Comparison of Monensin / Nicarbazin (Monimax®) with Semduramicin / Nicarbazin

The birds in the trial group got a challenge using Eimeria species which were purified from samples collected in the field. As semduramicin / nicarbazin is not registered in Europe or the US, the samples originated from Asia (Malaysia), Africa (South Africa) and Latin America (Brazil) to ensure the collected Eimeria species were historically exposed to both products.

Materials and methods

In order to compare the two combination products, three different trials were conducted in the same research facility. The protocol of the trials was similar and standardized (Figure 1). 

Figure 1. Standardized protocol of the anticoccidial sensitivity trials (ASTs)

In every trial, the products were evaluated against each other and compared with two control groups; the infected, untreated control group (IUC) and the uninfected, untreated control group (UUC). These control groups are needed to evaluate the severeness of the challenge and to verify that the challenge was done correctly. 

Results

Malaysian (Asian) samples

In the first trial, the sensitivity of the Malaysian Eimeria strains was tested for the ionophores separately (monensin versus semduramicin) and for each of these ionophores in combination with nicarbazin. The different groups were semduramicin (20 ppm and Coxidin® (monensin, 100 ppm), Monimax® (monensin / nicarbazin; 40/40 ppm) and semduramicin / nicarbazin (15/40 ppm). The samples were collected from commercial broiler farms in Malaysia and the composition of the inoculum is indicated in Table 1. As confirmed with qPCR, the inoculum contained all the relevant broiler species by E. acervulina was the most prevalent.

Table 1. Composition of inoculum from Asia

When evaluating the coccidiosis lesion scoring results of the different groups, the birds that received Monimax® were the only group with a significantly lower lesion score compared with the IUC. The separate ionophores did not result in any reduction in the lesions and the combination of semduramicin and nicarbazin only gave a numerical improvement versus the IUC (Figure 2). In correspondence with the lower scoring results, the Monimax® group was also the only treatment with a signficantly higher daily weight gain (DWG) in comparison with the IUC. The benefit of adding nicarbazin to monensin was higher compared with the benefit of adding nicarbazin to semduramicin (Figure 3). 

Figure 2. Lesion scoring results of different treatment groups using the Asian inoculum

Figure 3. Performance results (daily weight gain (DWG) and feed conversion ratio (FCR)) for the different treatment groups infected with Asian Eimeria strains

Brazilian (Latin American) results

For the second trial, the samples were collected from commercial farms in Brazil with a historical use of different combination products. The inoculum proved to be a mixed sample containing all the relevant broiler species with E. acervulina also being the most predominant (Table 2). 

Table 2. Composition of inoculum from Brazil

In this trial, the different combination products (at the lowest registered dose) were compared with each other considering parasitology using performance variables. The lesion scores of the different treatment groups were not significantly different, but Monimax® proved to be the product of choice as it had the highest DWG and lowest feed conversion ratio (FCR) compared with the other combination products (Figure 4). 

Figure 4. Performance results (DWG and FCR) of different combination products using a Brazilian inoculum

South African samples

For the third trial, faecal samples were collected from commercial farms in South Africa with a historical use of different combination products. The inoculum proved to be a mixture of E. tenella and E. maxima (Table 3). 

Table 3. Composition of inoculum from South Africa

Both combination products were used at the lowest registered dose. The lesion scoring results were not significantly different for both combination products. When evaluating the performance, the Monimax® treatment group was the only group with significantly better results compared to the IUC (DWG was significantly better compared to the IUC, Figure 5). 

Figure 5. Performance results of both combination products infected by South African Eimeria strains

Conclusion

In different trials, the efficacy of Monimax® was compared with the efficacy of semduramicin / nicarbazin. Overall, regardless of the geographical origin of the Eimeria strains provoking the coccidiosis infection, Monimax® resulted in better coccidiosis control compared to semduramicin / nicarbazin.