Significant improvement in Intestinal Integrity for UK broiler flocks in the first half of 2024

The latest data from Elanco’s Health Tracking System (HTSi) suggests that the Intestinal Integrity (I2) of UK broilers has improved in the period from January to June 2024.

The I2 scores for the first half of 2024 were markedly higher than those of the same period in 2023 and peaked at 96.12 in April, the highest monthly average in over two years. 

Louise Ashworth, Elanco’s strategic account manager and HTSi Lead, is optimistic about these findings: “The first half of the year has been very encouraging. We ended 2023 with high levels of Intestinal Integrity, and this momentum has carried into 2024, with stable and improved I2 values despite challenging weather conditions.” 

Explaining the latest results in terms of the Eimeria challenge, Ms Ashworth says E. acervulina levels, which can have a significant bearing on I2, have continued to reduce.

Louise Ashworth on farm

E. acervulina lesions peaked at 25 days of age at a level similar to 2023, before a sharp decline. We’ve seen a smaller secondary peak than we did last year, which was reduced in severity and observed later, showing at 39 days this year, compared to 30 days in 2023,” she says.

“This later peak may have been due to an increase in slower growing breeds in the data set and suggests that although we’re looking at more birds in later life, E. acervulina is generally being stable and well-controlled.”

Commenting on the other significant species of coccidia, Ms Ashworth notes a slight increase in E. maxima and E. tenella.

“E. maxima has remained higher than expected since May 2022 and has steadily increased in the first six months of this year, following a similar trend to those noted in 2023, and 2022,” she says.

Broilers standing up and laying down

“Average scores of E. tenella have also increased for the first four months of the year, peaking higher than during the same time the previous year, before dropping in June back to the same levels seen in June 2022.”

Ms Ashworth points out that while E. tenella can be associated with bird mortality, 92 percent of the cases seen were mild (score1), with the uptake likely due to an increase in older birds within the data set.

She says it is not a major cause for concern at the moment, but is a reminder that we need to be considering all coccidia species and maintaining robust biosecurity and stable control programmes throughout.


“Producers need to focus on the period between thin and cull; birds can eat a lot during this time and I2 needs to be maintained to maximise efficiency and performance,” says Ms Ashworth.

She adds that although lower bird stocking densities are now being implemented, which in theory should reduce disease pressure, the overall threat of coccidiosis persists.

“Producers must avoid cutting turnaround times to try and make up for the shortfall in production, robust coccidiosis control and hygiene programmes should be maintained.”

Eradicating coccidiosis through cleaning and disinfection alone is not possible and Ms Ashworth stresses the importance of a robust and stable anticoccidial programme in maintaining I2 and maximising bird performance.

“As we head into late summer and autumn, we typically see the greatest challenge to I2 so it’s important to keep everything consistent during this time and don’t let biosecurity lapse,” she says.

While the data is representative of 90 percent of UK broiler units, individual customer and regional variation do exist. Please contact the Elanco team for a more detailed discussion on measuring I2 in your flock.

Use medicines responsibly www.noah.co.uk/responsible. Elanco UK AH Limited, Form 2, Bartley Way, Bartley Wood Business Park, Hook RG27 9XA. Telephone: 01256 353131. Email: elancouk@elanco.com 

Elanco Health Tracking System (HTSi), Elanco and the diagonal bar logo are trademarks of Elanco or its affiliates. © 2024 Elanco or its affiliates. Date of preparation: 07/2024.