Veterinary Research Forum

Abstract The amygdala is the nucleus of the brain that is largely responsible for perceiving danger and plays a role in emotion, behavior, control and learning. A small amygdala has been associated to aggression. Horned ewes are expected to be more aggressive and have a smaller amygdala. Both horned and hornless ewes exhibit intraspecific head-butting behavior and both species are at risk for traumatic brain injury. The aim of this study was to investigate the neuronal density, glial cells and blood-brain barrier (BBB) of the amygdala in horned and hornless ewes. Four horned and six hornless ewe heads (age: 16.00 ± 4.00 months) were obtained from the abattoir. The brains were carefully removed and preserved in 10.00% formalin for 5 days. Bilateral amygdalae were sectioned. The samples were stained with Hematoxylin and Eosin, immunohistochemical (glial fibrillary acidic protein) and Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling methods, and the histological structures of the amygdala were examined by light microscopy. The Mann-Whitney U test was used to analyze the data. Neuronal density was estimated to be 143,230 ± 12,540 per mm3 in horned and 152,230 ± 18,430 per mm3 in hornless ewes. Horned subjects had reduced numbers of neurons, damaged BBB and localized inflammatory areas. More apoptotic neurons were observed in horned ewes. Further studies are needed to determine whether these differences in neuronal density, glial cells, and BBB are acquired (due to trauma) or congenital. The results of this study might need further similar studies to be conducted in the future.

Abstract This study investigated carbendazim (CBZ)-induced hepatic dysfunction and the mechanistic pathway regarding the protective effect of melatonin (MEL). Twenty-eight male rats were grouped as follows: Control, CBZ (150 mg kg^-1), MEL (20.00 mg kg^-1), and CBZ + MEL. The experiment was conducted for 60 days. Tissue samples were stained with Hematoxylin and Eosin and immuno-fluorescence methods to examine apoptotic pathway. Also, hepatic enzymes and miR-122 expression were evaluated. The findings indicated that the CBZ group exhibited an increase in degenerated hepatocytes, hyperemia of sinusoids, and leukocyte infiltration, accompanied by elevated levels of aspartate aminotransferase and alanine aminotransferase, as well as up-regulation of miR-122. Also, there was a significant increase in the fluorescence intensities of caspase-3 and Bax in the CBZ group, whereas a substantial reduction in the fluorescence intensity of Bcl-2 was recorded. In contrast, the simultaneous administration of MEL alongside CBZ was shown to be effective in improving histological structure, decreasing levels of aspartate aminotransferase and alanine aminotransferase, reducing the apoptosis index, and modulating the expression of miR-122 in comparison with the CBZ-only group. The increased expression of miR-122 noted in the CBZ group may correlate with an elevation in the immunoreactivity of apoptosis markers and alterations in liver architecture. Additionally, MEL seems to alleviate CBZ-induced hepatotoxicity by down-regulating miR-122 expression, diminishing the fluorescence intensity of caspase-3 and Bax, and enhancing the immunoreactivity of Bcl-2. Collectively, the regulation of miR-122 may serve as a potential mechanism by which MEL confers its protective effects against liver damage induced by CBZ.

Abstract Diabetes mellitus is one of the leading causes of death globally. The development of cellular injuries and impaired energy metabolism are involved in the pathogenesis of diabetes mellitus, leading to severe diabetic complications in different tissues such as the pulmonary tissue. Autophagy is a double-edged sword mechanism required for maintaining cell survival and homeostasis. Any abnormalities in autophagic response can lead to the progression of several diseases. Here, we aimed to assess the effect of diabetic conditions on the autophagic response and exosome secretion in a rat model of type 2 diabetes mellitus. The experimental diabetic group received 45.00 mg kg^-1 streptozocin (STZ) dissolved in 0.10 M sodium citrate. After 4 weeks, we monitored autophagic response and exosome biogenesis in the pulmonary tract using immunohistochemistry (IHC) and Real-time polymerase chain reaction analyses, respectively. Histological examination revealed the interstitial bronchopneumonia indicating enhanced immune cell infiltration into the pulmonary parenchyma. Immunohistochemistry staining displayed an enhanced autophagic response through the induction of microtuble-associated protein light chain 3 (LC3) and protein sequestosome 1 (P62) compared to the control rats. These changes coincided with significant induction of tetraspanin CD63 in STZ-induced diabetic rats relative to control rats. In conclusion, a diabetic condition can increase the autophagic response in pulmonary tissue. The accumulation of P62 in the pulmonary niche exhibits an incomplete autophagic response. The abnormal autophagy response can increase pulmonary cell sensitivity against injuries.

Abstract The study was designed to explore anatomical and histological vasculature changes in the female genital system of camel and serological aspects that might be responsible to maintain thermoregulation. Twenty-four adult female camels were sampled during breeding (November-April) and non-breeding (May-October) season. Blood was collected for estrogen, progesterone and cortisol level estimation. Genital organs were sampled and described after slaughtering. Samples were taken from the ovarian artery (OA), vein (OV) and arterio-venous complex (AVC), for light and scanning electron microscopy. Sections were stained with Hematoxylin and Eosin. (H&E), Masson’s trichrome, Weigert’s elastic and toluidine blue. Temperature and relative humidity were used to calculate stress indicator. Stress indicator was higher in non-breeding season (NBS). Anatomical and histological vasculature (OA, OV, AVC) dynamics were significantly higher in breeding season (BS) especially diameter of left OA. Parameters of OA were positively associated with estrogen level. Collagen, elastic, smooth muscles and mast cells were recorded least in BS compared to NBS. Unique venous structure, intra-mural venules (IMV), was discovered in tunica intima of OA, seen positively and negatively associated with estrogen and cortisol level in BS, respectively. Scanned electron-micrograph exhibited penetration and wrapping of OA by small thinned-walled venules that may form IMV. The AVC was too tightly packed to differentiate due to the collapse of the wall. Hormonal, seasonal, stress indicator and vascular dynamic of female genital system are interlinked and IMV in association with OA and OV may be proposed as the site of counter-current exchange in female reproductive system of the camel.

Abstract Nowadays, the consumption of meat and meat products has been increased with modern manufacturing techniques. Due to the economic value, the likelihood of using unauthorized tissue is possible in meat products. The aim of this study was to apply morphological methods for detection of unauthorized tissues in meat sausage. In this study, a total number of 20 samples of different types of sausages were randomly collected from markets, in north-east of Iran. Each sample was divided into three equal parts and three paraffin-embedded blocks were prepared from each part (180 blocks). Then the sections were stained using Hematoxylin and Eosin, Masson’s trichrome, Periodic acid- Schiff/Alcian blue and Verhoeffe/Van Gieson. A total number of 720 slides were observed using a light microscope. This research showed the use of unauthorized tissues in the sausages which was detected by histological methods. We observed authorized tissues like skeletal muscle fiber (100%), fat tissue (100%) and plant material (97.70%). A wide range of unauthorized tissues were detected including dense connective tissue (6.66%), cartilage (28.30%), bone (8.30%), skin (51.60%), smooth muscle (1.66%) and blood vessels (11.66%). The results of this study confirmed the use of unauthorized tissue in meat sausages in Iran and concluded that the histological methods especially Masson’s trichrome staining are a practical technique for routine assessment of authenticity and quality of sausage to protect the consumers from adulteration.

Abstract In order to conduct this study, eight adult turkey heads were obtained. Pituitary glands were harvested following cranial bones removal and examined morphologically and anatomically as well as topographically. Then, tissue sections were prepared and stained using Hematoxylin and Eosin, Alcian blue, orange G and periodic acid-Schiff staining techniques. The results showed that turkey pituitary gland as a pea-sized structure is located in the ventral part of the cerebrum and composed of adenohypophysis and neurohypophysis parts. Moreover, histological analyses revealed that sinusoids are well-developed at the distal part of the adenohypophysis and irregular masses of endocrine cells exist among them. Distributions of basophilic cells in the distal part of adenohypophysis were significantly higher than those of other endocrine cells, while the acidophilic cells had the lowest distribution. Lower and higher numbers of chromophobe cells were also found compared to those of basophilic and acidophilic cells, respectively. These findings were mostly similar to the other birds’ pituitary gland anatomical and histological features, but there were also differences in cellular elements distributions along with infundibular cavity topography.

Abstract Chlorpyrifos (CPF) is a broad spectrum organophosphate pesticide used for agricultural health purposes. Its principal mechanism of toxicity is the inhibition of acetylcholinesterase. The purpose of present study was to investigate the effects of CPF on testicular tissue and sperm parameters in male rats. Thirty-two healthy male rats were divided into two groups: a CPF-exposed group and a control-sham group. Control-sham group received corn oil (0.20 mL per day). The CPF was administered orally to male rats at 37 mg kg^-1 BW for 45 days to evaluate the reproductive toxicity. In all rats, sampling for histological and sperm analyses was performed on days 5, 15, 30 and 45. The CPF caused a significant (p < 0.05) decrease in sperm count, viability and motility and increased immature sperms and DNA damage in sperm cells. Light microscopic analyses revealed increased arrested spermatogenesis, negative tubular differentiation and repopulation indexes and decreased Leydig cells number. These findings indicate that CPF has adverse effects on sperm cells and reproductive system of male rats.

Abstract In this study the cranial nerves development of H. huso are explained from 1 to 54-days-old (1, 3, 6, 15, 21 and 54 days). Despite all the researches on fish brain, there are no study on nerves evolution on H. huso during their larvae life. For this research 40 samples of larvae H. husowere obtained (from each age, about six samples were selected). The specimens were maintained in fiberglass tank, then histological samples were taken from tissues and stained with hematoxylin and eosin for general histological studies using light microscope. According to the results, on 1 and 3-days-old, no nerve was observed. The terminal nerve and their dendrites were observed around the nasal cavity and the axons projected to different areas in forebrain especially around olfactory bulb diffusely, on 6-day-old fish. Also, olfactory, optic, oculomotor, trochlear, trigeminal, lateral line and vagus nerves were detected on 6-day-old fish, however two parts of lateral line nerve were separated on 54-day-old. Three nerves, profundus, facial and octaval were observed on 54-day-old, however, up to this age, epiphysial nerve was not observed.

Abstract Unilateral orchidectomy (UO) is required when further breeding potential is important. It is sometimes necessary to remove a single testis in a matured stallion for therapeutic reasons. In this study, twelve donkeys were used to evaluate three techniques of unilateral castration, histological and morphological changes on the remaining testis. Results of the study showed that each of the surgical techniques used had its advantages and disadvantages in comparison with the other two techniques. Therefore the selection among the three techniques depends on the surgeon preferences and the environment in which the unilateral orchidectomy is performed. The volume of the remaining testis recorded at the end of the study was significantly greater than that estimated at the start of the study (p < 0.05). The percentage of sperm motility obtained from the remaining testis was significantly decreased (p < 0.05). Histological examination of the testis in open surgery (group I) (where the scrotum was left opened) revealed severe hemorrhages, edema and fibrosis. The testis showed degenerative changes in the seminiferous tubules and interstitial orchitis. Histological examination of the testes removed using a closed technique, (in groups II and III) where the scrotum wound was sutured, revealed hyperplasia of spermatogenic series and Leydig cells. In conclusion, unilateral orchidectomy had compensatory effects on the weight and volume of remaining testis. Adverse effects on sperm motility and viability can affect the fertility of the animal.

Abstract Rabbitfish is economically valuable teleost species which lives in shallow coastal waters. Two species of rabbit fish have been recognized in southern sea of Iran (Persian gulf) as namely Siganus sutor and Siganus javus. In the current study, in order to investigate the histology of the annular ligament of the S. javus’ eye, the prepared sections of the eyes of twelve healthy specimens were studied under light microscope. The results revealed that annular ligament is a crescent shape structure which is situated between the scleral stroma anteriorly and the iris posteriorly. It contains a vascularized, amorphous and granular matrix with fibers of dense connective tissue; high glycogen content and melanin pigments.

Abstract Histological and histochemical studies on the pancreas of goose (Anser albifrons) were carried out using special staining and light microscope. The pancreas in goose is serous tubuloacinar gland having exocrine and endocrine part. Smooth muscle fibres were absent in capsule of pancreas. Acinar cells have bizonal shape. Intralobular ducts, Interlobular and main excretory ducts were present within parenchyma. The intralobular ducts were lined with a simple cuboidal epithelium reach interlobular ducts lined with low columnar epithelium. The main excretory ducts were lined by simple to stratified columnar epithelium. The glands inside the connective tissue of the ducts and basophilic staining on the apical surface of pancreatic duct system were found from the interlobular ducts to the main excretory ducts. The endocrine part was consisted of various shapes and sizes of alpha and beta islets. Mixed islets were not observed in the goose pancreas. Parasympathetic ganglia were observed in the exocrine pancreas. No significant differences were noted between males and females.