In JANUARY 2025 – by Dr. Peter Boskamp…

Herpes Virus
Infection with the herpes virus is a common disease in pigeons. Yet generally little is said about it. So it's high time for a closer look.
The herpes virus in pigeons is scientifically known as PHV1. Herpes viruses often cause latent infections. This means that the virus is present in the pigeons without causing any clinical symptoms. Antibodies against the virus can be detected in the blood of more than half of pigeons. We can therefore assume that more than 60% of pigeons are latently infected. This means that they are carrying the virus but are not showing any symptoms. In times of reduced defenses and during breeding, these pigeons may shed viruses again and also become ill.
“Many pigeons are latently infected with the herpes virus”
For a long time, herpes infections in pigeons were treated rather casually. Severe clinical cases of pigeon herpesvirus infection were therefore quite rare. In practice, we have noticed in recent years that there is an increase in clinical infections, and the severity of the symptoms of the disease also appears to be increasing. Reason to be more vigilant in this regard. The increase in infections with the circovirus may play a role, as this virus causes the pigeons' immune systems to function more poorly.
Usually the young animals are infected by their parents at a young age, often during feeding. They still have protection with the antibodies they received from their mother (maternal antibodies). Therefore, there are usually no clinical symptoms. They remain infected for life.
Pigeons that do not have antibodies are expected to experience clinical symptoms as soon as they become infected with the virus. This can happen, for example, with purchased young pigeons that are housed with your own young pigeons. Symptoms of the disease may appear after 5-7 days. If the virus multiplies heavily, the infection pressure in the loft can become so high that even young pigeons with few antibodies show symptoms of illness. In this way, the virus can remain active in the field for a long time. With all the consequences that this brings with it for the young pigeon racing season. Recovery from a more serious viral infection can take one to three weeks.
In stressful situations, such as when being transported in a basket, carriers can excrete these herpes viruses. Of course, this happens more quickly if the pigeons' resistance is low.
Studies in Germany have shown that a peak in virus shedding during transport occurs in July and up to 60% positive fecal samples are found.
As already mentioned, the importance of the herpes virus in young pigeons seems to be increasing. In particular, young pigeons between the 2nd and 10th weeks can show clinical symptoms. The clinical symptoms are very different. From acute mortality with significant losses in young pigeons to the more well-known conjunctivitis, which we then call “the membrane”.
Symptoms
If we list the entire picture of symptoms here, it must be taken into account that this only occurs as such in a limited number of cases. Often only a fraction of these phenomena can be observed. This sometimes makes diagnosing a herpes virus infection difficult based on clinical symptoms alone. Very typical herpes symptoms are manifested by yellowish deposits in the mouth and throat. These deposits form a loose film on the mucous membrane of the mouth, tongue and throat, in contrast to diphtheric deposits or deposits caused by very severe yellow infections (which now only occur very sporadically). The virus primarily affects the upper respiratory tract and the mouth and throat, as well as the trachea, goiter and esophagus. Due to the damage to the throat, the pigeons can hardly digest the food and their appetite almost completely disappears. Although it is mainly a condition that we see in pigeons between two and ten weeks of age, these symptoms can also occur in older pigeons. In severe outbreaks, more than half of the pigeons can die as a result of the viral infection. The extent to which the symptoms appear also depends on the resistance of the pigeons and certainly on the strength (virulence) of the virus. The latter fluctuates quite a bit, so the extent to which the phenomena occur can be different every year. We often only experience mild symptoms; sometimes the only thing we see is the membrane in front of the eye or a yellow-gray discoloration of the nose caps. But also diseases in which severe complaints of the upper respiratory tract and damage to the sinuses and alveoli occur. If there are only a few antibodies in young animals, a general infection with liver damage can occur.
Other diseases in which we can find deposits in the mouth are trichomonas, smallpox, diphtheria and candidiasis (fungi). And occasionally dried mucus after a hard flight. In smallpox, diphtheria and trichomonas, the coatings are more like cheese and therefore have a different appearance.
“With a herpes infection there are often only a few symptoms”
Since the majority of herpesvirus infections are still relatively mild, the role of this virus in the entire ornithosis complex is of particular importance. There is little that can be done against the virus itself. If the infection is serious, pigeons will be given preventive medication to prevent them from succumbing to further infections. In valuable pigeons, an attempt can be made to lessen the severity of the disease and somewhat limit the influence of the virus by administering acyclovir for around ten days. You shouldn't expect miracles. In addition, if pigeons are severely affected, individual animals can be supported, for example with Synulox tablets. In the event of a herpes virus infection, it may be useful to disinfect the loft with Koudijs dry disinfectant or with the biological nebulizer. It is possible that in this way the infectious pressure of the virus is slightly reduced by reducing the amount of free-floating virus particles. Some (alternative) publications state that nebulization of certain essential oils is effective against the number of virus particles in the air.
Diagnose
The diagnosis is therefore mainly based on the clinical symptoms and the fairly typical lesions in the mouth. Virus isolation is rarely carried out under practical conditions as it can only be carried out in a few specialized laboratories.
It is important to correctly detect secondary infections because infection with the herpes virus makes pigeons more susceptible to infections with coli, staphylococci, streptococci, etc. These then need to be addressed.
As already mentioned, the herpes virus plays a major role in the entirety of young pigeon syndrome and the ornithosis complex. Since medications are available against some pathogens of the ornithosis complex, many pigeon breeders tend to assume that medication can also be used to combat the herpes virus. This is a persistent misunderstanding that can sometimes lead to considerable frustration among breeders. Giving medication to a predominantly herpes infection can definitely make sense in order to prevent further infections from getting worse. But it is and remains an illusion to believe that we can cure this viral infection with antibiotics.
It is now clear to the attentive reader that this infection is also primarily about prevention. In this case, prevention also means that we have to ensure that the resistance of the young pigeons is kept as high as possible so that the pigeons themselves can recover from the virus infection as quickly as possible. However, it is not the case that when you give preventive agents such as Bony SGR or Bony Sambucca Plus you can be sure that you will remain free of herpes viruses or other viruses. This ensures that the pigeons are given the right tools to deal with these attackers themselves. In practice, recovery from these infections will certainly be accelerated.
There is often frustration at the boys' poor results. There is often little or nothing to be seen in the young animals. The course of the flights and the behavior of the young animals often indicate a herpes infection if other causes are ruled out. So peace and quiet would be the order of the day. Given the flu among participants, people should not participate in a running race. But most fanciers still want to play the young pigeons that seem good. Of course, what is to be expected happens: the boys don't come home or fly home way too late. Even if only the boys were accommodated there, “where there was nothing to see”.
Of course, we are often confronted with this complaint during the young pigeon season. In such cases, calm and common sense help more than gambling that “maybe it’s over”. Because this will only destroy the young even more and waste them unnecessarily.
Our advice for (herpes) virus infections during the travel season:
1. Preventively keep resistance as high as possible before the season, for example by giving Bony-SGR.
2. Keep the infection pressure of secondary infections on training flights as low as possible.
3. In case of a herpes virus outbreak. Give the pigeons rest and let them get sick.
4. Provide medications as needed to prevent attenuation of secondary infections.
5. Then train the pigeons yourself to avoid unnecessary losses.
Good luck!

Dr. Peter Boskamp

"Regular health check is the basis for good aerial race results in the pigeons"
Pigeonvetcenter
For a long time, thePigeonvetcenter under the direction of Peter Boskamp located in the Limburg Beek. The Pigeonvetcenter is a department of Diergeneeskundig Centrum Beek. In this center to work today6 veterinarians / veterinarians and 5 veterinary assistants.
In thePigeonvetcenter They receive professional veterinary support on all aspects of pigeon sport. The following services can take:
- Control and medical monitoring of their pigeons
- Vaccinations (O.A. paratyphoid, smallpox, paramyxovirus)
- faecal; Fecal samples can be sent by mail
- Parasitological examinations (O.A. coccidiosis, worms, etc.)
- Bacteriological tests (O.A. Salmonella, E. coli, etc.)
- Virale Untersuchungen (o.a. Paramyxo, Adeno etc.)
- mold tests
- chlamydia tests
- Blood tests
- Fillet and Kloakensabstriche
- fertility treatments
- Operations
- Section
- Hospitalization and Beaobachtungen
- X-RAY DIAGNOSTICS
You can find more information about study opportunities inwww.pigeonvetcenter.com.
