Research On The Breeding Measures Of The Growth Rate And Body Appearance For The Large White

According to our country swine genetic prediction project requirement, the Large White swinery from Baoding agricultural animal husbandry company as the breeding object of study, the performance were measured by the animal model BLUP(best linear unbiased prediction)and relative software GBS, establish and improve the breeding system of boar in the farm, which including the register, breeding process, performance measurement, genetic prediction, breeding matching measures and so on. Improved the growth rate and reproductive performance of the Large White as the main breeding goal, at the same time, strengthened the choice of body appearance, especially the compactness of foot and limb, and finally, increased the overall production performance of the Large White.The individual number of performance measurement in this experiment were 276, including 47 boars and 229 sows, selected and remained 156 which including 14 boars and 142 sows, finally. The breeding of seed rate and selection intensity was 29.79%, 62.00% and 1.159, 0.644.Compared with the sow at the same term in the farm, the reproductive performance of core group zero generation, which including the total number born, the number born alive and the born litter weight were increased 0.50 heads, 0.52 heads and 1.91 kg, respectively.The growth rate and body appearance of core group one generation had a certain extent improved through one year measurement and selection. Compared with the replacement gilt, the weight of 21 days about the boar and sow of the core group one generation were increased 0.03kg and 0.13kg, respectively,the Large White of the days to 100kg shortened 1.41 days and 3.67 days in phenotype and 0.07 days and 0.16 days in genetics respectively, the average daily gain of 30～100kg increased 16.22g and 21.82g,respectively. The backfat thickness of sow to 100kg of body weight were phenotypically reduced by 0.5mm and were genetically reduced 0.63mm ,respectively, the same index on the boar was not improved greatly in phenotype, but reduced 0.5mm in in genetics.The estimate breeding value of days to 100kg and backfat thickness of one generation core group boars was superior to the replacement boar at the same term, the lowest and highest estimate breeding value of the replacement boar was -0.533, 3.73 and -3.99, 3.78, which was 60.07%, 184.52% and 91.00%, 2.38% higher than the core group, respectively. The estimate breeding value of days to 100kg and backfat thickness of one generation core group sows was superior to the replacement sow at the same term, the lowest and highest estimate breeding value of the replacement sow was 46.40%, 56.08% and 9.38%, 39.59% higher than the core group, respectively. The inbreeding degree was controlled well and the population inbreeding coefficients was 0.036.The body measurement data of the boar was not improved obviously, the body measurement index of sow was higher than replacement gilts, it showed that, the growth and development was well, the body structures was well-balanced.From one year measurement and analysis, we can draw a conclusion that, compared with the same term replacement boar, the growth rate of core group showed certain advantages, but the improvement of body appearance was lower, the breeding work afterward should be strengthened. The higher breeding of seed rate and lower selection intensity lead to the lower genetic progress. The best equilibrium point of breeding of seed rate allowabled by the selection intensity and physical production should be explored in the later breeding work.