The lung of birds is the most complex and efficient gas exchanger in the air‐breathing vertebrates. A total number of 27 normal Japanese quail embryos during the pre‐hatching period were used. The current work aimed to investigate the histomorphological, histochemical and ultrastructural changes of the lung at different stages of development using light and electron microscopy. The results showed that the respiratory primordium was observed on the 2nd embryonic day (ED) as a ventral out‐pouching of the primitive foregut into the surrounding mesenchyme. The first evidence of the lung buds appeared on the 3rd ED. On the 4th ED, the buds increased in size. In addition, the secondary bronchi budded from the epithelial lining of the primary bronchus into the surrounding mesenchyme. On the 6th ED, the number of the secondary bronchi increased and began to give rise small tubules (parabronchi). On the 7th …

Various biomaterials have been evaluated to enhance bone formation in critical-sized bone defects; however, the ideal scaffold is still missing. The objective of this study was to investigate the in vitro and in vivo regenerative capacity of graphitic carbon nitride (g-C₃N₄) and graphene oxide (GO) nanomaterials to stimulate critical-sized bone defect regeneration. The in vitro cytotoxicity and hemocompatibility of g-C₃N₄ and GO were evaluated, and their potential to induce the in vitro osteogenesis of human fetal osteoblast (hFOB) cells was assessed using qPCR. Then, bone defect in femoral condyles was created in rabbits and left empty as control or filled with either g-C₃N₄ or GO. The osteogenesis of the different implanted scaffolds was evaluated after 4, 8, and 12 weeks of surgery using X-ray, computed tomography (CT), macro/microscopic examinations, and qPCR analysis of osteocalcin (OC) and osteopontin (OP) expressions. Both materials displayed good cell viability and hemocompatibility with enhanced collagen type-I (Col-I), OC, and OP expressions of the hFOB cells. Compared to the control group, the bone healing process in g-C₃N₄ and GO groups was promoted in vivo. Moreover, complete healing of the bone defect was observed radiologically and grossly in g-C₃N₄ implanted group. Additionally, g-C3N4 implanted group showed higher percentages of osteoid tissue, mature collagen, biodegradation, and expressions of OC and OP. In conclusion, our results revealed that g-C₃N₄ and GO nanomaterials could induce osteogenesis in critical-sized bone defects.

The vagina is part of the genitalia and constitutes part of the birth canal. Sperm
is deposited into vagina, and it acts in transport of sperm. Pregnancy is a complex
process involving different physiological changes in the body associated
with hormonal and metabolic alterations that control maternal and fetal
demands. During pregnancy, neuroendocrine cells in rabbit vagina are considered
part of the diffuse neuroendocrine system observed throughout the body.
Giant neuroendocrine cells in rabbit vagina during pregnancy have not been
observed previously. This study detected the presence of giant neuroendocrine
cells in the vagina of the pregnant rabbit. The presence of these cells was demonstrated
with the use of different histological techniques, including hematoxylin
and eosin, PAS, combined Alcian blue-PAS, Crossmon's trichrome, and the
Grimelius silver method. Giant neuroendocrine cells were observed in latepregnancy
intraepithelial sites and on the lamina propria. These cells were characterized
by vacuolated basophilic cytoplasm with PAS- and PAS-AB-positive
granules. Moreover, neuroendocrine cells exhibited an argyrophilic character.
Immunohistochemically, neuroendocrine cells in rabbit vagina during pregnancy
demonstrated positive immunoreactivity to neuron-specific enolase (NSE) with
different intensities, mild immunoreactivity to the vascular endothelial growth
factor (VEGF), and negative immunoreactivity to CD68

Endometrial remolding and angiogenesis are critical events that occur during pregnancy in order to establish uteroplacental vascular
communication. This study investigated the role of uterine telocytes (TCs) in pregnancy. We analyzed the distribution of TCs and
morphological changes in the endometrium of the gravid rabbit uterus at different stages of pregnancy: after ovulation, pre-implantation (day
7), post-implantation (days 8 and 9), and mid-pregnancy (day 14) and late (days 21–28) pregnancy. TCs gradually increased with the
progression of pregnancy. They had distinctive telopodes (TPs) and podoms, with intranucleolar chromatin. The TCs established contact with
decidual cells, growing a glandular epithelium, blood vessels, and immune cells, such as lymphocytes, neutrophils, and macrophages. The
TCs underwent morphological changes at the post-implantation phase. They acquired thick and voluminous TPs, formed an extensive threedimensional
(3D) labyrinth at mid-pregnancy, and exhibited irregular-shaped nuclei and a dilated rough endoplasmic reticulum at late
pregnancy. They also acquired a convoluted contour-formed complex network. Scanning electron microscopy (SEM) showed an extensive 3D
network in the endometrium, forming a condensed sheath at late pregnancy. Transmission electron microscopy and SEM detected
fenestrated TPs, and TCs were identified by CD34 and vascular endothelial growth factor expression. TCs also expressed matrix
metalloproteinase-9 and transforming growth factor beta-1. Results suggested that TCs might play an essential role in maternal placenta
formation, especially decidualization, regulation of uterine gland development, and neovascularization of maternal uterine blood vessels.

Abstract
Background: Organic egg is among the most common organic foods offered for sale in Egyptian markets in recent years, and consumers buy them at a higher price because they believe organic eggs are safer and have superior nutritional value than conventional eggs.
Aim: The present work aimed to monitor antimicrobial residues in brown table eggs, whether conventional or organic type, in Aswan governorate markets and assessed their physical and chemical quality and their public health hazards.
Methods: Brown table egg samples (n = 400 total) were randomly selected in the present study, in which they represented two equal groups (n = 200 each) including conventional eggs and organic eggs. Eggs were collected from different retail stores in the Aswan governorate, Egypt. Egg samples were subjected to thorough physical and chemical quality evaluation as well as an assessment of antimicrobial residues.
Results: The results reported that organic eggs were cleaner and had a better odor, less blood, and meat spots, but smaller with more shell cracks than conventional eggs. Chemical analysis of some nutrient contents in the egg yolk revealed significantly higher nutritive values of organic eggs than that of conventional ones as the organic eggs contain significantly higher levels of vitamin A and vitamin D/D3 and significantly lower values of cholesterol, calcium, magnesium, and zinc than those in conventional eggs. Disc diffusion assay has been used for monitoring antimicrobial residues in egg samples. The results have shown that all examined organic eggs were free from antimicrobial residues, while 12% and 8% of conventional egg yolk and white were positive for antimicrobial residues, respectively.
Conclusion: The study concludes the higher nutritive value of organic eggs compared with the conventional type because of their significantly higher contents of vitamins A and D and their significantly lower contents of cholesterol. Moreover, organic eggs were free from antimicrobial residues which maximizes their public health benefits.

This experiment was conducted to evaluate the effect of adding Origanum majorana (OM)
powder to domestic pigeon diets on growth performance, feeding and drinking behaviour, blood
hematology, blood biochemical parameters, blood inflammatory and oxidative markers, carcass
characteristics, the weights of lymphoid organs, and and intestinal cecal, and bursa of Fabricius
histology. A random distribution of fifty-four unsexed pigeon squabs (30 days old, average body
weight; 321 g  7.5) into three groups was done. The first group was fed the grower basal diet
without adding OM powder, while OM powder was added at levels of 0.5 and 1% to the basal
diets of the second and third groups, respectively. The changes in growth performance parameters
and feeding and drinking behavior under OM powder’s effect were insignificant. However, the
lymphoid organs (spleen and thymus) significantly increased in weight (p < 0.05) in the OM-fed
groups. Moreover, blood examination showed positive responses to OM powder in terms of blood
cell counts (RBCs andWBCs), and the values of hemoglobin, hematocrit, mean corpuscular volume,
lymphocyte numbers, levels of globulin, and glutathione peroxidase enzyme were significantly
increased. The numbers of heterophils, the ratio of heterophil to lymphocyte, malondialdehyde levels
were reduced (p < 0.05). Histomorphometry examination revealed increases in intestinal villi height,
cecal thickness, and bursal follicle area and number. These results indicated that adding OM powder
to the pigeon diet may improve their immunity, increase their antioxidant status, and correct some
hematological disorders.