Reducing the Risk of Coccidiosis

Lambs and calves become infected with coccidia by eating/drinking/sucking/licking food, water or objects that are contaminated with coccidial oocysts (eggs).   These are passed in dung and in damp conditions are able to survive in the environment from one year to the next.  Coccidia are quite fussy – the species of coccidia that infect lambs will not infect calves and vice versa.  Disease outbreaks occur when the numbers of coccidial oocysts in the environment reach high levels and control is based on reducing exposure to these.  A balance has to be struck as exposure to small numbers of oocysts is needed in order for lambs and calves to develop immunity to them.

• When buildings are empty either steam clean or use disinfectants capable of killing coccidial oocysts. (e.g. Kilcox Extra, Kilco Ltd.).
• Compost bedding/manure before spreading.
• Don’t over stock buildings or fields.
• Avoid stocking lambs/calves in pens/fields already used by earlier born lambs/calves.
• Remove scouring lambs/calves from the group.
• A good intake of colostrum will help protect lambs/calves against all bugs that cause scour.
• Clipping tails or dagging will help keep teats and udders clean.
• Use plenty of clean dry bedding, fix leaking troughs/gutters and make sure drainage is adequate.
• Regularly change the position of shelters and troughs in fields.
• Site water and feed troughs to reduce the chances of animals dunging in them.
• Avoid grazing young animals on fields where there was a problem the previous year.

In some systems, particularly where lambs/calves are housed for long periods, the risk of coccidiosis can be high and medication is needed in order to avoid problems.  Decoquinate (Deccox) can be added to creep feed and needs a veterinary prescription.  Protection against coccidiosis relies on lambs/calves eating sufficient concentrates.  Look out for disease outbreaks once medication is withdrawn.  Otherwise preventive treatment can be targeted by dosing with Diclazuril, (Vecoxan), or Toltrazuril, (Baycox, Cevazuril).  Consider when problems with coccidiosis have occurred in previous years and use these products just before this time.  Scour due to coccidiosis is diagnosed most commonly when lambs and calves are aged between 4 and 8 weeks.

Heather Stevenson, Veterinary Investigation Officer, SAC Consulting