Pasture is a hunting ground for parasites, albeit on a microscopic level. Though many worms cannot be easily seen with the naked eye, their effects on stock can be, ranging from reduced growth rates to death.
Common signs of parasitism:
- Diarrhoea/dags
- Weight loss
- Potbellied appearance
- Lethargy
- Decreased appetite
- Bottle jaw
Internal parasites are shed in the faeces. Stock become infected when they graze the pasture. Young and immunocompromised animals are the most severely affected and shed the most parasites. As sheep and cattle get older, their immune system matures, and they are less affected by worms. Alpacas and especially goats do not develop a robust immunity to worms with age.
Effectively managing worms requires a multipronged approach. Below are some handy tips:
- Cross graze with other stock e.g. sheep with cattle – worms are often species specific.
- Graze young stock ahead of old stock.
- Pasture management – the most effective way to prevent worms! Ensure grass is long. Most worms are found in the bottom 5cm of grass. Grazing pasture >5 cm means less exposure to worms. Feeding supplement can help take the pressure off the pasture.
- Regularly drench at risk stock e.g. young stock once they are out on pasture, until autumn. Note: there is some drench resistance developing, so it cannot be solely relied upon. If in doubt – bring in a faecal sample and we can check it to see if worms are present. Oral drenches are best. Any new stock coming in should have a quarantine drench.
If you have any questions or want a sounding board, just call the clinic – we are always happy to help!
