| Fox is the main fur animal raised in the northern China, whose fur is the material of high-grade fur clothing. Fox fur skin is also one of the three main fur materials (mink, fox and lamb from Persia)in the world. At present, there are 0.7 million stud foxes being raised in China, and more than 2 million fur skins are provided each year. Fox is very important in special aquiculture in China. Fox( Canidac, Carnivora )is oestrous once per season and has one foetus from each pregnancy. Fox mainly feed on protein food, hence high raising cost. Besides, there have been many risks in reproductive technology as well as from unstable market price. The impedient reproductive disease is one of the obstacles that blocks the development of this industry. After the survey of tow large-scale fox farm, it has been found that the impedient reproductive disease mainly causes the vaginitis and the elndometritis, which lead to empty pregnancy and abortion. It was once thought that the quality of the feedstuff might be the cause. However, the problem still exists even if the improvement has been made with the feedstuff. After the identification of pathogeny from aborted embryo in many fox farm and the experiment of artificial infection, a new zoonsis(GVF) was discovered and was regarded as the main cause to this problem. In order to improve the profit of fur industry, protect the security of stockman and public health, also in order to make fox raisers well informed of the disease, a survey on the veterinary epidemiology and its harmfulness is urgent and helpful so that preventive measures can be taken on the fox raising farm in China. The research and study of this paper falls into three parts: 1.Investigation of its epidemic; 2.Analysis in the laboratory;3.Experiment on the preventive studies. Above all, we investigated the serm(used RoseBengal plate agglutination test of GVF) ,the rate of empty and abortion about 1203 fox in two large scale fox-farm in Yinchuan and Shenyang. The results showed: the rate of infection,empty pregnancy,abortion,death was 25.8% , 20.1% , 9% ,2.7%.respectively,It broke out during March to June,mainly in April to May. The infection rate of GVF varied under folling circumstances: Blue fox(28.5%), higher than that of silver fox(17.6%);male foxes(37.4%)were higher than female ones(24.9),the infection rate went up from 8.3% to 55.8%. When the age went up,the infection rate went up from 27.6% to 40.6%with the rise of foetus times, and even outstanding after the mating. This means that the sick fox is the infection factor. In the experiment of prevention, we used the inactived vaccine with 2420 foxes in above two fox farm. The incidence rate went down from 24.4% to 5.3% in Xuelong fox farm in Ningxia in 2000. The prevention rate was 90% in comparison with use of vaccine in 2003 and2004. Also the rate of empty pregnancy and abortion went down from 18% to 4.95% and from 8.9% to 2% respectively. Therefore it is concluded that the use of GVF inactivated vaccine is an effective way to prevent GVF.
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