The hog cholera virus.

Hog cholera virus (HCV) is a spherical enveloped particle of about 40-60 nm dia. The viral genome is a single strand RNA of about 12,000 bases with positive polarity. One single large open reading frame codes for presumably four structural, i.e. three glycoproteins and a core protein, and about three to five nonstructural proteins. The functional role is not yet fully clear for all viral proteins. HCV belongs to the pestivirus group and it is closely related to bovine viral diarrhoea and border disease viruses. The relationship extends to morphology, antigenicity, host spectrum and molecular properties. Pestiviruses hold generic status in the family Flaviviridae.     

Transmission of hog hog cholera virus by mosquitoes.

Mosquitoes trapped during an epizootic of hog cholera (HC) in Maryland in 1969 were prepared into 40 pools which were inoculated in pigs. Hog cholera virus was confirmed in pigs inoculated with 8 of 40 pools of mosquitoes. Generally, the pigs contracting HC developed chronic infections with persistent viremia that lasted 30 or more days. Two pigs seemed healthy when euthatized 62 and 80 days after inoculation, yet viremia of high titer was detected in each. Experimental studies were performed with 2 laboratory strains of mosquitoes, Aedes aegypti and Culex tarsalis, to determine if biological and mechanical transmission occur. Biological transmission was not confirmed, but HC virus was retained in A aegypti for 3 days. Mechanical transmission was confirmed with A aegypti in 2 of 9 experiments.     

Thermal inactivation of hog cholera virus in ham.

Experiments were conducted to determine the temperatures required to inactivate hog cholera virus (HCV) in fresh ham after 1 minute and in cured and processed (canned) ham after 90 minutes. A momentary or "flash" temperature of 71 C for 1 minute caused inactivation of the virus in 15 of 15 cubes (2 cm3) of ham. Hog cholera virus was destroyed in 21 of 21 canned hams (weighing 0.91 kg each) when an internal temperature of 65 C was sustained for 90 minutes. Pigs were found to be more sensitive than tissue culture cells for detecting viable HCV in heat-processed fresh hams. Virus was isolated by tissue culture technique only from those hams exposed to temperatures below 61 C. The relative concentration of HCV in unheated cured hams of experimentally infected pigs varied over a wide range; these pigs were inoculated with the virulent Ames strain and were killed on postinfection day 6 or 7.     

Stabilization of hog cholera virus by dimethyl sulfoxide.

The stability of hog cholera virus through five freeze-thaw cycles in the presence and absence of dimethyl sulfoxide was studied. In the absence of dimethyl sulfoxide the hog cholera virus titer was reduced 52% to 91% following successive freezing and thawing cycles. However, when dimethyl sulfoxide was added to the viral suspension the virus titer appeared to remain the same after the same number of freezing and thawing cycles.     

达康灭毒灵对猪瘟病毒的杀灭试验

采用直接荧光法进行了达康灭毒灵对猪瘟病毒的杀灭效果试验.分别将有效氯浓度为100 mg/L和50 mg/L的达康灭毒灵消毒液与含有104 FA-TCID50猪瘟病毒Thiverval株病毒液的混合物于20 ℃水浴作用10 min和20 min,均可以完全将病毒杀灭.