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The half-life of maternal antibody (mAb) titres against Newcastle Disease Virus (NDV) were estimated in order to trace its likely declining pattern and the influence on the efficacy of vaccination in broiler chicks. Our study was also conducted to compare two vaccination regimens with live and inactivated NDV vaccine. For this purpose, ninety day-old broiler chicks with known NDV vaccination history of parent stock were randomly allocated into three groups (I) unvaccinated control, (II) Live NDV vaccine, and (III) Live + Inactivated NDV vaccine. Haemagglutination-inhibition (HI) antibodies were determined in the pre- and post-vaccination sera of the experimental chicks. The results indicated that the unvaccinated group showed higher level of mAb against NDV at day 1 with HI antibody titre (Log2) 9.32 which was maintained up to 7 days of age (8.11) and gradually declined with no measurable antibodies of maternal origin after day 14, signifying the initiation of Newcastle Disease (ND) vaccination at 7 days of age. The vaccinated Group II and III revealed significantly higher HI titre at day 14 (11.52, 12.42), day 21 (12.95, 13.22), day 28 (11.63, 12.18) and day 35 (13.31, 13.39) than the unvaccinated control group I. Moreover, there is no significant difference in humoral immune response among both the vaccinated groups. Thus, our study suggests the use of live NDV vaccines for ND prevention in commercial broiler farming over the inactivated NDV vaccines which demands a withdrawal period before slaughter and its economic implication due to additional cost. This study also indicated that the half-life values of mAb and its effect should be considered while customizing an effective vaccine regimen.

A study was conducted to see the incidence of avian pox in different districts of Asom and one district of Nagaland, where outbreaks, 29 of fowlpox, 13 of pigeonpox and 3 of duckpox were recorded. The age wise morbidity and cause specific mortality in case of fowlpox was recorded at 0–8 weeks (19.63 and 23.60%), at 9–20 weeks (5.57 and 14.43%) and above 20 weeks (1.39 and 11.11%), respectively. Likewise, in pigeonpox, morbidity and cause specific mortality were recorded at 0–8 weeks (11.11, 0%), 9–20 weeks (30.68, 37.03%) and above 20 weeks (35.08, 30%), respectively. Again in case of duckpox, morbidity was recorded at 0–8 weeks (10%), 9–20 weeks (0%) and above 20 weeks (6.66%), while no mortality was recorded among the ducks. External examination revealed erosions, crusts and several small, multifocal to coalescing wart-like nodules on various parts of the affected birds. During post-mortem examination, few birds showed fibronecrotic lesions on mucous membrane of the oral cavity and upper respiratory tract. Histopathological examination of the scab samples revealed intracytoplasmic eosinophilic inclusion bodies. During ultrastructural study, inclusion bodies were seen in the cytoplasm of the skin epithelium,which consist of numerous, dumbbell-shaped bodies typical of pox virions. During molecular diagnosis, out of 29fowlpox, 9 pigeonpox and 3 duckpox suspected samples 86.20, 77.77 and 100% samples, respectively, were foundpositive by polymerase chain reaction.

Abstract:The experiment was carried out to study the effects of different doses of pig dung on the growth rate of Catlacatla during the summer season. Rate of application of pig dung doses were 10000 kgha -1 yr -1

Newcastle disease (ND) is a highly contagious viral disease of poultry causing significant economic losses worldwide. Vaccination is considered the most reliable approach to curb the economic menace that is ND, but the thermolabile nature of Newcastle disease virus (NDV) vaccination poses a significant threat to its protective efficacy. This study aimed to profile the thermostability of NDV isolates from duck (As/Km/19/44) and parrot (As/WB/19/91) and evaluate their immunogenic potential in chicks. Fusion protein cleavage site (FPCS) and phylogenetic analysis demonstrated the lentogenic nature of both the isolates/strains and classified them as class II genotype II NDV. The characterized NDV isolates were adapted in specific-pathogen-free (SPF) chicks by serially passaging. Biological pathogenicity assessment of chicken-adapted As/Km/19/44 (PSD44C) and As/WB/19/91 (PSP91C) revealed both the isolates to be avirulent with a mean death time (MDT) of more than 90 h and an intracerebral pathogenicity index (ICPI) ranging from 0.2 to 0.4. Both of the NDV isolates displayed varied thermostability profiles. PSD44C was the most thermostable strain as compared to PSP91C and the commercially available LaSota vaccine strain. The immunogenicity of PSD44C and LaSota was significantly higher than PSP91C. Based on these results, it is concluded that NDV isolate PSD44C is more thermostable and immunogenic when administered intraocularly without any adverse effects. Therefore, PSD44C is suitable for further research and vaccine development.

The Indian poultry market is estimated to have an annual growth rate of 8.1% as of today. However, infectious diseases in poultry pose an important constraint in the growth and development of this sector in our region. Among infectious diseases, viral diseases of poultry pose a serious threat to the poultry industry from an economic point of view. Several viral disease outbreaks have been reported by various researchers from different parts of the country. Among the common viral diseases of poultry, incidences of Newcastle disease, Avian Influenza, Fowl Pox, Infectious Bursal Disease, Marek’s disease, Infectious Bronchitis, Infectious Laryngotracheitis and Inclusion Body Hepatitis are significant in Assam as well as other parts of India. Thorough epidemiological studies followed by the identification of different serotypes, pathotypes, strains, etc. by genotyping and molecular characterization of viral disease pathogens may lead to ways to control and eradicate the diseases. Importance should be given to maintaining basic preventive measures like biosecurity, farm hygiene, and proper vaccination. In a developing country like India, disease outbreaks can impact the country’s economy. In this study, a brief view of the common viral disease of poultry and its diagnosis and control strategies in Assam, India is depicted. However, this review well indicates a plethora of avian diseases that have occurred over the years causing a severe impact on poultry farming as a whole.

The present study was carried out to detect the circulating Newcastle disease virus (NDV) from various field outbreaks in Assam during 2018-2021. Nine hundred ninety-two clinical and post mortem samples were collected from the backyard and commercial poultry and subjected to molecular detection by Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). NDV could be detected in 445 (n=757, 58.78%) tissue samples and 53 (n=235, 22.55%) cloacal swabs collected from suspected poultry cases by RT-PCR. The findings of our study suggests that the sample of choice for detection of NDV from tissue samples was trachea (n=85, 92.94%), followed by spleen (n=96, 90.62%), lung (n=92, 86.95%), caecal tonsils (n=96, 77.08%), proventriculus (n=74, 60.81%), brain (n=92, 48.91%), intestines (n=73, 31.50%), kidney (n=52, 23.07%), and cloacal swab (n=235, 22.55%) by RT-PCR. Hence, the collection of specific tissue samples from field outbreaks for the detection of NDV is of paramount importance. In addition, RT-PCR can be considered a highly sensitive detection method for rapid and confirmative diagnosis of Newcastle disease virus.