Q. I HEARD THAT BY USING PARACOX®-5 IN MY FLOCKS, I CAN SAVE MONEY BY REDUCING THE USE OF STARTER AND GROWER FEEDS WHILE INCREASING THE USE OF LESS EXPENSIVE WITHDRAWAL FEED. WHY WOULD THIS WORK FOR PARACOX-5 AND NOT FOR MY REGULAR IN-FEED ANTICOCCIDIAL CONTROL PROGRAM? A. Since their introduction in the 1960s, anticoccidials and growth promotants have largely determined the duration and design of current poultry rations. There have been refinements in rations to reduce overall feed cost and improve feed efficiency, but the basic principles of starter/grower/withdrawal duration and formulation are still based on maximizing the efficacy of the infeed medications. Some of these 40-year-old ration principles have been challenged in the past decade with programs using salinomycin in early feeds paired with a long withdrawal time. Such programs rely on the development of immunity to coccidiosis but, too often, immunity is still developing when high-yield breeds are reaching maximum growth potential. These programs risk a longterm performance loss as field anticoccidial resistance increases. In some cases, full-scale coccidiosis outbreaks have occurred. Regardless of whether a classic starter/grower/withdrawal ration or a 4-week salinomycin/withdrawal program is used, rations must still be formulated to maximize the efficacy of the in-feed anticoccidial. These 40-year-old ration concepts were not designed for the high-yield breeds of the twenty-first century. Paracox-5 stimulates predictable immunity during the early part of the broiler growth curve, before the maximum growth rate occurs. Rations can be formulated more specifically to the physiological needs of today’s highyield breeds. During the first 14 days, rations can be designed to maximize development of the intestine, thyroid and immune system. Birds then “coast” during the immunity-building phase from 14 to 21 days, and the growth curve after immunity is developed can be maximized. These modern-day rations are not restricted by the efficacy requirements of in-feed medications. Q. WHICH TECHNOLOGY DOES SCHERING-PLOUGH RECOMMEND TO HELP ENSURE EFFICIENT, UNIFORM APPLICATION AND SUCCESSFUL COCCIDIOSIS CONTROL? A. The best method of applying Paracox-5 has evolved as knowledge and technology have permitted. Initially, the water application method was used, then the spray-on-feed method, and now, hatchery spray is recommended. The SprayCox II machine with the dual nozzle system for application on chicks has improved vaccination coverage by utilizing a more efficient spray pattern, which increases the amount of vaccine applied directly to the chicks. Delair Bolis, DVM Charles Broussard, DVM Steve Fitz-Coy, PhD Dr. Luciano Gobbi, DVM John McCarty, DVM Linnea Newman, DVM Rick Phillips, DVM John Radu, DVM