G. R. Wiggans*, L. L. M. Thornton*,1, R. R. Neitzel †, and N. Gengler ‡ * Animal Improvement Programs Laboratory, ARS, USDA, Beltsville, MD † Brown Swiss Association, Beloit, WI ‡ National Fund for Scientific Research, Brussels, Belgium and Gembloux Agricultural University, Belgium 1 Presenter: Abstract #341 Rear Legs (Rear View) for Brown Swiss and Guernsey Breeds

ADSA/ASAS Joint Meeting 2006 (2)Wiggans et al Why Rear Legs (Rear View)?  Mobility is major producer concern  Lameness is third most likely cause for culling  Not considering production  Selection could improve mobility and productive life

ADSA/ASAS Joint Meeting 2006 (3)Wiggans et al International participation  Holstein RLRV is reported from all participants but CZE and NZL  Ayrshire RLRV is reported from AUS, CAN, DEU, DFS, and NOR  Jersey RLRV is reported from AUS, CAN, DNK, ITA, NLD, ZAF  Guernsey RLRV is only reported from AUS, CAN  Brown Swiss RLRV is not included as an INTERBULL trait

ADSA/ASAS Joint Meeting 2006 (4)Wiggans et al Scoring  Brown Swiss scored on scale of 1 (low) to 9 (high)  Guernsey scored 1 to 50  Higher scores generally preferred, but extremes are not desired

ADSA/ASAS Joint Meeting 2006 (5)Wiggans et al Score Frequency 1 Brown Swiss scores multiplied by five 2 Guernsey scores grouped by fives Score for Rear Legs (Rear View) 1,2 Animals Guernsey Brown Swiss

ADSA/ASAS Joint Meeting 2006 (6)Wiggans et al Scoring cont. Trait Description Appearance of rear legsScore Perpendicular to ground, may hock out, toe in High Straight track, no hock in or out, no toe in or out Optimum Hock in, slight toe outModerate Severely hock in, toe outLow

ADSA/ASAS Joint Meeting 2006 (7)Wiggans et al Scoring cont. Hock in, toe out Correct conformation Picture credit:

ADSA/ASAS Joint Meeting 2006 (8)Wiggans et al Data 99 Unknown parent groups Sires with ≥5 daus 17,82723,353 Pedigrees including ancestors Herds 4,7497,676Cows 5,4378,503Records GuernseyBrown Swiss 1 2 birth years/group

ADSA/ASAS Joint Meeting 2006 (9)Wiggans et al Rear Legs (Rear View) Parameters Brown Swiss Standard deviation Heritability GuernseyHolstein

ADSA/ASAS Joint Meeting 2006 (10)Wiggans et al Genetic Correlation of Rear Legs (Rear View) with Linear Type Traits −0.03Dairy form Rear udder height − Udder depth Rear udder width 0.17 −0.14 − Holstein Fore udder attachment −0.08−0.19Rump angle −0.46−0.11Rear legs (side view) Thurl width Strength GuernseyBrown SwissTrait

ADSA/ASAS Joint Meeting 2006 (11)Wiggans et al Calculation of Evaluations  First: Evaluate final score & 15 linear traits with current system  Second: Evaluate rear legs (rear view)  Use only records with rear legs (rear view) in 17-trait system Allows use of correlated trait information No heterogeneous variance adjustments Only rear legs (rear view) evaluations retained

ADSA/ASAS Joint Meeting 2006 (12)Wiggans et al Cow evaluations Brown SwissGuernsey Records5,7094,749 Reliability, % Mean, PTA Minimum, PTA−1.50−2.70 Maximum, PTA Standard deviation

ADSA/ASAS Joint Meeting 2006 (13)Wiggans et al Bulls with ≥5 daughters Brown SwissGuernsey Bulls Daughters Herds Reliability, % Mean, PTA Minimum, PTA−1.20−1.70 Maximum, PTA Standard deviation

ADSA/ASAS Joint Meeting 2006 (14)Wiggans et al Further Research  Introduced in May 2006  Investigate trait inclusion in Feet & Legs Composite  Check impact on Net Merit  Second evaluation step may be unnecessary after more years of data accumulate