Merial introduces Zactran, an antimicrobial for the treatment of bovine respiratory disease in dairy heifers from birth to 20 months.
Zactran, the first macrolide introduced to the market since 2005, takes just 30 minutes from the time subcutaneous injection to reach therapeutic levels in the lungs, says Tom Van Dyk, a veterinarian with Merial. And it remains at that level for 10 days, making it ideal for both treatment and control of Mannheimia haemolytica, Pasteurella multocida and Histophilus somni in non-lactating dairy cattle and beef.
Zactran has a 35-day meat withdrawal requirement. Because a discard time has not been established for milk, the product should not be used in lactating cattle.
Dosages vary by body weight. For example, a 110-lb. calf requires just 2 mL of product while a 550-lb. heifer requires 10 mL. No more than 10 mL should be administered per injection site.
The product comes packaged in two sizes: a 250 mL bottle containing enough solution for 62 head of 220-lb. cattle and a 100 mL bottle containing enough solution for 25 head of 220-lb. cattle. The bottles come encased in a plastic protector which makes breakage unlikely, even if dropped on concrete floors. The bottle/protector combination can be hung upside down for continuous use chute side. Labeling is configured so that treatment directions can be read right side up even when the bottle is hung upside down.