Interval feeding of protein supplement to cows on range

By: Glenn Selk, Oklahoma State University Emeritus Extension Animal Scientist

Dry, pregnant beef cows grazing low quality warm season pastures in late summer, fall, and early winter are usually supplemented with high protein supplements.  It would be desirable to feed the supplement at less frequent intervals (than daily) to reduce labor and equipment costs.

A study done at OSU in the 1990’s has indicated that cows fed the same amount of total 40% crude protein supplement either 3 or 6 days per week perform similarly.  Interestingly enough, similar research (Pope et al., 1963) was reported over 40 years ago with similar results.  Below in table 1 are the results of the 1994 experiment.  Cows were fed 21 pounds of protein cubes per week from November 17 until March 9.  From March 10 to April 22, cows were fed 28 pounds of supplement and only 17.5 pounds per week from April 23 to May 15.  Cows were provided free choice grass hay when snow or ice covered the standing forage, or when the temperature was less than 40 degrees and raining, or was less than 25 degrees at noon.  Cows were exposed to bulls for 75 days beginning May 17 and palpated for pregnancy 90 days after the breeding season.  In this trial, the cattle performance was virtually identical and was not affected by the interval at which the cows were fed the protein supplement.  Note:  Adequate amounts of standing forage or hay should be available to supply the remainder of the diet for the cows.

Table 1. Influence of supplementation interval on body weight, body condition score, and pregnancy rate of beef cows. (Wettemann and Lusby, 1994 OSU Animal Science Research Report) 

Days supplement fed per week 3 days 6 days
Number of cows 62 61
Body weight in November 1186 1210
Weight loss to April (after calving) 242 255
Body condition score in November 5.4 5.4
Body condition score in April 4.4 4.3
Pregnancy rate 98% 94%

Cattle producers that are feeding larger quantities of lower protein, high energy supplements will want to feed the supplement on a daily basis (see Oklahoma Beef Manual seventh edition chapter 21).  Too much high energy feed at one feeding may cause digestive disorders such as acidosis or founder.  The maximum recommended amount to provide during any one feeding period is one percent of body weight (example: 11 pounds for an 1100 pound cow).