Abstract:
Probiotic bacteria boost health by fighting pathogens and regulating immunity.
Many strains are derived from various sources like fermented foods and dietary
supplements. To combat antimicrobial resistance in disease prevention, probioticbased
approaches are vital. This study aimed to investigate the antagonistic effect
of locally and commercially available probiotic bacteria against bovine pathogens.
Fermented coconut water and rice water prepared in the laboratory, curd, and five
probiotic products from the market were cultured on De Man Rogosa Sharpe (MRS)
agar to obtain lactic acid bacteria (LAB). The resulting colonies were morphologically
examined, Gram stained and evaluated for inhibition of bovine mastitis pathogens
including Escherichia coli (n = 3) Staphylococci spp (n = 2), and two reference cultures of
E. coli and S. aureus, using modified disk diffusion method. All obtained colonies were
Gram-positive yielding both Gram-positive cocci and bacilli. Bacilli were isolated from
rice water whereas both bacilli and cocci were detected from curd. Fermented coconut
water comprised of cocci bacteria as similar to the commercial probiotic products. One
LAB strain from fermented coconut water and two bacterial strains, one coccus and
one bacillus from a curd sample showed inhibition zones of 17mm-23mm, 14mm, and
15mm respectively against the tested bovine pathogens. However, bacteria isolated
from the probiotic tablets did not show inhibition zones against the pathogens. This is
the first report on fermented coconut water LAB inhibiting bovine mastitis pathogens.
In conclusion, the local LAB from environmental sources is more effective against
indigenous bovine pathogens compared to market products. These can be used to
reduce disease incidence. Additional testing is in progress to identify the species of
LAB. Further studies are recommended to produce effective probiotic formulations for
use in livestock farming.
