mercredi 6 décembre 2017

Obesity of the modern horse: a review

Obesity of the modern horse: a review

Introduction:

In the developed country of today, horses, just like peoples, tend to be more obese than before. Horses are not used to work long hours to plow the land or to transport the family from point A to point B. Today, they are more companion’s animal just like dogs and cats, except for the fact that they can’t sleep on the bed. Some are still used in a business purpose like  with some competition animals, but most of the horses are now leisure horses. This mixed with the fact that today’s horses are not in the same precarious environment as their ancestor has created a new problem for them: obesity. More and more horse today are kept on light to moderate exercise and have access to really good feed all year long, even in winter. They are now companion animal, that their owner loves so much, they are well cared for and even sometimes, maybe too well cared for. It is important to understand this problem because it can have a great impact on horses’ health. To understand the problem, we must know every part of it. First of all, it is important to know what exactly is the definition of an obese horse and how to assess his body condition. Then, it is important to know what can cause obesity, what the consequences of this problem are and how to manage it. The last point is really important especially because bad weight lost program can have severe consequences. It is also important to know what a healthy weight is and what to do after the healthy weight is achieved. All those facts will help to understand and manage obesity, in an attempt to avoid or to reduce the prevalence of this serious problem among the horses' population.

What Is Obesity and How to Access It

To be sure that everybody starts at the same point, let’s look at basics. Horse owners often assess their horse's body condition wrong, thinking that fleshy horses are the normal healthy weight and often saying that their clearly obese horses are just a bit fleshy. So it is really important to learn how to objectively assess their horses’ weight.
 By definition obese is: very fat; corpulent (Canadian Oxford Dictionary, 2014). An obese horse will have big fat deposits all over his body. There are many ways to assess the condition of a horse’s fatness: body condition scoring, cresty neck scoring and weight formula. For a more accurate result, all of the tools discussed above can be used at the same time to monitor the weight and fatness of a horse.

Body Condition Scoring

The body condition scoring (BCS) is probably the most used tool to assess a horse's body condition, be it for poor or for obese body condition. There are two charts: the 9 points score and the 5 points score (Cavanagh and Turnan, 2014). The most used one is the Henneke et al. (1983) chart that classifies horses within 9 categories: poor, very thin, thin, moderately thin, moderate, moderately fleshy, fleshy, fat and extremely fat (NRC, 2015). For more detail refer to the figure 1 below.

Figure 1 body scoring charts of Henneke et al. 1983
To assess body scoring, 6 points of the horse body are observed and palpated by the observer: neck, withers, loins, tailhead, ribs and shoulder (see figure 2 below). Those regions are called fat pads and are the one where fat build up the most (Cavanagh and Ternan, 2014).

Figure 2: the 6 points of fat deposits source:http://hher.webs.com/neglectstarvation.htm
Observer should be careful to look only at fat pads and does not mix up with muscle (Cavanagh and Ternan, 2014), as some breeds have really big muscle mass, but no fat over it.

Cresty Neck Scoring

The cresty neck scoring (CNS) is the assessment of the fat deposit along the crest of the neck. This scoring chart is pretty new to the equine world. Some researchers have shown evidence of a correlation between high crest neck fat deposit and metabolic disequilibrium (Silva et al. 2015). BCS is a great tool to assess the obesity of the horse and CNS is a great tool to assess the risk of metabolic diseases (Silva et al. 2015, Frank, 2011). On the other hand, CNS should not be used alone, as some breeds or sex have facilities to build cresty neck even at a healthy weight. Neck crest fat deposit is also believed to be a long-term fat reserve that can be used when food is less available. Some evidence is showing that it can adapt following the seasonal metabolic rate change (Giles et al. 2015). So CNS is a really great tool that can help you to know which horse will need more monitoring for metabolic diseases, but for obesity assessment, it will be better to use it with the other methods.
CNS can be assessed as seen in the figure 3 below. CSN over 3 are the scores that need more monitoring, over that limit, there is an increased risk of laminitis (Giles et al. 2015) or metabolic syndromes.

Figure 3 CNS, Carter, et al. Chart, 2009

Weight Formula

This tool will not be as useful as the two above to assess if the horse is overweight or not, as like humans, horse will have different bone stature or height meaning that their healthy weight will be different from one to another. The weight estimation formula will be most useful for two really important points: Calculating the daily ration of a horse and keep a track of the evolution of the horse’s weight ( keeping a track of the weight loss or gain). 
There are two formulas used to assess the horse weight: heart girth + measure of the point of the shoulder to the point of the hip or heart girth + measure of the point of the shoulder to the most far point of the rump (Cavanagh and Ternan, 2014). Those formulas work for horses, ponies and draft breeds. Miniature horses have their own formula. Horses’ formula is available in both inches and centimetres but those in centimetres will be used here, as centimetres are more precise.

Figure 4 How to take mesurements
Horse formula (measure in cm):
Body weight (BW) in Kg +/- 10% =  ((heart girth)² * length to rump) / 11880 or ((heart girth)² * length to hip) / 8717
Miniature formula (measure in inches): BW in pounds +/- 5% = (9,36 x heart girth) + (5,10 x length) – 348,53
** These formulas are not accurate for foals and pregnant mares (Cavanagh and Ternan, 2014).
To keep a good track of the horse weight variation, make sure to always measure from the same points. That is to say don’t measure one day from the top of the withers and the next day just 1 inch of that spot, the variation in wither height (especially with high withered horses) will produce false results. They horse may have kept the same weight but the change in measurement spot will have changed the measures.

Causes of Obesity

Overfeeding

One of the most important causes of obesity is overfeeding. Overfeeding means: giving too much feed (often ad libidum) or giving feed that is too rich (energy-dense feed). Most of the horses today do not spend more or equal quantity of calories than they consume (Shea Porr and Crandell, 2008, Loving, 2009). When a horse eats more energy than he needs, the body will start to store the excess energy in the form of fat (NRC, 2015). People tend to give high energetic feed to horses (concentrates) and often they contain ingredients that are high in starch. Starch and sugary aliments are easy to digest by horses as they are made of non-structural carbohydrates that are easier to break down compared to complex one from hay (NRC, 2015). As they are such an easy access source of energy for horses, aliment that creates a high glycemic index like starchy aliments are often too rich for the majority of the leisure horses (Johnson et al. 2012). Moreover, horses today have access to lush pastures that are often so nutritive that it exceeds their needs in energy and proteins (NRC, 2015). They are in the pasture all day long and can eat as much as they want, which often result in obesity. Horses have originally evolved to graze and survive on poor pasture (Shea Porr and Crandell, 2008), this can explain why today’s horses that are kept on a really abundant and high quality hay/grass have so much obesity or laminitis problem.
Horses today have easy access to feed, often not a lot of space to move around (or almost nothing when looking to 24/7 stalled horses) and often live in hypo stimulating environments. This can lead horses to boredom. When they are bored, horses can eat way more than they need because it’s the only thing they have to do (Loving, 2009). When horses are housed in more stimulating environment they can spend more time doing other activities than eating (see how to manage the problem section for more information).

Lack of Exercise

Another really important contribution factor for prevalence of obesity today is that horses do not exercise enough. They have evolved to cover several kilometres per day while grazing or to find water or new safe area to eat (Shea Porr and Crandell, 2008). In nature, equids are always travelling around for a reason or another. Today, horses are often fed in feeders that are always at the same place, on a small area where food and water are close to each other, so they have no reason to move a lot. Some are kept on a stall all day long and get out for training or for turnout of four hours a day. They receive high quality feed and they are kept on stall or small paddocks that do not encourage them or give them the chance to make voluntary exercise (NRC, 2015). The majority of them are leisure horses that do not make “forced” exercise (riding or lunging) so often either.

Genetic

Some horses have a genetic predisposition to obesity. It’s not that there is a gene that makes them obese, it’s more about the way they evolve and the environment in which they evolve that make them more prone to obesity. Most of the breeds that are prone to obesity (ponies or horses) have often evolved in rigorous climate, where winter was harsh or were facing drought in summer. 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 in time, horses that were good at storing fat easily (easy keeper) were the ones that had better chance to survive and to be useful. The same could apply to horse confronted to drought: feed was less available and less nutritive. As mares with poor body condition (fewer than 5 BCS) have lower fertility rates and have fewer chances to carry a foal to term (Cavanagh and Ternan, 2014, NRC, 2015), easy keeper mares were those who had better chance to reproduce and to transmit their genetic material. This is probably why some breeds have such a tendency to obesity, the foundation mares that created the breed were probably a bunch of easy keepers.
Horses that were insulin resistant were also advantaged in those climates (Treiber et al., 2006) because the condition is probably caused or linked to some “thrifty” genotype (Kaczmarek et al., 2016). This was related to obesity, which gave them some “reserve” for the hard winter.
Just to give some example of this type of “easy keeper” prone to obesity breeds, let’s just think about the Canadian Horse, the Shetland pony or the Welsh pony.

Metabolic Syndrome

Metabolic syndrome could be placed in both cause and consequence of obesity. It’s a bit more like a vicious circle: Obese horses are more prone to metabolic syndrome and horses with metabolic syndrome have more difficulty losing weight (Loving, 2009). Obese horses are more prone to the equine metabolic syndrome (EMS) because adipose cells react to endocrine signals, the more we have adipose cells, the more the horse has a chance of hormonal irregularities (Loving, 2009). On the other hand, those horses have difficulty to lose weight because of a better metabolic efficiency (Frank, 2011), they tend to do more with less. That is to say that they tend to take better advantage of their food than “normal” horses (Frank, 2011) so even if they are fed less, they tend to stay overweight.
Equine metabolic syndrome is not a disease in itself, but a clinical syndrome associated with some diseases. In fact, it’s a set of risk factors that predispose the horse to other diseases (Frank, 2011).
Strange fat pads like the one in red, is one of the signs of EMS

Seasons

Seasons can affect horses prevalence of obesity. Why? Because back in time, horses had to make some energy reserves in the form of fat in anticipation of the winter. Indeed, as they had not always access to a good quantity or quality of food during winter, horses were programmed to make some reserve at the end of the summer (Loving, 2009). Fortunately, horses do not lack of feed during winter anymore, unfortunately their metabolism has not adapted to this fact yet (Loving 2009) making horses more prone to obesity at the end of summer (or early fall) and not losing this extra weight anymore during winter.

Consequence of Obesity

Insulin Resistance

Insulin resistance (IR) is probably one of the most important consequences of obesity. There is some evidence that IR can be promoted by obesity (Loving, 2009), but there is also some evidence that relates obesity to feeding carbohydrates rich food (Loving, 209). As obese horses often receive too much energy-dense food, both reasons can raise their chance of developing IR.
 IR is the reduced capacity of the body tissues to capture the glucose from the blood stream (Loving, 2009). Because the tissues become less responsive to insulin, the body then starts to increase the level of insulin secreted so the tissues will receive a stronger signal (Shea Porr and Crandell, 2008). So when tested, those horses will have increased levels of insulin in their blood. Stress can also raise the insulin level in the blood so it will be important to look with the veterinarian if the increased level of insulin in the blood is due to IR or to stress (if the horse needs to quit the barn to pass the tests for example).

Laminitis

Laminitis is also one of the most important and frequent result of obesity. It has been put under IR because it can be a prevalence factor of development on laminitis (Shea Porr and Crandell, 2008), EMS can also lead to laminitis (Loving, 2009), but at the end, it all comes the dominant factor for all those diseases: obesity. A direct link between obesity and laminitis is the fact that all that extra weight will overload the horses’ hoofs, which can create bruises and inflammation into them (Loving, 2009).
Laminitis is a general term which refers to an inflammation of the laminae of the equine hoof (Loving, 2009). In more advanced case, the third phalanx can detach from the hoof wall because of the too important laminae inflammation (the link between the phalanx and the hoof wall is weakened) and rotate. In worst case, the phalanx will rotate to such an extent that it will perforate the sole. So laminitis can be really painful for a horse and even life threatening.
Once laminitis is developed, it will be really important for the horse to lose weight as mechanical overload of the foot by excessive weight will aggravate the problem (Loving, 2009).

* An important point to note is that laminitis can have other factors that are not related to obesity (ex: retained placenta), even if they are less frequent, they are not impossible (Loving, 2009).

Development Orthopedic Disorder (DOD)

Obesity or overfeeding of the foal can have a really important part of the development of DOD (Loving, 2009). Overfeeding can also raise the chance of  DOD development even before a foal is born. Indeed, overfeeding of the dam can raise the chance of the foal to develop DOD (Loving, 2009). Obesity will put too much weight on the growing bones of the foal, causing them stress. DOD is a group of diseases which according to Cavanagh and Ternan (2014) include: physitis, osteochondrosis, OCD, wobbler’s syndrome and angular limb deformities.
Overfeeding will give so much energy to the foal that it will allow him to grow at a faster rate than a normal fed foal. Rapid growth rate will enhance the chance of a foal to develop DOD (Huntington, 2012, Cavanagh and Ternan, 2014). Moreover, obese foals often fail to become good athletes in the future (Huntington, 2012).  So it will be really important to resist the temptation to overfeed dams and foals. Seeing ribs is normal on a foal, people tend to think they are too thin but they are often just perfect. If we can see ribs but the foal has a great muscular mass on his body, he is not skinny. A new theory has emerged and found interesting correlations between DOD development and cartilage sensitivity to insulin (Huntington, 2012). This could give a new reason (not if there is a lack of it here) to avoid giving feed high in non-structural carbohydrates (concentrates) as those types of feed create a high insulin response due to an increased post-feeding glycemia.

Figure 5 Ribs are visible on this Canadian filly, but she has an adequate muscle mass and general body condition for a foal.

Stressed Joints

Stressed joints are a consequence of obesity as more body weight put more pressure on the articulation (Loving, 2009). It’s a simple physical fact, a weight-bearing surface will distribute the pressure evenly, when more weight is putted on that surface, the pressure will increase. So if an articulation needs to bear more weight it will receive more pressure. According to Loving (2009) the smooth and shiny articular surfaces degenerate when they are irritated by an overload. So the cartilage will be more and more damaged as the load increase (Loving, 2009).

Heat Stress

Obese horses are often intolerant to effort (Loving, 2009), they get tired more easily and have a less good cardiovascular health. An obese horse fat deposit is the reflection of an insufficient overall fitness (Loving, 2009).  When the horse will start a fitness training program, muscular mass will replace adiposity. 
As body fat is a great insulating, obese horses are more prone to heatstroke and hyperthermia (Loving , 2009, Tighe and Brown, 2004). Indeed, their abundant fat deposit will not dissipate the heat effectively. Moreover, the fact that they have to carry all that extra weight will require more energy from them and will be more tiring accentuating the need to dissipate heat (Shea Porr and Crandell, 2008).

Intestinal Lipoma

An intestinal lipoma is a fatty tumour which develops in fat (Loving, 2009) so an obese horse will have prevalence for developing this type of tumour. Horse over 15 years of age will have higher risks to develop a lipoma (Shea Porr and Crandell, 2008). Although this type of tumour is a benign one, there are still some health risks about it. This type of tumour often develops in the mesentery which supports the intestine. They then hang there and can easily move and flip in such a way that they can create a strangulation colic (Shea Porr and Crandell, 2008). There is no need to say that this is really dangerous, even deadly for a horse.

Parturition Problems

Obesity can lead to problems regarding breeding animals. Obese horses may encounter some irregularities regarding metabolic and endocrine regulation (NRC, 2015), which can play a role in reproduction. For stallions, it can even lead to infertility (Tighe and Brown, 2004). For obese mares it is the contrary, mares with BCS fewer than 5 will have more infertility or more difficulty to carry a foal to term than obese mare. The ideal weight for a broodmare is a BSC between 5 and 7 (Frape, 2010) but a mare that has a BCS over 8 will not be better nor worst broodmare than those between 5 and 7 (Frape, 2010). Cavanagh and Ternan (2014) for their part found that “In broodmare, obesity over 7 has been associated with prolonged luteal phases and lengthened interovulatory intervals so it can have an impact on reproductive performance”. So the opinion on that is still somewhat mixed.
Where there is a certainty of obesity causing problems to broodmare is with parturition. As seen previously, obese horses have intolerance to efforts. So when obese mares are foaling, they can be tired more easily (Frape, 2010) which can be life threatening for foals and for themselves.

Diabetes Miellitus

Diabetes Miellitus (DM) stands in the last place because of its rarity within the horse population, in contrary to humans where it is more common (Johnson et al. 2012). Although rare, it is still possible for a horse to develop this pathology.
DM is characterized by a really high glycemic index (hyperglycemia) that is caused by the horse not producing enough insulin or not producing it at all ( Johnson et al., 2012). The question is: Is the horse less prone to develop DM or is they die from mysterious cause at young age without anyone noticing the DM problem. Or maybe it is not present among equid population because back then, those horses died before they could reproduce so they never transmitted the genetic predisposition for the disease. It’s still a disease that has not been studied a lot.

How to Manage the Problem

Monitor Your Horse

This section comes first because the first step in a weight lost program is to keep a good track of the horse body condition all along the process. This will allow you to see if the horse is losing or gaining weight. When an owner sees his horse every day, the change in his body condition will be less noticeable as they change just a little bit every week.
Keeping an eye on the progress of the horse will also give the opportunity to adjust the nutrition of the horse in consequence of his weight lost. Some say that the quantity of feed that a horse should eat per day should be based on his healthy weight. But let’s look at the extremely obese horse, this could be a very drastic change for him. So keeping an eye on the weight lost of the horse could help the owner to adjust slowly the intake of the horse fallowing his weight. A slow and steady weight lost is preferable (Shea Porr and Crandell, 2008) as drastic weight lost can lead to some dangerous condition (see consequence of a bad weight lost program section below).
Application to keep track of the horse weight and BCS are available on smartphones. Some are even calculating the formula for weight, the user only has to enter the heart girth measurement and the shoulder to rump measurement. Then it offers a graphic version of the weight curve of the horse. So this can be a great option to keep a track of the progress of the horse.

Increase Exercise

The first rule for losing weight is that the horse needs to burn more energy than what he is consuming (Shea Porr and Crandell, 2008). Increasing exercise for an obese and unfit horse should always be progressive (Shea Porr and Crandell, 2008). Like in human, extremely obese horses need to go slow at the beginning because of their unfit system, starting with too much and too intense exercise could be dangerous for them. It could produce metabolic problems or heat stress to the horse (Shea Porr and Crandell, 2008). In the first few weeks, really obese horses should be trained in hand and exercised over 10 to 15 minutes of walk with few strides of trot (Cavanagh and Ternan, 2014, Shea Porr and Crandell, 2008). As the horse get fitter and slimmer, exercise can be increased. Owners should follow the rhythm of his horse and look for signs of fatigue. Owners should take a note that walking and trotting burn more energy than canter and gallop (Shea Porr and Crandell, 2008). It is recommended not to raise the intensity of the work before the horse BCS is closer to normal (5-6 BCS) (Cavanagh and Ternan, 2014).
It is interesting to know that moderate and regular exercise can help to prevent IR and laminitis (Frape, 2010) so irregular working program is not really good for horses. That is to say that working the horse regularly for two months then putting him in the field without any work for two other months and so is not a good idea. Metabolic rate change when exercise increase (Cavanagh and Ternan, 2014), so irregularity in an exercise program may cause metabolic problems.

Controlled Intake

Starting to calculate what a horse can eat is a great way to help him lose weight. There is some important rules to do so: no long fasting period, no fewer than 1,5% of the horse body weight (BW) in fibre and no feeding program that are below the NRC minimal feeding requirement.
Horses should not be fed under 1,5% of BW in fibre, fibre is really important for their digestive tract health (Cavanagh and Ternan, 2014). They have evolved to eat fibrous feed and to digest it in their hind gut. Some are losing weight with 1,75% of their BW in fibre and others with the NRC minimal requirement of 2% BW in hay. For some horses, only the fact that their portions are calculated is enough to make them lose weight.

 So to avoid not giving enough fibrous feed to horses, one can choose to give less energy-dense hay. When hay is harvested once mature, it contains less energy so the horse can eat enough hay without receiving too many calories (Cavanagh and Ternan, 2014, NRC, 2015). It is possible to add some chopped straw chaff with the hay so the horse will have a bit more to eat but not much more calories. Another option to reduce the energy density of hay is to soak it, so a good part of hydro-soluble carbohydrates will be removed from the hay (Cavanagh and Ternan, 2014, Loving, 2009). When this option is chosen, a good vitamins and minerals supplement should be given to make sure the horse has enough of them (this should be discussed with a veterinarian). Indeed, some vitamins and minerals are hydro soluble as well. To be sure the horses receive enough vitamins, minerals, proteins, etc. refers to the NRC minimal requirement. They should receive the minimal requirement for the entire categories, only the digestible energy (DE) can be reduced a bit (Shea Porr and Crandell, 2008, Loving, 2009).
Avoiding long fasting period is essential for the horse, because it will create boredom, stereotypies and because it is not good at all for their digestive tract that is made to receive a constant supply of food (Cavanagh and Ternan, 2014). In addition to the strategy of giving more hay that is less energy dense, some slow feeding strategies can be used. Using good quality hay nets can be a really interesting way to reduce the speed at which the horse eats his hay (Glunk et al., 2014) while making it more challenging, so it is a good mental occupation for the horse. Make sure to follow the company instruction on how to introduce the hay net to your horse. In addition to the hay net, feed multiple times a day will also help (Shea Porr and Crandell, 2008).

Reduce or Remove Concentrates

It will also be necessary to reduce to a minimum or even to avoid completely to feed concentrates to horses (NRC, 2015). If the horse receives a good quantity of it, reducing the amount over several days will be a good option. Most of horses do not need the extra energy and calories of concentrates (Shea Porr and Crandell, 2008). If there is any lack in the ration, vitamins and mineral supplements can be used. Note that ration balancer can be more caloric dense than people think, the supplement can be preferable to the balancer. If the hay is under 8% of protein, it can be balanced with a protein supplement that is low in non-structural carbohydrates (Cavanagh and Ternan, 2014).

Control Grazing

It is important to control the grazing of a horse to help him lose weight. As seen previously, pasture often exceeds DE requirement for horses. So overweight horse that has access to pasture will need some restricted grazing time or to wear a grazing muzzle to reduce the total food intake (NRC, 2015). It is important to know that the sugar levels of grass change during the day: the sugar level peak is in the middle afternoon and the lowest level is at the middle of the night (NRC, 2015). So it is safer for a fat horse to graze at night and to be removed from the pasture during the afternoon. Sugar level also changes during seasons: fructan is present at a higher level at spring and fall (Loving, 2009). This is because when the soil temperature gets lower sugar rise into the stems of the grass.
If removing the horse during the sugar peak periods is not possible, buying a grazing muzzle could be a good option to help reduce the intake of the horse while letting him graze constantly (Loving, 2009). A previous research from Longland et al. (2011) found that grazing muzzle reduced voluntary intake by 83% but a recent study from Glunk et al. (2014) found it was actually reducing it by 29% only. Maybe the quantity of voluntary intake with grazing muzzle can vary among individuals.

Environmental Enrichment

A new trend today is the use of what is called “paddock paradise” (PP) to enrich the environment of the modern equid. PP is a new way to conceive paddocks for horses. The starting point is to build a track instead of a square paddock and making a food station, a drinking station and a shelter station, all in different areas of the track. That way, horses are encouraged to move around the track to travel between stations. Instead of going from the hay to the water tub in a straight line, they need to follow the track. The track can also be built with different types of soil covering; it can be rocks or even safe logs that the horse needs to step over. These things can make the environment more interesting for the horse and can help him have other activities than eat all day long in addition to encourage movement.
Horses should also be offered the longest turnout possible with congeners. Walking is primary to their intestinal health because it fastens the intestinal motility. Congeners are also important for a lot of reasons but principally because horses are social animals that are happier when they can interact with other horses and also because being around other horses will encourage them to move more and play.
Some feeding toys can also be added, or simple toys like balls or even just plastic cane filled with rocks so horses can spend time exploring new things. Changing the toys regularly will help to keep interest of the horse. This can be a playful way to occupy horses’ time and to make a despooking activity at the same time.

Consequence of a Bad Weight Loss Program

Losing weight is important for the health of a horse, but doing it the wrong way can be as damaging or even more than keeping the horse obese. So it is important to know what needs to be avoided having a healthy weight lost program.

Worsen the Weight Gain

When an animal is fasted for several hours it will eat faster once given the opportunity to eat (Glunk et al. 2014). So fasting the horse for a long period and giving him free access to feed afterward can actually worsen the problem as he will eat his minimal DE requirement or even more in less time (Shea Porr and Crandell, 2008). Long fasting period can also alter the satiety signal of the horse; making him more prone to eat more than the amount he really needs (Loving, 2009).
So fasting is not the solution for a good weight lost. It’s better to give constant but slower access to feed.

Unbalanced Diet

Lysine and protein should never be given at a lower level than the NRC minimal requirement. Those two elements are really important to the horse, especially lysine. When reducing the DE available for the horse, owner should always make sure that other elements are available in the right amount (NRC, 2015). Hay should be analyzed and diet should be balanced with the right supplement if needed.
Unbalanced diet can lead to important deficiency that can be really detrimental even deadly to horses. Just to take some examples: Lysine is a really essential amino-acid, if the horse does not have the minimal requirement, it can impair the absorption of the other amino-acid, making the horse event more deficient (Canvanagh and Ternan, 2014). Deficiency in selenium as for him can have serious impact in cardiac functions (Cavanagh and Ternan, 2014). Indeed it can lead to impaired cardiac function and even pulmonary distress in severe deficiency. So a good balanced diet is really primary for a healthy weight lost program.

Hyperlipemia

Hyperlipemia happens when a horse lives in a negative energy balance for too long (Frape, 2010, NRC, 2015). In reaction to that, the liver will mobilize a high quantity of fat from the body and fat will accumulate into it (Frape, 2010, Johnson et al., 2012). Some equids seem to be more prone to develop this condition: horses and ponies that seem to carry “thrifty” genes (Johnson et al. 2012), mares especially in late gestation (compared to stallions and geldings) (NRC, 2015) and donkeys (NRC, 2015).
Hyperlipemia will be easily diagnosed by a blood test. Some evidence of the pathology will be visible to the naked eye as the serum will appear opaque with a light creamy colour (Dacre et al. 2003).  It treatment is difficult and there is a high mortality rate (60 to 80%) (Dacre et al. 2003) as it can lead to hepatic and renal failure (NRC, 2015).
This is why it is important to have a steady and SLOW weight lost, and to make sure not to reduce the intake too much.

What Is a Healthy Weight?

Healthy weight always depends on the horse bones stature and height. But BCS can be used to assess if the horse has reached is healthy body condition. For the general leisure horse BCS around 5 to 6 is really good. But depending on the horse’s purpose, the optimal BCS can change (NRC.,2015):
·         Broodmares will do better on a 5 to 7 BCS (NRC, 2015, Cavanagh and Ternan, 2014)
·         Foals are better to be kept on the thin side so around 4 to 5 BCS
·         Sports horses will do better around 5 BCS
In general, avoiding going into the extreme of the chart is a good idea, so stay around 4 to 7 BCS. Less or more are not healthy weight.

And After?

After the target weight is obtained, slowly increase the intake to reach a balance, where the horse is not gaining nor losing weight anymore. It will always need to be adjusted through the horse’s life depending on his activities or his metabolic rate.
If at some point horse need to have more energy (horses start to be trained to competition), fat and fibre feed can be more suitable for them as long as there is 6% fat or less (Shea Porr and Crandell, 2008). Oil is also a supplement that does not produce a high glycemic index.
After the weight lost, there is still work to do. Those easy keeper horses will always be easy to regain the weight they lost. There are some points to keep in mind:
·         Continue regular exercise, don’t stop and start training constantly
·         Once the horse is in a good shape and doesn’t need to lose weight anymore, slowly increase intake to see where is the line between losing and gaining weight and keep that balance
·         Keep a really slow rate of feed change (a longer time to change concentrates or hay or to go on grass)
·         Continue to keep sugar intake to a minimum, if some extra energy is needed, promote fat and fibre over starchy concentrates
·         Continue to monitor the horse weight and to balance the ration
·         Continue to make annual veterinary examination to keep a track on the general health of the horse as easy keepers are more prone to develop certain diseases.

Conclusion

There is no proven regiment to ensure weight lost in horse (NRC, 2015) some are easy to manage, some are easy to lose weight with a good program and others are almost impossible to lose weight. What is important is to slowly increase voluntary and forced exercises while reducing the caloric intake a bit. Always keeping in mind to follow the NRC minimal requirement for all other nutriments and to avoid extreme changes in exercise and intake. The metabolism of the horse has still not adapted to this new abundance of food and this lack of work, so it is up to the people around them to try to manage the problem the best they can. Avoiding obesity is important because managing the problem is way more complicated than it appears. There is still work to do to provide a better and healthier environment for modern horses, but people are working hard to improve it.






Bibliography

Books
Canadian Oxford Dictionary,2004, second edition, edited by Hatherine Barber, Oxford university press
Cavanagh and Ternan, 2014, From the horses’ mouth nutrition, feed and feeding, matrix multimedia
Frape, D. 2010, Equine Nutrition and Feeding, fourth edition, Wiley-Blackwell, p. 34-183-328
Loving, N.S, DVM, 2009, Nouveau manuel vétérinaire pour propriétaire de chevaux, edition vigot, translated from English by Patrick Morin, DVM, original version: All horse system go, 2006, P. 74-78-79-309-351-360
National research council (NRC) of the national academies, 2015, Nutrient Requirements of Horses, sixth revised edition, the national academy press
Tighe, M.N and Brown, M, 2004, Guide d’étude de l’ATSAQ pour les techniciens en santé animale, première edition, translated from English by Isabelle Carrière, original version : Mosby’s comprehensive study for veterinary technician, second edition, 2003, P. 275
Journal
Dacre K.J.P, Pirie R.S, Scudamore, S and Prince D.R, 2003, Hyperlipaemia and pancreatisis in pony with cushing’s disease, Equine Veterinary Education, Vol 15, No 4, 175-181
Frank, N, 2011, Equine Metabolic Syndrome, vet clin equine, Vol 27, 73-92
Giles, S.L, Nicol, C.J, Rands, S.A and Harris, P.A, 2015, Assessing the Seasonal Prevalence and Risk Factors for Nuchal Crest Adiposity in Domestic Horses and Ponies Using the Cresty Neck Score, Veterinary research, school of veterinary science, university of Bristol.
Glunk, E.C, Hathaway, M.R, Weber, W.J, Sheaffer, C.C, Martinson, K.L, 2014, The Effect of Hay Net Design on Rate of Forage Consumption When Feeding Adult Horses, Journal of Equine Veterinary Science, Elsevier, Vol 34, 986-991
Henneke, D.G, Potter, R, Kreoder, J.L, 1984, Body condition during pregnancy and lactation and reproduction efficiency of mares, Theriogeology, Vol 21, No 6, 897-909
Huntington, P, 2012, Dietary Factors in Equine Developmental Orthopedic Disease (no other information)
Jonhson, P.J, Wiedmeyer, C.E, LaCarrubba, A, Ganjam, V.K and Messer, N.T, 2012, Diabetes, Insulin Resistance and Metabolic Syndrome in Horses, Journal of Diabetes Science and Technology, Vol 6, No3, 534-540
Kaczmarek, K, Janicki, B, Głowska, M, 2016, Insulin resistance in the horse: a review, Journal of Applied Animal Reasearch, Vol. 44; NO. 1, 424–430
Shea Porr, C.A. and Crandell, K, 2008,Easy Keepers: Managing Horses Prone to Obesity, Virginia Cooperative Extension, Virginia state university
Silva, S.R, Payan-Carreire, R, Guedes, C.M, Coelho, S and Santos, A.S, 2016, Correlation Between Cresty Neck Scores and Post Mortem Nape Fat Measurement in Horses, Obtained After Photographic Image Analysis, research article, Acta Veterinaria Scandinavia
Treiber, K.H, Kronfeld, D.S, Hess, T.H, Byrd, B.M, Splan, R.K and  Burton Staniar, W, 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



dimanche 13 août 2017

Les éleveurs de chevaux canadiens


Introduction
Le cheval canadien est une des plus anciennes, si ce n’est pas LA plus ancienne, race de chevaux d’Amérique du Nord. Ces chevaux ont été un des piliers de la construction de notre pays, un pays dont ils tiennent leur nom. Ces chevaux étaient les parfaits petits chevaux de ferme : endurant, fort, résistant et d’une nature gentille et près de l’homme. C’est peut-être pour leur force et leur endurance qu’on les a surnommés « le petit cheval de fer ». Mais aujourd’hui, remplacés par les machines hydrauliques, ils ont perdu leur travail initial. Certains éleveurs travaillent très fort afin de revitaliser cette race et leur redonner leur popularité, commençant par montrer à quel point ce sont de bons chevaux de selle. Le cheval canadien est une toute petite race qui commence tout juste à se redresser après avoir frôlé l’extinction. Afin de mieux comprendre la race d’un point de vue génétique et historique, certains points seront abordés ici : l’histoire de la race, les enregistrements, le phénotype, le tempérament, l’impact de l’environnement sur le développement de la race, les problèmes génétiques rencontrés dans cette race et le futur de la race.

L'étalon Le noir Dynamo Kafka

Histoire
Le cheval canadien est censé être la première race de chevaux en Amérique du Nord. En fait, le « studbook » de cette race est le premier à voir été créé en Amérique du Nord, en 1889 (Khanshour et al, 2014). Selon certaines évidences, les chevaux fondateurs de la race canadienne ont été importés au Canada par le roi Louis XIV dans les années 1665 (lechevalcanadien.ca, 2008; Prystupa et al, 2012). À ce moment, aucune information n’a été notée au sujet des races qui auraient été importées à la nouvelle France. Des recherches récentes sur l’ADN de plusieurs races de chevaux ont démontré que le Canadien était génétiquement relié aux chevaux de traits, spécialement au percheron et au trait breton (Khanshour et al, 2014). Le cheval belge et le poney Dales seraient aussi reliés au Canadien. Il y aurait environ 100 chevaux qui auraient servi à la fondation de la race. Elle a évolué dans un climat rude et isolé, reproduit sans l’influence d’autres races ou d’autres lignées que les individus “souche” (chevalcanadien.ca, 2008). En 1784, la race comptait environ 30 000 individus (Gendron, 1993).  La combinaison d’une exportation massive pour la guerre et de l’industrialisation de l’agriculture a presque poussé cette race à l’extinction (Oklahoma state university, 1998). Le cheptel de chevaux canadien était estimé, en 2015, à 5000 individus (Leprince, 2015). La race est toujours en train de se remettre de la grande perte d’individus qui s’est produite jadis. Aujourd’hui, les éleveurs de chevaux canadiens ne se restreignent plus seulement au Canada, mais s’étendent maintenant aux États-Unis et en France (clrc.ca, 2014; lechevalcanadien.ca). Des chevaux canadiens sont également exportés à des particuliers en Europe (France, Allemagne et Suisse) et un peu partout aux É.-U..
Il y a plusieurs évidences que les Chevaux canadiens seraient une des races fondatrices de plusieurs autres races en Amérique du Nord : Cheval de selle américain, le Standardbred, le mustang des plaines du nord, mais plus spécialement important dans le développement de la race Morgan (Khanshour et al, 2014).

Les enregistrements
L'enregistrement du cheval canadien se fait en « livre fermé » séparé en deux catégories : pure race et grade.
Pure race : Les étalons doivent être aux moins 96.9% pures races canadiennes et les juments doivent être aux moins 93,8% pures races (clrc.ca, ND).
Grade : Les hongres  d’au moins 75% de sang pur canadien (aucun étalon n’est permis dans cette section) et les juments ayant entre 75% et 93,7% de sang pur (clrc.ca ND).
Pour être éligibles à l’enregistrement, les deux parents du poulain doivent être enregistrés, l’étalon doit avoir un certificat de type sanguin, avoir un certificat de reproduction et le nom du poulain devra commencer par la bonne lettre (chaque année de naissance possède sa propre lettre) (clrc.ca, NhasD).
Le nom d’enregistrement d’un poulain devrait toujours se composer comme suit : le nom de l’élevage, le nom de l’étalon et le nom du poulain (commençant avec la lettre de son année de naissance). Par exemple: Windigo Noireau Héritier. Ce cheval vient de la ferme Windigo, engendré par l’étalon Noireau et se nommant Héritier (H lettre de l’an 1998). Tous ses poulains futurs devront porter son nom au milieu.

L'étalon JP Casselman Wilfrid Dazzler


Phénotype de la race
Le standard de la race est divisé en 8 points ; la tête, l’encolure, les épaules, le corps, l’avant-main, l’arrière-main, les membres et l’apparence générale (lechevalcanadien.ca, 2008).
Quelques caractéristiques importantes de la race seraient (lechevalcanadien.ca, 2008; Oklahoma state university, 1998):
Crins : abondant, long, dense et ondulé
Corps : Dos court et fort, encolure de taille moyenne, large à sa base, épaule longue et musculeuse, poitrail profond, arrière-main fort et musclé, croupe légèrement inclinée.
Membres : Fort, membres antérieurs droits, membres postérieurs anglés, articulation bien définie, canons courts, sabot large et fort, Fanon épais et délicat, paturon robuste et de taille moyenne.
Tête : Courte, droite et mince, petites oreilles minces, yeux larges et brillants, naseaux larges, petite lèvre, joue bien définie et front plat.
Toise entre 14 et 16 mains (entre 1m42 et 1m62), mais on commence à retrouver des chevaux un peu plus grands.
Poids moyen : de 1000 à 1400 lbs
Robes ; en allant du plus commun au moins commun : noir, bai, alezan, palomino, isabelle et gris. Les listes (ou tout marquage facial) et les balzanes sont acceptées.

L'étalon JP Casselman Wilfrid Dazzler


Tempérament
Le cheval canadien est un cheval calme, intelligent et possède une personnalité vive. Il est un cheval loyal et un compagnon fiable et de confiance.


L’impact de l’environnement sur la race
L’environnement dans lequel la race a évolué a eu un gros impact sur sa génétique. En effet, avec les hivers longs et rigoureux du Québec, seuls les chevaux les plus rustiques et tolérants pouvaient survivre. L’hiver était très froid et on comptait une épaisse couche de neige, ce qui faisait que la nourriture n’était pas aussi facilement accessible qu’elle l’est aujourd’hui. Les chevaux devaient donc vivre dans des conditions très rudes tout en étant nourri au minimum de leurs besoins nutritif, ou moins. Dans les moments de froid extrême, il est recommandé d’augmenter de 2,5% l’apport énergétique minimal recommandé pour chaque degré Celsius sous -15°C (Cavanagh and Ternan, 2014). On peut donc se douter qu’une telle augmentation en apport nutritif quotidien n’était pas toujours possible à cette époque, les chevaux qui avaient une facilité à emmagasiner le gras (les « easy keeper ») étaient ceux qui avaient les meilleures chances de survie. Ils étaient également ceux qui étaient les plus utiles pour les fermiers. Les chevaux qui étaient résistants à l’insuline avaient également un avantage dans ce type de climat (Treiber et al, 2006) parce que cette résistance est probablement causée par un génotype « d’économie » (génotype d’économie d’énergie) (Kaczmarek et al, 2016). Cela a été relié à l’obésité, ce qui offrait à ce type de chevaux des réserves de gras pour passer l’hiver. Ces chevaux qui étaient plus résistants et avaient moins de mal à passer l’hiver étaient probablement plus fertiles et étaient choisis comme animaux de reproduction parce qu’ils étaient en meilleurs état que les individus moins résistants et pouvaient également travailler et se rendre utile sur la ferme même en hiver.



Maladie génétique
Il n’y a pas de maladies génétiques majeures ou de maladies spécifiques à la race chez le cheval canadien. Cependant, le cheval canadien possède certaines prédispositions génétiques au développement de maladies métabolique. Ces maladies ne sont pas spécifiques à cette race, le Canadien possède simplement une prédisposition génétique qui augmente ses chances de développer ce type de problèmes. Un petit exemple serait de dire qu’un Canadien à probablement plus de chance de développer de la fourbure qu’un Arabe.

Les problèmes métaboliques dont il est question  sont : Résistance à l’insuline (RI), fourbure et maladie de Cushing (MC). Ce qui était un formidable atout pour survivre jadis est devenu ce qui rend cette race plus apte à développer ces maladies métaboliques aujourd’hui. En autres mots, à l’époque, il était difficile d’avoir accès à du foin de qualité en hiver et il n’était pas disponible en grande quantité, les chevaux qui avaient plus de facilité à emmagasiner du gras étaient donc avantagés. Aujourd’hui l’abondance de foin de qualité en hiver fait que ces chevaux deviennent facilement obèses, ce qui peut grandement nuire à leur santé. Chez l’humain, le syndrome métabolique est maintenant perçu comme un trait héréditaire autosomique dominant. Cela pourrait donc également être le cas chez le cheval, il serait intéressant de faire des recherches à ce sujet. Comme discuté précédemment dans la section environnementale, les chevaux de type « easy keeper » et avec de la RI étaient plus apte à survivre. Ceci serait peut-être la raison pour laquelle nous rencontrons plus souvent ces problèmes chez cette race. Mais en fait, quels sont exactement ces problèmes ?

La résistance à l’insuline : La résistance à l’insuline se produit lorsque les tissus du corps deviennent plus résistants à l’insuline (ils y sont moins sensibles… La réponse à l’insuline est moins bonne), ce qui fait en sorte que ces tissus absorbent moins de glucose. Le glucose sera donc plus élevé dans le sang. L’obésité est un facteur important dans le développement de la RI : L’obésité et la RI sont positivement corrélé (Treiber et al, 2006). La RI est censé être déterminé par un nombre de facteurs génétiques (Kaczmarek et al, 2016) avec un déclencheur alimentaire : une diète riche en hydrate de carbone (glucide) ce qui exacerbe la RI (Treiber et al, 2006). Il est alors donc très important lorsque vous possédez un cheval qui pourrait avoir plus de chance de porter une génétique de type économique de prendre encore plus de précautions face à sa nutrition, une diète riche en hydrate de carbone n’est bonne pour aucun cheval, mais elle est spécialement mauvaise avec les chevaux de types rustiques. Il faut garder à l’œil la quantité de nourriture que ces chevaux reçoivent, il faut qu’ils reçoivent ses besoins nutritionnels de bas, mais il faut à tout prix éviter de les excéder afin d’éviter l’obésité. Comme il a été mentionné précédemment, le cheval canadien est génétiquement près des chevaux de trait et des poneys, ce qui veut probablement dire que, tout comme eux, les chevaux canadiens possèdent un métabolisme plus lent et plus efficace (Cavanagh and Ternan, 2014). Se fier à la charte nutritionnelle du NRC (National Research Council) sera un excellent point de départ afin de bien gérer l’alimentation de ces chevaux.

Fourbure: La fourbure est un problème majeur au sein de la population équine. Elle se produit lorsqu’il y a de l’inflammation dans la partie lamellaire du sabot du cheval. L’afflue sanguin y est alors perturbé et les lamelles commencent à nécroser et se détacher de la paroi interne du sabot. Cela a pour effet de retirer le support de la troisième phalange qui fera donc une rotation dans le pied. Le mécanisme exact de la fourbure n’est pas encore connu a 100%, mais il y a plusieurs suspicions du côté de la génétique : un gêne majeure ou certains gênes exprimées de façon dominante (Treiber et al, 2006) ce qui pourrait expliquer pourquoi deux chevaux obèses nourrit de la même façon et hébergé sous les mêmes conditions ne vont pas nécessairement développer tous les deux de la fourbure. Encore une fois, les gênes de type économique pourraient être une partie du problème. Comme avec la RI, la nutrition est une partie très importante du problème, mais avec la fourbure, le parage des sabots est également d’une grande importance. Il faut éviter les pieds de type : talons fuyants et pince trop longue (Loving, 2009). Le traitement de cette pathologie est donc de s’assurer que la nutrition et les pieds sont gérés de la bonne façon. En autres mots : une nutrition balancée et des sabots balancés (pince courte et pieds balancés). Il est également important de se renseigner sur ce que devrait avoir l’air un pied balancé, même si vous faites affaire avec un « professionnel » des sabots, cela ne vous garantit en rien qu’il sait balancer un sabot de la bonne façon.



Maladie de Cushing : La dysfonction de la glande pituitaire (Maladie de Cushing) est une maladie endocrine progressive qui se produit plus souvent chez les chevaux plus âgés (McFarlane, 2007). C’est en fait une dysfonction de la glande pituitaire qui change la sécrétion de l’ACTH et du cortisol (The Pituitary Foundation, 2015), ce qui entrainerait des changements métaboliques. Cette maladie est perçue comme étant génétique avec des déclencheurs environnementaux (McFarlane, 2007). Tous les chevaux peuvent développer la MC, mais certaines races sont plus à risque que d’autres. Encore une fois, bien gérer la nutrition est un facteur très important, mais il faut également porter une attention particulière à l’environnement dans lequel le cheval est hébergé et garder un parage balancé (comme ils sont plus susceptibles de fourber). De la médication peut également être utilisé afin de garder un bon contrôle sur la maladie, mais la médication seule ne suffira pas, il faut également offrir les éléments décrits ci-haut pour un contrôle optimal.

Sommairement, ces maladies ne sont pas causées par une seule chose, mais bien par un ensemble de facteurs incluant des gênes dominant ou un ensemble de gênes influencé par l’environnement dans lequel le cheval est hébergé et par la façon dont sa nutrition est gérée. Il est donc important de bien gérer ses facteurs, mais également de porter une attention particulière au parage du cheval. Comme on dit : pas de pieds, pas de cheval.

Le futur de la race 
La race comporte un petit cheptel, mais ce petit cheptel possède une très grande diversité génétique, ce qui veut dire que c’est toujours une race viable et saine avec un très faible taux de consanguinité (Khanshour et al, 2014). Le taux de consanguinité est un très bon indicateur de santé génétique chez une race. De plus, le cheval canadien porte toujours à ce jour des allèles génétiques rares (Khanshour, 2014) ce qui le rend encore plus intéressant du côté de la génétique.

Le cheval canadien détient une grande importance dans notre histoire, ces chevaux ont été un important pilier du développement de notre pays. Il serait extrêmement triste de perdre une aussi grosse part de notre héritage. Ces chevaux ont été reconnus comme faisant parti de l’héritage par le gouvernement québécois en 1999 et ils sont devenus la race nationale du Canada en 2002 (lechevalcanadien.ca, 2008). En dépit de ces faits, le gouvernement est inactif face à la conservation de cette race. Il ne fait absolument rien de concret afin de les préserver notre petit trésor national.

Pourquoi cette race a besoin d’aide ? Avec l’industrialisation agricole et l’exode rural, les races qui étaient utilisées autrefois en agriculture ont perdu en popularité. Les chevaux canadiens peuvent avoir des similarités avec les chevaux de trait, mais ils sont physiquement très différents. Ils sont plus légers (moins robuste du point de vue squelettique) ce qui les rendent plus aptes à être montés. Soyons honnêtes, ce n’est pas une race de chevaux de grand prix, ou de champion de course, mais ce sont les parfaits chevaux de loisirs. Ces chevaux sont parfaits pour les cavaliers qui souhaitent avoir du plaisir et essayer un peu toutes les disciplines. Ils sont endurants, forts et fiables. Une étude de Canada Hippique à démontrer que 75% des cavaliers adultes sont des cavaliers de loisirs (equestrian.ca, 2011), ce qui veut dire que 75% des cavaliers pourraient avoir beaucoup de plaisir avec un cheval canadien. En dépit du fait qu’ils ne sont pas des chevaux de grand prix, ils peuvent tout de même être très compétitifs contre d’autres races, surtout en dressage. Ils sont vus de plus en plus dans les carrières de dressage (et de concours en général) et ne sont pas du tout désavantagés face aux autres chevaux, ils finissent même souvent dans les rubans.

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

Quelques éleveurs essaient de suivre ce courant : produisant des Canadiens qui sont un peu plus légers et grands que leur ancêtre. Cela est fait dans le but de les rendre un peu plus sportifs. Ce qui pourrait convaincre plus de gens à les utiliser en concours. Jouer avec le phénotype d’une race doit cependant être fait prudemment. Une des raisons est parce qu’il ne faut pas dénaturer la race, d’une façon telle que le cheval ne ressemble plus du tout au standard de la race dont il est issu. Une secondaire raison est que pour changer un phénotype, il faut croiser des chevaux qui sont phénotypiquement similaires (le physique se ressemble) (Equine Genetics Workbook, 2013). Cela doit être fait de la bonne façon, parce que sinon, cela peut mener à de la consanguinité. Utiliser le croisement de type consanguin peut être utile, si fait de la bonne façon (chevaux exempt de maladies génétiques, éviter de pousser la consanguinité trop loin, etc.), mais comme la race a un coefficient de consanguinité très faible et une variété génétique très grande, il serait vraiment dommage de changer cela pour quelques centimètres de plus au garrot et un physique un peu plus avantageux. Les éleveurs font des efforts incroyables afin de revitaliser la race et afin de la rendre populaire à nouveau. L’élevage de chevaux n’est pas facile, spécialement avec les races de chevaux plus rustiques, parce que les gens sont attirés par de grands et délicats chevaux de concours bien flashy, alors que la plupart n’auront jamais besoin de chevaux de races aussi spécialisées. Mais, par chance, il y a encore des gens passionnés qui tentent de sauver cette race. Les gens devraient également se souvenir que des chevaux rustiques ont souvent une meilleure santé, moins de blessures et son plus facile (et moins couteux) à garder en bons états.

Canadream Alex Shining Star sur le parcours de cross country

Cette race mérite d’être sauvée, pour la part importante qu’ils ont jouée dans notre histoire, mais également parce que ce sont d’excellents chevaux qui ont beaucoup à offrir. C’est une race saine, avec une grande diversité génétique. Le Canada devrait commencer à être fier de sa race nationale et commencer à la redécouvrir..

Conclusion
En conclusion, le cheval canadien est un petit trésor national. C’est une race qui a joué un rôle très important dans la construction du Canada et son histoire. Ces chevaux ont été de grands partenaires des fermiers d’autrefois qui tentaient de survivre dans le climat hostile de la nouvelle France, les aidant dans leur vie de tous les jours, sur la ferme, comme moyen de transport, etc. Ce serait absolument honteux de perdre cet héritage. Surtout sachant que la race est aussi saine. Ils ont peut-être une prédisposition génétique pour certaines maladies, mais une bonne gestion de leur alimentation, leurs sabots et leur environnement fera toute la différence. Sachant que cette race est plus à risque, elle laisse donc une chance au propriétaire de faire une bonne gestion dès le départ afin d’éviter le développement de ces problèmes. Cela ne devrait pas stopper quelqu’un de faire l’acquisition d’un cheval canadien, plusieurs races de chevaux ont des problèmes génétiques plus ou moins importants, certaines très populaire ont même beaucoup de problèmes génétiques importants, ce qui ne les empêche pas d’être populaire. Le cheval canadien à beaucoup à offrir à son futur propriétaire, beaucoup de plaisir dans plusieurs disciplines et capable de compétitionner à très bon niveau.
N’oublions jamais ceci: nous élevons pour nos enfants, les chevaux de nos pères.

Canadream Kelbeck Belle-de-mai

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Livre
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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
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