Faecal egg counts in cattle: how do they stack up?

Faecal egg counts (FECs) are commonly promulgated as a means of determining the status and impact of parasitic gastroenteritis (PGE) in cattle, yet there is little scientific evidence for consistent, quantitative associations between FECs, worm burdens or the effects of PGE on the hosts. Examples are provided of applications of FEC in cattle that do have an evidence base and also of alternative aids to anthelmintic treatment decisions, such as growth rates in young cattle. The potential value of FECs in veterinary/farmer interactions is also addressed as is the need to justify diagnostics through demonstration of favourable cost–benefit ratios