Thanks to the Beef Cattle Research Council of Canada for this piece!
Last week we looked at the system Doug Wray uses to prevent disease spread in his newborn calves. His process is a variation of a system developed at the University of Nebraska about 20 years ago, known as the Sandhills Calving System (developed on pastures in the Sandhills of Nebraska).
The Sandhills System was designed to protect calf health by providing separation between newborn calves and older calves (two weeks of age and older) during a critical time of the year when the risk of disease development, primarily scours, is high. Newborn calves co-mingled with older calves, particularly if they are concentrated in a relatively small area, and particularly if weather conditions are cool and wet is really the ideal scenario for the development of a scours outbreak in a cowherd.
How Do Scours Spread?
Research has shown the cycle of scours at calving often originates with mature beef cows as they carry the scours pathogen. Scour pathogens are viruses, bacteria and microscopic parasites. Cows shed the pathogen on the ground in manure. Newborn calves often pick up the pathogen and may not become sick, but their guts serve as pathogen-multipliers. These calves shed an increasing load of pathogen onto the calving ground, then newborn calves come along and pick up the heavy load of the bacteria. The dose-load of pathogens overwhelms the calf’s ability to resist disease, and suddenly the beef producer is dealing with a bunch of sick calves. And if a beef herd calves on the same area year after year, the soil can also be contaminated with scour-causing pathogens. So by keeping the more vulnerable newborn calves on clean ground away from the higher-risk two-week and older calves, the risk of a scours outbreak is greatly reduced.
As most producers know, scours or other early calfhood diseases such as pneumonia not only reduce calf performance, but often result in death and those add up to an economic loss to the producer. Results of the 2014 Western Canada Cow-Calf Survey (WCCCS), for example, reported that scours and pneumonia accounted for about 30% of calf deaths. The 2017 WCCCS survey reported similar losses with about 25% of calf deaths attributed to scours. Taking it a bit further, other Canadian beef industry research showed while calves treated for scours can survive, their performance is compromised, resulting in weaning weights anywhere from 15 to 30 pounds lighter than counterparts that didn’t get sick. And still other industry research calculated the overall cost of calf death loss, treatment costs, and reduced performance in a 100 head beef herd with a 20% incidence of scours resulted in a $40 per head cost per bred cow or about $4,000 in that year.
Setting Up a Sandhills Calving System
Many Canadian veterinarians and other animal health specialists are encouraging more producers to consider the Sandhills Calving System or some variation to reduce the risk of calf losses due to disease. Dr. Elizabeth Homerosky, a veterinarian with Veterinary Agri-Health Services in Airdrie north of Calgary, regularly recommends the Sandhills Calving System or modifications thereof to her clients.
“The traditional Sandhills system has been proven to be effective in reducing the risk of scours in calves,” says Homerosky. “But an important consideration is that it takes some planning. Among the first considerations — producers need to have enough land available to handle each group of cows and calves over the calving season,” she says. “The herd should be split about every two weeks with the cows that haven’t calved moved to a fresh pasture. If a producer has a 60-day breeding season, for example, they would need to have planned for five pastures with adequate holding capacity.”
Homerosky often works with producers to develop a pasture chart to handle cattle numbers. If the producer has 300 head of bred cows, for example, the starting #1 pasture needs to be large enough to accommodate the whole herd and first batch of calves for two weeks. Pasture #2 needs to be large enough to hold the estimated number of cows still to calve for another two weeks and so on.
Homerosky says proper fencing to provide separation of the calved and yet-to-calve herds is important. She says a single strand electric wire to divide pastures usually isn’t sufficient as calves can cross under the wire and mix.
Another important planning aspect includes providing adequate water for each herd in their respective pastures. Depending on calving season dates, water may need to be available quite early in the spring.
Homerosky says newborn calves are most vulnerable to some of the scour-causing pathogens within the first weeks of life, but their immunity grows as each day passes, provided they received adequate and good quality colostrum at birth. Once calves reach about four weeks of age their immune system has developed sufficiently to fight most scour-causing pathogens.
While the original Sandhills Calving System involves a pasture sequence that leaves cow-calf pairs behind as the yet-to-calve cattle are moved to fresh ground, there are variations that work, as well. Doug Wray described a pasture calving system that works for his operation. Homerosky says she has also worked to develop a modified Sandhills calving system with producers who prefer to the keep the calving herd close in to corrals and calving facilities and move the cow-calf pairs to new ground. These may be smaller beef operations, purebred producers, or farms with a smaller land base.
“I often refer to it as the Foothills Calving System,” says Homerosky. This variation is just the reverse described in the Sandhills system. The bred cowherd is held in one pasture or calving area, and as soon as calves begin to appear, cow-calf pairs are moved to the next area or nursery pasture.
Under the Foothills system, Homerosky recommends cow-calf pairs be moved away from the main pregnant cowherd within 24-hours of calves being born. For example, if 10 calves are born today, as soon as they have nursed and are ambulatory move that group to the new paddock or first nursery pasture within 24 hours. If 10 calves are born tomorrow, do the same thing — move those pairs into the paddock or nursery pasture to join up with the first day’s calves. Ideally she recommends following this approach for about 10 days (no more than two weeks). Keep moving cow-and-newborn-calf pairs into that first nursery pasture for 10 days to two weeks (or before if the pasture reaches capacity). At the 10 day to two-week mark start moving cows and newborn calf pairs to fresh ground in a new second nursery pasture and continue using it for 10 to 14 days before starting a third nursery pasture.
“Newborn calves do not shed any scours pathogens in their manure within the first 24 hours of life, so that’s why it is important to move those calves within 24 hours,” says Homerosky. By moving the pairs it limits their exposure to any pathogens that may be present around the main cowherd and they are also not adding to the pathogen load in the calving area.
If by some chance a case of scours does develop, the Foothills systems allows a producer to contain or manage the outbreak to within a small group of animals, rather than whole herd.
Claire Windeyer, a veterinarian and associate professor at the University of Calgary has seen these systems work extremely well. “It is really all about providing the newborn calf with a good environment,” says Windeyer. “It does take proper planning and management and time on the part of the producer but getting those calves to a clean environment is the best means of reducing the risk of calves developing scours. No system provides a 100% guarantee but it certainly increases the odds of raising a healthy calf.”