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TEAT NUMBER AND ITS RELATIONSHIP TO FEMALE REPRODUCTION TRAITS. S. Nakavisut, R. E. Crump, H.-U. Graser and S. Anothaisinthawee. Teat Number. Heritable (h 2 ~ 0.30 - 0.40) Easy to record (count) Records available at an early age Guarantee sufficient teats to nurse litters
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TEAT NUMBER AND ITS RELATIONSHIP TO FEMALE REPRODUCTION TRAITS S. Nakavisut, R. E. Crump, H.-U. Graser and S. Anothaisinthawee
Teat Number • Heritable (h2 ~ 0.30 - 0.40) • Easy to record (count) • Records available at an early age • Guarantee sufficient teats to nurse litters • “Is TN an indicator of mothering ability?”
QUESTION Do sows with teatnumber have: • Larger litters • Healthier & heavier piglets • More piglets weaned per litter • More pigs produced/sow/year
OBJECTIVE To investigate the genetic relationships between TN and female reproduction traits
Material and Methods • Combined dataset of DU, LW & LR • From 1991 to 2001from 4 government breeding centres of Thailand • 5099 F & M pigs with TN record • 3309 litters (994 sows)
Discussion • h2 for TN ~ moderate : for repro traits ~ low • rg (TN & LS traits) ~ 0 • rg (TN & LW traits) ~ very slightly positive • rp (TN & reproduction traits) ~ 0 • Agree well with previous reports
Conclusion • Teat Number is NOT a good indicator of mothering ability • Selection to increase LS is unlikely to affect TN • Selection to increase TN may also increase LW • With LS, TN could become limited & need to be selected for