The effects of several supplementation frequencies on forage use and the performance of beef cattle consuming dormant tallgrass prairie forage.

Abstract

Two experiments were conducted to quantify the impact on forage use and performance of varying supplementation frequency of cattle consuming forage diets across a range of frequencies. In both experiments, a common supplement was used that contained a relatively high concentration of CP (43%) and was fed at the following frequencies: 1) 2 d/wk; 2) 3 d/wk; 3) 5 d/wk; and 4) 7 d/wk. In Exp. 1, 120 Hereford x Angus cows (BW = 537 kg) grazing winter tallgrass-prairie range were supplemented at the various frequencies from December 7 until calving (average calving date = 3/7/99). All treatments provided the same quantity of supplement on a weekly basis (12.74 kg, as-fed) but divided the amount delivered on a given day equally among the number of supplementation events for that treatment. Less BW was lost from December 7 through calving (linear effect, P = 0.02) as frequency of supplementation increased, but the magnitude of difference in weight change was relatively small. Body condition responded similarly through early February (linear effect, P = 0.02), although treatment effects were not as distinct at calving (cubic effect, P = 0.11). In Exp. 2, 16 ruminally fistulated Hereford x Angus steers (BW = 257 kg) were blocked by weight and assigned to one of the four frequencies of supplementation. Steers were offered tallgrass prairie hay (73.5% NDF, 4.8% CP) ad libitum and were supplemented at a rate (relative to BW) similar to that of the cows in Exp. 1. Increasing frequency of supplementation increased (linear effect, P < or = 0.02) forage OM intake, OM and NDF digestion, and digestible OM intake. However, the most prominent differences in forage OM intake tended (cubic effect, P = 0.07) to occur with the two extreme frequencies of supplementation. In conclusion, forage use was improved with an increased frequency of supplementation, but the impact on performance is not likely to be large unless extreme differences in frequency occur.

Effects of supplementation frequency on the ruminal fermentation and enteric methane production of beef cattle grazing in tropical pastures

“…In contrast, Farmer et al (2001) provided degradableintake protein supplement 7x, 5x, 3x or 2x per week and reported that fluid passage rate responded quadratically, with the lowest rate occurring on the supplementation provided 2x per week. The infrequent supplementation of degradable-intake protein may have disrupted rumen function for a period of time, especially in the lower supplementation frequency (Bohnert et al, 2002c).…”

“…Supplementation frequency had little or no effect on VFA concentrations in comparison with daily supplementation. Similarly, other authors (Farmer et al, 2001;Currier et al, 2004;and Morais et al, 2009) have reported that two-day supplementation intervals (or shorter) had some or no effect on VFA. Morais et al (2009) observed that ruminal fermentation parameters (pH, NH 3 -N and VFA) in Nellore steers on Brachiaria brizantha pastures were stable when supplementation was reduced from seven to five or three times per week; they concluded that the maintenance of these parameters was important for adequate ruminal fermentation.…”

“…In a similar study, Morais et al (2009) also noted that the ruminal pH was not affected by the frequency of supplementation; instead, they measured higher average pH values -6.84, with a minimum of 6.5 -in Nellore steers grazing on Marandu grass and supplemented 7x, 5x and 3x per week. Likewise, Bohnert et al (2002c), Farmer et al (2001) and Beaty et al (1994) found that infrequent supplementation resulted in a lower ruminal pH compared with daily supplementation when all treated animals received supplementation, but a higher ruminal pH was observed on the days between supplementation events. In a study of the effects of supplementation frequency on ruminal fermentation in beef steers, Drewnoski and Poore (2012) observed that on the day of supplementation, the ruminal pH of steers in an alternate-day treatment (6.13) was lower (P<0.01) than those subjected to the daily-supplementation treatment (6.29).…”

BEEF SPECIES SYMPOSIUM: An assessment of the 1996 Beef NRC: Metabolizable protein supply and demand and effectiveness of model performance prediction of beef females within extensive grazing systems1,2,3

“…Köster et al (2002) indicated that inclusion of urea in supplements at less than 45% of DIP would not significantly depress performance of prepartum cows grazing dormant tall grass prairie in Kansas. Others (Beaty et al, 1994;Farmer et al, 2001) observed that infrequent (i.e., 2 to 3 times/wk vs. daily) DIP supplementation can be practiced without greatly affecting performance outcomes of winter grazing beef cows. Farmer et al (2004b) found that inclusion of NPN (30% or less of DIP concentrations) in protein supplements fed on alternative days to beef cows grazing dormant tallgrass prairie did not compromise beef cow performance.…”

Influence of Distillers Dried Grain Supplementation Frequency on Forage Digestibility and Growth Performance of Beef Cattle

“…Supplemental feeds may constitute a significant portion of variable costs of beef production, and providing protein supplements less frequently may reduce costs without negatively affecting performance (Huston et al, 1999;Farmer et al, 2001;Bohnert et al, 2002).…”