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Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecosistemas y Recursos Agropecuarios is the property of Universidad Juarez Autonoma de Tabasco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Clearing and staining techniques have been present since 1897, However, their use in anatomical studies of adult micromammals has been limited. When using such techniques in combination with allometric method, it is possible to study articulated skeletons of micromammals, instead of relying only on the skulls, which is important in morphologically complicated groups as the rodents. Research involving multivariate allometric analysis of postcranial skeleton of rodents has been limited and confined to specific items. In this study, we analyzed and compared the morphometry of the skeleton of Neotomodon alstoni with that of Meriones unguiculatus, Phodopus campbelli and Rattus norvegicus. We applied the double staining and clearing technique in order to determine the morphometric relation between these rodents using sixty skeletal characters. We found that three species share two common correlations and one isometric, with apparent similarities between the morphometry patterns of P campbelli with the ossification pattern described for the related species Mesocricetus auratus. The differences in allometric growth could represent differences in the development stages according to the type of life history for each species. In this analysis we confirmed that both the preparation technique and morphometric analysis method, are simple yet verifiable tools for anatomical and morphological studies. Our results reflect the conditions of ontogenetic development derived from the heterochrony pattern for each species, representing the evolutionary history for this group. Therefore, as this approach continues to be discussed, ongoing research is warranted. [ABSTRACT FROM AUTHOR]

Copyright of Revista U.D.C.A Actualidad & Divulgación Científica is the property of Universidad de Ciencias Aplicadas y Ambientales U.D.C.A and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Boletín Científico Centro de Museos de Historia Natural is the property of Universidad de Caldas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Caldasia is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Ciencia y Tecnología Agropecuaria is the property of Agrosavia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The results of the inclusion of alfalfa hay on emus diet were determined, as a plain trial to analyze the field practice of using it as a roughage source similar to other ratites diets. Materials and methods. The treatments consisted of two diets, without (diet 1) or with (diet 2) alfalfa hay inclusion. Twenty emus, with 38.4 weeks of mean age, were distributed in two treatments and housed in a semi-intensive system with ad libitum feed and water. The body weight was assessed weekly over 13 weeks. After 91 days of trial, the emus were slaughtered and the carcass yield and gastrointestinal allometry were measured. Results. Cumulative weight gain was lower (p<0.05) by intake diet 2 than diet 1, 2.12 and 2.08 kg, at 11 and 12 weeks after the start of the trial, respectively. Further, abdominal and visceral fat deposition in the emus fed with diet 2 was 0.77 and 0.63% lower (p<0.05), respectively. The inclusion of alfalfa hay increased gizzard and intestine relative weight (p<0.05) and intestine relative length (p<0.05), however, cecum allometry wasn’t affected (p>0.05). Conclusions. Alfalfa hay can negatively compromise the growth and fat deposition of emus when it is added to the finisher feed, and alter the allometry of the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

In this study, we investigated sexual dimorphism in body size (snout-vent length) and morphological traits (head, neck, trunk, and limbs) in a population of skinks belonging to a newly discovered species of genus Plestiodon. In addition, we determined the allometric trajectories of body traits that showed sexual dimorphism and discussed their importance in the expression of the sexual differences found. A Student's t-test was performed to detect different significant in the SVL and a multivariate approach was followed to investigate sexual dimorphism in the other characters examined. Reduced major axis regression (SMA) were used to determine the corresponding allometric trajectories. No sexual dimorphism was detected in the snout-vent length and body mass. The length and width of the head, the length of the neck and the length of the hind limbs were greater in males than in females; by contrast, the opposite pattern was found in the case of trunk length. Isometric relationships were detected, as well as positive and negative allometric relationships between the traits analyzed. However, only sexual dimorphism in the head width was affected by their growth trajectories. [ABSTRACT FROM AUTHOR]

Copyright of Investigación Bibliotecológica is the property of UNAM, Centro Universitario de Investigaciones Bibliotecologicas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mathematical models for biomass and carbon prediction are currently options that facilitate and improves the calculation of the climate change mitigation capacity of an ecosystem, by generating essential information to establish national carbon storage indices. The objective of the study was to evaluate the biomass of the different tree elements (leaves, branches, stem, root) through destructive and indirect methods, to construct predictive biomass and carbon models. The models were developed using the method of ordinary least squares, using the normal diameter as the regressor variable. These equations explained more than 94 % of the variability observed in biomass or carbon, with errors of estimates below 5 %. The stem contributed with 57.4 % to the tree total biomass, and the leaves contributed with 5 %. The carbon fraction was very similar among the woody components (branches-stem-root), which varied from 44.9 % to 45.7 % and in the leaves it reached 40.7 %. [ABSTRACT FROM AUTHOR]

Introduction: Clypeaster europacificus is a species of sand dollar found from 0 to 200 m in the Gulf of California. Objective: Describe the morphology and relative growth in the test of C. europacificus. Methods: We measured 1 846 museum specimens of C. europacificus (N = 1 846) and analyzed growth pattern in 32 specimens from Baja California Sur, Mexico (64 m depth). We studied five variables: major radius (R) (independent variable), minor radius (r), length of anterior petal (LP), total test area (A) and dry weight (P). Results: The petaloid cover area and the outline of the test are the important taxonomic characters for C. europacificus: they range from almost round in small specimens (≤ 3 cm in radius) to wavy, emphasizing a pentagonal outline, in larger organisms (≥ 3.1 cm in radius). Conclusions: There is negative allometric growth in the relationships R vs. r, R vs. A, and R vs. P; while the relationship R vs. LP has positive allometric growth. [ABSTRACT FROM AUTHOR]

For Brycon moorei, morphometry data in early stages of development is non-existent. The objective was to establish the main allometric relationships in the early stages of B. moorei. 12 meristic variables were analyzed in an experimental time ranging from hatching to 15 days post-hatching. In the larval vitelline stage (LV), it was recorded on average: total length (TL) of 4.74 ± 0.05 mm; standard length (EL) of 4.21 ± 0.07 mm; snout length (SnL) 0.3 ± 0.01; eye diameter (ED) 0.37 ± 0.007 mm; head length (HL) 1.02 ± 0.04 mm; head height (HH) 0.88 ± 0.069 mm; body height (BH) 1.26 ± 0.01 mm; snout-pectoral fin length (SnPF) 1.35 ± 0.034; absence of pelvic, anal and dorsal fins and the weight was 1.8 ± 0.2 mg. In juvenile stage (J), the measures were: LT of 25.66 ± 0.64 mm; LE of 21.49 ± 0.63 mm; SnL of 1.69 ± 0.059 mm; 1.71 ± 0.048 mm ED; HL 6.33 ± 0.21 mm; HH of 4.89 ± 0.47 mm; BH of 6.13 ± 0.17 mm; SnPF of 6.48 ± 0.19 mm; SnPeF of 10.83 ± 0.28 mm; SnDF of 11.16 ± 0.33 mm; Sn-AF of 3.68 ± 0.34 mm; the weight was 221.6 ± 15.84 mg. For the LV, the number of pre-anal myomers was 28.65 ± 4.7; the post-anal was 23.85 ± 4.27, with a total of 52.47 ± 8.34; for J the myomers were not visible. This information is essential for ecological and productive purposes in B. moorei. [ABSTRACT FROM AUTHOR]

Length-weight relationship and condition factor (K) have been used as a fish biological descriptor, because they provide information about growth, reproduction, and welfare. Therefore, these parameters can be used in the assessments of fish populations inhabiting aquatic systems affected by different levels of intervention. The main objective of this study was the depiction and description of the length-weight relationship, condition factor and diet of Bryconops giacopinii in six sites at Serranía La Lindosa over one annual cycle (dry and wet seasons). Fish (n = 333) were measured, weighted, and the stomach was removed to identify prey items. Fish displayed a positive allometric growth during both seasons, without differences in the condition factor during the seasonal change. On the other hand, 17 prey items were identified; most of them terrestrial arthropods. The frequency and occurrence of these items did not follow a temporal or spatial pattern. B. giacopinii displayed a generalist diet, with a high consumption rate of terrestrial insects. The obtained results show the strong relationships between this species and the riparian forest, proving the importance of this biological corridors to the maintenance of the aquatic community and its conservation. This information contributes to the biological knowledge of this species out commercial interest and can be used to compare other populations in other basis. B. giacopinii is a species with an important ecological role. Therefore, research of its relationship with the ecosystem could be of great relevance and necessity. [ABSTRACT FROM AUTHOR]

Antecedentes: el desarrollo del tracto gastro intestinal (TGI) es de crucial importancia para optimizar la digestión del alimento y la disponibilidad de nutrientes suficientes para el animal. Factores físicos como la forma y granulometría del alimento determinan el comportamiento de consumo del ave, debido principalmente a la facilidad de aprehensión de la partícula y a la tasa de pasaje del alimento, lo cual puede impactar el rendimiento productivo y el desarrollo del TGI. Objetivo: evaluar el efecto de la forma y granulometría del alimento sobre el rendimiento productivo y el desarrollo de órganos digestivos. Métodos: el estudio fue desarrollado en el centro de validación de Iluma Alliance-Colombia con aval del comité de ética (CEIUVA-044, April 7 2022). 1840 pollos machos de la línea Ross 308 AP fueron alojados en corrales de piso y asignados a uno de tres tratamientos (T1 alimento en harina fina (707 µm), T2 alimento en harina gruesa (1012 µm) y T3 alimento peletizado) bajo un arreglo de bloques completos al azar; los días 21 y 42 se evaluó el consumo y la ganancia de peso; además se sacrificaron 10 aves por tratamiento para cuantificar la longitud, el peso relativo (peso del órgano vacío/peso del animal) y pH de los diferentes órganos digestivos. Los datos obtenidos fueron analizados bajo un modelo lineal mixto y las diferencias entre tratamientos fueron determinadas mediante prueba de Tukey con una significancia del 5 %. Resultados: las aves que recibieron alimento peletizado tuvieron una mejor tasa de conversión alimenticia al final del ciclo experimental en comparación a las aves que recibieron alimento en harina. Sin embargo, el pH a lo largo del TGI fue significativamente menor y el peso relativo de los órganos digestivos (proventrículo, molleja, duodeno, yeyuno e íleon) incrementó significativamente en las aves alimentadas con dietas en forma de harina gruesa en comparación a la dieta peletizada y harina fina. Conclusión: la forma del alimento (harina o pellet) y el tamaño de partícula tiene un efecto significativo sobre el pH y el desarrollo de los órganos digestivos lo cual a su vez impacta la salud del TGI y el rendimiento productivo de las aves. [ABSTRACT FROM AUTHOR]

In this work both the biomass and carbon present in a vegetative cover from a silvopastoral system were quantified. The system, composed of Hyparrhenia rufa and Guazuma ulmifolia, was established naturally in Balzar, Guayas province of Ecuador. By using a destructive method and a random sampling in nested plots both the arboreous and underground biomass of average-sized trees were measured as well as the necromass and herbaceous vegetation. Models were developed in order to estimate the volume and the biomass of the whole tree and its components (trunk, roots, branches and leaves). The arboreous biomass was estimated in 16;45 Mg=ha (8;23 MgC=ha), whereas the herbaceous vegetation and the necromass were 1;4 and 1;9 Mg=ha (0;7 and 0;95 MgC=ha), respectively. The models predict the biomass and the volume in dependence of the diameter with less than 3% of error and R² values higher than 96%. In addition, information regarding factors that influence the expansion of biomass were generated. [ABSTRACT FROM AUTHOR]

Drimys winteri is an abundant tree species in the natural forests of Chile, growing as secondary forest of high ecological and economical importance between 41° and 43° S. The height-diameter relationship is key for estimating volume, biomass and for understanding ecological features of tree species. However, there is a lack of research about allometric relationships for this species. We aim at modeling the height-diameter relationship of D. winteri by nonlinear mixed-effects models. We used an extensive sample of trees between Llanquihue and Chiloé Provinces in southern Chile. We analyzed several models, and afterwards, assessed to which parameters allocate the random effects. Finally, we modeled these random effects as a function of stand-level variables (e.g., density, basal area). The proposed model has a biologically consistent behavior; its parameters are efficiently estimated because we considered the hierarchical structure of the data and took into account the effect of competition (represented by density and diameter of the mean basal area tree) and site quality (represented by the mean annual increment in dominant height) of the forests where the trees are growing. Our findings showed that the height-diameter allometry of D. winteri varies depending on competition and site productivity, two key variables for silvicultural management. [ABSTRACT FROM AUTHOR]

Copyright of Comechingonia: Revista de Arqueología is the property of Comechingonia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The order Ciconiiformes include wading bird species of sizes from medium to high, with body growth dynamic that can be analyzed to enlighten micro evolutionary trends. Egrets and herons (family Ardeidae) evolved from a common ancestor, but there are differences in adult body shapes and their evolution has been suggested to be based on heterochronic processes. However, previous researches on growth have focused only in lineal dimension, and alometric changes have not been studied. In the current paper I described changes in body proportions during growth in seven ardeid species and analyzed body growth under a phylogenetic point of view, to identify the primitive morphology pattern among genus Butorides and Nycticorax. For this purpose, I calculated bill/ tarsus rate in 353 nestlings, measured between 1998 and 2006, and assessed their changes with age and body weight. All species showed marked differences in proportion changes extension between hatching and an analogous growth moment, except Bubulcus that grows almost isometrically. Alometric changes during growth and at hatch, generate a differential growth that produced the different adult morphologies expressed among egrets and herons. The general trends were toward a slight increase in the middle of the growth period up to a lowering to almost the same initial proportions. Growth in the first life stages tends to be more isometric and differences get higher latter in growth. The hypothesis of Nycticorax as peramorphic morfotype is more parsimonious with changes trends in the group, resulting in a relative extremities extension with positive alometry in bill and tarsus in all species. This hypothesis is consistent with a gradual hipermorphosis that reaches a maximum expression in Ardea. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, several phytosanitary problems have been identified, causing deterioration of the mangrove forests of the gulf of Urabá and, consequently affecting the communities that use their products. Especially the presence of tumors in Rhizophora mangle trees was detected several years ago. In order to evaluate its relationship with the structure and anatomy of R. mangle trees, 24 circular plots of 500 m2 were established, at the mouth of the Atrato river, a site with a high incidence of these tumors in mangroves, and three plots in the cove of Rionegro, where have not been registered tumors so far. Diameters and heights of trees with DBH greater than 2.5 cm were measured, and their vigor was evaluated. Most plots located at the mouth of the Atrato River, showed a higher percentage of infection (only 4 of them showed low infection percentage). In the logistic model, for any combination of DAP and vigor, the presence of galls in trees was more likely than absence, and the probability of finding an infected tree increased, as DAP increased, and its vigor was more unfavorable. The overall vigor effect was statistically significant, however, the contrasts between upper categories (2-4) did no show significant differences. The proportion of infected trees was high (> 75%) in categories greater than 10 cm of DBH, showing the high level of spread of the infection in the Atrato river delta. The diameter distributions retain the positive relationship found with the logistic model between the diameter of the trees and the presence of galls. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate the leaf area of eight yacon morphotypes by simple linear regression analysis. The research was conducted between 2014 and 2015, in the Andean Roots and Tubers Program of the National University of Cajamarca, Peru (7° 10' 00" S, 78° 30'00" W, 2650 masl). One hundred leaves of basal, middle and terminal strata of each morphotype in full bloom, were taken. The outlines of fresh leaves were drawn on paper and the blade's length (L) and greater width (W), was measured. The measured blade's area (or actual) was determined with digital planimeter. With the measured area (dependent variable) and the values of length, width, squared length, squared width, length x width and length/width (as independent variables), the regression analysis for each morphotype, was performed. In all morphotypes, except in two, the best equations to estimate the leaf area, were those in which intervened the product of L x W. The equation which allowed to estimate the leaf area of the morphotypes together was A= 20.41 + 0.4167 (L x W) (r2 = 0.89). Petiole area of the studied morphotypes represented 15% of the total leaf area. [ABSTRACT FROM AUTHOR]

A non-destructive method to estimate leaf area of "valerian" (Valeriana pilosa Ruiz & Pav.) in wild species, using the length and width of the largest leaf blade was found. A sample of 564 leaves (of 53 flowering plants) of different age and position on the plant was taken. Silhouettes of fresh leaves were drawn on paper and in them the length and width of the sheet was measured. The measured area (or real area) of the sheet was determined with a planimeter. With the measured area (dependent variable) and the values of length, width, squared length, squared width and length/ width (independent variables), a correlation and regression analysis were performed to find the equation of greater adjustment (higher r and r²). The equation that best estimate leaf area in this species in the wild is A = 0.6161 (L x W) + 2.4039 (r² = 0.94, SD: 10.58). [ABSTRACT FROM AUTHOR]

Copyright of CES Medicina Veterinaria & Zootecnica is the property of Universidad CES and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geometric morphometric methods and main component analysis were used to quantify patterns of ontogenetic change in the external contour of head and body of seventeen larval samples of Pseudis paradoxa. With digital pictures and using the method of trusses, we determined the Cartesian coordinates in twelve homologous landmarks and described 25 anatomical homologous inter landmarks variables (distances). The analysis allowed us to assess the relative importance of each variable in the description of the changes of shape and growth, and the calculation of allometric coefficients. In the studied larvae of Pseudis paradoxa, it was observed that in the ontogenetic development, the body presents reductions of the size and shape in the front, and lengthening or widening towards the middle part. Changes in body shape were stronger in samples with exposed limbs, where small areas with high growth were determined. Likewise, divergences are evident in the shape in samples of the species, coming from some locations. This can determine the importance of the method, as a tool to address the taxonomic problem of species, as in the case of Pseudis paradoxa, which has wide zoogeographical distribution. [ABSTRACT FROM AUTHOR]

In the community of "Mariano de Matamoros", Tlaxco, Tlaxcala, 25 trees of Pinus patula Schl. et Cham., were selected and aboveground biomass and carbon contents were determined to fit the model Y=b*Xk, using diameter at breast height as an independent variable (X). A sample of each component (bole, branches and leaves) was obtained from each tree and both sample and total component fresh weight were determined in the field. The samples were taken to the laboratory to be dried and weighted so that, each tree's biomass could be estimated, using the dry weight to fresh weight ratios of the samples. To determinate carbon contents for the different components, samples were taken from 25 trees and analyzed in the laboratory to obtain carbon content for leaves of 52,21%, branches 49,47%, bole 49,26% and an average concentration 50,31%. To estimate aboveground biomass the equation B = 0,0357 * DN2.6916 was fitted and to estimate carbon content the equation fitted was CC = 0,021 * DN2.6451, with a coefficient of determination for both equations of 0,98. [ABSTRACT FROM AUTHOR]

The estimation of the leaf area in the agricultural sciences is fundamental because it is a factor that is involved in different physiological processes. Therefore, it is necessary to make estimates from allometric models that consider the assumptions and statistical criteria needed to extract or infer useful information from them. Numerous studies have proposed models in different cultivars to estimate the leaf area, however, many do not critically evaluate the suitability of the assumptions of the model, therefore, they end up being biased models. In consideration of the above, this study describes a methodology that allows the non-destructive estimation of the leaf area through statistical strategies applied to tropical crops that is demonstrated with practical examples developed in Stevia rebaudiana. [ABSTRACT FROM AUTHOR]