28 June 2019
Coccidia parasites are hidden productivity thieves
01 November 2018
Coccidia parasites are widespread in NZ, and are often ingested by calves causing intestinal damage, and sometimes resulting in bloody scours. Even when calves are not scouring the coccidia parasite causes significant damage to the lining of the intestinal tract causing calves to lose body condition or limit weight gains.
NZ dairy calf meal feeds should contain a coccidiostat which keeps coccidia under control whilst calves are being fed this meal despite, ingesting some coccidian oocysts whilst grazing. Cocciostats keep cocci numbers low rather than eliminate infection, so calves can be very susceptible to coccidiosis when meal feeding ceases and cocci numbers multiply. In many cases this coincides with other stressors such as trucking calves to a grazing property, and associated feed and social structure change.
It is not uncommon for severe damage to the intestinal tract to be seen even in calves with very low oocyst counts. NZ study demonstrated even when coccidia challenge is low, treatment with toltrazuril results in a weight gain advantage of up to 5kg per calf following weaning which indicates the productivity impact the coccidia parasite has on young calves.
Coccidia parasites can be effectively controlled with a single dose of Toltrox at weaning from meal. This oral drench kills all of the rapidly multiplying, intracellular stages of coccidia resulting in a long-term reduction in oocyte excretion and subsequent environmental challenge. Calves weighing 100kg require a single 30mL dose for coccidiosis control. Local company AgriHealth has recently made Toltrox is available in a 1L backpack, with oral drenching guns so it’s quick to treat the whole mob.
Be particularly alert for signs of faecal staining or blood especially in calves aged one to five months old, and or on farms with historical issues of calves not thriving after weaning from meal. Talk to your vet or look for the Toltrox display at your local clinic.