Foot-and-mouth disease virus dynamics in border areas of Pakistan with Afghanistan

BACKGROUND

Foot and mouth disease (FMD) is a highly contagious disease that impacts cloven-hoofed animals globally. The illegal trade of livestock between the border regions of Pakistan and Afghanistan can contribute to the spread of this disease. This study focuses on investigating the outbreaks of FMD that occurred in this area from June 2020 to May 2021.

METHODS

RESULTS: A total of 233 epithelial tissue samples were collected, and 77% were found positive for FMDV through an antigen-detection by ELISA and molecular conformation through RT-PCR. The study found three serotypes of FMDV dominating in the border area of Pakistan with Afghanistan: O, A, and Asia-1. The outbreak activity was peaked between August/September followed by July/October 2020. Phylogenetic analysis conducted using the VP1 region sequence showed that serotype O isolates belonged to the Middle East-South Asia (ME-SA) topotype, PanAsia-2 lineage, and ANT-10 sub-lineage, while serotype Asia-1 isolates belonged to a novel lineage BD-18.The highest prevalence of serotype O of FMDV was found in cattle and buffalo of 1-2 year age group, while the highest outbreak ratio of serotype O was recorded in goats of 0-1 year age group and sheep of > 2 year age group. The serotype O was more prevalent in male than female sheep. The type A was more prevalent in females of sheep and goats than their corresponding males. The serotype Asia-1 was more prevalent in females of cattle and sheep than their corresponding males. The outbreak epidemiology of FMD varied significantly between various regions, months of study, animal species, age groups, and gender.

CONCLUSIONS

The study found that FMD outbreaks in the border area of Pakistan and Afghanistan were diverse and complicated, and that different types of FMDV were circulating. The study recommended effective actions to stop FMD transmission in this area.

An appraisal of traditional knowledge of plant poisoning of livestock and its validation through acute toxicity assay in rats

Background: Kashmir Himalaya hosts the most diverse and rich flora in the world, which serves as grazing land for millions of small ruminants in the area. While most plant species are beneficial, some can be poisonous, causing economic losses and animal health issues for livestock. Consequently, this study is the first comprehensive report on the traditional phyto-toxicological knowledge in District Muzaffarabad and the assessment of its authenticity through experimental studies in rats. Methods: The data regarding traditional knowledge was gathered from 70 key respondents through semi-structured interviews, which was quantitatively analyzed and authenticated through plant extract testing on Wistar female rats and comparison with published resources. Results: A total of 46 poisonous plant species belonging to 23 families and 38 genera were reported to be poisonous in the study area. Results revealed that leaves were the most toxic plant parts (24 species, 52.1%), followed by the whole plant (18 species, 39.1%), stem (17 species, 36.9%), and seeds (10 species, 21.7%). At the organ level, liver as most susceptible affected by 13 species (28.2%), followed by the gastrointestinal tract (15 species, 32.6%), nervous system (13 species, 8.2%), dermis (8 species, 17.3%), renal (7 species, 15.2%), respiratory (4 species, 8.7%), cardiovascular system (3 species, 6.5%), and reproductive system (2 species, 4.3%). The poisonous plant species with high Relative frequency citation (RFC) and fidelity level (FL) were Nerium oleander (RFC, 0.6; FL, 100), Lantana camara (RFC, 0.6; FL, 100), and Ricinus communis (RFC, 0.6; FL, 100). Experimental assessment of acute toxicity assay in rats revealed that Nerium oleander was the most toxic plant with LD50 of (4,000 mg/kg), trailed by Ricinus communis (4,200 mg/kg), L. camara (4,500 mg/kg), and Datura stramonium (4,700 mg/kg); however, other plants showed moderate to mild toxicity. The major clinical observations were anorexia, piloerection, dyspnea, salivation, tachypnea, constipation, diarrhea, tremor, itchiness, and dullness. Conclusion: This study showed that numerous poisonous plants pose a significant risk to the livestock industry within Himalayan territory, leading to substantial economic losses. Consequently, it is of utmost importance to conduct further comprehensive studies on the phytotoxicity of plants.

Phytotoxicological study of selected poisonous plants from Azad Jammu & Kashmir

Poisonous plants cause tremendous economic losses to the livestock industry. These economic losses are deterioration in their health, decreased productivity, deformed offspring, and reduced longevity. The current study is the first comprehensive report on poisonous plants of Azad Jammu and Kashmir which systematically documents the phytotoxicological effect and mode of action in livestock. The information was gathered from 271 informants including 167 men and 104 women through semi-structured interviews and literature search through available databases. The data collected through interviews was analyzed with quantitative tools viz. the factor informant consensus and fidelity level. A total of 38 species of flowering plants belonging to 23 families and 38 genera were reported. Family Asteraceae (5 spp) was the most dominant, followed by Solanaceae (4 spp), Fabaceae (4 spp), Euphorbiaceae (4 spp) and Convolvulaceae (3 spp). Among all the species collected, herbs were the dominant life form (22 spp, 57.89%), trailed by shrubs (11 spp, 28.95%), and trees (5 spp, 13.16%). Whole plant toxicity was reported to be the highest (15 spp, 39.47%), followed by leaf toxicity (12 spp, 31.58%), seed toxicity (4 spp, 7.89%), fruit toxicity (3 spp, 10.53%), latex toxicity (2 spp, 5.26%), flowers toxicity (1 spp, 2.63%), and berries toxicity (1 spp, 2.63%). The most toxic route of administration was found oral (39 spp, 40.63%), followed by intraperitoneal (24 spp, 25%), and intravenous (21 spp, 21.88%). The most commonly affected organ was found liver (20.41%), followed by gastrointestinal tract (20.341%), CNS (16.33%), skin (14.29%), kidneys (12.24%), lungs (4.04%), reproductive organs (2.04%), spleen (1.75%), blood (1.75%), heart (1.75%), urinary tract (1.75%), and pancreas (1.75%). The maximum Fic value was found for dermatological disorders (0.91), followed by the endocrine system (0.90), gastrointestinal (0.82), neurology (0.77), nephrology (0.67), cardiovascular (0.67), urinary (0.67), respiratory (0.60), sexual (0.60) disorders. Senecio vulgaris, and Ageratum conyzoides were the most important plants with fidelity level (0.95) and (0.87). Nerium oleander, Lantana camara, Leucaena leucocephala, and Ricinus communis were the important poisonous plant with maximum fidelity level (100%). Ricinus communis with reported lowest LD50 (<20 mg/kg) was the top-ranked poisonous plant followed by Lantana camara and Justicia adhatoda (25-50 mg/kg), Nerium Oleander (157.37 mg/kg), and Datura innoxia (400 mg/kg). We found that knowledge about poisonous plants is less prevailing in the rural areas of Azad Kashmir compared to the knowledge about medicinal plants and poisonous nature of reported plants is due to production of toxic substances and presence of essential oils.

Prevalence of avian influenza H5, H7, and H9 viruses in commercial layers in Karachi, Pakistan

BACKGROUND

Avian influenza viruses (AIVs) cause significant harm to the poultry industry due to mortality as well as high morbidity along with the risk of potential zoonotic transmission to humans.

AIMS

The study aimed to investigate the prevalence of influenza H5, H7, and H9 viruses and their co-infections in layers having respiratory distress such as sneezing, coughing, and tracheal rales.

METHODS

Totally, 960 tracheal swabs (240 swabs in each season) were collected from 120 poultry flocks, including 10 farms per month and 8 samples per flock, located in Karachi where the outbreaks were reported. The samples were confirmed through antigen ELISA and subtyped by RT-PCR.

RESULTS

Antigen ELISA revealed that the prevalence of avian influenza viruses was 26.45%; however, seasonal differences were not significant (P<0.05). RT-PCR subtyping of hemagglutinin (HA) gene revealed the higher prevalence of H9 virus (40.16%) as compared to H7 virus (5.51%) and H5 virus (4.73%). The co-infections comprised H5/H7/H9 (37.0%) and H5/H9 (12.6%).

CONCLUSION

This study shows that AI is endemic in layer farms in Karachi where the H9 subtype is predominant along with co-infections of H5/H7/H9 subtypes.

Protective effect of selenomethionine on aflatoxin B1-induced oxidative stress in MDCK cells

AFB1 is a mycotoxin which exerts their cytotoxicity through increasing oxidative damage in target organ. Kidney is one of target organs vulnerable to damage caused by AFB1. In this study, Madin-Darby canine kidney (MDCK) cells were used to evaluate the AFB1-induced cell damage by the MTT assay. The results revealed that the toxic effect of AFB1 on MDCK cells is both dose and time dependent. Half maximal toxic concentration (IC50) was noted at 0.25 μg/ml of AFB1. Further, protective effect of six different concentrations (0.2, 0.8, 1, 2, 4, and 8 μM) of selenomethionine (SeMet) was observed against 0.25 μg/ml of AFB1-induced damage. The results showed that 0.25 μg/ml of AFB1 caused significant increase in oxidative stress, which was demonstrated by significant increase of malondialdehyde (MDA) level, reduction of intracellular GSH level, as well as GPX1 activity and mRNA level in MDCK cells when compared with control. SeMet protected the cells from AFB1-induced oxidative damage in a dose-dependant manner. Good protection could be achieved between 1 and 4 μM of concentration. Amid this range, MDA level significantly decreased while intracellular GSH level and GPX1 activity in addition to mRNA level significantly increased. Moreover, cell viability was significantly improved. It could be concluded that SeMet is a potential antioxidative agent to alleviate AFB1-induced oxidative stress.

Potential of adenovirus and baculovirus vectors for the delivery of shRNA against morbilliviruses

Morbilliviruses are important pathogens of humans, ruminants, carnivores and marine mammals. Although good vaccines inducing long-term immunity are available, recurrent outbreaks of measles, canine distemper and peste des petits ruminants (PPR) are observed. In control strategies, antivirals thus could be useful to confine virus spread and application of interfering RNAs is a promising approach, provided they can be delivered efficiently into the host cells. We have constructed recombinant adenovirus and baculovirus vectors expressing short hairpin RNAs (shRNAs) against the PPR virus (PPRV) and compared them in vitro. It was found that both recombinant viruses inhibited PPRV replication with the baculovirus vector, which inhibited generation of infectious progeny by more than 2 log10 and the nucleoprotein expression of PPRV by 73%, being the more efficient. The results show that baculoviral shRNA-expressing vectors have the potential for therapeutic use against morbillivirus infections.