| Traditionally, the piglets is castrated at 1 week after birth, the purpose is to remove the bad odor in the pork, named the boar taint. This kind of peculiar smell is higher incidence in the pork of maturity boars, and this will decrease the meat quality. We can eliminate the boar taint by castration, increase the fat amount in the muscle, improve the meat quality, but the growth and the feed efficiency of the castrated boar is less than the intact boar, the back fat is thicker, EU countries will ban the castration in the pigs by the end of 2018, which may set invisible barrier in the global trade. After many years study, scientists de-velop the castration vaccine-Improvac which can not only use the benefits of castration but also retain the natural growth advantage of the boar, as a vaccine to control of boar taint, Improvac is developed by Pfizer and spread to the world. This study mainly shows the ef-fect of Improvac to control the boar taint, growth performance and carcass quality of boars, and provide the evidence for using in Chinese pig industry.We divided all the 240 pigs into 4 groups in the first trial, the first group is Castration, the 2nd and the 3rd are Improvac, and the 4th is intact boars, collect the blood and then separate the serum 1 day before the 1st injection and slaughter, and detect the antibody lev-el of testicle steroids and GnRF, measure the width of the two testis, and assay the concen-tration of androstenone and skatole in the belly fat collected 30g from carcass. The result indicate that the boar taint is controlled in the two Improvac groups, the skatole and an-drostenone are all decreased and is less than the threshold.We select total 80 boars in the 2nd trial and split all the boars into two groups equally, Improvac and Castration, record the feed intake and bodyweight of all the phase include the weaning,1st vaccination,2nd vaccination and slaughter. The result shows that the average bodyweight of Improvac pig is more than Castration 6.28 kg, the FCR of Improvac group is 2.65, which is less than the 3.03 of Castration by 0.38, the culling rate is 7.50% and 10.00%, it is decreased by 2.5% in the Improvac pig, and the total feed intake is less than Castration up to 928.04kg, the average feed intake is decreased by 20.20kg, the ADG of the Improvac pig is increased by 0.028kg,0.021kg and 0.051kg, the improvement rate is 5.56%,3.43% and 9.84%. This study shows that Improvac pig can improve ADG, decrease feed intake and culling rate, increase the bodyweight of slaughter.The 3rd trial is conducted in the 1st farm of COFCO in Wuhan, the duration is up to 236 days, there are 8 pens in each group of Improvac and Castration, and there has 18-19 pigs in each pen. The result is similar as the 2nd trial.There are total 300 pigs is divided equally into the two groups by birthday weight in the 4th trial, Improvac and Castration, the pigs is split randomly into 16 pens, reared by Ad lib and record the growth and feed intake from the weaning to the slaughter, slaughter 107 Impropigs and 105 Castration pigs in the slaughterhouse in the final, measure and record the meat character and carcass data. The result shows that the dressing percent of Impropigs is bigger than Castration by 0.04%, the back fat at the 6-7th rib of the Impropig is decreased by 0.18cm significantly(0.01<P<0.05),and the back fat at the last rib is decreased by 0.22cm significantly(P<0.01).After analyzing by synthesis the above results, we can see that it can eliminate effi-ciently the boar taint, improve the feed conversion rate and growth performance, improve the meat quality by using Improvac, indicating that we can spread the using of this product in China market. |
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