The goal of the present study was to screen for urinary bladder affections in camels and correlate it with physicochemical, microscopical, bacterial and pathological changes. A total number of 25 male camels (3-12 years old) were subjected to study. Animals were slaughtered in Bani Adi slaughter house (Assiut, Egypt) during the period from February to May 2009. The urinary bladder was collected under complete aseptic conditions from each slaughtered animal just after evisceration. Urine samples were drawn using sterile syringe and used for both conventional urine analysis and bacteriological examination. An incision was made in the bladder and then it was examined macroscopically for presence of any pathological affection. A part from the bladder wall was kept in neutral buffered formalin for histopathological examination. According to the histopathological findings, camels under investigation were classified into three groups; acute cystitis group (n: 10), chronic cystitis group (n: 8) and control group (n: 7). Seventy two percentages of camels were found suffering from cystitis; out of them, 48% aged 3-7 years old and 24% were above 7 years old. The relationships between pathological changes of the bladder and urine analysis were discussed. The bacteriological examination revealed isolation of Staphylococcus sp. (54.54%), Corynebacterium sp. (27.27%) and E. coli sp. (18.18%) from the camel's urine. In conclusion, incidence of cystitis is higher in young camels than older ones. Urine analysis is helpful in diagnosis of chronic cystitis. Since the incidence of cystitis was rather high in studied period, further studies are required to elucidate the relationship between the season and cystitis in camel.

Seven hundred and eighty seven random milk samples were collected from cows and buffaloes at different localities and farms in Assiut Governorate. These samples represented by 379 and 408 quarter milk samples from 105 cows and 105 buffaloes, respectively. Animal-wise incidence of Subclinical Mastitis (SCM) based on California Mastitis Test (CMT) and Modified Whiteside Test (MWST) were 59.05 & 60.95% positive in cows and 33.33% & 33.33% positive in buffaloes, respectively. The animal-wise incidences of SCM in cows & buffaloes by bacteriological and mycological examinations were 60.95 & 28.57% and 34.29 & 0.95% positive, respectively. The most common bacteria causing SCM in cows were Staph. aureus, coagulase negative staphylococci (CNS), Str. pyogenes, Str. agalactiae, Str. dysgalactiae, E. coli, Klebsiella pneumoniae, Citrobacter diversus and Proteus mirabilis, respectively. While, in buffaloes were Staph. aureus, CNS, Str. pyogenes, Str. dysgalactiae and Corynebacterium bovis. Additionally, the most common yeasts and molds causing SCM in cows were Candida albicans, Candida tropicalis, Candida krusei, Candida sp., Geotrichum candidum, Aspergillus niger, Cladosporium cladosporioides, Fusarium proliferatum, Penicillium duclauxi, Rhodotorula sp., Stachybotrys elegans, near to Pyssochlamys nivea, Alternaria alternata, Stemphylium botryosum, Thermoascus aurantiacus, Trichosporon cuteanum and sterile mycelium. However, Phialophora sp. was only isolated from buffaloes in a percentage of 0.25%.

Seven hundred and eighty seven random milk samples were collected from cows and buffaloes at different localities and farms in Assiut Governorate. These samples represented by 379 and 408 quarter milk samples from 105 cows and 105 buffaloes, respectively. Animal-wise incidence of Subclinical Mastitis (SCM) based on California Mastitis Test (CMT) and Modified Whiteside Test (MWST) were 59.05 & 60.95% positive in cows and 33.33% & 33.33% positive in buffaloes, respectively. The animal-wise incidences of SCM in cows & buffaloes by bacteriological and mycological examinations were 60.95 & 28.57% and 34.29 & 0.95% positive, respectively. The most common bacteria causing SCM in cows were Staph. aureus, coagulase negative staphylococci (CNS), Str. pyogenes, Str. agalactiae, Str. dysgalactiae, E. coli, Klebsiella pneumoniae, Citrobacter diversus and Proteus mirabilis, respectively. While, in buffaloes were Staph. aureus, CNS, Str. pyogenes, Str. dysgalactiae and Corynebacterium bovis. Additionally, the most common yeasts and molds causing SCM in cows were Candida albicans, Candida tropicalis, Candida krusei, Candida sp., Geotrichum candidum, Aspergillus niger, Cladosporium cladosporioides, Fusarium proliferatum, Penicillium duclauxi, Rhodotorula sp., Stachybotrys elegans, near to Pyssochlamys nivea, Alternaria alternata, Stemphylium botryosum, Thermoascus aurantiacus, Trichosporon cuteanum and sterile mycelium. However, Phialophora sp. was only isolated from buffaloes in a percentage of 0.25%.

Fifteen male Rahmani lambs (8 months in age with an average body weight 30.52 ± 0.21 Kg) were used in this study to evaluate the effect of different protein levels in diets on the performance, nutrient digestibility, blood parameters, ruminal characteristics and carcass traits in addition to economical benefit. Animals were randomly divided into 3 similar groups (5 lambs each). Each group was fed on one of the protein level tested (12, 14.70 & 17% CP) for 90 days. The medium protein's ration (14.7 %) was considered as control. The two different protein levels as treatments (high protein, HP = 17%, low protein, LP= 12%). All diets contained the same digestible energy (3.20 MCal/kg DE / kg diet). There was significant (P0.05) difference in the feed intake, weight gain and feed conversion between different experimental groups. The apparent digestion coefficients of DM, CP, EE, CF & NFE were significantly (P0.05) increased with increasing dietary protein levels. There was significant (P0.05) increase in the total protein, albumin, globulin and urea as the protein level increased. The levels of protein had no significant effect on the pH of the rumen, while ammonia-N concentration and total volatile fatty acids were significantly (P0.05) increased. There were no significant differences in the carcass characteristics between treated groups. Consequently, it was considered that feeding Rahmani lambs with higher protein level than 14.7% had no advantage for performance and would be cause of economic loss, it can be said that, 14.7% CP was optimal.

The mammalian thyroid gland contains a secondary structure, the ultimobranchial body remnants (UBBRs), which is incorporated into thyroid parenchyma and remains there as scattered parafollicular and interfollicular calcitonin secreting cells or gathered into follicle-like structures and cellular clusters, termed solid cell nests (SCNs) and cystic cell nests (CCNs). The UBBRs of present study have been revealed as ectopic structures of various forms and sizes alongside with the usual thyroid follicles which demonstrated in form of large follicles or cysts, large ducts or branching tubules, irregular or labyrinth-like follicles locating under the capsule or deeply situated in the interstitial connective tissue of donkey's thyroid gland. In addition, several small secondary or differentiating follicles, epithelial outgrowths, as well as various cellular aggregates that described in form of SCNs or CCNs were also demonstrated in close vicinity with the aforementioned structures. Mixed ultimobranchial follicles (UBFs) might be found to be admixed with SCNs which composed of solid cell nests cells and follicular cells, forming lumen-like pattern were also demonstrated. The lining epithelium of UBFs was mostly cuboidal in appearance, but sometimes varied from squamous to pseudostratified or stratified in form. The cellular components of UBFs were consisted of usual follicular cells and clear or calcitonin cells. Meanwhile, the SCNs were comprised of main polygonal cells with eosinophilic cytoplasm and large sized calcitonin cells (C-cells) with pale staining cytoplasm which accounts a minor cellular proportion. Surface of most ultimobranchial (UB) follicular cells was almost hexagonal in shape, studded with sparse or dense pleomorphic microvilli, which were denser at the cellular borders. Each follicular cell bore single cilium that projecting over the cell surface. Interestingly, bleb-like apocrine protrusion of the apical cytoplasm of some UB follicular cells was frequently demonstrated. These apocrine blebs (aposomes) were varied in shape, size and showed smooth or irregular surface. In addition to such aposomes, deep to shallow circumscribed or eroded areas of the apical cell surface was frequently demonstrated. These features indicate that the UB follicular cells in donkeys are similar to those of buffaloes and exhibit an apocrine activity alongside with the usual merocrine mode of secretion. In conclusion, although minor in mass, UBB contribution to the thyroid is important because this structure has been cited as the source of C-cells in mammals including human. Despite the biologic significance of UBBRs remains disputable, the heterogenous expression of antigens in SCNs has indicated that the cells comprising these structures have different biologic functions; at least some C-cells and follicular cells would originate in SCNs. Furthermore, it has been suggested that these remnants might constitute the origin of some ectopic structures described in the thyroid gland including some types of thyroid neoplasms. Abbreviations used in this study: APUD cells, amine precursor uptake and decarboxylation cells; C-cells, Calcitonin cells; CCN(s), cystic cell nest(s); SCN(s), Solid cell nest(s); UB, ultimobranchial; UBB, ultimobranchial body; UBF(s), ultimobranchial follicle(s); UBBR(s), ultimobranchial body remnant(s).

The mammalian thyroid gland contains a secondary structure, the ultimobranchial body remnants (UBBRs), which is incorporated into thyroid parenchyma and remains there as scattered parafollicular and interfollicular calcitonin secreting cells or gathered into follicle-like structures and cellular clusters, termed solid cell nests (SCNs) and cystic cell nests (CCNs). The UBBRs of present study have been revealed as ectopic structures of various forms and sizes alongside with the usual thyroid follicles which demonstrated in form of large follicles or cysts, large ducts or branching tubules, irregular or labyrinth-like follicles locating under the capsule or deeply situated in the interstitial connective tissue of donkey's thyroid gland. In addition, several small secondary or differentiating follicles, epithelial outgrowths, as well as various cellular aggregates that described in form of SCNs or CCNs were also demonstrated in close vicinity with the aforementioned structures. Mixed ultimobranchial follicles (UBFs) might be found to be admixed with SCNs which composed of solid cell nests cells and follicular cells, forming lumen-like pattern were also demonstrated. The lining epithelium of UBFs was mostly cuboidal in appearance, but sometimes varied from squamous to pseudostratified or stratified in form. The cellular components of UBFs were consisted of usual follicular cells and clear or calcitonin cells. Meanwhile, the SCNs were comprised of main polygonal cells with eosinophilic cytoplasm and large sized calcitonin cells (C-cells) with pale staining cytoplasm which accounts a minor cellular proportion. Surface of most ultimobranchial (UB) follicular cells was almost hexagonal in shape, studded with sparse or dense pleomorphic microvilli, which were denser at the cellular borders. Each follicular cell bore single cilium that projecting over the cell surface. Interestingly, bleb-like apocrine protrusion of the apical cytoplasm of some UB follicular cells was frequently demonstrated. These apocrine blebs (aposomes) were varied in shape, size and showed smooth or irregular surface. In addition to such aposomes, deep to shallow circumscribed or eroded areas of the apical cell surface was frequently demonstrated. These features indicate that the UB follicular cells in donkeys are similar to those of buffaloes and exhibit an apocrine activity alongside with the usual merocrine mode of secretion. In conclusion, although minor in mass, UBB contribution to the thyroid is important because this structure has been cited as the source of C-cells in mammals including human. Despite the biologic significance of UBBRs remains disputable, the heterogenous expression of antigens in SCNs has indicated that the cells comprising these structures have different biologic functions; at least some C-cells and follicular cells would originate in SCNs. Furthermore, it has been suggested that these remnants might constitute the origin of some ectopic structures described in the thyroid gland including some types of thyroid neoplasms. Abbreviations used in this study: APUD cells, amine precursor uptake and decarboxylation cells; C-cells, Calcitonin cells; CCN(s), cystic cell nest(s); SCN(s), Solid cell nest(s); UB, ultimobranchial; UBB, ultimobranchial body; UBF(s), ultimobranchial follicle(s); UBBR(s), ultimobranchial body remnant(s).

The remnants of ultimobranchial body (UBB) in the thyroid gland of adult buffalo were studied. This remnant occupied a peripheral location beneath the capsule, as well as being embedded mostly in the vascular connective tissue of the thyroid. It demonstrated as microscopic nodules (ultimobranchial nodules, UB nodules), in the vicinity of thyroid capsule, septa or frequently embedded within the thyroid tissue proper. The UB nodules were consisted of various aggregations of striking follicles (ultimobranchial follicles, UBFs), exhibiting unusual shape and size and sometimes exhibited unusual lining epithelium. The UBFs had cystic-, elongated-, tubular-, duct- or labyrinth-like formations of various sizes with irregular outline and more or less folded lumen. This lumen might contain debris of disintegrating cells and/or colloid. Apart from the aggregated UB structures, occasional solitary UBFs or other related derivatives were rarely distributed within the thyroid tissue proper. The UBFs were lined with a single layer of cubical, columnar, flattened or sometimes pseudostratified epithelial formations. Solid cell nests (SCNs), as well as some cystic follicles exhibiting both simple and stratified epithelial variety were also demonstrated. In addition, mixed UB follicles that lined with both simple and stratified epithelium were also revealed. Thyrocalcitonin cells (C-cells), with various cytoplasmic intensities of immunoreactive products against anti-calcitonin human immune serum, were predominantly localized in the wall of UBFs. These cells distributed singly or in groups between the component cellular elements lining of UB structures. They characterized by the presence of fine electron dense membrane-bound granules (150-200 nm) scattered in the cytoplasm together with several mitochondria, small profiles of rough endoplasmic reticulum, as well as few small-flattened cisternae of Golgi apparatus. Scanning electron microscopy revealed that the surface of UB follicular cells was almost flat and polyhedral or hexagonal in shape. Other follicles possessed some cells with dome shaped apical surface demarcated by a shallow intercellular depression. The luminal surface of follicular cell lining was studded with pleomorphic microvilli which were numerous at the intercellular borders. Interestingly, most of UB follicular cells were provided with single cilium, projecting over the cell surface. Notably, some UBFs presented various stages of apocrine activities. Abbreviations used in this study: APUD cells, amine precursor uptake and decarboxylation cells; C-cells, Calcitonin cells; CCN(s), cystic cell nest(s); SCN(s), Solid cell nest(s); UB, ultimobranchial; UBB, ultimobranchial body; UBF(s), ultimobranchial follicle(s); UBBR(s), ultimobranchial body remnant(s).

The present work was conducted to highlight the relationship between the external morphology of O. niloticus and the histomorphological changes of the testes during the breeding and the non breeding seasons. A total of 58 male fishes of O. niloticus were used in this investigation. The males showed bright black coloration on the dorsal and lateral parts of their body and red colour on the ventral part of their body and head during the breeding season. Testes were paired long narrow structure of approximate equal size, locating in the posterior body cavity, attached to the dorsal body wall by mesorchium. During the non-breeding season, the testes were small, thread- like and dull white in colour. During the breeding season, testes were pinkish in colour and increased in weight. The testis was covered with a capsule consisting of few collagenous, elastic fibers. Testicular parenchyma consisted of branched seminiferous tubules and interstitial tissue. The seminiferous tubules were lined with spermatogenic and Sertoli cells. Seminiferous tubules were made up of spermatocysts. During spermatogenesis, primary spermatogonia proliferated to form secondary spermatogonia which divided mitotically to form primary spermatocytes. The later underwent meiotic divisions to form secondary spermatocytes that passed with second meiotic divisions giving many spermatids which transformed into spermatozoa in the lumen of the seminiferous tubules. Sertoli cells were pyriform cells with slightly eosinophilic cytoplasm and one basal nucleus. During the non- breeding seasons, the diameter of the seminiferous tubules reached 102.94 + 1..83 µm and the mean number of Sertoli cells was 1.79 + 0.16 /spermatocyst. During the breeding season, the diameter of the seminiferous tubules was 124.78 + 2.32 µm and the mean number of Sertoli cells was 3.01 + 0.14/ spermatocyst.

The present work was conducted to highlight the relationship between the external morphology of O. niloticus and the histomorphological changes of the testes during the breeding and the non breeding seasons. A total of 58 male fishes of O. niloticus were used in this investigation. The males showed bright black coloration on the dorsal and lateral parts of their body and red colour on the ventral part of their body and head during the breeding season. Testes were paired long narrow structure of approximate equal size, locating in the posterior body cavity, attached to the dorsal body wall by mesorchium. During the non-breeding season, the testes were small, thread- like and dull white in colour. During the breeding season, testes were pinkish in colour and increased in weight. The testis was covered with a capsule consisting of few collagenous, elastic fibers. Testicular parenchyma consisted of branched seminiferous tubules and interstitial tissue. The seminiferous tubules were lined with spermatogenic and Sertoli cells. Seminiferous tubules were made up of spermatocysts. During spermatogenesis, primary spermatogonia proliferated to form secondary spermatogonia which divided mitotically to form primary spermatocytes. The later underwent meiotic divisions to form secondary spermatocytes that passed with second meiotic divisions giving many spermatids which transformed into spermatozoa in the lumen of the seminiferous tubules. Sertoli cells were pyriform cells with slightly eosinophilic cytoplasm and one basal nucleus. During the non- breeding seasons, the diameter of the seminiferous tubules reached 102.94 + 1..83 µm and the mean number of Sertoli cells was 1.79 + 0.16 /spermatocyst. During the breeding season, the diameter of the seminiferous tubules was 124.78 + 2.32 µm and the mean number of Sertoli cells was 3.01 + 0.14/ spermatocyst.

The present work was conducted to highlight the relationship between the external morphology of O. niloticus and the histomorphological changes of the testes during the breeding and the non breeding seasons. A total of 58 male fishes of O. niloticus were used in this investigation. The males showed bright black coloration on the dorsal and lateral parts of their body and red colour on the ventral part of their body and head during the breeding season. Testes were paired long narrow structure of approximate equal size, locating in the posterior body cavity, attached to the dorsal body wall by mesorchium. During the non-breeding season, the testes were small, thread- like and dull white in colour. During the breeding season, testes were pinkish in colour and increased in weight. The testis was covered with a capsule consisting of few collagenous, elastic fibers. Testicular parenchyma consisted of branched seminiferous tubules and interstitial tissue. The seminiferous tubules were lined with spermatogenic and Sertoli cells. Seminiferous tubules were made up of spermatocysts. During spermatogenesis, primary spermatogonia proliferated to form secondary spermatogonia which divided mitotically to form primary spermatocytes. The later underwent meiotic divisions to form secondary spermatocytes that passed with second meiotic divisions giving many spermatids which transformed into spermatozoa in the lumen of the seminiferous tubules. Sertoli cells were pyriform cells with slightly eosinophilic cytoplasm and one basal nucleus. During the non- breeding seasons, the diameter of the seminiferous tubules reached 102.94 + 1..83 µm and the mean number of Sertoli cells was 1.79 + 0.16 /spermatocyst. During the breeding season, the diameter of the seminiferous tubules was 124.78 + 2.32 µm and the mean number of Sertoli cells was 3.01 + 0.14/ spermatocyst.