Oral drench

Oral drenches administer a set volume of chemical to the mouth/throat of cattle. This can be done with either a drench gun or a drench hook.

  • Drench guns require cattle to be restrained in a head bail.
  • Drench guns require the operator to stand in front of the bailed animal.
  • Insert the drench gun horizontally into the mouth, and gently but firmly, over the back of the tongue. Take care to avoid damage to the mouth teeth and gums.
  • Take care to avoid directing drench liquid into the trachea.
  • Drench hooks can be used without head bailing on cattle confined in a race.
  • Insert drench hooks into the corner of the mouth where the upper and lower lips meet so that the hook opening comes to rest at the level of the rear molars.
  • Retreat cattle that spit drench out.
  • Check calibration of equipment to ensure the correct dose by applying into a measuring cup or cylinder to check the volume.

Resistance

A parasite population can develop resistance to a chemical through:

  • repeated use of the same active.
  • wide-spread under-dosing of a chemical (e.g. under-estimating the weight of animals being treated, poor application technique, uncalibrated dosing).
  • unintentionally exposing non-target parasites to chemicals (e.g. products to treat tick or lice can also affect worms).

Pour-on applications can be susceptible to under-dosing (see points above) plus caked mud, lesions, wet skin etc can reduce chemical uptake. Social licking may also decrease the actual dosage received.

What is resistance?

Pros

  • Ready to use products.
  • Efficacy is completely independent of weather conditions and animal behaviour following treatment.

Cons

  • Suspensions must be thoroughly shaken before use to ensure accurate dosing.
  • May result in less accurate dosing if animals spit of cough drench.
  • More time handling stock compared to a pour-on product.
  • Animals required to be in a head bail or crush for treatment.
  • Important to administer drench to the correct part of the throat.

Safety

  • Low risk of inadvertent chemical exposure If used according to label directions.

Everyone working in the rural industry has a ‘duty of care’; a legal obligation to provide a safe workplace for everyone on the property.

Additional information

Drench gun

Oral drenching requires use of a purpose manufactured hand piece or drench gun to deliver a set volume of drench to the bovine throat. A drench gun connects by a hose to the drench container or backpack and uses hand compression of a lever to deliver a set volume of drench to each animal.

Drench guns must be calibrated at the beginning of the drenching procedure by setting the required drench volume on the gun cylinder and then measuring over a number of deliveries that the correct volume of drench is being delivered. A calibrated measuring cylinder is used to measure the volume delivered by the drench gun.

Cattle should be restrained in a head bail. The operator stands in front of the bailed bovine and passes the drench gun horizontally into the mouth, and gently but firmly, over the back of the tongue, taking care to avoid damage to the mouth teeth and gums. Care must be taken to avoid directing drench liquid into the trachea. Cattle occasionally spit or cough the drench from their mouths. If this occurs the animal should be partially or completely re-drenched depending on whether the dose was partly swallowed or not at all.

Drench hook

A drench hook is effectively a drench gun extension or a further attachment to the drench gun in the style of an elongated tubular metal hook. This device enables oral delivery of drench to cattle confined in a raceway, without head bailing. The hook is caught into the commissures of the lips of standing cattle. Once in place with the hook opening comes to rest at the level of the rear molars. Hand compression of the drench hook lever rapidly delivers liquid drench to the back of the throat from where it is swallowed.

A drench hook is best used by an operator walking on a raised platform putting him or her at an ergonomically correct height for easy access to the mouths of cattle in the raceway. Use of a hook removes the need to head bail each animal.