Coco’s Experience With Milk Fever: When Low Calcium Complicated Labor and Nursing

Coco's nursing puppies

A couple of days before Coco’s due date, I noticed that she was shaking.

Because shaking can happen as a dog gets close to delivering puppies, my first thought was that labor had started. I checked her temperature and it was between 98°F and 99°F. A temperature drop like that can happen shortly before labor, so I started watching her closely.

Coco continued shaking throughout the entire day and into the night.

I had seen some trembling with my other dogs during labor, but usually it became noticeable shortly before the first puppy was born. With Coco, the shaking just kept going.

She was also showing some other early signs of labor, including digging in her whelping box, so I kept expecting the first puppy to arrive.

But it never did.

When I Knew Something Wasn’t Right

By about 5 a.m. the next morning, Coco had been shaking for many hours without progressing to active labor or pushing.

She was also starting to look tired.

At that point, I decided that what I was seeing had gone beyond normal labor watching and took her to the emergency veterinary clinic.

One of the things the veterinary team checked was her blood calcium.

That turned out to be an important clue.

Coco’s ionized calcium level was 1.01 mmol/L, below the clinic’s reference range of 1.21–1.45. The medical record listed hypocalcemia, prolonged stage-one labor, panting and tremors among the problems they were evaluating.

The veterinarians gave Coco calcium intravenously, and her calcium level began to improve. After the first treatment it had risen to 1.20.

I learned that calcium is important for normal muscle contractions. When calcium becomes too low, a mother dog can become weak, tremble, and have difficulty with labor.

Watching the Puppies Changed the Decision

Moon and Treat in the incubator after being born

The veterinary team also used ultrasound to monitor the puppies’ heart rates.

After Coco received calcium, most of the puppies had heart rates around 190 beats per minute. One puppy, however, had dropped to approximately 140 beats per minute.

That was concerning enough that the veterinarian recommended an immediate C-section rather than continuing to wait for Coco’s labor to progress. The concern was that this puppy was becoming distressed and that the others could begin declining as well.

I completely understood and agreed.

While we were making decisions about the C-section, the veterinarian also asked whether I wanted Coco spayed during the surgery.

That was a harder decision, but in many ways I had already been thinking about it.

Deciding to Retire Coco

Coco seemed much more physically worn down by her first pregnancy than my other moms had.

After that litter, it took her a while to get completely back to her normal strength. Because of that, I gave her more than a year off while I raised litters with my other moms, who seemed to handle pregnancy and nursing much more easily.

Seeing Coco struggle again — this time with low calcium during labor — made the decision much clearer for me.

Even though Coco is only four years old, I decided that she had done enough.

Her job now is simply to be our family dog, along with being a very good aunt and grandmother to the puppies raised in our home.

I would rather retire a dog early than continue breeding her simply because she is technically young enough to have more litters.

Six Girls Arrive

The veterinary team delivered six puppies by C-section — every single one of them a girl.

Five of the puppies responded normally after delivery with warmth and stimulation. They began moving, vocalizing and showed normal nursing reflexes.

The sixth puppy had a much more difficult beginning.

Her heart rate was only about 20 beats per minute when she was delivered. The veterinary team immediately began working on her.

They didn't give up.

Eventually, we heard her screech.

That little sound was a very big deal.

The team performed an ultrasound of her heart and lungs and saw some concerning findings. There appeared to be a developmental abnormality in her heart with abnormal blood flow, and she had also inhaled some amniotic fluid into her lungs. She initially did not have a suckling reflex either.

The veterinarian explained that her chances of survival were lower than those of the other puppies, but there was still enough reason to give her a chance.

We named her Spirit.

Spirit with big sister Judy

And, at least right now, if you watched Spirit crawling around with her sisters, you would never know what her first few minutes of life looked like.

We are continuing to monitor her closely and will follow up on her heart as she grows.

Learning About “Milk Fever”

Before this experience, I mostly associated calcium with nutrition. I hadn't realized how dramatically low calcium could affect a mother dog around pregnancy and nursing.

Eclampsia in dogs — sometimes called milk fever — occurs when a mother's blood calcium becomes dangerously low. It is especially associated with nursing mothers because producing milk places a large calcium demand on the body.

The clinic explained that early signs can include things such as restlessness, heavy panting, stiffness and muscle tremors. Severe cases can progress rapidly and can even cause seizures or dangerously high body temperatures.

Coco's situation was a little different because her low calcium was discovered before her puppies were delivered. Her medical record describes her condition as hypocalcemia during prolonged early labor, while the veterinary team also warned us that she remained at risk for eclampsia while nursing.

Before discharge, Coco received additional IV calcium. Her ionized calcium eventually increased to 1.31 mmol/L, back within the clinic's reference range. She was sent home with oral calcium supplementation and instructions to continue it while the puppies were nursing.

Recovery Has Looked a Little Different

Coco has been recovering well from her surgery, although her milk production hasn't been as strong as I would like.

Interestingly, the emergency veterinarian told me that her low calcium might also have contributed to her mammary glands not appearing very full immediately after delivery.

Fortunately, raising dogs in our home gave us an unusual advantage.

We had another mother nursing puppies at the same time, and she has done an amazing job helping supplement Coco's litter.

Coco can recover without having six puppies completely dependent on her, while the puppies still have access to a nursing mother.

What This Experience Taught Me

One of the difficult parts of breeding is learning that two pregnancies can look completely different.

I had seen dogs shake before delivering puppies, so when Coco started trembling, I initially interpreted it through the experiences I had already had.

For a while, everything still looked enough like early labor that I expected a puppy at any moment.

What changed my mind wasn't one dramatic symptom. It was that the expected next step never happened.

She kept shaking.

She wasn't pushing.

No puppy arrived.

And she was becoming tired.

That was when I knew I wanted a veterinarian to look at her.

I'm very glad I did.

Six little girls came home with us that day, Coco is recovering, and she is officially retired from breeding.

And Spirit, the puppy the veterinary team worked so hard to revive, is still here reminding me why sometimes the most important part of breeding isn't knowing exactly what's happening.

It's recognizing when something doesn't feel right and asking for help.