Effect of inorganic or organic selenium supplementation during gestation and lactation on cow and pre-weaning calf performance

Wednesday, July 23, 2014: 3:45 PM
2103A (Kansas City Convention Center)
Chris R Muegge , Purdue University, West Lafayette, IN
Kristen M. Brennan , Alltech Inc., Nicholasville, KY
Ronald P. Lemenager , Purdue University, West Lafayette, IN
Jon P. Schoonmaker , Purdue University, West Lafayette, IN
Abstract Text:

Angus x Simmental cows (n = 48, BW = 594 kg, BCS = 5.26, Age = 2.7), pregnant with male fetuses, were used to determine the effect of selenium (Se) source during the last 80 d of gestation and first 105 d of lactation on cow and calf performance. At 203 d in gestation, cows were allotted to 1 of 3 treatments based on body weight, breed composition, and calf sire: no Se, organic Se, or inorganic Selenium. Diets contained corn silage, corn stover, haylage, dried distiller grains solubles, and mineral and were formulated to contain 10.4% CP and 0.90 Mcal/kg NEg during gestation and 12.1% CP and 1.01 Mcal/kg NEg during lactation. Diets were fed daily as a total mixed ration and none, 0.30 mg/kg Se as sodium selenite, or 0.30 mg/kg Se as Sel-Plex ®were top-dressed daily. Treatment diets were fed through 105 d post-partum (DPP). At 105 DPP cow-calf pairs were commingled until weaning at 210 DPP. At 68 DPP milk production was calculated using the weigh-suckle-weigh procedure and a milk sample was collected to determine composition. Cow weight and BCS and calf birth weight did not differ at the beginning of the trial (P ≥ 0.55). Cow BW and BCS (P ≥ 0.85) did not differ between treatments at any time point during the study.  Milk production, milk fat %, and total solids % (P ≥ .38) did not differ among treatments. Milk protein % tended to increase in the inorganic Se diet compared to organic Se diet (P = 0.07) and milk lactose % tended to be greatest in the organic Se cows (P = 0.10).  Conception to AI and overall pregnancy rates did not differ between the diets (P ≥ 0.39). Calf weights and ADG did not differ for the 105 d experimental period (P ≥ 0.77) or for the entire pre-weaning period (P≥ 0.33).  In conclusion, dietary Se source did not affect cow performance, milk production, or reproductive ability. Organic Se decreased milk protein and increased milk lactose, but did not alter pre-weaning performance of the progeny.

Keywords: beef, cow/calf, selenium