By Naomi Paley, BSA, PAg, Regional Livestock Specialist, Yorkton
Although feed quality from the 2017 forage crop was above average, yields were lower due to the dry conditions we experienced. The winter’s cold temperatures and wind chills have taken a pretty big bite out of the feed stack and many producers are finding themselves wondering how to stretch what feed they have left until green grass is available.
Pregnant beef cows that have kept the fetus for 3 months are physiologically committed to carry it to term. As fetal growth starts to accelerate in mid and late gestation, the demand for energy, protein, minerals and vitamins ramps up. The cow needs to consume these nutrients in adequate amounts to grow a healthy calf and maintain her own health. As she enters the third trimester, she runs into the situation where her capacity to eat is limited by the calf taking up space inside of her while her requirements for nutrition are increasing. We can combat this by providing better quality forage or some additional energy supplement.
If nutrient intake is significantly below requirements, she will deplete her own body resources, including fat, her muscle protein and her stores of minerals and vitamins. As a result, she may lack sufficient muscle tone and endurance to deliver the calf quickly and efficiently. Long deliveries put stress on both the cow and her calf. In severe cases of undernutrition of protein and energy, calves are born weak and unmotivated to get up and suck. They may be suffering from acute Vitamin E/selenium deficiency (White Muscle Disease), leading to extreme muscle weakness.
Overall, calves from malnourished cows lack the muscular strength and coordination to get mobile, and lack the mental alertness and drive to bond with the cow and fulfill their instinctive urge to find the udder and suckle vigorously. Without help, many of these calves will die. Those that survive will be at risk from infectious disease, as they may not obtain adequate colostrum volume, and these cows will likely produce low quality colostrum which is deficient in immunoglobulins.
Calves born into this whirlpool of negativity may succumb early, or they may struggle through calf hood after suffering setbacks from diarrhea and other diseases. They will likely be smaller at weaning due to lowered maternal milk production and the impact of disease. Cows in this situation will be slow to cycle and breed back, and are at risk of coming up open in the fall.
Making up for lost nutrition:
While all of this may seem a little overwhelming to accept as being the result of short feed supplies and subpar nutrition, there are actions we can take to make things better.
If an alarming number of weak calves are born in a calving season:
- Get your vet out.
- The cause may be due to an infectious disease such as bovine viral diarrhea (BVD). Swift action is needed to find out if pathogens are the culprit and mount an effective campaign against them.
- Get dead calves necropsied.
- Inject newborns with Vitamin E/selenium, and Vitamins A and D – if injectable vitamins are not available, you can give calves vitamin A and E capsules sold over the counter at your local pharmacy. The gel capsules can be administered using a bolus applicator.
- Discuss the idea of injecting the cows with Vitamin E/selenium with your vet.
- Provide supplemental colostrum (fresh or frozen) or artificial colostrum products to calves which did not strongly suckle within the first 12 hours, or whose dams who do not appear to be milking well.
- During cold or rainy weather, get weak calves dried off and warmed up, then started on the cow or fed supplemental colostrum.
- Put the cows on your best forage. If you don't have good quality forage, then feed each cow a few pounds of an energy/protein concentrate (pellets or grain) per day.
- Provide cows with a salt/mineral mix which contains the right levels of calcium and phosphorous and adequate levels of trace minerals and vitamins.
Management after the calving season:
- Ensure cows are gaining weight going into breeding.
- Keep them on good quality pasture or supplement with an energy/protein concentrate.
- Provide a salt/mineral mix that has the right Ca and P levels to match the feed, and contains adequate levels of selenium and other trace minerals such as zinc, iodine, copper, manganese and cobalt.
Management for fall & winter:
- Get lab analyses done on your stored forages.
- Feed a salt/mineral mix to match the calcium and phosphorous in your feed, and which contains adequate levels of all of the trace minerals and vitamins.
- Body condition score cows and group them for feeding - thinnest cows get the best forage.
- Supplement with energy and protein as needed.
- Monitor cows over the winter and make adjustments to the feeding program if necessary