Infectious diseases are the critical problems of the world as a result of the emergence of different antimicrobial resistant microorganisms due to several reasons like misuses and repeating uses of antibiotics. Because of this, searching of new treatment method is important from natural substances to against those infectious diseases in both human and animals’ aspects. Among those plants, Sida rhombifolia has various roles against those infectious diseases through its different phytochemical components. The objectives of this study were assessing the antibacterial activity of the aqueous-methanol extract of the plant’s aerial part and knowing the phytochemical constituents of the plant. Preliminary phytochemical screening revealed that the extract of S. rhombifolia’s aerial part possesses flavonoids, alkaloids, polyphenols, and quinines. In addition to this, the antibacterial activity of the plant extract was evaluated on five pathogenic bacteria species using agar well diffusion method at different concentrations of plant extracts. Minimum inhibition concentration and minimum bactericidal concentration determinations were done by tetrazolium chloride microtiter dilution assay. The inhibition zone of mean diameters ranging from 0.00 to 7.67mm against all test bacteria was significantly (p<0.05) much less than that of the positive control Chloroamphinicole (30μg/disc) with the range of 14.33mm-15mm of inhibition zone of diameters. The inhibition zones of the tested bacteria at the concentration of 62.5mg/ml were much less than the higher concentration (500mg/ml) and significantly different (p<0.05), whereas the MIC value ranges from 4.62 to 97.22mg/ml and the MBC value ranges from 4.62 to 125.00mg/ml. Even if the plant extract showed antibacterial activity, it was lower than that of other solvent extraction methods; so other solvent extraction methods and fractionates must be conducted to investigate the antibacterial activities of the plant extract on different bacterial strains and species that cause different diseases.

Marek’s disease virus (MDV) is a highly contagious, immunosuppressive, and oncogenic chicken pathogen causing marek’s disease (MD). In this outbreak-based study, 70 dual-purpose chickens that originated from poultry farms in Northwest Ethiopia and suspected of MD were sampled for pathological and virological study from January 2020 to June 2020. Clinically, affected chickens showed inappetence, dyspnea, depression, shrunken combs, and paralysis of legs, wings, and neck, and death. Pathologically, single or multiple greyish white to yellow tumor-like nodular lesions of various size were appreciated in visceral organs. In addition, splenomegaly, hepatomegaly, renomegaly, and sciatic nerve enlargement were observed. Twenty-seven (27) pooled clinical samples i.e. 7 pooled spleen samples and 20 pooled feathers samples were aseptically collected. Confluent monolayer of Chicken Embryo Fibroblast cells was inoculated with a suspension of pathological samples. Of this, MDV-suggestive cytopathic effects were recorded in 5 (71.42%) and 17 (85%) pooled spleen and feather samples respectively. Molecular confirmation of pathogenic MDV was conducted using conventional PCR amplifying 318 bp of ICP4 gene of MDV-1, of which, 40.9% (9/22) tested positive. In addition, 5 PCR-positive samples from various farms were sequenced further confirming the identity of MDV. The ICP4 partial gene sequences were submitted to GenBank with the following accession numbers: OP485106, OP485107, OP485108, OP485109, and OP485110. Comparative phylogenetics showed, two of the isolates from the same site, Metema, seem to be clonal complexes forming distinct cluster. The other three isolates, two from Merawi and one from Debretabor, appear to represent distinct genotypes although the isolate from Debretabor is closer to the Metema clonal complex. On the other hand, the isolates from Merawi appeared genetically far related to the rest of the 3 isolates and clustered with Indian MDV strains included in the analysis. This study presented the first molecular evidence of MDV in chicken farms from Northwest Ethiopia. Biosecurity measures should strictly be implemented to hinder the spread of the virus. Nationwide studies on molecular characteristics of MDV isolates, their pathotypes, and estimation of the economic impact associated with the disease may help justify production and use of MD vaccines within the country.

Background: Calpurnia aurea (Ait.) Benth. leaves are used to treat different diseases like ectoparasite infestation, diarrhea, sores, anthrax, fevers, pain, and snake venom. The leaves of Calpurnia aurea were first extracted by methanol and further fractionated with the help of n-hexane, dichloromethane and ethyl acetate with increasing polarity. Methods: The antibacterial activities of the fractions were evaluated against disease causing bacteria using agar well diffusion. The minimum inhibitory concentrations (MIC) of the fractions were determined by the micro-broth dilution method using tetrazolium salt colorimetric assay. The antioxidant activities of the solvent fractions were determined by phospho-molbedum reduction assay, reducing power assay and hydroxyl radical scavenging activity. Results: The average MIC value of C. aurea fractions ranged from 1.95mg/mL to 31.25mg/mL, 7.81mg/mL to 31.25mg/mL and 13.02mg/mL to 62.5mg/mL, for ethyl acetate, dichloromethane and n-hexane fractions, respectively. The leaf extracts have a higher antioxidant effect, as shown in the phospho-molbedum reduction assay, reducing power and hydroxyl radical scavenging assay. Conclusion: The ethyl acetate and dichloromethane fractions revealed significant antibacterial effects against the growth of pathogenic bacteria. However, the n-hexane fraction showed the least antibacterial effect against all of the test bacteria. Furthermore, the n-hexane fractions of C. aurea showed higher antioxidant activity.

Introduction: The present trial aimed to investigate invitro anthelminthic activities of selected tropical tanniferous plant extract on egg hatchability and larval development inhibition of Haemonchus contortus in sheep. In view of that, three tropical tanniferous plants Rhus glutinosa, Syzygium guineensa and Albizia gumifera, were selected based on their relative high content of condensed tannins. Methods: In this study, eggs were collected from artificially infected with H. contortus. Then the egg was directly subjected to invitro assay with these condensed tannin-enriched extracts using egg hatchability assay and inhibition of larval development assay. Results: The result showed that extracts from all three tropical tanniferous plants demonstrated statistically significant (P < 0.05) dosedependent inhibition of both egg hatchability and larval development. According to IC50 and IC90 values, the condensed tannin-enriched extracts inhibiting egg hatching and larval development most potently were Rhus glutinosa followed in descending order of activity by Syzygium guineensa and Albizia gumifera. Discussion: The result of this study showed that these condensed tanninenriched extracts were effective in inhibiting egg hatchability as well as larval development. Therefore, condensed tannin might be recommended as one of the options for the control of H. contortus in sheep.

Avian infectious bronchitis virus is a highly contagious disease occurring in respiratory, urogenital, and reproductive tissues of chicken causing considerable losses due to death, egg drop, and reduced production. This preliminary study was conducted to investigate the prevalence of antibodies against infectious bronchitis virus (IBV) and to assess the potential risk factors in chickens of northwest Ethiopia. A cross-sectional study was conducted from November 2020 to June 2021. A total of 768 serum samples from three zones were collected. To investigate the presence of antibodies against IBV, the indirect ELISA serological test was applied. Positivity for anti-IBV antibodies was observed in 23.96% (95% CI: 20.98–27.14) of the samples. The mixed-effect logistic regression analysis of potential risk factors showed that IBV prevalence was significantly higher in young chickens than adults ( ) and higher in intensive farm type than in extensive type ( ). Based on the production purposes of the chickens, the odds of seropositivity for IB was significantly higher in layers than in broilers ( ) and dual purposes ( ). This study revealed higher seroprevalence in farms which had the “all-in-all-out” rearing method than in farms with different batches in one house with a significant difference ( ), higher seroprevalence in the poor ventilated type than in good ones ( ), and higher seroprevalence in the houses that did not remove used litter at all than houses of completely disposed and partially disposed litter ( ). Moreover, disinfection of houses had significant effect on the occurrence of IB. Having personal protective equipment was significantly affecting the occurrence of IB, being higher in the farms that have no wearing clothes and shoe than in those having wearing clothes and shoe ( ). In conclusion, the seroprevalence finding in the present study indicated that the organism is circulating among the population of chickens and high enough to cause significant economic losses Therefore, poultry houses should be cleaned, disinfected, and well ventilated and farm attendants should have separate farm shoe and clothes. Further studies on the virus isolation and molecular characterization of the target gene are needed in the study area.

Haemonchosis is a major gastrointestinal parasitic infection in sheep caused by H. contortus. An abattoir-based cross-sectional study was conducted from January to September 2024 to assess the haematobiochemical alterations and lesion characterization induced by haemonchosis in slaughtered sheep at Gondar ELFORA abattoir. The study involved 60 male local breed sheep, divided into 30 infected and 30 non-infected controls. The selection process involved postmortem examination of the abomasum tissues, incision, palpation, and visual inspection. Blood samples were taken for haematology and serum biochemical profiles, and a three cm tissue sample with typical H. contortus lesions was also taken. The study found significant reductions in hemoglobin, hematocrit, corpuscular volume, hemoglobin, and red blood cell counts in the infected group compared to the non-infected group. However, white blood cells, monocytes, neutrophils, and eosinophils were significantly higher in the infected group. Biochemical parameters showed significant reductions in total protein, albumin, globulin, and albumin-to-globulin ratio in the infected group. Erythrocyte indices indicated microcytic normochromic anemia. Gross examination revealed hemorrhages, dark brown abomasal contents, blood streaks, and a nodular lesion. Microscopic analysis revealed tissue-dwelling worms, submucosal hemorrhage, mucosal gland hyperplasia, thickened muscularis, and hyperplastic abomasal glands. The alterations in haematobiochemical parameters support the findings from gross and microscopic lesions. Thus, integrating haematobiochemical analysis with gross and microscopic lesion characterization improves the diagnosis of haemonchosis. Due to hypoproteinemia observed, it is advisable to supplement helminth-infected animals with protein-rich feeds, such as legumes.