Bacteriophage named as SAL-PG (Salmonella bacteriophage), specific to Salmonella pullorum and Salmonella gallinarum was isolated by an enrichment method directly from waste water near to poultry farm. For the isolation of phage 4.5 ml water sample, 0.5 ml of 10X Nutrient Broth and 0.5 ml of log phage bacteria were mixed well and incubated at 37 0 C for overnight followed by centrifugation at 10,000 rpm for 10 minutes. The presence of bacteriophage was observed by spot test over the bacterial lawn of and plaque assay. The host range of the isolated bacteriophage was determined by spot test using 12 different bacterial isolates. The phages were found to infect Salmonella pullorum, Salmonella gallinarum and Salmonella typhimurium and produced clear plaque on these Salmonella serovars. The bacteriophage was able to survive in wide range of pH between 2 to 9 and resistant at 60°C for 1 hour. More than 50% phages were readily adsorbed to the host bacteria. The restriction enzyme analysis showed that the phage DNA possess restriction site for TaqαI, HindIII and BstYI; but no restriction site for XhoI and BstEII as these two enzymes failed to digest the phage DNA. The characterizations of the bacteriophage would be helpful in establishing a basis for adopting the application of the most effective bacteriophage treatment to control these poultry bacteria.

Foot and Mouth Disease (FMD) is one of the highly contagious diseases of domestic and wild animals of many countries of the world including Bangladesh. The present study was undertaken to detect currently circulating FMD virus (FMDV) in Bangladesh using BHK-21 cell line, and the FMDV were typed using RT-PCR. The viruses induced characteristics cytopathic effects in BHK-21 cell lines, for examples, rounding, swelling, breaking down of intercellular bridge and cell death. Out of 151 clinical samples collected from different districts of Bangladesh, 85(56.29%) were successfully adapted in BHK-21 cell line, and were analyzed using FMDV type specific primers. Among these 85 BHK-21 adopted virus, 71(83.52%) were found as positive for FMD virus by RT-PCR; of which, 31 (36.47%) were positive for type A, 26 (30.58%) for type O, and 10 (11.76%) for type Asia 1. Only 4 (4.70%) samples were found as positive for mixed infection having Type A and Asia 1 FMDV. All the FMDV originated from Tangail (n=7) and Rajshahi (n=6) districts were found as positive for FMDV while 71.42% (n=14/36) samples of Mymensingh district were positive for FMDV. The FMDV identified in this study could now be used for effective vaccine development to control the disease in Bangladesh.

Hemorrhagic septicemia (HS) is an acute septicemic disease that primarily affects cattle and buffaloes. The disease is caused by Pasteurella multocida sero types B:2 and E:2. The objective of this study was to isolate P. multocida from clinical cases and to confirm its identity using polymerase chain reaction (PCR) based approach. Clinical samples of two suspected cases of haemorrhagic septicemia of cattle and buffalo from Mymensingh and Rajshahi districts respectively were collected. Two isolates were isolated from these suspected cases and primarily identified as P. multocida based on morphological study, staining properties, and cultural and biochemical characteristics. The isolates were confirmed initially as P. multocida at genus level by PCR using genus specific primers. Later, the isolates were confirmed as P. multocida type B, the causal agent of haemorrhagic septicemia, by PCR with primers specific for P. multocida type B. These isolated organisms can be used as vaccine candidate for the production of effective vaccine against haemorrhagic septicemia.Progressive Agriculture 27 (2): 175-179, 2016

The economic consequences of an outbreak of Foot and Mouth Disease (FMD) in Bangladesh is devastating. A sensitive, reliable and rapid diagnosis is crucial for the effective control of FMD. The present research was conducted for quick molecular detection and adaptation of FMD virus (FMDV) in BHK-21 (Baby Hamster Kidney) cell line. A two-step RT-PCR method was applied for the detection of the FMDV. Without prior adaption into BHK-21 cell culture, it is difficult to detect FMDV directly from the field samples by RT-PCR method. Samples were collected from the tongue epithelium (N=19) and inter digital tissues (N=4) of the suspected animals in Sujanagar, Bera, Santhia of Pabna district and Kotowali, Trishal of Mymensingh districts of Bangladesh during the year 2014. BHK-21 cell subculture was done from a previously cultured bottle containing BHK-21 cells. Prepared inocula were inoculated into BHK-21 cell culture and incubated at 37ºC for 24 h. After 36 h, cytopathic effects (CPE) were observed in BHK-21 cell line characterized by rounding and flattening of the cells, multinucleated giant cells formation, breaking down of the intracellular bridges and finally cell death indicated the presence of FMDV. Clear infectious BHK-21 cell culture fluid was collected and preserved at -20ºC temperature for virus detection by RT-PCR with serotype specific primers. Viral RNA was extracted from the clear infectious cell culture fluid for cDNA synthesis and used for PCR. Out of 23 samples tested, 3(13.04%) were positive for FMDV serotype A. The findings of this study can be helpful for the selection of vaccine having specific FMDV type, and it may help in controlling FMD in Bangladesh.Progressive Agriculture 27 (1): 64-69, 2016