Valnemulin

A blinded, randomised, placebo-controlled clinical trial was conducted to evaluate the efficacy and safety of valnemulin hydrochloride premix during an outbreak of epizootic rabbit enteropathy (ERE) when administered in feed for 21 consecutive days after confirmation of the first ERE case. Administration of valnemulin at 20 and 35 parts per million (ppm) significantly reduced mortality by 11% and 7.6%, respectively, when compared with the non-medicated control group (23% mortality). Non-ERE related adverse events, including dysbacteriosis, enterotoxaemia and pneumonia, occurred in all groups at similar frequencies (untreated: 1.8%; 20 ppm valnemulin: 2.8%; 35 ppm valnemulin: 1.3%). Administration of valnemulin did not affect feed consumption or body weight gain; treated rabbits had sustained weight gain and feed conversion rates (FCRs). However, from days 7 to 21 of the outbreak, untreated rabbits had significantly lower daily weight gains and higher FCRs than medicated rabbits, suggesting a protective effect of valnemulin during the peak of the disease.

CONTEXT: It is necessary to develop a new salt of valnemulin to replace the veterinary antibiotic, e.g. valnemulin hydrochloride, in order to overcome its instability during storage and preparation.