Some studies on the factors of the pathogenicity of Staphylococcus aureus isolated from bovine mastitis

This work aimed to study some factors of the pathogenicity of S. aureus isolated from bovine mastitis. Holstein-Friesian cows raised in two farms in El-Bohera governorate were examined from winter 2008 through spring 2009. Clinically, 208 out of 1000 cows had mastitis. Milk samples were collected and subjected for bacteriological examination for isolation and identification of S. aureus as well as further identification of S. aureus enterotoxin A [SEA] via PCR using species specific primers. Sixty-five [31.25%] isolates of staphylococci could be isolated. Twenty-two [33.85%] of the isolates were positive for coagulase activity. Two isolates out of eight [25%] biochemically identified S. aureus were positive for SEA. As detected by PCR

Effect of sprulina platensis on the immune response of cultured oreochromis niloticus

The use of microalgae in the field of fish feeding is still operated in a small scale. This study was conducted to evaluate the effects of using the microalga Spirulina platensis powder as a feed additive in fish diets. So, we use a total number of 120 apparently healthy Oreochromis niloticus, with average body weight of fish [50 +/- 5g] were obtained from Barseek fish farm at Behera Governorate. The present work was designed to investigate the different immunostimulant effects of Spirulina on some cultured freshwater fish including serum proteins, [Lymphocytes and monocytes] as well as phagocytic activity, index and the level of antibody titer, relative level of protection. For these investigations four experimental diets were carried out by addition of Spirulina platensis powder to balanced fish diet. 1[st] group: fed on 1[st] diet which is formed of fish diet with addition of 2.5% Spirulina platensis powder to it. 2[nd] group: fed on 2[nd] diet which is formed of fish diet with addition of 5% Spirulina platensis powder to it. 3[rd] group: fed on 3[rd] diet which is formed of fish diet with addition of 10% Spirulina platensis powder to it. 4[th] group: fed on 4[th] diet which is formed of fish diet without addition of Spirulina platensis powder to it [Control group]. The most important results of this study include: 1.There was a tendency for the WBCs values had the highest values during addition of Spirulina also there was increasing in lymphocyte and monocytes in groups fed on Spirulina than the control groups. 2. Fish groups supplemented with Spirulina showed increased of phagocytic activity and phagocytic index until the 4[th] weeks from feeding Spirulina. 3. In the present work, the significant increase in albumin, globulin and total protein and increase of albumin/globulin [A/G] ratio in the groups fed on Spirulina than control group 4. The antibody titers in all Spirulina supplemented groups were highor than the control feed on basal diet where ranged between 2 +/- 0.1, 3 +/- 0.1, 4 +/- 0.3 and 4 +/- 0.3 during 1[st], 2[nd], 3[rd] and 4[th] weeks respectively and at the end of the 4[th] week, the antibody titers ranked in groups where the 10% Spirulina supplemented group come in the first rank, followed by 5% Spirulina supplemented group, then 2.5% Spirulina supplemented group while the control group came in the last rank in values. 5. The potency of bacterin was examined by calculating the relative level of protection [RLP]. In this study, we examined the disease resistance in Spirulina - treated tilapia using the tilapia pathogen Aeromonas hydrophila

Isolation and identification of ichthiophonus hoferi from cultured fish

The Icthyophonosis is a dangerous disease, the consequences of which are difficult to assess for wild populations of fish. This study aimed to throw the light on the importance of I. hoferi on fresh water fish, it dangerious effect in addition to its identification of isolation, characterization and the most important symptoms showed on naturally infected Oreochromis niloticus with I. hoferi showing deformity of vertebral column, darkening in color, sand paper appearance of skin, poor appetite listlessness. The young culture of I. hoferi on SDA t 10% bovine serum showing rupture of multinucleated bodies and release of spores through extra material discharge after 9 days. At PH 3.5 showing starting of hyphal growth after shours post-culturing the lyphae produce many branches, extending of the hyphae to grow and increase in length after 24 hours, migration of cytoplasm to the apexes of hypae after 3 days, rounding up of the apics of the hyphae after 7 days, finally all the hyphae rounding up to form sphericael hyphae terminal bodies after 10 days. Rounding up of the apics of the hyphae after 7 days, finally all the hyphae rounding up to form sphericael hyphae terminal bodies after 10 days and in old culture showing chlamydospores formation around the multinucleated bodies and extend to the test of sticked hyphae at 3 weeks

Immunological and biochemical responses in asian seabass fingerlings [lates calcarifer] vaccinated with vibrio anguillarum bacterin

Groups of apparently healthy Asian seabass fingerlings [Lates calcarifer] weighing from 20 to 30 g were immunized against vibriosis by a vaccine in the form of formalin killed bacteria of Vibrio anguillarum that originated from diseased fish. This immunization was administered by three different routes which were bath immersion, orally [by feeding] or intraperitoneal injection [IP]. Immunization process was followed with booster dose by the same routes 2 weeks after the 1[st] dose. The efficacy of this vaccination was evaluated based on immune responses [specific and non specific] and protection against bacterial challenge performed by IP inoculation with 0.1 ml of bacterial, suspension of live virulent V. anguillarum at concentration of 1.2 x 108 c /ml. Antibody titres [as specific immunity], phagocytic activity phagocytic index and serum bactericidal activity [as non-specific immunity] mortality% and relative percentage survival [RPS] as challenge indicators against V. anguillarum were determined. Also, serum: total protein, albumin and globulin contents and albumin / globulin ratio [A / G] were estimated. In the present study serum antibody titres, phagocytic activity and phagocytic index were significantly increased in different vaccinated groups after one and two weeks from the 1[st] dose of vaccine and after one week of booster dose of vaccine. Except, only one week after the 1[st] dose of vaccine, bath immersion vaccinated group showed no changes in serum antibody titres. Detection of serum bactericidal activity showed that there were significantly higher levels against V. anguillarum as marked reduced survive index [SI] in all vaccinated fish compared with controls at different sampling times. Serum bactericidal activity in oral and IP injection of vaccinated fish groups showed higher levels by significantly indicated reduced survive index [SI] more than in bath immersion vaccinated group at different sampling times. The vaccination conferred protection without any mortalities against V. anguillarum challenge as relative percentage survival [RPS] = 100% for each group of oral and IP injection vaccination. RPS in the bath immersion vaccinated group was 60% with 40% mortality, while, in control group there was no protection, where, RPS was zero and mortality was 100% Serum total protein and globulin contents were significantly increased in all vaccinated groups one and two weeks after 1[st] dose of vaccination and also one week after the booster dose. Albumin contents of serum were significantly decreased in bath immersion and oral vaccinated groups after one week from the 1[st] and booster doses of vaccination A / G ratios were significantly decreased in bath immersion and oral vaccinated groups after one week from the 1[st] and booster doses of vaccination also, A / G ratios in IP injection vaccinated groups were significantly decreased after two weeks and one week from the 1[st] and booster doses of vaccination respectively. Thus Asian seabass fingerlings gave good protective immune responses to Vibrio anguillarum vaccine when vaccinated by direct bath immersion orally or IP injection but in the two last routes it was better and marked protective immunity were recorded