ABSTRACT The present study was carried out to investigate the effect of dietary supplementation with vitamin E and stocking density on the mortality, body weight gain, feed conversion ratio, European production efficiency factor, heterophil/lymphocyte (H/L) ratio and liver glutathione (GSH) and malondialdehyde (MDA) levels of broilers. In total, 570 one-day-old Vencobb 400 broiler chickens were randomly assigned to three treatments, with six replicates each. G1 served as normal control and birds were provided a normal floor space (0.0465 m2/bird from day 1 to 21 and 0.0929 m2/bird from day 22 to 42) and basal diet containing vitamin E at 70 g/ton feed (n=150). G2 and G3 birds were subjected to high stocking density (0.0279 m2/bird from day 1 to 21 and 0.0557 m2/bird from day 22 to 42). G2 served as the high stocking density (HSD) control, birds were offered a basal diet with no vitamin E (n=210), whereas G3 birds were fed a basal diet containing vitamin E at 70 g/ton feed (n=210). The birds were fed with feed and water ad libitum throughout the study period. The supplementation of vitamin E to the birds subjected to HSD had a positive effect on body weight gain, feed conversion ratio (FCR), European Production Efficiency Factor (EPEF), H/L ratio, and liver GSH and MDA levels with those subjected to HSD and not supplemented with vitamin E. The results of the present study indicate that the supplementation of vitamin E at 70g/ton of feed to broilers subjected to HSD could effectively reverse the negative effects of HSD, and improve broiler performance.

Successful resource development for a marine placer gold deposit requires continuous sampling throughout the life of mine. The cost of sampling marine placer gold deposits is exponentially more expensive than for terrestrial placer and non-placer gold deposits and thus warrants a comprehensive cost-effective sampling strategy. The optimum sample support size depends on expected gold grade, desired confidence limit, and shape and size of the gold grains. The optimum sample spacing depends on the continuity of the deposit, required confidence limit, and cost-benefit analysis of a sampling programme. The current study combines sample support size and spacing determination for resource development of a marine placer gold deposit. The study used two methods to calculate the sample support size - modified Gy's formula and the approach pioneered by Clifton et al. (1969). Using historical drillhole data, a geostatistical simulation of a representative geological/mineralization domain was created on an extremely dense grid. The simulation realizations were validated using statistical, spatial, and graphical methods. Additional sample support sizes were then created by combining adjacent simulation nodes to form double, quadruple, and octuplet multiples of drill diameter sizes. The simulations were sampled at three different spacings: 100 m x 100 m; 50 m x 50 m; and 25 m x 25 m and then each sample set estimated into 50 m x 50 m blocks with ordinary kriging. A comparison between the actual and estimated block results was then carried out and the confidence of each sampling pattern (sample spacing and sample support size) determined. A cost-benefit analysis was then used to determine the optimum sampling strategy for the marine placer gold deposit.