Animal Safety

Extensive safety studies in cattle and laboratory animals have demonstrated that Enrofloxacin offers a wide margin of safety.

After oral administration in doses up to 100 mg/kg b.w. in rats, Baytril had no significant effect on blood composition, blood coagulation, diuresis or the central nervous system.

In specific trials it was also shown that Enrofloxacin does not elicit any allergic or pseudo-allergic reactions.

The acute toxicity is very low. The LD50 values were determined in a variety of species.

Different safety studies in cattle and weaned calves demonstrated a wide margin of safety:

Example 1: Dose rates of 5, 15 and 25 mg Enrofloxacin/kg bw were administered daily for 15 consecutive days to Holstein calves (23 days of age). At all dose rates clinical signs, appetite and hematological parameters remained normal. In addition, histological and gross necropsy analysis of soft tissues and articular cartilage revealed no abnormal findings (n=24).

Example 2: Oral administration of enrofloxacin to three-day-old calves at doses of 5, 15 and 25 mg/kg bw for nine consecutive days resulted in no abnormal findings in feed intake or hematological and blood chemistry parameters. No histological abnormalities were seen in kidney tissues and articular cartilage (n=12).

Example 3: Oral administration of enrofloxacin to 14-day-old calves at dose rates of 15 mg/kg bw for 15 consecutive days and 30 mg/kg for seven consecutive days resulted in no adverse clinical signs (n=12)

Example 4: Intravenous injection of 5 mg Enrofloxacin/kg bw via Baytril® 10% injectable solution on three consecutive days to heifers showed no reactions at the injection site and no adverse systemic effects (n=23).

Additional studies with beef calves (60 – 110 kg) demonstrated the safety of s.c. administered Baytril® Max at labeled dose rates. Only when excessive doses were administered for prolonged periods, were adverse clinical signs observed. At dose rates of 15 mg/kg and 25 mg/kg b.w. over 15 consecutive days, some calves showed occasional muscle tremors, gait abnormalities or lethargy (n=16).

The injectable formulations show good local tolerance. Pain at the time of injection was not observed in the test animals. Mild to moderate swelling can occur, depending on the doses administered.

Baytril was also tested in reproductive studies in cows as well as in laboratory animals. No adverse effects on reproduction or fetal development were observed.