Identification and antibiogram study of bacterial species isolated from milk samples of different locations in Bangladesh

Abstract

Cow's milk containing pathogenic bacteria is an important threat to the consumers. The objectives of the present study were to identify the bacterial agents of public health importance in milk samples (n=35) of different locations and to determine their sensitivity to different antibiotics. The milk samples were collected and transported aseptically and subsequently allowed for culture in bacteriological media, Gram's staining and biochemical tests for the identification of bacterial species. The bacteria identified were Staphylococcus aureus, Escherichia coli and Salmonella typhi, and their prevalence, in case of vendor milk specimens (n=28), were 96.43%, 53.57% and 35.71% respectively, and of brand milk specimens (n=7), were 42.86 %, 28.57% and 0%, respectively. This suggests that cautionary measures should be taken for quality milk production and consumption. The antibiotic sensitivity test was done by disc diffusion method and the average inhibition zones, in case of Staphylococcus aureus, were 32 mm for oxytetracycline, 26 mm for amoxicillin, 35 mm for ciprofloxacin, 27 mm for cefotaxime, 30 mm for ceftriaxone, 30 mm for azithromycin, and 26 mm for erythromycin; in case of Escherichia coli, were 5 mm for oxytetracycline, 9 mm for amoxicillin, 22 mm for ciprofloxacin, 30 mm for cefotaxime, 31 mm for ceftriaxone, 15 mm for azithromycin, and 0 mm for erythromycin; in case of Salmonella typhi., were 25 mm for oxytetracycline, 24 mm for amoxicillin, 38 mm for ciprofloxacin, 31 mm for cefotaxime, 34 mm for ceftriaxone, 24 mm for azithromycin, and 0 mm for erythromycin. Therefore, ciprofloxacin and ceftriaxone may be the antibiotics of first choice, and cefotaxime and azithromycin may be the second choice among the test antibiotics for the treatment of illness caused by these bacteria.

Prevalence and antibiotic resistance of <Salmonella> spp. in South Punjab-Pakistan

“…Bangladesh as a region in subcontinent was not an exception for higher Salmonella prevalence where the presence of S. typhi was found to be 35.17% in vendor’s milk. More studies confirmed these results showing Salmonella prevalence to the tune of 9.5% and 4.2% [21,36,37] This variation justified high prevalence of Salmonella in various South Asian regions especially those located in subcontinent i.e. Pakistan and India because cultural, atmospheric and social conditions were quite the same therefore we might have witnessed the prevalence level being reported from these areas to be more or less similar.…”

“…Similar results were presented by Addis et al [20] who reported Salmonella at 10.76% ( n =21/195) either from milk or feces samples. Similarly, 35.71% milk samples were found to be positive for S. typhi in Bangladesh [21]. Apart from Southern Punjab regions, more reports are available to signify the overwhelming effects of S. enteritidis among a number of population groups.…”

Prevalence study of Salmonella spp. in milk and milk products

“…In a study, Kaushik et al (2014) observed presence of Salmonella in market milk samples in Patna, Bihar. Tangri et al (2014) and Bharathy et al (2015) found the presence of Salmonella to be 9.5% and 4.2% respectively, while Munsi et al (2015) found the presence of S. typhi to be 35.17% in vendor's milk in Bangladesh. The prevalence of pathogenic zoonotic and nonzoonotic Salmonella viz S. typhi, S. enteric, S. anatum and S. enteric serovar arizonae have been reported by different workers from time and again (Busani et al, 2004;Chye et al, 2004;Munsi et al, 2015;Lubote et al, 2014).…”

Detection of Multi–drug Resistant Salmonella From Milk and Meat in Bangladesh

“…in milk samples. However, Munsi et al (2015) reported 35.71 % milk samples to be positive for Salmonella typhi in vendor milk and 0 % in brand milk. We have collected milk aseptically from teat directly and the prevalence of Salmonella spp.…”