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Video 31 Six areas to focus on for lamb performance at pasture


I have said before that with beef and sheep we are in the business of weight gain. We must do this while being mindful of any inputs.

We need to maximize our lambing % and then make sure we can get the maximum number of lambs for sale. We also need to set a target for DLWG and then make sure nothing upsets this to hit optimal growth.

I’m going to cover six key areas for lambs to optimize their health during the grazing period.

The building blocks for lamb performance are milky ewes and available feed to match the growth rate. This means that we need to maximize DMIs in young lambs particularly after weaning time.

  1. Nemadtodirus Battus

One of the first challenges for lambs is the roundworm nemadtodirus. It is a parasite that can affect flocks in late spring/early summer. This worm is unusual because the parasite develops in the egg. When the weather conditions are right then we can have mass hatching of this infective larvae (immature worms).

The conditions required for this are temperatures of over 10 degrees for a week or more. For most parts of the country right now in late April, we have seen the risk of nemadtodirus is quite high. It can affect lambs between 6-12 weeks.

It is a parasite that we need to act differently too. Fecal egg counts can be of limited value because of mass hatching. By the time we see eggs in the dung a lot of clinical setbacks may have occurred.

We typically manage this parasite by knowing if there is a risk and then monitoring clinical signs. The signs of this parasite are dirty back ends (tails) with a brown watery scour.

Of course, we should never make presumptions especially with coccidiosis being a differential as well.

Thankfully there is no resistance to nemadtodirus in our flocks. Meaning a benzimidazole (white) drench will work very well.

So at the present where this is a risk, a white worm dose timed well works well. Lambs will subsequently develop resistance. We also must be mindful of grazing lambs on the same pasture every year.

So if your flock is known to be at risk with our current weather conditions its time for vigilance and probably be prepared to take action.

  1. Coccidiosis

While many sheep farmers are aware of the symptoms of coccidiosis. Typically we can see black bloody scours and straining. However, we must be mindful also that when we don’t see symptoms we can still see issues with coccidiosis affecting performance.

This means that live weight gain becomes a very important tool for monitoring the lamb performance.

We can treat lambs to cover them for coccidiosis again by a well-timed therapeutic or prophylactic dose of an anti-coccidial product.

Minimize the risk at pasture by moving creep feeders and avoid mucky areas around water drinkers.

React fast to dirty tails and poor performance. Try and get dung samples to make a diagnosis of what might be happening to these lambs

  1. Vaccinate against infectious disease

The big bacterial disease which is a risk at pasture are clostridial diseases. The common ones for lambs are blackleg, chavuoei, pulpy kidney disease, etc.

With a very effective 10&1 vaccine for clostridial disease in lambs, I think this is a must.

Be mindful this vaccine needs two shots 3-4 weeks apart. One-shot will give very poor and short cover.

If pneumonia is an issue in lambs then farms should consider Pasteurella vaccination in their flocks. Typically it can be younger and older lambs that we see issues.

Watch the video above as I discuss lamb performance

  1. Scald

Very often mid grazing season a condition that rears its head is scald. This is a bacterial infection that affects the feet. It causes reddening and swelling with some lambs becoming very lame. The risks for scald are in wet pastures during the summer months.

The good news in lambs is that they respond very well to footbathing once a diagnosis is made. The key thing with lambs is to get them to spend time in the footbath. Most of your footbaths biocides are very effective against scald.

The challenge can be that getting lambs in for footbathing can be difficult. This is where good handling facilities are a great long term investment.

Farms that’s have had issues with scald should consider regular footbathing lambs whenever they are being handled, weighed or using routine treatments.


  1. Worms

This is a big issue that affects lamb performance at grazing. This has become more complicated in flocks where worm resistance is now a real problem.

Worm resistance is where the dose we use is becoming ineffectual against the parasite. This level of resistance can vary between farms and dosing products.

With high levels of resistance to white doses and clear (Ivermectin) drenches. We also have resistance against the yellow (levamisoles). We also have two new products on the market orange and purple drenches.

These new products are now our opportunity to be smart around dosing and keep these working for as long as we can.

Any farmer who now looks at worm control with products only will find it increasingly harder to finish lambs.

We need to have a parasite control program for young lambs.

Early on we must start monitoring weights, clinical signs and using FECs to monitor parasite levels in dungs.

Fecal egg counts, in my opinion, have a role to play in young lambs. We could get more value by using pooled samples every 3 weeks from about 6 weeks.

This will seem like an excessive approach but with the rising levels of resistance, I feel this is where top producers will be in the coming years.

As the season progresses we can rely less on FECs and must monitor weights and clinical signs.

We need to look at grazing strategies also. I am very excited about the potential of mixed species swards in sheep systems. They have many benefits but the early work would suggest they have benefits for parasite control also.

The main factors seem to be the physical difficulty larvae have with these swards (getting into lambs) and they also appear to have natural products like tannins which may have anti-parasitic properties.

We will still need dosing but must be mindful to rotate between years and also look at utilizing the orange and purple drenches only when needed.

Farms not struggling with resistance please focus heavily on good quarantine doses


  1. Minerals

The last area to manage in lamb performance is minerals. The big one for me is cobalt and Vit B12 which all lambs need to be supplemented within grazing systems. Lambs are more prone to issues with these two because of the need for B12 in wool growth. All young growing ruminants require Cobalt (B12) but this is very important in young growing lambs.

Cobalt itself is required to be converted into B12 in the rumen. This plays a vital role in energy metabolism in young lambs.

We can blood test our lambs to measure cobalt (B12) or like most farmers, we will need to supplement lambs particularly when they start growing.

The other minerals for lamb thrive are selenium, copper, and iodine from my experience. Now we must be very careful when supplementing both selenium and copper in lambs as we don’t want to over supplement and cause toxicity.

One idea for sheep farmers when it comes to managing lambs and trace elements is to look at soil and grass analysis. This helps us decide what our deficiencies on-farm are.

Most sheep farmers will use regular mineral supplementation especially after weaning. Some flocks may also see trace element issues in younger lambs with ewes with mineral deficiencies.

So the plan should be building a mineral profile for your flock. Then supplement when needed. I think most flocks benefit from routine cobalt B12 supplementation around or after weaning.



These for me are key areas to focus on after selecting the right genetics and optimize feeding. It those pay to have a farm-specific flock health plan.


Thought for the day

We need to use science now more than ever. Science is fast and ever-evolving but it is the basis of making good decisions in farming systems. Let’s utilize the best science and research more.


huge thanks to Nettex for their support in making #50in50 happen, for more information on click here https://www.net-tex.co.uk/products/sheep/sheep-vitamin-mineral-supplements/cobalt-selenium-vitamin-b12-drench

Happy safe farming


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