Having urban chickens infected with Marek’s disease: when your passion turns into a nightmare


Written by Benoit G. and Louise Arbour

I’m a business and sales guy. My wife works as a nurse. My wife and I don’t have children, but the idea of having chickens in our yard has been on my mind for a long time. We love animals and I am a bird and photo enthusiast. I am passionate about life, I like to get to the bottom of things.

My story about the hens began a few years ago on Ricardo Le Fermier urbain’s show, around 2014, which made me want to have hens in order to have fresh eggs. A few years go by and on May 1st, 2016, I decide to go for it.

After reading two books and taking a small course in the Laval region on chicken breeding, I discover that there are hundreds of breeds of hens, each with their own characteristics. In my quest, I am told that there are two options available to me. The first one is to go to an agricultural coop and get red or common mature hens ready for laying for the modest sum of 15$ (vaccinated hens, dewormed, etc.). The second option is to buy chicks and raise them to maturity.  Leafing through a book on chicken breeds, I tell myself that if I’m going to start this adventure, I might as well have beautiful chickens! 

I then start looking for hens of different breeds and I quickly make my choice on the Chantecler Blanche and the Wyandotte Argentée which are two breeds very well adapted to the Quebec climate, important details, because I want to keep them all year round. As for the hen house, I find a mini urban hen house for 3 to 6 hens, and, without knowing that this starting hen house did not correspond at all to the needs of my hens. So I had to completely modify it, isolate it, increase it, double it, in short… if I had known, I would have done differently. Woe betide me about all my research and the beginning of this adventure, because I was not given a clear explanation of the ins and outs of the hens breeds and the differences with the vaccines. 

I join Facebook groups later that will reveal horrors about the health of hens and various diseases. Because I was trusting and new to the field, I had no perspective and no reason to worry about the risks and dangers that lay ahead of me with the naive choices I made. 

I quickly learned in my research that in Montreal hens are illegal despite the fact that there were pilot projects in two boroughs. But to hell with the bylaws, I learn that many citizens are illegal in several cities across the province. All I have to do is make sure that my neighborhood agrees. Surprised, my neighbourhood is happy with this initiative. Go, I’m going for it.

Thanks to my research on the internet, I find a “small chicken breeder” who owns the 2 breeds of hens I want. On May 1, 2016, I go to pick up my 11 chicks from the producer. You’re going to say 11 chicks !! Yes, natural selection obliges, because I will probably have some roosters and not just hens on this number … and roosters in town it’s not a good idea and moreover it doesn’t lay ! After thinking about it I say to myself: I will have at least 3-4 hens left to lay eggs and I will give the remaining roosters.

After a week, one of my chicks died, then a second one. My search for answers on these deaths will begin after the fourth death three weeks later at the Saint-Hyacinthe Veterinary Hospital. The third one seems to have died from E-Coli, but with the lack of flesh on the bird, the tests are not conclusive.

It was around this time that I met Louise Arbour from Poules en Ville and enrolled in her training in Terrebonne. She makes me understand that my choices regarding unvaccinated chickens were made to our great sorrow and suffering to see all our chickens die one after the other and I spare you the sadness and all the mental burden that it caused my girlfriend and me. The cost of having one of them euthanized and to document and accompany them in their last breath. I would like to thank these really fantastic veterinarians from the Laval clinic, Dr. Maccolini and Dr. Hébert, they are so good at taking care of urban hens. On that note, I call Louise Arbour several times for advice. The chickens are falling in battle due to au Marek, a level 4 contagious disease…so contagious that if it were transmissible to humans, we would have to protect ourselves as if it were Ebola, SARS, COVID… it’s in the air everywhere! Excreted by feather dust.

You have to understand that our chickens all had names and were treated like pets. The anger against this breeder who was aware of the disease in his farm made me question his ethics. 


After more than 1300$ spent in veterinary care and food, not counting the coop expenses, I find myself in a dead end. On one side, there is the laying hen industry, the MAPAQ, the Food Inspection Agency and on the other side, the small producers and simple citizens. It’s not easy to find your way around. 

You want vaccinated hens, you have only one choice, the red, black, Colombian, white hens, those coming from large hatcheries. 

What is Marek’s disease? Well read these links, one in French and the other in English which is more complete, before continuing your reading, because you will have difficulty following… Then, it is not only Marek’s disease that you have to be wary of… see the list on the Avia Quebec link….


As you have read, my coop and my remaining hens (1 as of April 10, 2017), are carriers of the disease and my yard soil and coop are contaminated for the next 5 to 7 years.

After more than 1300$ spent in veterinary care and food, not counting the henhouse, I find myself in a dead end. On one side, there is the laying hen industry, the MAPAQ, the Food Inspection Agency and on the other side: the small producers and simple citizens. It’s not easy to find your way around. 

You want vaccinated hens, you have only one choice, the red, black, Colombian, white hens, those coming from large hatcheries.

My beautiful and healthy ISA red chickens!

For all purebred hens from small producers and good luck finding vaccinated ones. Small-scale breeders of purebred hens often mistakenly think that they do not have access to vaccines. This is not true. By working with their veterinarian, they can set up a vaccination protocol and learn the methodologies and practice. They order the vaccines from the veterinarian who orders them from suppliers such as Tripple V for example. https://www.triple-v.ca/ .


See the example of Ms. Anik Bertrand in Abitibi. She is so convinced that she has created a site with all the information to encourage all farmers to follow her example. https://auniddepoule.com/. 

MAPAQ does not offer services or follow-up with small producers or citizens affected by this disease. We are left to our own devices. MAPAQ and several veterinarians believe that the majority of small farms in Quebec are carriers of the disease, which is not reassuring.

Knowing that producers are selling sick hens is as distressing to me as puppy mills. Long live Quebec and small animals! My recourse, the Office de la Protection du Consommateur.

But after analysis, this recourse will not change anything, at least at my level, I still only had 9 hens and 2 roosters. My last hen died in autumn 2018. In the spring of 2017 I decided to acquire 3 vaccinated laying hens this time. In spite of this, it is still possible that the new ones will develop the disease according to the strain that was rather virulent. Of course one of them was struck by the disease in autumn 2018. More than 2 have survived for the moment.  One remains to this day. Having the Marek in your backyard is unmanageable when it comes to biosecurity… think about it: everyone who walks in my backyard, brings the virus with him everywhere he goes, and so would I, if I forgot to change my shoes and clothes.

Of course my story will make some people smile, especially the big producers who for them this disease can be devastating. Globally, this disease represents significant losses to the poultry industry every year. Vaccines are mandatory in the industry. A change in regulations and help from the avian pharmaceutical industry would be welcome as well, given the global movement on urban agriculture.

I would like to warmly thank veterinarians Dr. Julie Hébert and Dr. Édouard Maccolini for their professionalism, compassion and support.

A summary from a passionate person!


To learn more, get informed and take the right training. Louise Arbour of www.poulesenville.com now offers her complete training online! It’s a must: https://formation.poulesenville.com/ and she publishes a book at Ecosociété: Des poules dans ma cour.

Since the fall of 2020, a major mobile vaccination pilot project has been underway in Quebec. Thanks to committed veterinarians who want to innovate and make a difference in the world of urban hens and among breeders.  The goal is to be able to offer a mobile vaccination clinic that goes to breeders of purebred hens. The veterinarian ensures a good vaccination protocol. In addition, those who have small flocks of less than 5 chicks will be able to make an appointment to have them vaccinated at the clinic. This is a first in Quebec. In addition, a chicken breeder from the Abitibi region promotes vaccination through her website: Au nid de Poule and encourages all her fellow chicken and poultry breeders to follow in her footsteps. Mrs. Anik Bertrand is to be congratulated for her tenacity, her research and the quality of the information she provides on her site. https://auniddepoule.com/

Things are slowly getting better. We hope to see pharmaceutical companies offer products that are increasingly easier to handle. Of course, the collaboration and team spirit of veterinarians and breeders is at the heart of the success of this great company.

We hope to see all the clinics taking turns. With telemedicine, no matter where you are located, and if in your area no veterinarian treats chickens, at least one veterinarian will be able to offer you a consultation and even send prescriptions to the clinic closest to you. The clinics will be able to have the products you need on hand. 


livre couverture

Des Poules dans ma cour

availalbe at .https://www.leslibraires.ca

The happiness of healthy chickens

At the very least, visit their website and take the time to prepare yourself before you start. This is the best advice I can give you. Since that time, some breeders are starting to vaccinate their hens and I hope that in the future, we will have more and more opportunities to have all these beautiful vaccinated hens in our yards.



Pathogen: Marek’s disease is a disease that occurs worldwide. All herds, except those kept under particularly strict conditions, are presumed to be infected. Modes of transmission The disease is highly contagious and the incubation period can last several weeks. The virus develops inside the hair follicles of diseased birds: when the feathers fall off, the virus finds its way into the environment where it can survive for months.

Other birds inhale particles of the virus from litter or dust and become infected in turn. Infected birds become carriers for the rest of their lives and shed the virus for long periods of time. Transmission occurs only horizontally, not vertically.

Photo: Sciatic paralysis. poultrymatters.com Clinical signs The disease is not always apparent: the severity of clinical signs depends on the virulence and dose of virus, the age of the birds, passive immunity and several environmental factors. On the other hand, it can cause a decrease in production and growth, resulting in significant economic losses. Possible characteristic clinical signs include: – Sciatic nerve paralysis – Atherosclerosis – Bird becomes blind and eyes turn blue – Depression and cachexia followed by death Diagnostic procedures – Necropsy: larger peripheral nerves and lymphoid tumors in different organs (volume enlarged organs with white nodules) without affecting the Fabricius bursa (characteristic) – PCR – Histology/immunohistochemistry Photo: multifocal white nodules on the liver. Yves Robinson.


No treatment exists for Marek’s disease. We therefore want to prevent infection, decrease the virulence of the strains and improve immunity. Vaccination is the main method of control. The vaccine is administered at 18 days incubation, in the egg at the time of transfer or subcutaneously at 1 day of age at the hatchery. Immunity takes 7 to 10 days to develop: exposure should be minimized until then. After that, it is a lifetime immunity. – Biosecurity measures to prevent spread between flocks and between lots – Separate birds by age groups – Avoid multi-ageing – Wash, disinfect and vacuum the buildings – Do not use litter from previous lots – Ensure good ventilation and establish positive pressure inside the buildings.



Biosecurity measures to be favoured.

Effects of biosecurity measures and explanations

References Avoid mixing herds of different ages.

Promote the rearing of caged laying hens

Favour ≤ 3 birds per cage The study shows that the risk of Marek’s disease is reduced by 90% and mortality by 30% in flocks of birds of the same age compared to multi-age farms.

The chances of Marek’s disease increase by 4.3 when birds are raised on the ground compared to birds raised in cages. The chance of Marek’s disease increases by 3.7 when there are more than 3 birds per cage compared to 1.2 or 3 birds.

Heier & Jarp. [1999]. Study of laying flocks in Norway References: 1. Boulianne, M. and J. P. Vaillancourt (2011). Notes de cours. DMV 4133 –

Poultry medicine 2. Heier, B. T. and J. Jarp (2000). “Risk factors for Marek’s disease and mortality in white Leghorns in Norway. “Prev Vet Med 44(3-4): 153-165 3. Kahn, C. M., S. Line, et al (2010).

Marek’s disease. The Merck veterinary manual. Whitehouse Station, N.J., Merck & Co.: 2449

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The book "Des poules dans ma cour"

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Caroline Tremblay
Caroline Tremblay
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Such a good book! Bravo for all the reasearch! 🙂
Nancy Studer
Nancy Studer
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Like me, you've had chickens for a few years and you think that online training or books are not for you? Think again! You quickly realize the quality of the information and how much research has been done in order to be able to create such complete tools. It's never too late to learn and modify, even a little, our practices in order to offer even better to our chickens. Don't like to read? Give yourself the gift of online training, or you'll love the book that reads itself!Congratulations! For me, you are THE reference person!
Mylène Ferron
Mylène Ferron
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I took the online training (webinar) offered by Urban Chicken Coops because I had the idea of building an urban chicken coop this summer. I didn't know anything about chickens or coops, and the information I found online was often contradictory. Until I found the Urban Chicken Coops website! The training offered is complete (very) and Ms. Arbour transmits her knowledge in a simple and understandable way for everyone. I highly recommend her!
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