The outside wrapper should be in good condition, not punctured or ripped and not overly faded. You can check this by peeling a bit of the wrap back and seeing if it is a different colour underneath. If it is faded, it suggest the bale has spent a long time in the sun and the wrap may have started to go porous and let oxygen in.
There should be plenty of layers of wrap. The plastic used for wrapping bales is not actually 100% air tight. Each layer of wrap reduces the porosity by about 50%. So 6 layers of wrap will let half as much air in as 4 layers, and 8 layers will let half as much in again. We suggest using at least 8 layers for the best protection and sealing.
There should also be no visible tears or ‘repairs’ to the bale. Haylage patches or tape, as long as it has been applied in the dry, not allowed moisture in and has created an air tight seal will seal the bale up again if it has been punctured, but you should inspect the patch and if in doubt not accept the bale. Never accept a bale where the wrap has been obviously damaged unless it was damaged very recently.
Ideally the bales should be covered with netting or a haylage cover to protect the bales from being punctured by birds. Small holes which puncture the wrap from birds landing on the bales or pecking them are likely to be the biggest reason for bales being damaged and then becoming unsuitable to feed to horses.
What should good horse haylage inside the bale look like?
- Should be a bright golden colour and look like a damper version of hay. We have found that horses prefer haylage which is more like hay.
- Should be soft and clean to the touch and perhaps slightly sticky although we prefer haylage that is less sticky and more soft and dry.
- When you first unwrap it, it should feel warm, the same temperature as a nice warm summers day.
What should good horse haylage smell like?
- It should smell like a summer’s day.
What does bad horse haylage look like?
- It is a dark brown or very dark colour indicating excessive heating causing the forage to caramalise. This reduces the digestibility of the protein even though the horses may eat it up.
- There are lots of dark brown leaves and stems. This can mean that dead material was incorporated into the crop. This can be left over from a previous crop or could be a result of the crop being over mature when harvested. As long as the rest of the matter looks and smells ok, this is generally not a problem apart from the visual impact.
- Another reason for the presence of dark leaves is that these are herbs such as plantains and other beneficial plants. The dark colour is because these type of plants are full of anti-oxidants. In this situation the presence of these dark leaves is beneficial.
- There are moulds or other growth on the haylage. This will indicate that there was insufficient lactic acid produced to preserve it, or the wrap has been damaged. Where the wrap is intact it is possible the haylage was too dry when wrapped or that there are not sufficient soluble sugars in the grass to complete fermentation. In these cases the pH level will not fall low enough to prevent the growth of undesirable moulds and fungi.
- There are coloured moulds growing on it. These coloured moulds can be very dangerous and this should never be fed to horses.
- White spots that do not smell may be yeast. Yeast may grow slowly on haylage that had high levels of sugar in it. It can also grow where there was a pocket of oxygen or if it was inadequately pressed failing to remove all the oxygen. This is because yeast can grow both aerobically and anaerobically. Generally, yeast is not bad for horses, but frequent occurrences of it on bales would suggest a deeper problem.
What does bad horse haylage smell like?
- If you smell a putrid or rancid smell from the haylage then this is of concern. Putrid smells indicate the presence of butyric acid from Clostridium bacteria and horses should not eat this haylage. This type of problem occurs mainly when haylage has been made too wet. In this situation there will be insufficient lactic acid produced to preserve, pickle and ferment the haylage.
- Yeasty bread, alcoholic or fruity smells indicate the presence of yeast growth. If you can smell it there is probably too much yeast growth and fermentation will have suffered and the aerobic stability may be poor.
- Vinegar odours suggest an excess of acetic acid. This is the result of a different type of fermentation when there was a lack of lactic acid producing bacteria. Horses are usually reluctant to eat it if it smells like this.
- Burnt odours indicate excessive heating took place and there was something serious wrong with the fermentation process that occurred.
What does bad haylage feel like?
- It should not be hot to touch. If it is hot to touch it is either still going through fermentation or it is aerobically respiring (ie. rotting).
- If it is slimy and wet to touch it was baled too wet and probably has not fermented properly. This will go off very quickly and care should be taken when feeding so that horses do not have their digestive systems upset.
Problems with horse haylage
One of the biggest problems with horse haylage is the presence of clostridium botulinium organism which, as discussed, tends to proliferate in very wet matter. Clostridia are bacteria which live in soil and can contaminate the grass crop due to soil splash or the crop being cut too close to the ground. However if it is dried to a dry matter above 50% then it will be too dry to support the colstridia to multiple.
Haylage that is very acidic and wet may upset the hind gut of the horse leading to colic or even laminitis.
Some people say that haylage is richer than hay. This is a myth as it is impossible to tell the nutritional value of a forage just by looking at it. The nutritional value of any forage is determined by the time of year it was cut and the way it was handled after cutting. For example June cut forages tend to be higher in both protein and sugar than later cuts. The species of grass or grasses and plants contained within the bale also influences the nutritional content greatly. The main thing to understand is that the only way you can find out the levels of any nutritional portion is to scientifically test a representative sample.