Comparative efficacy of various chemical protectants on the thermostability of pigeon pox vaccine

الملخص EN

Production of live attenuated pigeon pox vaccine sustained the elevated temperatures during freeze-drying, transportation, storage and vaccination in unequipped tropical and subtropical zones is highly recommended, for this reason six protectants formulas were individually used for preparation of six pigeon pox vaccines (II-VII) beside the 1st non protected vaccine, they were lyophilized ; titrated and then tested for thermostability and thermoprotectivity to select the best stabilized vaccine ; and they were as follows : a vaccine that contain a protectant composed of (5 % lactalbumin hydrolysate : 2.5 % sucrose) in addition to four vaccines one contain trehalose instead of sucrose as 2.5 %, and the others were 2.5 %, 5 % and 10 % (Wt.

/ V.) trehalose alone and the 6th vaccine contain starch 2.5 %.

These vaccines were tested for sterility, vaccination and challenge test in susceptible squabs.

The collected blood sera were subject to serological examination for estimating the antibody response by serum neutralization test (SNT).

To test the thermal stability of different lyophilized pigeon pox vaccine formulas they were stored at -20, -4, 4, 25 and 37°C for one week.

The results proved transcendence of pigeon pox vaccine protected with 10 % & 5 % trehalose alone respectively in the thermostability and thermoprotectivey, thereby improvement vaccination efficacy in tropical and subtropical zones.