The 2024 autumn season is in full bloom with vivid tree colors. It’s a favorite time of year for those who love the outdoors. Unfortunately, cows are color blind and unable to enjoy the vivid red colors of the season, but they love the cooler temperatures.
The fall season can often bring challenges to a dairy farmer because of the changes that occur this time of year. Let’s review some of the factors that affect the dairy herd performance in the fall and how to manage the impact of these factors.
Feed changes
2024 corn silage yields across Ohio and Pennsylvania from farm reports indicated lower yields. Laboratory 2024 corn silage test values show higher starch content in the corn silage, which indicates less stalk and more grain in the corn silage. Laboratory test data shows high fiber (NDFd) digestibility which is typical of drier growing conditions.
One challenge with new crop corn silage is lower kernel digestibility. Aged, well-fermented corn silage will have higher corn kernel digestibility, as the fermented silage acids break down the corn zein protein structure to increase rumen starch digestion.
Laboratory measurements of 7-hour starch digestion in corn silage give your nutritionist essential information to accurately adjust and balance rumen-fermentable starch in your dairy ration.
Dairy farmers who are successful in feeding new corn silage without production losses can use management practices and decision tools to improve performance. These practices include selecting proper hybrids (floury starch), applying in-season corn leaf protection (fungicide), ensuring proper kernel chop processing at harvest (score >77), working with their nutritionist to formulate TMR diets for proper rumen starch and NDF digestion, adequate but not excessive uNDF, adequate rumen peptide and ammonia levels and proper vitamins and minerals, including DCAD balance.
Feed enzyme additives can at times benefit new crop silage but responses are variable. Seek out research-proven results when selecting additives. Each farm and region will have variations in corn silage analysis. Keep communication open with a qualified dairy nutritionist about your corn silage results and make proper adjustments to avoid any fall slump in cow performance.
Day length
Lactating dairy cows perform best when provided 18 hours of day length and 6 hours of darkness. As day length shortens in our region in the fall, dairy cows’ hormones shift to produce less milk. Long-day lighting especially for northern U.S. regions has been studied extensively at many universities. A consistent 4-to-6-pound milk response has been shown in the studies. It requires several weeks for the response to show.
Added light must be installed in dairy barns to maintain the recommended day length of 18 hours to achieve proper day length. Day length does not mean leaving a few 60-watt bulbs on in the barn. To properly impact the cow’s hormonal response, a minimum of 20-foot candles of light must be present in the cow’s eye.
A qualified electrician can measure light intensity with a light meter in the barn. Light meters can also be purchased.
A rule of thumb is that 20-foot candles of light are required to read the fine print in the Farm and Dairy newspaper when its held with extended arms at an arm’s length. Humorously, perhaps some of you cannot read even the large print at an arm’s length! That is not due to light intensity; that is probably due to the need for reading glasses.
The bottom line is, give your cows 18 hours of light that measures 20-foot candles at their eye level.
Summer heat
Summer heat and humidity in the Midwest U.S. will have a lingering effect on dairy cows. Cows that calved in the late spring and achieved peak milk in the summer can have lower body conditions and less persistent milk production in later lactation. A shorter day length in the fall signals the cow to replenish body condition instead of production, so the energy the cow consumes is diverted away from milk toward body weight gain. This can reduce late lactation production and lead to overall lower herd performance.
Summer heat can often reduce fertility in cows where embryo quality is compromised from hot summer temperatures and cows do not conceive consistently resulting in lower conception rates, longer days open, longer days in milk and lower production. Thus proper summer heat abatement is a key tool that is useful in reducing fall production declines.
Cows that stand on their feet for excessive time due to heat stress will have poor-quality hoof tissue and more potential lameness. Maintain proper cow comfort all year around, but especially during the summer heat to avoid fall hoof issues.
Birds
As birds mount their annual flocking, they are drawn to indoor feeding and nesting areas in dairy barns. Birds can transmit disease and dysentery, consume grain from TMR and reduce performance. The recent diagnosis of avian influenza in dairy herds is a concern. Influenza can cause significant economic milk production losses.
Be vigilant and implement a sound biosecurity plan to reduce cattle movement, bird infestation and disease transmission from other farms.
Facilities
In some herds, the fall can result in more confined and unclean calving pens and poor air quality. This can result in more metritis, mastitis and respiratory health challenges. These health challenges can elicit an immune response that can reduce milk production. Dairy cows with compromised immune systems can drop milk production by 8 to 20 pounds of milk per cow per day.
Provide clean, well-ventilated facilities and consult your veterinarian to maintain updated vaccination protocols. Feed additive products are available, some experimental, to reduce health challenges in your herd. Discuss options with your nutritionist.
Evaluate and select the best. The fall season of 2024 has brought vibrant tree colors to Ohio and Pennsylvania. As dairy farmers, take a moment to enjoy the beauty and one of the best seasons of God’s creation.
To help your cows do their best, manage fall feed changes, consider long-day lighting, provide great cow comfort, implement a biosecurity plan, reduce bird infestations and provide quality clean housing.
