Anatomy of the Laboratory Rat.

5.3.1 Male Reproductive System

Heat stress is one of the most challenging environmental stresses affecting domestic animal production, particularly commercial poultry, subsequently causing severe yearly economic losses. Heat stress, a major source of oxidative stress, stimulates mitochondrial oxidative stress and cell dysfunction, leading to cell damage and apoptosis. Cell survival under stress conditions needs urgent response mechanisms and the consequent effective reinitiation of cell functions following stress mitigation. Exposure of cells to heat-stress conditions induces molecules that are ready for mediating cell death and survival signals, and for supporting the cell's tolerance and/or recovery from damage. Heat-shock proteins (HSPs) confer cell protection against heat stress via different mechanisms, including developing thermotolerance, modulating apoptotic and antiapoptotic signaling pathways, and regulating cellular redox conditions. These functions mainly depend on the capacity of HSPs to work as molecular chaperones and to inhibit the aggregation of non-native and misfolded proteins. This review sheds light on the key factors in heat-shock responses for protection against cell damage induced by heat stress in chicken.

https://www.mdpi.com/2076-2615/10/12/2407/pdf

Modulation of Heat-Shock Proteins Mediates Chicken Cell Survival against Thermal Stress

The current study aimed to describe the anatomical features of the tongues of two micro-mammals common in the Egyptian fauna; the Nile grass rat (Arvicathis niloticus), and the Egyptian long-eared hedgehog (Hemiechinus auritus). The tongues of five adult individuals of each species were excised and processed histologically, histochemically, and morphometrically. Statistical analysis comparing the relative tongue length in both species showed that there was a significant difference, which may correlate with the difference in feeding preferences. Grossly, the Nile grass rat has a dorsal lingual prominence with bifurcated apex while, the long-eared hedgehog has a median slight elevation with rounded apex. Numerous forms of mechanical and gustatory papillae are scattered along the lingual dorsal epithelium. The histochemical detection of keratin by Holland's trichrome stain showed an intense expression in the case of A. niloticus and mild expression in H. auritus. The framework of the tongue (entoglossum) is supported by either a core of cartilage in H. auritus or bone in A. niloticus which incorporated in the lingual root. The lingual glands also showed marked variation, the Nile grass rat exhibit dense populations of mucous-secreting glands and lesser populations of serous-secreting glands, the contrary is true in H. auritus. In conclusion, the micro and macro-anatomical features of the tongues of both species showed adaptive changes to accommodate the feeding lifestyle. Such type of studies using mammals from different phylogenetic traits and almost have different feeding preferences provide answers to many research questions related to tongue evolution among mammalian vertebrates.

Descriptive studies on the tongue of two micro-mammals inhabiting the Egyptian fauna; the Nile grass rat (Arvicanthis niloticus) and the Egyptian long-eared hedgehog (Hemiechinus auritus).

The aim of this study was to characterise the tongue in wild-type rats using several microscopic techniques. Warsaw Wild Captive Pisula Stryjek (WWCPS) rats belong to a lineage of wild-caught rats. The study was carried out on tongues of 15 male and 15 female WWCPS rats. Histological, histochemical and ultrastructural studies were carried out. There were no significant differences between the male and female WWCPS rat tongues. There was a median groove approximately 1 cm long in the apex of the tongue that faded caudally. The intermolar prominence was clearly marked in the distal part of the lingual body. Lingual mechanical papillae located on the surface of the tongue formed four subtypes based on their shape: small filiform papillae, giant filiform papillae, thin elongated filiform papillae and wide filiform papillae. Gustatory papillae formed the second group of papillae and were divided into bud-shaped fungiform papillae, a single vallate papilla surrounded by an incomplete papillary groove and foliate papillae, which were a well-formed and composed of several pairs of folds divided by longitudinal grooves. In the posterior lingual glands (mucoserous and serous), acidic sulphated mucin-secreting cells gave a strong AB pH 2.5 positive reaction, and a positive reaction with the AB pH 1.0 stain for acidic carboxylated mucin. Double AB/PAS staining showed the presence of the majority of mucous cells with predominant of acidic mucins. Positive PAS staining showed the presence of neutral mucin. HDI staining demonstrated a weak positive reaction within Weber’s glands of the WWCPS rat tongue.

/pdf/biological-aspects-of-the-tongue-morphology-of-wild-captive-2mruvaov5b.pdf

Biological aspects of the tongue morphology of wild-captive WWCPS rats: a histological, histochemical and ultrastructural study

The hedgehog tongue is a tactile and taste organ which carries out various functions. Detailed functional and morphological studies are required to clearly define the relationship of the hedgehog tongue with taste, food palatability, mastication and swallowing of food, as well as the production of sounds. The aim of this study was to determine the relationship between the morphological characteristics of the European hedgehog tongue and the lifestyle of this animal, as well as to compare findings with the results of studies on other vertebrates. Gross and micro-anatomical light and scanning electron microscopy studies revealed that the hedgehog tongue could be divided in three areas, namely the apex, body and root. A keratinized stratified squamous epithelium, which was smooth on the ventral surface but bore four types of papillae on the dorsal surface, lined the tongue. Three types of these papillae were found to have gustatory functions and to express their activity in close relation with the salivary glands. These simple conical filiform papillae were situated caudally and distributed one after the other without a break. The dome-shaped fungiform papillae on the apex, with the highest distribution rate on the apex edge, were small, but those on the body and root were large. The three circular vallate papillae were arranged in a triangular shape. The foliate papillae with a few tiny projections, found in a shallow furrow, were situated between the root and the body. Most of the nerve fibers observed in different sections of the tongue tissue were of the unmyelinated type, confirming that the main task of the hedgehog tongue was its gustatory function.

Morphological study of the European hedgehog (Erinaceus europaeus) tongue by SEM and LM

To develop a technique for the injection of local anaesthetic into the spinal canal of broiler chickens by first determining the ideal location for needle placement based on anatomy and histology, ...

Development and evaluation of a technique for spinal anaesthesia in broiler chickens.

Lidocaine is used for epidural and spinal anesthesia in various animal species. The ideal drug for epidural and spinal anesthesia should have a long effective duration in addition to a fast onset of action, and adequate analgesia and muscle relaxation. Despite the delayed onset of action, bupivacaine provides a longer duration of anesthesia than lidocaine. The purpose of this study was to compare the onset to effect and duration of action between lidocaine and bupivacaine for spinal anesthesia in broiler chickens. Thirty-two, 8-week-old, female Ross broiler chickens were randomly divided into 4 groups of 8: 1) 2 mg/kg lidocaine (L); 2) 0.1 mg/kg bupivacaine (B0.1); 3) 0.25 mg/kg bupivacaine (B0.25); and 4) 0.5 mg/kg bupivacaine (B0.5). After aseptic preparation, a 23-gauge spinal needle was inserted into the synsacrococcygeal space of the chickens with correct needle placement confirmed by a sudden loss of resistance. Spinal anesthesia was performed with the aforementioned doses of lidocaine and bupivacaine. The respiratory rate and cloacal temperature were measured every 10 minutes in each chicken until the anesthetic effect was no longer present. The onset to effect and the duration of action were calculated for each bird based on the pinch test at predetermined time intervals. The results are demonstrated as mean ± SD. The onset of action for bupivacaine (9 ± 1.41, 4.33 ± 1.15, and 3.33 ± 1.23 minutes in B0.1, B0.25, and B0.5 groups, respectively) was significantly delayed compared with that of lidocaine (1.37 ± 0.52 minutes). The duration of action of B0.5 (54 ± 6.08 minutes) was significantly longer than that of any other group (17.87 ± 3.18, 11 ± 1.41, and 18 ± 4.36 min in L, B0.1, and B0.25 groups, respectively). The results showed that a spinal injection of 0.5 mg/kg bupivacaine produces approximately 55 minutes of spinal anesthesia in these broiler chickens, which is much longer than the 18 minutes of anesthesia provided by 2 mg/kg lidocaine. Considering the various disease conditions that affect the cloacal area of birds, one can use each of these anesthetic drugs for either short-term or long-term spinal anesthesia in chickens and possibly other avian species.

https://bioone.org/journals/journal-of-avian-medicine-and-surgery/volume-35/issue-1/1082-6742-35.1.60/Comparison-of-Anesthetic-Efficacy-of-Lidocaine-and-Bupivacaine-in-Spinal/10.1647/1082-6742-35.1.60.pdf

Comparison of Anesthetic Efficacy of Lidocaine and Bupivacaine in Spinal Anesthesia in Chickens

Background: Paclitaxel (PTX), a chemotherapeutic agent, and monosodium glutamate (MSG) have oxidative effects on testicular tissue.
Objective: In this study, the effects of MSG administration on the exacerbation of testicular tissue alterations related to PTX treatment were evaluated.
Materials and Methods: MSG (30 & 60 mg/kg i.p.) was administrated to six groups (n = 8/each) of adult mice before or after PTX treatment: control, PTX-treated, MSG30 + PTX, MSG60 + PTX, PTX + MSG30, and PTX + MSG60. Following the euthanizing, the body weight measurement, pituitary–testicular axis hormonal analysis and serum lipid peroxidation index assessment was prepared, testicular histomorphometry (tubular diameter and germinal epithelium height), immunohistochemistry of p53 was completed. Microscopic indices of spermatogenesis (tubular differentiation, spermiogenesis and repopulation indices) were studied.
Results: Body weight was not changed significantly. The levels of testosterone (p = 0.0001), follicle stimulating hormone (p = 0.019), and luteinizing hormone (p = 0.08) were decreased while the level of lipid peroxidation index was increased (p = 0.208) in the treated groups. The histomorphometry indices (p < 0.0001 and p = 0.001, respectively), germ cells population (p < 0.05) and microscopic indices of spermatogenesis (p = 0.001, p = 0.005, p < 0.0001, respectively) were significantly reduced in all treated groups. The administration of MSG before PTX treatment induces more changes. The most positive reaction to p53 was observed in MSG30 or 60 + PTX groups compared to other groups.
Conclusion: The administration of MSG could intensify testicular tissue alterations related to PTX chemotherapy.
Key words: Mice, Monosodium glutamate, Morphometry, Paclitaxel, Testicular tissue.

Ghasem Akbari

Papers

Morphological study of the European hedgehog (Erinaceus europaeus) tongue by SEM and LM

Development and evaluation of a technique for spinal anaesthesia in broiler chickens.

Comparison of Anesthetic Efficacy of Lidocaine and Bupivacaine in Spinal Anesthesia in Chickens

Effect of monosodium glutamate on testicular tissue of paclitaxel-treated mice: An experimental study.

Differential expression of small heat shock proteins in the brain of broiler embryo; the effects of embryonic thermal manipulation.