SERO-PREVALENCE OF INFECTIOUS BRONCHITIS IN CHICKEN IN BANGLADESH

The investigation was conducted to detect infectious bronchitis (IB) virus-specific antibody in chicken from some selected areas of Bangladesh. The indirect enzyme linked immunosorbent assay (iELISA) was performed to estimate the infectious bronchitis virus specific antibody. In case of sera-samples collected from BRAC diagnostic laboratory, Gazipur, 100% sera samples were found to be positive to IBV; the highest antibody titres were recorded as 9867.29. The average antibody titre of samples from Anis Poultry Farm, Pabna and farms driven by beneficiary of SDC, Faridpur and layer chickens reared with the help of BEES, Hobigonj were recorded as 1234.38, 1076.94 and 4572.85 and percent of sero-positive cases were 56.67%, 43.33% and 92.50% respectively. In this study all breeds of chicken (non descriptive indigenous and commercial) and age groups were found equally susceptible to IB.

Red drop in the quantum yield of fluorescence of sonicated algae

The change of the quantum yield of fluorescence, Phi, with the frequency of exciting light, was investigated in Chlorella, Anacystis, and Porphyridium suspensions, and in sonicates from these cells prepared under aerobic and anaerobic conditions. In case of Chlorella, sonicates were made in acid and in alkaline media (pH 4.65 and 7.80). In the alkaline medium, a drop of Phi towards the longer waves was found to begin at 1.466 x 10(4) cm(-1) (682 nm) in sonicates, and in suspension. In the acid medium, the drop began at 1.471 x 10(4) cm(-1) (680 nm), 1.418 x 10(4) cm(-1) (705 nm), and 1.389 x 10(4) cm(-1) (720 nm) in suspension, anaerobic sonicate, and aerobic sonicate, respectively. The results indicate that the cause of the change in the red drop is preferential destruction of a long-wave component of chlorophyll a (such as Chl a 693). The amount of this component remaining after sonication is larger in alkaline than in acid sonicates. With Anacystis and Porphyridium, only alkaline suspensions (pH 7.80) could be used for sonication, because in acid medium, the phycobilin-chlorophyll complex is rapidly broken and phycobilin extracted from the cell. In Anacystis, the red drop begins at 1.562 x 10(4) cm(-1) (640 nm) and 1.538 x 10(4) cm(-1) (650 nm) in suspension and sonicate, respectively; in Porphyridium, it starts at 1.550 x 10(4) cm(-1) (645 nm) in both cases. These results suggest that sonication in alkaline medium (pH 7.80) destroys some Chl a 693 in Anacystis, but not in Porphyridium.

Sterilization of Culex pipiens fatigans Wiedemann by apholate

The use of alkylating agents has been found to be a promising way of chemosterilizing mosquitos for control purposes. The investigation discussed in the present paper has shown that apholate (2,2,4,4,6,6-hexahydro-2,2,4,4,6,6-hexakis (1-aziridinyl)-1,3,5,2,4,6-triazatriphosphorine) can induce sterility rates of from 43% to 95% in Culex pipiens fatigans Wiedemann treated in the larval stage, and from 80% to 100% in C. fatigans treated in the adult stage; treatment in the pupal stage produced no significant sterility.Of the methods of application of the apholate tested (immersion of larvae and pupae in water containing apholate, exposure of anaesthetized adults to residual deposits of apholate and dusting of anaesthetized adults with apholate powder), the dusting method was found to be effective.Apholate induces sterility in both sexes. Females were affected much more when they were treated in the adult stage. The average number of eggs laid by a treated female was found to be reduced no matter whether the treatment was during the larval or the adult phase.Male mosquitos chemosterilized by dusting were more competitive than normal males.