Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title><jats:p>To observe developmental changes in the ovarian tissue structure and distribution characteristics of oestrogen receptors (ERs) in the ovaries of Huanghuai goats at different ages, we selected healthy Huanghuai goats ewes and divided them into five groups (i.e. 3‐, 30‐, 60‐, 90‐ and 120‐day‐old groups), with 10 animals in each group. The serum was separated after blood collection through the jugular vein, and the contents of oestrogen (E) and progesterone (P) in the serum of Huanghuai goats at each age were determined. Three goats were randomly selected from each group and sacrificed after anaesthesia, and the ovarian tissue was quickly obtained and placed in 4% paraformaldehyde fixative to prepare the tissue sections. Using HE, oestrogen receptors were immunohistochemically stained and observed. These results showed many primordial follicles and occasional secondary follicles in the ovaries of 3‐day‐old Huanghuai goats. Ovarian reticular structures were observed in 30‐day‐old ovarian medulla, with occasional near‐mature growing follicles. Mature follicles and corpus luteum were occasionally detected in 60‐day‐old ovarian cortex. The 90–120‐day‐old ovarian cortices contained growing and mature follicles, and the number of mature follicles and corpora lutea increased, implying a significant luteal involution period. The E and P contents in the 120‐day‐old group were significantly higher than those in the 3‐, 30‐, 60‐ and 90‐day‐old groups. The levels of ERα and ERβ in the 3‐ and 30‐day‐old groups were mainly distributed in the granulosa cells of ovarian reproductive epithelial cells, primordial follicles, atretic follicles, and primary and secondary follicles. The ERα and ERβ levels of the 60‐, 90‐ and 120‐day‐old groups were also distributed in the granulosa cells and luteal cells of mature follicles, especially in the 120‐day‐old endometrial cells of mature follicles, where ERβ was distributed significantly. The overall expression of ERβ in the ovary was higher than that of ERα. The results of this study provide basic data on the ovarian development and the specific expression of ERs and PRs in the ovaries of Huanghuai white goats, which play an important role in ovarian development and precocity.</jats:p>

<jats:title>Abstract</jats:title><jats:p>This study aimed to describe the gestational and morphological aspects of the fetuses and their respective umbilical cords from two pregnant wild boars (<jats:italic>Sus scrofa</jats:italic>). Morphological descriptions were provided for 23 fetuses and the gestational ages were estimated through fetal characteristics and formula application. The specimens were fixed in 10% formalin for subsequent macroscopic and microscopic examination. Histological characterization was performed using haematoxylin–eosin (H&amp;E), Masson's trichrome (MT) and Verhöeff's staining techniques. The wild boar fetuses exhibited an estimated gestational age of 55 days (in the larger uterus) and 45 days (in the smaller uterus). They displayed well‐developed features consistent with domestic pig fetuses, except for the presence of five pairs of mammae. Additionally, the umbilical cord consisted of two arteries, one vein, an allantoic duct, and a vitelline duct (the latter two identified only microscopically), located in the juxtafetal, intermediate and juxtaplacental portions. The arteries and veins were comprised of endothelium, smooth muscle and collagen fibres, with no elastic fibres observed in the vessel walls. The allantoic duct was lined with simple cuboidal epithelium, while the vitelline duct featured a simple squamous epithelium. In conclusion, the morphological characteristics observed in the examined structures align with the expected patterns for species of the <jats:italic>Suidae</jats:italic> family. Furthermore, these findings contribute substantially to the morphological characterization of the wild boar, yielding valuable insights into the fetal morphology and the structure of the umbilical cord.</jats:p>

<jats:title>Abstract</jats:title><jats:p>There are different strains of laboratory mouse used in many different fields. These strains differ anatomically. In order to determine these anatomical differences, shape analysis was conducted according to species. CD‐1, C57bl/6 and Balb‐c strains were preferred to study these differences. Forty‐eight adult mouse strains belonging to these strains were utilized. The bones were photographed and geometric morphometry was applied to these photographs. Principal Component Analysis was applied to determine shape variations. In Principal component 1 for <jats:italic>cranium</jats:italic>, CD‐1 and C57bl/6 strain groups showed different shape variations, while Balb‐c strain group showed similar shape variations to the other strain groups. Principal Component 1 for the <jats:italic>mandible</jats:italic> separated the CD‐1 and C57bl/6 strain groups in terms of shape variation. Principal Component 2 explained most of the variation between the C57bl/6 and CD‐1 lineage groups. In PC1 for <jats:italic>molars</jats:italic>, the CD‐1 group showed a different shape variation from the other groups. Mahalanobis distances and Procrustes distances were measured using Canonical variance analysis to explain the differences between the lineage groups. These measurements were statistically significant. For <jats:italic>cranium</jats:italic>, in canonical variate 1, CD‐1 group of mouse and Balb‐c group of mouse were separated from each other. In canonical variate 2, C57bl/6 group of mouse were separated from the other groups. For <jats:italic>mandible</jats:italic>, Balb‐c group of mouse in canonical variate 1 and CD‐1 group of mouse in canonical variate 2 were separated from the other groups. For <jats:italic>molars</jats:italic>, CD‐1 group of mouse in canonical variate 1 and Balb‐c group of mouse in canonical variate 2 were separated from the other groups. It was thought that these anatomical differences could be caused by genotypic factors as well as dietary differences and many different habits that would affect the way their muscles work.</jats:p>

<jats:title>Abstract</jats:title><jats:p>This is the first study to describe the subtypes, number and distribution of mast cells (MC) in cat tongue by histochemical and immunohistochemical methods. Six male adult felines' tongue tissue samples consist of the study's material. Samples were fixed in 10% formaldehyde. MC number and distribution in the feline tongue were assessed using toluidine blue. Also, sections taken from blocks were stained in alcian blue/safranin O (AB/SO) combined dyes to determine the MC subtypes. The Streptavidin biotin complex method using anti‐chymase and anti‐tryptase primary antibodies was used for immunohistochemistry. Metachromatic MCs were mainly observed in the lamina propria close to the multilayered keratinized stratified squamous epithelium. The high number of MCs in this region may be because the dorsal surface of the tongue plays an essential role in the defence system of tongue tissue and, thus, of the body as a whole. Additionally, the number of MCs stained with AB (+) (1.7 ± 0.08) in the feline tongue was statistically higher than those with SO (+) (0.18 ± 0.02). This might be interpreted as an indication that MC heterogeneity may be due not only to their staining properties but also to their localization. It is also conceivable that the high histamine content may be a factor in this. Tryptase‐positive MCs were found in the loose connective tissue around blood vessels, between the glands, as solitary cells, or in groups of several cells. Chymase‐positive MCs were observed more individually rather than in groups. Moreover, chymase‐positive MCs were detected to be located in the filiform papillae subepithelial and in the blood vessels' immediate vicinity. Animals often lick themselves to clean themselves and promote healing. For this reason, it is very important to protect the tongue, which is in direct contact with the external environment, against foreign agents. Considering both the functional and protective properties of the tongue, we concluded that MCs may play a role in oral cavity immunity and protective effect.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Although the order Rodentia does not present a high risk of extinction compared to mammals as a whole, several families demonstrate high levels of threat and/or data deficiency, therefore highlighting the need for targeted research and the application of ecological and reproductive data to the development of conservation actions. The order Rodentia, the largest among mammals, includes 9 families, and the family Cricetidae is the most diverse of the Brazilian rodents. In Brazil, 12 of the 16 genera of <jats:italic>Oecomys</jats:italic> are found. <jats:italic>Oecomys bicolor</jats:italic> is known in Brazil as the ‘arboreal rat’ and is, found in dry, deciduous and tropical forests. The mean body weight of <jats:italic>Oecomys bicolor</jats:italic> was 35.8 g and the gonadal, tubular and epithelial somatic indexes were, 0.53%, 0.47% and 0.37%, respectively. Seminiferous tubules volume density was 89.72% and the mitotic and meiotic indexes corresponded to 8.59 and 2.45 cells, respectively, and the yield of spermatogenesis was 23.83 cells. The intertubular compartment represented 10.28% of the testis parenchyma and around 5% of the interstitial space was occupied by Leydig cells, whose number per gram of testis was 11.10 × 10<jats:sup>7</jats:sup> cells. By evaluating the biometric and histomorphometric characteristics of the testis, there is evidence that this species has a high investment in reproduction. Due to the high contribution of the seminiferous epithelium and the intertubular compartment in this species, compared to the others of the same family, it is possible to infer that the species <jats:italic>Oecomys bicolor</jats:italic> has a promiscuous reproductive behaviour.</jats:p>

<jats:title>Abstract</jats:title><jats:p>A comprehensive light and ultrastructural examination of the cornea in Domestic Pigs (<jats:italic>Sus scrofa domesticus</jats:italic>) revealed four distinct layers: the anterior epithelium, corneal stroma, Descemet's membrane and endothelium. Although Bowman's layer was not distinctly identified through histology, histochemical analysis indicated the presence of a rudimentary Bowman's layer, possibly vestigial from evolution. Scanning electron microscopy of the outer corneal surface unveiled two cell types, characterized by micro‐projections, with light cells exhibiting shorter, thicker projections compared to dark cells. Examination of the inner surface via scanning electron microscopy demonstrated an endothelial layer devoid of cilia and microvilli, yet faint round to oval elevations were observed, potentially representing cell nuclei. Transmission electron microscopy unveiled that basal cells of the anterior epithelium closely adhered to the basement membrane, featuring half desmosomes along the basal surface. These basal cells extensively interconnected through interdigitations and a few desmosomes. The superficial cell layer consisted of a few rows of closely attached flat cells, forming a leak‐proof layer with zona occludens. The outermost cells of this layer displayed fine projections to enhance the surface area, facilitating tear film distribution. At lower magnification, Transmission electron microscopy of the corneal stroma revealed alternating light and dark bands, with light bands representing transverse sections of collagen fibril lamellae and dark bands corresponding to longitudinal or oblique sections. Spindle‐shaped keratocytes (fibroblasts) were identified as the primary stromal cells, intermingled between the lamellae, and featured long processes in close contact with neighbouring keratocytes. Overall, the histomorphology of the pig cornea resembles that of the human cornea except indistinct Bowman's membrane. This detailed understanding of the normal corneal structure in pigs hold great significance for biomedical research, providing a valuable reference for studies involving this animal model.</jats:p>