Genomic Selection in Dairy Cattle Dr Wuttigrai Boonkum

Genomic Selection in Dairy Cattle Dr. Wuttigrai Boonkum

Genomic Selection • Dairy cattle most are specialised dairy breed Holstein, Jersey, Brown Swiss, Ayrshire • Some dual propose Simmental, Montbeliarde, Normande, etc • More than 80% AI from AI companies • Global exchange of genetic so international genetic evaluation

Genomic Selection P=G+E Genetic evaluation or Molecular genetics Appropriated major gene only Need time and data complete

Genomic Selection, What does it bring us? • Reliable breeding values at young age – higher success rate to get top bulls – lower costs for test proofs – shorter generation-interval

Reliability of breeding values 50% reliability is realistic

Advantages of Genomic Selection • Increased genetic improvement (30 -40%) • Higher genetic level of test sires • Higher genetic level of Delta embryo’s • Wider portfolio of commercial bulls & higher level • More outcross; less inbreeding

Disadvantages of Genomic Selection • New method, not fully proven or tested • Need to genotype a sufficiently large set of animals for accurate GEBV • Across breed accuracy low • Genotypes still costly (10, 000 bath/head)

. 3การใชระบบผสมขามพนธทเหมาะสม Table 3 Comparison of average of milk yield, reproductive performance and economic returns of Thai Friesian (TF), Thai milking zebu (TMZ) and Friebrah (FB) Dairy cattle crossbreds Traits Milk yield) kg/head/lactation( Milk yield) kg/head/day( Day in milk (day) First oestrus after calving (day) Calving interval (day) Number of service per conception (times) Income (baht/lactation) Production cost (baht/lactation) Milk production cost (baht/kg) Net profit (baht) Source: (สดใส และคณะ, 2549ก, ข) TF TMZ FB 4, 517. 76+384. 19 14. 39+2. 92 314. 45+24 69. 17+28 415. 10+72 2. 10+0. 87 52, 406. 01 29, 795. 39 6. 37 22, 610. 62 3, 902. 57+460. 91 13. 34+4. 06 292. 30+28 68. 19+43 399. 90+49 1. 70+0. 82 45, 269. 87 28, 032. 08 7. 49 17, 237. 79 2, 472. 90+456. 12 9. 20+1. 21 268. 50+51 54. 23+28 363. 70+43 1. 40+0. 69 28, 676. 24 24, 646. 17 9. 91 4, 030. 07

. 4การใชพนธศาสตรโมเลกลในการปรบปรงพนธโคนม Heritability high BLUP medium, low BLUP Traditional Selection index by MT-BLUP MAS Selection index by MA-BLUP Selection index including MA information Pre-selection by marker confirmed by MT-BLUP index Figure 6 Dairy cattle improvement using BLUP and genetic marker scheme