The effect of vitamin E, selenium, and copper supplementation preweaning on the performance and immune response of beef calves

Two experiments were conducted to determine the effect of vitamin E, selenium, and copper supplementation on the preand postweaning performance, immune responses, and serum metabolites o f crossbred beef calves. In experiment 1, 71 calves were blocked by weight and allotted to one of four individually fed treatments: 1) control supplement (2 lb grain creep ) (CS), 2) CS + .27 mg selenium + 500 IU vitamin E, 3) CS + 9.1 mg copper, and 4) combination of treatments 2 and 3. In experiment 2, 80 crossbred beef calves were blocked by weight and allotted to 5 individually fed treatments: 1) control supplement (2 lb grain creep) (CS), 2) CS + .27 mg selenium, 3) CS + .27 mg selenium + 500 IU vitamin E, 4) CS + .27 mg selenium + 1000 IU vitamin E, and 5) CS + .27mg selenium + 1500 IU vitamin E. Supplements were fed daily on an individual basis. In experiment 1, vitamin E supplementation reduced plasma haptoglobin levels by the end of the study and tended (P=.11) to improve postweaning gain. However, no other effect was noted on calf performance or immune parameters in either experiment.


Introduction
Environmenta l and management stresses have been shown to compromise the immune system and lower disease resistance of newly weane d beef calves.Becaus e stress caused by weaning and transportation are nearly inevitable, any management practices that reduce immunosuppressiv e consequences of physical or pathological stress could be beneficial.
The effects of vitamin E, selenium, and coppe r supplementation on immune system functio n has received a great deal of research attention.Studies have shown that deficiencies in vitamin E and selenium can depress immune function and that, when supplemented postweaning, these nutrients can improve calf performance .Preweaning supplementation of vitamin E, selenium, and copper has not been studied previously and merits attention.Thus, our goal was to evaluate the effects of preweaning vitamin E, selenium and copper supplementatio n on performance and immune function in beef calves.

Experimental Procedures
Experiment 1. Seventy-one Hereford-Angus calves (mean age = 163 days) were block ed by weight and allotted to one of four treatmen t groups; 1) control supplement (2 lb grain creep) (CS) , 2) CS + .27mg selenium + 500 IU vi tamin E, 3) CS + 9.1 mg copper, and 4) combinatio n of treatments 2 and 3. CS was 60% dry rolled corn , 25% rolled oats, 10% soybean meal, and 5% wet m olasses, fed at the rate of 2 lb/daily.Because additional copper was provided only in the creep supplements, the coppe r content of the total diet (supplement, forage, and milk) was below the recommended level of 8 to 10 ppm.For 49 days prior to weaning, calves were separ ated from their dams daily, sorted into treatment groups, and individually fed their respective diets.
At weaning, calves were separated from their dams; vaccinated (CattleMaster 4® and Ultrabac 7®, Pfizer Animal Health, Lincoln, NE); and shipped 150 miles where they were unloaded, bled, and provided water and grass hay.On the following day, cal v es were returned to the Kansas State University Beef Cattle Researc h Center, where they were revaccinated; dewormed (Safe Guard®, Hoechst Roussel, Somerville, NJ); and fed a standard feedlot receiving ration for 28 days.
Blood samples wer e collected at the start of the trial, a t weaning, postshipping, and after the growing period.These samples were analyzed for erythrocytes and total leukocyte counts, whole blood hematocrit, hemoglobin, haptoglobin , lymphocyte blastogenic response, and IBR/BVD antibody titers.Haptoglobin, which is an acute phase protein, is gaining acceptance as an indicat or of health problems in cattle.Elevated levels s erve as an early warning of infection or inflammation.
Experiment 2. Eighty Hereford-Angus calves (mean age = 167 days) were blocked by weight and allotted to one of five treatment groups; 1) control suppleme nt (2 lb grain creep) (CS), 2) CS + .27mg s elenium, 3) CS + .27mg seleniu m + 500 I U vitamin E, 4) CS + .27mg selenium + 1000 IU vitami n E, and 5) CS + .27mg selenium + 1500 IU vitamin E. The control supplement was the same as in experiment 1.For the last 53 days prior to weani ng, calves were separated from their dams daily, sorted into treatment groups, and individually fed 2 lbs of their respective diet.
At weaning, calves were separated from their dams and shipped 250 miles to a commercia l feedlot, where they were unloaded, weighed, and bled.All calves were revaccinated (CattleMaster 4 and Ultrabac 7, Lincoln, NE) and dewormed (Safe Guard, Hoechst Roussel, Somerville, NJ).Cattle were fed a series of step-up diets for the first 5 days then place d on a growing diet.Calf weights were taken at the start of the trial; at weaning; and 7, 18, and 45 days pos t weaning.All weights were taken full except on day 53 (postshipping) and day 98 (postshipping) when cattle were shrunk followin g transportation.As in experiment 1, blood samples were collected for immune parameter analysis.

Results and Discussion
Pre-and postweaning ca l f performances are shown in Tables 1 and 2. In experiment 1, feeding supplemental vitamin E and selenium tended to improve (P=.11) the p ostweaning gain of the calves.In both experiments, dietary treatmen t had no other effect on calf performanc e or immune response, and in experimen t 2, postweaning performance was not influenced by experimental dietary treatment.

Table 1 . Effect of Copper and Vitamin E Supplementation on Calf Performance in Experiment 1
a Measured days 49 to 78. b

Table 2 . Effect of Vitamin E and S elenium on Pre-and Postweaning Calf Performance in Experiment 2 a
Low, medium, an d high levels of added vitamin E are 500, 1000, and 1500 IU daily, respectively.
b Measured from the initiation of the feeding period until weaning.a Measured for 45 day post-weaning growing period.b .27mg added selenium daily.c d