The quest for a magic formula that transforms a commodity with very little value into a commodity with a much greater value has been underway since currency trade replaced the barter of goods and services. The Brother’s Grimm published a fable in the early 1800’s of a little man that spun straw into gold. One of the goals of many alchemists’ was to turn iron ore into gold. While the cow is not traditionally considered a mythical creature, she is capable of converting low value commodities such as straw, into a commodity of greater value, beef.
Granted, the cow is not capable of converting straw by itself, nor does she convert it in a directly proportional manner, but she can survive and reproduce quite nicely on a combination of straw, some grain and a limited amount of alfalfa hay. Beef producers in west central Saskatchewan have known about this formula for generations and have built systems to winter their beef herds in this manner. When the green grass reappears, the cows very quickly decide that what they have enjoyed all winter is no longer appetizing. Much like you and I would turn up our nose at a bowl of oatmeal for supper while a roast beef dinner with all the trimmings sat on the kitchen counter.
Not only does the cow desire to eat the fresh, green grass, the producer wants to reduce the daily burden of chores. It is so much easier to watch cows gather their own feed and insure that the water system is working than to manipulate bales, pull twine and carry chop pails. Once the fence is checked, it is pretty tempting to just open the gate and let them be happy in the green grass.
If the pasture was managed so that there is a significant carryover of vegetation from the previous growing season, things will progress rather well. Usually the pasture has been eaten right down the previous fall and the only
available forage is fresh growth. The new growth is highly digestible, high in protein and over 80% moisture. This is a significant contrast to the previous day’s diet of dry hay, straw and some grain, with a relatively slow rate of digestion, and adequate protein. The fresh pasture represents the same level of shock to the rumen microbes that access to a bin full of grain would. While fresh pasture is rarely implicated in severe animal distress in the immediate timeframe, the digestive disruption caused by the dietary change, may be a contributing factor to issues later in the season.
One of the most likely issues will be an outbreak of sandcracks and foot rot 6 to 8 weeks after turn out. The explanation for this is that the digestive upset, interferes with blood flow to the extremities, resulting in poor nutrition provided to the feet, resulting in what is commonly called a hardship groove. This represents a weak point in the hoof wall which grows out from the coronary band at a rate of roughly ¼” per month. When the groove gets to be about ½” down from the coronary band, the stress of the animal’s weight on the foot exploits the weakness in the hoof wall, causing a crack to form. This crack may be painful, but it also allows bacteria a way to penetrate the foot and cause infection.
The timing of this outbreak may coincide with a significant portion of the breeding season, and animals that are uncomfortable standing with their own weight are not likely to be interested in supporting another’s weight as well. Antibiotics commonly used to treat foot rot interfere with sperm production, so if the bull requires treatment, then you might as well pull him from the pasture too.
Given that most feed piles will be looking pretty small by the time green grass appears, waiting for the grass to get more mature prior to turn out isn’t likely to happen. Limited pasture growth last year as a result of limited rainfall, means that carryover levels are likely very low on many pastures. The strategy of providing good grass alfalfa hay for this first three weeks on pasture to minimize digestive upset and smooth out the transition to pasture is the most workable solution