Abstract:
Mastitis of cattle causes a massive economic loss worldwide. The treatment of mastitis is generally
considered to be limited because of low cure rates and the cost of milk discarded during the
withdrawal period. The criticism of use of antibiotics to treat mastitis is that it leads to development
of resistant bacteria and presence of residual effect of antibiotic in milk. Therefore, now many
researchers are turning to find non-antibiotic approaches in order to reduce the use of antibiotics.
In the traditional veterinary medicine, medicinal herbs are used to treat animal diseases. This is
believed to be natural and safe therapeutic methods. In this in vitro study, the Black seed (Nigella
sativa) oil was examined for its antibacterial activity against one of the most common mastitis
pathogen, Streptococci, in order to develop an herbal remedy for Streptococcus mastitis as a
substitute for antibiotics. This is the first report demonstrating this oil on mastitis causing
Streptococci. In this study, Streptococci organisms isolated from 40 clinicallyinfected milk samples
were investigated. All the organisms tested were susceptible and the antibacterial effect of Black
seed oil on Streptococci organisms was very significant as evidenced by the inhibition zone sizes
obtained. In conclusion, the antibacterial effect of this seed on Streptococci, which causing
mastitis was statistically significant and this study suggesting that Black seed oil can be used as
antibacterial agent targeting on Streptococcus mastitis.
