Iowa Beef Center » hay quality

Hay Making Time??

deniseschwab — Wed, 09 May 2012 13:30:15 +0000

We all know we need to make hay when the sun shines, but in a crazy year with a very early spring when should we start mowing first crop hay? ISU Extension has used the PEAQ system developed by the University of Wisconsin that takes climatic variations into account to estimate RFV of standing alfalfa to better predict when to harvest first crop.
PEAQ stands for Predictive Equations for Alfalfa Quality, and uses alfalfa stand height and maturity stage to estimate the RFV. In general, it is recommended to harvest alfalfa at about 150 RFV for milking dairy herds and 125 RFV for heifers, stocker cattle and lactating beef cattle. First crop alfalfa standing in the field can drop 3 to 5 points of RFV per day. A one-week delay of first crop harvest could cost at least 20 RFV points in feed quality.

While PEAQ provides an estimate of standing crop quality in the field, you still have to adjust for harvest loss. Under the best conditions, 10 to 20% of the forage dry matter, or about 15 RFV units for haylage, and about 25 RFV units for hay, will be lost at harvest. Therefore, to end up with 150 RFV alfalfa, it is recommended to harvest when PEAQ measurements predict 165 to 175 RFV for the standing forage.

To learn more about what PEAQ is, or to see what the PEAQ scores are for northeast Iowa, go to the PEAQ monitoring page.

What should I feed my cows?

deniseschwab — Thu, 30 Dec 2010 21:55:43 +0000

I can’t count the number of times I’ve been asked this question in the last couple weeks, and unfortunately the answer is “it depends”. It depends on the quality and quantity of forages available, the size, body condition and stage of production of the cows, the environment the cows live in, what alternative feedstuffs are available, and what options you have for feed delivery.

One of the biggest variables this year is forage quality. We are seeing very wide ranges on the energy value of hays tested through the Iowa Beef Center forage testing project. For example, the grass-legume hay samples averaged 56% TDN, but they ranged from a low of 48% to a high of 82%. If we balance for the average of the grass-legume hays we are underfeeding those cows fed the 48% TDN hay and are overfeeding the cows receiving the 82% TDN hay, and neither of those situations are good for the cow! The protein situation is also variable with the average of 13% CP but a range from 8 to 21% CP. On average these hays will meet or exceed the crude protein requirement of gestating cows; however the cows fed the 8% CP hay will need protein supplementation.

Bottom line? Test your hay to determine the nutrient content before balancing winter cow rations. Talk to your county Extension office or Extension Beef Specialist for more information or help. Then, we can balance a ration to meet your cow’s needs.

Time to test hay

deniseschwab — Tue, 26 Oct 2010 14:30:59 +0000

Now that most of the corn is in the bin, it’s time to get those forage samples taken and sent for analysis. Don’t forget that we have a program offering to cover half of the testing fee.

If you aren’t sure how to sample, check out this YouTube video featuring one of our newest ISU researchers, Mary Drewnowski.

Check with your local county Extension office or your ISU Extension Beef specialist for details on the program, materials and hay probes.

Nutritional Value of Hay in Wet Years

Sherry — Wed, 15 Jul 2009 15:21:25 +0000

With wet weather plaguing parts of Iowa during the first half of summer, we’ve heard questions regarding the expected nutritional value of hay cut for the first time in June, as well as unique storage issues associated with damp hay. Did the weather delay your first cut? If so, read on for answers to a few questions you may have.

What will the nutritional value of my hay be this winter if my first cut wasn’t until June? In an article on wet forage problems, Steve Barnhart, Iowa State University Extension agronomist, notes that the nutritive quality of a standing crop declines as it matures and is affected by spoilage miroorganisms in the high-humidity conditions, with the greatest decline in quality happening from late May to early June. The nutritive value of this hay could be fair to low, but Barnhart suggests having a sample of your forages analyzed to determine the precise feeding value. To learn more about analyzing your hay and how to use it for feed once its nutritive value has been determined, read Barnhart’s article “Wet Conditions Cause Forage Problems.”

If you’ve received an analysis of your forage sample and need assistance interpreting it, Barnhart suggests contacting an ISU Extension livestock specialist. To get you started, however, check out this eXtension article on understanding your forage analysis.

What precautions should I take when storing high moisture hay? Hay that is baled with greater than 20 percent moisture content can have a significant reduction in percent digestible protein, called “heat damaged protein.” There’s also a risk of “hot hay” if the appropriate precautions are not taken. Keep in mind the following suggestions when storing high moisture hay:

Store round bales outside individually, or in rows, only one-bale deep until heating has ceased.
Store large, rectangular bales inside, in a well ventilated area, preferably off the floor, on pallets or tires, with spaces between bales, and no deeper than one-bale depth.
Store small, rectangular bales inside, in a well ventilated area, no deeper than 4 to 6 feet deep, preferably stacked loosely with spaces between bales.

For more information on storing high moisture hay and avoiding dangerous situations with “hot hay,” check out Barnhart’s recent article on the topic.