Volg ons op Facebook

Negester KK Website banner 600x163px proef2

Poultry diseases of importance to the small farmer

Written by  Dr. Joan Kleynhans
| in Veearts
| August 7, 2015

Poultry are a cheap source of meat and can be kept by anyone, even in backyards. With good management and the correct environment, chickens can be kept healthy and productive. Healthy chickens will produce more meat and eggs.

Disease can spread rapidly amongst chickens because they are housed together and share food and water bowls. It is important to ensure that they have good quality food and clean water. Facilities should be kept clean and free from rats and flies. Water bowls must not leak. Chickens should not be overcrowded and chickens of different ages should be raised separately. Uninvolved people and animals should not enter the chicken houses.

The environment should be controlled to prevent excess heat or cold. Bedding should be kept dry, but not dusty. Do not allow high build-up of chicken droppings. There should be adequate ventilation. Avoid sharp wires in the cages.

“When purchasing chickens, avoid weak, second-grade chickens.”

When purchasing chickens, avoid weak, second-grade chickens. Young chickens are also more susceptible to disease. Ensure that chickens purchased are healthy. Poor condition as a result of underfeeding should be avoided. Chickens should be vaccinated against the most important diseases.

When disease occurs, consult a veterinarian or animal health technician immediately to help identify the disease and best course of action. They may do a post mortem on some of the sick chickens and take samples to send to a laboratory. Ask them to go through your management system with you to identify trouble spots.

Treatment will depend on the cause of disease. In some cases, no treatment will be available, therefore prevention is so important. Separate all sick chickens from the healthy ones daily. Handle and treat the sick chickens last to help prevent the spread of disease.

The following disease symptoms should be watched out for:

Diarrhoea:

The droppings are very loose and watery and of a different colour. Blood may be visible. The loose stool often leads to caking of the feathers around the vent. Chickens appear listless, inactive and reluctant to eat or drink. Growth will be slow and some may die.

Dead chickens show poor condition. Intestines have watery content and are red and swollen. A yellow butter-like substance may be seen around the heart, liver and intestine.

Diarrhoea may be caused by the following:
Bacteria - Salmonella, E. coli, Pasteurella ; Viruses - Newcastle disease, gumboro disease ; Parasites - Coccidioisis, worms ; Fungi - Candida, Aspergillus.

If the diarrhoea is caused by bacteria an antibiotic may be added to the water. Coccidiostats are available to treat coccidiosis. Stress preparations that contain electrolytes, vitamins and minerals may be added to the drinking water.

Upper respiratory diseases

The area between the eye and the beak where the sinuses are located, may be swollen. The eyes may be swollen shut. A discharge may be seen at the nostrils and from the eyes. Initially it may be watery, but often becomes cloudy or yellow due to secondary bacterial infection.

Sneezing and/or coughing may occur and occasionally difficult and noisy breathing may be observed. There is loss of appetite, weakness and weight loss. On post mortem a red windpipe and throat, as well as fluid in the windpipe, may be seen.

Causes include: Mycoplasma; Bacteria - E.coli, Pasteurella, Haemophilus ; Viruses - Newcastle disease, influenza, infectious bronchitis, infectious laryngotracheitis ; Parasites - mites and worms ; Fungi - Aspergillus

Treatment: • Antibiotic as prescribed by a veterinarian • Stress preparations

Nervous signs and lameness

Chickens may walk with a limp, or stay down because they are unable to stand up. They may appear disoriented, stare into the sky, or pull their head and neck over their backs. There may be sores on the breast muscles from lying down a lot.

Causes include: Bacteria - Salmonella, Botulism; Viruses - Newcastle disease, Marek’s disease, avian encephalo-myelitis ;  Fungi - Aspergillus.

Treatment: • Antibiotic will only help if the cause is bacterial. A complete hygiene and disinfection program should be drawn up with the help of a veterinarian. If the cause is viral, e.g. Newcastle disease, spread should be prevented.

Drop in egg production or quality

Possible causes: Bacteria - E.coli, Salmonella;
Mycoplasma; Viruses - Newcastle disease, influenza, infectious bronchitis, infectious laryngotracheitis, avian encephalomyelitis, egg drop syndrome ; Parasites.

Treatment

Antibiotics only if cause is bacterial.
Vitamins and minerals added to drinking water may help.

Newcastle disease

Newcastle disease is a viral disease which  is important worldwide. It causes many deaths and huge losses to chicken farmers. There is no treatment and the disease spreads rapidly in an outbreak. Sick chickens should be slaughtered and burned immediately.

Affected chickens show nervous signs such as twisted necks (torticollis), paralysis, depression, sneezing, swollen eyes, difficult breathing and diarrhoea. They die within 3 to 5 days. Newcastle disease is a controlled disease and a state vet must be notified.

Prevention: Healthy chickens should be vaccinated before they contract the disease. Once signs appear in the flock, it is already too late.

Newcastle spreads to other properties easily. In an outbreak, avoid visiting other premises where chickens are kept. Wear clean clothes and shoes when you do leave your property. Advise your neighbours to vaccinate their chickens. Clean the chicken houses with soap and water. Disinfect all equipment and also clothing used. Burn all chicken litter and dead chickens.

Generally speaking, many chicken diseases cannot be successfully treated. It is therefore important to prevent disease through good management and vaccination where possible.

References:
http://www.nda.agric.za/docs/poultry/poultrydisease.htm
http://www.mediafire.com/view/rpx903k361f9q9g/Important_Poultry_Diseases_060058_-_CPC_website.pdf