Canine Herpes Virus (CHV1)

There are a lot of different herpes viruses. You know about the ones that affect humans: herpes simplex and the others that cause chickenpox, shingles, and mononucleosis. There is also canine herpes virus (CHV1) which affects only dogs. 

Burrinjuck Labradoodles have been breeding dogs for over 15 years and I did not know about this virus in dogs and the deadly consequences for newborn puppies, until recently.  I would like to share this information to assist other breeders and also to inform our puppy owners of the new steps that Burrinjuck labradoodles will be taking to prevent another occurrence of CHV in our vulnerable Mum’s to be and young puppies. 

Celebration of a healthy litter

Coach and Sebastian's Litter

Birth Date 21/06/21

Imagine the excitement in our home with the birth of eleven healthy puppies born to Coach and Sebastian. This was a prize litter from Coach’s first joining. I had bred Coach myself from imported semen from the Yukon, BC with the handsome ArborGate Zeus.  Coach spent the first week adjusting to new parenthood in the warmth and comfort of our living room. At almost one week of age, the puppies were starting to roll off the cushion and we felt it was time to transition her out to the whelping box in the garage.  Not long after that, Hamish and I headed down to Melbourne as I had enrolled in a St Johns First Aid Course. We arranged for our regular helper, Belinda to house-sit for us and look after the dogs and puppies.

When it started to go wrong

It was our second night away that we started to receive the phone calls. Poor Belinda!! 

Puppies were approximately 10 days of age. The first phone call, it was assumed that Coach must have squashed a puppy, as it was one of the bigger chocolate boys. Strangely, Belinda reported that the little creme boy was very wet and looked malnourished and she was not sure if he would make it through the night. I was surprised to hear Belinda give this feedback as both the creme boys had been the heaviest and largest puppies in the litter when we left.

The next morning, as expected, the little creme boy had died but the panic really set in, when Belinda reported that three more puppies had died by the afternoon.  We struggled to make sense of possible causes. Was Coach squashing them? Had she run out of milk? Were they too cold? Were they being neglected?  We locked Coach into the whelping box in the vain hope that she might be forced to care for them.

We arrived home later that evening, and as soon as I entered the garage, I knew it was viral.  The puppies were saturated from Coach earnestly licking them. They had diarrhoea and I witnessed one of the puppies vomit up some milk curd. The bedding was damp despite being regularly changed by Belinda.  The whelping box had a certain stench about it that made me want to dryreche. 

The remaining five puppies

 Still the remaining 5 puppies looked healthy and strong and had little round bellies so I hoped that the worst was behind us. You can see in the photo below, the size of the remaining creme boy. Unsuspectingly, he was the next puppy to pass away. The little girl in the left hand corner who was struggling with diarrhoea and had also stopped feeding was next in line. 

 We moved the pups back into the living room. We then spent the next 24 hours in a nightmare situation where one after another 3 more puppies gradually faded away. The first sign was that they lost their suckle reflex. They would begin to cry out in pain, for hours and hours without ceasing and their abdomens were distended. They were cold to touch and limp with no energy. The diarrhea and vomiting were not obvious features as mum was so fastidious about cleaning  but it definitely had a stench to it.  In the morning, we had 5 seemingly healthy puppies. By nightfall, three had passed away and the remaining girl was starting to show the same signs as her siblings. She had also developed conjunctivitis.  I was feeding this little girl with formula and miraculously she was sucking from the teat.  I really did think she was going to die too.

Then there were two.

I must confess, I rang our vet with the intention to ask her for euthanasia of our last remaining girl. I could not bear to watch the pain. I also discussed with her the cutting edge intervention of injecting the little boy with blood serum from Mum to provide some antibodies in the hope of assisting his immunity.  Bek agreed to see the two remaining puppies and assess the situation. We drove up to Porepunkah.  Bek was surprised by the spunk in our little girl.  She growled at our vet when injected with the serum and cried out in pain at the other interventions; antibiotics, multivitamins, and eye cream for the conjunctivitis.This baby had a will to live and a stubborn streak that would be her asset.  

The turning point

I believe it was the fresh blood serum that was extracted from Mum and injected into the puppies bellies that was the difference between life and death.  My own morale had been boosted with the kind words from our vet that I was doing a great job, so I continued with the bottle feeding and added some honey into the mix for good measure.  Then the miracle occurred. I put her back with Coach to keep warm and she started to muzzle around for a teat. For the first time in two days she began to nurse again from Coach.  I knew then that we had turned a corner.  The little boy is another miracle. Despite being surrounded by his entire siblings coming down with the virus he did not ever stop nursing and continued to thrive. 

The puppies at 4 weeks of age

The literature is bleak when it comes to survival rates from CHV. Surviving puppies are likely to have neurological deficits and ocular blindness. Sachi [Japanese for Miracle/Blissful Happiness] and Asher [Hebrew for fortunate/blessed] are doing amazingly well.  Both Coach and Sachi have a bit of a lingering cough but apart from this, both puppies are meeting their developmental milestones and I am in awe of their strong character and sass.

The Post Mortem

The autopsy results for the deceased puppies came back negative for everything tested including Parvo Virus; Corona Virus; Brucellosis; Giardia; Campylobacter; Yersinia; Salmonella and worms.  There was a moderate amount of E-Coli detected in the faecal sample.  Initially the vet feed this information back to me as the cause of the deaths. E-Coli is a bacteria that is found within the gut of all dogs however certain strains are dangerous to the health of vulnerable animals.  On further discussion with the lab technician however, she verified that E-Coli was not attributed as the cause of death due to the fact that there was no destruction of the small intestine or the large intestine.

 Clinically there was some minor bruising on the kidney  noted by one veterinarian however the specialist could not find further evidence of damage to the kidney.

There are no typical lesions for canine herpesvirus infection in the renal tissue”

After further discussion with our vet regarding these baffling results, it became apparent that a blood test to rule out Canine Herpes Virus was not undertaken and in fact, is not something that is routinely tested. I find this surprising, given the evidence that this virus is the most common culprit for death of newborn litters.  

Given the overwhelming clinical symptoms of Canine Herpes Virus in both Coach and this litter of puppies, we have decided to assume that Canine Herpes Virus [CHV1] is the diagnosis.  In the future, we would request that bloods for CHV be taken and also other organs such as the liver and the lungs be examined to shed more light on the underlying cause.

What have we learnt through this experience

THE PREVALENCE OF CANINE HERPES VIRUS

Up to 90% of the canine population has been exposed to canine herpes virus and in healthy adult dogs, this virus is asymptomatic.  Adult dogs can carry the virus but not show signs.  I believe that Coach picked up the virus from contact with a 7 week old puppy that was sharing our lounge room during crate training. This little guy showed symptoms of a minor cough.   This virus is not able to be transmitted between humans and canines. It is not a problem in most situations …except for pregnant bitches and newborn puppies who do not have the antibodies or the ability to regulate their body temperature. 

BURRINJUCK WILL NOW QUARANTINE THEIR EXPECTANT MUMS FROM THREE WEEKS PRIOR TO BIRTH TO THREE WEEKS AFTER BIRTH.

 

THE IMPORTANCE OF KEEPING THE PUPPIES WARM

Newborn puppies are not able to regulate their body temperature. They are therefore not able to develop a fever to destroy viral cells before they take over.  Canine Herpes Virus does not survive well outside its host, it is easily killed with household cleaners and also warmth above 35*celsius. 

BURRINJUCK HAVE PURCHASED LARGE SIZE HEAT PADS FOR ALL THE WHELPING BOX AREAS. WE ARE ALSO SERIOUSLY CONSIDERING THE PURCHASE OF A HUMIDICRIB TO AID SICK PUPPIES IN THE FUTURE.

 

EARLY INTERVENTION IS KEY

I began to supplement feed Sachi prior to her completely losing her suckle reflex and kept her warm BEFORE she started to fade. I also think our vet was brilliant in her care of Sachi and Asher.  The blood serum was like a magic potion and the provision of antibiotics was also important to prevent a secondary bacterial infection while she was so weak.

IN THE FUTURE, I WOULD NOT HESITATE TO START THE PUPPIES ON FORMULA FEEDING PRIOR TO THEM SHOWING SIGNS OF SICKNESS. I WOULD SEPERATE THE PUPPIES OUT FROM EACH OTHER TO PREVENT THE HEALTHY ONES FROM PICKING UP THE VIRUS FROM THEIR SICK LITTER MATES AND I WOULD CONTACT MY VET AS SOON AS POSSIBLE TO RECEIVE SUPPLEMENTAL VETERINARY SUPPORT.

 

THE VIRUS CAN STILL SHED 

 In a similar way that most of us have had chicken pox or a cold sore (herpes), we go on to carry that virus with us throughout life. When we are under stress or our immune system becomes compromised,  that pesky cold sore might even show up again and again. Canine Herpes Virus functions in the same way.  Dogs may shed the virus from time to time, if they are also experiencing physical or emotional stress.  We may not even be aware of this shedding as mostly Canine Herpes Virus is asymptomatic in healthy adult dogs.

In the case of Coach and her two surviving puppies they are displaying very few signs of illness now however they will still be shedding the virus from nasal and oral secretions, in their urine and faeces and in Coach’s vaginal discharge. 

WE HAVE REQUESTED THAT OUR GUARDIAN FAMILIES KEEP THE NEWBORN LITTERS AT THEIR PLACE FOR THE TIME BEING AND WE WILL NOT BE BRINGING THEM HOME UNTIL THE DANGER PERIOD HAS PASSED, AFTER THREE WEEKS SINCE INFECTION.

Lets start the discussion

We look forward to answering any questions or comments in regards to this post.  I think it is important that  Burrinjuck is able share the knowledge that we have gained the hard way, to prevent these sort of tragedies happening in the future.