The effect of fertilizing forage with sodium selenate on selenium concentration of hay, drain water and serum selenium concentrations in beef heifers and calves

Abstract

. 2008. The effect of fertilizing forage with sodium selenate on selenium concentration of hay, drain water and serum selenium concentrations in beef heifers and calves. Can. J. Anim. Sci. 88: 79Á83. The objectives of this trial were to determine the effect of fertilizing grass/alfalfa pastures with sodium selenate on selenium (Se) concentration of hay, drain water and serum Se concentrations in heifers and their calves. A 9.7-ha grass alfalfa hay field was split into four strips, two of which were fertilized with 10g Se ha . Thirty-six first calf heifers in the third trimester of gestation were assigned randomly to one of nine pens and pens were assigned randomly to one of three treatments in a completely random design. Treatments were: (1) a basal diet of Se fertilized hay and a mineral mix containing 180 mg Se kg(1 ('Se hay 'Se mineral), (2) a basal diet of Se fertilized hay and a mineral mix containing no Se ('Se hay (Se mineral), and (3) a basal diet of non-Se fertilized hay and a mineral mix containing 180 mg Se kg(1 ( (Se hay 'Se mineral). Blood samples were collected via coccygeal venipuncture at the initiation of the trial and at calving. Twelve hours after birth a blood sample was collected from each calf via jugular venipuncture. Selenium fertilization increased (PB0.05) Se concentration in the hay 12-fold in the first cutting and fourfold in the second cutting. Selenium was only detectable in the drain water 1 mo after fertilization (0.55 mg Se kg(1 ). Intake of Se was greatest (PB0.05) for 'Se hay 'Se mineral heifers, intermediate for (Se hay 'Se mineral heifers, and lowest for 'Se hay (Se mineral heifers. Serum Se concentration of heifers was greater (PB0.05) in 'Se hay 'Se mineral than in 'Se hay (Se mineral heifers. Serum Se concentration of calves was higher (PB0.05) in the 'Se hay 'Se mineral, intermediate in 'Se hay (Se mineral calves, and lowest in (Se hay 'Se mineral calves. Fertilization with sodium selenate can be used as an alternative method to provide Se to beef cattle in geographic regions where Se supplementation is required.

Selenium in higher plants: understanding mechanisms for biofortification and phytoremediation

“…increasing Se concentration in food through Se fertilization) has been proposed and practiced widely for various crops and countries [47][48][49][50], the inter-and intra-specific variation in plant Se concentrations could also be explored for biofortifying food to improve human Se nutrition [51]; this approach is generally termed 'genetic biofortification' [52]. Selecting existing cultivars for high Se in the edible parts of a given crop can have immediate impact on consumers' dietary Se intake, and high-Se cultivars can be used in breeding programs to transfer the high-Se QTLs to highyielding and locally adapted cultivars.…”