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Pigeon paramyxovirus type 1 (PPMV-1) is a serious pathogen facing the pigeon industry. Thus, this study aimed to preparation and evaluation of two inactivated vaccines using Carbopol and Aluminum hydroxide-based adjuvants to control such a problem. A total of 45-four weeks old, apparently healthy pigeons were allocated into 3 groups (15 birds each) as follow: group 1 (G1) received 0.5 ml, S/C Carbopol adjuvanted vaccine, group 2 (G2), received 0.5 ml S/C of aluminum hydroxide-based vaccine, group 3 (G3) received 0.5 ml S/C sterile saline and kept as control group. Five serum samples were obtained from each bird weekly post vaccination to measure anti-PPMV-1 antibodies using HI test. At 35 days post immunization, all vaccinated pigeons were challenged with 20µl containing 106 EID50/bird of PPMV-1 YA/14 strain by eye drop route, all pigeons were kept under observation for 10 days during the observation period any clinical signs or moralities were recorded also, cloacal swabs were collected 4-, 7- and 10-days post challenge to measure the shedding level. The potency test revealed that the prepared inactivated vaccine (PPMV-1) with synthetic polymeric adjuvants were potent and efficient. By studying the elicited serum antibody dynamics in vaccinated pigeon using HI test showed that antibody, the beak antibody titer reached by the 4th week post immunization (6 and 5 log 2) for both G1 and G2 respectively (but G1 is significantly increase than G2) and continued to the 5th week where it reaches 6.5 and 5.6 log2 for both groups in order. (G1 is significantly increase than G2), which indicated that the PPMV-1 inactivated vaccine in both G1 and G2, results in systemic adjuvant activity, including a long-lasting protective immune response after a single dose administration without any adverse reaction. G1 and G2 showed the lowest shedding level that was zero at the 10th day post challenge and the overall reduction level of both vaccinated groups was 4.9 and 4.5 for both G1 and G2, respectively. However, the prepared inactivated PPMV-1 Carbopol based vaccine is safe and could significantly poses the immune response more effectively than the aluminum hydroxide-based vaccine. [ABSTRACT FROM AUTHOR]

Vaccines against the virulent Newcastle disease virus (NDV) are broadly existing and can provide protection; nevertheless, better immunization practices are required to avoid clinical disease and limit virus circulation. This study evaluating the immunogenicity and protective efficiency of locally prepared clone 30 live-attenuated vaccine against the challenge impact of virulent NDV genotype IV and genotype VIId prevalent in Egypt in comparison with the commercially prepared live Lasota vaccine as a positive control group. The efficacy of the vaccine was evaluated based on the antibody titer, protection rate, oropharyngeal, and cloacal shedding. Therefore, 150 one day old specific pathogen free chicks (SPF) were divided in to three groups 50 bird per group (G), G1and G2 received 100 µl containing 6 log10 EID50 via the oculo-nasal route of clone 30 vaccine and lasota vaccine in order, while G3 (unvaccinated) received sterile saline at the same route and dose. On day 21 post vaccination (pv) 40 bird from each group were challenged with a dose of 6.5 log10/ml EID50 intramuscular per bird for both genotype IV and genotype VIId (20 bird/genotype virus), the other 10 birds left from each group were kept separate for antibody level monitoring for the 6th week pv. Results revealed that, during vaccine preparation, the clone 30 virus showed a high virus titer when propagated in SPF embryonating chicken eggs (SPF-ECEs), which reached 1012/EID50/ml. The protection rate due to the clone 30 vaccine and the lasota vaccine was alike and showed 75% and 70% against challenge with genotype IV and genotype VIId, respectively, there were no significant differences (p > 0.05) between the antibody titer produced by the clone 30 vaccinated group and lasota group. Both the clone 30 and lasota vaccines showed nearly similar levels of oropharyngeal and cloacal shedding. The results clarify that, although there were no detected differences between the immune response and the protective efficacy of clone 30 vaccine and lasota vaccine but, the use of clone 30 vaccine is still advantageous for its superior immunogenicity and low post-vaccinal reaction, which will make the clone 30 vaccine suggestive for primary immunization, especially in immunologically naive birds. In conclusion, the prepared Clone 30 vaccine in the current study is safe for chicks and can be used as an effective vaccine against the circulating NDV. [ABSTRACT FROM AUTHOR]