Long periods of stall rest used to be part of the healing process after musculoskeletal injury or surgery. This regimen allowed healing but also resulted in bulky scar tissue, adhesions, and losses in range of motion, flexibility, balance, and muscle strength.
Each horse and injury must be evaluated on an individual basis to determine the best course of treatment and recovery.
Newer advice is to put recovering horses back into light work at a much earlier point. Though a short period of immobilization is important immediately after severe tears and fractures, early mobilization has been shown to increase blood and lymph flow, and the tissue tension caused by movement stimulates soft tissue repair and improves fiber alignment in healing tissues. In one study, there was a 60% improvement in tendon Type 1 collagen deposition and a 20% improvement in range of motion and the ability of an injured tendon to handle ground reaction forces. Also, long immobilization doesn’t guarantee a better outcome, and early mobilization doesn’t lead to an increased rate of reinjury.
While it’s difficult to quantify the psychological effect of stall confinement, some horses seem to become depressed while others show increased agitation when they are kept in stalls with no company, turnout, or exercise. Each horse and injury must be evaluated on an individual basis to determine the best course of treatment and recovery.
Fecal egg per gram (EPG) counts are valuable to actually determine the number of worm eggs in a horse’s manure. Routine fecal floats determine if parasite eggs are present but cannot differentiate a heavy-shedding horse from one shedding fewer worm eggs. Manure for EPG determination is weighed, floated in a standard volume-of-egg flotation solution, and worm eggs are counted under a microscope using a special slide.
The most commonly observed worm egg is called a typical strongyle-type ova (eggs) because the eggs of small and large strongyles look alike. Small strongyles are the most common internal parasite of horses. Roundworm eggs are also observed, especially in younger horses. Tapeworm eggs are seldom seen, even when horses are infected with large numbers of tapeworms.
An excellent study from Denmark found that horses tend to be consistent in the amount of worm eggs shed in their manure. Less than 200 EPG is considered a low level of shedding. Horses that had two previous EPG counts performed six months apart that were both less than 200 EPG had an 84% chance that their third EPG count would also be low. Similarly, if a horse had two previous EPG counts greater than 200, the chance of being greater than 200 EPG on the third count was 59%. This demonstrated that horses with low EPG counts tend to keep low EPG counts and those that are high also tend to stay high.
These findings help to target deworming to reduce resistance and allow for the classification of horses into low or high EPG shedders. Horses that consistently have low EPG counts do not require frequent deworming, and deworming twice a year is probably sufficient. Horses that have a consistently high EPG count can be segregated to reduce overall pasture parasite egg contamination, and these horses may benefit from more frequent deworming.
Your veterinarian can perform EPG counts and is the best source of information to tailor a deworming program that is best for your farm. EPG counts also help slow the development of resistance to dewormers, and less frequent deworming reduces costs.
Reference: Nielsen, M.K., N. Haaning, and S.N. Olsen. 2006. Strongyle egg shedding consistency in horses on farms using selective therapy in Denmark. Veterinary Parasitology 135:333-335.
Glucosamine Hydrochloride vs. Sulfate
There is discussion over which of the two glucosamine salts, hydrochloride or sulfate, is preferred for the treatment of osteoarthritis.
The answer is straightforward - both salts, in the pure form, deliver equally effective amounts of the desired glucosamine to joint cartilage. If there is a preference, it should be based on relative purity and economics.
Historically, the sulfate was used for the initial European clinical studies because it was made available for that purpose by an Italian pharmaceutical company which had a proprietary position on the sulfate. Thus, it was to their marketing advantage to supply only the sulfate and ignore the hydrochloride.
The original researchers, however, clearly relate all of the observed benefits relative to osteoarthritis to "glucosamine" not to the sulfate. When ingested, glucosamine sulfate is fully ionized in the stomach by the relatively strong concentration of hydrochloric acid (pH 1 - 3) naturally present. As a result, glucosamine ions and sulfate ions are thoroughly mixed with an overwhelming number of chloride and hydrogen ions from the hydrochloric acid. If you could stop at this point and recover the glucosamine salt, you would get 99+% glucosamine hydrochloride as the sulfate is essentially lost due to its very low concentration relative to the extremely large amount of hydrochloric acid present.
As reported by Setnikar1, 54% of the glucosamine that moves into the small intestine (pH 6.8) exists in its un-ionized, amine form (not a salt at all) while 46% is ionized (the amine group is protenated and positively charged). In the blood at pH 7.4, 75% of the glucosamine is present as the neutral amine while only 25% is ionized. Since ionization or high polarity is usually an obstacle in the crossing of cellular membranes, the ability of glucosamine to exist predominantly in its less polar, un-ionized form in the small intestine and, even more so, in the blood contributes directly to its bioavailability. The specific salt form is relevant only as a convenient delivery vehicle with the proviso that the salt must readily dissolve (ionize) in stomach acid when ingested - the hydrochloride and the sulfate equally meet this requirement.
Conclusion
This systematic review and meta-analysis found that chondroitin, glucosamine or a combination of both do not have a useful clinical effect in the treatment of osteoarthritis. The supplements were also not found to be harmful. This study benefited from an extensive search for studies on these supplements, and made good use of all the data available by combining results in the network meta-analysis.
However, as with all meta-analyses, the studies included varied in a number of ways, including the severity of the osteoarthritis studied, the main joint involved, or how long the patients were followed up for. This is called heterogeneity. Using the network meta-analysis, the researchers were able to combine evidence from different comparisons of the supplements. This means that the heterogeneity was more complex to calculate, but the researchers say it was low enough to allow them to combine the trials reliably.
A meta-analysis was needed as the randomised controlled trials involving these supplements were small. While it appears from this study that the effects of these supplements are limited, a small effect in a small group of patients could have had a relatively large effect on the overall results. A large randomised controlled trial on a clinically defined group of patients is the best way to assess the effectiveness of these treatments.
Glucosamine and chondroitin are not currently part of the treatment strategy for osteoarthritis recommended by NICE. Patients should consult their GP about the best pain-management options available to them.
Equine Doseages
While "exact" recommended dosages of many ingredients are not available, the following ingredient doses can be used as general guidelines for an average 1,100-pound horse, based on the results of scientific studies: