dimanche 13 août 2017

The purebred producer of Canadian horse

The purebred producer of Canadian horse
Introduction
Canadian horse is one of the most, if not the most, ancient breed of North America. They have been very useful in the construction of our country, the country of which they bear the name. They were the perfect little farm horse: enduring, strong and gentle. This may be the reason why their nickname is “the little iron horse”. But today, replaced by tractor and hydraulic machine, they lost their initial purpose. Some breeders are working hard to revitalize the breed and to make it popular again, starting by showing how good riding horses they are. Canadian horse is a small breed that is just starting to recover from being almost extinct. The subjects that will be looked at here are: History of the breed, registration book, phenotype, temperament, environmental impact on the breed, genetic disease and future of the breed.

Le noir Dynamo Kafka


History
Canadian horse is believed to be the first breed of horse in North American. In fact, it was the first studbook ever created in North America, in 1889 (Khanshour and al, 2014). According to some evidence, Canadian foundation horses were introduced to Canada by King Louis XIV around 1665 (lechevalcanadien.ca, 2008; Prystupa and al, 2012). There was no information left on the breeds sent to New France at this time. Recent research on DNA of multiple horse breeds, found that Canadian horse were closely related to draft horses, especially Percheron and Breton (Khanshour and al. 2014). Belgians and dales ponies were also closely related to Canadian. There were around 100 foundation horses from different breeds that were the base of the breed creation. They evolved in a rude climate in an isolated area and were bred with no influence of other breeds or blood lines (chevalcanadien.ca, 2008). By 1784, the breed counted around 30 000 individuals (Gendron, 1993). The combination of a massive export for war and the industrialization of the agriculture almost bring the breed to extinction (Oklahoma state university, 1998). The livestock of Canadian horses through the world was estimated to 5000 individuals in 2015 (Leprince, 2015). The breed is still recovering of the great lost they had back then. There are now breeders of Canadian horses outside the Canada; United States and France (clrc.ca, 2014; lechevalcanadien.ca).There is also Canadian horses that are sold to particulars in Europe (France, Germany and Swiss) and everywhere in the USA.
There is some evidence that Canadian horse was a foundation breed for many other North American breeds as: American Saddlebred, Standardbred, Northern plain mustang, but especially important in the development of the Morgan (Khanshour and al, 2014).


Registration Book
Canadian horse registration is a closed book separated in two categories: purebred and grade horses.
Purebred: Studs should be at least 96,9% purebred Canadian and mares should be at least 93,8% purebred (clrc.ca, ND).
Grade: Geldings of at least 75% Canadian (no studs are allowed) and mares that are between 75% and 93,7% purebred (clrc.ca ND).
To be eligible for registration both foal parents should be registered, have a blood type certificate for the sire, have a parentage certificate and the name of the foal should begin by the right letter (each year of birth has a letter) (clrc.ca, NhasD).
The registration name should always be: The breeders’ breeding name, the name of the sire and the name of the foal (beginning by the year letter). For example: Windigo Noireau Héritier, the horse came from the Windigo breeding facility, sired by Noireau and born in 1998. All of his future foals will also wear is name in the middle.

JP Casselman Wilfrid Dazzler, stallion


Phenotype
The breed standard is divided into 8 points; head, neck, shoulders, body, forequarters, hindquarters, legs and general exterior appearance (lechevalcanadien.ca, 2008).
Some important characteristics of the breed are (lechevalcanadien.ca, 2008; Oklahoma state university, 1998):
-Mane and tail: Abundant, long, dense and wavy
- Body:  Short and strong back, Medium sized neck large at its base, long muscled shoulders, deep chest, strong and muscled back end, slightly sloped croup.
-Legs: Strong, straight front legs, angulated hind legs, articulations well defined, short canon bones, strong large hoofs, thick and lean fetlock, medium sized and strong pasterns.
-Head: Short, straight lined and lean, short and thin ears, large and bright eyes, large nostrils, small lips, well-defined cheeks and flat forehead.
Stand from: 14 to 16 hands, but taller horses start to be seen.
Average weight: from 1000 to 1400 lbs
Colours, starting from the most common to the less common: Black, bay, chestnut, palomino, buckskin and grey. Blaze and white socks are also seen and accepted.

JP Casselman Wilfrid Dazzler, stallion


Temperament
Canadian horses are calm, intelligent and have a vivid personality. They are loyal and trusting companions with great reliability.

Environmental Impact on the Breed
The environment in which the Canadian horse had evolved had a big impact on the genetic of the breed. Indeed, with the long and hard winter of the Quebec Province, only the more rustic and the strongest could survive. Winter was really cold and feed were not as accessible as it is today, horses needed to live in extreme cold with minimal feeding requirements, or less. In time of extreme cold, digestible energy given to horse should be raised by 2,5% for each degree Celsius below -15°C (Cavanagh and Ternan, 2014). As such increase in feeding wasn’t really possible back then, horses that were good at storing fat easily (easy keeper) were the ones that had better chance to survive and to be useful. Horses that were insulin resistant were also advantaged in those climates (Treiber and al, 2006) because it is probably caused by a “thrifty” genotype (Kaczmarek and al, 2016). This was related to obesity, which gave them some “reserve” for the hard winter. Those horses that were more resistant and that passed through winter more easily were probably more fertile and were more “wanted” as breeding animals, because they were in better shape and ready to work for all winter.



Genetic Diseases
There is neither major genetic disease, nor breed specific disease identified in the Canadian horse breed. On the other hand, there are some genetic predispositions in the breed for developing some metabolic diseases. This means that those diseases are not breed specific, but some genetic factors in that breed can enhance the chance of developing them. This would be why some Canadian horse has more chance of developing those diseases than Arabian, for example.
Those metabolic diseases we talk about are: insulin resistance (IR), laminitis and Cushing's disease (CD). What was an amazing asset for survival back then is what can make them more prone to develop metabolic diseases today. Let me explain, it was hard to have good hay at winter back then, so horses that were good at storing fat were advantaged. Today, good quality hay is easily available at winter, so those horses are now easily obese, which can be detrimental to their health. In human, metabolic syndrome is now believed to be an inherited autosomal dominant trait. This may also be the case with horses, further research could be interesting. As we have seen in the environmental section, horses with easy keeper genetic and with IR were advantaged in survival. This may be why these problems are more encountered with Canadian breed.

Insulin resistance: Insulin resistance occurs when tissues become more resistant to insulin (they are less responsive to it), which make them absorb less glucose. Glucose will then be higher in the blood. Obesity is an important factor in the development of IR: obesity and IR are positively correlated (Treiber and al, 2006). IR is believed to be determined by a number of genetic factors (Kaczmarek and al, 2016) with an alimentary trigger: high carbohydrate diet, which exacerbates IR (Treiber and al, 2006).  So it is really important when you have a horse that has more chance to carry some thrifty genes to take extra care about his nutrition. Keep an eye on the quantity of food he receives, making sure to meet is nutritional requirements, but avoiding overfeeding (so obesity is avoided). As seen previously, Canadian horses are genetically closer to draft and pony breeds which means that they probably have more efficient and slower metabolism just like them (Cavanagh and Ternan, 2014). Looking at the minimal nutritional requirement from the National Research Council will be a good starting point to manage their food intake properly.

Laminitis: Laminitis is a major disease among equine population. Laminitis occurs when there is inflammation in the lamellar part of the foot. Blood flow is disrupted and lamellae start to necrosis and detach from the hoof wall. This removes support for the third phalange and causes it to flip. The exact mechanism is not 100% known but there are some suspicions of a major gene or genes expressed dominantly (Treiber and al, 2006) that could explain why two obese horses, fed the same thing and housed in the same environment will not both develop laminitis. Again, thrifty genes could be a part of the problem. Like with IR, nutrition is really important, but also trimming: making sure to avoid running heels and long toe kind of foot (Loving, 2009). So treatment for this disease consists in making sure to have good feeding management and taking care of the hoof properly. In other words, balanced diet and balanced feet (short toes, balanced trimming).



Cushing's disease: Equine pituitary pars intermedia dysfunction (Cushing's disease) is a progressive endocrine disease that often starts with older horses (McFarlane, 2007). It is in fact a dysfunction of the pituitary gland that changes the secretion of ACTH hormones and cortisol (The Pituitary Foundation, 2015), causing some change in horses’ metabolism. Cushing's disease is believed to be a genetic disease that has environmental triggers (McFarlane, 2007). Every horse can develop CD, but some breeds are at greater risk. Again taking care of the nutritional side is really important, but putting an extra care on the healthiness of the environment and keeping a balanced trim are also important in the management of CD. The drug pergolide is also often used to keep CD under control (petmd.com, ND).
So in summary, those diseases are not 100% caused by one thing, it may be a dominant gene or a combination of genes that are influenced by the environment of the horse and by his nutritional management.


Future of the Breed
The breed may be small, but it has a really great genetic diversity, which means they are still a viable breed, with a really low inbreeding index (Khanshour and al, 2014). This is a good indicator of the genetic health of the breed. Moreover, they carry some rare alleles (Khanshour, 2014), which make them even more interesting, genetically speaking.
The Canadian horse is a big part of our history, an important pillar in the development of our country. It would be so sad to lose such a big part of our heritage. They have been recognized as part of the heritage by Quebec government in 1999 and have become the national breed in 2002 (lechevalcanadien.ca, 2008). Despite these facts, government is inactive in the saving of the breed. They do not actively do something to help concretely the breeders or the breed. It is too bad they don’t help preserve this national treasure.
With the agricultural revolution and the rural exodus, breed that was used in the past for agricultural work lost their popularity. Canadian horses may have similarities with draft breeds but they are physically different. They are lighter which make them more suitable for riding. Let’s be honest, they may not be a grand prix breed, or a race champion breed, but these horses are the all-around horses by excellence. They are perfect for the rider that wants to have fun and try a bit of everything. They are enduring, strong and reliable horses. A study of equine Canada showed that 75% of adult equestrian were pleasure riders (equestrian.ca, 2011), which means that 75% of the equestrian should have a lot of fun owning a Canadian. Despite the fact that they are not grand prix horses, they can be competitive against other breeds, especially in dressage. They are seen more often in the show ring and they are not so disadvantaged by their rustic physic.

Canadream Kelbeck you and me (aka toque) at Devon horse show


Some breeders try to go in that way: breeding Canadian horses that are a bit lighter and taller than their predecessor. This is made in an attempt to make them a bit more sportive, so they will be a bit more competitive. Playing with the phenotype of a breed needs to be done carefully. One reason is because we don’t want to denature the breed in a way that the breed doesn’t look the same anymore. A second reason is that changing a phenotype need to be done by breeding horses that are phenotypically similar (Equine Genetics Workbook, 2013). This needs to be done the right way, because if not, it can lead to inbreeding. Inbreeding can be good if done properly (horses free of genetic diseases, avoid pushing the inbreeding too far, etc.), but as the breed as a really low inbreeding coefficient and a great genetic variety it would be sad to lose that. Breeders make incredible efforts to revitalize the breed and to make them popular again. Breeding horse is not easy, especially with rustic breeds because people are more attracted by tall, delicate and shiny sports horses. But there are still passionate peoples out there that try to save the breed.

Canadream Alex Shining Star on the cross country course

This breed deserves saving, for their part in our history, but also because they really are good horses that have a lot to offer. It is a healthy breed, with a lot of genetic diversity. Canada should start to be proud of their national breed and start to rediscover them.

Conclusion
In conclusion, the Canadian horse is a little national treasure. It is a breed that has a great part in the history and construction of the Canada. Canadian horses have been great partner to all farmers trying to survive in the New France, helping them in their daily lives. Losing that heritage would be a shame. Especially knowing that the breed is so healthy, genetically and physically speaking. They may have a genetic predisposition to some metabolic diseases, but a proper management of their nutrition and their environment should really help reduce the chance of developing these problems. Knowing that the breed is at risk due to their thrifty genes will leave a chance to their owner to start a good management routine right at the start. This should not stop someone from buying a Canadian horse, every breed has their little or big genetic problems. The Canadian horse has a lot to offer for their future owners, capable of offering them a lot of pleasure in multiple disciplines and able to compete at a good level, especially in dressage.
We should never forget this adage: We raise for our children the horse of our fathers.

Canadream Kelbeck Belle-de-mai


Bibliography
Article
Anas Khanshour, Rytis Juras, Rick Blackburn, E. Gus Cothran, 2015, The Legend of the Canadian Horse: Genetic Diversity and Breed Origin, Journal of Heredity 2015:106(1):37–44

Dianne McFarlane, 2007, Advantages and limitations of the equine disease, pituitary pars intermedia dysfunction as a model of spontaneous dopaminergic neurodegenerative disease, Elsevier

Jaclyn Mercedes Prystupa, Pamela Hind, E. Gus Cothran, Yves Plante, 2012, Maternal Lineages in Native Canadian Equine Populations and Their Relationship to the Nordic and Mountain and Moorland Pony Breeds, Journal of Heredity, 2012:103(3):380–390

Katarzyna Kaczmarek, Bogdan Janicki, Maria Głowska, 2016, Insulin resistance in the horse: a review, Journal of Applied Animal Reasearch, Vol. 44; NO. 1, 424–430

Kibby H. Treiber, David S. Kronfeld, Tanja M. Hess, Bridgett M. Byrd, Rebecca K. Splan, W. Burton Staniar, 2006, Evaluation of genetic and metabolic predispositions and nutritional risk factors for pasture-associated laminitis in ponies, Scientific Reports: Original Study, Vol 228; NO 10, P. 1538-1545

Book
Cavanagh and Ternan, 2014, From the horses’ mouth nutrition, feed and feeding, matrix multimedia
S.Loving, Nancy, DVM, 2009, Nouveau manuel vétérinaire pour propriétaire de chevaux, edition vigot, translated from English by Patrick Morin, DVM, originial version : All horse system go, 2006
Website
Canadian livestock record corporation, no date, Horses Eligible for Registration
Canadian livestock record corporation, 2014, Members Listed by Province
Equine Canada, 2010, People in The Industry in 2010

Leprince, Jean-Michel, 2015, Le cheval canadien va-t-il disparaître?

Pet MD, 1999-2017, Cushing ’s Syndrome in Horses
The Canadian horse breeders association, 2008, Breed Info
The Canadian horse breeders association, 2008, List of Member
The Oklahoma State University, 1998, Breeds of Livestock - Canadian Horse
The pituitary foundation, What is the pituitary gland?, 2015



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