Baycox® Stand-Alone Treatment for the Control of Broiler Coccidiosis

The usefulness of the different ways to control broiler coccidiosis is debated intensively. Common coccidiostat in-feed programs are weighed against day-old vaccination with attenuated Eimeria vaccines (precocious lines). In addition, other innovative and reliable control methods are worth investigating. Baycox® stand-alone treatment represents a new alternative to developed coccidiosis control programmes.

The programme is based on the strategic application of Baycox® to the broilers after the natural exposure of the birds to the resident coccidia parasites on the farm. Due to Baycox®'s high therapeutic efficacy, as well as its capability to stimulate the development of immunity against the coccidiosis parasite, the programme enable the broilers to maintain their performance parameters even in the absence of coccidiostat-medicated feed.

It was shown in two floor-pen trials, conducted in a conventional broiler house using the seeder bird technique, that a two-day medication course with toltrazuril during the early stages of Eimeria cycling and recycling controlled coccidiosis (E. acervulina, E. maxima, E. tenella ) very well without clinical relapses or recurrence of oocyst shedding (Mathis et al. , 2003a and 2003b, PDF-File 942 KB). Growth and feed utilisation efficiency was not inferior to classical in-feed coccidiostat programs. It could be shown that targeting such a two-day treatment within a window of 5 days (days 10 – 14) provided optimum results.

The results of these trials were confirmed twice in a clinical setting with commercial broilers exposed to natural coccidiosis infection (predominantly E. acervulina). The toltrazuril stand-alone treatment did not impair coccidiosis immunity and provided an efficacious and cost-effective control of broiler coccidiosis (Gonzalez and Melendez, 2002, PDF-File 820 KB).

Although field and laboratory evidence indicates that resistance to toltrazuril develops rarely and slowly, even under intensive use (Vertommen, H.W. Peek (1993): Anticoccidial efficacy of diclazuril (Clinacox®) in broilers: sensitivity tests; resistance development; cross-resistance in Baycox®. VIth Intern. Coccidiosis Conference, 21 - 25 June 1993, Guelph, Canada), it is recommendable not to deplete the potential of this drug and to implement the programme in one out of 3 to 6 successive grow-outs. In spite of the fact that resistance to diclazuril and toltrazuril only partially overlaps (Haberkorn, A. (1994): Investigations on cross-resistance of coccidia against toltrazuril and diclazuril. 9th Japanes-German Symposium on Protozoan Diseases, 13 - 17 Sept. 1994, Obihiro, Japan.), broiler producers are advised to space both compounds efficiently during successive grow-outs.

Field experience from different countries strengthens the belief of the broiler industry that incorporating the Baycox® stand-alone concept into a rotation program is a valid and economic option. Compared to traditional in-feed prevention and vaccination coccidiosis control programmes, control with the Baycox® stand-alone programme was equivalent or at times even better.

Main considerations of the Baycox® stand-alone programme

• 10 to 14 days is the best window in which to target the medication.
• This programme is useful for the average broiler farm, but maybe not reliable enough for those farms ranking the lowest for coccidiosis management or with very high challenge of the parasite.
• Controlled studies and field experience indicate that use of Baycox® in 2 consecutive grow-outs does not induce field resistance.
• Because of overlapping sensitivity/resistance, rotating Baycox® with diclazuril is not recommended.
• A suggested useful approach is to implement one Baycox® stand-alone grow-out every 3rd or 6th grow-out, grown on other coccidiosis programmes (in-feed and vaccination).
• Without in-feed protection by appropriate performance enhancers or ionophores there are real risks for NE episodes in vaccinated or Baycox® SA flocks. NE infection pressure will build up progressively on broiler farms! Enzyme supplementations e.g. for wheat-based rations need to be optimized. Preventive Competitive Exclusion strategies at 1 day old are useful control assets. In-water therapeutic medications are often unavoidable.

Programmes rotating in-feed coccidiostats, vaccines and Baycox® stand-alone treatment are useful approaches to maintaining the longevity of coccidiostats, vaccines, and Baycox®.