by A.J. Tarpoff, DVM, MS, Beef Extension Veterinarian
Neonatal calf scours (diarrhea) is a multifactorial issue. The risk and occurrence can change year to year based on many different factors. Typically, early spring calving due to the cold, wet and windy weather, creates some unique challenges in combating calf scours for cattle producers.
Causes
Scours can be initiated by infectious agents such as viruses, bacteria, and even protozoan parasites. It is important to note that most of the pathogens of concern are shed at low levels through the feces by healthy members of the resident cowherd. Most of the disease and death loss related to scours occurs within the first month of age. The bacteria, E. coli, is a common culprit within the first 5 days of life. Rota virus, Corona virus, and cryptosporidium (protozoa) are commonly identified in cases between 1 week and 3 weeks of age. Mixed infectious with more than 1 pathogen commonly occurs as well. Salmonella and Clostridial infections can also occur with minimal clinical signs before acute death.
Nutritional causes of neonatal diarrhea can also occur. “Milk Scours”, as it is often referred to, is a non-infectious cause of white loose manure. This tends to occur after a cow/calf separation event. The hungry calves tend to over eat leading to undigested milk passing through the digestive tract. The intestinal disruption is often self-limiting and clears up within a day or two without treatment.
Clinical Signs
The most common clinical signs of calf scours are watery stool, lethargy, and dehydration.
- Diarrhea: The color of the stool can be brown, green, yellow, or grey in color. Tail and the rear legs may be covered in wet manure. Bloody stools can also be seen with Salmonella, Clostridial, or coccidiosis.
- Lethargy: noted by decreased desire to nurse, depressed attitude, and reluctance to stand. Staggered walk may also occur.
- Dehydration: identified by having sunken eyes. Another effective means to measure dehydration is by tenting the skin of the calf. A well hydrated calf’s skin will snap back flat after pinching it. if it takes 1-3 seconds, the calf would be ~6-8% dehydrated. If the skin tent takes up to 5 seconds, the calf would be ~8-10% dehydrated. The severe loss of fluids also interrupts the calf’s acid/base and electrolyte balances
Treatment
The most important thing to do when deciding how to treat calf scours is to work with a local veterinarian. They have the expertise to help guide producers through the process on how to intervene to give the best chance for calf survival. Treatment of calf scours is directed toward correcting the main issues: Dehydration, Acid/Base imbalance, and Electrolyte imbalance. Fluid therapy is typically the first step in scour treatment. This is usually carried out through oral electrolytes and fluids to correct the dehydration and continued loss. There are many electrolyte formulations available on the market. Not all formulations are the same. They are formulated for many different purposes depending on electrolyte, energy, and pH buffering needs. Selection decisions of these products should be made with the input of a veterinarian. Always follow label directions when mixing and administering electrolyte solutions. However, if the calf is severely dehydrated IV fluids administered by a veterinarian offers the best chance to recovery. Many times the calves lose their ability to maintain proper body temperature. Supportive care through thermal support during the course of disease may help increase calf vigor, desire to suckle, and mentation. Veterinarians may also include oral or systemic antibiotics in certain cases when it has been determined to be bacterial cause, or septicemia is a concern.
Possible treatment procedures should be discussed with a veterinarian before the calving season begins. Having a basic inventory of supplies and products as well as a protocol in place will ensure proper early treatment in the course of the disease.
If treatment response is poor, or if there is abnormally high incidence of disease, further diagnostics from a necropsy and results from a Veterinary Diagnostic Lab will help with proper treatment regimens.