Like every other livestock farming, poultry diseases are numerous, each with its signs and symptoms. Here are some common poultry diseases along with their typical signs and symptoms:

Newcastle Disease

Newcastle Disease is a highly contagious poultry disease (viral infection) that affects various bird species, including poultry.

Causative Agent

The causative agent of Newcastle Disease is the Newcastle Disease Virus (NDV), belonging to the family Paramyxoviridae, genus Avulavirus.

Transmission

The virus spreads through contact with infected birds, contaminated equipment, feces, and respiratory secretions. Wild birds can also carry and transmit the virus. Human handling and movement of infected birds can facilitate its spread.

Prevention and Control

Vaccination: Vaccination is the primary method of prevention. Live and inactivated vaccines are available and are administered according to the vaccination schedule recommended by veterinarians.

Biosecurity measures are crucial to prevent the introduction and spread of the virus. These include limiting access to the farm, disinfecting equipment and footwear, and preventing contact with wild birds.

Routine administration of recommended antibiotics and multivitamins to boost immunity is recommended.

Quarantine and culling infected and exposed birds may be necessary to control outbreaks.

Surveillance programs help monitor the prevalence of the disease and detect outbreaks early.

Economic Impact

Newcastle Disease can have significant economic consequences due to mortality, decreased egg production, treatment costs, and trade restrictions imposed in affected areas.

Zoonotic Potential

While Newcastle Disease primarily affects birds, rare cases of human infection have been reported, usually associated with direct exposure to infected birds or their tissues. However, human infections are generally mild and self-limiting.

Signs and symptoms

Respiratory symptoms include gasping, coughing, and sneezing.

• Watery diarrhea.
• Depression and nervous signs such as twisting of the neck.
• Drop in egg production.
• High mortality rates, especially in chicks.

Avian Influenza (Bird Flu)

Avian influenza, known as bird flu, is a poultry disease (viral infection) primarily affecting domestic poultry and wild birds. Here’s an overview of avian influenza:

Causative Agent

Avian influenza viruses belong to the family Orthomyxoviridae, genus Influenzavirus A. They are RNA viruses with various subtypes classified based on their surface proteins: hemagglutinin (H) and neuraminidase (N). The most significant subtypes regarding poultry health and potential human transmission are H5, H7, and H9.

Transmission

Avian influenza viruses spread through contact with infected birds, their saliva, nasal secretions, feces, and contaminated environments. Wild birds, particularly waterfowl, serve as natural reservoirs of the virus and can carry it over long distances during migration. Human activities, such as poultry farming and trade, can facilitate the spread of the virus between domestic bird populations.

Signs and symptoms

• Sudden onset of severe illness.
• Respiratory signs include coughing, sneezing, and difficulty breathing.
• Swelling of the head, eyelids, comb, and wattles.
• Nasal discharge.
• Drop in egg production.
• High mortality rates.
• Infectious Bronchitis
• Respiratory symptoms include coughing, sneezing, and nasal discharge.
• Drop in egg production and poor egg quality (soft-shelled eggs, misshapen eggs).
• Kidney damage leads to increased water consumption and wet droppings.
• Depression and reduced feed intake.

Prevention and Control

Biosecurity measures are essential to prevent the introduction and spread of avian influenza. These include controlling access to poultry facilities, disinfecting equipment, and implementing measures to minimize contact with wild birds.

Vaccination may be used in some regions to control the spread of specific avian influenza strains. However, organic farmers are advised to follow their organic schedules holistically to avoid outbreaks.

Surveillance programs are conducted to monitor the prevalence of avian influenza in poultry populations and wild bird populations.

Early detection and reporting of suspected cases are critical for rapid response and containment of outbreaks.

In areas where outbreaks occur, measures such as quarantine, culling of infected and exposed birds, and disinfection of premises are implemented to control the spread of the virus.

Coccidiosis

Coccidiosis is a common and economically significant poultry disease caused by protozoa of the genus Eimeria. These parasites infect the intestinal tract of birds, leading to symptoms such as diarrhea, weight loss, decreased feed intake, and, in severe cases, mortality. Coccidiosis can result in significant economic losses due to reduced growth rates, decreased egg production, and the cost of treatment and prevention.

Signs and Symptoms

• Bloody diarrhea.
• Droopiness and reluctance to move.
• We have reduced feed intake and weight loss.
• Ruffled feathers and huddling.
• Pale comb and wattles.
• Prevention and Control
• Good management practices and biosecurity measures are crucial for preventing the introduction and spread of coccidiosis on poultry farms.
• Cleanliness and proper sanitation of housing facilities, feeders, drinkers, and litter are essential to minimize the buildup of oocysts in the environment.

Anticoccidial drugs, either through medicated feed or water, are common for preventing and controlling coccidiosis in poultry. However, overuse or misuse of anticoccidials can lead to drug resistance.

Vaccination with live or attenuated vaccines is another strategy to control coccidiosis, particularly in commercial poultry production systems.

Careful and holistic administration of organic medications following a working organic schedule provides close to 95 percent effectiveness

Fowl Cholera

Fowl cholera, also known as avian cholera or avian pasteurellosis, is a highly contagious poultry disease cause by a bacterial that affects birds, particularly domestic poultry and wild waterfowl. It is caused by the bacterium Pasteurella multocida. Fowl cholera can devastate poultry flocks, leading to high mortality rates if not properly managed.

Mode of Transmission

The disease spreads through contact with infected birds or contaminated environments such as water, feed, or soil. Symptoms of fowl cholera can vary depending on the strain of the bacteria and the bird species affected. Still, common signs include lethargy, decreased appetite, respiratory distress, diarrhea, swollen wattles or joints, and sudden death.

Signs and Symptoms

• Sudden death in apparently healthy birds.
• Swelling of the wattles and comb, which may turn blue.
• Loss of appetite and decreased egg production.
• Greenish diarrhea.
• Respiratory symptoms like coughing and difficulty breathing.

Prevention and Control

Prevention of fowl cholera involves strict biosecurity measures to prevent the introduction of the bacteria into poultry flocks, such as controlling access to wild birds and regularly disinfecting facilities. Vaccination may also be used to help protect against the disease.

Treatment typically involves antibiotic therapy to control the bacterial infection, but prevention and management are key due to the disease’s rapid spread and potential severity. Proper sanitation, hygiene, and monitoring are essential for controlling fowl cholera outbreaks in poultry populations.

Marek’s Disease

Marek’s disease is a viral infection primarily affecting poultry, especially chickens. It’s caused by a herpesvirus called Gallid herpesvirus 2 (GaHV-2). Marek’s disease is highly contagious and can spread rapidly within flocks through airborne transmission or by direct contact with contaminated feces, dander, or feathers.

This poultry disease primarily targets the immune system, nervous system, and sometimes the organs such as the liver, spleen, and kidneys.

Signs and Symptoms

Symptoms can vary widely and may include paralysis, weight loss, diarrhea, and tumors in various organs. Marek’s disease can have a significant economic impact on the poultry industry due to mortality, decreased egg production, and the cost of control measures. Other signs and symptoms include:

• Paralysis of one or both legs, wings, or neck.
• Tumors on internal organs, skin, and muscles.
• Weight loss and poor growth.
• Behavioral changes like depression and aggression.
• Eye changes such as irregular pupil shape.
• Infectious Bursal Disease (Gumboro):
• Diarrhea, often watery and foul-smelling.
• It decreased feed intake and weight loss.
• Immunosuppression leads to increased susceptibility to other diseases.
• Drop in egg production.
• Increased mortality, especially in young birds.

Prevention and Control

Prevention of Marek’s disease often involves vaccination, as there is no cure once the bird is infected. Vaccination typically occurs shortly after hatch and is crucial to disease control in commercial poultry operations. Additionally, strict biosecurity measures are essential to prevent the introduction and spread of the virus within poultry flocks.

Fowl Pox

Fowl pox is a viral poultry disease that affects birds, particularly chickens and turkeys. It is caused by the avian poxvirus, which is a member of the Poxviridae family. The disease primarily manifests in cutaneous (skin) pox and diphtheritic (wet) pox.

Types or Forms Of Pox Infection

Cutaneous (Skin) Pox: This form of fowl pox appears as wart-like lesions on the unfeathered parts of the bird’s body, such as the comb, wattles, legs, and sometimes around the eyes. The lesions can vary in size and severity, ranging from small, raised bumps to larger, cauliflower-like growths. Infected birds may experience discomfort and itching.

Diphtheritic (Wet) Pox: This form of fowl pox affects the mucous membranes of the mouth, throat, and upper respiratory tract. It can lead to the formation of grayish-white plaques or membranes in these areas, which can cause difficulty in breathing, eating, and drinking. This form is generally more severe and fatal, especially in young birds.

Mode of Transmission

Fowl pox is transmitted through direct contact with infected birds or contaminated surfaces. Mosquitoes can also act as vectors, transmitting the virus from infected birds to healthy ones. Prevention measures include vaccination, mosquito control, and good biosecurity practices.

Signs and Symptoms

• Lesions on the skin and mucous membranes, typically starting as raised white nodules and progressing to scabs.
• Reduced feed intake and weight loss.
• Respiratory symptoms if the lesions are present in the respiratory tract.
• It decreased egg production.

Treatment

Treatment for fowl pox is primarily supportive, focusing on alleviating symptoms and preventing secondary infections. Infected birds should be isolated from the rest of the flock to prevent the spread of the disease. Vaccination effectively prevents fowl pox outbreaks in poultry flocks, with both live and inactivated vaccines available.

Coryza

Coryza, also known as infectious coryza, is a common respiratory poultry disease particularly chickens. The bacterium Avibacterium paragallinarum causes it. Coryza primarily affects the upper respiratory tract of chickens, causing symptoms such as nasal discharge, swelling of the face and wattles, conjunctivitis, and sometimes difficulty breathing. Infected birds may also exhibit decreased egg production and poor growth.

Mode of Transmission

Transmission of coryza typically occurs through direct contact with infected birds, contaminated equipment, or aerosolized droplets from infected birds’ respiratory secretions. The disease can spread rapidly within a flock, especially under conditions of crowding and stress.

Signs and Symptoms

The signs and symptoms of coryza in poultry can vary in severity but typically include:

Nasal discharge: Birds affected by coryza often exhibit nasal discharge, ranging from clear to mucoid or purulent (containing pus).

Swollen face and wattles: Coryza can cause swelling of the face, particularly around the eyes, sinuses, and wattles (the fleshy lobes hanging from the chin).

Conjunctivitis: Inflammation of the conjunctiva, the membrane lining the inner surface of the eyelids and covering the eyeball, may occur. This can lead to red, swollen, and sometimes cloudy eyes.

Difficulty breathing: Some birds may experience respiratory distress, manifested by open-mouthed breathing, wheezing, or gasping for air, especially in severe cases.

Decreased egg production: Infected laying hens may decrease or produce eggs with abnormal shells or quality.

Poor growth: In young birds, coryza can result in poor growth rates and reduced feed conversion efficiency.

Depression and decreased activity: Affected birds may appear passive, with reduced activity levels and reluctance to move around.

Foul odor: In advanced cases, a foul odor may be noticeable, especially around the bird’s head, due to purulent nasal discharge.

Prevention and Control

Preventing coryza involves good biosecurity practices, such as quarantining new birds before introducing them to the flock, maintaining a clean environment, and controlling pests that can carry the bacteria. Vaccination is also an effective measure to prevent the disease, with several commercially available vaccines targeting Avibacterium paragallinarum.

Early detection and prompt treatment are essential to control the spread of coryza within a flock. Treatment typically involves the administration of antibiotics, although antibiotic resistance can be a concern in some cases. Poultry producers must work closely with veterinarians to develop effective prevention and control strategies tailored to their specific circumstances.

It’s important to note that the severity of symptoms can vary depending on factors such as the strain of the causative bacteria, the age and health status of the birds, environmental conditions, and the presence of concurrent infections or stressors. Prompt diagnosis and treatment are crucial to minimize the impact of coryza on poultry health and production.

Chronic Respiratory Disease (CRD)

Chronic Respiratory Disease (CRD) is a common respiratory illness in poultry, particularly chickens, caused by several infectious agents, with Mycoplasma gallisepticum being the primary culprit.

Causative Agent

CRD is primarily caused by Mycoplasma gallisepticum (MG). Still, other pathogens such as Mycoplasma synoviae (MS), Infectious Bronchitis Virus (IBV), Avian Reovirus (ARV), and others can also contribute to the disease.

Mode of Transmission

CRD typically spreads through direct contact with infected birds, contaminated equipment, or aerosolized droplets from infected birds’ respiratory secretions. Vertical transmission (from infected hens to their offspring) can also occur.

Signs and Symptoms

• Coughing
• Sneezing
• nasal discharge
• swollen sinuses
• conjunctivitis (inflammation of the eye membranes),
• difficulty breathing,
• reduced feed consumption
• decreased egg production
• poor growth rates in young birds.

Economic Impact

CRD can have significant economic consequences for poultry producers due to decreased production efficiency, increased mortality, and the cost of implementing disease control measures.

Prevention and Control

Preventing and controlling CRD involves:

• Implementing strict biosecurity measures, such as quarantining new birds.
• Controlling wild birds and pests.
• Disinfecting equipment.
• Maintaining good ventilation in poultry houses.

Vaccination against Mycoplasma gallisepticum and other relevant pathogens can also be important to disease control strategies.

Treatment

Chronic respiratory infections can lead to long-term damage and may predispose birds to secondary infections.

Antibiotics are commonly used to control bacterial infections associated with CRD. However, Mycoplasma infections can be challenging to treat due to the bacteria’s unique characteristics, such as lack of a cell wall. Treatment may help alleviate symptoms and reduce secondary bacterial infections but may not completely eliminate the underlying infection.

Overall, effective management practices, including biosecurity, vaccination, and proper treatment protocols, are essential for preventing and controlling Chronic Respiratory Disease in poultry flocks. Regular monitoring and surveillance for respiratory diseases are also important for early detection and intervention.

These are just a few examples of the many diseases that can affect poultry. Proper biosecurity measures, vaccination, and prompt veterinary care are crucial in preventing and managing these diseases.