Effects of supplemental feeding interval on adult cows in western Texas

Two experiments involving Brangus and Hereford x Brangus cows (3 to 10 yr) were conducted at four locations in western Texas to determine the effects of supplemental feeding interval on serum urea nitrogen (SUN) patterns, int ake of supplement and forage, and winter changes in live body weight and co ndition score. Treatments were control (Control; no supplemental feed) and the equivalent of .91 kg/d of cottonseed meal (CSM) fed daily (Daily), thre e times per week (3T/WK), or one time per week (WK). At each location, one pasture group was given all four treatments (four cows/treatment) using Cal an gates. In Exp. 1, conducted in 1994-95, blood samples were obtained for determining SUN during the last week of the study. Experiment 2, conducted in 1995-96, included both an individually fed herd and four additional herd s at each location that were group-fed the four treatments. Experiment 2 in cluded estimates of intakes of both CSM and forage in both individually fed and group-fed herds. A bolus containing chromium (Cr-bolus) was used to es timate fecal output in the individually fed cows. A double marker technique was used to determine total (Cr-bolus) and CSM (Yb) intakes in the group-f ed cows. Data included initial and final cow weights and condition scores ( Exp. I and 2), SUN patterns (Exp. 1), and supplement, forage, and total int akes (Exp. 2). Feeding CSM to range cows increased SUN concentrations (Exp. I), reduced losses in live body weight and body condition score (Exp. I an d 2), and tended to decrease forage intake by the approximate amount of the supplement (Exp. 2). Generally, providing supplement as frequently as once per week reduced losses in Live body weight and body condition score compa red with control and was as effective as once daily supplementation. For th e group-fed cows, supplement intake, forage intake, and live body weight ch ange were more variable within groups with once daily feeding than when sup plement was fed less frequently. These data indicate that feeding as infreq uently as one time per week can be effective nutrition management for adult cows grazing native range.