Dept Veterinary Integrated Biosciences College of Veterinary Medicine and Biomedical Science Texas AampM University Genetic Testing of Feral Horses Testing began in early 1990s Usually at the request of an individual from a specific HMA or a private individual ID: 280414
Download Presentation The PPT/PDF document "E. Gus Cothran" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
E. Gus CothranDept. Veterinary Integrated BiosciencesCollege of Veterinary Medicine and Biomedical ScienceTexas A&M University
Genetic Testing of Feral HorsesSlide2
Testing began in early 1990s.Usually at the request of an individual from a specific HMA or a private individual.Used blood group and biochemical polymorphisms. This required taking two blood samples from every horse.Information supplied by the BLM ranged from none to herd management plans. Usually just a form like the following.Slide3Slide4
17 loci were routinely tested.Sample sizes varied but were usually between 25 to 75 animals.Standard measures of genetic variability were calculated for each herd.The values were compared to those of domestic horse breeds and to other feral herds.Slide5
N
Ho
He
Fis
Ae
TNV
15 Mile Herd 2000
29 0.4310.416-0.0372.1283315 Mile Herd 1991 47 0.3790.365-0.0381.84734White Mountain 400.3400.368 0.0772.24937McCullough Peaks 410.4050.431 0.0602.20534Green Mountain 400.3800.339-0.1201.88327Muskrat Basin 380.3740.352-0.0611.87630 Thoroughbred2650.2940.288-0.0191.78034Arabian1170.3070.327 0.0611.84638Andalusian1400.3480.362 0.0391.99344Shetland Pony 500.3680.407 0.0952.21038Welsh Pony 420.3880.387-0.0022.12747American Saddlebred2590.4040.409 0.0132.35454Peruvian Paso1410.4510.445-0.0142.50646Belgian Draft 820.4270.415-0.0282.27935 Feral Horse Mean 540.3600.351-0.0351.91330.0Standard Deviation 0.0510.053 0.1180.2466.72Domestic Horse Mean1180.3710.365-0.0142.07636.4Standard Deviation 0.0490.043 0.0650.2407.37
Genetic variability measures.Slide6
Genetic similarity and distance measures also are calculated. These are compared to the major domestic breed groups.Depending upon the State comparisons to other herds from the area or State may be done.Dendrograms are given showing similarity to domestic breeds or other feral herds from the state.Slide7
Mean S
Std
Minimum
Maximum
Light Racing and Riding Breeds
0.792
0.024
0.7440.822 Oriental and Arabian Breeds0.8000.0230.7650.844 Old World Iberian Breeds0.7970.0240.7750.816 New World Iberian Breeds0.8050.0230.7540.833 North American Gaited Breeds0.8080.0230.7710.835 Heavy Draft Breeds0.8130.0210.7510.867 True Pony Breeds0.7850.0250.7430.845Rogers’ genetic similarity of the McCullough Peaks feral horse herd to major groups of domestic horses.Slide8
+--MORGAN HORSE +----|
| | +----STANDARDBRED PACER
| +------|
- +--| +------STANDARDBRED TROTTER
| |
| | +----AMERICAN SADDLEBRED
| | +---|
| +--| +-------ROCKY MOUNTAIN HORSE | | | +-------TENNESSEE WALKER | +--| +--QUARTER HORSE | | | | | +--| +----HANOVARIAN | | | | | | | | | | +--------TRAKEHNER | | | +--| +--| | | | | | | +-----------HOLSTEIN | | | | | +--| | | | +--| | +-----THOROUGHBRED | +--| | +--| | | | +----WIELKOPOLSKI +--| | | | | | +-------SELLA FRANCAIS | | | | | | +-----KHUZESTAN ARABIAN | | | +--| | | | | | +ARABIAN | | +---| +--| | | | +---------SHAGYA ARABIAN --| | | | | +----------KURD | | | | +---------------AKHAL TEKE | +--| | | +-----------CASPIAN PONY | +--| | +-----TURKOMAN | +---------MCCULLOUGH PEAKSSlide9
SIMILARITY.76 .80 .84 .88 .92 .96 1.00
----+----+----+----+----+----+----+----+----+----+----+---+
+-------------------------- Stewart Creek
+-----|
| +-------------------------- Eagles Nest
+----|
| | +----------------------- Cooper Creek
+-| +--------| | | +----------------------- Green Mountain +--------| | | | +------------------------------------- White Mountain +--| | | | +--------------------------------------- Happy Creek Springs +-| | | | +------------------------------------------------ 15 Mile Herd +-| | | | +--------------------------------------------------- Cedar Ridge Trap | | +| +----------------------------------------------------- Tilley Creek || || +-------------------------- McCullough Peaks || +-| +|+--------------------------| +-------------------------- Whistle Creek || | || +---------------------------- Dry Creek || |+-------------------------------------------------------- Cold Springs Trap | +--------------------------------------------------------- Muskrat Basin ----+----+----+----+----+----+----+----+----+----+----+---+.76 .80 .84 .88 .92 .96 1.00Slide10
All genetic testing is now done by DNA microsatellite loci.DNA testing allows the use of pulled mane or tail hairs as samples.DNA results are analyzed in essentially the same way as blood protein data.Slide11Slide12Slide13Slide14
DNA loci give somewhat higher variability measures so are not directly comparable to protein loci.Rank levels of variation are similar.Allelic measures of diversity are more important for mSat loci.Overall DNA gives data that is as useful for population genetic analysis as blood typing.Slide15
Over 100 population analyses were made using blood protein loci.Some herds were tested more than one time.DNA testing was done on some herds analyzed using blood proteins during transitional period for lab.Have DNA data for ~180 herds, again, some tested more than once.Slide16
Burro testing is very similar to that for horses. The same mSat loci are used although not all work for burros.Only have four domestic breeds to compare to.Most burro herds show very low variability.Slide17
Population
Ho
He
Fis
Ae
TNV
Ar
Butte Valley.422.496.1482.36931.22Panamints.446.465.0412.38028.27Salin Valley.479.518.0742.50434.23 Poitou Donkey.533.515-.0362.5014237Mammouth Jack.5850602.0282.60235.37Miniature Donkey.562.623.0993.48357.40Standard Donkey.539.565.0462.90040.6.30 Domestic Mean.5393565.0462.90040.6.30 Feral Mean.397.445.1042.19830.7.20Genetic variation measures.Slide18
********************************* Poitou * * *********************** Pannaments CA
* ****
**** * *********************** Butte Valley CA
* * *****
* * * * *********************** Saline Valley CA
* * * ****
* **** * *************** Slate Range CA
* * ********* ********* * *************** Centennial Ca * * * * * ****************************** Clark Mtn. CA * * * * *********** Picacho CA * * **************** * * * *********** Chocolate Mule CA * *********** *** * *********************** Sinbad UT * * **** * * *********************** Yuma 1 AZ * * * * ********************** Minniature * * ******** ***** * ***** ********************** Standard * * * * * * * ************ ***************************** Ossabaw GA * * * * * ********************************* Cibola/Trigo 1 AZ ****************************** * * * * ********************************* Mammoth Jack * * ************** * * ********************************* Sardinian ********** * * * * ***************************** Chemehuevi CA * * ********************** *** * ***************************** Park Moab CA * * * * * ******************************************************************************* Blue Wing NV ** * ** **************************************************************************************** Wikieup AZ ** ************************************************************************************************ Kingman AZ * * * * ********************************************************************************** Seven Tanks NV ** ********** ** ********************************************************************************** East Mohave CA **** * ************************************************************************************************* Ed's Camp Az *** * * * ************************************************************************************************* Yuma 2 AZ * * * *************************************************************************************************** Havasu AZ * ***************************************************************************************************** Cibola/Trigo 2 AZ Slide19
The majority of herds have moderate to high genetic variability.This is probably due to the mixed origins of the herds.About 18% of herds have variation levels that are low enough to be of concern. Most of these are just below that level.Only about 3% have exceptionally low variation.Horse SummarySlide20
Variation is usually correlated with population size.Sometimes variation is high is small populations but this is due to recent reductions.Most herds have not shown changes in variation levels between two or more sampling periods. This is probably due to not enough time having elapsed for a change to take place.No large changes in variation level have been seen in any BLM herd to this point.