Abstract
<i>Clostridium perfringens</i> organisms have an economic concern in poultry production. The purpose of this study was to investigate <i>Net B</i> and β<sub>2</sub> <i>C. perfringens</i> positive isolates in broiler farms and their clinic-pathological effects in broiler chicks. A bacteriological examination of <i>C. perfringens</i> was carried upon 92 Necrotic enteritis (NE) diseased cases and 55 apparently healthy broilers of different ages in Egypt. <i>C. perfringens</i> type A was only recovered (49.7%). <i>cpa</i> gene was detected in 100% of samples with PCR technique. NE diseased cases exhibited both <i>Net B</i> (87.5%) and <i>cpb<sub>2</sub></i> (75%) toxin genes. Experimentally, an intra-gut induction of <i>Net B</i> and β<sub>2</sub> <i>C. perfringens</i> toxins were evaluated in chicken models. The hematological studies revealed hemolytic anemia 5 days post infection (p.i) in <i>Net B</i> and β<sub>2</sub> inoculated groups (G1&G2). Leucogram revealed neutrophilia and lymphopenia 5 days p.i. A significant increase in ALT, AST, uric acid and creatinine serum levels were recorded in the infected groups at 5<sup>th</sup> and 12<sup>th</sup> day p.i. DNA Sequencing for <i>net B</i> gene revealed an amino acid replacement from glutamate into arginine at codon 379 with silent mutation was also detected at nucleotide 1134. Sequencing of both toxin genes were recorded in the gene bank for the first time in Egypt. This study pointed out that <i>C. perfringens Net B</i> toxin, is a new key virulent factor for the development of NE. Further studies of <i>Net B</i> toxiod for vaccine production could minimize the clostridial problems in broiler farms.
Highlights
Necrotic Enteritis (NE) is one of the most important diseases in poultry which destroys the intestinal lining cells of the digestive tract occurring outbreaks in broilers from 25 weeks of age
C. perfringens was isolated in both NE diseased and healthy broiler 49.7% (73/147)
The highest incidence rate of C. perfringens was recorded in 2-3 weeks of age (52.8%) as shown in (Table 3)
Summary
Necrotic Enteritis (NE) is one of the most important diseases in poultry which destroys the intestinal lining cells of the digestive tract occurring outbreaks in broilers from 25 weeks of age. It is caused by C. perfringens, which is an important pathogen of a wide spectrum of veterinary diseases [1]. In acute form, NE causes sudden death of many birds within a few hours, without showing any clinical signs of the disease [2], Sub-clinical form may be the most important manifestation of enteritis as it is likely to go undetected and untreated [3]. In the global poultry industry, NE is considered an emerging billion-dollar disease [4, 5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
