Nutrition
Nutrition Articles
Do We Typically Overfeed Protein & Energy
Those farms where the season was dry are already supplementing their cows to preserve BCS. Forage quality on droughty pastures is good but the amount of forage is less than ideal. On pastures where precipitation was adequate then feeding additional nutrient through supplementation can be delayed until available forage is thin.
Using an average 1350 lb. cow grazing in October on the prairies her daily needs are about 12 Mcal of Net Energy (NE) daily and about 815 grams of protein. On current pasture conditions where the cow can eat to capacity she will be consuming more than needed for maintenance and growth so her BCS will be improving. On a grass pasture with 10% legumes her intake will be about 13 to 14 Mcal of NE and 1200 to 1300 grams of protein. As pastures growth dwindles the amount and quality of forages declines and at some point supplementing, then feeding preserved forages begins. After making an inventory list of available forages and grains a plan can be made for feeding as the nutrients available through grazing decline and the growing calf demands more. The goal is to achieve the best performance possible from the herd while producing a ration at the best cost possible using available ingredients. For those who have access to quality straw this is an important ingredient. While its nutrient levels are lower it serves as a product to dilute higher nutrient level forages. Its energy level is similar to a grass hay but is lower in protein. It is desirable to have cows coming off pasture in good shape for fall. Maintaining a BCS of 3.0 to 3.5 is easier than trying to build body condition while weather is getting colder.
From a dietary energy standpoint straw is only slightly lower than grass hay so can be used in larger amounts when the cow is gestating. Save the hay for late gestation and the transition month, month 9. Months 7 and 8 are when the growth of the calf accelerates. The growing calf demands nutrients from the cow and will send her into a negative energy balance if the ration is not adjusted to account for this. These two months need additional energy and protein and is when straw begins to be de-emphasized and quality hay enters the ration. The average gestating cow experiencing winter conditions will need about 14 to 14.5 Mcal per day of NE intake and 920 grams of protein. This intake will allow for all the nutrient needs of cow and calf and a small amount for increased body weight but not an excessive amount of either energy or protein. Free choice intake (32lb./14.6 kg) of a common type of grass legume hay would give intakes of 15 Mcal per day or more and 1750 grams of protein which is in excess of needs. Control over the feeding process helps to extend feeding days. A silage based feeding program starts with its base ingredient of barley or corn silage. Both of these are energy rich and benefit from dilution with straw to avoid over feeding nutrients during gestation months.
Finally the transition month where the cow prepares her body for calving and lactation. Note that all ingredients have an electrical charge due to elements like calcium, potassium, sulphur, sodium, etc.. If the
total charge of the ration gets too positively charged then the cow’s body may not switch to mobilization of body calcium to assist in lactation success. Keep an eye on this charge to avoid milk fever. Most ration
balancing programs track dietary cation anion balance (DCAB) for you. You can add ration balancers if needed to the mineral mix. Additionally there is a dramatic increase in need for energy and protein for lactation. Here is where the high quality hay, silage and grain are needed. This average cow once lactating needs 23.5 Mcal of NE daily and 1450 -1500 grams of protein. Testing, chopping and mixing forages gives producers the best quality ration formulated to requirements and processed to minimize sorting.
Accurately evaluating and delivering feed will give best overall results and get the most from the forage supply. Highline® makes a range of Bale Pro’s which can be equipped with a Feed Chopper™ and a Grain Tank to allow control of amounts and types of feed ingredients. A self-loading self-propelled TMR is also available. This stretches the hay supplies through more efficient use minimizing overfeeding of expensive ingredients.