By Dr. Jeff Lehmkuhler
- Determine hay needs – Hay needed to overwinter a cow can be estimated relatively easily. If you know the mature weights of your cows, multiply the average weight by 3% and then by the expected number of days you will feed hay. For example, if cows at a body condition score 5 weigh 1,300 lbs, the daily hay needed would be 1,300 lb * 3%/100 = 39 lbs. Assume you began feeding hay November 15 and expect to feed until April 15, the hay needed equals daily intake in lbs X Number of months X 30 = 39 lbs X 5 months X 30 = 5,850 lbs. If bales provide 800 lbs of good forage (exclude rot/spoiled hay), the number of bales needed would be 5,850 lb /800 lb/bale = 7.3 bales/cow for the feeding period. Always add 10-20% more due to feeding losses, spoilage and longer feeding periods. Inventory hay stores in the early winter as hay will be cheaper at the start of the winter as opposed to later when hay stocks are lower.
- Match hay quality to animal needs – Use limited forage wisely by matching quality to stage of production. Growing and lactating animals have the highest nutritional needs. As you consider the annual production of a beef cow, nutritionally we tend to break them out to late gestation, early lactation, late lactation, and the dry, mid-gestation period. During late gestation, particularly the last 60-75 days before calving, the fetus is growing rapidly increasing nutrient needs of the cow. Additionally, mammary tissue development and colostrum formation require additional nutrients. As cows calve and freshen, nutritional requirements increase with milk production. Peak milk production occurs around eight weeks post-calving and corresponds with the highest nutritional needs during the production year. Nutritional needs may decrease after peak as milk production decreases. However, some research has shown that cows may sustain high levels of milk production out to 120 days post-calving. Thus, it is important to monitor cow body condition through lactation and make feeding adjustments as needed. This is important for fall calving beef cows as they may require additional supplementation to support higher levels of milk production. Feed the highest quality forage during lactation to minimize body condition loss and supplementation needs.As cows are weaned and milk production ceases, nutritional needs are greatly reduced. Dry, non-lactating cows that have weaned 6-8 month old calves should be in the second trimester of gestation. The nutritional needs to support fetal development at this point is low and corresponds to the lowest nutritional requirements for the production year. Utilize lower quality forages at this point to conserve higher quality forages for other phases of production. See the table below for guidelines on forage quality needed at different stages of production for mature beef cows. These assume cows are in good body condition and no environmental stress (i.e. mud, wet haircoats, etc…).
|Stage of Production||% TDN||% CP|
- Less Time – Limited hay stores can be stretched if you have the ability to limit the amount of time cows have access to the hay. This can only be done for mature cows that are in the dry, mid-gestational stage of production and are 5-6 body condition scores. Young and thin cows need additional feed to grow and replenish body stores and should not be limit fed.Purdue research demonstrated that limiting access to 8-12 hours did not have detrimental impacts on body weight or condition of mature cows. In this work, restricting access to hay to 8 hours reduced hay disappearance by approximately 15%. Restricting access time to hay, however, resulted in a linear decrease in body weight gain in young, second calf cows. Researchers at the University of Illinois reported findings from a similar study. Simmental cows in the last trimester were limit fed for approximately 90 days. Access time to hay in this study was ad libitum (free-choice), 9, 6 or 3 hours. Hay disappearance decreased from 34 lbs of dry matter for free-choice cows to approximately 18 lbs for cows having only 3 hours of hay access. Cow body weight gains decreased linearly as the time restriction increased. Body condition score changes followed similar trends to weight changes. In the second trial conducted hay access was restricted to only 6 or 9 hours. Again, hay disappearance decreased as access time was limited. Body weight and body condition score changes were not impacted by restricting hay access in this trial. These studies utilized above average quality grass/legume hay. The level or degree of restriction will be dependent on the quality of the forage. Low quality forage should not be restricted. Cows will need to consume as much ow quality forage as they can due to the low digestibility and low nutrient concentrations. If this management is used, the herd will need to be separated by age and production as lactating cows, late gestational and young or thin cows should not be restricted.
- Reduce feeding losses – Managing hay feeding can also aid in stretching limited hay stocks. Research demonstrated increased losses when unrolling hay on the ground. Hay is trampled into the mud from being walked and laid upon. Defecation and urination on hay will prevent intake as well. Research from North Dakota has also demonstrated that feeding with a hay processor on the ground leads to increased hay losses compared to feeding in a hay ring. Leaf shatter and small forage particle loss leads to lowered utilization. If using a processor and one wants to minimize losses, place processed hay in a feeder or bunk rather than on the ground.Hay rings should have sheeting around the bottom to minimize hay losses. Improved designs that keep bales elevated on the ground while allowing dropped hay to fall within the hay feeder also lower feeding losses. These feeders are more expensive up front but if hay is expensive, they can lower feeding costs. It is important these hay feeders are managed. If hay builds up inside the feeder and the cattle don’t consume the hay due to rot or mold, move the hay ring. If the hay is not of low quality, allow animals to consume the hay that is lying on the ground within the ring before placing a new bale in the feeder. Allowing the hay to build up to the top of the ring/sheeting/tire in these newer designs will increase losses when a new bale is offered as hay will fall out over the edge of the ring or tire. Further, placing hay rings on a feeding pad can lower losses from hay that falls outside the ring on the ground. This hay may be consumed off the ground on a feeding pad while it would otherwise be trampled into the mud around the feeder.
- Hay replacement – Replacing hay with other feedstuffs to supply the nutrients needed is feasible. A word of caution, when restricting hay the rumen will not be full. Stretch receptors on the rumen will lead to cows seeking to eat something even though nutritionally they won’t need to eat. This can lead to tree and fence damage or even cows getting out looking for something to eat. Giving access to low quality forage ad lib can curb this by giving cows something to eat and fill the rumen. Corn stover, wheat straw and other low quality forages can used.The typical fescue hay will contain 50-54% TDN and 7-9% protein on a dry matter basis. If one were to offer 1 lb of dried distillers grains, the protein supplied would be the equivalent of 3-4 lbs of hay while the energy from the distiller grains would replace 1.75 lb of hay. For dry, gestating cows soybean hulls can be used to replace average grass hay at a rate of 1.5 lbs of soyhulls per pound of hay. Cows should always be offered at least 8-10 lbs of long stemmed forage to maintain rumen health and lower the incidence of bloat. Other feedstuffs can be used to develop a low hay diet for beef cows. Be sure to work with a nutritionist to ensure the nutrient needs of the cows are met and to lower the risk of digestive disorders. Other nutrients should not be overlooked. The rumen is approximately 80% moisture and a beef cow may need 10-20 gallons of water a day. If water availability is restricted, intakes will be depressed and milk or performance will be reduced. A high quality loose mineral should be provided at all times to ensure mineral and vitamins requirements are met. If supplement is offered, considered including an ionophore such as monensin or lasalocid to improve energy efficiency. Research has demonstrated the cows will maintain similar body condition when fed 200 mg/hd/d of monensin on 5-10% less feed.
Sound management will allow you to conserve hay without sacrificing animal productivity. Remember that the animals’ nutritional needs should always come first. Work with your local county extension office or nutritionist to ensure the nutritional needs will be met. Here’s to not losing a boot in the mud.