Differences In Morphometric Measurements Research Articles

Morphologic, morphometric and contour shape variations of sagittal otoliths of Lepidorhombus spp. in the Aegean Sea.

Otoliths are calcareous anatomical structures in the inner ear of fishes, and they can be used in the discrimination of fish species and stocks due to their species-specific shape. Sagittal otoliths in the Lepidorhombus whiffiagonis and Lepidorhombus boscii, two flatfish species of the same genus distributed in the Aegean Sea, were compared using morphology, morphometry and contour shape analyses. Blind and eyed side otoliths of Lepidorhombus species were evaluated separately due to their morphological features and statistical differences in morphometric measurements (p < 0.05). Four analysis groups were formed: blind side otolith of L. whiffiagonis, eyed side otolith of L. whiffiagonis, blind side otolith of L. boscii and eyed side otolith of L. boscii. Morphometric differences in otolith shape were performed by canonical discriminant analysis, and the first discriminant axis explained 97.4% (Wilks λ=0.270) of the variance between the groups, and the second axis explained 2.3% (Wilks λ=0.620). Classification success between Lepidorhombus species based on CDA is 100%, and the overall CDA classification score between groups is 76.5%. The wavelet functions obtained in the contour analysis showed high variability in the anterior, posterior-dorsal, antero-dorsal and ventral regions of the otoliths among these four analysis groups. Consequently, it is thought that this study will contribute to the taxonomic classification of fish with the morphological and morphometric differences in the blind and eyed side otoliths and the analyses made with the high discrimination success obtained in Lepidorhombus species.

A Comparative Histomorphological and Histochemical Study of the Ventriculus between Iraqi Adult Geese (Anser anser) and Guinea fowls (Numidia meleagris)

The present study aimed to describe and compare the histomorphological and histochemical structures to ventriculus in Goose(Anser anser) and Guinea fowls (Numidia meleagris). The work was carried out on twenty apparently clinically healthy birds obtained from a supplier in Baghdad city. They were allocated in two equal groups of each type of bird. The two groups were utilized for histological and histochemical investigations of their ventriculus organ. After anesthesia and killing birds, their abdominal cavity was dissected, their ventriculus was identified and proper specimens from its walls were prepared. The samples designated for histochemical staining were fixed in a solution of bruin's fixative, while the others for general histological examination were fixed in (10%) neutral buffered formalin. After processing, the sections were stained with (2.5 PH) Alcian- PAS combination, periodic acid Schiff, Masson Trichrome, and Hematoxylin and Eosin stains. This study elucidates that the microscopic construct of the ventriculus was similar for the two species. The ventriculus consists of three tunicates (serosa, muscularis, and mucosa), whereas the submucosa is absent. The wall showed some significant differences in morphometric measurements. The mucosa of the ventriculus is coated with a thick layer of cuticles organized as a wavy clear pink line parallel to the mucosal surface and mucosal folds. The simple cuboidal-columnar epithelium covered the mucosa, which showed many folds. The proprial glands (simple tubular type) are lined by simple cuboidal epithelium, which opens into the crypts between the folds. A well-developed muscular comprised of smooth muscle fibers as two layers of inner circular and outer longitudinal. Serosa is composed of loose connective tissue coated by mesothelium. The Mean thickness of Cuticle, length of folds, mucosa and muscular in goose were significantly higher than that in guinea fowl; these differences may be due to variation in their diet. PAS and AB-PAS combined (2.5-PH) stains, cuticle layer, epithelium lining, and gastric glands showed a positive reaction with these stains. This study aimed to Study the normal histomorphological histochemical and structure of Gizzard in two avian species, local male guinea fowl (Numidia meleagris) and male geese (Anser anser). Also aimed to Comparative histomorphological, histomorphometric measurements and histochemical study of the Gizzard of two different local male avian species (Guinea fowl and geese). Keywords: Histomorphological, Histochemical, Ventriculus, Guinea fowls, Geese

Age and Gender Differences in Morphometric Measurements of Brain Stem Using Magnetic Resonance Imaging in Healthy Indian Adults

Background: Morphometric changes in the brain stem can be an early indicator for ongoing physiological or pathological changes. Establishing age- and gender-matched linear morphometric values of the brain stem serves as a useful reference for comparison. Aims and Objectives: This study aimed to determine normal measurements of brain stem structures in healthy Indian adults and to establish age and gender differences in brain stem measurements if any. Materials and Methods: This hospital-based cross-sectional study was conducted from November 2020 to January 2021 on patients referred to the department of radiodiagnosis for magnetic resonance imaging (MRI) of the brain. Baseline data and linear midsagittal measurements on MRI were recorded. Results: A total of 142 patients were included in the study. The average measurements for midbrain, pons, medulla at pontomedullary (PM), and medulla at cervicomedullary junction are 1.67 ± 0.17 cm (mean ± standard deviation [SD]), 2.16 ± 0.18 cm (mean ± SD), 1.39 ± 0.16 cm (mean ± SD), and 1.08 ± 0.13 cm (mean ± SD), respectively. Significant reduction in brain stem measurements at all levels with P &lt; 0.05 were recorded with increase in age except for the medulla at the PM junction which remained constant. There was no significant difference in brain stem measurements between males and females. Conclusion: Normal reference value for AP diameter of the brain stem in healthy Indian adults showed statistically significant reduction at various levels with advancing age. There were no statistically significant gender differences in sagittal diameter of the midbrain, pons, and medulla.

Occurrence of the genusMonhystrella (Nematoda: Monhysteridae) in continental aquatic reservoirs and first description of the male of Monhystrella hoogewijsi

AbstractThe order Monhysterida is highly important to freshwater environments, containing a number of genera noted for their ability to endure extreme environmental conditions, such as those found in semi‐arid regions. The genus Monhystrella is often cited in references to these regions. The present study was performed in six reservoirs in a semi‐arid region of Brazil, employing collection and identification techniques commonly used for the phylum Nematoda. Sixteen genera pertaining to the phylum were detected, although only Monhystrella was found in all the reservoirs, with a monospecific population of Monhystrella hoogewijsi identified in Olivedos Reservoir. The present study contains the first record of this genus and species in Brazil, as well as the first‐ever description of the male of the species. The main morphometric variations were a longer tail and smaller amphidial fovea of females from the Brazilian semi‐arid region. The differences in morphometric measurements and the description of the male specimen expand current descriptions and levels of knowledge regarding this species.

Investigating host plant association, calling activity, and sexual dimorphism in Indian Gryllacropsis sp. (Orthoptera: Anostostomatidae).

Both sexes of Indian weta Gryllacropsis sp. communicate acoustically. Females lack an external ovipositor making it difficult to differentiate between the sexes in the field. There is limited ecological information on the species as it is found high up on the trunks of evergreen trees, well camouflaged, and active only at night. The present study was conducted to gain ecological information on this little known yet intriguing species. We tested the hypotheses that (a) calling activity of Indian weta is uniformly distributed throughout the year and (b) there is no difference in morphometric measurements between the sexes. The study was conducted in Bhagwan Mahavir Wildlife Sanctuary and Mollem National Park, Goa, India. Visual scanning of tree trunks followed by vegetation sampling, psychoacoustic sampling, and morphometric analyses was carried out. Resource selection function values, obtained for a total of 52 tree species from 1984 individuals, were less than 0.1 for all plant species indicating no preference by the wetas. Peak calling activity was observed in the month of November (Rayleigh's test, Z = 7.90, p < .01). Discriminant function analysis on morphometric characters of males and females (Wilk's λ = 0.32 approx. F (4, 21) = 11.24 p < .0001, classification accuracy = 96.15%) provided clear distinction between males and females. Contribution of body weight was significant (standardized canonical discriminant function coefficients = +1) and could be used for identification of sexes in the field. These polyphagous insects provide insights on understanding ecological specialization due to host plant association, signal evolution, and mating behavior.

Stock delineation of the long-whiskered catfish, Sperata aor (Hamilton 1822), from River Ganga by using morphometrics

Long-term isolation of populations and interbreeding can lead to morphometric variations among fish populations. This study was conducted with the objective to delineate stock structure of Sperata aor on the basis of morphometric characters, using truss network of the fish body. In total, 407 S. aor samples were collected from the four sampling locations of the Ganga River, viz. Narora, Kanpur, Varanasi and Bhagalpur. In total, 28 truss distance measurements were created by joining 13 morphometric landmarks on the fish body. MANCOVA showed significant (P&amp;lt;0.001) morphological variance among the sampling locations for the target fish species. Univariate ANOVA showed significant (P&amp;lt;0.001) differences in each of the morphometric measurements among the fish from different sampling locations. Wilk’s lambda test of canonical discriminant function analysis showed significant (P&amp;lt;0.001) differences in morphometric measurements of the fish from all sampling locations. Discriminant function analysis using Jackknife (leave-one-out) cross-validation classification showed 87.5% correct classification of the individuals into their original populations. Mantel test showed an overall good correlation between the genetic and morphometric datasets in the selected fish species. The results of this study can be employed in formulating stock-specific management strategies for S. aor from River Ganga.

Classical and geometric morphometric methods reveal differences between specimens of Varroa destructor (Mesostigmata: Varroidae) from seven provinces of Iran

Varroa destructor Anderson & Truman is the most serious pest of honey bee colonies all over the world. Its specimens were assessed by morphometric and geometric morphometric methods using six morphometric traits including body length and width, length and width of the right metapodal shield, length of epigynal and the anal shield for classical morphometrics and six landmarks in ventral surface of mite's body, in seven provinces including Ardabil, Markazi, Qom, Qazvin, Alborz, North Khorasan, and Semnan. Twenty and ten individuals were used for morphometric and geometric morphometric studies, respectively. The ventral surface of each mite slide was prepared and used Digimizer and Tps package software for morphometric and geometric morphometric measurements, respectively. Data were analyzed with Past software. Furthermore, principal component analysis (PCA) was used for both two methods. In addition, Cluster analysis was used to categorize specimens of provinces. The results demonstrated significantly morphometric and geometric morphometric (or shape and size) differences among the specimens of provinces. Qazvin and Ardabil were located in one group with the PCA and Cluster analysis in the classical morphometric method and Alborz mite's dimensions showed a significant difference in morphometric measurements with other provinces. However, in the geometric morphometric method, Ardabil, Markazi, North Khorasan, and Semnan specimens were located in another group. The difference in distribution can be related to geographical factors and methods of measurement.

Siberian Ibex (Capra sibirica) Neonatal Kid Survival and Morphometric Measurements in Ikh Nart Nature Reserve, Mongolia

Understanding the factors infl uencing survival of ungulate neonates facilitates successful management programs, particularly as they relate to population dynamics and adaptive species management. However, kid survival of near threatened Siberian ibex (Capra sibirica) remains poorly understood. During 2005-2013, we captured and collared 21 ibex kids in Ikh Nart Nature Reserve in southeastern Mongolia, to monitor their survival and cause-specifi c mortality. We found no diff erences in morphometric measurements between male and female kids, except body mass being males weighing more than females. A total of 11 mortalities were documented and predations by red foxes (n=5, Vulpes vulpes) and grey wolf (n=1, Canis lupus) was the leading cause of the mortalities. Known fate models indicate the monthly survival of kids best explained by body mass and fi rst month of life (April-May + weight). Monthly survival estimates ranged from 0.077 (95% CI = 0.60-0.88) in April-May to 0.97 (95% CI = 0.90-0.99) in June-March, with an annual survival rate of 0.45 (95% CI = 0.24-0.68). We found little support for the hypotheses that body mass or birth date infl uenced survival; however, our small sample size limited the power of the analyses. Overall, our results indicated that predation and other factors led to high kid mortality during the period shortly after birth.

A multiple lines of evidence approach for the ecological risk assessment of an accidental bitumen release from a steam assisted gravity drainage (SAGD) well in the Athabasca oil sands region

To assess the ecological impacts of two independent accidental bitumen releases from two steam assisted gravity drainage (SAGD) wells in the Athabasca oil sands region, a multiple lines of evidence (LOE) approach was developed. Following the release in 2010, action was taken to minimize environmental impact, including the selective removal of the most highly impacted vegetation and the use of oil socks to minimize possible runoff. An ecological risk assessment (ERA) was then conducted based on reported concentrations of bitumen related contaminants in soil, vegetation, and water. Results of biological assessments conducted at the site were also included in the risk characterization. Overall, the conclusion of the ERA was that the likelihood of long-term adverse health effects to ecological receptors in the area was negligible. To provide evidence for this conclusion, a small mammal sampling plan targeting Southern red-back voles (Myodes gapperi) was carried out at two sites and two relevant reference areas. Voles were readily collected at all locations and no statistically significant differences in morphometric measurements (i.e., body mass, length, foot length, and adjusted liver weight) were found between animals collected from impact zones of varying levels of coverage. Additionally, no trends corresponding with bitumen coverage were observed with respect to metal body burden in voles for metals that were previously identified in the source bitumen. Hepatic ethoxyresorufin-O-deethylase (EROD) activity was statistically significantly elevated in voles collected from the high impact zones of sites compared to those collected from the reference areas, a finding that is indicative of continued exposure to contaminants. However, this increase in EROD was not correlated with any observable adverse population-wide biological outcomes. Therefore the biological sampling program supported the conclusion of the initial ERA and supported the hypothesis of no significant long-term population-wide ecological impact of the accidental bitumen releases.

VARIAÇÃO BIOMÉTRICA DE DIÁSPOROS DE BURITI (&lt;i&gt;Mauritia flexuosa&lt;/i&gt; L.f. – ARECACEAE) EM VEREDAS EM DIFERENTES ESTÁGIOS DE CONSERVAÇÃO

http://dx.doi.org/10.5902/1980509816583As veredas são fitofisionomias do bioma Cerrado, onde, no estrato arbóreo, predomina a palmeira arbórea Mauritia flexuosa L.f. - buriti, espécie considerada recurso-chave para muitos animais, que a utilizam como moradia e fonte alimentar, e também pelo próprio homem, que usa suas folhas e frutos como matéria-prima e alimento. Apesar de ocorrerem em ambientes protegidos pela legislação ambiental, ações antrópicas nas veredas têm afetado as populações do buriti, por meio da diminuição do número de indivíduos ocasionada por desmatamento, assoreamento e drenagem dessas áreas. O objetivo desse trabalho foi avaliar a morfometria de frutos e sementes de buriti oriundos de seis veredas em diferentes estágios de conservação, situadas na Área de Proteção Ambiental do Rio Pandeiros (norte de Minas Gerais). Foram amostrados, no total, 1800 frutos e sementes, que foram mensurados em comprimento, largura, espessura e peso. Para detectar diferenças das medidas morfométricas dos frutos e das sementes entre as áreas de coleta foi feita a análise de variância. Foram observadas variações nas medidas morfométricas de frutos e sementes entre as áreas de estudo, sendo que 87,5% das maiores médias ocorreram em áreas com menores intervenções antrópicas. Esse fato, possivelmente, está relacionado aos impactos ocorridos nas veredas, além das variações genéticas que podem incidir sobre os indivíduos.

Regional variation in body size of the cheetah (Acinonyx jubatus)

Body size affects almost every aspect of the biology of a species, with considerable intraspecific variation. Cheetahs (Acinonyx jubatus) reportedly vary in body size across their geographical range. However, because morphometric measurements were not taken in a standardized manner, it is impossible to rule out differences in measurement protocols as the cause. Our study differed from previous ones in that we made use of a standardized methodology for taking morphometric measurements in cheetahs. Free-ranging cheetahs in Namibia were shorter (3.5–4.1%) and slimmer (4.0–7.0%) than those in neighboring Botswana. Cheetah density was more than 3 times higher and home-range sizes were more than 3 times smaller in Botswana compared to Namibia. This suggests that variation in resource availability may be the main driver of the fine-scale spatial differences in morphometric measurements. Overall, our study promotes the use of standardized protocols for measuring morphological traits in free-ranging animals.

Sexual Differentiation in the Male and Female Mouse from Days 0 to 21: A Detailed and Novel Morphometric Description

We hypothesized that a significant portion of sexual differentiation of mouse external genitalia occurs postnatally. To establish a baseline of normal development to which genital abnormalities could be compared, we determined morphometric measurements and morphological descriptions of the postnatal period of sexual differentiation in mice from birth to 21 days postnatally. The external genitalia of male and female CD-1® mice were serially sectioned for histological staining. Mice were studied by age group, including ages 0 to 1, 2 to 3, 4 to 5, 10 and 21 days. Three-dimensional reconstructions were created to visually compare differences. Morphometric measurements were made of the distal mouse external genitalia and compared across age groups, and between males and females. The morphology of male and female mouse external genitalia is similar at 0 to 1 days but undergoes dramatic changes during 21 days. The changes include the development of mesenchymal extensions, which in males form the male urogenital mating protuberance and erectile bodies, as well as comparable structures in females. Differences in morphometric measurements in homologous males and females became pronounced during 0 to 21 days, serving as a baseline for recognizing the genesis of malformations of the mouse external genitalia. Male and female mouse external genitalia are similar morphologically and morphometrically at birth but achieve dramatic differences by age 21 days, suggesting that a significant portion of sexual differentiation in the mouse occurs after birth. We described these changes using novel, accurate morphometric measurements and 3-dimensional reconstruction. These results will be useful for studying abnormal sexual development of the mouse external genitalia.

Histopathological examination of chronic laminitis in Kaimanawa feral horses of New Zealand

AIMS: To investigate the prevalence, histopathological and histomorphometric presentation of chronic laminitis in a population of Kaimanawa feral horses. METHODS: Following the capture and euthanasia of feral horses from the Kaimanawa Ranges of New Zealand, the left forefoot of 28 stallions and 28 mares aged between 6 and 12 years were removed and processed for histology. Sections of lamellar samples from each horse were examined using light microscopy. The presence of laminitis was assessed and the histopathological lesions were described. Horses were grouped by histological diagnosis into laminitic and non-laminitic groups and histomorphometric analysis was conducted and compared between groups. The parameters examined were total length of primary epidermal lamellae (PEL), keratinised length of PEL, and the length of secondary epidermal lamellae (SEL) at the abaxial end and axial end of each PEL. RESULTS: Of the horses examined, 25 (45%) were diagnosed with chronic laminitis. The most prevalent histopathological features were the presence of excessive cap horn, and multi-branched and attenuated SEL. Histomorphometric assessment of the lamellar architecture revealed no difference in morphometric measurements between the normal and laminitic groups for any parameter measured (p>0.05). CONCLUSIONS: The current study found a high prevalence of laminitis in feral Kaimanawa horses. The reason for this in the Kaimanawa population is not known. Histomorphometric analysis may not be a good indicator of chronic laminitis in feral horses. CLINICAL RELEVANCE: It is an important finding that the feral horse lifestyle in the environment of the Kaimanawa Ranges in New Zealand offers no protection against foot disease. The finding suggests that horses are vulnerable to laminitis whether in domestic care or in a feral habitat.

Research Article: Comparative morphometric analysis of captive vs. wild African lion (Panthera leo) skulls

Abstract Panthera leo are a carnivorous species with significant bone growth occurring from gestation to 3–4 yrs. In captivity, species are not necessarily subject to all stresses influencing bone development that would otherwise result in the wild. The factors fully influencing bone development in the wild are unknown. The purpose of this study was to determine if differences in morphometric measurements are present between wild and captive populations of lions, specifically in the regions of mastication. Twenty-one different measurements were taken on fifty-seven skulls. Morphometric measurements of museum specimens from the wild were compared with specimens obtained from zoos and other captive environments. Results from analysis indicate significant differences between captive and wild specimens. The majority of these variances were in the regions of mastication; areas influenced by external stress. Wild specimens possess greater morphometric dimensions in regions of stress.