Abstract: This disclosure describes a modified live infectious laryngotracheitis virus (ILTV) developed from a strain of ILTV grown at a reduced incubation temperature, vaccines that include the modified live ILTV, methods for producing the live modified ILTV, and methods that include administering the modified ILTV to a subject.

Abstract: This disclosure describes a modified live infectious laryngotracheitis virus (ILTV) developed from a strain of ILTV grown at a reduced incubation temperature, vaccines that include the modified live ILTV, methods for producing the live modified ILTV, and methods that include administering the modified ILTV to a subject.

Abstract: The present invention comprises a method for microencapsulating a core material comprising the steps of a) mixing a core material with an encapsulating polymer, b) supplying a supercritical fluid capable of swelling the polymer to the mixture under a temperature and a pressure sufficient to maintain the fluid in a supercritical state, c) allowing the supercritical fluid to penetrate and liquefy the polymer while maintaining temperature and pressure sufficient to maintain the fluid in a supercritical state, and d) rapidly releasing the pressure to solidify the polymer around the core material to form a microcapsule. This method requires neither that the polymer nor core materials to be soluble in the supercritical fluid and can be used to rapidly and efficiently microencapsulate a variety of materials for a variety of applications.

Abstract: Novel live, cold-adapted temperature-sensitive (CaTs), attenuated Newcastle disease virus vaccines are provided which are effectively immunogenic and contain a mutant of a Hitchner B.sub.1 parent strain of Newcastle disease virus.

Abstract: The cold-adapted (ca) temperature-sensitive (ts) vaccine is prepared by serially passaging a suitably selected virus (e.g. Arkansas-type DPI strain) through a culture medium at a suboptimal replication temperature which is less than about 35.degree. C., e.g. 28.degree. C., and harvesting the live, cold-adapted mutant for formulation into dosage units of, for example, about 10.sup.3 to about 10.sup.5 EID.sub.50 /bird. The ca ts mutant is much less able to replicate at 40.degree.-42.degree. C. (internal avian body temperatures) than at the temperature of the bird's upper respiratory tract, which is below 40.degree. C. The vaccine can be administered by any of the usual techniques, including the spray technique. Vaccines of this invention appear to be very effective (immunogenic), but are also safe (non-pathogenic).