Progress and problems in vaccination against necrotic enteritis in broiler chickens

Area of Science:

• Poultry Science
• Veterinary Immunology
• Bacteriology

Background:

• Necrotic enteritis (NE) in broilers is a significant gastrointestinal disease caused by Clostridium perfringens NetB toxin.
• NE prevalence has increased globally due to intensive broiler production practices.
• Current prevention involves managing predisposing factors and feed additives, but vaccination offers a promising alternative.

Purpose of the Study:

• To review historical and current vaccination strategies against NE in broilers.
• To identify key immunogenic proteins and assess their protective efficacy.
• To explore future vaccination approaches suitable for the broiler industry.

Main Methods:

• Review of published literature on NE vaccination in broilers.
• Analysis of studies identifying immunogenic proteins, including NetB toxin.
• Evaluation of different vaccination regimens and delivery systems.

Main Results:

• Crude supernatant vaccines were initially used, but newer strategies focus on specific immunogenic proteins.
• Combinations of antigens are more effective than single proteins for protection against severe NE.
• Existing multi-dose and single-dose regimens for day-old chicks show limited efficacy in field conditions.

Conclusions:

• Future broiler NE vaccination strategies must consider antigen combinations and practical delivery methods.
• Potential field-applicable strategies include breeder hen vaccination, in ovo vaccination, and live attenuated vectors.
• Developing effective, single-administration vaccines is essential for the broiler industry.