It spite of it dropping below freezing for the next two night spring is upon us and I would like to talk of the hazard of spring grass. I am sure that the most of you know that spring grass can, if your horse is allowed to gorge upon it as it would like to, lead to a case of laminitis if not founder. Remember all founder is laminitis but not all laminitis is founder. Founder is either the rotation or sinking of the pedal bone
The reason spring grass is dangerous to some horses is that the grass did not stop stop its photosynthesis factory, it just redirected its output to it carbohydrates to be stored in the base and its roots. Come spring wake up the plants carbohydrates its stored carbohydrates into their growing blades as simple sugars.
This is the current theory carbohydrate overload: If a horse is given grain in excess or eats grass that is under stress and has accumulated excess non-structural carbohydrates (NSC, i.e. sugars, starch or fructan), it may be unable to digest all of the carbohydrate in the foregut. The excess then moves on to the hindgut and ferments in the cecum. The presence of this fermenting carbohydrate in the cecum causes proliferation of lactic acid bacteria and an increase in acidity. This process kills beneficial bacteria, which ferment fiber. The endotoxins and exotoxins may then be absorbed into the bloodstream, due to increased gut permeability, caused by irritation of the gut lining by increased acidity. The result is body-wide inflammation, but particularly in the lamina of the feet, where swelling tissues have no place to expand without injury to other structures. This results in laminitis. Wikipedia
This warning also apply to grass that grows after a long drought, it too has been storing its carbohydrates in the base and its roots, and when it rains it comes up just like spring grass.
Irrespective of the mechanism of how a carbohydrate overload can lead to your horse developing laminitis, many horses do, so beware of spring grass. It can also lead to colic as the bacteria in your horse's gut must be of the type that can get along with the food that goes into its stomach. This is why when changing the type of feed that you give your horse you should do it in small increment over a period of time to allow the bacteria time to adjust.
I am not preaching, if you know this already, wonderful, if you did not, now you do. Beware spring grass.
