Health-related problems are silently stealing profits from growing-finishing hogs on many swine farms. Although acute death loss and sick hogs are not difficult to see on the finishing floor, the effects of chronic disease in these hogs may not always be readily apparent. To avoid both acute and chronic disease problems in the grower-finisher, a swine operation should strive for "high health status." To accomplish this, pay attention to the following points.
All-In All-Out Production
Recent research has firmly established that a "true" all-in all-out system during the growing-finishing period improves performance. This improvement amounts to a 5 to 10 percent increase in daily gains, resulting in fewer days to market. Feed efficiency also improves 5 to 10 percent. All-in all-out production is widely practiced in the large swine farms that are continually evaluating their production performance and their costs. They know it works for them, and it can work for the smaller producer also.
"True" all-in all-out performance means keeping pigs together from farrowing to finishing in groups ranging no more than 2 weeks apart in age. As pigs grow they should not have nose-to-nose contact with older hogs. The best way to accomplish this is to put solid partitions between pens, with separate rooms being even better. All-in all-out works because the disease-causing organisms (viruses, bacteria, mycoplasmas, etc.) are usually spread from animal to animal. Younger pigs, especially those moving into the grower from the nursery, have less well-developed resistance to diseases. The older hogs that they may contact during grow-finish are likely to spread such organisms to them, especially those causing respiratory diseases. The older hogs have already been exposed and have become somewhat resistant. In the process, however, hogs may undergo bouts of disease that can set them back and increase days to market. Keeping pigs together in close age groups prevents exposure to disease-causing organisms from older hogs and avoids setbacks.
An inherent part of "true" all-in all-out is the marketing of hogs from a pen as few times as possible. It is best to market from a pen twice, the second time clearing it out. The practice of "sorting back" hogs that are doing poorly should be avoided. This defeats the purpose of keeping hogs of close age groups together. Hogs doing poorly are also often disease-carriers and should not be exposed to younger hogs.
External And Internal Parasites
External parasites such as lice and mange mites can decrease feed intake and gains significantly. Fortunately, these parasites can be controlled with routine treatments. Chemicals to delouse and treat for mange should be sprayed when hogs move into the grower and again 2 weeks later to help break the parasites' life cycles. Alternatively, an injectable dewormer, ivermectin, will treat mange mites and sucking hog lice as well as treat internal parasites (worms).
Internal parasites such as roundworms can cause sizable production losses by damaging liver and lung tissues. Other internal parasites such as kidney worms may be major problems in hogs on dirt lots or pasture. In total confinement grower-finisher units these worms are usually less of a problem. However, if sanitation is not good and feces builds up, roundworms can be significant factors in lowering production in confinement units. The amount of feed required for a pound of gain can be significantly increased as parasite loads become heavier (Table 5, below). Establish a good sanitation program to help prevent worms from becoming robbers of productivity Washing sows' and gilts' underlines before moving them into the farrowing crates will also help reduce transmitting parasites to newborn pigs in the crates.
Parasite Load | ||||
Parasite |
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| Threadworms |
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| Kidney worms |
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| Whipworms |
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| Large roundworms |
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Most modern dewormers will help control roundworms. Many dewormers can be administered in the feed, while others may be injected. Some, such as pyrantel tartrate (Banminth) and hygromycin B (Hygromix) can be fed as preventatives for long periods of time but may be less cost-effective depending on duration of treatment. These may be more effective in swine finishing on dirt. Rotation of pasture or drylots may help reduce reinfection with internal parasites after deworming.
Deworming programs should be based on the amount and type of parasites present in your herd. Your veterinarian can perform fecal flotation exams of fresh manure samples for presence of worm eggs. It is best to do fecal exams on young pigs shortly after they move into the grower. Some operations may need only sows to be dewormed before each farrowing. Others with heavier worm burdens may require more frequent deworming during grow-finish. Slaughter checks can also determine if worm larvae migration through the liver is causing significant problems. Your veterinarian can also be looking for lung worms and kidney worms. If these parasites are found on fecal exams or at slaughter checks, consult with your veterinarian about appropriate dewormer to use.
Sanitation
All confinement growing-finishing pens should be cleaned and disinfected between each group of pigs. By practicing all-in all-out production in the grower-finisher you can accomplish this in an empty room or building. You can reduce the incidence of many diseases found in growing-finishing hogs by cleaning with a high pressure sprayer and then treating with an effective disinfectant. A listing of common disinfectants and their uses is in the Pork Industry Handbook (PIH-80, "Selection and Use of Disinfectants in Disease Prevention"). When roundworms are present in growing-finishing pigs in confinement, cleaning should be followed by a 2 percent lye solution that will remove roundworm eggs from concrete floors.
Veterinary Visits And Consultations
Establish a relationship with a veterinarian who is knowledgeable about swine diseases and interested in the swine industry. Your veterinarian can make periodic slaughter checks of your hogs to see what diseases are occurring during the last 4 to 6 weeks of production. Examination of the livers, lungs, and snouts can provide a good indication of the effectiveness of your health program. If your veterinarian cannot conduct periodic slaughter checks, some slaughter plants can arrange to have it done by a veterinarian in the area. It is best to examine at least 30 hogs or a number according to a statistical table based upon the type and amount of disease that is suspected to be present. It is desirable to check the "middle of the road" finishers in a slaughter group.
Your veterinarian should also conduct necropsies (autopsies) of any hogs that die unexpectedly, in order to reach a good diagnosis of the cause. Your health program should be designed to avoid death loss. If losses occur, you need necropsies performed in a timely fashion in order to take appropriate action. Feed, water, or injectable medications should be used based upon a good diagnosis, whenever possible. Your veterinarian should be involved in your routine herd-monitoring program. He or she can be invaluable when evaluating health-related changes in feed intake and conversion and growth. Details on establishing a herd-monitoring program are in Circular ANR-673, "Swine Herd Monitoring."
Antibiotics And Residue Avoidance
Medicated feed can be included at three different levels: performance improvement, disease prevention, and disease treatment. For example, chlortetracycline may be fed at 10 to 50 grams per ton of feed for growth promotion and improved feed efficiency, at 50 to 100 grams per ton of feed for the prevention of bacterial enteritis (scours), and at 100 to 200 grams per ton of feed for the treatment of scours.
Growth-promotant antibiotics can improve nutrient usage and gain and feed efficiency in growing-finishing swine. These products may act directly on the pig's growing tissues, alter the bacterial population of the intestinal tract, or reduce "low grade" disease problems. Consult the Pork Industry Handbook (PIH-31 "Feed Additives for Swine") for more information.
Water medications are preferred for treatment of some diseases because sick hogs will often drink when they will not eat. This is particularly useful in newly arrived feeder pigs. Observe hogs carefully during water medication, however, to insure that there is no decrease in water intake because of the flavor of the water.
Individual pig treatment is sometimes necessary, in particular with diseases that can cause death rapidly. Injecting an appropriate antibiotic may be the only effective way to treat such animals, despite the labor intensive nature of the treatment. Diseases such as Actinobacillus (Hemophilus) pleuropneumonia and salmonella cholerasuis are two examples of diseases that may require such medication. In these cases, mark injected pigs with a crayon and treat for 3 continuous days to insure proper duration of therapy. Consult with your veterinarian on the proper type and doses of injectable antibiotics.
It is very important to check the labels of all medications used, whatever their route of administration. Some producers are guilty of under treating when they do not include the proper amount of antibiotic in feed or water. It is critical to follow the drug label's withdrawal period before slaughter. Drug residues can be a major problem if drugs are not used carefully, resulting in carcass condemnation. Make sure that medicated feeds are followed with non-medicated feed to "flush" the feeders, mixers, and other feed-handling equipment. It may be necessary to wash equipment before using it for non-medicated feed.
Proper use of pharmaceuticals is essential to insure the quality of pork. Detailed records of individual animal treatment and feed additive use must be kept and followed to prevent future pork quality problems. The National Pork Producers Council sponsors the Pork Quality Assurance Program (PQA), which is an integral part of the Alabama Swine Herd Monitoring Program. This is a three-stage, self-help program to help pork producers improve the quality of pork. The PQA manuals contain useful information on feed additives, injectables, and water medication. They also contain sample record sheets for monitoring individual animal treatments and medicated feed production and use. Participation in the program is voluntary but may be required by some marketing groups and markets. Information is available from the county Extension office or the Alabama Pork Producers.
Control Movement Of Visitors
Despite all the efforts to keep a farm free of particular diseases, they can break down in a few minutes if flow of people and vehicles is not closely controlled. This is particularly true in areas where there are nearby hog farms. Feed delivery trucks, repairpersons, sales agents, and veterinarians have been unwitting transmitters of disease. Insure that clean cover-alls and rubber boots are available for visitors, along with disinfectant foot baths. It is even more effective to deny entry to all except visitors whose presence is critical. Some high health farms practice shower-in shower-out routines to prevent disease entry.