Vol. 12, Issue 5 (2023)

Author(s):
Sivarama Krishna Gollapalli, Sai Chaitanya V, Lokeshwari R, Lakshmikanth K, Prabhakar Rao K and Vamshi Krishna S

Abstract:
Bovine mastitis is a dreadful disease of cattle majorly caused by Staphylococcus species. In the present study, a total of 20 Staphylococcus species were isolated from mastitis milk samples of dairy Cattle. Out of 20 samples, 10 samples were quantitatively characterized as biofilm producers. The highest density of the biofilm was recorded at 32 hrs post incubation in comparison to that of 18 hours culture. Five commonly used antibiotic drugs by the field Veterinarians (Ciprofloxacin, Amoxicillin Na, Gentamicin, Cefaperazone and Enrofloxacin) for treating the mastitis, were tested. The minimum inhibitory concentration (MIC) of the drugs has been altered between 18 hrs post incubation culture and 36 hrs post incubation culture. The sample S6 was sensitive to the drug Enrofloxacin, and the end point of the MIC is 25 µg for 18 hours culture, which has increased to 50 µg for 36 hours culture. For the drug Amoxycillin Na, the MIC required for S11 was 12.52 µg for 18 hrs culture while it was enhanced to 50 µg after 36 hrs of post incubation culture. For the drug Enrofloxacin, the MIC for S11 was 3.125 µg for 18 hrs culture and 6.25 µg for 36 hrs culture and for Ciprofloxacin it was 25 µg for 18 hrs culture and 50 µg for 36 hrs culture. The drug Ciprofloxacin against S13, the variation in MIC was reported as 3.625 µg for 18 hrs and 50 µg for 36 hrs. The S19 sample was sensitive to the drug Amoxycillin Na and the MIC for 18 hrs culture was 25 µg and for 36 hrs culture was 50 µg.. The results have proved that the MIC of antibiotics against the Staphylococcus has got altered depending on the density of the biofilm formation by the bacterium. The bacteria encased in biofilms are being protected from the action of antibiotics at therapeutic concentrations, evade the host immune responses and become a potential threat for the health communities.