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March 12, 2023

 Successful weaning practises


In August 2022, we had Rob Bell on the Head Shepherd podcast, discussing successful weaning practices


Mark Ferguson: G'day Rob. Rob is the co-founder and chief technical officer at ProAgni, and CEO and principal consultant at Formula Ag.Welcome along, Rob.

Rob Bell: Thanks, Ferg.

That was a hell of a title I have just given you, but I think that means you know a lot about nutrition.

An expert in nothing and broad across most things. Haha. I have had a couple of hats in my life, but currently it's the chief technical side of things at ProAgni and then a consultancy business, which is Formula Ag, whereI'm the sole consultant within that business. Servicing clients predominantly through central western New South Wales in mixed farming production businesses.

Interestingly, I started life as an agronomist specialising in cotton, the other white, fluffy stuff.

Really the early droughts of early two thousands sorted that out pretty quickly for me. I specialised in irrigation production, based in westernNew South Wales. And no water meant not much of an opportunity to conduct much work.

I watched the livestock industry struggle through that time but was lucky enough to work with the local land services vet to provide support to customers and clients at that time around pasture management and supplement programs. That opened my eyes to the opportunities within the livestock sector.

One of the things that really struck me through that was, regardless of what happened, we still had an asset at the end of the day that contained some value. Whereas in the cropping space, we'd put a seed in the ground and if it did or it didn't rain, well, that determined your cash flow for the year.

For me it really struck a chord that livestock is a much more viable long-term business opportunity. Cotton did things very well… integrated pest management… planning… execution.

AndI thought there were some real lessons there that could have been overlaid into a livestock enterprise.

Through happenstances I met up with some guys, and next thing you know, I'm working as a trainer and livestock consultant across Australia.It was an interesting road. I've worked with some fantastic people over the years to get where I've got to.

For the past 16 years I've been focused pretty much in that mixed farming business where it's that combination of cropping and animal integration into those businesses where I've really found my feet as a consultant.

Through that professional development and relationships, ProAgni was born about six years ago. A lucky meeting with a ruminant microbiologist in Queensland, Dr Athol Klieve, and some stranded science that he'd spent a lifetime working on.

This gave us the opportunity and I went back to a client at the time, which was Lachlan Campbell, and said, “We've got an opportunity to do something pretty outstanding here in terms of antibiotic resistance and removing those challenges for the livestock industry. And also potentially methane mitigation into the future.”

So that's been a journey in itself in the last six years where we've taken some pretty complex, challenging science and turned it into a commercial reality. That has been primarily the focus of Pro Agni and for me as well.

Think about the weaning process as a production phase, not just a day on the calendar.

Today we're pretty keen to talk about weaning. You obviously have a lot of experience in weaning and I love the concept that weaning is a process, not an event.

What have you seen as worst practice and what is best practice when it comes to making sure we give young animals the best, best possible start to life post-mum?


I think weaning needs to be looked at in several buckets to break it up. I think firstly there's the physical process of weaning and what systems and processes can we put in place to minimise stress on both the animals and the managers.

Then there's the pasture management side of the equation, that the day we wean is the day we reduce our total demand in the business by 40%for energy. We have a feed reserve being built then and then it's also that economic side. What does that feed cost? What's four or five weeks worth of feed at the other end of the season mean for your business?

So I really sort of break it down into three parts.

The first part is: if we are going to select animals for improved genetic gain year on breeding year, and we're striving to get somewhere, we need to understand that every time we do that, we create a demand for nutrition that increases. So we're putting more pressure on the system, so we need a bigger bucket.

We can sometimes be hypocritical in our choices of where we will spend X, Y, and Z on genetics, and then not be prepared to go the extra yard to support that potential growth or expression of those genetics into the future.

You don't see too many guys that buy a 400 horsepower tractor and pull a 20 foot seeder around.

If you've got the horsepower there, well, why don't we use it?

I think it is the most underutilised part of most businesses. I don't think that genetic expression is reaching 60% of its potential a lot of the time, particularly through that weaning process.

We need to think about it from a personal perspective. If you were 10 years old and you're taken away from your parents and you were put on a plane and you went to a foreign country like Japan, you're asked to eat different food, sit on the floor, not speak the language. And have no social support around you from your cultural background. I think you'd be pretty stressed.

To me, that's what we put lambs and calves through during that weaning process. We've removed them from their perfect supplement source, which is milk. We've taken away their social interaction with mum. We're into them with bikes and dogs and helicopters and people in the yards. We're putting them through manual handling processes in races, in cradles. We're going round and around [the yards] with an animal health program. And then we go and put a bag of cardboard in front of them in terms of a bit of ‘rough hay’ and say well, they'll be right.

I think that's really not fair on the animal. For me it becomes a case of let's get these animals accustomed to us as humans being in their life.

Let's get out there before they get weaned and show them that we are not the big scary ogres we can be, but that we actually have some care and love for them. We provide them some education and training to tell them, “We need you to eat these products post weaning.”

We're actually transitioning from a monogastric, so something that digests food more like a pig, into something that is turning into a ruminant. And that only happens once milk really stops in their diet.

So, understanding that it's a transition of a physiological state as well as a mental state is really important. So keep making sure that we educate those animals to eat what we want them to eat pre-weaning, while they're still on mum. Get that imprinting and training done.

Think about the weaning process as a production phase, not just a day on the calendar.          

We're actually transitioning from a monogastric, so something that digests food more like a pig, into something that is turning into a ruminant.


We have this opportunity to gain weight, to let an animal express its genetic potential, to move forward and be healthy and happy for the rest of its life.

Or we have the opportunity to effectively starve it, imply a lot of stress, create animal health issues as a result of that stress and cost our business a bucket load of money at the same time.

Take weaning as a two or three week process. Let's educate animals to eat. Let's support those animals with good practice in terms of animal health programs, vitamin mineral supplementation and gross nutrition in terms of energy and protein and let them find their own feet.

AndI think we can actually do that much earlier than what the industry expects or traditionally does.


We know that we can actually turn the rumen function on early if we expose them to the right compounds at the right time.


So I encourage most people to wean most years in that 15-20 kilo range, whether it's Merinos or crossbreds and cattle somewhere in the 120-150kilos range.

The reason being is that the economic impact of getting those animals off and under their own steam early is significant from a grass bank and a gross energy saving perspective.

But, it also allows us to get a better handle on the behavior and the psychology of those animals.

So my experience anecdotally is when we wean earlier, those animals are much more settled through the weaning process. I don't think they've learned a lot of bad behavior.

Plenty of good concepts to work through there.

It's a really interesting observation. I remember when I was at uni, I had a professor who sort of got chased out of the quantitative genetics world because he was unpopular in saying that if we don't provide more resources [to improve on-farm production], then genetic gain just doesn't go anywhere- you just widen the gap between potential and reality.

And I think we are very guilty of that. We keep cranking out genetic potential, particularly on a few traits, and then have no way of actually feeding that potential or you’re unwilling or haven't got the process.

And so it's a really good concept. I think that's something people really need to consider when they're setting their breeding objective and deciding they want to have lots of more and more and more. Often you'd be better off feeding what you've got or focusing on traits that aren't necessarily resource intensive but will improve your life in terms of health traits, that sort of stuff.

But that's an interesting concept. What does imprint feeding mean? Is that two or three trail feeds on mum then make sure the lambs are on the trail? How many times do you need to feed them?

I tend to recommend 50 to 70 grams of whatever they're gonna see. If it's a concentrated food like grain, through that last fortnight do it three times a week. Do it Monday, Wednesday and Friday. Just get a run in there.

It's as much about the Pavlov Bell theory… that when I turn up with my bucket and rattle the cage, these animals actually recognise that I'm here to provide some sustenance, not here to chase them around the paddock.

Yeah, I think one of the most frustrating jobs you can ever do is try and train a Merino weaner to eat grain when it's never seen it before. You chase 'em onto the trail and watch 'em walk over it while they're lacking energy. Once you're in that free-fall post weaning and you can't get 'em on the feed and they need the energy because the pasture quality's's a pretty uncomfortable place to be as a sheep manager.

Obviously weaning earlier is something that's a pretty consistent message across our neXtgen Agri network. And we're all fond of that. One of the challenges is the need to provide a high protein feed source. The younger or the smaller the animal, the higher protein requirements are. What's your advice there? How do you get protein into them?

We tend to use some pretty specialised supplements for that process. When we start weaning at day one, on a 15-17 kilo lamb, we know nutrient requirements are around 20-21% crude protein in that diet.

We actually meet that with things like high quality plant meals, canola meal, soybean meal, cotton seed meal combined with potentially milk powder (in a dry form) just to get those fats, but also acts as a really nice palatant. So this is something that the lamb's sense of smell is quite familiar with so you get intake very quickly.

As they move on from being a monogastric where that 20% crude protein is required, through the process over that 14 days and rumination really starts to kick in, we actually see that protein requirement dropping quite quickly. So by the time we're at the end of 14 days the requirements could be back to 16 or 17% of crude protein because of the amount of fermentation taking place in the microbial process of dead bugs turning into good quality amino acids and protein sources for that animal.

So it's really a focus of- and this is why it's a process-transitioning acid and enzyme digestion of a monogastric through to afermentation process. And the best way to drive fermentation is to actually get highly fermentable carbohydrates in there. So your barley and your starchy grains, corn and triticale. If we can increase the microbial population very fast, it has a twofold effect.

One is to increase the amount of total energy and those live bugs creating that energy actually turn into dead bugs, creating that protein.

But at the same time the chemistry that those bugs produce in terms of volatile fatty acids determine the architecture of the rumen, and so the amount of surface area and the amount of blood flow coming to that rumen for absorption.

We know through some Penn State uni work from years ago that exposure to starches through that weaning process can really drive papillae development on that rumen wall and blood supply.

So lifting and shifting those nutrients being supplied is the second part of the transition we need to manage, not just get 'em off mum and onto grass..

I think that's one of the key things. It's kind of obvious, but easy to forget that we're dealing with, well…ruminants live off dead bugs.

They're not actually living off the barley feed, they're living off the population of bugs that that creates. That's really the art of ruminant feeding - always thinking that it's gonna take time for those microbes to evolve to a new feed source.

And it's a couple of weeks for them to transition and therefore you have to be careful with swapping feed sources all the time.

Absolutely and I think we need to get away from looking at it and seeing the animal. We need to look at it and see a home brew kit really. Because that's effectively what it is. It's a 15 to 17 litre fermentation chamber in a sheep that is purely designed to digest indigestible foods.

So we've gotta support those microbiomes and get the good bacteria up as quickly as we can because they're our money makers really. So expression of all these genetics is all determined by activity of bacteria.

Yeah, that's an interesting, interesting field for sure. We hear yard weaning sort of referred to. What is yard weaning and do you recommend it or not?

I think the definition of yard weaning needs a slight refinement.

If we get good education and repeated feeding while they're still on mum, yard weaning periods can certainly decrease. For me, it's a case of let's get 'em educated well, let's get 'em in and processed from an animal health perspective. They've got to have access to good, clean, fresh water, and they've lots of space around that quality food that you want to put in front of them. That period can be anything from two days to two weeks, depending on how well those animals have adapted.

And the better the imprinting is done, the less time they are in confinement. I don't like confinement feeding and starving because all that does is induce more stress. And stress is our enemy in this process.

Stress is what causes the secondary snotty noses and pinkeye and coughs and respiratory issues and scours.

That's all an indicator of stress. So, the less stress we have, the less animal health problems we have. But it also affects you later down the track as well. Things like cortisone and adrenaline impact the way that the meat to muscle ratios start to form over time. And by the time those animals catch up, you get feedback from people going “The processors said they're over fat with a fat score five.”

If you actually trace it back, you can actually see at times where the stress event of weaning has actually caused those animals to lay down subcutaneous fat in preference to muscle. And it doesn't matter whether they're a terminal or a reproductive animal. We can get through a weaning process and have one to three kilos gain, rather than one to three kilos lost. That potential six kilo differential, when it comes to a ewe joining, is make or break in the scanning screen.

So there's a lot of points that get driven off our management at that point intime.


Exposure to starches through that weaning process can really drive papillae development on that rumen wall and blood supply.


One thing I've heard Nigel Kerin talk about, which may have come from you, is feeding Beachport Green Cap for things like high magnesium to reduce stress. Is that your recommendation?

I think it's a good product. It certainly does help with appetite and mitigate some stress. But it's one of those things where there is definitely stress mitigation, but it still doesn't replace the need to have volumes of quality food.

A 14-15 kilo lamb…they don't eat much, so what they do eat needs to be good quality. We need to be targeting that high starchy content and we need to be targeting good quality high protein levels.

To get that great rumen development, does it need to be pure starch? I feel like there's mixed messages out there, whether it has to be pure barley or whether they can have something else in the diet to get those photos of the rumens as you see which are full of papillae and look amazing.

Yeah, look, it's all about the bugs.

We're trying to skew a fermentation pattern that drives more propionic acid rather than acetate and butyrate outta the system. And the most efficient energy source that'll do that are starches based out of white grain. Corn, wheat, barley, and triticale. They're the most efficient starch sources that are available on-farm, in our world, to actually drive that propionate production, which actually stimulates the papillae development in that rumen development.

On some farms you see someone will plant 50 acres of turnips or brassica or whatever and then they've got 50 acres of something else. I feel like sometimes lambs are going on there and they might just get adapted to that feed and then that feed runs out and they're onto another one.

If you're going to have a feeding system, you have to always think, “Have I got a rotation here? Can I keep them on that same tucker for a couple months?” Otherwise they never actually settle their rumen?

The thing about the rumen is, it never gets bored. So we need to think about these bugs. They've got a life of three or four hours on average, and it's a population game. So there's bugs that like energy. There's bugs that like protein. There's bugs that like fiber.

If we go in there and graze a brassica crop, for example, we know it's high in protein and it's got high levels of things like potassium. So we've got some complications around digestion because of its mineral composition, but it produces high volumes of high protein food.

So it's fantastic, but we then skew the population to become a population that loves to live on protein, and it's not a balanced relationship within that microbiome.

So, my take on that is… A little bit of supplementation of a starchy grain through that process does two things. One is it gets that mix between protein and energy coming in a little bit more balanced. Secondly is that a small amount of grain can actually drive feed efficiency and also act asa sparing mechanism. So we can add 30 to 40% to our grazing window through small amounts of supplementation.

You quite often see self feeders in the system where if we can go and drop 150-200 grams of cereal grain into the diet, whilst they're on a brassica crop, we get an extra four to six weeks out of that same brassica crop.

The lambs have grown better and there's been less animal health issues because fermentation has been more stable and the bacteria have been more accommodated for what they require, and they all require a starch source for reproduction.

That's one thing they all have in common - all these bacteria need some fermentable carbohydrates to reproduce.

One of the best practices I see over this way and New Zealand is Gundy (David) Anderson. He weans the ewes out of the pasture essentially. They migrate onto a Pivot as a team. Mum and lamb are going around for a while and then he takes the ewe out and keeps the lamb going round. That's on a high protein diet, either clovers or lucerne with a bit of a balance. Is that close to best practice?

I think so. You've got high quality food under those animals.They've been taught to eat because they've been standing shoulder to shoulder with mum, so they're not unfamiliar with the food source.

And then because their nutritional requirements are being met, they're not hungry. They're not thirsty. So when mum gets removed and there's no milk source, they're not going, “Mum, where are you? I'm hungry. I'm thirsty. I'm walking the fence looking for you.” It becomes psychological. If their needs are met, their requirement for mum decreases. If we can get animals well educated to high quality feed pre-weaning, that's best practice.

I think we need to get away from looking at it and seeing the animal. We need to look at it and see a home brew kit really.


I'll never forget in 2009. It was the first time we did ewe lamb mating in Merinos in WA, and we had fed the ewes and lambs on pellets (it was a terrible year). We weaned those lambs onto the pellet they'd been seeing and if you looked at the weight gain graph, you couldn't see where weaning was.

There was not a dent at all. They just kept growing at the same rate they had been pre-weaning.

Weaning should be not traceable on the growth curve. It should actually spike up, I think.

Yeah, get mum off and stop her giving you worms for a start.

I think the average in Australia is the rams are in for nine weeks, which is a bit scary. Obviously we're aiming for a short window of joining so you can have a short window of weaning, so that all of those processes come together rather than dealing with animals that are in a completely different metabolic state all the time.

I'm sure you'd be pretty keen on some short joinings. If you do get that tail of lambs, we always suggest taking those really little ones off. Put them into weight ranges so they're not getting bullied and you can actually manage those smaller ones.

What are your recommendations around splitting those animals up?

For me, it all starts at scanning to be honest. I do recommend that we do earlies and lates and twins and singles, so we can actually get some handle on who's who in the zoo. It does make labour resourcing through that weaning and lamb marking process a hell of a lot easier because we've got identified cohorts together.

In terms of when it gets to the process of weaning, it's very much like with like. I don't like to see big variations in weight ranges within cohorts. If we can have groups, and this is all infrastructure driven, that go three ways - of tops, the average and the tail - it does make life a lot easier.

And then we can apply that appropriate management to those lighter animals, particularly where we might keep supplementation up longer or we might have a slightly tweaked program to accommodate them.

And it's also that social factor, I mean, I'm 6 foot and 120kilos. If I go to the buffet with a jockey, I know who is gonna get the better food. It's that bullying effect.

On the crossbred side of things, they'll be a lot harder on their cohorts around them. I like to see crosses a bit tighter [of a cohort] if we can. Merinos seem to be a bit more timid on the feeding side of things, but if you watch crossies they'll bash and barge and be a lot harder on their pals that are a bit smaller. That's only anecdotally, though.

The industry message of 40% of mature weight for a weaning weight is obviously heavier than what you are suggesting. My understanding of that number was that it was when the rumen was developed enough to handle the cellulose.

But, through targeted nutrition and being careful, you can obviously take 'em lighter than that and we know that from lots of experience.But what does that 40% mean, and should we ignore it?

I guess I look at things a bit more holistically from a business, grass and management perspective. The least time we can have ewes and lambs together, because as you said they're worm taxis, the better life becomes for everyone involved.

We know that we can actually turn the rumen function on early if we expose them to the right compounds at the right time. And that's the focus for me, really. Let's take what can be best practice in terms of grass budgeting, labour allocation, animal welfare and animal production and performance.

Let's tie all that together so that we can make a business really thrive, not just survive.

I guess theoretically, yes, it may be 40%, but what impact does that have on the external parts of the business? Is it food resources? Is it labour use? I'm much more in the bigger picture than that.

Yeah, great point. You've got a heap of different moving parts in a business, and in particular a livestock business. So whilst you might optimise weaning weight, something else is falling off the tree. It's about trying to bring all that together which is obviously what we're talking about.

That's been a really interesting chat, Rob. I'm sure those out there are gonna really enjoy it. I really appreciate your time today and fantastic to hear all those tips on weaning.


Sophie Barnes
Article by:
Sophie Barnes

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