Internal and external parasites in youngstock can have a massive effect on the weight gain and health of these animals. Knowing when to drench and what to drench with can be difficult, as there are multiple factors that have an influence. 
 
Age of the stock, stocking rate, other species being grazed on the pasture, and environmental conditions to name a few. As a general recommendation, youngstock should be drenched with at least a double active drench every 28 days from weaning though to late autumn/winter however, the drenching interval can change significantly depending on the parasite burden in the environment. With current dry conditions, the eggs that are passed out onto the pasture will remain dormant, as they require moisture to become infectious. The dry conditions do not kill the eggs however, so when the rain does arrive, there will be a large number of parasites developing into the infectious stage in a very short period of time, so particular care with drenching intervals will be required at this point. 
 
Every farm is unique, and a one size fits all approach to parasite management will not provide the best management or performance for many farms. One easy way to help make appropriate management decisions around parasite management is to find out if your youngstock does have parasites. Performing faecal egg counts will help give an indication of the possible worm burden present in your animals and can help indicate when drenching is appropriate. 
 
Making a drench plan through discussion with your veterinarian will help you manage the parasites in your stock in the most efficient way, allowing you to get the best performance, while potentially saving money on drench.