Wednesday, March 11, 2015

How to Pill a Dog

Here is a technique for pilling a dog without getting your fingers crushed between the dog's molars. Try this technique if your dog manages to spit out the pill no matter how you disguise it, or if the pill disintegrates too quickly for any other means of delivery. The technique should work with medium or large dogs. I don't know how well it works with small dogs.

I was able to train my shar-pei mix to enjoy pilling for many years, although later in life it became less fun again. My cattle dog mix never cared for the pilling, but she is happy to get it out of the way because I always reward her with a meal afterward.

Cardinal Rules

The most important rule when pilling a dog is that the dog should be happy to have participated by the end. Praise her each step of the way for even the slightest bit of cooperation. For a dog, praise is an excited, happy tone. The words you use hardly matter. Praise especially when you're done.

The corollary of this rule is that pilling a dog should not be a fight with the dog. You may have a brief struggle, but if the pill doesn't go down with little struggle, it's best to take a break, praise the dog for trying, and then try again a few minutes later.

Holding the Pill

The technique presented here has a few variations. The first step is to pick up the pill. There are two ways to hold the pill. Initially, when the dog isn't willing to open wide, I hold the pill between my index finger and my thumb and lift my other fingers out of the way. The hand should look like a deer with antlers, as in the following photo:

As the dog gets used to being pilled, you might relax your fingers and hold them more like a fist, as in the following photo:

The illustrations below show the hand with free fingers in a fist in order to reduce the size of the images (and the effort required to draw them). The deer antler posture is probably easier at first.

Positioning the Dog

For this procedure, I find that the dog must sit in front of you facing to the side. If you are holding the pill in your right hand, the dog faces to the right, and if you are holding the pill in the left hand, the dog faces to the left. The procedure does not work if the dog is facing you or facing away from you. Here is what this looks like:

The dog must be sitting. It is hard to notice in this photo, but the dog's tush abuts my knee. This keeps her from scooting backward. The dog can also sit against a wall or anything else that's handy. I have many pills to give my aging dogs, so I usually put the pills in a little dish, position the dog as you see above, and then grab each of the pills in turn.

Opening the Mouth

Once the dog is in position and you have a pill in hand, holding the pill using one of the above techniques, place your hand over the dogs muzzle as you see above. Press the jowls or lips of her upper jaw into her mouth, below her teeth. This causes my dogs to open their mouths just a little, because they don't want to bite themselves.

If pressing the jowls into the mouth causes the dog to open her mouth enough for you to slip your index and thumb in, proceed to the next step. Otherwise, slip one or  two of the free fingers of the hand that holds the pill into the front of her mouth. She may then quickly open. She may require that you place a little downward pressure on her lower jaw to get her to open.


When she opens her mouth, quickly perform one of two possible procedures: pilling down the middle or pilling along the side. Pilling down the middle works for one of my dogs, and pilling along the side works for the other. You'll need to experiment to see which procedure works best for you and your dog.

To pill down the middle, move your hand into her mouth straight-on, with the index finger and thumb that are holding the pill moving straight in. The fingers and pill move in the direction from nose to throat, as show in figures (1a) and (2a). In step (2a), you have the pill in the dog's mouth somewhere between the rear molars. In this position, if you are making deer antlers with your hand, were you to close your free fingers, you'd be wrapping them around the dog's lower jaw.

Once have the pill in as far as you can go, slip either your thumb or your index finger forward in order to flick the pill toward her throat. Figure (3a) illustrates thrusting the index finger forward to flick the pill in. Remove the hand straight out the way it came, as shown in figure (4a), and proceed immediately to the next step: holding the nose up.

The above pilling procedure does not work well for one of my dogs, as she'll usually spit the pill out. For this dog, I move my hand into her mouth at an angle, as shown in figures (1b) through (3b). My hand starts on the far side of the dog relative to me (1b) and moves toward the back of her mouth (2b), toward me. These two steps are similar to the prior procedure, but the next step is different: move the index finger forward to slide the pill along the inside of the rear molars, between her tongue and her teeth at the back of her mouth, as shown in (3b). Remove the hand directly out of the dog's mouth, as shown in figure (4b), and proceed immediately to holding the nose up.

Holding the Nose Up

As soon as you have placed the pill at the back of her mouth, immediately move your pilling hand to under her chin and gently point her nose up to the ceiling. She should be sitting to make this easier for you to accomplish and more comfortable for her to experience. Holding the nose up helps the pill to go down, and waiting a few seconds helps ensure that it stays down.

Hold her in this position for a few seconds, speaking nicely to her. You don't want to excite her too much now, because you don't want her jolting away. I'm told that with some dogs, gently stroking the throat helps the pill to go down, but I've never noticed this making a difference in my dogs.

Do what you can to make this an enjoyable part of the experience. One of my dogs likes kisses and face time, so I kiss her muzzle and look into her eyes. She also seems to like me rubbing between her eyes. My other dog just likes to be spoken nicely to, so that's all she gets for this.

One of my dogs usually licks her chops when the pill has gone down, so when I'm unsure, that's my clue that she's done. I can sometimes see my other dog swallow.

If you failed to get the pill at the back of the throat prior to this point, I find that holding the nose up rarely makes the pill go down. Instead, the pill just dissolves during this time, tastes really bad, and makes the dog less cooperative for the next attempt. Better to retry a false start sooner than later.

Praising and Rewarding

Never forget to praise the dog after you're done, particularly as you're getting them used to the process. Give her the kind of praise that she registers. They also love treat rewards. I often pill before feeding, so the meal serves as a reward for enduring the pilling process.

If you are administering multiple pills, I find it necessary to withhold the lavish praise until after the last pill, because the praise seems to mean, "Yay! You did it! You're free now!" Don't pill too fast, as it may take a number of seconds for each pill to go down.

Summary of Steps

For your convenience, here is a summary of the steps of this technique:

  1. Hold the pill between index finger and thumb in one of the above two postures. Pose the hand like a deer with antlers if the dog won't open far or you hand is too big to fit in her mouth.
  2. Sit the dog cross-wise in front of you, facing toward the side whose hand has the pill. Block the dog's tush so that she can't easily stand or back away, such as with your knee.
  3. Praise the dog for her cooperation, and speak to her as if this were going to be fun.
  4. With your other hand, gently press the dog's jowls under her teeth to get her to open her mouth.
  5. If the dog doesn't open her mouth far enough for you to slip your pill fingers in, slip the free fingers of your pilling hand into the front of her mouth, possibly with a little downward force.
  6. When the dog makes a quick move to open her mouth, quickly slip the index finger and thumb that hold the pill into the back of her mouth, between her rear molars.
  7. Flick the pill toward her throat by thrusting either your index finger or your thumb forward. Or press the pill forward with your index finger to slip it along the inside of her molars at the back of her mouth, between the teeth and the tongue.
  8. Remove the hand straight out of the mouth to avoid getting fingers between the molars.
  9. Immediately move the hand that inserted the pill to just under her chin and gently—but quickly—point her nose toward the ceiling. She must be sitting for this.
  10. Do something that the dog likes while you're holding her nose skyward, whether it's talking sweetly or giving special rubs or kissing her where she likes to be kissed.
  11. Praise her lavishly when you are done, possibly reward with a treat or a meal.
Just don't forget the cardinal rules: (1) by the end of the process, the dog should have found the experience net positive, and (2) pilling should never be a fight between you and your dog.

Wednesday, January 7, 2015

How Spiders Get Bigger by Molting

It had always been a mystery to me how arthropods manage to get bigger by shedding—or "molting"—their exoskeletons. If you're molting an exoskeleton, you're losing mass, right? It makes more sense that an arthropod would get smaller by molting. I've seen spiders before and after molting, but it wasn't until I witnessed a large spider molting that I finally understood what was going on. It turns out that I had seen the process before when a butterfly emerges from a chrysalis.

It is most apparent that a spider's legs get longer after molting. Here are two photos I took of a spider in 2011. Both photos are of the same spider, taken two days apart. The bottom photo is of the spider prior to molting, and the top is of the spider after molting. The measurements given are the lengths of the first legs. The two photos are proportioned correctly relative to each other, so you can visually compare the before and after sizes.

The spider is a male Mecaphesa dubia, which is a kind of crab spider (family thomisidae). In most spiders, the legs get just a little bit longer with each molt, but in male Mecaphesa crab spiders the front legs instantly become very long legs upon molting into adulthood. This spider's front legs became 60% longer in a single molt. I'm not sure how it helps them to have such long legs, but I can attest that the adult males can jump high and far to get away from danger. The long legs may also help the spider to keep a grip on the female while mating.

Mandy Howe, a highly knowledgeable "amateur" arachnologist and the spider smarts behind the public resource, offered this explanation back in 2011:
I think the new exoskeleton is folded up inside the old one, then when the old is shed off, there is a period when the new exoskeleton is rubbery and expandable... the spider pumps hemolymph into it and expands itself to full size, completely filling out that new exoskeleton that grew all curled up under the old one.... at least that's how I think it happens.
Since 2011 I have seen spiders molt many more times. It wasn't until I watched a large spider molt that I could see much of what was going on. I have now seen Mandy's explanation in action. I photographed a large Holconia immanis huntsman spider molting, which you can see in this photo series. Here is one photo from the series:

Here is how a spider gets bigger by molting:
  1. The spider first fattens up its abdomen. A spider's abdomen does not have a hard exoskeleton like most insects do. Instead, it is soft and expandable. The more the spider eats, the bigger the abdomen can get.
  2. The outer exoskeletons separates from the newly formed inner exoskeleton. When this happens, the spider becomes inactive. The exoskeleton also tends to darken when this happens, at least in crab spiders. Notice how dark the legs are in the above photo of the Mecaphesa prior to molting.
  3. The spider hangs from a thread. Not all spiders do this, but the araneomorphae that I study do. Tarantulas do not hang from threads, and I don't know the particulars of their process.
  4. The spider pumps hemolymph from the abdomen into the cephalothorax. "Hemolymph" is just bug blood. The "cephalothorax" is the spider's head. A spider's legs are on its head.
  5. The pressure from the hemolymph in the cephalothorax causes the top of the cephalothorax—the carapace—to lift off. In particular, a seam at the back of the carapace breaks, while the front of the carapace (around the eyes) remains attached and becomes a hinge. You can see the carapace hinged forward in the above photo of the Holconia immanis.
  6. The spider pulls out of the old cephalothorax while continuing to pump hemolymph into the cephalothorax and legs. In a big spider, such as the one above, you can see a pulsing of the pumping action, although this could also be the spider regularly convulsing muscles to pull free. New, soft legs pull out of the old legs. Because the new cephalothorax and legs are soft, pumping hemolymph into them causes them to expand. Hanging from a thread allows gravity to assist the spider in pulling free.
  7. Once free of the old exoskeleton, the spider hangs limp, with the legs below it, presumably to allow the spider to continue pumping hemolymph into the legs to expand them to full length.
  8. The spider then repeatedly flexes and extends the legs, presumably to mobilize the joints.
  9. Finally, the spider takes a normal spider pose and waits for the new exoskeleton to harden up. The soft exoskeleton is normally light or pale, and it darkens as it hardens. During this phase, the spider is prone to being eaten by predators, because it can't readily defend itself. I have to be careful not to let crickets near a molting spider, because the crickets may eat it all up.
You can see many of the above steps in the photo series I posted. At the end of this process, the spider has longer legs and a bigger cephalothorax, but because it has been pumping hemolymph from the abdomen into the cephalothorax, the abdomen is much smaller. As you can see in the before and after photos of the Mecaphesa celer, above, the abdomen is much smaller after molting. Notice also that not only did the Mecaphesa's legs get longer, but its cephalothorax got bigger too.

So the mystery is solved, and it turns out to be nearly identical to the process of a butterfly emerging from a chrysalis. The butterfly pumps hemolymph from its abdomen into its thorax and breaks open the chrysalis. It then pulls free from the chrysalis, continuing to pump hemolymph. Hemolymph pressure increases the size of the butterfly's thorax and wings, just as it increases the size of the spider's cephalothorax and legs. In the end, both the butterfly's wings and the spider's legs become full size, and both the butterfly's and the spider's abdomens are smaller. Both then wait for their new bodies to dry. However, unlike the butterfly, if the spider is not yet an adult, the spider will go off eating more, growing its abdomen to an even large size, and eventually molting again into a still larger spider. The spider repeats this process until it is an adult.

This post is preparation for my next post, which will be about how spiders regrow lost legs.

(Some notes: Because I don't study tarantulas, I don't know how their process differs. I do know that they often molt by lying upside down, not from a thread. Tarantulas also molt once per year as adults. I don't know if this is true of mygalomorphae in general, which is the group to which tarantulas belong. Also, butterfly caterpillars molt periodically in a similar but less spectacular process.)