1. Animal Genetic Improvement in Tropical Area Asst.Dr. Wuttigrai Boonkum Department of Animal Science, Faculty of Agriculture Khon Kaen University

2. Why is heat stress important ? The Tropics HOT, HOTTER Temperatures have risen more in the Arctic than in the tropics.

3. Why is heat stress important ? well-being low fertility die low feed intake low milk yield

4. Economic losses Economic impacts of heat wave on dairy industry about $1 Billion 2003 economic loss $897 to $1500 million in US 2006 California heat wave kills 16,500 dairy cows statewide >2,000 cattle died in Nebraska during June 2009 2002 to 2007, Summer was the seasons with the highest of dairy deaths (15,773) in Italy

5. How heat stress occur ? Cold stress Heat stress Thermoneutral zone Heat production Ambient temperature 4-24 o C Lower critical temp. Upper critical temp. humidity

6. Heat stress effects THI > 72 for production and around 68 for reproduction are considered to indicate heat stress in dairy cattle

7. How heat stress occur ? pantingsweatingrespirationfeed intakeruminationwater intake

8. How to reduce the effects of heat stress ? adjustment of housing and facilities adjustment of housing and facilities Feed and Feeding management Feed and Feeding management Crossbreeding system x B.indicus B.taurus Production traits

9. How to reduce the effects of heat stress ? avoiding breeding during hot conditions avoiding breeding during hot conditions estrus synchronization timed artificial insemination timed artificial insemination Fertility traits

10. Alternative method Housing and Shading management Housing and Shading management Feed and Feeding management Feed and Feeding management Crossbreeding system x B.indicus B.taurus Temporary/non sustainable Production traits avoiding breeding during hot season avoiding breeding during hot season estrus synchronization timed artificial insemination timed artificial insemination Fertility traits Temporary/non sustainable Genetic selection 

11. What traits are interest to study? Using regular monthly milk records THI information at the collecting date Ravagnolo and Misztal, (2000) Using days open records Genetic selection How heat stress affect on genetic ?

12. Heat stress in Thailand Stress all time

13. Results: Determination of heat stress threshold

14. Publication

15. Results: LSM and HI for DO summer winter

16. ปัจจัยที่สัมพันธ์ต่อการเกิด ความเครียดเนื่องจากร้อนในโคนม Length of exposure to heat stress Level of production Stage of lactation Cooling management Feed consumption Feed offered Breed cattle species Size of the animal

17. National genetic evaluation under hot-humid climates of Thailand Department of Animal Science, Faculty of Agriculture, Khon Kaen University Implications : Estimated breeding value; EBV THI Threshold point Best genetic performance for milk production under heat stress conditions

18. Ent1 Ent2 Genetic effect Animal 1 Animal 2 Ent1 Ent2 Genetic effect Animal 1 Animal 2 No G x E interaction Reranking G x E interaction Ent1 Ent2 Genetic effect Animal 1 Animal 2 Scaling G x E interaction

19. Conclusions

20. ค่า EBV ของพ่อพันธุ์โคนมของกรมปศุสัตว์ปี 2553