Genome-wide association study applied to type traits related to milk yield in water buffaloes (Bubalus bubalis).

This research aimed to estimate genetic parameters for milk yield and type traits [withers height (WH), croup height (CH), body length (BL), croup length (CL), iliac width (ILW), ischial width (ISW), and thoracic circumference] in Murrah buffaloes and to identify genomic regions related to type traits by applying a single-step genome-wide association study. Data used to estimate the genetic parameters consisted of 601 records of milk yield in the first lactation and the aforementioned type traits. For the single-step genome-wide association study, 322 samples genotyped with a 90K Axiom Buffalo Genotyping array (Thermo Fisher Scientific, Santa Clara, CA) were used. Bivariate analysis revealed that heritability for milk yield (kg) at 305 d was 0.31 ± 0.11, whereas it ranged from 0.22 ± 0.07 to 0.34 ± 0.09 for the studied conformation traits. Based on the percentages of genetic variance explained by windows of 10 markers, there were 16 genomic regions explaining more than 0.5% of the variance for WH, CH, BL, CL, ILW, ISW, and thoracic circumference. Between those regions, 4 were associated with more than 1 trait, suggesting pleiotropic roles for some genes of Bos taurus autosome (BTA) 12 on CL and WH, BTA13 on ISW and ILW, BTA23 on CH and BL, and BTA28 on ISW and BL. Most of these regions coincide with known quantitative trait loci for milk traits. Thus, further studies based on sequence data will help to validate the association of this region with type traits and likely identify the causal mutations.

Teat characteristics in relation to animal temperament during milking in buffaloes, and comparison of buffalo and cow teat morphology.

This study aimed to examine the teat characteristics in relation to the animal temperament during milking in the Anatolian buffaloes using ultrasonographic, histomorphological and immunohistochemical methods. The teat canal length (TCL), teat wall thickness (TWT), teat cisternal diameter (TCD), teat diameter (TD), teat length (TL), and teat circumference (TC) values in docile (n = 5) and nervous (n = 7) buffaloes were measured at the 0th, 3rd and 6th minute of stimulation. In additional experiments, comparative histomorphology and immunohistochemical examinations of buffalo (n = 7) and cow teats (n = 8) were performed. It was determined that post-stimulation mean TCL values were significantly higher in nervous buffaloes than those of teats in docile buffaloes (p < .05). A significant positive correlation between TCD and TD, TL and TC in both docile and nervous buffaloes was noted (p < .05). Unlike nervous buffaloes where only 3/14 teat canals were open by 3rd minute of milking stimulation, almost all (9/10) teat canals were observed opened in docile buffaloes. There were fewer muscle but more collagen bundles in buffalo teats compared with cow teats. It seems that temperament of animal during milking effects the milking efficiency, and in nervous buffaloes, probably the stimulation alone may not be sufficient for opening of the teat canal and hence achieve complete milking.

Relationship between angioarchitecture of the testicular artery and spermiogram parameters in Egyptian buffalo bulls (bubalus bubalis).

The current study aimed to investigate the effect of testicular artery angioarchitecture on the spermiogram parameters in Egyptian Buffalo bulls. Eight adult buffalo bulls aged between 2 and 8 years were used for semen evaluation. For anatomical studies, the masculine gonads were collected after slaughtering 30 adult bulls and prepared for injection by different masses (Urographine® , Latex and Epoxy) through the testicular artery. The mass activity of the ejaculate was assessed immediately after collection. The sperm motility in fresh bull ejaculate was more than 80%. The overall mean percentage of sperm abnormalities was <18%. The recorded sperm abnormalities were mostly secondary one including distal protoplasmic droplet, fragmented tail, detached head, detached galea capitis and bent tail. The highest percentage of sperm viability was recorded just after sperm collection (alive > 85%). The results revealed that testicular artery can be divided into three parts (abdominal, funicular and marginal parts) along its course. The coils of the funicular part forming a cone-like structure with its base fixed to the head of the testis. Two epididymal branches to the head and tail of epididymis emanate from the funicular part which continues as pars marginalis on the lateral surface of testis before its division into the lateral and medial testicular arteries on approaching the tail extremity of the testis. The increase in the length of the testicular artery with increase in the size of the testes played a great role in the degree of complexity of the architectural vascular patterns. The degree of complexity is affected by the number of coils formed by the vessel. The increase in the convolutions of the vessel will reduce the speed of blood flow to the gonads. Thus in turn will enabling the thermoregulatory mechanism to work more efficiently and will affect the semen value.

Genome-wide association study for buffalo mammary gland morphology.

This research communication describes a genome-wide association study for Italian buffalo mammary gland morphology. Three single nucleotide polymorphisms (AX-85117983, AX-8509475 and AX-85117518) were identified to be significantly associated with buffalo anterior teat length, posterior teat length and distance between anterior and posterior teat, respectively. Two significant signals for buffalo mammary gland morphology were observed in two genomic regions on the chromosome 10, and chromosome 20. One of the regions located on the chromosome 10 has the most likely candidate genes ACTC1 and GJD2, both of which have putative roles in the regulation of mammary gland development. This study provides new insights into the genetic variants of buffalo mammary gland morphology and may be beneficial for understanding of the genetic regulation of mammary growth.

Utilization of live body weight, measurements, and eye muscle components to predict carcass performance of fattened Egyptian male buffalo calves.

Carcass performance of 12 fattened male buffalo calves equally grouped by slaughter weights of 300, 350, 400, and 450 kg was evaluated. Six parameters of body measurements such as chest girth, height at withers, body length, body depth, width at pin bones, and diagonal body length were recorded for each calf immediately before slaughter to test their relationships with live body weight, carcass weight (hot and cold) and its components (head, legs, liver, heart, etc.), and eye muscle area at the 10th-13th ribs. Boneless meat and bones formed 36.6 to 39.0% and 9.3 to 11.0% of live weight, respectively. Chest girth had strong correlation with all carcass traits except bone weight and was the best predictor of boneless meat and carcass fat weights (R2 = 0.90, 0.78). The slaughter weight and height at withers and the 10th-13th rib fat weight were the best predictors of hot and cold carcass (R2 ≥ 97.0), carcass bones (R2 = 76%), and hot and cold carcass (R2 = 85.0, 86.5%) weights, respectively.

Comparative View of Lung Vascular Endothelium of Cattle, Horses, and Water Buffalo.

Endothelium plays an important role in maintaining the vascular barrier and physiological homeostasis. Endothelium also is fundamental to the initiation and regulation of inflammation. Endothelium demonstrates phenotypic and functional heterogeneity not only among various organs but also within an organ. One of the striking examples would be the pulmonary endothelium that participates in creating blood-air barrier. Endothelium in large pulmonary blood vessels is distinct in structure and function from that lining of the pulmonary capillaries. This chapter focuses on the comparative aspects of pulmonary endothelium and highlight unique differences such as the presence of pulmonary intravascular macrophages among select species.

Body size and the division of niche space: food and predation differentially shape the distribution of Serengeti grazers.

1. Theory predicts that small grazers are regulated by the digestive quality of grass, while large grazers extract sufficient nutrients from low-quality forage and are regulated by its abundance instead. In addition, predation potentially affects populations of small grazers more than large grazers, because predators have difficulty capturing and handling large prey. 2. We analyse the spatial distribution of five grazer species of different body size in relation to gradients of food availability and predation risk. Specifically, we investigate how the quality of grass, the abundance of grass biomass and the associated risks of predation affect the habitat use of small, intermediate and large savanna grazers at a landscape level. 3. Resource selection functions of five mammalian grazer species surveyed over a 21-year period in Serengeti are calculated using logistic regressions. Variables included in the analyses are grass nitrogen, rainfall, topographic wetness index, woody cover, drainage lines, landscape curvature, water and human habitation. Structural equation modelling (SEM) is used to aggregate predictor variables into 'composites' representing food quality, food abundance and predation risk. Subsequently, SEM is used to investigate species' habitat use, defined as their recurrence in 5 × 5 km cells across repeated censuses. 4. The distribution of small grazers is constrained by predation and food quality, whereas the distribution of large grazers is relatively unconstrained. The distribution of the largest grazer (African buffalo) is primarily associated with forage abundance but not predation risk, while the distributions of the smallest grazers (Thomson's gazelle and Grant's gazelle) are associated with high grass quality and negatively with the risk of predation. The distributions of intermediate sized grazers (Coke's hartebeest and topi) suggest they optimize access to grass biomass of sufficient quality in relatively predator-safe areas. 5. The results illustrate how top-down (vegetation-mediated predation risk) and bottom-up factors (biomass and nutrient content of vegetation) predictably contribute to the division of niche space for herbivores that vary in body size. Furthermore, diverse grazing assemblages are composed of herbivores of many body sizes (rather than similar body sizes), because these herbivores best exploit the resources of different habitat types.

Follicular characteristics and intrafollicular concentrations of nitric oxide and ascorbic acid during ovarian acyclicity in water buffalo (Bubalus bubalis).

The objective of this study was to examine the follicular characteristics and intrafollicular concentrations of nitric oxide and ascorbic acid during ovarian acyclicity in buffaloes. Ovaries were collected from 56 acyclic and 95 cyclic buffaloes at slaughter, surface follicle number was counted and follicles were classified into small (5.0-6.9 mm), medium (7.0-9.9 mm), and large (≥ 10.0 mm) size categories based on their diameter. Follicular fluid was aspirated and assayed for nitric oxide, ascorbic acid, estradiol, and progesterone. Acyclic buffaloes had a higher (P<0.05) number of medium-sized follicles and a lower (P<0.001) number of large follicles than the cyclic ones. In acyclic animals, the number of large follicles was lower (P<0.01) than in medium size category which in turn was lower (P<0.001) than the number of small follicles. In contrast, the number of medium and large follicles was not different (P>0.05) in the cyclic control. However, the number of small-sized follicles was higher (P<0.001) compared to the other two categories. The incidence of large-sized follicles was lower (P<0.05) in acyclic buffalo population compared to the cyclic control. Evaluation of estrogenic status demonstrated that all the follicles of acyclic buffaloes are estrogen-inactive (E (2)/P (4) ratio<1). Small- and medium-sized follicles of acyclic buffaloes had higher concentrations of nitric oxide (P<0.05 and P<0.001, respectively) and lower concentrations of ascorbic acid (P<0.05 and P<0.01, respectively) than the corresponding size estrogen-active follicles of their cyclic counterparts. In conclusion, this study indicates that follicular development continues during acyclicity in buffaloes. Although follicles in some acyclic buffaloes attain a size corresponding to morphological dominance, they are unable to achieve functional dominance, perhaps due to an altered balance of intrafollicular nitric oxide and ascorbic acid and, as a result, these follicles instead of progressing to ovulation undergo atresia.

Ultrastructural features on the oral cavity floor (tongue, sublingual caruncle) of the Egyptian water buffalo (Bubalus bubalis): gross, histology and scanning electron microscope.

BACKGROUND: The present work was focused on the evaluation of morphological characteristics of the lingual caruncles and tongue with its papillae of Egyptian water buffalo (Bubalus bubalis) using gross examination, light and scanning electron microscopy. MATERIALS AND METHODS: The ventral surface of the sublingual caruncle carried a small opening of the duct of both monostomatic and mandibular salivary gland. The lingual mucosa of dorsal, lateral border and, to some extent, of ventral surface of apex had lingual papillae (filiform, fungiform), while the lingual mucosa of the lingual body especially at torus linguae had conical papillae, but circumvallate papillae observed at the caudal part of body and root. The dorsal surface of the apex and body carried numerous long, thread-like, with blunt apex, caudally directed filiform papillae that covered with keratinised scales without secondary papillae. RESULTS: The degree of keratinisation classified filiform papillae into rostral part of high keratinisation and caudal of less keratinisation. Conical papillary surface carried exfoliated epithelium with longitudinal groove on its rostral surface and carried secondary papillae. Fungiform papillae were scattered among filiform papillae on the dorsal and ventral surface of the apex and its convex surface had exfoliated keratinised epithelium. Circumvallate papillae were surrounded by circular deep groove bordered by vallum that carried small secondary papillae that ended into the primary groove. Taste buds of circumvallate papillae opened in the lateral lining epithelium facing the groove. CONCLUSIONS: Von Ebner's glands were observed in computed tomography under papillae especially toward the groove and their ducts open into the base of the groove.

Detailed gross anatomic and sialographic characteristics of major salivary glands in water buffaloes (Bubalus bubalis).

To clarify the detailed general architecture and topography of major salivary glands and demonstrate a fine anatomy of the ductal system of the glands in water buffaloes, we conducted gross anatomic and sialographic investigations of glands in 14 half heads from seven water buffaloes. The position of the mandibular gland, course of mandibular duct relative to monostomatic gland, a rostral extension of polystomatic gland, and site of origin of monostomatic duct in buffaloes essentially differed from those of various ruminants. The shape of the parotid and mandibular glands, and origin of their ducts, lacking filling of retromandibular fossa by parotid gland, the topography of mandibular gland relative to the parotid gland and mandibular lymph node, caudal extension of polystomatic gland, rostral extension of monostomatic gland, and location of polystomatic gland relative to monostomatic gland in buffaloes were very similar to those in ox. However, several considerable differences in morphology of glands in buffaloes and ox were recognized. Major salivary glands in buffaloes almost show 'grazing ruminants' morphological and morphometrical characteristics. Within parotid, mandibular, and monostomatic glands in buffaloes, there was a ductal arborization pattern in lateral sialograms. Whereas the main parotid duct was formed by a union of two central branches of the intraglandular duct, main mandibular, and monostomatic ducts were consisted of one central branch. The pattern of peripheral branches from the central branch of intraglandular duct in buffaloes was significantly different among the glands. Our detailed sialography of ductal morphology and morphometry can be helpful in accurate diagnosis of gland diseases in live water buffaloes.

Ultrasonographic assessment of change in omasal position during the last month of gestation and first month of lactation in buffaloes.

INTRODUCTION: This study was aimed to determine the effect of advanced pregnancy on the topography and size of the omasum in 22 healthy Murrah buffaloes. The omasum was scanned 15-20 days before and after parturition, as per the standard procedure. The dorsal and ventral margins of the omasum were identified and marked at each intercostal space (ICS). The dorsal and ventral limits up to the dorsal midline were measured. The omasum was scanned in 6th to 11th ICS during advanced pregnancy and 7th to 11th ICS after the parturition. Irrespective of the pregnancy, the dorsal and ventral margins of the omasum were located farther dorsal and close to the spine in the 6th, 7th and 11th ICS. Except in one buffalo, the omasum was scanned in four consecutive ICS during the advanced pregnancy. After parturition the omasum was scanned in four and five consecutive ICS in 17 and five buffaloes, respectively. The mean dorsal and ventral limits of the omasum increased significantly (P .

INTRODUCTION: Cette étude visait à déterminer l'effet d'une gestation avancée sur la topographie et la taille de l'omasum chez 22 buffles de Murrah en bonne santé. L'omasum a été scanné 15 à 20 jours avant et après la parturition, selon la procédure standard. Les marges dorsale et ventrale de l'omasum ont été identifiées et marquées au niveau de chaque espace intercostal (EIC). Les limites dorsale et ventrale jusqu'à la ligne médiane dorsale ont été mesurées. L'omasum a été scanné du 6ème au 11ème EIC pendant la gestation avancée et du 7ème au 11ème EIC après la mise-bas. Indépendamment de la gestation, les marges dorsale et ventrale de l'omasum étaient situées plus loin dorsalement et plus près de la colonne vertébrale dans les 6ème, 7ème et 11ème EIC. Sauf chez un buffle, l'omasum a été scanné dans quatre EIC consécutifs au cours de la gestation avancée. Après la mise-bas, l'omasum a été scanné dans quatre et cinq EIC consécutifs chez 17 respectivement 5 buffles. Les limites dorsales et ventrales moyennes de l'omasum ont augmenté de manière significative (P.

Histology of hemal nodes of the water buffalo (Bos bubalus).

Hemal nodes are independent lymphoid organs found in various mammals but are ignored by most immunologists. They seem to play a role in defense against blood-borne infections in some species. The structure of the hemal node has been described in various species but, so far, not in the water buffalo. Specimens were obtained from ten clinically healthy male animals (five calves: 2-3 months old; five bulls: 2-8 years old). Six hemal nodes were obtained from each animal from the mesenteric and perirectal region. The samples were studied by light and transmission electron microscopy. The hemal nodes are bean-shaped or spherical, with one hilus through which the hilus arteries and nerves enter the node and from which veins and lymphatics leave it. The buffalo hemal node has a thin capsule of connective tissue and a few smooth muscle cells. Trabeculae extend from the capsule partially dividing the parenchyma. Subcapsular and trabecular blood sinuses are present. The parenchyma is composed of irregular lymphoid cords rich in erythrocytes, macrophages, and plasma cells and is separated by blood sinuses of variable size engorged with blood. These blood sinuses drain into the trabecular sinuses and then into the subcapsular sinus. In calves, the size of the lymphoid cords is larger than that in adult bulls. Buffalo hemal nodes can be classified as typical hemal nodes, because they are definitely different from hemolymph nodes in other species. They may play a role in filtering the blood.

Ultrastructure of in vitro oocyte maturation in buffalo (Bubalus bubalis).

The objective of the present study was to describe ultrastructural changes in the nucleus and cytoplasmic organelles during in vitro maturation (IVM) of buffalo cumulus-oocyte complexes (COCs). The structures were collected by ovum pick-up (OPU). Some COCs, removed from maturation medium at 0, 6, 12, 18 and 24 h, were processed for transmission electron microscopy. The average number of COCs collected by OPU/animal/session was 6.4, and 44% of them were viable. Immature oocytes had a peripherally located nucleus, Golgi complex and mitochondrial clusters, as well as a large number of coalescent lipid vacuoles. After 6 h of IVM, the oocyte nucleus morphology changed from round to a flatter shape, and the granulosa cells (GC) lost most of their contact with zona pellucida (ZP). At 12 h the first polar body was extruded and the aspect of lipid droplet changed to dark, probably denoting lipid oxidation. Cortical granules were clearly visible at 18 h of maturation, always located along the oocyte periphery. At 24 h of IVM the number of cortical granules increased. Ultrastructure studies revealed that: (1) immature oocytes have a high lipid content; (2) the perivitelline space (PS) increases during IVM; (3) Golgi complexes and mitochondrial clusters migrate to oocyte periphery during IVM; (4) 6 h of IVM are enough to lose contact between GC and ZP; (5) the oocyte lipid droplets' appearance changes between 6 and 12 h of IVM.

Teat anatomy affects requirements for udder preparation in Mediterranean buffaloes.

The present study was conducted to assess the interrelation between teat anatomy and machine milking in dairy buffaloes raised in Switzerland. A 3-min pre-stimulation induced milk ejection before cluster attachment in most cases and caused an optimal milk removal during machine milking. In an additional experiment, longitudinal cross-section ultrasound was obtained before and after a 3-min pre-stimulation. Teat wall thickness, teat diameter, cisternal diameter and teat canal length were evaluated. It was observed that 3-min pre-stimulation dramatically reduced teat canal length whereas all the other anatomical parameters remained unchanged. The vacuum needed to open the teat canal was also measured before and after a 3-min pre-stimulation by using a special teat cup with only the mouthpiece of the liner remaining on the top of the teat cup (no liner, no pulsation). Without pre-stimulation but after wetting the teat canal by stripping one squirt of milk out of the teat, no milk could be withdrawn with a vacuum up to 39 kPa. However, after pre-stimulation, milk flow occurred in all buffaloes at a vacuum between 16 and 38 kPa. In the last experiment, the teat tissue was examined in slaughtered buffaloes and compared with teat tissue of cows. No difference was noted in histological sections and teat canal length was similar in cows and buffaloes. Proximal to the teat canal, the teat did not pass into an open cistern but the lumen was collapsed. In conclusion, buffaloes need to be well pre-stimulated because the tissue above the teat canal provides additional teat closure before milk ejection. Therefore, milk can only be obtained after pre-stimulation.

Genetic and morphometric characterization of a local Vietnamese swamp buffalo population.

The water buffalo plays a key role in the socio-economy of South-East Asia as it is the main draught power for paddy rice cultivation. While in the Indian subcontinent the water buffalo is the riverine type, in South-East Asia the majority of buffaloes are of the swamp type. In the poor remote northern province of Ha Giang in Vietnam, improvement of the swamp buffalo breed may be one of the best ways to increase sustainability of farming systems. Therefore, analysis of the genetic structure of the province buffalo population is a prerequisite to any conservation or improvement project. A total of 1122 animals were described for 11 body and horn measurements for morphometric characterization. From this sample set, 744 animals were genotyped for 17 microsatellite markers. Also 17 animals from southern provinces of Vietnam were genotyped as a comparative sample. The results showed that genetic diversity as well as inbreeding value in the Ha Giang was high. The F(ST) values within the province and across Vietnam were low indicating that most of the population variation is explained by individual variability. Bayesian clustering analysis did not highlight the presence of subdivided populations. These results are useful for the implementation of a conservation and improvement strategy of the swamp buffalo in order to guarantee the householders' needs for sustainability of the farming system in the Ha Giang province.

Normal anatomic reference of pastern and coffin joints in Egyptian buffalo (Bubalus bubalis): A compared atlas of cross-sectional anatomy, magnetic resonance imaging and computed tomography.

The purpose of this study was to describe normal magnetic resonance imaging and computed tomographic anatomy of pastern and coffin joints in Egyptian buffalo using cadaveric distal limbs. This study was achieved using twelve fresh cadaveric distal limbs from adult healthy buffaloes of both sexes. These cadaveric limbs were scanned using a 1 Tesla MRI scanner and CT scanner, injected with red latex, frozen at -20°C for 1 week, and then sectioned into sagittal, dorsal and transverse slices. The obtained MR and CT images were selected to be matched with their corresponding anatomical cross-sections for identification and evaluation of the clinically correlated anatomical structures of the pastern and coffin joints. The difference in signal intensities on CT and MRI scans amongst the tissues allowed clear differentiation of major bone and soft tissue structures of the pastern and coffin joints. CT provided a high spatial resolution of bone and soft tissue structures, however, MRI allowed a better and higher resolution and definition between soft tissues. The current study provided a normal CT and MRI anatomic reference which could help veterinary clinicians for interpretation and diagnosis of the clinically affected pastern and coffin joints in buffalo.

Histomorphometric analysis of the irides of dogs, camels, buffalos and donkeys.

The present study was carried out to investigate the morphological and histomorphometrical characters of irides in dogs, camels, buffalos, and donkeys. The findings of the study revealed that, morphologically, the irides were consisted of an anterior border layer, a middle layer of connective tissue stroma and a posterior layer of pigmented epithelium. Interestingly, the anterior borders of all investigated animals were not enveloped by a distinct epithelial or endothelial lining, but on contrary, the posterior border was covered by pigmented epithelium. The constrictor and dilator iridial muscles were well developed in dogs, weakly developed in donkeys, and with an intermediate position in camels and buffalos. Morphometric analysis revealed significant species differences in the mean total thickness of the iris and its different layers. In addition significant differences were also found between the ratio of the means of different layers to the total thickness of the iris at the pupillary, middle and ciliary borders. In conclusion, these variations might be related to the different lifestyles and visual behaviour of the investigated animals.

Light and scanning electron microscopic studies of oviductal epithelium in Thai swamp buffalo (Bubalus bubalis) at the follicular and luteal phases.

The purpose of this study was to investigate the morphological changes in the epithelium of Thai swamp buffalo oviducts at the follicular and luteal phases by histological technique and scanning electron microscopy. The samples from the infundibulum, ampulla, isthmus and uterotubal junction (UTJ) of the oviduct were taken immediately after slaughter at the local abattoir. Noticeable cyclic changes were observed on the epithelial surface of the infundibulum and ampulla, but few changes were present in the isthmus and UTJ. At the follicular phase, the epithelium of infundibulum and ampulla were densely covered with ciliated cells whose cilia concealed the apical processes of the secretory cells. In contrast, the secretory cells dominated in the epithelium at the luteal phase and most of the ciliated cells were hidden by the bulbous processes of these cells. In the isthmus and UTJ at the follicular and luteal phases, the secretory cells were almost flat or gently rounded and covered with numerous microvilli at their apical surface. In conclusion, the histological and ultrastructural observation of Thai swamp oviduct epithelium revealed marked cyclic changes in the cellular differences associated with the main functions of segmental variations.

Bilateral primary spontaneous pneumothorax: buffalo chest.

A case of bilateral primary spontaneous pneumothorax ("buffalo chest") in a previously healthy man is described. The clinical presentation and treatment options are discussed.

Histology, histochemistry and ultrastructure of the nasopharyngeal tonsil of the buffalo (Bubalus bubalis).

The light microscopic appearance and ultrastructure of the nasopharyngeal tonsil (tonsilla pharyngea), collected from 12 adult buffaloes of local mixed breed, were explored for the distribution of different types of epithelia, lymphoid tissue and high endothelial venules. The tonsillar mucosa was lined by pseudostratified columnar ciliated epithelium having goblet cells. The respiratory epithelium associated with the underlying lymphoid tissue formed the lymphoepithelium. The epithelium was further modified into follicle-associated epithelium (FAE) characterized by reduced epithelial height, presence of a few dome-shaped cuboidal cells equivalent of the M-cells and absence of goblet and ciliated cells. The lymphoid tissue was distributed in the form of isolated lymphoid cells, diffuse lymphoid tissue and lymphoid follicles, mainly distributed within the propria-submucosa along with the sero-mucous glandular tissue. The goblet cells of the respiratory epithelium and the acinar cells contained different mucopolysaccharides. Scanning electron microscopy of the surface mucosa demonstrated a dense mat of cilia, island-like arrangement of microvillus cells, M-cells and a few brush-like cells. The transmission electron microscopy revealed the different cell organelles of the respiratory epithelium and the FAE. Lymphocyte migration via the high endothelial venules in the propria-submucosa was also observed.