Infections and diseases that are of particular risk to pregnant dogs

Infections and diseases that are of particular risk to pregnant dogs

Health & Safety

If you breed from your dog, it is of course important to make sure that you do everything that you can to make sure that both the dam and subsequent puppies will be well and healthy. This means starting with a healthy, fit bitch that is in excellent condition and is also an excellent example of the breed, and so, will improve the breed’s stock as a whole-and ensuring that the owner of the sire does the same!

However, even when everything looks good on paper, there are a range of illnesses and infectious conditions that can pose a particular risk to pregnant bitches, and their subsequent puppies. Some such conditions are opportunistic and take a hold in the body because the bitch will of course be growing and developing and supporting her pups and so, her immune system will already be working harder than normal. Others may be caught as part of the breeding process itself, due to coming into contact with a strange dog-or, because as is often overlooked, dogs can and do carry and pass on sexually transmitted infections.

If you intend to breed from your bitch or if they are already pregnant, it is important to be aware of the most common problems of this type, including how they can be caught and how they can be prevented. In this article, we will look at some of the most common infections and diseases that are of particular risk to pregnant dogs. Read on to learn more.

Canine herpesvirus

Herpesvirus is a condition that many people are already aware of because it is commonly affects people as well as dogs, and is the condition responsible for things like cold sores, depending on the various different strains that exist. Canine herpesvirus is not contagious between dogs and humans, but it is very contagious between dogs, and is commonly passed between breeding pairs by means of mating.

If the bitch catches the virus during mating, there is a chance that the virus will lead to an early-stage miscarriage of the litter. Pre-breeding testing for both bitch and dog can be performed in order to prevent this.

Canine brucellosis

Canine brucellosis is a bacterial condition that once again, is a canine sexually transmitted infection, and one that should be tested for prior to breeding. The condition presents with virtually no symptoms in most cases and the bitch may appear well and the pregnancy proceeding normally-however, canine brucellosis can lead to late-stage miscarriage, or stillborn pups.

General infections contracted via mating

Mating two dog does of course lead to an exchange of bodily fluids, which is how conditions such as brucellosis and canine herpesvirus can spread-but there are also a wide range of other bacterial and viral infections that can be passed from dog to dog by mating too. Some of these can be avoided by means of ensuring that both dogs have received all of their vaccinations well in advance of mating-although this does not cover every potential eventuality.

Bacterial or viral loads that do not affect the sire may affect the dam because her body has not been exposed to them before, so it is really important to stay alert to signs of potential illness throughout the pregnancy and not overlook apparently minor symptoms.


Mycoplasmosis is caused be a type of bacteria called mycoplasma, which can be sexually transmitted or present at low levels within the bitch’s body prior to breeding. Again, pregnancy and all of its related changes can lead to the bitch becoming vulnerable to disease and so, permitting the condition to develop during pregnancy, while it may not have affected the bitch otherwise.

Mycoplasmosis can cause premature delivery which may mean that the litter is not viable and will not survive, or miscarriage and/or in-utero death of the litter and resorption during the earlier stages of the pregnancy. It can also lead to smaller than otherwise litter sizes when the litter is carried to term and delivered successfully.


Toxoplasmosis is something that most of us are peripherally aware of as a potential threat to pregnant women, and as such, those with cats that have to handle a litter tray are advised to take special care and wear gloves and wash their hands carefully to avoid contracting the condition.

Toxoplasmosis is a parasitic infection that can be passed on through improperly cooked or stored meat-raising the risk for bitches fed the BARF or raw meaty bones diet, as well as sometimes being present as a parasitic load in faeces, hence the cat litter risk.

Toxoplasmosis can cause miscarriage in the early stages of gestation particularly, and potential birth defects in litters carried to term. If you have a cat as well as your dog, keeping their litter tray well out of the dog’s reach, and ensuring that the dog does not scavenge or get given raw meat scraps will help to reduce the risks.

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