Ask the Vet
Pros and Cons: Grazing Crop Residue
READER: What things should I be aware of if I'm turning cows out on crop residue?
DR. McMILLAN: I will focus on animal health and leave the debate about the value of residue to soil fertility to the crop scientists. I will also say this is not a common practice in our area, so I would welcome input from those who have done this with their cattle.
Grazing crop residue can be a low-cost supplemental feed for cows, especially dry cows in the mid-trimester to early third trimester when nutrient requirements are lower. But, there are several potential problems.
On harvested corn ground, there is a potential to eat too much grain, which can lead to rumen acidosis, bloat and founder. Corn residues from highly fertilized crops can be very high in nitrogen. In our area, corn will often sprout and grow after harvest. These plants can be very high in both nitrates and prussic acid, or hydrogen cyanide. If these young plants are stressed by drought or frost, toxicity can be dangerously increased. Toxic plants, especially around the field margins, is another issue. In our area, we are particularly concerned about coffeeweed and sicklepod, but your area may have different plants.
As winter progresses, and crop-residue quality decreases because of grazing selection and weathering, supplementation of protein and phosphorus will likely become necessary. So, yes, if done properly, crop residues can be a great option for many producers.
READER: What is the best way to wean calves?
DR. McMILLAN: I like to wean fenceline to fenceline or nose to nose. This is much less stressful on mamas and babies, but you must have a good fence. I use an electric fence. This method has worked well for me and other producers I have recommended it to. The animals bellow and squeal for a few days, and then all is good.
If you move cows or calves to a pasture across your farm or to a new location, make sure your fences are very good. The last year we did this, a cow jumped and/or tore through three fences. We spent hours doing repairs. Her number was 343. You remember a lot that is learned in the school of hard knocks.
Another method is weaning rings that prevent the calves from nursing. These rings are applied in the nose of calves, and they are turned back with their dams. This does add two trips through the chute, but this would be an opportunity to vaccinate calves before the stress of other methods of weaning. I have had no experience with this method. We would appreciate comments from readers who have used it.
The worst method in my opinion is to wean and ship the calves to the sale barn. This is the highest stress event in a calf's life, and to add in the extra stress and disease exposure in a sale barn is a really bad idea. This will cost you money. Order buyers will discount these green calves. And, it is not good for your industry. As I have said before, we are all in this together.
**
-- Please contact your veterinarian with questions pertaining to the health of your herd. Every operation is unique, and the information in this column does not pertain to all situations. This is not intended as medical advice but is purely for informational purposes.
-- These are only my thoughts and general guidelines. Please get with your veterinarian and together develop the best program for your herd.
-- Email Dr. Ken McMillan at vet@dtn.com
[PF_1124]
(c) Copyright 2024 DTN, LLC. All rights reserved.