Top 10 factors limiting nursery calf group feeding systems
Automated calf feeding systems continue to increase in popularity throughout the upper Midwest despite little uniformity in facility design, feeding method, and performance across farms and no industry-wide accepted model to balance facility performance and cost.
My opinion is that the technology in automated calf feeders is quite good, however, many farms still struggle to manage calves in groups. We have identified 10 common factors limiting group feeding systems, and suggest some strategies to correct these shortcomings and monitor success.
1. Open herds without proper cattle biosecurity. We recommend a closed herd for one year prior to group-feeding nursery calves. Allow time for vaccination protocols to take effect and for the cow’s immune system to recognize and respond to novel bacteria and viruses, resulting in a more immunologically competent colostrum and therefore better calf health and performance. Make sure purchased cattle have adequate vaccinations and are ideally isolated from the herd for a month prior to introduction.
2. A subpar vaccination program. Farms that do not have an adequate vaccination program for dry cows and heifers should consider postponing group nursery calf feeding until a protocol can be put into place. Work with your veterinarian to ensure cattle receive the right vaccine at the right time.
3. Inconsistent or inadequate colostrum program. Rock solid maternity and colostrum programs are the foundation for successful group-housed nursery calves. Calves gain immunity from the dam via colostrum that provides protection during the first 10 days of life as well as aiding in maturing gut functionality. One calf in a pen with failure of passive transfer will not only be a poor performer herself, but will decrease calf growth of the whole pen. Monitor serum total protein with a goal of 6.0 mg/dL or more in 90 percent of the calves.
4. Feeding excessive milk amounts. For better or worse, most autofeeder managers feel they need to maximize milk intake. We often see feeding rates in excess of 8 L at a solids concentration of 150 g/L. At this feeding rate, calves will consume 2.6 pounds of powder or 42 ounces of powder per day. Healthy calves in a clean and comfortable environment can handle this amount of milk, but disruption of intake or digestive health at this high of feeding rate can set up calves for health challenges. Review milk and starter intake with your nutritionist to determine if other areas of opportunity exist to manipulate the feeding curve to increase calf health and efficiency.
5. Feeding high-osmolality milk. Osmolality is the sugariness and saltiness of milk, and it plays a large role in water balance and passage rate in the intestines. Milk replacer osmolality is influenced by the lactose and ash content. Lower lactose (higher protein and fat) and ash will contribute to lower osmolality and a reduced risk for gut upset. Additionally, osmolality increases as the bacteria count increases in whole milk. So, even if milk is pasteurized, high bacteria milk has a greater osmolality than low bacteria milk. Milk additives can also increase milk osmolality, so consult your nutritionist to make sure the correct additives are being used in the correct amounts.
6. Inadequate water fountain hygiene. Saliva and nasal secretions are primary vectors for pathogens. Drinking fountains provide a wet surface for oral and nasal secretions to bloom. Additionally, most drinking fountains are not installed with cleaning and sanitation in mind, allowing pathogen loads to build, especially during respiratory outbreaks. Develop a protocol to clean and sanitize drinking fountains daily. Evaluate water hygiene with ATP surface and water swabs. Offer electrolytes in a milk bar for free-choice consumption.
7. Large variation in calf age in the autofeeder pen and barn. We need to learn from our colleagues in the swine industry that minimizing age variation in a pen and barn are hallmarks of disease control. Ideally, age variation in pens should be less than one week. Fill autofeeder pens quickly and calves should remain in the pen until they are weaned and ready to move. Continuous flow systems, where calves make multiple moves and are regrouped with other calves, have not proven to be a successful strategy. Additionally, older heifers and nursery calves should not be housed in the same facility.
8. Failure to detect, diagnose and treat infections. Strive to be proactive instead of reactive. Calves with obvious clinical infections have likely already infected the rest of the pen. Train employees to see changes in calf behavior before clinical health issues occur. Isolate chronic calves until they have recovered.
9. Inconsistent air quality and excessive pen moisture. We target a minimum of four air changes per hour in the winter and a minimum of 20 air changes per hour in the summer. Curtain sides and power ventilation are necessary for calf barns in the summer. Maintain dry bedding and keep air ammonia less than 10 ppm.
10. Excessive pen stocking density. To minimize group calf health issues, maintain about 16 calves per nipple. Risk for disease exposure appears to increase exponentially with an increased number of calves in the pen. Unknown social factors are also likely at play that impact feeding and resting time.
This article was originally written for the June 2017 edition of Vita Plus Starting Strong calf care e-news. Click here for more calf care and nutrition expertise.
About the author: Dr. Noah Litherland is the Vita Plus dairy youngstock technical specialist. he grew up on a diversified livestock farm in central Illinois and was active in 4-H and FFA as a youth. He earned his bachelor’s, master’s and Ph.D. from the University of Illinois, focusing on dairy cattle nutritional physiology. He worked as a dairy extension specialist at Oklahoma State University from 2006 to 2008 and then as a dairy nutritionist at the University of Minnesota until 2014. At Minnesota, Litherland served as the faculty supervisor of dairy research on the St. Paul campus. Read Litherland’s most recent article.
Calf and heifer nutrition