Detection of Salmonella spp. by Traditional and PCR Assays in Raw Milk, Maysan, Iraq.

Salmonella spp are characterized as rod- shaped, motile, gram- negative bacteria which has the ability to infect animals and human. Salmonella spp occasionally causes sickness while in most cases not lead to severe symptoms. Analyzing milk for Salmonella spp. is not routine but traditional culture methods are used to evaluate the health condition of the dairy products. However, the antibody-based and nucleic-acid- based methods are practical for identifying Salmonella spp. Therefore, this research was designed to evaluate the use of traditional culture methods and PCR in detection of the presence of Salmonella spp. in raw milk samples in, Maysan Iraq. A total number of 130 raw milk samples collected from Maysan Iraq. All the samples were analyzed for the presence of Salmonella spp. using traditional culture method and polymerase chain reaction (PCR). The culture method used in this experiment were done by using pre-enrichment, enrichment, selective plating and biochemical tests. The results of this traditional technique were compared with the results obtained from PCR method. The PCR was performed using a 284bp sequence of the invA gene. The results showed that 8 (7.07%) of samples were identified as salmonella positive using traditional culture technique but 14 (12.3%) samples were detected as salmonella positive by PCR method. The results of the current research revealed that the traditional culture based methods are generally time costuming and labor intensive but the development of new rapid methods including DNA based methods such as PCR are more sensitive and have dramatically decreased the time necessary for the detection of bacteria.

Ovine Pasteurellosis Vaccine: Assessment of the Protective Antibody Titer and Recognition of the Prevailing Serotypes.

Sheep husbandry is considered one of the most important activities in the socio-economic development in the Middle East region, especially in Iraq and Islamic Republic of Iran (IRI). Therefore this study was designed to evaluate the level of ovine pasteurellosis vaccine protective antibody titer and identification of the prevailing serotypes in Iraq (Basrah, Baghdad, Tikrit, Mosul, Erbil). The vaccine was made from pasteurella multosida Bio-type A and the serotypes of Mannheimia haemolytica. This investigation was performed from September 2021 to January 2022, in Iraq. Sheep blood sera samples were obtained from control unvaccinated and vaccinated sheep after 14, 21 and 28 days post vaccination. The results showed that out of 319 sheep blood sera samples which were evaluated using indirect Haemagglutination (IHA) test to detect Mannheimia haemolytica serotypes, the high prevalence (100 %) of M. haemolytica A2 was found in all the five study regions area, while 96.5 % was M. haemolytica A7 and 88.1 % was M. haemolytica A1. The level of antibody titer was measured by specific serum antibody titer of pasteurella multosida Bio-type A. The results revealed that out of 268 vaccinated blood sera samples the overall antibody titer were 12 (3.8 %), 16 (5%) and 17 (5.3 %) for protective antibody titer of 1:160, 1:80 and 1:40 respectively and for antibody titer of 1:20 were 15 (4.7%) and for antibody titer of 1:10 were 17 (5.3 %), whereas the antibody titer in the control group was 4 (7.8 %). The result of this study indicated that the vaccine administered has limited protective power against pasteurella multocida Bio-type A which lead to researchers for further study on identification of specific strain of pasteurella multosida and development of multivalent vaccine including the most prevalent pasteurella serotypes.