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Maintaining a high level of herd health is a never-ending job. That’s because even with sound healthcare techniques and good biosecurity, the health status of a swine population is dynamic. A program of systematic surveillance is essential if an operation is going to improve the herd’s overall health status, quickly recognize emerging health challenges, lessen the impact of diseases and make herd healthcare more cost effective.

 Observations And Performance Analysis

The importance of daily observation of pigs of all ages can not be overstated. Employees should be strongly encouraged to be good pig watchers who take pride in being able to recognize developing problems early. Unusual behavior is often the first sign of a new disease challenge.

A systematic method of observing all pigs in all buildings needs to be developed. In addition to watching closely for clinical signs of diseases like coughing or lameness, floors, walls and pen dividers should be inspected.

Daily observation should include a quick check of feeders and waterers to make certain they are functioning properly.

A drop in feed and/or water intake is often one of the first indications the health status of a group of pigs is changing for the worse. Several baseline indicators should be established and monitored closely. In addition to feed and water disappearance, these might include things like the number of treatments and mortalities per week.

It’s also important to occasionally bring in an expert set of eyes and ears from outside the operation. A veterinarian should periodically conduct a walk-through evaluation of all phases of production.

A good set of production records is another important aspect of monitoring herd health. Frequent analysis of performance trends from the various phases of production can provide warnings a chronic health problem either has or is developing.

Lab Work

Monitoring a swine population for specific disease agents establishes a health baseline and provides extremely valuable information when trying to determine the cause and severity of a health problem.

Random sampling with a focus on the breeding herd and finishing units is usually recommended for routine blood work.

Unless addressing a specific or emerging problem, serum profiling of young pigs is usually not recommended. That’s because maternal antibodies can produce false positive readings for some diseases. In certain situations, however, taking blood samples from pigs of all ages will provide clues about when disease organisms are being transmitted or are becoming active.

Serology helps pinpoint the presence of several pathogens. Over time, a herd’s serological history and profile can be developed. Keep in mind, however, that such a profile is really just a snapshot of the current status.

Blood work is extremely important for incoming breeding stock. All new herd additions should be serum profiled and this information compared to the operation’s existing health status. This information should be used to protect the health of animals already in production and to acclimate new stock to organisms present in the existing herd.

Bacteriology is another valuable diagnostic tool. Lab samples can often be used to identify bacterial cultures that are causing respiratory and other problems. Once a culture has been obtained, not only can bacterial pathogens be identified, antibiotics sensitivity tests can be run. Sampling pigs of different ages will also provide clues about the distribution of pathogens throughout the population.

The polymerase chain reaction (PCR) test is used to detect both bacteria and viruses. This test looks for the DNA of specific disease agents.

Once a herd’s disease profile is known, a comprehensive program can be developed that matches the disease challenges that are present. Routine lab work will help make medication programs more effective both in terms of disease control and cost.

Postmortem Exams

Accurate death records are essential when assessing the overall health of a swine population. The date and number of deaths is obviously important information.

It is also extremely important to try to determine the cause of unexpected deaths.

However, because a combination of factors often leads to an animal’s demise, it can be difficult to pinpoint the exact cause of death for individuals. Therefore, it’s sometimes more important to study patterns than the cause of one or two deaths.

This is certainly not to say the first death in a group of pigs or in several weeks should be ignored. A postmortem exam of that first death could provide invaluable information that will head off a major problem before it gains a foothold.

There are also times when sacrificing a few animals for examination is necessary to determine exactly what disease organisms are at work. Keep in mind, however, that as an animal nears death its immune system breaks down. This can make it difficult to identify the most troublesome health issue. Therefore, pigs that are still relatively healthy often provide more valuable information.