from the offspring (570 animals), which were genotyped with 67 additional markers. A new genetic map was compiled, specific to our population, but based on the previously published map. QTL mapping was performed with two methods: half-sib regression analysis (paternal and maternal) and variance component analysis accounting for all family relationships. Two significant QTL were found for body weight on linkage group 4 and 6, six significant QTL for morphometric traits on linkage groups 1B, 4, 6, 7, 15 and 23 and three suggestive QTL for stress response on linkage groups 3, 14 and 23. The QTL explained between 8% and 38% of phenotypic variance. The results are the first step towards identifying genes involved in economically important traits like body weight and stress response in European sea bass. [source] Quantitative genetic parameters for growth-related and morphometric traits of hatchery-produced Japanese flounder Paralichthys olivaceus in the wildAQUACULTURE RESEARCH, Issue 12 2007Takahito Shikano Abstract To understand quantitative genetic characteristics of hatchery-produced Japanese flounder in the wild, heritability and genetic correlation of growth-related and morphometric traits were examined in yearling released individuals at a coastal region in northeast Japan. Quantitative genetic parameters were estimated with restricted maximum likelihood following reconstruction of pedigree by a likelihood method using seven microsatellite loci. Estimates of heritability were 0.65 and 0.51 for growth-related traits (body length and the proportion of body length to body depth) and 0.45,0.62 for morphometric traits (vertebral count and dorsal and anal fin ray counts). Genetic correlation was significantly positive (0.61) between dorsal and anal fin ray counts, indicating the possibility of pleiotropic genes or gametic phase disequilibrium for these traits. All the estimates of heritability and genetic correlation in the released individuals were close to those of hatchery-reared juveniles, suggesting that yearling released individuals had similar quantitative genetic characteristics of growth and morphometric traits in the wild to hatchery-reared juveniles. [source] Additive, dominance genetic effects for growth-related traits in common carp, Cyprinus carpio L.AQUACULTURE RESEARCH, Issue 14 2006Cheng-Hui Wang Abstract Additive, dominance genetic effects were analysed for body weight (BW) and seven morphometric traits from three variants of red common carp, Cyprinus carpio var. singuonensis, C. carpio var. wuyuanensis and C. carpio var. color, based on a diallel cross-mating design by using the additive,dominance genetic model. The results indicated that at 8 months of age (juvenile stage), the traits of pre-dorsal height (PDH), pre-dorsal width (PDW) and caudal peduncle height (CPH) were mainly controlled by additive effects; the traits of BW, total length (TL), standard length (SL), head length (HL) and caudal peduncle length (CPL) were mainly controlled by dominance effects. The narrow-sense heritabilities of all traits ranged from 0.000 to 0.556; however, the broad-sense heritabilities ranged from 0.453 to 0.775. At 20 months of age (adult stage), the traits of TL, SL, PDH and CPL were mainly controlled by additive effects, whereas the traits of BW, PDW, HL and CPH were mainly controlled by dominance effects. The narrow-sense heritabilities of all traits ranged from 0.000 to 0.710; the broad-sense heritabilities ranged from 0.629 to 0.934. Through the genetic merit prediction from three parents, it was found that the additive and dominance effects of C. carpio var. color could increase the BW and body length in their progeny, but these two genetic effects of C. carpio var. singuonensis and C. carpio var. wuyuanensis could decrease BW in their progeny. The genetic effects of C. carpio var. wuyuanensis could reduce total length, SL and caudal peduncle length, but increase body height in their progeny. [source] Intraspecific changes in plant morphology, associated with grazing, and effects on litter quality, carbon and nutrient dynamics during decompositionAUSTRAL ECOLOGY, Issue 1 2006MARÍA SEMMARTIN Abstract: Continuous biomass removal by grazing usually changes the resource allocation pattern of plants. These changes often increase resistance to tissue removal and produce individuals with different morphometric traits, such as root to shoot or blade to sheath ratios. Shifts in morphometric traits, in turn, may alter nutrient cycling through changes in the average quality of litter that decomposes in soil. Previous work has shown that Paspalum dilatatum, a native grass from the Pampas grasslands, which inhabits a vast area and supports a wide range of grazing conditions, increases its blade to sheath ratio under continuous grazing with respect to ungrazed conditions. Here, we explored the consequences of these changes apparently associated with grazing regime on litter quality and nutrient dynamics during litter breakdown in soil. We separately analysed litter quality of blades and sheaths of P. dilatatum and determined under controlled conditions their decomposition and nutrient release kinetics over a maximum period of 1 year. We also studied the mineral nitrogen contents in soil amended with each litter type. Blade quality was significantly higher than sheath quality, nitrogen concentrations of blades and sheaths were approximately 1% and 0.6%, respectively, and lignin to nitrogen ratios were approximately 5 and 11 for blades and sheaths, respectively. Phosphorus concentration, however, was similar in both litter types. Blades decomposed 10% faster than sheaths, released 20% more nitrogen and released 15% more phosphorus than sheaths during the last half of the incubation period. During the first 3 months, the soil nitrogen content of litter-amended incubations indicated immobilization with respect to non-amended control; however, later blade incubations mineralized nitrogen, whereas sheath incubations continued immobilizing it. Results revealed that grazing potentially accelerates nutrient cycling during decomposition by increasing the blade to sheath ratio of P. dilatatum individuals, and suggest that this may be an important mechanism underlying grazing impact on nutrient cycling. [source] Wing shape variation in the medium ground finch (Geospiza fortis): an ecomorphological approachBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009BIEKE VANHOOYDONCK Wing design in birds is subject to a suite of interacting selective pressures. As different performance traits are favoured in different ecological settings, a tight link is generally expected between variation in wing morphology and variation in ecological parameters. In the present study, we document aspects of variation in wing morphology in the medium ground finch (Geospiza fortis) on Isla Santa Cruz in the Galápagos. We compare variation in body size, simple morphometric traits (body mass, last primary length, wing length, wing chord, and wing area) and functional traits (wing loading, aspect ratio and wing pointedness) across years, among populations, and between sexes. Functional traits are found to covary across years with differences in climatic conditions, and to covary among populations with differences in habitat structure. In dry years and arid locations, wing aspect ratios are highest and wings are more pointed, consistent with a need for a low cost of transport. In wet years and cluttered habitats, wing loading is lowest and wings are more rounded, suggesting enhanced capabilities for manoeuvrability. Sexes differ in wing loading, with males having lower wing loadings than females. Superior manoeverability might be favoured in males for efficient territory maintenance. Lastly, in contrast to functional traits, we found little consistent inter-annual or inter-site variation in simple morphometric traits. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 129,138. [source] Correlated changes in skeletal muscle connective tissue and flesh texture during starvation and re-feeding in brown trout (Salmo trutta) reared in seawaterJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2004Jérôme Bugeon Abstract Quantitative and qualitative changes to muscle and collagen were analysed following starvation and re-feeding of brown trout (Salmo trutta) reared in seawater. Fish were submitted to starvation for 2 months followed by re-feeding for 1 month and compared with a control group continuously fed. Classical effects of starvation on growth and morphometrics traits were observed with only a partial recovery of these parameters after 1 month of re-feeding. Muscle composition of starved fish was significantly affected (lower dry matter content and higher post-mortem pH) compared with control fish and was partially recovered in re-fed fish compared with continuously fed fish. Muscle structure and composition were affected with thinner muscle fibre and higher connective tissue content for the starved fish but similar thickness of myosepta compared with the control group. No difference was observed after 1 month of re-feeding. Characteristics of the connective tissue were significantly affected by starvation (more high weight molecular collagen form, higher thermal stability of skin collagen). These differences remained significant after the re-feeding period. Starved fish showed also higher mechanical resistance of the raw flesh compared with the control group, but no difference in rheological measurements was observed after 1 month of re-feeding. The changes in texture and their relationships with muscle composition, muscle structure and collagen characteristics are discussed. Copyright © 2004 Society of Chemical Industry [source] | ||||||||||