الفهرس 
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Abstract
6) Summary and Conclusion
The importance of the early diagnosis of bovine tuberculosis is due to that it is widly spread in the world. It is considered a highly zoonotic disease between man and animal, due to the highly economic losses in the world. In addition to the highly spreading of this diseases in the developing countery.
Therefore this study concerned with the following items :-
1- Inspection of 3500 cattle with different ages from 3 Governorates of Egypt (Gharbia, Ismalia and Mansora) were tested by using single comparative intradermal tuberculin skin test ( SCIDT ) and the positive reactors were (80) out of 3500 tested animals (2.3%) .
2- The positive reactors were slaughtered in the abattoir of these different Governorates and the PM examination for these animals, revealed VL in 50 animals (62.5%) and the reminder had NVL 30 animals (37.5%). After application of post mortem finding it was cleared that (pulmonary, digestive, mixed and generalized infection) were recorded as follow 19 (23.8%), 11(13.8%), 16 (20%) and 4 (5 %), respectively.
3- In age of less than 2 years it was recorded that , the generalized, pulmonary, digestive and mixed VL were zero (zero%), 4 (20%), 3 (15%) and 3 (15%) ,respectively out of 20 animals. In 2-4 years, the generalized, pulmonary, digestive and mixed VL were 1(4%), 5 (20%), 3(12%) and 5 (20%) ,respectively out of 25 animals. In age of more than 5 years, the generalized, pulmonary, digestive and mixed VL were 4 (5%), 19 (23.8%), 11(13.8%) and 16 (20%) ,respectively.
4- Bacteriological examination of tested samples revealed the recovery of 44 (55%) bacterial isolates. Out of these isolates 40(50%) were identified as M. bovis and 2 (2.5%) isolates were unidentified rapid growers and also 2 (2.5%) isolates were unidentified slow growers pigmented. The Bacteriological examination showed that M.Bovis isolates from slaughtered cattle reactors showed VL of generalized ,pulmonary, digestive and mixed were 4(100%), 16(84.2%), 7(63.6%) and 13 (81.3%) ,respectively. While isolates showed unidentified rapid growers were 0(0%), 0(0%), 2(18.2%) and zero (0%) ,respectively and isolates showed unidentified slow growers pigmented were 0(0%), 0(0%), 2(18.2%) and zero (0%) ,respectively. On the other hand, the total results of bacteriological isolates from slaughtered cattle reactors showed NVL were negative.
5- Culture and sensitivity testing the isolates was done by using MODS assay for antituberculous drugs (Rifampecin- Ethambutol- Isoniazid- Streptomycin). The results of the sensitivity test were 77.2%, 72.7%, 45.5%, 40.9%, respectively. The result suggests that M. bovis is highly sensitive to Rifampecin and Ethambutol.
6- BACTEC MGIT 960 TM system was used for recovery of mycobacteria and compared it with conventional culture method (L.J.). The recovery rate of BACTEC MGIT 960 TM system was 55 %, while in case of L.J. medium was 50 %. The mean time for detection of mycobacteria was 12-17 days and 24-32 days for BACTEC MGIT 960 TM system and L.J. medium, respectively. While the contamination rate with BACTEC MGIT 960 TM system was 5 % and 6.3 % in L.J. medium.
7- It is possible to prepare ST-CF antigen from M. bovis by recent techniques and use it for diagnosis of bovine tuberculosis in comparison with bovine PPD by measuring antibodies using ELISA test on the sera of the positive tuberculin reactor cattle , positive ELISA results were obtained with 45 (90%) animals have visible lesions by using ST-CF as coating antigen while by using bovine PPD ELISA positive results were obtained with 44 (88%). While the animals that have non visible lesions, positive ELISA results were obtained with 9 (30%) animals with ST-CF while by using bovine PPD ELISA positive results were obtained with 8 (26.6%) animals.
The ELISA test showed higher sensitivity and specificity on using ST-CF as coating antigen (90%), (70.8%) than in case of using bovine PPD as coating antigen (88%) (73.3%). The positive predictive value of the ELISA test was (83.3%) in case of ST-CF, while it was (84.6%) in case of bovine PPD as coating antigens. Also the negative predictive value was (80.8%),(78.6%) for ST-CF and bovine PPD respectively. And lastly the accuracy index of ELISA test was (82.6%) and also for ST-CF and bovine PPD respectively.
8- The PCR assay was performed on selected 10 tissues samples from the positive tuberculin reactors ,eight of them were from VL and two from NVL,the results of PCR assay showed that all of them revealed positive results to the PCR test
.
Conclusion
• The BACTEC MGIT 960TM system is rapid method for the recovery of mycobacteria from clinical specimens.
• Short term culture filtrate antigens (ST-CF) elicited strong humeral immune response. Therefore may be useful as specific antigen for diagnosis of bovine tuberculin by measuring humeral immune response using ELISA.
• The PCR technique is significantly faster and simpler than conventional mycobacteriological methods for the routine differential identification of culture of M. bovis and M. Tuberculosis.
6) Summary and Conclusion
The importance of the early diagnosis of bovine tuberculosis is due to that it is widly spread in the world. It is considered a highly zoonotic disease between man and animal, due to the highly economic losses in the world. In addition to the highly spreading of this diseases in the developing countery.
Therefore this study concerned with the following items :-
1- Inspection of 3500 cattle with different ages from 3 Governorates of Egypt (Gharbia, Ismalia and Mansora) were tested by using single comparative intradermal tuberculin skin test ( SCIDT ) and the positive reactors were (80) out of 3500 tested animals (2.3%) .
2- The positive reactors were slaughtered in the abattoir of these different Governorates and the PM examination for these animals, revealed VL in 50 animals (62.5%) and the reminder had NVL 30 animals (37.5%). After application of post mortem finding it was cleared that (pulmonary, digestive, mixed and generalized infection) were recorded as follow 19 (23.8%), 11(13.8%), 16 (20%) and 4 (5 %), respectively.
3- In age of less than 2 years it was recorded that , the generalized, pulmonary, digestive and mixed VL were zero (zero%), 4 (20%), 3 (15%) and 3 (15%) ,respectively out of 20 animals. In 2-4 years, the generalized, pulmonary, digestive and mixed VL were 1(4%), 5 (20%), 3(12%) and 5 (20%) ,respectively out of 25 animals. In age of more than 5 years, the generalized, pulmonary, digestive and mixed VL were 4 (5%), 19 (23.8%), 11(13.8%) and 16 (20%) ,respectively.
4- Bacteriological examination of tested samples revealed the recovery of 44 (55%) bacterial isolates. Out of these isolates 40(50%) were identified as M. bovis and 2 (2.5%) isolates were unidentified rapid growers and also 2 (2.5%) isolates were unidentified slow growers pigmented. The Bacteriological examination showed that M.Bovis isolates from slaughtered cattle reactors showed VL of generalized ,pulmonary, digestive and mixed were 4(100%), 16(84.2%), 7(63.6%) and 13 (81.3%) ,respectively. While isolates showed unidentified rapid growers were 0(0%), 0(0%), 2(18.2%) and zero (0%) ,respectively and isolates showed unidentified slow growers pigmented were 0(0%), 0(0%), 2(18.2%) and zero (0%) ,respectively. On the other hand, the total results of bacteriological isolates from slaughtered cattle reactors showed NVL were negative.
5- Culture and sensitivity testing the isolates was done by using MODS assay for antituberculous drugs (Rifampecin- Ethambutol- Isoniazid- Streptomycin). The results of the sensitivity test were 77.2%, 72.7%, 45.5%, 40.9%, respectively. The result suggests that M. bovis is highly sensitive to Rifampecin and Ethambutol.
6- BACTEC MGIT 960 TM system was used for recovery of mycobacteria and compared it with conventional culture method (L.J.). The recovery rate of BACTEC MGIT 960 TM system was 55 %, while in case of L.J. medium was 50 %. The mean time for detection of mycobacteria was 12-17 days and 24-32 days for BACTEC MGIT 960 TM system and L.J. medium, respectively. While the contamination rate with BACTEC MGIT 960 TM system was 5 % and 6.3 % in L.J. medium.
7- It is possible to prepare ST-CF antigen from M. bovis by recent techniques and use it for diagnosis of bovine tuberculosis in comparison with bovine PPD by measuring antibodies using ELISA test on the sera of the positive tuberculin reactor cattle , positive ELISA results were obtained with 45 (90%) animals have visible lesions by using ST-CF as coating antigen while by using bovine PPD ELISA positive results were obtained with 44 (88%). While the animals that have non visible lesions, positive ELISA results were obtained with 9 (30%) animals with ST-CF while by using bovine PPD ELISA positive results were obtained with 8 (26.6%) animals.
The ELISA test showed higher sensitivity and specificity on using ST-CF as coating antigen (90%), (70.8%) than in case of using bovine PPD as coating antigen (88%) (73.3%). The positive predictive value of the ELISA test was (83.3%) in case of ST-CF, while it was (84.6%) in case of bovine PPD as coating antigens. Also the negative predictive value was (80.8%),(78.6%) for ST-CF and bovine PPD respectively. And lastly the accuracy index of ELISA test was (82.6%) and also for ST-CF and bovine PPD respectively.
8- The PCR assay was performed on selected 10 tissues samples from the positive tuberculin reactors ,eight of them were from VL and two from NVL,the results of PCR assay showed that all of them revealed positive results to the PCR test
.
Conclusion
• The BACTEC MGIT 960TM system is rapid method for the recovery of mycobacteria from clinical specimens.
• Short term culture filtrate antigens (ST-CF) elicited strong humeral immune response. Therefore may be useful as specific antigen for diagnosis of bovine tuberculin by measuring humeral immune response using ELISA.
• The PCR technique is significantly faster and simpler than conventional mycobacteriological methods for the routine differential identification of culture of M. bovis and M. Tuberculosis.