Newsletter November 2011

The Adenovirus

In the past few weeks a number of lovers asked me if I could pay some attention to the previous named virus. One of these lovers got this diagnose from a colleague vet, another lover reported that this had to be the Adenovirus. Surely, his pigeon showed all symptoms which suggested the Adenovirus. Even in our clinic, we had to tell some lovers that we diagnosed some pigeons with the Adenovirus. The definite diagnosis can be established at dissection of the pigeon and especially through pathological research which showed liver necrosis. In doubtful cases, some of the material had to be sent to a laboratory to seek assurance. Therefor valuable time is lost. Fortunately there are

Peter Boskamp

nowadays practical and useable tests to confirm in just a few minutes the presence of this virus through a cloaca-swab. Similar test are available for a number of other virus which occur in the pigeon community. Through these tests, the diagnostic possibilities in the clinic are significantly improved.

The lover who diagnosed the Adenovirus only on the clinical signs, is on a slippery slope. There are multiple diseases which some similar symptoms of the Adenovirus. Recently there was a lover in the clinic who was sure his pigeon were infected with the Adenovirus. The pigeons died fairly quick. In addition, the lover was treating the pigeons against paratyphoid for 14 days, with a known cure. This was something he always did in this time of year. With this history it is easy to fail. Because, with the treatment against paratyphoid in mind, it is easily assumed that paratyphoid is not the cause. We were offered a pigeon for necropsy. In the history was told that the pigeon died that same day. It is logical to cut this pigeon open, and not the pigeon that looked reasonably well, even though skinnier. The dead pigeon showed inflammation lesions in kidneys and the intestinal wall and the liver was mottled. Less than 24 hours later, in all three places was paratyphoid found, even though the pigeon received a paracure long-term.

This incident shows that confirmation of paratyphoid is not as black-white. We have to approach this as a complex problem, what it is essentially. On several areas at the same time, there has to be take action. On one hand, increasing resistance, on the other hand vaccination, good disinfection and the right medication is important. Given that the resistance of the bacteria against several antibiotics is increasing (it cannot be excluded that this is the effect of needless and unnecessary treatment against this bacteria without the right knowledge, with too short treatments and the wrong medications) it is wise to conduct an antibiogramme before the start of the treatment of Salmonella Typhimurium.

Nonetheless, this newsletter is about the Adenovirus. The Adenovirus occurs more in spring time than in the fall. We have to distinguish two separate strands of the Adenovirosis: Type 1 and Type 2.

The problem that seems to be showing nowadays is more likely to be attributed to Type 2. In the spring time, it is wiser to discuss Type 1, a classic image at young pigeons, when this type reaches its peak.

Adenovirus Type 2.

This virus occurs throughout the year and can affect pigeons at any age. In contrary to Type 1, there are few signs of Type 2 because the pigeons die very fast. Often within 12-24 hours.

At necropsy, the results are often severe liver necrosis. This is the main reason of the quick death of the pigeons. Even if there are symptoms, these could be incidental vomiting and yellow, liquid manure. The mortality amongst the pigeons can be great in numbers, but it could happen that the pigeons die slowly and over a few weeks with incidental deaths.

When the pigeons die slowly over a number of weeks, there is often a second bacterial infection. The bacteria found in the bacteriological research are most likely E. Coli, Streptococci (Streptococcus gallolyticus) or Staphylococcus (Straphylococcus intermedius).

We have to be careful not to blame this virus when the pigeons die suddenly. Because Streptococci can cause sepsis and immediate death, but Salmonella and E. Coli show the same symptoms. This is often the reason why antibiotics are administered when there is death amongst the pigeons. When the source of these deaths is known and it is the Adenovirus, antibiotic does absolutely nothing against this virus. The only thing these antibiotics do, is help the pigeon fight of the secondary infection. Be aware of this, because heavy antibiotics put a strain on the liver, so you put the cart before the horse.

Typical is that there are pens where there are a lot of deaths among the pigeons, but there are pigeons who are not affected by it all. Even parents can die, but their offspring are not at all affected.

Preventive vaccination is unavailable. The spread of the virus can be reduces by keeping the infection pressure low and increasing the resistance.

When I come across an Adenovirus infection, I prescribe Bony Sambucca Plus for a fortnight, combined with a mild antibiotic if this seems necessary. To support the liver, Sedochol, Biochol of Bonichol is effective.

Good luck,

Peter Boskamp