The present study was conducted to highlight the relationship between the external morphology of female O.niloticus and the histomorphological changes of the ovaries during different seasons of the year. A total of 58 female fishes of O.niloticus were used in this investigation. The external features of females didn't show any seasonal variations. Ovaries were paired elongated, cylindrical structure of approximate equal size, located in the posterior body cavity, ventral to the swim bladder and attached to the dorsal body wall by mesovarium. During the non-breeding season, ovaries were small, yellowish red in colour and occupied small portion of the body cavity. While during the breeding season, ovaries were extremely long and wide, yellowish in colour and more vascularized. They occupied almost the entire body cavity. The ovary of O. niloticuis was covered by a thick capsule during the non-breeding season, but became thin and vascular during the breeding period. Six arbitrary stages of oogenesis process had been established among the ovarian follicles; oogonia (stagel), chromatine nucleolus stage (stage 2), perinucleolar stage (stage 3), yolk vesicle stage (stage 4), yolk globule stage (stage 5) and mature stage (stage 6). During the non-breeding season, the ovaries were filled with previtellogenic oocytes in perinucleolus stage. Oocytes in the oogonium and chromatin nucleolus stages were abundant; the oogonia reached 10+1.5/ UA and the chromatin nucleolus reached 9.8+1.4 / UA during the non-breeding season. While during the breeding season, the ovaries were in a condition of active vitellogenesis and mature oocytes increased both in number (4.0+0.5 / UA) and in diameter (806.0+11.0 µm). Morphometric studies revealed significant differences in the length, diameter and weight of the ovaries of O.niloticus during breeding and non-breeding seasons.

The present study was conducted to highlight the relationship between the external morphology of female O.niloticus and the histomorphological changes of the ovaries during different seasons of the year. A total of 58 female fishes of O.niloticus were used in this investigation. The external features of females didn't show any seasonal variations. Ovaries were paired elongated, cylindrical structure of approximate equal size, located in the posterior body cavity, ventral to the swim bladder and attached to the dorsal body wall by mesovarium. During the non-breeding season, ovaries were small, yellowish red in colour and occupied small portion of the body cavity. While during the breeding season, ovaries were extremely long and wide, yellowish in colour and more vascularized. They occupied almost the entire body cavity. The ovary of O. niloticuis was covered by a thick capsule during the non-breeding season, but became thin and vascular during the breeding period. Six arbitrary stages of oogenesis process had been established among the ovarian follicles; oogonia (stagel), chromatine nucleolus stage (stage 2), perinucleolar stage (stage 3), yolk vesicle stage (stage 4), yolk globule stage (stage 5) and mature stage (stage 6). During the non-breeding season, the ovaries were filled with previtellogenic oocytes in perinucleolus stage. Oocytes in the oogonium and chromatin nucleolus stages were abundant; the oogonia reached 10+1.5/ UA and the chromatin nucleolus reached 9.8+1.4 / UA during the non-breeding season. While during the breeding season, the ovaries were in a condition of active vitellogenesis and mature oocytes increased both in number (4.0+0.5 / UA) and in diameter (806.0+11.0 µm). Morphometric studies revealed significant differences in the length, diameter and weight of the ovaries of O.niloticus during breeding and non-breeding seasons.

The effect of nisin on the survival of enterotoxingenic methicillin-resistant Staph. aureus (MRSA) was evaluated using different concentrations of nisin (0.00, 100 and 200 IU/ml) in a laboratory prepared sterile milk and inoculated with the previously isolated and identified MRSA to yield a concentration of 1x107 cfu/ml. The inoculated sterile milks were kept at room temperature (20±2ºC) and refrigerator temperature (4±2ºC). MRSA counts were determined using Oxacillin Resistance Screen Agar Base (ORSAB) supplement with two antibiotics-oxacillin at (2 mg/L) and polymyxin B (50.000 IU/L). ORSAB and pH value were determined every twelve hours. MRSA strains couldn't be detected after 96 and 72 h in the samples of sterile milk containing nisin in concentrations of 100 and 200 IU/ml, while, in the control sample the MRSA survived till the end of the 96 h of storage at room temperature. Moreover, MRSA failed to be detected after 48 and 24 h in the samples of sterile milk containing nisin in concentrations of 100 and 200 IU/ml and storaed at refrigerator temperature, respectively. Ice cream was prepared at the laboratory to study the effect of ground cinnamon in concentrations of 0.3 and 0.6% on the growth and survival of enterotoxingenic MRSA a concentration of 2x107 cfu/ml at freezing (-4±2ºC) and deep freezing (-18±2ºC) temperatures. The obtained results showed that the advantage of using 0.6% is better than using of 0.3% of ground cinnamon.

The effect of nisin on the survival of enterotoxingenic methicillin-resistant Staph. aureus (MRSA) was evaluated using different concentrations of nisin (0.00, 100 and 200 IU/ml) in a laboratory prepared sterile milk and inoculated with the previously isolated and identified MRSA to yield a concentration of 1x107 cfu/ml. The inoculated sterile milks were kept at room temperature (20±2ºC) and refrigerator temperature (4±2ºC). MRSA counts were determined using Oxacillin Resistance Screen Agar Base (ORSAB) supplement with two antibiotics-oxacillin at (2 mg/L) and polymyxin B (50.000 IU/L). ORSAB and pH value were determined every twelve hours. MRSA strains couldn't be detected after 96 and 72 h in the samples of sterile milk containing nisin in concentrations of 100 and 200 IU/ml, while, in the control sample the MRSA survived till the end of the 96 h of storage at room temperature. Moreover, MRSA failed to be detected after 48 and 24 h in the samples of sterile milk containing nisin in concentrations of 100 and 200 IU/ml and storaed at refrigerator temperature, respectively. Ice cream was prepared at the laboratory to study the effect of ground cinnamon in concentrations of 0.3 and 0.6% on the growth and survival of enterotoxingenic MRSA a concentration of 2x107 cfu/ml at freezing (-4±2ºC) and deep freezing (-18±2ºC) temperatures. The obtained results showed that the advantage of using 0.6% is better than using of 0.3% of ground cinnamon.

Two hundred and forty random samples of raw milk including cow's (90), buffalo's (90), sheep's (30) and goat's milk (30) were collected from dairy farms, dairy shops and street vendors in Assiut city. These samples were examined for the prevalence of Nocardia spp. using two selective media: Nocardia and Bushnell-Hass media. The recorded data revealed that 43 (47.8%), 39 (43.3%), 16 (53.3%) and 20 (66.7%) of the examined cow's, buffalo's, sheep's and goat's milk samples, respectively were contaminated with Nocardia spp. on Nocardia medium. However, the incidence of Nocardia spp. on Bushnell-Hass medium was 37 (41.1%), 39 (43.3%), 15 (50%), and 15 (50%) in the same samples, respectively. The highest Nocardia positive samples were from goat's and sheep's milk. Different counts of Nocardia spp. from milk samples on both media were recorded. N.asteroides was the predominant species, it could be isolated in percentages of 25.4 and 30.2% on Nocardia and Bushnell-Hass medium respectively, other nocardia species were isolated in different percentages. The public health significance of the organisms and the precautions which should be taken to control this organism in dairy industry as well as the recommended sanitary measures, were also discussed.

Two hundred and forty random samples of raw milk including cow's (90), buffalo's (90), sheep's (30) and goat's milk (30) were collected from dairy farms, dairy shops and street vendors in Assiut city. These samples were examined for the prevalence of Nocardia spp. using two selective media: Nocardia and Bushnell-Hass media. The recorded data revealed that 43 (47.8%), 39 (43.3%), 16 (53.3%) and 20 (66.7%) of the examined cow's, buffalo's, sheep's and goat's milk samples, respectively were contaminated with Nocardia spp. on Nocardia medium. However, the incidence of Nocardia spp. on Bushnell-Hass medium was 37 (41.1%), 39 (43.3%), 15 (50%), and 15 (50%) in the same samples, respectively. The highest Nocardia positive samples were from goat's and sheep's milk. Different counts of Nocardia spp. from milk samples on both media were recorded. N.asteroides was the predominant species, it could be isolated in percentages of 25.4 and 30.2% on Nocardia and Bushnell-Hass medium respectively, other nocardia species were isolated in different percentages. The public health significance of the organisms and the precautions which should be taken to control this organism in dairy industry as well as the recommended sanitary measures, were also discussed.

The chick performance, carcass traits and some blood biochemical parameters of Japanese quails fed high energy diet containing different protein levels were studied for 42 days. Sixty quail chicks at hatch (average weight 7.02 g ± 0.12) were randomly distributed into five experimental groups (12 chicks/each). Quails in the five groups were fed ad libitum on the respective isocaloric experimental diets (3200kcal ME/kg diet) containing five dietary protein levels (18, 20, 22, 24, 26 %). The growth performance, carcass characteristics and some blood biochemical parameters were assessed. The results showed that, quails fed on high energy diets containing 22, 24 % protein in the third and fourth groups achieved significantly (P0.05) better results, and recorded highest gains (188.0 & 189.4 g, respectively) with lowest feed intake. Highest weight gain averages with greatest values of feed conversion (2.84 & 2.71) were recorded in the third and fourth groups of quails, respectively. Dressed carcass as a percentage of live body weight was maximum in quails offered high protein diets in the fourth and fifth groups (73.21 & 73.06%), while the lowest were recorded in the first three groups fed low protein diets (68.12, 68.45 & 68.19 %, respectively). Dietary protein levels had no significant (P0.05) effect on the internal organ weights. Uric acid, calcium and inorganic phosphorous were increased significantly (P0.05) with increasing dietary protein levels, while had no significant effect on serum triglycerides, cholesterol and glucose. It could be concluded that, quails fed on diet having 3200kcal ME/kg with 22 % crude protein, supplemented with limiting amino acids, recorded the best results in weight gain and feed conversion, in addition to economical feed efficiency.

The chick performance, carcass traits and some blood biochemical parameters of Japanese quails fed high energy diet containing different protein levels were studied for 42 days. Sixty quail chicks at hatch (average weight 7.02 g ± 0.12) were randomly distributed into five experimental groups (12 chicks/each). Quails in the five groups were fed ad libitum on the respective isocaloric experimental diets (3200kcal ME/kg diet) containing five dietary protein levels (18, 20, 22, 24, 26 %). The growth performance, carcass characteristics and some blood biochemical parameters were assessed. The results showed that, quails fed on high energy diets containing 22, 24 % protein in the third and fourth groups achieved significantly (P0.05) better results, and recorded highest gains (188.0 & 189.4 g, respectively) with lowest feed intake. Highest weight gain averages with greatest values of feed conversion (2.84 & 2.71) were recorded in the third and fourth groups of quails, respectively. Dressed carcass as a percentage of live body weight was maximum in quails offered high protein diets in the fourth and fifth groups (73.21 & 73.06%), while the lowest were recorded in the first three groups fed low protein diets (68.12, 68.45 & 68.19 %, respectively). Dietary protein levels had no significant (P0.05) effect on the internal organ weights. Uric acid, calcium and inorganic phosphorous were increased significantly (P0.05) with increasing dietary protein levels, while had no significant effect on serum triglycerides, cholesterol and glucose. It could be concluded that, quails fed on diet having 3200kcal ME/kg with 22 % crude protein, supplemented with limiting amino acids, recorded the best results in weight gain and feed conversion, in addition to economical feed efficiency.

A side effect of cyclophosphamide (CP), an alkylating agent widely used to treat tumors and autoimmune disorders is the alteration of male reproductive function. CP is extremely dangerous to the germinal epithelium and damage to spermatogenesis. High doses can cause azoospermia which can result infertility in humans. This study is focused on the evaluation of toxicological effect of cyclophosphamide on male rat testis and the possible reversibility of these toxic effects. Thirty adult male rats were divided into three groups: vehicle-treated (control), CP-treated and rehabilitated groups. CP was administrated intraperitoneally (100mg/kg/week) for five successive weeks, and semithin sections from testicular tissue were prepared and examined after last injection (treated group) and six weeks later (rehabilitated group). A quantitative morphometric study and statistical analysis were applied for accurate and efficient assessment of spermatogenic impairment induced by CP. The CP treated group showed various morphological alterations in the testis such as reduction in the size and distortion in the shape of the seminiferous tubules with degeneration and vacuolation in spermatogonia, spermatocytes and spermatids associated with marked interstitial oedema. In addition, the CP induced significant decreases in volume proportion, diameter and epithelial height of the seminiferous tubules together with a significant reduction in the number of different germ cells in the treated animals. Interestingly, spermatogonia A appeared to be target cells for the damaging effect of CP in the testis that presented severe degenerative changes in structure along with significant reduction in number in the treated group animals. Furthermore, the number of primary spermatocytes and round spermatids decreased significantly in CP- treated group. The Sertoli and Leydig cells, however, appeared to be less affected to CP toxicity; exhibiting insignificant decrease in number as well as less morphological alterations. The Interstitial spaces of treated group animals showed a highly significant increase in its volume proportion, when compared to the control animals. Meanwhile, the rehabilitated group showed significant increases for aforementioned variables in comparison to the CP- treated group, associated with reversal of morphological changes towards normalcy. Based on the results from the present study it is concluded that the morphological alterations induced by CP toxicity were further substantiated by morphometric findings in the testicular tissue of rat. A direct toxicity of CP to the number and quality of spermatogenic compartment may be considered as one of the mechanisms of action of CP in producing the abnormal and dead sperms that alter fertility. By the reversal of morphological and stereological changes towards normalcy, the role of rehabilitation is illuminated in CP induced testicular damage.

A side effect of cyclophosphamide (CP), an alkylating agent widely used to treat tumors and autoimmune disorders is the alteration of male reproductive function. CP is extremely dangerous to the germinal epithelium and damage to spermatogenesis. High doses can cause azoospermia which can result infertility in humans. This study is focused on the evaluation of toxicological effect of cyclophosphamide on male rat testis and the possible reversibility of these toxic effects. Thirty adult male rats were divided into three groups: vehicle-treated (control), CP-treated and rehabilitated groups. CP was administrated intraperitoneally (100mg/kg/week) for five successive weeks, and semithin sections from testicular tissue were prepared and examined after last injection (treated group) and six weeks later (rehabilitated group). A quantitative morphometric study and statistical analysis were applied for accurate and efficient assessment of spermatogenic impairment induced by CP. The CP treated group showed various morphological alterations in the testis such as reduction in the size and distortion in the shape of the seminiferous tubules with degeneration and vacuolation in spermatogonia, spermatocytes and spermatids associated with marked interstitial oedema. In addition, the CP induced significant decreases in volume proportion, diameter and epithelial height of the seminiferous tubules together with a significant reduction in the number of different germ cells in the treated animals. Interestingly, spermatogonia A appeared to be target cells for the damaging effect of CP in the testis that presented severe degenerative changes in structure along with significant reduction in number in the treated group animals. Furthermore, the number of primary spermatocytes and round spermatids decreased significantly in CP- treated group. The Sertoli and Leydig cells, however, appeared to be less affected to CP toxicity; exhibiting insignificant decrease in number as well as less morphological alterations. The Interstitial spaces of treated group animals showed a highly significant increase in its volume proportion, when compared to the control animals. Meanwhile, the rehabilitated group showed significant increases for aforementioned variables in comparison to the CP- treated group, associated with reversal of morphological changes towards normalcy. Based on the results from the present study it is concluded that the morphological alterations induced by CP toxicity were further substantiated by morphometric findings in the testicular tissue of rat. A direct toxicity of CP to the number and quality of spermatogenic compartment may be considered as one of the mechanisms of action of CP in producing the abnormal and dead sperms that alter fertility. By the reversal of morphological and stereological changes towards normalcy, the role of rehabilitation is illuminated in CP induced testicular damage.