Effects of Nuxasan 500™ on Broiler Performance and Intestinal Health

Effects of NUXASAN 500™ on the performance and intestinal health of broilers challenged with Eimeria spp. 

Coccidiosis, a disease caused by species of the genus Eimeria, is one of the most economically devastating diseases in the poultry industry. The result of infection caused by this parasite can lead to variable clinical signs, from subclinical diarrhea to more serious cases with increased mortality. The low weight gain and poor feed conversion generated by this condition cause significant economic losses in a combination of direct and indirect costs: 

1. Direct costs: 

• Treatment and Prevention: The cost of anticoccidial drugs and vaccines used to prevent and treat coccidiosis can be substantial. This includes both the cost of the products and the labour required to administer them. 
• Veterinary services: Expenses related to veterinary services for diagnosis and management of coccidiosis outbreaks contribute to the overall cost increase. 

2. Indirect costs: 

• Low performance: Infected birds generally show a decrease, not always noticeable, in performance, leading to lower overall productivity. 

• Mortality: Severe cases of coccidiosis can lead to high mortality rates, resulting in direct losses in the poultry herd. 

• Decreased egg production: In layers, coccidiosis can cause a significant drop in egg production and quality, affecting profitability. 

3. Long-term economic impact: 

• Development of resistance: The development of resistance to anticoccidial drugs creates the need for continuous development of new solutions and protocols, leading to a slow and costly process. 

• Research and Development: Significant investments are made in research to develop better management practices, vaccines and alternative treatments. 

Traditionally, the prevention and control of coccidiosis has been based on chemoprophylaxis, anticoccidial products (coccidiostats and coccidicides) and the vaccination of birds with selected Eimeria oocysts. However, there are several concerns associated with their use: 

1. Drug resistance: 

• Development of resistance: The continuous and widespread use of anticoccidials has led to the emergence of drug-resistant coccidial strains. This resistance reduces the effectiveness of existing treatments and makes it difficult to manage the disease. 
• Management strategies: To combat resistance, strategies such as the rotation of different classes of anticoccidials, the use of combination therapies and the integration of non-chemical control measures are recommended. 

2. Residues in Food Products: 

• Risks to human health: Residual traces of anticoccidials in meat, eggs and other products of animal origin can pose risks to consumer health; safety intervals are needed to avoid this risk. 
• Regulatory standards: Regulatory agencies establish maximum residue limits (MRLs) for anticoccidials in food products. Ensuring compliance with these standards is crucial for food safety. 

3. Environmental Impact: 

• Contamination: Anticoccidials can enter the environment through animal waste, contaminating soil and water. This can affect non-target organisms and contribute to the wider issue of antimicrobial resistance. 

• Cross-contamination: To avoid cross-contamination of food with different anticoccidials, it is very important to properly clean and disinfect the facilities. 

• Mitigation measures: Proper waste management and treatment practices are essential to minimise environmental contamination. 

4. Animal Welfare: 

• Excessive and improper use: Over-reliance on anticoccidials can lead to poor health outcomes, accelerated development of resistance and reduced animal welfare.  

• Alternative Approaches: Incorporating alternative non-chemical approaches, such as polyherbal products, can support animal performance and health, as well as reducing dependence on and resistance to traditional anticoccidials. 

5. Regulatory compliance and monitoring: 

• Ensuring compliance: Effective monitoring and enforcement of regulations regarding the use of anticoccidials is crucial. This includes compliance with safety intervals before slaughtering animals or marketing their products. 

• Global Standards: Harmonising global standards and practices can help mitigate the risks associated with international trade and guarantee consistent food safety and animal health practices. 

To address these concerns, a multi-faceted approach involving regulatory oversight, industry practices and scientific research is needed to ensure safe and cost-effective strategies to control avian coccidiosis while protecting public health, animal welfare and the environment.  

In response to growing concerns about the use of drugs, synthetic additives and resistance in poultry production, there is increasing interest in natural phytogenic supplements, which aligns with the growing demand for organic animal products in the global market. 

In this context, a study was carried out at the University of Georgia, USA, to investigate the effects of NUXASAN 500™ (Nuproxa Switzerland, Ltd.), a product of natural origin, as an alternative strategy to synthetic anticoccidials.  The work evaluated its effect on performance, intestinal integrity, oocyst count, expression of pro-inflammatory cytokines and on the antioxidant system at the level of the intestinal mucosa in broilers experimentally challenged with Eimeria spp.

A total of 288 one-day-old male Cobb 500 broilers were randomly assigned to 3 treatments with 8 replicates per treatment and 12 birds per cage for 28 days. The treatments were: Negative Control, NC (basal diet, not challenged), Challenge Control, CC (basal diet challenged with Eimeria spp.) and CC + 500 ppm NUXASAN 500™ (NUX). Birds in the CC and NUX groups were orally inoculated with 62,500 oocysts of E. acervulina, 12,500 oocysts of E. maxima and 12,500 oocysts of E. tenella on day 14, and the NC group was orally inoculated with the same amount of PBS. 

Table 1. Performance results at 28 days. 

NC, Negative Control; CC, Challenge Control; SEM, standard error of the mean.

Table 1 shows the performance results at 28 days, where the birds in the NUXASAN 500™ group were significantly heavier, with lower FCR and mortality.

As shown in Figure 1, the use of NuxaSan 500™ achieved a significant reduction in the excretion of oocysts (P<0.05) of E. tenella at 6-7-8-9 days post-inoculation (DPI), E. maxima at 7 and 9 DPI and E. acervulina at 6 DPI (P=0.055). 

Figure 1. Oocyst sheding counts in feces of broilers challenged with Eimeria spp. CC, Challenge Control; NUX, NUXASAN 500™. *shows significant differences at p<0.05.

The CC group also had numerically the highest incidence of severe lesions and an average score of high lesions in the duodenum, jejunum and caecum. NuxaSan 500™ mitigated the incidence of severe and very severe lesions in the duodenum and caecum caused by Eimeria spp. 

Figure 2. Effect of treatments on intestinal lesion score at 6 DPI in broilers challenged with Eimeria spp. (from 0 = no macroscopic lesion to 4 = very severe lesion, numerous blood clots, characteristic colour and odour). “a-c” different letters between columns shows statistical differences p<0.05.

In gene expression analyses, challenge with Eimeria spp. increased (P<0.05) the gene expression of claudin 1 (CLDN-1) and pro-inflammatory cytokines – interleukins IL-1β, IL-6, TNF-α and IFN-γ in the jejunum compared to the NC group; in contrast, in NUXASAN 500™ group, the gene expression of CLDN-1 and IL-1β, TNF-α in jejunum was reduced (P<0.0001) and the expression of the enzyme glutathione peroxidase (GPx) in the jejunum was numerically increased compared to the CC group.

The economic impact of coccidiosis in poultry is significant, affecting both large-scale commercial operations and small-scale producers. Effective management strategies, including good biosecurity practices and the development of alternative treatments, are essential to mitigate these costs and ensure the sustainability and profitability of the poultry industry. 

Supplementation with 500 ppm NUXASAN 500™ effectively mitigated the negative effects caused by the challenge with Eimeria spp., proving to be an efficient nutritional strategy for improving the performance and intestinal health of broilers challenged with coccidiosis, as well as improving the profitability of the system as a whole.