By Glenn Selk, Oklahoma State University Extension cattle reproduction specialist
Interval feeding of supplements has been shown to be an efficient method of feeding supplements to adult beef cows. Less is known about the use of "every other day feeding” for growing weaned replacement heifers. The objective of this University of Florida study was to examine the effects of daily versus three day/week supplementation on growth, age at puberty, estrous synchronization response, and pregnancy rates of yearling Brangus and Angus heifers consuming bermudagrass (12.9% crude protein) round bale silage.
Sixty heifers (30, Angus; 30, Brangus) were sorted by initial body weight, breed, and age and randomly allocated to 12 pens. Pens were randomly assigned to one of two treatments: 1) distillers grains and soybean meal supplemented daily; or 2) distillers grains and soybean meal supplemented three days/week. The total weekly intake of supplement was designed to be identical for both treatment groups. The heifers started at about 600 lb. and received the equivalent of about 4 lb. of distillers grains and ½ to 1 lb. of soybean meal per day. The diets were calculated to produce about 1.5 lb./day average daily gain. Supplement consumption and bermudagrass round bale silage offered were similar for both treatments.
Heifers supplemented daily had similar average daily gain as compared to heifers supplemented three days/week (1.82 vs. 1.79 lb./day). The number of heifers reaching puberty by breeding tended to be greater for daily fed heifers. Synchronized pregnancy rates and total 28 day AI pregnancy rates were also similar for both treatments. Dried distillers grains had no negative impact on the development of Brangus or Angus heifers. In this study, three days/week supplementation of developing heifers had no effect on heifer growth rates or pregnancy rates as compared to daily supplementation.
As producers look at interval or daily feeding with ethanol by-product feeds, they need to have the feed tested for sulfur content. Excessive sulfur intake may cause a toxicity called "polioencephalomalacia”. When one considers labor and fuel costs, the interval feeding protocol should be less expensive.
Source: Austin and coworkers. University of Florida 2009 Beef Research Report.