Pregnancy attrition from frozen bovine embryos cloned by nuclear transplantation

Abstract

Pregnant cows were used in a 2 × 2 factorial arrangement of trace mineral (TM) source and breed to investigate the effect of prenatal and lactating TM source on colostrum and milk quality, calf serum Ig concentrations, and calf weaning BW. Angus (n = 99) and Brangus (n = 100) cows were blocked by BW, BCS, age, and stage of pregnancy (88 ± 2 d before calving) to receive either (1) inorganic minerals (ING, n = 100) with Na selenite and Co, Cu, Mn, and Zn in salt sulfate forms, or (2) organic minerals (ORG, n = 99) with Se-yeast and Co, Cu, Mn, and Zn complexed as proteinates. The TM sources were formulated to meet NRC requirements and delivered based on the manufacturer recommendations. Colostrum and milk components were not affected (P > 0.05) by TM source. Colostrum from ORG cows had greater (P < 0.001) Se and tended to have greater (P = 0.07) IgM concentrations. The ORG calves had greater (P < 0.05) serum IgA at 12 and 24 h and greater IgG 30 d after colostrum consumption than ING calves. Birth weight did not differ (P > 0.05) by TM source; however, weaning BW, ADG, and adjusted 205-d BW were greater (P ≤ 0.05) in ORG compared with ING calves. Organic TM source provided during the last trimester of pregnancy and during lactation increased cow colostrum Ig concentrations and calf absorption of IgA and IgG. Postnatal growth was improved in calves born to dams that were supplemented with organic trace minerals.