Eindeloze discussie die vooral gestoeld is op meningen helaas.. Ik ga me er verder niet in mengen maar wilde deze tekst toevoegen. Geschreven door een quarter trainer in de VS. Waar het nog altijd gebruikelijk is om de paarden te starten tussen de 20 en 24 maanden. Naar mijn meningen draagt ze enorm interessante punten aan.
Citaat:
Chelsea Schneider:
I often read with the mass coverage of social media, how starting a horse as a 2-year-old or a coming 2-year-old will “cripple” them. "They will be done by the time they are 5." "Poor thing won't be able to walk at 10." We see lots of generic horse owners have their outside perspectives and opinions that showing them as 3, 4, 5 and 6 year olds is too early. We read/hear you should wait to start them until they are at least 4 year olds. However, I beg to differ for many reasons the big one is science and proven facts. So sit down and take a read.
The famous Wolff’s Law. Don't know what it is? Let me explain a little. It’s not an opinion, it’s not a hypothesis, it’s a law that’s been proven time and time again across all animals. Developed by the German anatomist Julius Wolff in the 19th century, states that bone in a healthy person or animal will adapt to the loads under which it is placed. Bone is constantly being formed and resorbed. Bone growth occurs when calcified matrix is formed faster than it is resorbed. Diameter growth occurs when matrix deposition occurs on the outer surface of the bone. Linear growth in long bones occurs at epiphyseal plates. These plates are between the epiphyses and diaphysis of the bone. Columns of chondrocytes on the epiphyseal side divide continuously causing this growth.
As the collagen layer thickens, older collagen calcifies and older chondrocytes deteriorate. Osteoblasts lay down a bone matrix on top of a cartilage base. The shaft lengthens as new bone is added at the ends. As long as the epiphyseal plate is active, long bone growth continues. Bone will constantly remodel throughout life. It is necessary to tell the bone where the areas of stress are going to be so that it can remodel and strengthen in preparation for the event. Riding a horse in general as a 2 year old the bones start to feel where the weight is being applied and the body goes to work. Bone cells, in particular osteocytes, are extremely sensitive to mechanical stress, a quality that is linked to the process of mechanical adaptation. Bone remolding consists of two stages, resorption and formation. During resorption, old bone tissue is broken down and removed by special cells called osteoclasts. Once this has been done, bone formation begins and new bone tissue is laid down to replace the old. This task is performed by special cells called osteoblasts. Osteoblasts produce collagen, enzymes, and other proteins that make up the organic portion of the bone matrix. Vigorous exercise and healthful diet with adequate calcium, protein, and vitamin D are essential in achieving sufficient bone mass during the bone adaptation process. Just like muscle, bones respond to certain kinds of training by hypertrophying. By putting enormous stress on bones, cartilage inside bones may become bones, causing plates to close. The actual amount of growth in a bone depends upon the NEED for it. As force is applied, the bone will remodel itself to better handle the force. In a reining horses, for example, the bones of the legs and feet strengthen to handle the impact of stopping a turning. Although this will alter throughout life, the main effects will be seen during the period of growth, when remodeling is most evident. It is in this period that the actual length of a limb bone is being determined. The actual amount of growth in a bone depends upon the need for it. In order for horses to be strong throughout life they need the dense bones which only happens when exercise, weight and pressure is applied. In relation to soft tissue, Davis’s Law explains how soft tissue remolds itself according to imposed demands as well just like the bone.
You can look at it this way, if you had a child and that child only roamed around the house until they were 15 and then you put a 30lb back pack on them and asked them to run to the other end of a football field they would break a bone or tear a ligament before they hit the 10-yard line. Why? Their bones are thin and weak along with many other things in their body. Their body leaned during their growing phase there was no pressure the bones only grew for house hold walking, not sports. I hear and see constantly people who wait to start their horses until they are 6,7, 10 and they think because they are mature now they are ready to be started, so because of their age they start them into a training program as if they have been rode their whole lives and what’s the first thing that happens? They go lame, they tear a suspensory, they break their coffin bone, they break their sesamoid bone, spiral fracture of the cannon bone, soft tissue damage. Why does this happen? Because they were the kid who lived in the house till they were 15 that had a backpack put on and where asked to run. Even with a slow start the chance of injury compared to one started as a 2-year-old are massive. There is significant study and proof of horses raced at the age of 2 compared to being raced at 4 sustained far less injuries to the 4 year olds who frequently came up lame and many sustained career ending injuries.
Exercise, pressure and weight are major essential tools for bone growth. There are a few other things that are your best friend lets talk about those.
Ever wonder why people are so high on the Theraplate? The vibrating platform works by triggering bones to generate tiny electric fields. These tiny currents may turn on genes that affect bone remodeling and growth. That’s when a series of experiments showed that bone is piezoelectric, meaning that bending or deforming its crystal structure creates local electric currents. These currents where quickly linked to bone growth in studies that seemed to explain why exercise strengthens bones(riding) and immobilization (being left in a pasture) weakens them. So, when you done with your ride for the day or a great way to warm up the body to exercise is to put them on the theraplate.
Ultimately You can still sit and attempt to judge someone for starting a 2-year-old or a coming two-year-old but it all boils down to science and knowing what you’re doing. They are individuals after all. Some can take a lot of pressure and some cannot. Bone growth however no matter what comes from exercise and weight in order to building and strengthening the bones needed for that horse’s career path. And that starts at a young age not when they are 5. Along with this, many people's personal opinions most with no experience raising horses from conception to riding let alone starting horses automatically think a 2 year old being started means they go into some rigorous 5/6 day a week 45-60min work out. When In fact it's more around 2-3 days a week for 2-5 mins for the first 30-60 days in which the program goes to 3/4 days a week for 10-15 mins and steadily climbs from there. A horse being started as a 2 year old is not being rode as a horse with a year or two of riding on it. People like to ignore that or just don't know. That's again where each one is an individual and you have to listen to what they are capable of handling. Other things do play a large roll in a strong horse for a long healthy life such as nutrition. So let's break this down even more.
Bones are a fascinating subject in general, from the wide general perspective we just covered down to the cellular level which can be genetic and what you are feeding them. There are two types of bones, compact and spongy. Compact being the dense hard bone and spongy being the cancellous bone which does not contain osteons. Then you have the four main principle types of bone cells in the tissue which are osteoprogenitor cells, osteoblasts, osteocytes and osteoclasts. Then you have an abundant of mineral salts, primarily hydroxyapatite, some calcium carbon at and most of all calcium phosphate. These salts are the framework of collagen fibers which is a process we have all heard called calcification. Mineral salts confer hardness on the bone while collagen fibers give the bone tensile strength (bend to a certain point and not break.)
Now with compact bone you have something called osteons which is a community of cells called osteocytes, you have a central canal which houses the periosteal arteries and veins to feed and remove the waste and CO2 created by the cells within the bone. The nutrient artery sends branches into the central Haversian canals to provide for osteocytes. The arty continues into the medullae to supple blood for the marrow and osteocells via the epiphyseal artery. The periosteal arteries pass through the Volkman’s canal to multitude of vessels that supply the outer compact bone. Now while I’m sure this sounds like a bunch of crazy talk I want you to think about your feed program. Sweet feeds that are extremely high in sugar content, do what to the blood? They make the blood thicker and impair the flow of the blood. When the blood gets down to the periosteal arteries that feed the bone its nutrients needed for strong healthy bone growth they are minimized. Think of sucking water through a straw versus a thick milk shake. When the blood has a very limited flow through the canal to the outer layer of bone it can cause the bone to not fully develop leaving holes or as we dread to hear on a pre purchase exam an OCD. So when it comes down to growing strong healthy stock your number one concern should always be your feed program from in-utero to old age. Followed by them having the proper amount of exercise and weight to grow the density of the bones, tendons, and ligaments. Now yes, there are other things that can cause an OCD or cause one to not heal however nutrients in the bone is the biggest. Your feed program feeds into the overall strength and development of the skeleton from in-utero to the day they die.
I have always been a big advocate for the equine athlete. After all we are the ones asking them to perform. Just remember every horse is an individual. You can cripple a long yearling or a 10 year old the same it's all in how you ride them, grow them and care for them. Just because one can handle it doesn't mean the other can wether that's structurally or mentally.
Hope you enjoyed the read
(Edit: This was a post to my personal wall, it's not professionally written or cited as it sure wasn't intended for the 800+ shares it has received so far. Therefor I listed some sources below)
Sources:
- Professor John Adams
- Mosby's Medical Dictionary, 9th edition. © 2009, Elsevier.
- How bone remodeling works, Ryan Nguyen
- American College of Veterinary Surgeons
- College of Veterinary Medicine & Biomedical Sciences
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