Newcastle disease (ND) is caused by the avian paramyxovirus type 1 (APMV-1) or Newcastle disease virus (NDV) that comprises a diverse group of viruses with a single-stranded, negative-sense RNA genome. ND is one of the most important diseases of chickens, because it severely affects poultry production worldwide. In the 1970s, outbreaks of virulent ND were recorded in Brazil, and the strain APMV-1/Chicken/Brazil/SJM/75 (SJM) of NDV was isolated. This strain was characterized as highly pathogenic for chickens but not pathogenic for other bird species. Here we present the complete genome of NDV strain SJM and investigate the phylogenetic relationships of this virus with other NDV strains in terms of genome and proteins composition, as well as characterizing its evolution process. The NDV strain SJM is categorized as a velogenic virus and the complete genome is 15,192 nucleotides in length, consisting of six genes in the order 3′-NP-P-M-F-HN-L-5′. The presence of the major pathogenic determinant of NDV strains (¹¹²R-R-Q-K-R↓F¹¹⁷) was identified in the Fusion protein of the NDV strain SJM. In addition, phylogenetic analysis classified the NDV strain SJM as a member of class II, genotype V, and indicates that this virus help us in the understanding of the evolutionary process of strains belonging to this genotype. This study contributes to the growing interest involving the characterization of NDV isolates to improve our current understanding about the epidemiology, surveillance and evolution of the pathogenic strains.

A competitive liquid-phase–blocking concanavalin A enzyme-linked immunosorbent assay (LPB-ConA-ELISA) was developed in the current study. The assay used ConA as a capture reagent, and the sera of specific pathogen–free chickens immunized with nonpurified Newcastle disease virus (NDV) suspension as detector antibodies, to detect and quantify specific antiviral antibodies in serum samples from free-ranging pigeons. The comparison between the LPB-ConA-ELISA and the hemagglutination inhibition (HI) test for the detection of antibodies in serum samples from 107 pigeons showed significant correlation between the assays (r = 0.875), a high sensitivity (100%), specificity (95.8%), accuracy (96.3%) for the ELISA, and good agreement (κ = 0.83) between the 2 assays. The results of this study suggest that the LPB-ConA-ELISA could be a useful alternative to HI test in the serodiagnosis of NDV in pigeons, or other species of birds.

Starch overload in horses causes gastrointestinal and metabolic disorders that are associated with microbiota changes. Therefore, we identified the fecal microbiota and hypothesized that intracecal injection of alkaline solution (buffer; Mg(OH)₂ + Al(OH)₃) could stabilize these microbiota and clinical changes in horses submitted to corn starch overload. Ten crossbred horses (females and geldings) were allocated to group I (water–saline and starch–buffer treatments) and group II (water–buffer and starch–saline treatments). Clinical signs, gross analysis of the feces, and fecal microbiota were evaluated through 72 h (T0; T8; T12; T24; T48; T72). Corn starch or water were administrated by nasogastric tube at T0, and the buffer injected into the cecum at T8 in starch–buffer and water–buffer treatments. Starch overload reduced the richness (p < 0.001) and diversity (p = 0.001) of the fecal microbiota. However, the starch–buffer treatment showed greater increase in amylolytic bacteria (Bifidobacterium 0.0% to 5.6%; Lactobacillus 0.1% to 7.4%; p < 0.05) and decrease in fibrolytic bacteria (Lachnospiraceae 10.2% to 5.0%; Ruminococcaceae 11.7% to 4.2%; p < 0.05) than starch–saline treatment. Additionally, animals that received starch–buffer treatment showed more signs of abdominal discomfort and lameness associated with dysbiosis (amylolytic r > 0.5; fribolytic r < 0.1; p < 0.05), showing that cecal infusion of buffer did not prevent, but intensified intestinal disturbances and the risk of laminitis.

Evidence based on genomic sequences is extremely important to confirm the phylogenetic relationships within the Rhizobium group. SEMIA3007 was analyzed within the Mesorhizobium groups to define the underlying causes of taxonomic identification. We previously used biochemical tests and phenotypic taxonomic methods to identify bacteria, which can lead to erroneous classification. An improved understanding of bacterial strains such as the Mesorhizobium genus would increase our knowledge of classification and evolution of these species. In this study, we sequenced the complete genome of SEMIA3007 and compared it with five other Mesorhizobium and two Rhizobium genomes. The genomes of isolated SEMIA3007 showed several orthologs with M. huakuii, M. erdmanii and M. loti. We identified SEMIA3007 as a Mesorhizobium by comparing the 16S rRNA gene and the complete genome. Our ortholog, 16S rRNA gene and average nucleotide identity values (ANI) analysis all demonstrate SEMIA3007 is not Rhizobium leguminosarum bv. viceae. The results of the phylogenetic analysis clearly show SEMIA3007 is part of the Mesorhizobium group and suggest a reclassification is warranted.

Sustainable agriculture relies on effective soil management, making it crucial to assess soil health, especially in areas of agricultural expansion, such as the Cerrado in the MATOPIBA region. Sustainable strategies, such as integrated production systems (crop–livestock–forestry), are essential to mitigate these impacts. However, little is known about the effects of these systems on soil microbial communities. The objective of this study was to evaluate bacterial communities associated with soils under different integrated production systems in the MATOPIBA region. Soil samples from the 0–10 cm depth layer were collected from the following land use systems: (i) native Cerrado vegetation (NCV), (ii) native Babassu forest (NPV), (iii) no-tillage soybean—regional standard system (NT-S), (iv) crop–forest integration (CFI), (v) crop–livestock integration (CLI), and (vi) livestock–forest integration (LFI). We measured chemical properties and bacterial communities using next-generation sequencing (NGS) of the V3-V4 hypervariable region of the 16S rRNA gene. The results revealed that the integration systems (CFI, CLI, and LFI) resulted in changes in soil chemical properties, which contributed to the modulation of the bacterial communities. The most abundant taxa in integrated production systems shows a positive correlation with soil pH and phosphorus content. Members of the Nitrosomonadaceae and Sphingomonadaceae families are more related to integrated production systems containing a forestry component (CFI and LFI), while Bacillaceae are more evident in crop–livestock integration systems (CLI).