VACCINATIONS FOR KUNEKUNES
By AKKPS Member Debra Allen of Allen's Acres
WHY SHOULD YOU CONSIDER VACCINATING YOUR HERD
Having healthy animals is the goal of every KuneKune owner, however keeping animals healthy requires a good herd health management plan.
Protecting your pig farm from entry and spread of diseases is critical. Sometimes, despite excellent biosecurity and animal husbandry, pigs can become infected by a disease transmitted by humans (such as human influenza), from the sow (such as circovirus), or from other pigs and vectors. Vaccines prepare your pigs for that possibility by priming their immune system in ways that help them fight off or neutralize the disease or its effects, thus minimizing damage it may cause to the lungs, intestines, or other critical organs. Most commercial vaccines widely used in pigs have consistently demonstrated excellent efficacy against the bacteria or viruses they target. In surveys designed to determine pig disease cost (due to lost performance, death, or treatment) versus the cost of disease prevention by vaccines, the reported benefits of vaccines consistently exceed their cost by at least 2.5:1 (Miller & Dorn, 1990; Niemi et al., 2018).
There are other important reasons for using vaccines to protect your herd. First, kunekune breeders are committed to the well-being of their animals, so it makes sense for them to prevent diseases before their animals contract them. For example, the disease erysipelas will cause a high fever and lesions on the skin. As a result, pigs go off feed and some experience pain in the joints. These conditions are fully preventable by vaccinating against erysipelas. Second, vaccines reduce the number of pigs that will contract diseases such as erysipelas and influenza that can be transmitted to and cause disease in humans. Third, preventing disease by vaccination usually allows animals to be raised using fewer antibiotics, including those that are medically important. Reducing large-scale use of antibiotics helps prevent the emergence of antimicrobial-resistant strains of pathogenic bacteria and fungi. This is critical for preserving the long-term efficacy of those agents for future use in both animal and human medicine.
Diseases that infect pigs can enter the farm in many forms, including through other pigs, contaminated feed, delivery trucks or equipment, rodents and other wildlife, and people. They can also come in attached to dust particles that blow in from neighboring farms. These sources of disease are almost impossible to eliminate entirely. However, in many infectious diseases, the infectious dose (amount of virus particles or bacteria required to cause disease) largely determines the disease outcome. An infectious dose can be reduced dramatically by consistently practicing preventive farm biosecurity measures.
BIOSECURITY ARTICLE (click here)
HOW DO VACCINES WORK?
All animals have various defense mechanisms to prevent or deal with infections. The defense mechanisms of the animal can be directly influenced by age, nutrition, or inappropriate management practices. Stress due to heat, weaning, malnutrition, infection, transport, and other factors can impact how the immune system reacts to a pathogen attack. An important component of any herd health plan is a vaccination protocol.
Most vaccines induce protection by priming the system to mount an antibody response. When an animal has not been exposed to a specific pathogen or comes in contact for the first time, it can be slow to develop antibodies. Most vaccines work by introducing the body’s system to pathogen-specific proteins. Often, without this “sneak preview” of the vaccine, the animal cannot generate an immune response quick enough to clear or destroy the pathogen, making the animal susceptible to the agent and becoming sick. However, if the animal has a robust immune system or has been vaccinated, it will suppress the pathogen and, in time, clear or significantly reduce the infection.
When an animal recovers from disease or has been vaccinated, specific cells from the immune system will acquire the ability to remember and recognize the pathogens (virus, bacteria, toxin, or parasite) or parts of the pathogen known as antigens. The next time the immune system recognizes these antigens, it will immediately trigger the production of specific antibodies by specialized cells, which will work to destroy the pathogen.
Vaccines expose the animal to parts of pathogens (whether viral or bacterial or other) by challenging the immune system to react to a possible invasion by creating memory cells for the antigens belonging to that specific pathogen. In the future, if the animal is exposed to the same pathogen, the immune system will quickly generate a response before the pathogen can cause disease. Each antibody is usually specific for only one antigen. Because of this, the immune system keeps a supply of millions of different antibodies on hand to be prepared to overcome any foreign invader. For a naïve animal (an animal that never was exposed to the pathogen), it may take 7 to 14 days after exposure to an infectious agent for the body to develop immunity to an antigen, which is plenty of time for some pathogens to wreak havoc on the body. On the other hand, it often takes only 48 hours to mount an immune response to the same antigen in a vaccinated animal.
There are several types of vaccines used in humans and animals. The majority of the licensed veterinary vaccines currently in use are inactivated (killed) vaccines, live-attenuated vaccines, or toxoids. All these represent different strategies used to reduce the risk of illness while retaining the ability to induce a beneficial immune response.
TYPES OF VACCINES
Attenuated vaccine: Some vaccines contain live, but altered microorganisms. Many of these are active viruses cultivated under conditions that disable their virulent properties or use closely related but less dangerous organisms to produce a broad immune response. Although most attenuated vaccines are viral, some are bacterial. Attenuated vaccines have some advantages and disadvantages. Attenuated, or live, weakened, vaccines typically provoke more durable immunological responses. But they may not be safe for use in immunocompromised individuals.
Inactivated vaccine: Some vaccines contain inactivated but previously virulent microorganisms that have been destroyed with chemicals, heat, or radiation. They are considered an intermediate phase between the inactivated and attenuated vaccines. Examples include IPV (polio vaccine), hepatitis A vaccine, rabies vaccine, and most influenza vaccines.
Toxoid vaccine: Toxoids are made from inactivated toxic compounds produced by microorganisms that, when activated, cause damage to cells. Examples of toxoid-based vaccines include tetanus and clostridium. Not all toxoids are for toxins created by microorganisms; for example, Crotalus atrox toxoid is used to vaccinate dogs against rattlesnake bites.
Subunit vaccines: These vaccines contain short, specific proteins that are the same as the antigens of the target pathogen. A subunit vaccine uses a component to induce an immune response rather than introducing an inactivated or attenuated microorganism to an immune system.
Conjugate vaccine: Certain bacteria have a polysaccharide outer coat, which is a weak antigen. The immune system has a more robust response by linking these outer coats to proteins (toxins), which are strong antigens.
Outer membrane vesicles (OMVs): OMVs are released spontaneously during growth by many groups of bacteria. They have the ability to naturally provoke an immune response in the body of a human or other animal and can be manipulated to produce potent vaccines. The best known OMVs vaccines are those developed for serotype B Meningococcal disease.
Heterologous vaccines: These are also known as “Jennerian vaccines“. The heterologous vaccines contain pathogens from other animals that either do not cause disease or cause mild illness in the organism being treated. The classic example is Jenner’s use of cowpox to protect against smallpox. A current example is using the vaccine made from Mycobacterium bovis to protect against tuberculosis in humans.
Viral vector vaccines: This vaccine uses a nonpathogenic virus to insert pathogen genes in the body to produce specific antigens, such as surface proteins, to stimulate an immune response. The new EHDV vaccine uses this technology in combination with the subunit vaccine technology.
RNA vaccine: A mRNA vaccine is a novel type of vaccine composed of nucleic acid RNA, packaged within a unique delivery system like lipid nanoparticles. Several COVID-19 vaccines are RNA vaccines and have received emergency use authorization in some countries.
Vaccination is only one tool to prevent disease and cannot be used as a standalone practice to prevent disease or infection on the farm. Vaccination does not result in immediate immunity or resistance against diseases in all vaccinated animals. It takes time for the animal’s immune system to react to the vaccine. Therefore, if an animal is vaccinated, it does not automatically mean that the animal cannot be infected or develop the disease. The degree of protection is directly dependent on the animal’s health, how well the vaccine is matched to the pathogen, and how well the vaccine is administered to the animal. Vaccines come in many types, but all are delicate organic products that need to be managed and administrated correctly to ensure their effectiveness.
VACCINE STRATEGY
No single vaccine strategy fits all farms. Disease risk can vary based on geographical areas and pig flow patterns, including entry of new stock. Also, vaccine selection and dose regimen are often dependent on pig age and breeding status. Gilts are typically vaccinated prior to farm entry and again prior to breeding because they may be naïve to current diseases on the farm. Vaccines can provide a quick immune response including antibodies in the colostrum that are passed from the gilt to their first litter. Because maternal antibodies wane in the first 2 to 3 weeks after birth, piglets will likely require another vaccine at weaning. For these reasons, the best advice regarding vaccine products, dosage, and timing, along with information on the risk of specific diseases in your area, will likely come from your veterinarian. It is also useful to consider information provided by your vaccine supplier, mentor, kunekune breeder, feed mill employees, and other local pig farmers.
IMPORTANT FACTORS TO CONSIDER WITH VACCINES
Your vet can help identify which diseases are reliably preventable with vaccines and how to obtain the best options for your farm. It is recommended that you and your vet work together to develop a vaccination strategy that includes such information as: • Disease • Vaccine • Vendor(s) • Dosing schedule • Amount, site, dosing procedure • Possible injection site reactions to be prepared for • Required withholding periods. Record this information (as a standard operating procedure, or SOP) and review on a regular basis with your vet to ensure that the plan is up to date. This SOP should be readily accessible to you, farm staff, and anyone else who may need to fill in for you and provide care over an extended period.
Before giving vaccines, read the dosing instructions on the label and confirm the expiration date. Record the day’s date, pig ID, vaccine administered, lot number, expiration date, dose volume used, and the name of the person delivering the vaccine. Pigs should be healthy at the time of vaccination. Don’t vaccinate an animal running a fever. Make sure the intended injection site is clean. Most vaccines have withdrawal times; usually this period is 21 days following injection. This information is clearly stated on the product label and must be followed. Be aware that efficacy of some live vaccines can be compromised by pre- or co-administration of certain antibiotics.
Zinc deficiency can also compromise vaccine efficacy by virtue of the immunesupporting effects of this trace mineral. Your veterinarian will be able to answer questions regarding withdrawal time requirements and possible interactions between vaccines and antimicrobials or trace minerals.
Most vaccines currently used in pigs are administered into muscle (IM) or just beneath the skin (SC) a few inches behind the ear; a few can be administered intranasally (in the nose) or in water, which can be affected by water treatment protocols. The proper needle size (gauge) and length is based on stage or size of the pig. It is recommended to use disposable needles when possible. Plan to use each needle no more than once, and discard used needles in a container marked “sharps,” designed to prevent needles from spilling out if the container is dropped or turned over, and it prevents an individual from being accidentally jabbed with a used needle.
Order vaccines from a trusted source. Always order from a trusted veterinary supplier or directly from the company producing the vaccine. If vaccines are to be shipped, verify proper temperature controls will be used, such as ice packs or foam containers.
Order an adequate amount of vaccine. Always add an extra 10 percent to your order to account for possible vaccine losses during animal handling especially if using an aid like a ‘Slap Shot’. If possible, order bottles with fewer doses. Shelf life varies for each type of vaccine. Some vaccines have hours of efficacy after being mixed, some longer. However, it is not recommended to use an open vaccine bottle kept in the refrigerator after long periods. Again, fewer dose bottles help calculate what you need for that day.
Correct storage conditions. Check instructions on how the vaccine should be stored. Most animal vaccines require refrigeration at 35 – 45 ˚F (2 – 7 ˚C). Make sure your storage refrigerator works properly, place a thermometer in a prominent place so you can check the temperature often. Refrigerators held in barns or open sheds can have temperature variations throughout the day, affecting the temperature. Never freeze a vaccine, nor let it get too warm. Always avoid direct sunlight on your vaccine.
Expiration dates. Always check expiration dates, and always start by using the oldest first. Once opened, always label the bottle with the date, particularly if you will store it for later use.
Correct preparation and vaccine shelf life after mixing. Follow directions on the bottle to ensure its effectiveness. This is very important; some vaccines need to be reconstituted with sterile water or have components that need to be mixed. Make sure you follow the instructions and always mix gently. Remember, vaccines are delicate organic products. Prevent temperature shocks. Grabbing a cold vaccine bottle with warm hands can rapidly change the container’s temperature and affect its efficacy.
Exposure to UV light. Do not expose vaccines to Ultraviolet light from the sun. Some vaccines can be rapidly deactivated if exposed to UV light.
Emergency information. In case of an accidental human injection or exposure to the vaccine, it is always important to have emergency numbers at hand for everyone working on the farm.
EXAMPLE OF VACCINE PROTOCOL
ALWAYS ASK YOUR VET FOR RECOMMENDATIONS FIRST
Piglets: Circoflex at 3 weeks, Rhinishield TX4 at 5&7 weeks
Meat pigs: Rhinishield TX4 every 6 months
Pigs 6 months to breeding age: Rhinishield Tx4 every 6 months plus Circoflex once a year
Breeding boars: Circoflex once a year, Farrow sure Gold every 6 months.
Breeding gilts&sows: Circoflex once a year, Farrow sure Gold per direction or every 6 months.
Bred sows: Rhinishield Tx 4 at least 6 weeks before the due date.
In conclusion, this article provides a basic guide that can help you to better understand the basic mechanism and types of vaccines available, as well as some basic best practices of vaccine management. This information can help you be successful in your next herd vaccination to guard the health of your kunekunes. In the US, animal vaccines are regulated by the United States Department of Agriculture (USDA), and further information about licensed vaccines can be found on their website:
USDA Animal Health – Veterinary Biologics.
Most important diseases that infect kunekunes, including those caused by pathogenic viruses and bacteria, can be prevented or their effects reduced by vaccines. Along with a sound biosecurity program, vaccines are the most cost-effective tool for preventing serious disease outbreaks on your farm. In most circumstances, vaccines are effective only when administered before exposure occurs to the specific pathogen it targets. The type of vaccine and dose regimen used can be highly dependent on the stage of pig development, and whether the animal involved is a breeding or nonbreeding animal. Always administer vaccines according to the manufacturer’s recommendations and be aware of withholding times for some vaccines. Your vet is the best source of information to consider when developing a vaccination strategy for your farm.