RESPIRATORY COMPLAINTS AND WHAT TO LOOK FOR IN POULTRY.

eye infections4picture courtesy of backyardchickens.com

THERE ARE SO MANY RESPIRATORY DISEASE THAT LOOK THE SAME IN POULTRY, SPECIFICALLY CHICKENS. HOW DO YOU KNOW WHAT YOU ARE DEALING WITH?

Here are some ideas. I hope they help:

INFECTIOUS CORYZA

This is very common. It is a bacterial infection that birds contract mainly from wild birds and then from each other.

Coryza affects adult and half grown birds.It can be chronic, that is it can repeat again and again if the problem is not dealt with energetically. It is caused by a bacterium known as hemophilus gallinarum.

Symptoms are:

Swollen sinus. Discharge  from nose and eyes. Closed eyes, watery eyes, discharge sometimes yellow/green if the infection is bad. The discharge has a putrid smell, and birds rub their heads to clear the sinus, making a tell tale pattern of soiled feathering around the neck. Birds cough, sneeze, and can have a fever. they will be off their feed, and listless, pale. They will infect any bird that comes in contact with the discharge from the nose or eyes, those that drink from the same drinkers or eat from the same feeders.

There are many different types of Coryza, and a vaccine will only tackle a few. There are at present two vaccines available, the one that is a basic Coryza inert vaccine, Talovac 101C. There may be other variations available from Nobilis. There is also a vaccine from Ondersterpoort called TONGAAT CORYZA vaccine, an oil based vaccine specifically targeting a nasty type of Coryza seen since 2006 in SA. If you intend to vaccinate against Coryza you need to do both,  seven days apart.

Once you have diagnosed that you have Coryza and not something else you need to:

Separate the sick birds from the healthy ones.

Take all feeders and drinkers away and remove water and feed. Clean drinkers, dispose of any feed. Give fresh water in a disinfected drinker, (VIRUKILL), and fresh feed in a different disinfected feeder. Dose the sick birds with FosbacT, one teaspoon per litre drinking water, for five days.

When birds have recovered you must use an electrolyte vitamin additive in your drinking water for at least five days to replace vitamins and minerals in the sick birds.

MENTOFIN is a herbal concoction which can be used in the drinking water, or that you can use to steam the birds. It helps them to breathe and clears the sinus. It is not an antibiotic so is a good alternative to use. You can use it  at the same time as the antibiotic FosbacT  in the drinking water.

Steam a kettle on a gas burner  in a closed room and add a teaspoon of MENTOFIN to the water. Close the room door and leave to steam a few minutes. Do this several times a day. It clears the air sacs very well, and relieves the snotty discomfort of the birds.

Birds have a very low pain threshold. They cannot in other words stand much pain or discomfort. You may find that they will die of a Coryza infection, not from the disease itself but because they cannot breathe owing to the mucus build up in their chests. This is why good nursing and steaming the birds, monitoring them closely will go a long way to curing them, more so than the antibiotic you are giving them.

Dose the healthy birds with the same medication, as they are probably compromised as well. Make sure you dose for three days, both flocks.

When the birds have recovered wait at least a week before you reintroduce them to their healthy siblings. Birds that have recovered remain carriers for a while. You can continue with a dose of MENTOFIN, half a ml per litre drinking water for a few days to make sure all the snot has gone. Mentofin does not depleat the system of the birds of vitamin or minerals.

When you handle sick birds, use gloves and dispose of these by burning. Remove shavings in your pen and replace with clean shavings. Burn the old shavings. Make sure you disinfect all water dispensers, water fonts, feeders. Discard any feed you may have used for the sick birds by burning. Do not throw it into the main feeding pen!

MYCOPLASMA GALLISEPTICUM

This is often mis diagnosed as it is often mixed in with other respiratory complaints and eventually you do not know what you are treating. MG is a low key bacterial disease that lurks in any poultry yard no matter how clean. It is often associated with the fungi and spores found in feeds, called aflatoxins,  especially feeds not stored in airtight containers or in climates that are very humid. Old feed left in feeders, and topped up every day is another source of the disease. MG tends to remain active in the system of birds, without symptoms for many months and even is transmitted from flock to flock so you may have the problem for years without being aware of it.

You will only pick up MG if you ask for a random blood test, or if your birds become stressed by heat, cold, vaccination, moving and transport, predators, parasites, lack of food or water.  You may also wonder why your flocks are not growing at the same pace, with some birds not thriving at all and always lagging behind. In times of stress from weather or predators, or stress from secondary infections like Coryza,  the disease which has actually been there all along will surface. The birds will display symptoms like:

Coughing, sneezing, eyes closed, discharge from eyes and mouth. Young birds will be listless, and your flock will not grow at even pace. Some will be bigger than others and the tell tale symptom is birds growing VERY long primary wing feathers while the rest of the body remains undersized and light in weight. Your flock will not gain weight. You will have unexplained deaths. This disease is transmitted vertically, from hen to egg to chick, so you need to be aware of it and vaccinate.

That is MG. The coughing and sneezing will probably be  a secondary Coryza infection jump started by the underlying MG problem.

Birds can test positive via blood tests for MG and be symptom free. You still need to vaccinate!

Vaccinate with AVIPRO 104 MG bacterin. This is an inert oil based vaccine. Vaccinate with half a ml per bird subcutaneously at eight weeks and again at 15 weeks. I say 8 weeks because before that you will be dosing for pox, IB/ND and Gumboro and all that needs to have gone through the system before you use the MG vaccine.

MYCOPLASMOSIS

ALSO KNOWN AS AIR SAC SYNDROME, SINUSITIS, CRD( CHRONIC RESPIRATORY DISEASE) OR EVEN SUMMER SICKNESS.

Mycoplasmosis is actually a combination of diseases, mainly MG which is a common denominator to all, and MS Mycoplasma Synoviae. It is also known as infectious synovitis and is common in turkeys as well as chickens.

CRD was first recognised as a chronic respiratory disease that was mild enough to be ignored in 1956. It did reduce egg production, but caused little mortality. And so it was never treated. Later on, a problem known as “air sac disease” affected young flocks and did cause high mortality. Many birds were stunted, feed efficiency was very bad, and many carcasses were considered unfit for slaughter. Of course as soon as the bottom line was compromised, people began to take notice and scientists started to investigate. They found that CRD, air sac syndrome and sinusitis were all traced back to…MG.

It was discovered that air sac syndrome was the only complaint that combined E coli with MG, a nasty combination, but MG was always present!

MS affects the joints and you may see swollen and inflamed hocks on the birds. Birds are lame and it is painful for them to walk or move.

It was also discovered that not only did MG feature prominently in all these scenarios, but that the weakened immune system of the birds allowed other infections and viruses to compromise the birds: Newcastle, Infectious Bronchitis being the main two.

To their horror, scientists also discovered that birds that had MG in low concentrations were not affected by it, but were carriers, and that the disease was transmitted via the egg to the next generation.

The true CRD produces slight respiratory symptoms, coughing, sneezing, nasal discharge. Air sac syndrome involves the air sacs as well, birds cannot breathe, gasp and seem to drown in snot.

A bird does not have very efficient lungs, but a series of air sacs that are prone to infection, and quickly become over burdened with mucus.

To recap, if you treat MG you will probably dodge the rest of this family of horrors.

Good nursing and close monitoring of your flock, handling problems before they become insurmountable, all helps towards a healthy flock.

ILT (INFECTIOUS LARYNGOTRACHEITIS)

This is more rare in South Africa but it does occur.

It is a viral infection that is derived from a Herpes type virus. It infects the larynx region of the throat, the nasal passages and the upper respiratory tract.

Symptoms are very distinctive:

Frequent sneezing and shaking of the head, producing BLOODY discharge from nose and mouth.

Distinctive cough that sounds more like a child with whooping cough. These are called “callers” because of the distinctive wheezing in the throat.

Birds cannot breathe and often die mouth open, gasping. In serious infections you will find blood on the walls of the poultry cages, where birds have shaken their heads and blood and mucus has flown everywhere. Highly contagious!

On post mortem lesions are found inside the trachea.

Birds are infected by being in contact with infected dead birds, or the discharge from the eyes and nasal passages of their siblings. Water troughs and feeders are also a source of infection much as in Coryza. Unlike Coryza, vaccinating the birds actually makes them carriers for life of this virus and in some states of the US it is illegal to vaccinate against ILT.

This virus does not die a natural death. It remains in your flock for generations unless you actually cull all carriers and start again.

There is a vaccine available now called MLT (Modified Laryngotracheitis) which does give immunity without making the birds perpetual carriers.

The vaccine has been modified to target only the barest form of the disease. Needless to say in a case of serious field challenge it will not be effective.

I would suggest that unless you have PROVED via post mortem that you have ILT in your flock, do not touch the vaccine.

 

124-2447_IMG_2 Plymouth rock White cockerel. Note the clear eyes, no discharge, the red comb, the white feathers unsoiled by mucus.

NEWCASLE DISEASE

This is a virulent viral disease that is endemic in Africa. This means you need to vaccinate because it is present wherever you are.

Unfortunately with Newcastle, by the time you realise you have the disease it is probably too late to do anything about it. death is sometimes the first clue you have that Newcastle is the problem.

There are several types of Newcastle and you will not know what is going on unless you do a post mortem examination. Some types of Newcastle affect the nervous system and birds will end up with the neck twisted around facing backwards, or the head between the legs, and they die in that position. It can affect turkeys as well, and rarely, waterfowl.

The most severe strain of Newcastle is  visceroptic velogenic Newcastle Disease (VVND) and is a serious threat to broiler industries in the US, where strict border control is practised. It is sometimes known as Exotic Newcastle Disease.

The milder form is known as mesogenic Newcastle Disease. This is transmitted via airborne route, but does not travel long distances and will run itself out in 30 days. Birds that recover are not carriers nor are they carriers if they are vaccinated.

Respiratory distress is often accompanied by nervous tremors and paralysis. Egg production drops. Eggs that are laid are mishappen and soft shelled.

There is as with all viruses, no cure and the disease can only be treated by treating secondary infections and symptoms that may arise. Vaccination is cheap and effective. (See section on vaccination).

The spread of this disease is rampant and you can lose a thousand birds a day in a broiler operation.

Some types of Newcastle are not as vicious and you will get coughing, sneezing, rales, snicking, discharge from nose and mouth, closed eyes and weepy eyes. Birds may survive. You might say the symptoms are identical to those of Coryza or even Infectious Bronchitis. Yes, they are, and only a careful examination of the birds will tell you different. The main difference between Newcastle and other infections is the rapid spread of the disease. You may have a healthy flock of a thousand at six am in the morning and be down to two hundred by nightfall of the same day, it is that quick. Nothing else moves that quickly. Only a post mortem will certify Newcaslte.

Fortunately, there are some very good vaccines available to be used as live vaccines via the water from as early as day one. Usually a mild form of ND called Hitchner B1 is given first, and then followed seven days later by the La Sota strain of ND also in water. The first vaccine sensitizes the system to the vaccine, the second provides good immunity. YOU NEED BOTH. (See section on vaccines)

If you suspect that you may have Newcasle in your yard, you need to consult a vet, and declare the epidemic. You also need to ask for a necropsy, post mortem, to certify that it is indeed Newcastle, because many a time there have been scares about this and it has turned out to be Coryza, or avian flu.

INFECTIOUS BRONCHITIS

This is a more slow acting virus that seems to linger in the flock. You will see respiratory distress, a lot of sneezing and weakness of the affected birds.  There may be slight watery nasal discharge. IB is caused by a virus that affects only chickens, birds may survive and do not become carriers if vaccinated. The infection is confined to the respiratory tract and does not affect the nervous system. Duration is ten to fourteen days. Birds in lay will lay soft shelled or shell less eggs. In chicks of six to eight weeks, mortality may be as high as 40%. Growth is retarded, feed consumption is virtually nil. Four weeks is required to get the flock back on track and some birds never recover the full potential of their breed but remain stunted.

There are several strains of this virus, and when it occurs all susceptible birds on the farm will be infected no matter what quarantine precautions you have in place. The virus is spread by air and can “jump” considerable distances. It can be spread via equipment, clothing, mechanical devices like crates. It is not egg transmitted and will only survive one week in a house that has been cleaned and emptied.

INFECTIOUS BURSAL DISEASE (IBD) OR GUMBORO.

This virus is known as Gumboro because it is reputedly transmitted via the boots of poultry farmers and staff.

It is an acute and rapidly transmitted virus, very contagious found among young chicks especially in overcrowded and unsanitary conditions. There is usually a high morbidity.

The virus causes loss of immunity to other viruses and infections and may compromise the ability of the vaccines to do their job.

On post mortem the bursa is seen to be swollen to twice its size, and colour may be affected from yellow, red or even black. It will be slimy to the touch. In cases where the bird has survived longer, the bursa will shrink to half the normal size.

Young chicks affected typically are cold to the touch, huddle together, feathers will be ruffled, and the birds exhibit tremors. They will huddle with eyes closed and cry continuously. If forced to move they move unsteadily. A sudden rise in temperature is followed by this typical drop in temperature that remains until death, usually within two days. There may be whitish diarrhea. Birds do not eat but drink more.

There is no cure. Vaccinate!

You can avoid problems such as described above by:

  1. Always having a hands on attitude to your birds. Do not let some one else do the work, check the birds every day for soiled vents, coughing, huddled birds, birds not moving or listless, closed eyes, birds not eating, or too quiet.
  2. Check last thing at night. When all the birds are roosting, and it is quiet, that is the time you will hear the odd one coughing or sneezing. You can then isolate the victim and treat it.
  3. Make sure your feeders and drinkers are always clean. Clean water every day is a must as warm water left in the sun, or dirty water contaminated by faeces and dirt is a recipe for disaster. The water must be of a quality you would drink. If you expect the birds to drink it that is only fair!
  4. Make sure all feed is kept in a dry and water proof container so as to avoid rats, moisture or fungal growths and pathogens. This way you may avoid MG as well.
  5. Keep houses well aired, well cleaned every day so as to avoid moist wet bedding which leads to coccidiosis and respiratory problems. make sure bedding is dry and clean.
  6. Never overcrowd your houses, and make sure there are enough feeders and drinkers for all. One feeder for ten birds one drinker for six more or less. Overcrowding stresses the respiratory system of chickens.
  7. Use antibiotics sparingly. Feed well and with the correct balanced feed.

 

 

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