Blood-sucking worm
Barber's pole is a worm named for its red and white striped appearance. The red is the blood it has sucked from your animals. Significant burdens can cause significant reductions in productivity. Know your enemy.
Barber's Pole (Haemonchus contortus) sucks blood from the abomasum (the fourth stomach), causing anaemia and death in animals. It's usually lambs that suffer but severe burdens can also affect ewes. Outbreaks are seen in summer and autumn with rain or heavy dews during or after a hot dry spell.
It is not unusual for burdens to be high enough to cause anaemia in animals. The range of signs seen in affected animals varies:
- Ill-thrift (may be seen as a large tail-end)
- Pale gums
- Rapid, shallow breathing
- Animals lagging at the end of the mob
- Collapsed or dead animals
It is not typical for barber's pole to cause a scour as it sucks blood, so works in a different way to other parasites.
Now is a critical time to be monitoring for barber's pole. It is also essential that you know how you are going to treat if this disease occurs. Many drenches have a claim to kill Haemonchus but will only eliminate the current infection. These worms are continually picked up from the environment, so it is recommended to treat with a product that has extended protection against Haemonchus.
Historically, diagnosis has been made by faecal egg counts and larval culture or at post mortem where the large worms can be seen in the abomasum. These methods can still be used but we have a new and exciting test available, the Haemonchus dipstick test.
The dipstick test involves a process of diluting the faeces and heating for a time then measuring the amount of blood in the sample. The blood is released from the lining of the stomach when the worm has had its fill. Obviously, the blood level in the faeces will be higher if the parasite burden is more severe. From this test we can estimate the burden in the animals and make recommendations on further monitoring or treatment.
To monitor we suggest bringing in some fresh faecal samples from your lambs (they can be refrigerated if you cannot bring them in directly). Hold the lambs in the corner of a paddock for five to ten minutes, and then collect ten fresh samples. It is important that they are not collected from the rectum as this method may damage the rectum and cause blood in the faeces. These samples should be kept separate (use an egg carton, or sample packs are available from the clinic).
We can perform a faecal egg count on each sample to determine if other parasites are affecting your animals and if you wish, can go ahead and do the dipstick test to work out if barber's pole is an issue you need to address. When dropping off the sample, it is helpful to know the age of the animals, the date of the last drench and what was used. You will be called with the results and recommendations for further monitoring or treatment.
Treatment and prevention is based on strategic drenching at this time of year. The drug of choice is moxidectin (Vetdectin or Cydectin - 10 day meat withholding period) or abamectin + closantel (Genesis Ultra - 56 day meat withholding period). This should be followed up in 4 to 5 weeks by a second drench in the case of an outbreak.
Know your enemy - monitor and treat accordingly so you do not suffer poor growth rates or lose lambs to this vampire-like parasite.
