October and November is normally a busy time for ranchers, between weaning, cow pregnancy check, and securing fall and winter feed needs. Cow condition during this time of the year is the easiest to control as you can add protein and energy to improve condition without having to also supply added energy for the harsher winter months. When you see your cows every day, sometimes it is good to get an independent observer to score the condition of your cows. If you are having a veterinarian handle your pregnancy checks, they can be that extra set of eyes to check body condition. Cows in good body condition going into winter need less energy to maintain than poorly conditioned cows. The extra cover and good winter hair growth reduces the amount of energy needed to stay warm.
Knowing what your cows need nutritionally to maintain body condition is critical to calving ease and calf vigor at birth. A 1,200 pound cow in good body condition needs 2 pounds of protein per day and 13 pounds of TDN (total digestible nutrients) up until calving. Knowing what nutrients your feedstuffs are carrying is the biggest money saving information you can have. We recommend that when you get your forages tested you ask for an RFV (relative feed value) and nitrate test. I am going to step on some toes here, but getting just a nitrate test is like shopping for groceries by the warning label, "if it doesn't kill you, I guess you can eat it." A nitrate test gives you zero nutritional information!!
Below are a couple of examples on how to calculate protein and TDN of a forage.
-Alfalfa Hay as fed 19% protein and 60% TDN
-1,200lb cow needs 2lbs of protein/day and 13 pounds of TDN/day
-Protein; 2 divided by .19 = 10.53lbs of this Alfalfa Hay to supply 2lbs of protein/day
-TDN; 13 divided by .6 = 21.67lbs of this Alfalfa Hay to supply 13lbs of TDN/day
-Trying to hit the TDN requirements with Alfalfa Hay would over feed protein. It is a good idea to have another forage source with lower protein to mix with Alfalfa to help balance the cow's needs.
-Sorghum Hay as fed 5.5% protein and 54% TDN
-1,200lb cow needs 2lbs protein/day and 13lbs TDN/day
-Protein; 2 divided by .055 = 36.36lbs of this Sorghum Hay to supply 2lbs of protein/day. (36lbs is more than we would expect the cow to be able to consume. Assuming 25lbs of hay consumption it would supply only 1.37 of protein so you could meet your goal by replacing some of the Sorghum Hay with Alfalfa, or 3 to 4lbs of range supplement.)
-TDN; 13 divided by .54 = 24.07lbs of this Sorghum Hay will supply the 13lbs of TDN requirement for the cow
With Alfalfa Hays ranging from 15% to 18% protein and Sorghum Hay ranging from 4% to 12% protein, you can see that knowing the quality of your forages can make a huge difference in daily cow costs.
Next time we will discuss getting your cow to the finish line, and we aren't talking about calving.
Written by Rick Robbins