WESTERN PRODUCER — Our disease investigation unit at the Western College of Veterinary Medicine in Saskatoon is typically busy this time of year with outbreaks of neonatal calf diseases and some abortion storms as well.
I’ve worked with several local veterinarians who described calves that were dying in the first few days of life.
The typical clinical scenario was young calves that were dying at less than a week of age. These weren’t huge outbreaks, but the producer had lost a cluster of four or five calves in the last week or so and was concerned.
In most cases, the calf seemed normal at birth, but suddenly became very weak and lethargic and stopped suckling.
With a rapid progression, the calf would become unable to stand or drink and sometimes showed signs of rapid breathing before dying.
In a few cases, the calf might demonstrate diarrhea or some neurological signs such as head pressing or “star-gazing” before becoming almost coma-like.
When these calves were sent to the diagnostic laboratory for a post-mortem examination, the veterinary pathologist reported significant congestion and inflammation in many organs including the heart, kidneys, intestines, lungs, spleen and on the surface of the brain.
We were able to culture some bacteria such as E. coli out of these tissues, which suggested the diagnosis of septicemia.
Septicemia is a systemic disease, meaning that multiple organs and body systems can be affected at once. Septicemia is confirmed by demonstrating the presence of bacteria and/or their toxins in the blood of the calf and the resulting systemic inflammatory response in multiple organs.
The bacteria that are responsible for septicemia are often those that can be normally isolated from bovine feces such as E coli.
It can be a difficult disease to treat because it progresses so rapidly and by the time the calf is identified as sick, there is significant organ damage already occurring that is difficult to reverse.
Veterinarians will usually try to treat these cases with antimicrobial therapy and supportive therapy, such as intravenous fluids and electrolyte support.
Why do calves get septicemia? There are really two very important factors. The first predisposing risk factor is inadequate passive transfer of immunity, which is a result of inadequate intake of colostrum. In virtually all these cases, we can demonstrate with a simple blood test that these calves probably didn’t get adequate colostrum.
The second major risk factor is the contamination of the environment the calf is exposed to in the early days of life. In many herds, we tend to see this disease occur later in the calving season, when the calving barn or calving pens have become more contaminated with feces over the calving season despite the producer’s attempt to provide lots of bedding.
Almost all calves that suffer from septicemia have had inadequate colostrum intake, and as a result have lower levels of immunity to many of these common bacteria.
The intestine of the calf is only able to absorb these large antibodies in the mother’s colostrum in the first few hours of life.
As a result, there are three factors that influence the calf’s absorption of passive immunity. The timing of receiving colostrum is important and should occur ideally as early as possible, preferably within the first six hours of life.
The second factor is the amount or volume of colostrum that the calf consumes. I think this problem occurs more often than we think. Many producers report they saw the calves suckle and therefore didn’t think they had to intervene.
Finally, the third factor is the quality of the colostrum, or the concentration of the antibodies in the colostrum. This seems to be more of an issue in dairy herds, although it hasn’t been studied extensively in beef cattle, other than a few recent studies.
We can test cow colostrum to assess quality with a device known as a Brix refractometer, which is often used for beer or wine making. Poor quality colostrum could be an issue in herds that have significant nutrient deficiencies caused by an inadequate diet over winter.
The bacteria that cause septicemia are common environmental bacteria that can enter the calf through the mouth and nose or through the umbilicus.
The newborn calf intestine hasn’t been colonized with all the normal adult intestinal flora yet and so it can be more susceptible to bacteria that might cause disease because of a lack of competition.
Two other diseases that are often seen at the same time as septicemia are joint infections and umbilical infections.
These are usually septicemia cases that didn’t result in widespread organ damage and death, but the infection settled in one area such as the umbilicus or the joints.
The calves that display neurological signs are often situations where the lining of the brain is infected and the calf has meningitis because of the septicemia.
Therefore, the second factor that we can control to some degree is the amount of contamination of environmental bacteria the newborn calf is exposed to.
Having a separate wintering area for cows and heifers and moving the herd into the calving area just before calving will help minimize fecal contamination.
Reducing the density of the herd and minimizing the use of a calving barn as much as possible are other important factors, but this is often easy to talk about and hard to implement if you are calving early in the calendar year. Creating a separate turn-out area and moving cow-calf pairs into the turn-out areas as soon as they are mothered up will also help to minimize the risk.
The Sandhills calving system is another alternative that moves pregnant cows into clean calving areas, leaving behind the cows with calves.
Septicemia is difficult to treat and so we need to rely on prevention as much as possible.
The two important risk factors are colostrum intake and environmental contamination.
Often it is easier to manage colostrum intake during the calving season. Make sure to pay close attention to calves that may have difficulty in obtaining adequate colostrum. This probably means providing supplementation for the calf by tubing it with colostrum from milking out the cow or using a good quality colostrum replacer.
Pay special attention to high-risk calves, which would include calves from heifers, calves that you had to pull, calves born on cold days, and calves born to cows with poor udder conformation.
Checking the suckle reflex in newborn calves can help you decide if you need to interfere. Your veterinarian can help with some simple, inexpensive diagnostic testing to assess colostral transfer in calves less than a week old, to assess how well you are doing in managing colostral intake in your herd.
John Campbell is a professor in the department of Large Animal Clinical Sciences at the University of Saskatchewan’s Western College of Veterinary Medicine.
