ELANCO’S latest gut health tracking report has found higher coccidiosis prevalence than expected.

The firm’s latest mid-year report for the UK has found overall intestinal health in flocks across the UK is improving, but coccidiosis prevalence is still higher than 2021 records.

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The interim report collates intestinal health data from January to July this year from 3,137 post-mortem bird examinations, from 412 broiler houses on 175 UK farms.

Elanco takes this data and produces the I² index, a weighted index that gives flocks a score of between 0 and 100 based on 23 health conditions that negatively impact intestinal health.

For many farms, a score of 90 or below is an indication that poor intestinal health is having a significant impact on FCR and bird performance. Poorer I² scores are linked to a rise in antibiotic usage and an increase in feed, water and space required per kilo of poultry meat produced.


Explaining the latest findings, Louise Ashworth, Elanco’s HTSi lead, said: “In 2022, there was a steady decline in I², which was particularly apparent over the summer, in contrast to previous years.

“Producers often consider the summer to be a ‘safe’ time to make changes to their anticoccidial programme or loosen biosecurity protocols.

“Whereas, over the winter, everyone tends to ‘buckle up’ when it comes to disease prevention,” she said.

Despite this, the I² data is looking far more stable in 2023, tracking similar to that of 2021.


“The average coccidiosis prevalence for July 2023 is lower than what was seen in 2022, for the three common strains seen, which has helped drive an increase in I²,” she says.

“However, it’s important to note that while an initial reduction in both E. maxima and E. tenella has been seen, the prevalence of these strains hasn’t returned to the levels noted in winter and spring of 2021/22 and is still higher than we’d like to see.”

Ms Ashworth added that these results indicate that once intestinal stability has been disrupted, it takes several crops to return.

Long-term impact

The report data highlights that last year’s disease levels were particularly high, and although is on the rise this year, coccidiosis levels are taking some time to reduce back to pre-2022 levels.

“It’s important to be aware that an increased coccidial population can have long-term impacts.

“If a coccidial challenge becomes out of control, it will take multiple crops to return to a manageable level, and producers will need to undertake additional cleanout and disinfection protocols to achieve good coccidial population control in the winter months,” added Ms Ashworth.