Resistance to Velogenic Newcastle Disease Virus in Leghorn Chickens by Use of Prophylactic Lymphokines

Abstract

A group of 1-day-old commercial leghorn chickens was prophylactically treated with lymphokines obtained from lymphocyte cultures of chickens previously infected with Salmonella enteritidis (S. enteritidis-immune lymphokines [SE-ILK]) with the objective to investigate the effect of SE-ILK on development of Newcastle disease (ND) infection caused by Chimalguacan strain, a Mexican velogenic ND virus (vNDV). Clinical signs, histologic lesions, and hemagglutination-inhibition (HI) serum titers were compared with four other groups, namely, chickens without SE-ILK treatment with virus challenge; with SE-ILK without virus challenge; with nonimmune lymphokine (NILK) treatment and virus challenge; with lymphokine treatment and no virus challenge. SE-ILK was administered intraperitoneally in a dose of 0.5 ml/chicken and was followed 30 min later with the challenge of vNDV in a dose of 10(7.6) 50% embryo lethal dose/ml per bird. Birds were observed during 21 days of postchallenge. Detection of histologic changes and virus isolation procedures were carried out on the third, seventh, 14th, and 21st postinoculation days. HI tests were performed first before treatment and later on the days of histologic sample collection except on the third postinoculation day. Results showed that SE-ILK administration conferred resistance to the chickens because: 1) it significantly diminished the severity of ND infection by inhibiting appearance of clinical signs (P < 0.001), lesions (P < 0.005), and histopathologic changes (P < 0.005); 2) it decreased vNDV isolation rate from the organs (P < 0.001), and 3) it potentialized and even accelerated (P < 0.005) primary immune response by antibodies in the presence of vNDV.

Using T cell lymphokines to enhance the immune response against Newcastle disease in vaccinated broiler chickens fed naturally contaminated diet with different mycotoxins

“…The results of the present study showed a significant increase in the Abs against ND in G3 compared with other groups, this return to the role of SILK enhancing the immune response after vaccination with live vaccines through drinking water in the first periods of chick life, also increasing response after oil vaccination these results agree with (15), whom demonstrated the role of SILK in increasing the cytokines which are natural stimulators and mediators of immune cells towards infectious organism thus increasing special Abs against antigens (Ag) and have an effective and influential role in stimulating and differentiation of immune cells in natural and acquired immunity. Rashad and Mushtaq,(10), demonstrated the role of SILK in protection the chicks from ND infection after challenge with virulent local isolate of ND in the first day.…”

Immune response to Newcastle disease virus in chicken lines divergently selected for cutaneous hypersensitivity

“…In current intensive poultry production systems, chickens are exposed to a variety of potentially pathogenic microorganisms. Because of this huge antigenic exposure, vaccinations and/or antibiotic treatments are not always effective (Alfaro et al ., 2002). Genetic selection seems to be a promising alternative approach for improving disease resistance of birds (Gavora & Spencer, 1983; Lamont, 1998).…”