Molecular characterization and pathology of field isolates of foot-and-mouth virus in Swiss albino mice.

Foot-and-mouth disease is responsible for severe economic losses to the livestock industry of Pakistan. This study aimed to use Swiss albino mice as a cost-effective experimental animal model to study different immunological and histopathological aspects of FMDV instead of natural targeted species like cattle. After isolation of field isolates FMDV on BHK-21 cell line, biological titer of the virus and mice infectious dose50 was calculated. Virus was injected in 45 Swiss albino mice (group A) through intraperitoneal route. The gross, histopathological and immunopathological lesions in heart, trachea and lungs were recorded at different day's intervals. Histopathologically, the heart showed congestion, hemorrhages and necrosis of cardiac muscles. Trachea showed deciliated epithelium and lungs showed hemorrhages, bronchial edema and alveolar emphysema. Immunohistochemical studies revealed the presence of virus in cardiac muscles, tracheal and bronchial epithelium and alveolar lumen. The findings evoked a thought that laboratory animals could be an alternative to large animals to meet budget limitations for further research on foot-and-mouth-disease.

Elucidating antiviral activity of Curcuma longa against H9 N2 influenza virus using embryonated chicken egg model.

Curcumin is a potent antimicrobial herb used traditionally as a spice in culinary. This study was designed to evaluate the antiviral effects of curcuma longa extract against H9 influenza virus. A total of 60 embryonated eggs were equally divided into 5 groups with 12 eggs in each group. Group 1 (G1) served as uninfected negative control. Whereas Group 2 (G2) was kept as positive control infected with known virus @ 0.2 ml with 10-9.3 EID50. Group 3 (G3) was offered Curcuma longa @ 0.2 mg/0.2 ml and H9N2 virus (@ 0.2 ml with 10-9.3 EID50. Similarly, Group 4 (G4) was inoculated with extract of Curcuma longa @ 0.2 mg/0.2 ml per egg, whereas Group 5 (G5) was given Ribazole @ 0.2 ml/ egg. The crude extract and virus were administered on the 15th day of incubation and were checked after every 24 hours up to 96th hour post inoculation by random selection of 3 eggs. Death and survival rate were noted in all groups. Gross and histopathological lesions were also observed. Results revealed that Curcuma longa extract had significantly (p<0.05) reduced the mortality rate of embryos infected with H9N2 virus. In G3, increased lymphocytes and mild fatty changes were seen in liver. Whereas, mature RBCs, plasma cells and some lymphoblast's were observed in Spleen. Similarly, the bursa follicles were with lymphocytic aggregation. The G4 (Curcuma longa) and G5 (Ribazole) were with maximum embryo survival after 48 and 72 h post inoculation. This study revealed potential antiviral activity of Curcuma longa against H9N2 influenza viruses and can be opted as alternative to antibiotics and antiviral drugs to minimize the antimicrobial resistance in human and animal population.

Response of lymphatic tissues to natural feed additives, curcumin (Curcuma longa) and black cumin seeds (Nigella sativa), in broilers against Pasteurella multocida.

The antibiotic residues and pathogenic resistance against the drug are very common in poultry because of antibiotics used in their feed. It is necessary to use natural feed additives as effective alternatives instead of a synthetic antibiotic. This study aimed to investigate the immune response of Nigella sativa and Curcuma longa in broilers under biological stress against Pasteurella multocida. The total 100, one-day-old chicks were divided into 5 groups. Groups 1 and 2 served as control negative and control positive. Both control groups were receiving simple diet without any natural feed additives, but the infection was given in group 2 at day 28 with the dose of 5.14 × 107 CFU by IV. Groups 3A and 3B were offered 2% seed powder of Nigella sativa, groups 4A and 4B were offered C. longa 1% in powdered form, and group 5A and 5B were offered both C. longa 1% and N. sativa 2% in the feed from day 1 and groups 3B, 4B, and 5B were challenged with P. multocida. The haemagglutination inhibition titter against Newcastle Disease virus (NDV), feed conversion ratio, mortality, gross, and histopathology were studied. The results of this study revealed that hemagglutination inhibition titers against NDV were highly significant (P < 0.05) in treated groups, highest titers (3A, 6.8; 3B, 6.4; and 5A, 7.2) were obtained from treated Groups. The feed conversion ratio of N. sativa + C. longa treated groups (5A, 1.57, and 3A, 1.76) were higher than that of other nontreated groups. The gross and histopathological changes were much severe in control positive, but fewer changes were seen in treated groups. Therefore, we recommend that natural feed additives, black cumin (N. sativa) and turmeric (C. longa), act as an immune enhancer in broilers against P. multocida.

Elucidating antiviral activity of Curcuma longa against H9 N2 influenza virus using embryonated chicken egg model

@#Curcumin is a potent antimicrobial herb used traditionally as a spice in culinary. This study was designed to evaluate the antiviral effects of curcuma longa extract against H9 influenza virus. A total of 60 embryonated eggs were equally divided into 5 groups with 12 eggs in each group. Group 1 (G1) served as uninfected negative control. Whereas Group 2 (G2) was kept as positive control infected with known virus @ 0.2 ml with 10-9.3 EID50. Group 3 (G3) was offered Curcuma longa @ 0.2 mg/0.2 ml and H9N2 virus (@ 0.2 ml with 10-9.3 EID50. Similarly, Group 4 (G4) was inoculated with extract of Curcuma longa @ 0.2 mg/0.2 ml per egg, whereas Group 5 (G5) was given Ribazole @ 0.2 ml/ egg. The crude extract and virus were administered on the 15th day of incubation and were checked after every 24 hours up to 96th hour post inoculation by random selection of 3 eggs. Death and survival rate were noted in all groups. Gross and histopathological lesions were also observed. Results revealed that Curcuma longa extract had significantly (p<0.05) reduced the mortality rate of embryos infected with H9N2 virus. In G3, increased lymphocytes and mild fatty changes were seen in liver. Whereas, mature RBCs, plasma cells and some lymphoblast’s were observed in Spleen. Similarly, the bursa follicles were with lymphocytic aggregation. The G4 (Curcuma longa) and G5 (Ribazole) were with maximum embryo survival after 48 and 72 h post inoculation. This study revealed potential antiviral activity of Curcuma longa against H9N2 influenza viruses and can be opted as alternative to antibiotics and antiviral drugs to minimize the antimicrobial resistance in human and animal population.

Adaptation to host-specific bacterial pathogens drive rapid evolution of novel PhoP/PhoQ regulation pathway modulating the virulence.

The presence of the PhoP-PhoQ system is usually different in various bacterial groups, suggesting that PhoP can control the expression of different genes in species. However, little is known about the evolution of the PhoP-PhoQ system among bacterial pathogens. Here, we study the evolution of PhoP and PhoQ regulation in 15 species of Enterobacteriaceae family. We have determined that the regulatory objectives adopted by PhoP and PhoQ are mainly different, due to the result of horizontal gene transfer events and even the change in the genetic content between closely related species. We have compared many possibilities tests (M1 vs. M2 and M7 with M8) to determine the positive selection. Estimating parameters at M1 and M2, with positive selection in M2 of the two proteins. The proportions of positive selection sites significant with ω = 4.53076 for PhoP and ω = 4.21041 PhQ. M8 was significant for PhoP and PhQ proteins. To further confirm the positive selection results, we used the Selecton server to confer positive selection on individual sites using the Mechanistic-Empirical Combination model, and we noticed that several sites had been identified under selection pressure during the evolution. There was a strong indication for the positive selection in bacterial genes of PhoP and PhoQ showed the results. By the use of REL and IFEL, the positive selection for PhoP was detected 14 and 11 sites respectively at different codon positions. The positively selected sites of amino acids such as Arginine, Alanine, Lysine, and Leucine are more important for the production of signals. Our results suggest that the positive selection of PhoP-PhoQ genes in host adaptation during evolution raises an intriguing possibility causes subtle variations in actions of PhoP-PhoQ and also increases the opportunities that cause modification in protein structure for the evolution of increasing pathogenicity in bacterial pathogens.

Pathogenesis and tissue tropism of Newcastle disease virus and avian influenza virus (H9N2) in single and mixed infections.

Newcastle disease (ND) and avian influenza (AI) are globally considered as a serious threat to the chicken and other avian species. The paramyxovirus type 1 and orthomyxovirus type A are RNA viruses, which cause ND and AI infection, respectively.

Efficacy of commercial vaccines against the prevalent strains of Newcastle disease and avian influenza (h9n2) infections in broilers in Pakistan.

TThe efficacy of the two commonly used commercial vaccines for Newcastle disease (ND) and low path avian influenza (LPAI) H9N2 were evaluated against field virus in broiler chicks. One hundred one-dayold commercial broiler chicks were divided into four groups (A to D) with an equal number of birds per group. Group A and B were vaccinated against H9N2 and NDV, respectively, at day 7 of age while group C served as positive infected control for H9N2 and group D for NDV. Serum samples from birds in all groups were tested for presence of antibodies against H9N2 and NDV at day 21 of age. Subsequently, on day 28 of age, groups A and C were challenged with the field strain of H9N2 virus, and Group B and D with NDV. Birds were monitored for a period of 2 weeks for development of any clinical signs and mortality. The geometric mean titer were high in groups A (4.90) and B (7.3), and low in the unvaccinated groups C (0.7) and D (1.1). The highest and lowest value of H9N2 antibody titer detected through ELISA were 1.498 and 0.502, respectively. The S/P ratios greater than 0.5 were considered positive. The highest and lowest value for NDV antibody titer detected through ELISA were 783 and 882, respectively. Serum samples with titer greater than 396 were considered positive and indicated vaccination or other exposure to NDV. On histological examination severe congestion, necrosis, degeneration, hemorrhages and leukocyte infiltration were observed in intestine, lungs, trachea and bursa of Fabricius of the non-vaccinated group post-infection. Mild tissues changes were observed in the vaccinated group. It can be concluded from the findings that the commonly used commercial vaccines may provide effective protection against the circulating H9N2 and ND virus in broiler birds by producing protective antibody titer.