The epididymis, a key component of the male reproductive system, controls spermatozoa's maturation, fertility, and storage. The objective of this study is to evaluate
the histological, ultrastructural, and immunohistochemical variations in the epididymis
of donkeys that occur throughout the year. During the breeding season (spring) and
nonbreeding seasons (summer, autumn, and winter), 20 epididymis were collected
from adult, clinically healthy donkeys. Compared to non-breeding seasons, the epididymal duct displayed a more active lining epithelium and more sperm in the lumen
during the breeding season. The epithelial height is the lowest and the lumen is the
widest during the breeding season. Furthermore, the epididymal epithelium in the tail
region exhibits undulations with polyps-like projections. The epididymal epithelium is
composed mainly of the principal, basal, and dark cells. Tight junction between adjacent principal cells is more obvious in the breeding season as compared to the nonbreeding seasons. However, intraepithelial lymphocytes, phagocytic, and other
immune cells are more frequent in non-breeding seasons. β-catenin, which is a component of the adherent junctions between adjacent PCs, exhibits more immunoreactivity during the spring. On the other hand, iNOS, an indicator of oxidative stress,
reacts positively during the summer. Additionally, during non-breeding seasons,
autophagy was detected within the epididymal epithelium which may be linked to
stress adaptation. In conclusion, our findings suggest that the histological and ultrastructural characteristics of the epididymal epithelium are more active during spring
compared to other seasons of the year.
 

The adrenal glands are paired abdominal endocrine organs vital to the bird's health.
The present research aimed to provide a comprehensive examination of the histological, ultrastructural, and immunohistochemical investigations of the adrenal gland in
Japanese quail during the post hatching period. The current study was performed on
21 healthy Japanese quail chicks at different post hatching periods. Our results
showed the adrenal gland is surrounded by a connective tissue capsule, which consists of dense collagen fibers containing large blood vessels, chromaffin cells, autonomic ganglia, fibroblasts, and migrating Schwann cells. The zonation of the adrenal
gland is composed of a subcapsular layer, a peripheral zone, and a central zone, which
gets more pronounced with age. At the ultrastructural level, the interrenal cells take
the steroid-secreting cells characters; they have varying amounts of lipid droplets
and abundant mitochondria. Adrenal medullary chromaffin cells showed positive
immunoreactivity to the NSE. With increasing age, the chromaffin tissue's Sox10
immunoreactivity increased. β-catenin is expressed within the plasmalemma and the
cytoplasm of the interrenal and chromaffin cells and its reactivity increased with age,
especially in the chromaffin cells. Our results indicate the adrenal gland undergoes
significant morphological changes during the postnatal life. Overall, the postnatal
period is an important time for the development and maturation of the adrenal
glands.
 

The adrenal glands play a key role in maintaining the physiological balance of birds and
helping them to survive environmental changes. The objective of the present work was to
give a detailed investigation of the histological, ultrastructural, and immunohistochemical
findings of the adrenal gland in Japanese quail during the prehatching phase. The current
study was performed on 45 healthy Japanese quail embryos at different prehatching
periods. Our results showed the primordium of the quail's adrenocortical tissue appeared
at 3 days of incubation as a thickening of the splanchnic mesoderm. The prospective chromaffin cells appeared at 5 days as clusters of cells migrated from the neural crest cells
along the dorsal aorta toward the interrenal tissue. TH immunoreactivity was observed in
the neural crest cells during their migration toward the adrenal primordium. Furthermore,
these TH immunopositive cells were intermingled with the developing interrenal cell cords
that developed from the coelomic epithelium. NSE immunostaining was detected within
the cytoplasm of interrenal cells, chromaffin cells, and ganglion cells. Sox10 is expressed in
chromaffin and ganglion cells with different staining intensities. On the 13th day of prehatching, both interrenal and chromaffin cells were β-catenin immunonegative, but on the
17th day, both cells were immunopositively. Our findings show that during prenatal life,
the adrenal gland undergoes significant morphological changes. Together, the present data
suggest that studying the prenatal development of the adrenal gland in birds is important
for advancing our understanding of this critical organ and its functions.
 

The study was designated to determine some hormonal residues (estradiol, progesterone, and testosterone) in chicken and cattle meat as well as assess the risk of these residues for adult and child consumer health. A total of 92 chicken meat samples were collected from four different chicken farm sales outlets, and 56 cattle meat samples from two brands were collected from markets through 2022 in Assiut City, Egypt. An enzyme-linked immunosorbant assay (ELISA) was used to measure the hormonal residues. Results showed that the estimated daily intake (EDI) of estradiol exceeded acceptable daily intakes (ADIs) in all analyzed samples except four chicken farm meat samples for adults only, which were below 0.05 μg/kg bw, and the hazard index (HI) of estradiol and testosterone residues for adults and children exceeded 1 in all examined samples of the study. The U.S. Food and Drug Administration (FDA) set safe limits for these anabolic hormones to ensure high food quality and quantity for humans, but in Egypt, monitoring and assessment of hormonal residues in food became very urgent as no safe limits have been set till now.

Background and Aim: Several strains of Aspergillus fumigatus produce mycotoxins that affect the health and productivity
of dairy cattle, and their presence in dairy cattle feed is a serious concern. This study aimed to determine the densities of A.
fumigatus and gliotoxin in commercial dairy feed.
Materials and Methods: More than 60 dairy feed samples were examined for fungal contamination, specifically for A.
fumigatus, using phenotypic approaches and DNA sequencing of the internal transcribed spacer (ITS) and β-tubulin regions.
Thin-layer chromatography and high-performance liquid chromatography (HPLC) were used to assess gliotoxin production
in A. fumigatus. Real-time polymerase chain reaction (RT-PCR) was used to investigate the expression of gliZ, which was
responsible for gliotoxin production. High-performance liquid chromatography was used to detect gliotoxin in feed samples.
Results: Aspergillus was the most commonly identified genus (68.3%). Aspergillus fumigatus was isolated from 18.3% of
dairy feed samples. Only four of the 11 A. fumigatus isolates yielded detectable gliotoxins by HPLC. In total, 7/11 (43.Background and Aim: Several strains of Aspergillus fumigatus produce mycotoxins that affect the health and productivity
of dairy cattle, and their presence in dairy cattle feed is a serious concern. This study aimed to determine the densities of A.
fumigatus and gliotoxin in commercial dairy feed.
Materials and Methods: More than 60 dairy feed samples were examined for fungal contamination, specifically for A.
fumigatus, using phenotypic approaches and DNA sequencing of the internal transcribed spacer (ITS) and β-tubulin regions.
Thin-layer chromatography and high-performance liquid chromatography (HPLC) were used to assess gliotoxin production
in A. fumigatus. Real-time polymerase chain reaction (RT-PCR) was used to investigate the expression of gliZ, which was
responsible for gliotoxin production. High-performance liquid chromatography was used to detect gliotoxin in feed samples.
Results: Aspergillus was the most commonly identified genus (68.3%). Aspergillus fumigatus was isolated from 18.3% of
dairy feed samples. Only four of the 11 A. fumigatus isolates yielded detectable gliotoxins by HPLC. In total, 7/11 (43.7%)
feed samples tested had gliotoxin contamination above the threshold known to induce immunosuppressive and apoptotic
effects in vitro. The HPLC-based classification of isolates as high, moderate, or non-producers of gliotoxin was confirmed
by RT-PCR, and the evaluation of gliZ expression levels corroborated this classification.
Conclusion: The identification of A. fumigatus from animal feed greatly depended on ITS and β-tubulin sequencing.
Significant concentrations of gliotoxin were found in dairy cattle feed, and its presence may affect dairy cow productivity
and health. Furthermore, workers face contamination risks when handling and storing animal feed.7%)
feed samples tested had gliotoxin contamination above the threshold known to induce immunosuppressive and apoptotic
effects in vitro. The HPLC-based classification of isolates as high, moderate, or non-producers of gliotoxin was confirmed
by RT-PCR, and the evaluation of gliZ expression levels corroborated this classification.
Conclusion: The identification of A. fumigatus from animal feed greatly depended on ITS and β-tubulin sequencing.
Significant concentrations of gliotoxin were found in dairy cattle feed, and its presence may affect dairy cow productivity
and health. Furthermore, workers face contamination risks when handling and storing animal feed.

This study aimed to evaluate the concentration
of metals such as aluminum (Al), cadmium
(Cd), lead (Pb), barium (Ba), bismuth (Bi), cobalt
(Co), nickel (Ni), chromium (Cr), iron (Fe), copper
(Cu), zinc (Zn), and selenium (Se) in 360 samples of
poultry meat and liver from six brands (A, B, C, D,
E, and F) in Assiut, Egypt; compare these concentrations
with Egyptian and world permissible limits;
and determine their safety for human consumption
according to health risk assessment. Chest, thigh
muscles, and liver were collected randomly from
Assiut city markets, and the concentration of heavy
metals was measured in the central laboratory of
the faculty of agriculture at Assiut University using
inductively coupled plasma mass spectrometry (ICPMS).
All the analyzed samples were positive for the
tested metals and were far below the allowed maximum
permissible limits except for Pb and Fe, which
exceeded the Egyptian Organization for Standardization
(EOS) permissible limits with 33% and 67%,
respectively, as well as Pb and Cd, which exceeded
FAO/WHO permissible limits with 94% and 17%,
respectively. Health risk assessment revealed the
safety and minimum health risk for human consumption
of metal residues in poultry tissues and liver
using estimated daily intake (EDI), target hazardquotient (THQ), hazard index (HI), and target cancer
risk (TR). Even though the THQ and HI values were
significantly lower than 1.0 during our study, heavy
metal monitoring in poultry products and byproducts
is required for human security and safety.

The retina consists of various cell types arranged in eight cell layers and two membranes that originate from the neuroectodermal cells. In this study, the timing of differentiation and distribution of the cellular components and the layers of the rabbit retina are investigated using light and electron microscopy and immunohistochemical techniques. There were 32 rabbit embryos and 12 rabbits used. The rabbit retina begins its prenatal development on the 10th day of gestation in the form of optic cup. The process of neuro- and gliogenesis occurs in several stages: In the first stage, the ganglionic cells are differentiated at the 15th day. The second stage includes the differentiation of Muller, amacrine, and cone cells on the 23rd day. The differentiation of bipolar, horizontal, and rod cells and formation of the inner segments of the photoreceptors consider the late stage that occurs by the 27th and 30th day of gestation. On the first week of age postnatally, the outer segments of the photoreceptors are developed. S100 protein is expressed by the Muller cells and its processes that traverse the retina from the outer to the inner limiting membranes. Calretinin is intensely labeled within the amacrine and displaced amacrine cells. Ganglionic cells exhibited moderate immunoreactivity for calretinin confined to their cytoplasm and dendrites. In conclusion, all stages of neuro- and gliogenesis of the rabbit retina occur during the embryonic period. Then, the retina continues its development postnatally by formation of the photoreceptor outer segments and all layers of the retina become established. RESEARCH HIGHLIGHTS: The aim of this study is to investigate the morphogenesis of the rabbit retina during pre- and postnatal life. The primordia of the retina could be observed in the form of the optic cup. The ganglionic cells are the first cells to differentiate, while the photoreceptor cells are the last. S100 protein is expressed by the Muller cells and its processes. Calretinin is intensely labeled in the amacrine and displaced amacrine cells and moderately expressed in the cytoplasm and dendrites of ganglionic cells.

Bisphenol A (BPA) is a widely used endocrine disruptor that represents a significant risk to male reproductive function. Zinc (Zn) is vital for appropriate development of testes and to guarantee optimal testicular function and spermatogenesis. Our goal was to investigate if zinc oxide (ZnO), either in conventional or nanoformulation, could safeguard adult male rats’ reproductive performance against the damaging effects of BPA. Signaling expression of CYP11A1 and Nrf-2 in the testis, testicular oxidant-antioxidant status, Bax/Bcl-2 apoptotic ratio, and histological examination of various reproductive organs were all evaluated. Twenty-eight adult male albino rats were divided randomly into 4 groups (7 animals each) including the control, BPA, conventional zinc oxide (cZnO)+BPA, and zinc oxide nanoparticles (ZnO-NPs)+BPA groups. The study was extended for 2 successive months. Our findings revealed strong negative effects of BPA on sperm cell characteristics such as sperm motility, viability, concentration and abnormalities. Additionally, BPA reduced serum levels of testosterone, triiodothyronine (T3), and thyroxine (T4). Also, it evoked marked oxidative stress in the testes; elevating malondialdehyde (MDA) and reducing total antioxidant capacity (TAC). BPA significantly downregulated testicular mRNA relative expression levels of CYP11A1 and Nrf-2, compared to control. Testicular apoptosis was also prompted by increasing Bax/ Bcl-2 ratio in testicular tissue. Histopathological findings in the testes, epididymis, prostate gland, and seminal vesicle confirmed the detrimental effects of BPA. Interestingly, cZnO and ZnO-NPs significantly alleviated all negative effects of BPA, but ZnO-NPs performed better. In conclusion, our findings point to ZnO, specifically ZnO-NPs, as a viable treatment for BPA-induced testicular dysfunction.