GB1077182A - Apparatus for production of virus in eggs - Google Patents

Abstract

In the propagation of virus in eggs for the production of vaccines, rows of eggs E, Fig. 3, with their broader ends uppermost are indexed stepwise in trays T and each row cf eggs, when in a stationary position, is candled for the determination of live embryos, externally sterilized, punched, inoculated, sealed, candled a second time, chopped and harvested as described in detail below. The candling stations 31 include for each egg in a row of eggs a light bulb 76 and an elastic, light-shielding bellows 80 terminating in an outwardly flared portion 81, which are drawn down on the egg; the bellows can accomodate itself to the various sizes of eggs encountered and to eggs inclined from the vertical Figs. 5 and 6 (not shown). The light 76 is de-energized when the bellows are raised. Defective eggs not containing a living embryo are differentiated by a marker 83 actuated electrically by the candling operator through a solenoid 84 and lever 85, for subsequent replacement by hand. The trays are advanced stepwise to the left upon rails 45 by pins 46 carried by a frame 47 and the frame in turn is mounted on pins <PICT:1077182/C6-C7/1> 50 which are carried on spaced-apart Fig. 4 (not shown) shafts 51 urged to the left by helical springs 52. The cyclical movement is achieved by cams 55 which raise the frame 47 and pins 46 (these engage holes in the under-portions of the trays) for movement to the left under the influence of the springs 52, and cams 60 which operate against rollers 61 fixed to the shafts 51 to move the lowered frame and pins to the right, the trays being held meanwhile by positioning pins 62. The top portion of each candled egg is individually sterilized by tincture of iodine (S, Figs. 8 and 9 - not shown). When the spraying assembly is lowered upon an egg, a sleeve (112) is urged upwardly to the right about a pivot (110) whereby a plunger (115) operates an electric switch (116) for the supply of the sterilizing liquid. The sterilized portion of the shell is punched by a tube (130, Figs. 10, 11, 19 and 20 -not shown) within which an elongated hypodermic needle (137) descends to inoculate virus suspension into the extra-embryonic fluids of the egg without itself contacting any part of the egg shell. The inoculated egg is sealed by a spray of wax emulsion (H, Fig. 12 - not shown); in this case the sensing sleeve includes a gauze screen (165) through which the sealing fluid is sprayed. After incubation, further candling and chilling, the top of the egg is chopped off by a blade (193, Figs. 14, 16 - not shown) and the severed shell portion is conveyed away by a current of air and by suction. The virus mass is sucked from the egg through a multiplicity of passages in a head (223, Fig. 17 - not shown) shaped to hold the embryo and yolk in the egg shell. Finally, the trays are overturned Fig. 13 (not shown) to dump the egg shells and remaining contents, and are then washed for further use.