Longitudinal Analysis of Somatic Cell Count for Joint Genetic Evaluation of Mastitis and Recovery Liability

• Better models of genetic evaluation for mastitis can be developed through longitudinal analysis of somatic cell count (SCC) which usually is used as a proxy for mastitis. Mastitis and recovery data with weekly observations of SCC were simulated for daughter groups of 60 and 240 per sire. Data were created to define cases: 1 if SCC was above a pre-specified boundary, else 0. A transition from below to above the boundary indicates probability to contract mastitis, and the other way indicates recovery. The MCMCglmm package was used to estimate breeding values. In the 60 daughters group, accuracies ranged from 0.53 to 0.54 for mastitis and 0.22 to 0.23 for recovery. Whereas, in the 240 daughters group accuracies ranged from 0.83 to 0.85 for mastitis and 0.57 to 0.65 for recovery. Reasonable accuracies can be achieved from SCC based estimates.

Subject headings

NATURVETENSKAP  -- Matematik -- Sannolikhetsteori och statistik (hsv//swe)

NATURAL SCIENCES  -- Mathematics -- Probability Theory and Statistics (hsv//eng)

LANTBRUKSVETENSKAPER  -- Bioteknologi med applikationer på växter och djur -- Genetik och förädling inom lantbruksvetenskap (hsv//swe)

AGRICULTURAL SCIENCES  -- Agricultural Biotechnology -- Genetics and Breeding in Agricultural Sciences (hsv//eng)

Keyword

Mastitis liability

Recovery liability

Somatic cell count

Publication and Content Type

ref (subject category)

kon (subject category)