Spring is just around the corner and calves are already hitting the ground for many producers. One of the most common concerns amongst cattlemen this time of year is calf scours and general neonatal calf health.
Calf death and disease in the first couple of months post-calving is a significant source of lost production for many operations. The latest information on the subject suggests that neonatal calf health is by and large an issue of management. I'll discuss three topics of primary importance.
1. Prevent Dystocia
Preventing dystocia is a good first step in ensuring a successful calving season and in protecting neonatal calf health. Not only does dystocia often result directly in calf mortality, but calves that survive a difficult delivery are 2.5-6 times more likely to become sick early on in life. The two major causes of dystocia in cows and heifers are disproportionately large calves and/or small pelvic area of the dam. Start by choosing bulls with low birth weight EPDs and superior calving ease EPDs that still maintain good weaning weights and yearling weights. For pelvic area, consider pelvic area measurement on yearling heifers, establishing a minimum threshold used for culling out problem calvers. Lastly, be sure your heifers are reaching 65 percent of their mature body weight at breeding and 85 percent mature body weight and a BCS of 6 by calving.
2. Colostral Intake/IgG Absorption
Healthy calves are those that have a normal delivery and quickly stand and nurse their dam. A calf’s immune system is immature and naive at birth and likewise a calf must obtain passive immunity from the absorption of adequate antibodies found in colostrum. Basically, calves must nurse early. Most of the absorption will take place in the first 6-12 hours after birth and little if any will occur after 24 hours. Failure of passive transfer (FPT) is common in beef herds estimated at anywhere from 10-40 percent. FPT calves are significantly more likely to become sick in the first 30 days and more likely to die prior to weaning. Therefore, select for cows with good mothering ability and sound udders with small teats that are easy for calves to nurse. Keep those cows well-vaccinated (scours vaccines and others) and in good body condition and provide plenty of protein in the diet during the last months of gestation to allow for superior colostral production. Remember again, to prevent dystocia and also plan for decent weather at calving time.
3. Calving Site and Season
Baby calves act as biological amplifiers. They pick up a small number of pathogens from the environment, act as an incubator and then shed larger numbers back into the environment. The next calf is, in turn, exposed to a greater pathogen load. This phenomenon continues until a few calves down the line you have an outbreak of scours. How do we prevent this? First, shorten your calving season to 60-90 days and consider moving pairs from the calving pasture to designated nursery pastures creating groups of calves that are similar in age and therefore eliminating the amplification of pathogens between calves. Calve heifers early and provide a clean environment and plenty of space for your calving herd. Delegate a calving pasture and leave it vacant until 1-2 weeks prior to the calving season. Prevent congregation of cattle and concentration of pathogens by moving feeding sites (bunks, round bale feeders, unrolling bales) often and keeping them distant from water sources and mineral bunks. In effect, spread out the cows and spread out the pathogen load.
These three strategies may all require significant effort for implementation into your management protocol, but if you are looking for solutions to your calf health issues these solutions are worth your time this spring and for subsequent calving seasons.
Darren Loula, DVM, is a large animal veterinarian at Fair Grove Vet Service in Fair Grove, Mo.
