Studies on Some Biological Features of Trichinella Isolates

Some biological features of Trichinella from swine and dog in Heilongjiang province,China were firstly studied,the international standard Trichinella isolates,T.spiralis and T.nativa were used as the control.The experimental results indicated that development time of nurse cells around muscle larvae in mice diaphragms for 4 Trichinella isolates was different,the earliest muscle nurse cell development(encapsulation)date were at 16 days postinfection(d.p.i.)for swine isolate,at 18 d.p.i. for T.spiralis,at 20 d.p.i. for dog isolate and 22d.p.i. for T.nativa.The interval at which 100% of the muscle larvae became encapsulated was not related to the time of appearance of the first encapsulated larvae,the 100% level of encapsulation occurred at 32 d.p.i. for dog isolate and T.nativa,at 36 d.p.i. for T.spiralis and at 38 d.p.i. for swine isolate.In vitro,swine isolate and T.spiralis were more productive,with an average of total production of 55.00±7.34 and 76.2±7.57 newborn larvae(NBL) released per female worm in 24 hours of cultivation respectively,dog isolate and T.nativa had lower production,with an average of 28.8±4.30 and 22.00±3.22 NBL/female,respectively.On the basis of those results,we concluded that Trichinella from swine and dog in Heilongjiang province, China belong to Trichinella spiralis and Trichinella nativa,respectively.