EweAndNewLamb1I wanted to write a little about the natural process of ewe-lamb bonding. I’d talked to a couple of people this season who had various anomalies happen. And as I watch my own ewes do their thing, and am also managing some ewes inside the barn, I think there are some lessons we can learn from pasture lambing that you don’t find in barn lambing books.

All of the sheep books I have discuss the birthing process in this way: there is usually a whole chapter on dealing with mal-presentation, then there is a brief mention of the “clip-strip-and-dip” procedure, banding, tail docking, then advice to stick ‘em in a jug for three days, and off you go. Very little is said about the mechanisms of ewe-lamb bonding. I suspect that this is the modern way, or the American way. It always assumes that the ewe and lamb will successfully bond, because they don’t have a lot of options or reasons to fail at bonding; they are stuck in a four-foot pen together for 36 hours. Yet, I bet if I picked up some books from many decades ago, written in the UK or Australia, there might be different advice written from the viewpoint of someone watching birth happen in the pasture. It’s on my bucket list to read some old-time sheep books to see.

Behavior Chains

EweAndNewLambsThe bonding process seems very much like a behavior chain to me: in nature, animals are genetically hardwired with certain “chains” of instinctive behavior, where one behavior triggers the next, and so on. These are so hard-coded that often if a link in the chain is missing, the animal cannot proceed with the rest of the behavior. The classic example I’ve read about is in big cats (cheetahs, I think). Their behavior chain to eye orient-stalk-chase-bite-kill-eat is so non-negotiable, that zoos sometimes have trouble getting cheetahs to eat if they just throw them a slab of meat. Instead, they have to put the meat on a string, and literally simulate a game of cat-and-mouse so that the cheetah can deploy the whole sequence of the behavior chain, finally getting to the devouring part.

In domestic dogs, we have genetically tinkered with the wild behavior chain of eye orient-stalk-chase-bite-kill-eat in various ways. It is possible to “drop out” certain pieces of the chain via selective breeding. In Pointer breeds, we have removed the stalk behavior onwards. So Pointers perform eye-orient on birds, and then literally “lock up” and stay stuck in that behavior, never crossing the threshold of flight zone that would cause the bird to move. The piece of the chain that triggers them to stalk and chase is genetically missing (at least in good Pointers!).

CleaningLambsNoseIn Border Collies, we have left in place eye-orient and stalk, but have dropped out the chase and subsequent behaviors. Again, this is true at least in good Border Collies- as many of us have dogs that are happy to chase and bite, and even kill and eat! And, I have one Border Collie who is more like a Pointer, she is termed “sticky” in that she eye-orients to the stock, then just gets stuck there and cannot move into the stalk behavior like I want her to.

In guarding breeds, we have dropped out the kill and eat part. So, guard dogs are happy to bark and chase and even bite, but hopefully stop there, and don’t cause the liability of actually murdering and consuming an intruder on our property!

In some laying hen breeds, we have dropped out the beginning nesting behavior, and the subsequent broody behavior, from their instinctive reproductive behavior chain; rendering nice egg layers which are happy to drop a daily egg in a meagerly bedded box and leave.

The Ewe Birthing Chain

We can see in pasture settings the behavior chain of sheep birth and bonding in a way that may be less apparent in a barn. As birthing comes near, the ewe naturally separates from the rest of the flock (if she has room to do so). As soon as the ewe’s water breaks, the smell of that placental fluid is a huge trigger for her. She will circle that spot in the ground, pawing and licking at the fluids, and talking in her low guttural voice that’s reserved for her lambs.  As the contractions increase and the lamb moves through the birth canal, the ewe will start turning in more circles, looking backwards to see if her lamb has arrived. You can see how this birth canal sensation works when you have to stick your arm inside the ewe to re-position a mal-presented lamb: she will immediately spin around to see what may have come out, triggered by that sensation of something in her birth canal. It’ll happen again when she passes her placenta a few hours later; though she will be able to quickly identify that it’s not a lamb, and she’ll ignore it.

When the lamb is delivered, the ewe immediately starts licking it, consuming more of the placental material and mentally basking in that odor and taste. This olfactory experience seals the deal: that smell will linger on her lamb even as it grows, and this is primarily how she knows it’s her lamb. At this same time, she and the lamb nicker softly to each other, which imprints each other’s voices in memory. If this bonding period goes smoothly, later when the ewe and lamb get separated, they can call to each other to reunite, then smell each other to confirm identity. It’s amazing that even in the cacophony of moving all the sheep, and all the ewes and lambs are calling, they can find each other in the din. If a lamb is isolated and disoriented in the pasture, he will call out. His mother will answer and expect him to come to her. If he does not, and starts issuing more and more shrill pleas, she will become alarmed and go pick him up.

Interruptions to the Chain

So, that is how it’s supposed to go. But the behavior chain for bonding is somewhat fragile, things have to happen in the right order, and the window of time where it works is limited. If there is a lot of chaos happening around the ewe while she’s immersed in this smell and voice memorization process, the process can fail. So, if the sheep are in crowded conditions, and a lot of other lambs are coming and going through that ten-foot “scent cone” radius, the mother can get confused. She will adamantly try to ward off “wrong” lambs, so chaos can cause her to ward off her own lambs inadvertently.

DogHelpingCleanLambIf the ewe feels threatened, she can become so anxious about managing the threat that the bonding process is superseded. Things like a dog chasing sheep during this process, distressing the ewe and moving her away from the location of these birth smells, can also be disastrous.

The most obvious example of interruption to the bonding behavior chain is a cesarean section. Everyone knows that mammals have trouble recognizing their offspring, letting down milk, bonding and being maternal when their young are  unnaturally cut out of the body. This can often be overcome, especially with hormonal injections, but it is an acknowledged difficulty.

Another common scenario of bonding gone awry is if we have to remove a lamb from the birthing situation to rescue it. If a chilled lamb is brought into the house or barn to warm it, and returned to the mother several hours later, it is often too late. The lamb has collected multiple foreign smells, the birthing scene has diminished in its scent intensity, the birth canal sensations are long forgotten, and the window is closed. The ewe no longer knows it’s her lamb and the bond opportunity is lost.

A similar scenario is needing to move the ewe and lamb from the location of birthing too soon. The loss of the intense smells can diminish the olfactory bonding triggers. I have noticed that if I try to make a ewe move right after lambing (for instance to make her choose a grassy place instead of a muddy spot to finish her lambing job) she will resist. She is very drawn to the spot where the placental fluids linger, and is very distressed if her lambs are moved from there too quickly. She will often insist on moving them back!

And,  then there is the reverse situation, where a still-pregnant, passer-by ewe somehow gets sucked into another ewe’s birthing scenario. She gets excited by the smells and sounds, the behavior chain is triggered, and she tries to claim one or more lambs for her own. This could be a mild and harmless fancy, or a downright obsession that has to be stopped before it wreaks havoc on the situation of both ewes.

The other interesting aspect of this bonding behavior chain is how we can sometimes sneak in an orphan lamb and have another mother accept him as her own. If the orphan is covered in the appropriate birthing fluids and magically turns up at the scene of the birth, often we can fool the mother into thinking it’s one of hers. There are variations on making this method work: getting the orphan lamb completely wet, covering him in the skin of a dead lamb which did belong to the mother, or putting a menthol rub on the ewe’s nose to confuse the scents a little bit while the bonding window is open. The ewe may sense that something is a bit peculiar, but the behavior chain is strong, it marches along and convinces her to go with the flow.

Protecting the Bonding Window

We don’t usually want to end up with bottle lambs, so it’s important to try to protect this narrow bonding window and prevent things which could interrupt it. Giving the ewe space to isolate herself is the first factor. If space is limited, then jugs can provide a physical and visual barrier to allow the ewe to focus on her job. Ideally, the ewe should be jugged before she lambs, so she isn’t taken away from the birthing spot to be put into a jug. Quiet and stability are the other elements that allow a ewe and lamb to finish bonding. Moving a rotating pasture, or introducing other changes needs to wait until the ewe and her lambs have had that window of time to themselves.

Some people I know are fastidious about not disturbing the ewe in any way during the first day, including not letting anyone touch or hold the lambs. I feel this is a bit extreme- I expect my ewes to tolerate me handling the lambs so I can process them- weigh, tag, iodine the naval, and administer oral vaccine. If ewes are too psycho to cope with this, then they are not good ewes. And within hours, I expect the bonding to be solid enough that  a visitor can hold and pet a lamb without disturbing the bond. And usually by this time, the ewe can cope with the flock being moved a short distance, such as rotating the pasture to a next-door square. Moving longer distances can create quite a drama, though I’ve done it when I had to. This year, I’ve added the complication of a doofus guardian dog licking the newborn lambs, but she doesn’t seem to bother the ewes at all. They mostly consider her an environmental factor to be ignored.

Despite our best efforts, sometimes things happen which cause the bond to fail. If this happens, some people have luck jugging the ewe with her lambs, or even tying her head or putting her in a stanchion, and waiting a few days for her to give in and accept a rejected lamb. I’ve had this both succeed and fail. In the meantime while trying, it’s wise to supplement the lamb with a bottle. This will ensure the lamb has the strength to keep attempting to nurse off its dam, and also ensure it’ll adapt to the bottle later if it does become an orphan-rear.

What anomalies have you had in the ewe-lamb bonding process?

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