Shigatoxigenic and enteropathogenic Escherichia coli with virulence and multidrug resistance profile were isolated from Nile tilapia. This study finding is of great importance to public health because they help understand this pathogen epidemiology in fish and demonstrate how these animals can transmit E. coli related diseases to humans.

Swine can be infected by bovine viral diarrhea virus (BVDV). However, transmission routes among pigs are still unknown. The objective of the present study was to induce experimental infection of BVDV-1 in weaned piglets and to assess the potential transmission through pen back pond water, used to facilitate heat exchange of the pigs housed in barns. Two repetitions (BP1 and BP 2) were performed using 12 piglets proven to be free BVDV (n=6 per repetition) allocated into three groups: control, sentinels and infected with two piglets each. The piglets were placed in stainless steel isolators. The infected group received an inoculum containing BVDV-1, Singer strain. The piglets remained in the cabinets for 25 days, during which samples of nasal swab were collected daily and blood sampled weekly. At the end, the piglets were euthanized, necropsied and organ fragments were collected for histopathology, immunohistochemistry and RT-PCR. In the first experiment (BP1) the infected animals shed the virus between days 6 and 21 post-infection. Regarding the sentinel group, shedding occurred in only one piglet, on the 20th day after infection, and seroconversion was observed on the 25th day post-infection. In BP2, infected piglets I3 and I4 shed the virus on days 4 and 21 post-infection, respectively. Only one sentinel piglet (S3) she the virus on day 13 post-infection. Therefore, it was concluded that pigs can become infected with BVDV-1 and shed potentially infectious viral particles consequently, being able to transmit the virus to other pigs through back pond water.

The sweetpotato (Ipomoea batatas L., Convolvulaceae family) originated in Latin America and is currently cultivated worldwide. The storage roots, rich in calories, have made this crop one of the main caloric sources for low-income populations, especially in developing countries. Brazil annually produces about 805,000 tons, with the Northeast region responsible for 34% of this production (Albuquerque et al. 2020). In October 2019, sweetpotato plants cv. Campina, from a field in the region of Touros, state of Rio Grande do Norte (RN), Brazil (5°12’31”S 35°34’42”W), presented deformed storage roots, with galls, typical of root-knot nematodes. The roots were sent to the Nematology Laboratory (LabNema) where 14,032 eggs and 3,312 second-stage juveniles (J2s) of Meloidogyne sp., in 10 g of roots, were recovered. The species of adults was identified through morphological, biochemical, and phylogenetic analysis. The perineal region of females (n = 10) presented an oval shape, with a high and semi-trapezoidal dorsal arch and streak-free perivulval region. The labial region of males (n=10) presented high and rounded head cap, labial region slightly set off from the body, without annulations. The morphological characters were compatible with the original description of Meloidogyne enterolobii (Yang and Eisenback 1983). The phenotype of esterase isoenzymes showed two major bands (VS1-S1) also characteristic of M. enterolobii (Esbenshade and Triantaphyllou 1985). Sequences of 18S rDNA (~1200bp) of individual females (Holterman et al. 2006) obtained from sweetpotatoes before (SPme1 and 2) and after inoculation (SPme3 and 6), and from guava, used as M. enterolobii species control, were submitted to Bayesian analysis. The sequences presented genetic diversity among them resulting from seven SNPs (Single Nucleotide Polymorphism) and 99.4 to 99.9% identity with M. enterolobii sequences deposited in the NCBI GenBank (accession numbers MW209034-MW209039). The pathogenicity test was carried out under greenhouse conditions, in which 3,000 eggs and J2s from the original population isolated of M. enterolobii were inoculated in sweetpotato seedlings cv. Campina (n = 6). After three months, the roots presented galls and deformations typical of root-knot nematodes, while non-inoculated plants did not present any symptoms. An average of 15,900 eggs and J2s of M. enterolobii (RF = 5.3) were recovered from the roots, proving that sweetpotatoes were a host of this species. Meloidogyne enterolobii is known to cause great damage to sweetpotato (Ye et al. 2020). In Brazil, Meloidogyne nematode had been reported once, isolated from a sweetpotato field in the Ceara state and the species suggested by the authors according to esterase electrophoresis was M. enterolobii. Nonetheless, the authors did not present taxonomic, isoenzyme phenotypes and molecular species identification integratively, nor included pathogenicity tests (Silva et al. 2016). Therefore, it is the first time that M. enterolobii, with reliable identification by different methods, including sequencing, was detected in commercial sweetpotato fields in the RN state and in Brazil. The local farmers reported that this nematode deforms the storage roots which make them useless for commercialization, resulting in minimal losses of 50% of production in the infested areas. Furthermore, as sweetpotatoes are vegetatively propagated, the spread of this nematode through planting material is favored. Considering the importance of this crop in Brazil, this report is essential for control measures of this pathogen to be taken in order to avoid its spread to other regions.

In 2019, during a nematologic survey in Jaboticabal, Brazil, root-knot nematode Meloidogyne incognita parasitizing hops ( Humulus lupulus ) was identified with based on morphological characters of adults, esterase phenotypes ( n = 16), and molecular analysis. Modified Koch’s postulates was carried out and after 90 days, the average total population recovered had different stages of development, with a reproductive factor (RF) of 4.81. This is the first report of H. lupulus as a host of M. incognita in the state of São Paulo and in Brazil.

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