Agree with Liz that it would be far better to breed from a registered Tamworth, not just a birth notified one, which signifies only that her parents were both pedigree but nothing about her own standard. You will be keeping your sow for years, and a good quality registered pig opens up your potential for future sales of breed standard weaners as well as weaners for meat.
If however your ginger pig is good enough, I would be inclined to get one or more female weaners as the companion pig, and use AI on the ginger pig, which is very easy to use and generally completely successful. Or use a stud boar; owning one would be crazy for a single sow. Even so, you have to plan the timing/ages/purpose of the companion pigs with a great deal of care. One option is to have the companion pig ready to go for slaughter when the sow farrows. In your case, if you get your 6 month old gilt pregnant at 8 months so that she farrows at 12 months old, 6 months from now, even if you were to get in the youngest 2 month old weaners as companions now, they would not be able to go to slaughter for another 6 months, ie. 8 months old, which could be longer than you would have liked. Or you could stagger when you get companion weaners, starting with one now to go to slaughter at 6 months old, and then overlapping with a second younger one, in say 3 months time.
But that generates another timing issue you need to think about. The sow can be alone on her own for the week pre-farrowing and 7-8 weeks with the piglets, but if you still have a single companion pig around, this one is now on its own and will need a companion itself. And at the end of the 8 weeks when the piglets are weaned, the sow needs to be completely separated from her piglets for at least 2 weeks, and ideally, to be put with one or more companion pigs.
Sorry to make all this sound so complicated but you need to think it all through in detail. Including, what time of year your home bred weaners will be ready for sale, and whether anyone will want to buy them then. In my opinion, by far the best solution is to aim for two same age breeding gilts/sows, and to try and have them pregnant and farrowing at almost the same time every time, so they can always be companions to each other, barring any unforeseen disasters.
And finally, as I said in earlier posts on how this all started, with ery, three of my home bred, ery-vaccinated at 6 and 10 week old weaners caught it, albeit it exactly 3 weeks after a sow returned from being served in Somerset who may have brought it back with her, but do bear in mind that the vaccination per se is not a 100% guarantee that they won't catch ery, possibly more mildly, later on.
Have fun working it all out!
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