Hay quality will vary due to forage type, stage of maturity at harvest and harvest conditions. In addition to hay, feeding harvested crop residue such as corn stalk bales is common. Often a combination of different quality hays are fed at the same time using past experience and some nutritional “cow sense” helping to determine the correct blend. Cow body condition and cow contentment are used as rough indicators of meeting the dry matter intake and energy needs of the cows. Evaluating the manure is a tool that can help indicate when changes in the forage mix or supplement strategy is needed. We need to be aware that the nutritional needs of the cow will change depending on production cycle.
Hay supplies are tight due to fewer hay acres and increased demand for hay in the southwest due to drought. Supply and demand dynamics have driven hay prices higher across the country. Hay quality varied greatly due to weather challenges during growing and harvest. Forage analysis is the best way to know the quality of your hay. Using average values from forage testing labs can be misleading. Dairy nutritionists will sample forages on a weekly or monthly basis. The number of dairy quality hay samples will skew the average to the high side. A recent survey of hay destined for beef cattle was conducted in northern Missouri, southeastern Iowa and northwestern Illinois. This was not a large survey but does give an indication of the wide variation in hay protein content and relative feed value (RFV).
For 17 samples the average crude protein content was 10.32% and the available crude protein was 9.41%. The available crude protein takes into account heat damaged and bound protein that is not available for digestion.
The relative feed value ranged from 61 to 106 points for an average of 81. This is an indication that many of the samples were from quite mature forage with increased fiber content. RFV will decline as fiber content increases and the more readily digestible sugars decrease.
Manure evaluation can be used to evaluate the extent of digestion. This gives an indication of forage quality and can help determine if a change in supplement strategy is needed. The ideal cow pie would have an even consistency and be uniform in size and color. The height of the cow pie should be 2-3 inches. Manure from diet containing only low protein and low RFV forage will have larger fiber particles. This is due to poor digestion in the rumen due to a lack of readily available protein and carbohydrates. Manure can be washed through a screen to show the extent of fiber digestion. However, it is more common to flatten the cow pie under your boot for further observation. For example, hay number 8 is around 6% CP and RFV of 60 points. The cow pies from cows consuming hay number 8 would be large, very firm and stack higher than desired. Nutritionally this indicates that the low protein and high fiber content is limiting digestion. A supplement strategy that brings addition protein and carbohydrate sources is needed.
Stage of production must be considered. Relying on manure scoring alone is not advisable. Hay number 1 is around 11% CP and has a RFV of 84 points. The manure may look acceptable most of the time, but during times of higher nutrient demand, such as late pregnancy and early in lactation, the change in body condition would be greater than desired. If body condition declines excessively then breed back will be delayed.
Forage sampling, manure scoring, body condition scoring, supplement strategy and “cow sense” are tools for determining the best combination of feedstuff to meet the nutrient needs of the cow herd. Optimizing the forage blend is the most economical approach and Crystalyx® Brand Supplements offers a variety of formula options to deliver additional nutrition when needed.