Treatment trial of subclinical mastitis with the herb Persicaria senegalense (Polygonaceae).

The possible remedial effect of Persicaria senegalense in bovine subclinical mastitis was studied by in vitro and in vivo antimicrobial tests, using crude extracts and the leaf in different forms. The in vitro test showed that isolates of Staphylococcus aureus, Candida albicans and Corynebacterium bovis from subclinical cases and an isolate of Pseudomonas aeruginosa from a clinical case of mastitis were all inhibited by the three crude extracts at 820 micrograms concentration. An in vivo trial feeding 1.5 kg of the cooked leaf per day for 5 days did not give a significant cure rate, whereas a second trial in which 0.77 kg of leaf powder, equivalent to 3 kg of wet leaf, was fed per day for 5 days resulted in an apparent cure rate of 92.8% (52.8% actual as there was a 40% spontaneous cure rate in the negative control group, in contrast to 80% (40% actual) in the positive control group treated with an intramammary antibiotic preparation. The difference in cure rate between the negative control group and the experimental group given 0.77 kg leaf powder was significant (p = 0.008).