Mare Lines in Need of Conservation - Part 1
/I have previously explored the relative rareness of the Sleddale mare lines (click here). I had a very personal interest in the topic because I have a Sleddale line mare. In the process, though, I was reminded of Dr. Claire Winton’s conclusion that the Fell Pony breed contains good maternal diversity that needs to be retained. It made me wonder what mare lines we have that are most in need of conservation. When I started trying to answer that question, it quickly became clear that it’s a big project, so this is just part one!
Where to Start?
To begin with I needed to decide how far back to look. I decided roughly four to five generations or around 1980. This date puts me after the Inspection Scheme mares were born, so I would have parentage information for all the females foaled after that year. This date also puts me a generation or more back past ponies that are still living so I could get a feel for if we have actually lost any mare lines. I have already learned that the answer, unfortunately, is yes.
The Usual Caveats
This project of course relies on pedigrees, so the usual caveats apply. The results of this research are only as good as the pedigrees we have to work with. There are numerous reasons why they may not be complete, such as the Inspection and Grading Up Schemes. And human error means that honest mistakes are made. We also know that some pedigree substitution has been done in the past, which has created better genetic diversity than our pedigrees say we should have. The bottom line as always is we are fortunate to have a registry, The Fell Pony Society, that tracks our registrations and pedigrees.
The venerable mare Lunesdale White Rose is well represented in the modern population. One question that needs to be answered about her line, though, is whether that's entirely through her male descendants and whether her female line is in need of conservation. I have since been informed that her female line is well represented in the breed’s population. This photo was taken in 2005.
The other thing that we have to take into account when looking at rare lines in our breed is that some lines may have become rare for a reason. Perhaps they weren’t considered proper type. Perhaps there was a temperament issue. Perhaps they didn’t have good reproductive histories. We may never know the exact reason, but long time breeders make selection decisions all the time about what lines to continue and which to let go. Preserving rare maternal lines isn’t easy!
Redhouse Dusty is another example of a Critical status mare line with a few aged but living female descendants. Photo courtesy Ruth Eastwood.
The Process
My pedigree database contains ponies who were registered worldwide from 1993-2007 and 2017-2018 and all their ancestors as far back as we know them. When I entered the 2017 and 2018 foal crops, all of the ancestors of those ponies were already entered, meaning that my dataset already contained the entire modern breeding population. In addition, my database is a useful subset of the stud books of the Fell Pony Society because it only contains, prior to 1993, ponies that contributed to the modern population instead of all ponies that were registered, some of whom have no modern descendants. For some years, my dataset is more complete than the Fell Pony Society's Grassroots database.
For this project, I am identifying mares foaled in 1980 and surrounding years. My goal is to create a list of all mares foaled in that period that contributed to the 2017 and 2018 foal crops without making the list any longer than I need to. Then I will identify if and how those mares’ lines have continued into 2017 and 2018, the most recent years for which I have worldwide data (since it takes more than 100 hours to enter a stud book into my data base, I don’t do it every year.)
The next step will of course be to see which of those 1980s-era mare lines continued into the modern population through female lines. There will obviously be mares that are well represented through their male descendants. Lunesdale White Rose is one example. She’s behind nearly half the ponies in the 2017 and 2018 foal crops, but in previous research I have done, the vast majority of that representation has been through male lines, not female. In this research project, I will find out if White Rose’s female line is in need of conservation.
Gibside Sally is an example of a Critical status mare line in need of conservation. She had just one filly foal, in 2006. That filly foal is still living and while aged, is worth considering bringing into the breeding population if possible. Photo courtesy Ruth Eastwood.
What I’ve Learned So Far
The list of 1980s-era mares I have generated so far is dividing itself into the following categories:
Lost: Mares who do not have any descendants in the modern foal crops (2006, 2007, 2017, 2018). We have lost these mare lines either because they only had male offspring or their female offspring were not retained in the breeding population. One mare in this category is Gibside Dinah, foaled in 1980, who only left one male registered descendant.
Critical: Mares who have female descendants into 2006 and 2007 but not into 2017 and 2018. These lines need to be investigated further to see if it’s possible to bring them back into the breeding population. These mare lines might be deemed Critical in the terminology of rare breeds conservation. Gibside Sally, foaled 1982, is an example of this category. She had a filly foal, Gibside Black Lace, who was foaled in 2006. Black Lace has not had any registered offspring and according to the Fell Pony Society database Grassroots is still living. At her age it could be difficult to bring her into the breeding population to continue Sally’s line, but it would be worth considering trying.
At Risk: Mares who have only one or two female descendants into 2017 and 2018. These lines need to be investigated further to ensure they aren’t lost to the breeding population. These mare lines might be deemed At Risk because they could easily drop out of the breeding population and be lost forever, reducing the maternal diversity that Dr. Winton found notable. An example of this category is Church Farm Gypsy, foaled 1982. Gypsy has a single female descendant in the modern breeding population, Raeburnhead Lexie. Lexie had a filly foal in 2016: Parcpenrhyn Maggie. It would be worth investigating whether this line can be brought back into the breeding population.
Common: Mares who have multiple female descendants into 2017 and 2018. Drybarrows Purple Heather is one example of this category with multiple female descendants in the modern breeding population.
Drybarrows Calista and Willowtrail Mayflower are descendants of the well represented Drybarrows Purple Heather mare line.
I am grateful to Dr. Winton for pointing out the need to conserve the maternal diversity in our breed, and I look forward to continuing this research project.
