How to Whelp Large Breed Dogs
To whelp large breed dogs, buy a whelping box from a store or build your own from wood or cardboard. Either way, make sure the whelping box is big enough for your dog to comfortably lie in and its sides are tall enough that the puppies won't escape. When the puppies start to come out, the mother should lick the placental sac from their faces, but if she doesn't do this within a few seconds, you should gently rub it off with a damp cloth. She should also gnaw at the umbilical cord, but if she's struggling, you should cut it with a sharp pair of shears.
Prepare the whelping box. The whelping box is the space in which your dog gives birth to its puppies. It is also the space to which all puppies should return after their mother has completed birthing its litter. You can buy a whelping box commercially or construct one from wood or a cardboard box. If you think your dog will become pregnant again, you might as well invest in a sturdier commercially-made whelping box. These are readily available at most pet stores. If you don't foresee your dog bearing more pups, you can make your own whelping box and then simply discard it once it is no longer useful. If you're handy you could construct one of wood. If you're less handy, you could simply take the top off a cardboard box that could accommodate your dog (for large breed dogs, you'll need an area of at least one square meter, or nine square feet). For large breed dogs, you'll need a large whelping box. If you construct your own whelping box, ensure that it is large enough for the dog to lie down and turn around comfortably. A rule of thumb is to measure around your dog when she is laying down fully outstretched and then add an additional foot to these measurements. The sides of the whelping box should be tall enough that puppies cannot escape, but low enough that your dog can hop in and out comfortably. For instance, your box might have three sides that are 15 inches high (38 centimeters) and one side that is 4 inches (10 centimeters) high. Do some research into how large puppies usually are for your breed to get an idea of how large the sides need to be. Since you have a large breed dog, there will be enough space in the whelping box for you or another caretaker to sit with your dog and comfort it during labor. Depending on what breed and how large your dog is, a baby pool can often be used as a whelping box. Line the whelping box. Your whelping box needs to be soft and cozy inside for your new puppies and your large breed dog. Place a large plastic bag in the bottom of the box. Place layers of newspaper and/or a few cozy blankets or sheets over the bag. Never add wood shavings, sand, or other particulate to the whelping box. Don't add anything small enough that the puppies could get them lodged in their mouths. After being born their eyes will still be closed and they will be constantly searching to suckle. Place a heat lamp above the whelping box. The lamp should be suspended over one corner of the whelping box so that pups can move toward or away from it depending on their temperature preference. Newborn pups have a lower core body temperature than adult dogs and are extremely sensitive to temperature changes. Aim for a whelping box temperature of 85 degree Fahrenheit. Give your dog a trim. Birth is always messy. Whelping means not only new puppies, but amniotic fluid, placental sacs, and umbilical cords, all of which have their own unique juices. These birth liquids are difficult to get out of matted dog hair. You can easily avoid the unpleasant task of scrubbing your dog's rear legs and tail by trimming the hair in that area at least a few days before labor is expected. Use your knowledge of how far along your dog is in its pregnancy to determine when to trim it. Remove hair in the area of the vulva, the rear legs, and tail. If your dog has a lot of long hair, you may want to consider shaving her belly or trimming around the nipples to make it easier on the puppies. Assemble some emergency supplies. In case your dog has trouble getting its puppies out and going to the vet isn't an option, you should be ready to intervene on your dog's behalf. Collect three or four pairs of sterile hemostat forceps, sutures, a tube of lubricating jelly, a small bottle of povidone iodine solution, and your whelping manual. Additionally, try to have a more experienced friend present or watch videos about whelping so you know if your dog needs intervention. These common medical supplies can be obtained online or at your local pharmacy. Forceps might need to be obtained through a larger big-box store or through your local medical supply company. In the event that you need to remove a pup from your dog, consult your whelping manual or call your vet and have them walk you through it. You might also want to get a book or deck of cards for yourself so you have something to do while waiting for your dog to deliver. Look for signs that your dog is in labor. In the early stages of labor, your dog might pace, shiver, dig, or vomit. This might last six to 12 hours, after which your dog's amniotic sac – a gray balloon-like bulb, also known as the placental sac – will emerge from your dog's vulva. The sac will appear small at first, then grow in size. Eventually the dog's puppies will slide into this sac, at which point the mother will nibble at it to deflate it. Clean the puppies off. When the puppies are born, they will be covered in a thin membrane – the placental sac – which their mother should remove by licking it off. However, if the mother is too engaged in pacing and concentrating on her labor, you might need to intervene and remove the placental sac yourself. If your dog has not removed its pup's placental sac after a few seconds, take a damp cloth and gently rub the puppy's face. This approximates the natural licking behavior of the pup's mother that should remove the sac. If the sac remains on the pup too long, it might suffocate. Once the sac is off, the pup will be wet with placental fluid. Use a clean, warm towel to dry the puppy off, making fast rubbing motions along the length of its body to help warm the puppies up as well. Snip the umbilical cord. The umbilical cord is a long cord that connects the uterus of the mother to the abdomen of its puppy. During the mother dog's pregnancy, the umbilical cord provides food and nutrients to the growing puppy. After the pup is born, however, the umbilical cord is no longer needed. The mother dog should gnaw at the cord until it is severed, but if she doesn't you should be ready to help. To snip the umbilical cord, measure ½ an inch (1 centimeter) away from the puppy's body, and tie it with thread or unwaxed floss. This will narrow the diameter of the cord, making it easier to cut. Then, use a sharp pair of shears and cut straight through it. If the cord bleeds, tie it with a suture. The two portions will shrivel up and drop off in time. Allow the pups to nurse. All the excitement of being born will make your puppies hungry. Some pups need a brief rest before nursing. Other pups are able to head straight for their mother and suckle their fill. In either case, wait until the puppy has finished nursing and your dog is back on its feet before removing the pup to the incubation chamber. Remember to allow the mother plenty of time to eat and drink lots of water. Feeding many puppies takes a lot of calories so your dog needs more food and water to keep her milk supply up. Move puppies to an incubation chamber. You can easily craft a makeshift incubation chamber by placing a heating pad in the bottom of a laundry basket or medium-sized cardboard box, then placing a heavy blanket over the heating pad. As your dog births puppies, remove them to the incubation chamber until your dog is no longer in labor. Large breed dogs, especially, may accidentally stomp on their own puppies while pacing about in the whelping box during labor. Removing puppies to an incubation chamber is, for that reason, especially important. Try not to overcrowd the incubation chamber. If necessary, create another. Try to keep no more than two puppies together in one chamber. Note the details of the births. When your new puppies come out, you'll need to keep track of who's who. Note all the details associated with the birth in a journal or chart. Assign each puppy a number (i.e., Pup 1, Pup 2, Pup 3…), the time they were born, their sex, weight, and any marking you might have made (some people like to dab a small bit of colored, nontoxic nail polish on their puppies to keep track of which is which). Most importantly of all, make sure that after each puppy is born, the placenta comes out. The placenta is an organ that provides nutrients and eliminates waste of unborn animals. If the mother does not eject the placenta after giving birth, she can get very ill. Normally, the placenta will immediately come out after the puppy is born and the mother will consume it.  But sometimes the placenta might not eject right away, and sometimes the mother might not eat all the placenta. It's possible that your dog will bear two puppies and then eject two placenta. Use the chart to mark down when the placenta come out and contact your vet if your dog does not eject all its placenta. As your puppies grow over the next couple of weeks, use the chart to monitor their weight. Their weights might decrease slightly immediately after birth, but by the end of the week they should weigh twice as much as they did when they were born. If they do not, contact your vet. Change the bedding. Once your dog has finished whelping, take it outside so it can relieve itself. While it's out, change the blankets and other materials lining your whelping box. It will likely have wet layers of newsprint or damp blankets at this point. Remove them along with the underlying plastic bag and replace them with dry materials. Put the dog family together. After your large breed dog is back in its whelping box, take the pups out of their incubation chamber and reunite them with their mother. They may be hungry and want to suckle again. The puppies will remain vulnerable for several weeks and should not be separated from their mother until your vet indicates that it is okay to do so. 
Prepare the whelping box. Line the whelping box. Place a heat lamp above the whelping box. Give your dog a trim. Assemble some emergency supplies. Look for signs that your dog is in labor. Clean the puppies off. Snip the umbilical cord. Allow the pups to nurse. Move puppies to an incubation chamber. Note the details of the births. Change the bedding. Put the dog family together. 