author(s)
D Reka, V Thavasiappan, P Selvaraj, A Arivuchelvan, P Visha and Manju G Preedaa

abstract
A biological study was conducted to determine the effects of dietary supplementation of different levels of rare earth elements (lanthanum and cerium) on intestinal enzymes amylase, lipase and trypsin in laying hens. A total of 96 White Leghorn laying hens of 52 weeks of age were used in 8-week feeding trial. Birds were randomly allotted to three dietary treatments each with four replicates and 8 hens per replicate. Treatments consist of basal diet supplemented with 0, 250mg (lanthanum 100mg and cerium 150 mg) and 500mg/kg (lanthanum 200mg and cerium 300 mg) of rare earth elements. At the end of 60^th week, six birds per treatment were randomly selected and Sacrificed. Intestinal contents were collected in sterile vials for the enzyme activities and stored in airtight containers at -4°C. The results of this study showed that supplementation of rare earth elements (lanthanum and cerium) Significantly (P<0.05) enhanced the intestinal amylase and lipase, whereas the level of tryptic activities did not alter. Hence it was concluded that low dose of rare earth elements, the birds had a significant effect in intestinal amylase and lipase level.