Spring advice for small block farmers
September 2022

Tail docking lambs

Lambs’ tails are docked to reduce their risk of flystrike. A long tail allows for dags which attract the flies increasing the risk and severity of flystrike in the summer.

Lambs’ tails can be docked up to 6 months of age and must be done with a rubber ring or hot iron. After 6 months it must be done surgically by a veterinarian.

The tail must be long enough to cover the vulva (and similar length in males). This protects the vulva from sun damage. While we want the tails shorter to prevent flystrike, tails too short can also increase risk of flystrike and can also cause uterine prolapses after lambing.

Lambs should get their clostridial vaccinations before tail docking to ensure they are protected from tetanus.


The animal welfare regulations allow rubber ring castration in sheep, goats, and cattle until 6 months of age. After this time, it is required to be surgically done by a veterinarian.

Often the testes will be too big to be rubber ringed successfully before they reach 6 month of age and should instead be done surgically by a veterinarian. It is a lot easier for us to surgically castrate than to fix a rubber ring job that has gone wrong. When using a rubber ring you
need to ensure both testes are below the ring and make sure none of the teats are included (yes, like humans the males have nipples too).

Horses and pigs must be castrated by a veterinarian with the necessary pain relief given.

If you are unsure about any castrations or tail docking we can do this from any age. These are painful procedures, and it is better to be done right.

Disbudding and dehorning is a painful procedure; it is not like cutting the fingernails. There is a good nerve supply to the horn. The Animal Welfare Regulation now states that disbudding and dehorning must be done “under the influence of pain relief that is authorised by a veterinarian for the purpose of the procedure”.

For calves we recommend disbudding from 2 weeks of age. For goat kids they need to be under 10 days to be disbudded.

Poisonous plants

Many commonly grown plants around lifestyle blocks can pose a risk to stock with potentially fatal outcomes. Even as little as two leaves from some of these plants can be fatal to livestock. Although often unpalatable, animals that are very hungry, bored, or even slightly curious may decide to try them – it is in these circumstances we need to be extra vigilant in keeping the animals away from these plants.

Left to right: Avocado, Agapanthus, Rhododendron.

Some of the most common plants that can cause toxicity:

  • Arum lily
  • Agapanthus
  • Avocado trees
  • Black nightshade
  • Buttercup
  • Karaka berries
  • Hemlock
  • Goats Rue
  • Macrocarpa
  • Foxglove
  • Rhododendron
  • St Johns wort
  • Oleander
  • Oak / acorn trees

Clinical signs of toxicity:

  • Vomiting + diarrhoea
  • Circling + abnormal gait
  • Abdominal pain
  • Weakness + lethargy
  • Excessive drooling
  • Collapse/coma
  • Bloat
  • Sudden death
  • Rapid breathing

Animals may show one or many of these signs.

Prevention is key – ensure livestock have:

Sufficient feed – avoid animals having the urge to gorge on the plant material

Adequate fencing around plants ensuring there is enough room between the plants and the fence so the animals cannot stick their heads through to get it

Clippings of the plants are disposed of correctly and not fed to your animals

Check your paddocks after a storm – branches may end up in the paddock with the animals

If you are worried your animal has ingested a toxic plant, make sure you remove them from it immediately. Give them access to fresh clean water and call your vet as soon as you can.


Worms that cause disease in lambs and calves can be controlled by drenches. A lamb should ideally get its first drench at weaning time, approximately 3–4 months of age. Calves should be drenched 3–4 weeks after they are weaned off milk or milk replacer. After the first drench, youngstock should be drenched according to faecal egg counts, or every 4 weeks until the following April/May. After that, lambs and calves develop immunity and have a reduced requirement for drenching.

Drench for lambs and calves is usually given orally. Once calves are over 100kg however, there are also a pour on or injectable drench options. Because the amount of drench needed is based on weight, it’s important to have a rough idea about how much the animal weighs. Drench actives can be toxic to other species so care should be taken that it is only given to the animals it is intended for.

Other animal species, including pigs, chickens and goats will also need to be drenched routinely throughout the year. Pop into your local clinic to get advice on which products to use and when to apply the drench.