My sister just had her 8 year old TB, Senator, shipped up to our farm in Pennsylvania from Texas. I'm not sure if you're familiar with the two state's climates, but they could not be more different this time of year. When Senator left Texas, it was 75 degrees and sunny - he had shed his "winter" coat and was used to the sandy soil and coastal hay. When he arrived in Pennsylvania, it was 30 degrees and we just had a massive snow storm.
Since he was thrown into a completely new environment, he was in quarantine for about two weeks before he was able to get close to our herd. This leads me to answer the question: How do I introduce a new horse into an established mixed herd? We have 4 geldings and one mare. (I'll answer how to transition him to a different hay and grain later).
Step 1: Understand the pecking order of the established herd
- By knowing who is most submissive and the most dominant, you have the best chance to introduce a new horse without any/limited complications
Step 2: Allow the new horse(s) and the established herd to see each other from a distance for 1-2 weeks
- I did this by keeping the Senator in a round pen that is located about 30 yards from our established herd's pasture
Step 3: Allow the new horse to meet the most submissive horse through a fence or stall divider
- If you do this through a fence, ensure that you have a long lead on the new horse for your safety and be ready for any striking, squealing, snorting, or biting
Step 4: Repeat step 3 with the next dominant horse and work your way up to the most herd leader
Step 5: Put the new horse in a pasture beside the established herd's pasture
- If you are able to complete this step, it is really helpful to allow the horse's to see each other on their own terms
- Even though they have met with you holding the new horse, be prepared for the horses to begin establishing their pecking order - just be sure that your fencing is safe and appropriate for the type of horse that you have
- Feed the new horse and the established herd on opposite sides of the fence so they become used to eating in the same space
Step 6: After a week/couple of weeks of step 5, introduce the new horse with the most submissive member of the established herd
- Continue to add the next dominant horse to the pasture until you finally add the most dominant horse
Step 7: Once all of the horses have been introduced to the new horse, still be prepared for any squealing, kicking (take off any hind shoes, if necessary), biting, or chasing
- Ensure that your pasture:
1. Is large enough that the horse's can run away from each other, if necessary
2. Does not have any areas that horse's can get stuck or pinned in
3. Is free from any large holes that can potentially hurt the horses if they are running
Step 8: Watch and wait
- It can take up to 3 months for the established herd's pecking order to be re-established
- As the new horse is integrated into the herd, friendships may change and horse's personalities in the pasture may be altered as well
Senator was successfully integrated into the herd with *zero* fighting or any issue at all. I followed all of the steps outlined above and so far, he has been doing very well in the herd. They are still figuring out exactly who is dominant over the others, but in a mixed herd (1 moody mare and 5 geldings), the worst they have done is pinned their ears at each other.