Q: I do not have much space for hay storage on my farm, so I only buy about 10 bales at a time from my local feed store for my pony. They get their hay from various sources so there is little to no consistency. How can I make these constant changes easier on my pony? Should I get my hay tested with each shipment to make sure it is meeting his nutritional requirements?

A: You’re correct in being concerned about the impact of hay variability on your pony’s nutritional well-being. This is an issue I see fairly frequently, even with large boarding facilities, because it can be difficult to source enough hay for the year and have the space to store it.

I have two main concerns with continually changing the forage source in your pony’s diet. First, when you change the fiber type abruptly, it can shock the microbes in the horse’s gastrointestinal tract and cause digestive upset. Second, maintaining a balanced diet that is optimal for your pony can be challenging when you are unaware of the forage’s nutritional content.

Finding a reliable hay supplier is easier said than done; however, if you can travel to pick up the hay, I recommend inquiring with local hay suppliers about purchasing from them regularly. They might be willing to store hay for you, which could increase the consistency of your 10-bale batches.

If you cannot change hay suppliers or none in your area have a storage system, testing every shipment to make sure it is adequate for your pony is the gold standard. Hay batches often have large variations in nutritional values such as protein, energy, minerals, sugars, and even fiber digestibility. Maintaining your pony on a quality ration balancer that provides a digestible source of vitamins and minerals will reduce the risk of dietary deficiencies from the forage.

Since you are consistently getting new shipments of hay, testing every single batch can become costly. So, despite this being the gold standard practice, it might not be practical. If you cannot test each shipment, at least test a few batches so you can better understand the forage’s variability.

As mentioned, one of the main concerns with abrupt fiber changes is the risk of digestive upset. The large population of microbes in the equine gastrointestinal tract gets accustomed and adapts to the day-to-day diet. Therefore, when your pony switches from one hay type to another frequently, it can be challenging to maintain optimal gut health. A simple way to reduce the risk of gastrointestinal upset when switching hay types is to save a couple of bales (even just two or three) to mix with the new batch of hay.

Get your new shipment of hay while you still have a couple of bales remaining from the last batch. Then begin to feed the new forage in combination with the previous batch. You can start with 25% of the new forage and 75% of the previous batch. Ideally, you would maintain this ratio for a couple of days prior to moving to a 50/50 split. From there, you would continue to increase the proportion of new hay in the diet as you decrease the previous batch. In a perfect situation this transition would happen over seven to 14 days, but any type of slower transition is better than an abrupt change. The slow transition will reduce the shock on your pony’s gastrointestinal tract and allow the microbial population time to adapt to the new forage slowly.

Sourcing hay can be challenging, especially when storage is limited; however, with careful management, you can reduce the risk of gastrointestinal upset for your pony. Additionally, testing hay when possible and using a quality ration balancer can reduce the risk of nutrient deficiencies in your pony’s diet.