Cow-Calf Corner: How much hay do I need to feed?; 2017 beef cow herd dynamics

Dec. 11, 2017
How much hay do I need to feed?
By Glenn Selk, Oklahoma State University Emeritus Extension animal scientist
Calculating the amount of hay that is needed on both a short-term and over the course of an entire winter are mathematical exercises that are required on any cow-calf enterprise. There are scientifically based “rules-of-thumb” that can make these mathematical exercises more precise: The size of the cow, the lactation status of the cow, and the quality of the forage are key elements in determining the average daily intake of the cow. Standing forage in pastures or as crop residue can provide much of the forage needs early in the winter and when not covered by snow. As standing pasture forages diminish in both quality and quantity during the course of the winter months and most of the forage consumption comes from stored hay, then how much hay will the cow eat voluntarily? How much hay do I need to plan to feed this winter? How much hay do I need to put out for the next few days? The following forage intake table can provide a good way to estimate forage needs.
Table 1. Forage capacity of beef cows (Lalman and Richards, OSU Beef Cattle Manual, 7^th ed. pg 133)

*DM: Based on 100% Dry Matter; Intake estimates assume that adequate protein is in the diet whether from forage or supplementation.
Many grass hay samples will test 7 to 10 percent moisture. Therefore, when calculating daily hay intake on an “as-fed” basis, divide the pounds of hay intake (from Table 1) by 0.93 to 0.90 to determine actual hay intake by the cow.
Intake in forage fed to cattle is generally limited by the forage capacity of the digestive tract. Forage intake is correlated with forage quality as shown in the table above. The more rapid rate of digestion and passage of higher quality forage results in considerably higher dry matter intake compared to lower quality forage that is lower in digestibility.
Lactation represents the greatest need for additional energy beyond that needed for maintenance. An average milking beef cow requires 50 percent more TDN or energy than she does when dry. It should be noted that lactating cows consume more forage compared to gestating cows due to the increased energy demand.
Large cows will require more energy than will small cows. Therefore the hay or forage requirements are calculated based on a percentage of the body weight of the cow. Be honest with yourself as you estimate cow size and therefore hay amounts that are needed.
These estimates do not include hay wastage. Feeding method and hay quality will affect the percentage of the hay that is wasted. Estimates of about 6 to 11 percent hay wastage been reported when large round bales were fed in bale ring feeders.
Therefore, when we evaluate the amount of hay to haul to the pastures and put in bale rings we need to make the entire calculation. Let’s assume that we have an average of 1200 pound non-lactating, pregnant cows, that after calving and a short recovery will weigh 1150 pounds while lactating. The dry cow will consume 26.4 pounds/day of average quality grass hay on a 100 percent dry matter basis. However, the hay is actually 90 percent dry matter which means that the cow will consume 29.3 pounds on an “as-fed” basis. If our hay feeding in the bale rings is very efficient and we lose only 6 percent as hay wastage, then we need to haul 33.98 pounds of hay per day per cow to the pasture. After these cows have calved, (using the same calculations but for lactating cows) we would need to haul 35.48 pounds per cow per day of the same hay. These calculations assume that very little, if any, standing forage is available to be consumed. Depending on quality and quantity, standing forage could reduce the hay intake significantly.

2017 beef cow herd dynamics
by Derrell S. Peel, Oklahoma State University Extension livestock marketing specialist
The beef cow herd began recent expansion in 2014 growing 0.75 percent followed by more significant growth in 2015 (2.95 percent) and in 2016 (3.46 percent). From the January 2014 low of 29.1 million head, the herd has expanded by 2.1 million head to the January 2017 level of 31.2 million head. There are numerous indicators that herd expansion continued in 2017. The answer will come with the Cattle report issued by USDA-NASS in late January.
The potential for herd growth starts with available replacement heifers. On Jan. 1, 2017, 6.4 million replacement heifers were reported, representing 20.6 percent of the beef cow inventory. This was the third largest replacement heifer percentage, down just slightly from the two prior years. Of the total replacement heifers, 4.0 million were expected to calve in 2017. This was a record number of reported heifers calving since this data became available in 2001. These numbers confirm the considerable potential for herd expansion and indicated producer intentions to continue adding to cow inventories. The question is whether producers have adjusted their intentions during the year. Open replacement heifers can be easily diverted into feeder markets if producers’ expectations have changed.
Changes in the beef cow herd are a function of the pace of heifer retention relative to the pace of cull cow slaughter. Heifer slaughter provides a delayed indication of heifer retention. Year-to-date heifer slaughter through late November was up 12.3 percent year over year. This follows from the jump in quarterly heifers on feed, up 10.6 percent in July and 13.0 percent year over year in October. However, even with the increase in heifer slaughter, the ratio of steer to heifer slaughter remains well above historical levels. Heifer slaughter was squeezed dramatically in 2015 and 2016 and, although it is increasing, has yet to return to normal levels relative to steer slaughter.
Beef cow slaughter is up 10.1 percent in 2017 through late November. This follows a 13.7 percent year over year increase in cow slaughter in 2016. Part of the increase in cow slaughter is simply due to herd growth since 2014. However, like heifer slaughter, beef cow slaughter was sharply reduced in 2014-2016 as a part of jumpstarting herd expansion. Net beef cow culling was a record low 7.6 percent in 2015. Sustained below-average culling rates in 2014-2016 were possible following above average culling rates from 2008-2013, including drought-forced liquidation that removed many older cows, and allowed a period of reduced culling as herd expansion began. If the current beef cow slaughter pace continues through the end of the year, the 2017 beef cow culling rate will be 9.0 percent, still below but close to the long-term average of 9.6 percent. In other words, the industry is returning to normal beef cow culling rates. Both heifer and beef cow slaughter are consistent with continued but slowing herd expansion.
There seems little doubt that herd expansion continued in 2017, albeit at a slower pace than 2016. The jump in heifer and beef cow slaughter both reflect a return to more typical relative slaughter rates. I am currently estimating that the 2018 beef cow herd will be up 1.5-2.0 percent over January 2017. Expansion rates above or below this level are possible, though expansion above 2.5 percent is difficult to reconcile with current numbers. Expansion slower than 1.5 percent is, of course, possible but it would suggest that an unusually large percentage of pregnant heifers available on Jan. 1 did not, in fact, enter the herd. This begs the question of what happened to them in that situation. The annual cattle inventory numbers in the January report are eagerly anticipated, not only to confirm what happened to the beef cow herd in 2017 but for indications of what lies ahead in 2018.
Cow-Calf Corner is a newsletter from the Oklahoma Cooperative Extension Agency.