Author

Dr. Steve Dudley

Dr. Steve Dudley

Dr. Steve Dudley received his DVM from Kansas State University in 1987.  He is FBN® head of technical services and a practicing veterinarian with Southwest Veterinary Services


Dec 21, 2021

by Dr. Steve Dudley

Dr. Steve Dudley, FBN® head of technical services and a practicing veterinarian with Southwest Veterinary Services discusses scours prevention including pre-calving scour vaccines. Watch now In his presentation, Dr. Dudley discusses prevention strategies, vaccine modes of action, the different vaccines available on the market and how to use vaccines.  Calf diarrhea prevention strategies There are a number of things to consider from a prevention strategy perspective. Keep facilities clean Manure management is crucial when thinking about preventing calf scours. Producers should proactively remove manure from calving areas on a regular basis and provide fresh bedding.  Decrease pathogen load It’s also important to think about different ways to dilute pathogen load. One of the ways to do this is by separating cows into different calving groups and pastures. Another way is to rotate the herd through pastures every 2-3 weeks to keep the calving area fresh. This will decrease the amount of pathogens that older calves are passing to newborn calves. It’s common to see scours increase in severity toward the end of the calving period, so implementing management practices to keep pathogen loads low where new calves are being born is helpful. Stalosan F is a broad spectrum dry disinfectant that can be used in calving facilities. It kills viruses and bacteria to protect animals from infection and disease.   Vaccinate for protection Individual vaccines can be distributed to calves but the most important consideration is good colostrum consumption. Using pre-calving vaccines helps build up the cow’s colostrum and improve the quality of the colostrum. The term, failure of passive transfer, indicates a calf didn’t get antibody protection from the dam. This could be based on not getting enough quantity of colostrum. However, it can also happen when a calf doesn’t receive a high quality of colostrum. Calves get 100% of protection through colostrum consumption.  What makes up a vaccine? Manufacturers all use a similar process to make vaccines. They first determine the antigens or “bugs” (viruses or bacteria) that will be within the vaccine. They then determine and add an adjuvant that presents the antigens to the animals in order to improve the response to the vaccine. Each manufacturer has their own proprietary antigens and adjuvants.  Principles of vaccination Different herds require different vaccines and vaccination programs. There is not a one size fits all perfect vaccine that works in every situation. The differences can be based on: Herd size Geographic area Climate Soil type - sandy vs. muddy Calving operation type - dry lot calving vs. pasture calving Management capabilities  How a mama cow’s protection is passed to calves A cow or heifer is vaccinated and builds up antibodies or protective units to the antigens (bacteria or virus) in the vaccine. Antibodies travel to the udder and become part of the colostrum which the calf then suckles.  Colostrum has a rich antibody environment as well as energy, fat, and nutritional value for calves. It should be noted that 0% of antibodies are transferred to the calf in utero, which means the calf 100% relies on colostrum for protection against bacteria and viruses Colostrum delivery to the calf In an ideal world, calves should receive colostrum within 1-2 hours of birth. The ability to absorb colostrum rapidly declines within 6 hours of a calf’s birth so it is vital that calves receive colostrum as soon as possible. In some cases, it’s important to feed this to the calf via bottle or an esophageal feeder within the first 6 hours of its life.  Pre-calving scour vaccines Three of the most common choices for pre-calving scours vaccines are: and Scourguard® 4K from Zoetis and from Elanco from Merck Differences among pre-calving scours vaccines The table below outlines the differences among the pre-calving scour vaccines. All of the vaccines protect against rotavirus and coronavirus. When a vaccine contains more than one virus strain, it is listed. For example, Scourguard contains two stains of rotavirus - G6 and G10.  The last three columns of the table detail the bacterial pathogens, E. coli K99 and clostridium perfringens, the bacteria known as overeating diseases which cause toxins and sudden death in calves. Proper vaccination is key Proper vaccination will help to maximize the quality of colostrum. It’s recommended that heifers get 2 doses. The first dose should be 10-12 weeks from calving. The second dose should be administered 4-6 weeks from calving (this will allow enough time to get into the colostrum). You do need to consider how long your calving interval is because it can potentially change when to vaccinate.  Cows typically only receive one dose unless the animal is facing additional challenges.  Always administer vaccines according to label directions. It’s important to use clean syringes and replace your needles every 10 cows. Always use a clean needle when entering the bottle. To clean your needles, use hot water and in some cases dish soap can be used. Just be sure to rinse soapy needles very well. Don’t inject wet animals. Moisture can lead to more abscesses and more problems.  Stock up and save on vaccines For more information or to purchase vaccines directly from , please visit our to stock up and save.


Dec 17, 2021

by Dr. Steve Dudley

As cold weather approaches, it’s time to start thinking about lice control in cattle. These parasitic nuisances can cause all kinds of problems from hair loss to reduced weight gain. Watch Dr. Steve Dudley,  FBN® head of technical services and a practicing veterinarian with Southwest Veterinary Services, to learn more about the problems lice create, the different pour-ons available on the market and how to use those pour-ons. Watch now Lice on cattle Lice are the most common external and visible parasites that can present challenges to livestock producers. including irritation and potential loss of production, so preventing and treating them is important.  Clinical symptoms from lice  include: Intense irritation which causes itching and scratching resulting in loss of hair and also damage to facilities and equipment Reduced weight gain Potential anemia from blood loss Types of cattle lice There are two types of cattle lice — biting lice and sucking lice.Biting lice have flat heads and they primarily feed on dandruff and skin debris. They are more difficult to control with problems that are systemic and go through the whole body.Sucking lice have long snouts that feed on blood.  Lice are spread by direct contact but don’t survive long when they’re not attached to animals. Cattle types of lice do not affect humans.  Cattle louse life cycle The life cycle of lice in cattle occurs over a 4-6 week time period. Lice lay eggs on day 1 and by day 7, those eggs have developed. They develop into a nymph stage that lasts for approximately 7 to 21 days. Once a louse reaches the adult stage, it can start to lay eggs in 7 to 14 days and then the cycle starts over again.  Lice are primarily cool season pests that cause more problems in the winter because cattle have thicker coats and insulation.It’s estimated that 1 louse in September can result in 1 million in January if cattle are left untreated. It’s important to proactively treat cattle for lice. Lice pour-ons available  There are several lice pour-ons on the market and we’ve compared a few of the common ones below: (diflubenzuron & permethrin) - this is the active ingredient and there are name brand and generic products on the market (moxidectin) (doramectin) (eprinomectin) Clean-Up™ II is a good product because it offers season long lice control with a single application. It kills all stages of the louse and both biting and sucking lice. It is approved for lactating and non-lactating dairy cattle, beef cattle, calves and horses. It should be noted that Clean-Up II is toxic to aquatic organisms such as fish so you’ll want to minimize any run off when using this product.  The recommended dosage is 3 ml per 100 lbs of body weight and you shouldn’t use more than 30 ml per animal. We recommend that you not only pour it along the back line of the animal, but also on the animal’s poll/face. This may require the person working the headgate to have their own application bottle and gun. The product spreads through the skin via oil. Stock up on lice pour-ons For more information or to purchase lice control products directly from , please visit the to stock up and save.