Screening of pigmented Bacillus aquimaris SH6 from the intestinal tracts of shrimp to develop a novel feed supplement for shrimp.

AIMS: To develop a novel feed supplement for shrimp using pigmented spore-forming bacterial strains isolated from their gastrointestinal tracts. METHODS AND RESULTS: Eight pigmented Bacillus strains were selected from the isolates based on high production of heat-stable spores, typical UV-Vis spectra of produced carotenoids (400-550 nm), and free radical scavenging activity of their extracts. Of the eight strains, the red-orange pigmented Bacillus aquimaris SH6 was selected because it showed the highest abundance in shrimp guts (70% population). Whiteleg shrimp (n = 30 per group) fed with SH6 spores, at >3 × 106  CFU g-1  pellet for 4 weeks had redder colour (score of 21-23 vs 20-22), 2·7-fold higher astaxanthin level (0·69 vs 0·25 µg g-1 shrimp), 34% higher weight gain (7·18 vs 5·32 g shrimp-1 ), and 85% higher phenoloxidase activity (OD490  = 0·265 vs 0·143) than shrimp in the control group. CONCLUSIONS: The result supports the potential use of B. aquimaris SH6 as a feed supplement for promoting the colourization and weight gain, and for enhancing innate immunity of whiteleg shrimp. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that carotenoids produced by B. aquimaris SH6 can be successfully absorbed and converted to astaxanthin in whiteleg shrimp.

Incidence of childhood cancer in Ho Chi Minh City, Vietnam, 1995-97.

Incidence rates of childhood cancer for the city of Ho Chi Minh are presented for the first time. For the 3-year period 1995-97, a total of 302 cancer cases were registered in children under 15 years of age, with a male to female ratio of 1.1. The overall crude rate was 78.8 and the age-standardised incidence rate was 88.4 per million person-years, which was low in comparison with other countries in eastern Asia and with the predominantly white population of Australia. Leukaemia (principally acute lymphocytic), brain tumours and lymphomas were the most common childhood neoplasms, which is consistent with the pattern observed in other registries of the region. The rate of retinoblastoma was higher than in the other regional registries. On the other hand, no cases of hepatocellular carcinoma were registered.

Cancer incidence in Ho Chi Minh City, Viet Nam, 1995-1996.

The results from the population-based cancer registry for the city of Ho Chi Minh in 1995-1996 represent the first information on the incidence of cancer in southern Viet Nam. A total of 4,080 cancer cases in males and 4,338 in females were registered, corresponding to age-standardized incidence rates (ASRs) of 130.9 per 100,000 in men and 100.7 per 100,000 in women. As elsewhere in South East Asia, the principal cancer of men was liver cancer (ASR 25.3), with moderately high rates of lung cancer (ASR 24.6) and stomach cancer (ASR 16.5); cancer of the penis, reportedly very common in early case series from Viet Nam, is now rarely seen. In women, cervical cancer was the dominant malignancy (ASR 26.0) followed by breast cancer (ASR 12.2) and stomach cancer (ASR 7.5). Although there may be some under-registration in these early years of operation, the recorded rates of cervical cancer and liver cancer are already high and suggest that southern Viet Nam would benefit from an effective cervical cancer screening programme, as well as efforts to interrupt the transmission of hepatitis B virus to reduce liver cancer incidence and effective anti-smoking programs.