Thanks to Chip for sharing this excerpt from his new book “Cow Country Essays and a Little Slantwise Logic!”
Time of calving has to be the first thing considered when moving from a high input operation to a management oriented low input method of raising cattle. So many things are connected to this timing that it creates a significant impact on other segments and compliments all procedures in the yearly cycle.
A calf is born with a summer hair coat. That alone is a warning sign. A calf born in late spring or early summer is in its natural order, just as are all wild animals. A calf born out of time is challenged from day one. Any challenge such as, snow storms, wet weather, sickness (especially when barn calving), and stress of any kind will have a far ranging effect on the calf. A calf born in nice weather has a much better chance of getting off to a good start by not having to fight stress of any kind.
In the early nineteen nineties Dr. Dick Diven published his research findings pertaining to calving in sync with nature. The following is a synopsis of his teachings.
“There are two forms of growth: cell multiplication and cell enlargement. Formation of cells begins with conception and concludes shortly after birth. Cell formation keeps going after birth, but some have suggested that it stops in as few as 13 days.
“Just keep in mind that the little 13-day-old calf on the ground pretty well has all the cells it will ever have. This is a critical period of growth. You do NOT want the calf to experience any kind of starvation at this time. If it does, cell formation will be limited and specialized cells such as nerve and muscle will not fully develop. Make sure the calf has plenty of milk.
“Even though the calf has most of the cells after 13 days, intramuscular fat cells do not happen until around 60% of empty mature body weight. It is at this period that cell differentiation occurs in the muscle. Cells either become connective tissue or fat cells. This is another critical area of growth.
“We want the animal on a rising plane of nutrition at this stage so fat cells will form in the muscle. If the animal is losing weight or just maintaining itself at this time, less fat cells and more connective tissue will form in the muscle. The rising plane does not have to be much, but it does need to be rising. (Author’s note: These fat cells will begin filling around a year of age which coincides with springtime green grass if they were late spring or early summer born, which also cheapens the cost of filling the fat cells.)
“You might think of the muscle as a dry sponge. If connective tissue is formed, the sponge cannot absorb very much. Conversely, if fat cells are formed, the sponge can absorb quite a bit. A fat animal can store 10% of its total fat in the muscle. (Authors note: This is significant for both grass fed animals and replacement heifers. An easy fleshing cow has this along with putting fat on her back.)
Animals that have the ability to store fat can be strategically managed to draw on these reserves when feed energy is short as well as postpartum recovery (Animals should be in good condition by calving time which can be done with green grass if later calving). Animals with mostly connective tissue do not have this flexibility. This ability to store fat cannot be seen or felt.”
The timing of calving should be similar to the wild ruminants in the area. Nature led them to birthing after sufficient growth of new grass to build up flesh from their natural loss through winter. A cow, like the wild animals, should have at least a month to gain weight as this increased weight before calving is recognition of the importance of nature’s natural cycle.
Gary Rhoades comment on summer calving: “I feel I am overworked if I have to set my coffee cup down.”
Reading this very interesting article from Australia and wondering if any planned grazers from this hemisphere have any thoughts in relation to later spring calving?
Before you believe it is all sunshine and rainbows, a couple of questions. Do you rotational graze? Do you cross fence with a strand or two of hot wire? If no, ignore these comments. If yes, consider a newborn calf will cross a hot wire ONCE. He will not return on his own. If he does not get up and nurse he will lay down and die. And you may have trouble finding the buggers in tall grass. If your cross fence is calf proof, you’ll have no issues. Also, cows anticipate moving to new grass, while calves don’t have a clue what you are doing. If you have a six week calving season and move cows once per week, you will have six occasions to move new calves who have no idea what to do or where to go, and the cows will be moved with their heads down grazing, and not much help to you. We start April 15 to have most calved before starting the rotation, and my first two paddocks are big, will last me two weeks each. First move was today, took 2 minutes to move 100 cows, 25 minutes to move the last two calves. Can’t leave any behind! The next one will be easier.
Thank you so much for taking the time to reply. Curious what kind of wire you’re using? I do manage the grazing, moving every one to three days depending on the location for water and the paddock configuration. I’m still using a temporary polywire system. The charge on the line(s) (one or two usually) ranges from 3kV to 7kV. Thankfully, I haven’t had the problem with newborn calves you describe. This is my 3rd calving season, and the calves keep up with their mamas. A couple times the mama of a newborn has stayed in the old paddock with the newborn. When mama is ready, I’ll get them caught up with the herd. The older calves often creep graze under the polywire. I put the bull in on Jun 1 the last two years. I’m going to try Jun 15 this year, but I’d really like to wait until July if the heat isn’t an issue. Thanks again for replying!
Using single-strand Gallagher ringtop posts & polywire and moving daily all through calving, second year, herd is around 50 cows. We have never yet had an issue or lost a calf this way. We often find very young ones bedded across the wire, but they come back in to nurse. The calves tend to cross freely under the cross fence for the first few weeks while they’re small enough; we don’t stress about it. Once in a while a day-old calf gets left behind on a long move across the farm — we just throw it in the calf cart when we’re finished moving the rest. Most of the time even a day-old keeps up with the herd no problem!
In fact, the only ‘day-old though the fence, over the hill and gone’ issue we’ve had was through a 5-strand barbed wire fence, but luckily we found the bugger alive after a half day searching with the dogs.
I use two strand high tensile wire, top wire hot only, on wood and steel posts. 5-7kv is the goal. Some of my moves are 1/4 mile, so allowing them to find each other is not an option for me. I have had calves hunker down 75 feet from the dam and not attempt a second crossing. Putting a switch on the bottom wire and leaving it off until later in the season helps, but vigilance is still necessary for the new ones.
Thanks for this article. I’m a beginning farmer on the steep end of the learning curve. Where I live in northeast Oklahoma, to calve after the cows have been on spring grass about 30 days, I’d want my herd to calve in early to mid May. That gives me a breeding window between Jul 23 to Aug 30 if I follow the recommended 42 day breeding window. I’ve been cautioned by local herd managers that breeding during that hottest part of the year could result in decreased fertility & have found articles that back that up. Curious if anyone has insight on what folks in this situation are doing? The other farmers I know are calving in March. I’m working on improving my winter grasses, but my herd sure looks better right now (May 20 than they did in March.) I looked up the Whitetail Deer gestation rate. It ranged from 198 to 205 days in various sources. This shorter gestation rate allows the deer to breed in the fall (mid Oct thru Nov) when temps have cooled & still calve in May & June. So–what’s the decision driver for cattle–breeding date for heat issues or calving date for nutrition issues? Many thanks for any thoughts folks have time to share.
I heard Dick Divens presentation many years ago, and moved from mar/april to May/June calving.
My first calves just started arriving this week. The cow herd has had about 4 weeks of great quality spring grass to eat and put some body condition back on after winter. Peak lactation when intake demands also peaks will occur during our forage peak in June, our cheapest forage of the year. Ground temps are warm, paddocks are clean.
What could be simpler, calving shouldn’t be stressful.
Kris Ringwall, NDSU Beef Specialist at Dickinson has a great series of posts on their move to late spring calving and the economic success it has meant.