A Detailed Look at Dog Pregnancy
Fertilization (British English spelling: ‘conception’) is the process by which a male sperm enters a female egg and mixes it with chromosomes. The result is a diploid zygote.
The zygote grows into an embryo. The fetus is then ready to be born. During the first month of pregnancy, fetal development is very rapid.
Fertilization
Fertilization is the fusion of a haploid male gamete (spermatozoa) with a haploid female gamete (ovum). It occurs when the nuclei of the two cells combine, producing a diploid cell known as a zygote.
Fertilization is species-specific and depends on the chemical properties of an egg’s surface, called the zona pellucida. This membrane contains sperm receptors that match up with human sperm, and it binds with sperm when it reaches the egg.
Embryonic Development
After fertilization, the zygote undergoes numerous cleavages and grows into a blastocyst. The blastocyst then implants in the uterus, where it becomes a syncytiotrophoblast, and is enveloped by the endometrium.
In the 3rd week, the embryo undergoes gastrulation and ectoderm, mesoderm, and endoderm germ layers begin to develop. These germ layers transform and differentiate to all of the tissues and organs in the body.
Early Pregnancy
When a dog is first pregnant, she’s usually not showing any noticeable symptoms. However, early symptoms can include a change in appetite and nausea.
Pregnancy can also be accompanied by an enlarged belly. This is due to the fetuses growing in her stomach.
Second Trimester
During this trimester, your baby starts to look more like a child. Their facial features align, and their fingers and toes are well-defined.
This is a very exciting time in your pregnancy. It’s also a time when you can begin to feel your baby moving inside of you.
Third Trimester
The third trimester is when your body and baby are in full-on, busy growth mode. They’re putting the final touches on everything from brain development to neuron formation.
In addition to all the physical changes, your hormones continue to change preparing your body for labor and delivery. This can make some of your pregnancy symptoms worse, including fatigue and frequent peeing.
Fourth Trimester
The Fourth Trimester is the time when your Bulldogology begins to show signs of pregnancy. Her nipples (the glands along her mammary chain) will enlarge, and her belly may become pink.
Your vet can confirm your dog is pregnant by using an ultrasound. This will allow her to see the developing fetuses in her belly and check their heartbeats.
Fifth Trimester
A dog’s pregnancy typically lasts for 62 days, plus or minus two days. During this time, the fertilized eggs embed themselves into the uterine lining and begin to develop into recognisable puppies.
During this period, your dog’s appetite will increase and her nipples will enlarge. She may also start to shed her hair as the fetuses grow beneath her skin.
Sixth Trimester
The six-month dog pregnancy trimester, which begins in weeks 22 to 28, is a busy time for both you and your dog. During this period, fetuses develop their sex organs and start to look more like puppies.
This trimester can be stressful for your dog, so it’s important to take care of her and provide her with the nutrients she needs to give birth safely.
Seventh Trimester
The seventh trimester is a busy time for both you and your dog. Your baby grows and develops at a rapid rate, and your belly is likely to be a size larger than usual.
Your body may also go through some ’11th hour’ changes that your dog will pick up on, such as Braxton-Hicks contractions or drops in your blood pressure. These may result in your dog becoming extra clingy and protective of you.
Eighth Trimester
The Eighth Trimester is the last of the three main trimesters. During this time, the fetus is growing rapidly and developing essential organs and systems for a healthy pregnancy and birth.
The fetus also begins to develop a skin, hair and nails that cover it from head to toe. It may also develop lanugo, peach fuzz-like hair that helps keep it warm.
