Deoxynivalenol concentrations in feed ingredients and swine diets measured by enzyme-linked immunosorbent assay and high-performance liquid chromatography

The objective was to compare deoxynivalenol (DON) concentrations in feed ingredients and commercial swine diets measured by enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC). Seventy feed ingredient samples consisted of corn, corn dried distillers grains with solubles, corn gluten feed, corn gluten meal, palm kernel expellers, rice bran, soy hulls, soybean meal, and wheat. Commercial swine diet samples (n = 92) were collected from 23 swine farms of varying regions in Korea and different growth stages of pigs. The DON concentration of all samples was determined in duplicate. Statistical comparisons were performed to compare the analytical methods (ELISA vs. HPLC), diet phases, and regions. The DON concentrations in most ingredients and all diets determined by ELISA method were greater than those determined by HPLC. The DON concentrations determined by the ELISA method were less than 1 mg/kg in all ingredients except corn dried distillers grains with solubles and corn gluten feed, and those determined by the HPLC were less than 0.5 mg/kg in all ingredients. The DON concentrations in complete diets did not vary by region or growth stages of pigs. The DON concentrations in most feed ingredients and commercial swine diets determined by ELISA method are greater than those determined by HPLC, but does not vary by regions in Republic of Korea or pig growth stages.

Impact of nitrogen and phosphorus fertilizers on Cry1Ac protein contents in transgenic cotton / Impacto de fertilizantes de nitrogênio e fósforo nos conteúdos de proteína Cry1Ac em algodão transgênico

Abstract Application of different fertilizers to check the efficiency of expression of Bt (Bacillus thuringiensis) gene in one of the leading commercialized crops (cotton) against Lepidopteran species is of great concern. The expression of Cry protein level can be controlled by the improvement of nutrients levels. Therefore, the myth of response of Cry toxin to different combinations of NP fertilizers was explored in three Bt cotton cultivars. Combinations include three levels of nitrogen and three levels of phosphorus fertilizers. Immunostrips and Cry gene(s) specific primer based PCR (Polymerase Chain Reaction) analysis were used for the presence of Bt gene that unveiled the presence of Cry1Ac gene only. Further, the ELISA (enzyme-linked immunosorbent assay) kit was used to quantify the expression of Cry1Ac protein. Under various NP fertilizers rates, the level of toxin protein exhibited highly significant differences. The highest toxin level mean was found to be 2.3740 and 2.1732 µg/g under the treatment of N150P75 kg ha-1 combination while the lowest toxin level mean was found to be 0.9158 and 0.7641 µg/g at the N50P25 kg ha-1 level at 80 and 120 DAS (Days After Sowing), respectively. It was concluded from the research that the usage of NP fertilizers has a positive relation with the expression of Cry1Ac toxin in Bt cotton. We recommend using the N150P50 kg ha-1 level as the most economical and practicable fertilizer instead of the standard dose N100P50 kg ha-1 to get the desired level of Cry1Ac level for long lasting plant resistance (<1.5). The revised dose of fertilizer may help farmers to avoid the cross-resistance development in contradiction of insect pests.

Resumo A aplicação de diferentes fertilizantes para verificar a eficiência da expressão do gene Bt (Bacillus thuringiensis) em uma das principais culturas comercializadas (algodão) contra espécies de lepidópteros é uma grande preocupação. A expressão do nível de proteína Cry pode ser controlada pela melhoria dos níveis de nutrientes. Portanto, o mito da resposta da toxina Cry a diferentes combinações de fertilizantes NP foi explorado em três cultivares de algodão Bt. As combinações incluem três níveis de nitrogênio e três níveis de fertilizantes de fósforo. A análise de PCR (reação em cadeia da polimerase) específica para o gene (s) Immunostrips e Cry (s) foi usada para a presença do gene Bt que revelou a presença do gene Cry1Ac apenas. Além disso, o kit ELISA (ensaio de imunoabsorção enzimática) foi usado para quantificar a expressão da proteína Cry1Ac. Sob várias taxas de fertilizantes NP, o nível de proteína de toxina exibiu diferenças altamente significativas. A média do nível mais alto de toxina foi de 2,3740 e 2,1732 µg / g sob o tratamento da combinação N150P75 kg ha-1, enquanto a média do nível mais baixo de toxina foi de 0,9158 e 0,7641 µg / g no nível de N50P25 kg ha-1 em 80 e 120 DAS (dias após a semeadura), respectivamente. Concluiu-se com a pesquisa que o uso de fertilizantes NP tem relação positiva com a expressão da toxina Cry1Ac no algodão Bt. Recomendamos o uso do nível de N150P50 kg ha-1 como o fertilizante mais econômico e praticável em vez da dose padrão N100P50 kg ha-1 para obter o nível desejado de nível de Cry1Ac para resistência de planta de longa duração (<1,5). A dose revisada de fertilizante pode ajudar os agricultores a evitar o desenvolvimento de resistência cruzada em contradição com as pragas de insetos.

Crescimentos de fungos produtores de micotoxinas em grãos de amendoim / Growths of mycotoxin-producing fungi on peanut grains

O amendoim (Arachis hypogaea L.) é uma oleaginosa com alto valor energético e nutricional, servindo de substrato ideal para o crescimento de fungos durante o processo de colheita, estocagem e processamento dos grãos. As micotoxinas são originadas a partir do metabolismo secundário de fungos toxigênicos; quando essas toxinas são ingeridas, podem causar efeitos tóxicos em humanos e animais. O objetivo deste trabalho foi avaliar a contaminação fúngica em amostras de grãos de amendoim disponíveis para o consumo humano. Foram analisadas amostras de amendoim torrado na vagem, amendoim cru (in natura) e amendoim torrado sem a vagem. A metodologia utilizada foi o método de plaqueamento direto em placas de Petri, contendo o meio cultura Sabouraud Dextrose Ágar (SDA). Porções de 40 grãos de amendoim de cada amostra foram utilizadas para o teste. Os resultados obtidos foram expressos em quantidade de grãos que apresentaram crescimento fúngico em porcentagem. Para identificação ao nível do género das colônias fúngicas isoladas, foi efetuada uma observação microscópica das suas estruturas morfológicas. Em todas as amostras estudadas ocorreram o crescimento de fungos potencialmente micotoxigênicos. Os grãos de amendoim cru (in natura) sem a vagem foram os mais contaminados por fungos como Aspergillus sp. (20%), Alternaria sp. (13,1%), Penicillium sp. (13,3%) e Fusarium sp. (23,3%) quando comparados com os grãos torrados. A presença desses fungos nas amostras de amendoim indica a possibilidade de desenvolvimento de micotoxinas potencialmente tóxicas para o humano. O processo de torrefação inibe o crescimento de determinadas espécies de fungos micotoxigênicos.(AU)

Peanut is an oilseed with high energy and nutritional value, serving as an ideal substrate for the growth of fungi during the process of harvesting, storing and processing the grains. Mycotoxins originate from the secondary metabolism of toxigenic fungi; when ingested, they can cause toxic effects in humans and animals. The objective of this work was to evaluate the fungal contamination in samples of peanut grains available for human consumption. The methodology used was the direct plating method in Petri dishes containing Sabouraud Dextrose Agar (SDA) culture. Portions of 40 peanut kernels from the samples were immersed in a 0.4% sodium hypochlorite solution for two minutes for surface disinfection, then rinsed once in distilled water. Incubation was carried out at room temperature for 7 days and the results were expressed as the amount of grains that showed fungal growth in percentage. To identify the colonies of isolated filamentous fungi at the genus level, a microscopic observation of their morphological structures was carried out, which consists of removing a sample from the edge of the colony and placing it in a drop of cotton blue (1g/L in lactic acid 88%), between slide and coverslip. Potentially toxigenic fungi were identified: Aspergillus sp., Rhizopus sp., Alternaria sp., Penicillium sp. and Fusarium sp. The presence of these fungi in peanut samples indicates the possibility of development of mycotoxins potentially toxic to humans. The roasting process may not be sufficient to destroy some mycotoxins.(AU)

Scorpions trapped in amber: a remarkable window on their evolution over time from the Mesozoic period to present days

This synoptic review aims to bring some general information on fossil scorpions, namely those trapped in amber - fossilized resin - ranging from Lower Cretaceous through the Palaeocene and up to the Miocene. The question to be addressed is how the study of these fossils can be connected with possible present scorpionism problems. A precise knowledge of these ancient lineages provides information about the evolution of extant lineages, including the buthoids, which contain most known noxious species. Among the Arthropods found trapped in amber, scorpions are considered rare. A limited number of elements have been described from the Late Tertiary Dominican and Mexican amber, while the most ancient Tertiary amber from the Baltic region produced more consistent results in the last 30 years, primarily focusing on a single limited lineage. Contrarily, the Cretaceous amber from Myanmar, also called Burmite, has yielded and continues to yield a significant number of results represented by several distinct lineages, which attest to the considerable degree of diversity that existed in the Burmese amber-producing forests. As in my previous similar contributions to this journal, the content of this note is primarily addressed to non-specialists whose research embraces scorpions in various fields such as venom toxins and public health. An overview knowledge of at least some fossil lineages can eventually help to clarify why some extant elements associated with the buthoids represent dangerous species while others are not noxious.(AU)

Scorpions trapped in amber: a remarkable window on their evolution over time from the Mesozoic period to present days

This synoptic review aims to bring some general information on fossil scorpions, namely those trapped in amber - fossilized resin - ranging from Lower Cretaceous through the Palaeocene and up to the Miocene. The question to be addressed is how the study of these fossils can be connected with possible present scorpionism problems. A precise knowledge of these ancient lineages provides information about the evolution of extant lineages, including the buthoids, which contain most known noxious species. Among the Arthropods found trapped in amber, scorpions are considered rare. A limited number of elements have been described from the Late Tertiary Dominican and Mexican amber, while the most ancient Tertiary amber from the Baltic region produced more consistent results in the last 30 years, primarily focusing on a single limited lineage. Contrarily, the Cretaceous amber from Myanmar, also called Burmite, has yielded and continues to yield a significant number of results represented by several distinct lineages, which attest to the considerable degree of diversity that existed in the Burmese amber-producing forests. As in my previous similar contributions to this journal, the content of this note is primarily addressed to non-specialists whose research embraces scorpions in various fields such as venom toxins and public health. An overview knowledge of at least some fossil lineages can eventually help to clarify why some extant elements associated with the buthoids represent dangerous species while others are not noxious.(AU)

Transcriptome analysis of the spider Phonotimpus pennimani reveals novel toxin transcripts

Background: Phonotimpus pennimani (Araneae, Phrurolithidae) is a small-sized (3-5 mm) spider endemic to the Tacaná volcano in Chiapas, Mexico, where it is found in soil litter of cloud forests and coffee plantations. Its venom composition has so far not been investigated, partly because it is not a species of medical significance. However, it does have an important impact on the arthropod populations of its natural habitat. Methods: Specimens were collected in Southeastern Mexico (Chiapas) and identified taxonomically by morphological characteristics. A partial sequence from the mitochondrial gene coxI was amplified. Sequencing on the Illumina platform of a transcriptome library constructed from 12 adult specimens revealed 25 toxin or toxinlike genes. Transcripts were validated (RT-qPCR) by assessing the differential expression of the toxin-like PpenTox1 transcript and normalising with housekeeping genes. Results: Analysis of the coxI-gene revealed a similarity to other species of the family Phrurolithidae. Transcriptome analysis also revealed similarity with venom components of species from the families Ctenidae, Lycosidae, and Sicariidae. Expression of the toxinlike PpenTox1 gene was different for each developmental stage (juvenile or adult) and also for both sexes (female or male). Additionally, a partial sequence was obtained for the toxin-like PpenTox1 from DNA. Conclusion: Data from the amplification of the mitochondrial coxI gene confirmed that P. pennimani belongs to the family Phrurolithidae. New genes and transcripts coding for venom components were identified.(AU)

Congenital extrahepatic portosystemic deviation of gastric vein with azygos in a bitch

Background: Portosystemic shunt (PSS), an alteration commonly found in toy dogs, is caused by an anastomosis between the systemic and portal circulation, interfering with the metabolism of several toxins. It can be of congenital or acquired origin and is classified as intra- or extrahepatic. Clinical signs include the gastrointestinal tract, nervous system, and urinary system according to the fraction of the shunt. It is diagnosed by several imaging tests and exploratory laparotomy. Therapy involves drug therapy and/or surgical correction of the anomalous vessels. Thus, the aim is to present an unusual case of extrahepatic cPSS originating from the left gastric vein and insertion into the azygos vein. Case: A 2-year-old female toy poodle, spayed, weighing 2.7 kg was treated with a history of recurrent cystitis and neurological signs such as focal seizures, ataxia, tremors, blindness, lethargy, head pressing, and compulsive gait. Complementary tests revealed normochromic microcytic anemia, neutrophilia-induced leukocytosis, monocytosis, and lymphopenia. Biochemical analysis revealed hypoproteinemia due to hypoglobulinemia, an increase in alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and gamma-glutamyl transferase, and a decrease in urea. In the urinalysis, ammonium biurate crystals were detected, and Doppler ultrasound revealed microhepathy and the presence of an anomalous gastrosplenic vein inserted into the azygos vein, a finding compatible with the congenital extrahepatic PSS. Abdominal tomography confirmed vascular deviation with a sinuous path originating from the left gastric and splenic veins, inserting into the azygos vein, measuring approximately 5.95 cm in length. Cranial tomography revealed changes consistent with hepatic encephalopathy. Drug therapy was performed with hydration, liver chow, lactulose, probiotics, metronidazole, S-adenosyl-L-methionine, and ursodeoxycholic acid, and after 15 days, surgery was performed to place a 3.5 mm ameroid constrictor ring for gradual occlusion of the anomalous vessel. The animal recovered well, and a control abdominal ultrasound was repeated 30 days after the procedure, noting that the constrictor had not yet fully occluded the deviation. Doppler imaging revealed a favorable evolution with an increase in the diameter of the portal vein in the hepatopetal direction. The patient was followed-up for a year and had a normal and healthy life. Discussion: Extrahepatic PSS is frequently diagnosed in purebred and toy dogs, commonly occurring between the portal vein and one of its tributaries, with a lower frequency of anomalous vessels between the azygos veins, as in the present report. The patient's age and clinical signs were compatible with the disease, in addition to ammonia biurate crystals and hematological and biochemical alterations. The neurological clinical signs observed were compatible with hepatic encephalopathy secondary to congenital PSS. The imaging examinations facilitated the identification of the extrahepatic vascular anomaly, with the tomography being more accurate and helping in proper surgical planning. Clinical treatment should be performed for presurgical stabilization, and occlusion can be performed by placing cellophane bands or an ameroid constrictor, which is the technique of choice for congenital PSS, as it allows for slow constriction to avoid acute portal hypertension, as in this case, emphasizing that anesthesia in animals with portosystemic shunts must be performed with care.

Comparative venomic profiles of three spiders of the genus Phoneutria

Abstract Background: Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.

Toxinology in the proteomics era: a review on arachnid venom proteomics

The word venomics was coined to acknowledge the studies that use omics to investigate venom proteins and peptides. Venomics has evolved considerably over the last 20 years. The first works on scorpion or spider venomics were published in the early 2000's. Such studies relied on peptide mass fingerprinting (PMF) to characterize venom complexity. After the introduction of new mass spectrometers with higher resolution, sensitivity and mass accuracy, and the next-generation nucleotide sequencing, the complexity of data reported in research on scorpion and spider venomics increased exponentially, which allowed more comprehensive studies. In the present review article, we covered key publications on scorpion venomics and spider venomics, presenting historical grounds and implemented technologies over the last years. The literature presented in this review was selected after searching the PubMed database using the terms "(scorpion venom) AND (proteome)" for scorpion venomics, and "(spider venom) AND (proteome)" for publications on spider venomics. We presented the key aspects related to proteomics in the covered papers including, but not restricted to, the employed proteomic strategy (i.e., PMF, two-dimensional gel electrophoresis, shotgun/bottom-up and/or top-down/peptidome), and the type of mass spectrometer used. Some conclusions can be drawn from the present study. For example, the scorpion genus Tityus is the most studied concerning venomics, followed by Centruroides; whereas for spiders the studied genera were found more equally distributed. Another interesting conclusion is the lack of high throughput studies on post-translational modifications (PTMs) of scorpion and spider proteins. In our opinion, PTMs should be more studied as they can modulate the activity of scorpion and spider toxins.(AU)

Comparative venomic profiles of three spiders of the genus Phoneutria

Spider venoms induce different physio-pharmacological effects by binding with high affinity on molecular targets, therefore being of biotechnological interest. Some of these toxins, acting on different types of ion channels, have been identified in the venom of spiders of the genus Phoneutria, mainly from P. nigriventer. In spite of the pharmaceutical potential demonstrated by P. nigriventer toxins, there is limited information on molecules from venoms of the same genus, as their toxins remain poorly characterized. Understanding this diversity and clarifying the differences in the mechanisms of action of spider toxins is of great importance for establishing their true biotechnological potential. This prompted us to compare three different venoms of the Phoneutria genus: P. nigriventer (Pn-V), P. eickstedtae (Pe-V) and P. pertyi (Pp-V). Methods: Biochemical and functional comparison of the venoms were carried out by SDS-PAGE, HPLC, mass spectrometry, enzymatic activities and electrophysiological assays (whole-cell patch clamp). Results: The employed approach revealed that all three venoms had an overall similarity in their components, with only minor differences. The presence of a high number of similar proteins was evident, particularly toxins in the mass range of ~6.0 kDa. Hyaluronidase and proteolytic activities were detected in all venoms, in addition to isoforms of the toxins Tx1 and Tx2-6. All Tx1 isoforms blocked Nav1.6 ion currents, with slight differences. Conclusion: Our findings showed that Pn-V, Pe-V and Pp-V are highly similar concerning protein composition and enzymatic activities, containing isoforms of the same toxins sharing high sequence homology, with minor modifications. However, these structural and functional variations are very important for venom diversity. In addition, our findings will contribute to the comprehension of the molecular diversity of the venoms of the other species from Phoneutria genus, exposing their biotechnological potential as a source for searching for new active molecules.(AU)

Antimicrobial resistance of Shiga toxin­producing Escherichia coliisolated from sheep / Escherichia coli produtora de toxina Shiga resistentes a antimicrobianos isoladas de ovinos

The presence of Shiga toxin-producing Escherichia coli (STEC) and resistance to beta-lactams in healthy sheep represents a potential public health risk. This study aimed to characterize STEC isolates in sheep feces for toxin production and resistance to beta-lactam antibiotics. In the present study, among the 40 isolates, we found a predominance of subtype Stx1 (22/40), followed by subtype Stx1 + Stx2 (11/40), while the less prevalent group was Stx2 (7/40). Also, we found phenotypical resistance to beta-lactam antibiotics in 50% (20/40) of the strains analyzed, forming two groups, one with resistant isolates and the other with non-resistant isolates. The cytotoxicity of the isolates did not vary among the groups. In addition to having this characteristic, some multiresistant isolates produced significant amounts of toxins. This leads to the conclusion that the mechanisms of antimicrobial resistance via beta-lactamases are present in sheep STEC and that the cytotoxicity of those isolates is variable regarding such resistance.(AU)

A presença de Escherichia coli produtora de toxina Shiga (STEC) e resistente a beta-lactâmicos em ovinos saudáveis, representa um risco potencial para a saúde pública. O objetivo deste estudo foi caracterizar isolados STEC presentes em fezes de ovinos, quanto a produção de toxina, bem como a resistência aos antibióticos beta-lactâmicos. No presente estudo, dentre os quarenta isolados, foi observada a predominância do subtipo Stx1 (22/40), seguido do subtipo Stx1+ Stx2 (11/40), enquanto o grupo menos prevalente foi Stx2 (7/40). A resistência fenotípica aos antibióticos beta-lactâmicos foi observada em 50% (20/40) das cepas analisadas, formando dois grupos, um com isolados resistentes e outro de isolados não resistentes. A citotoxicidade dos isolados não variou entre os grupos. Alguns isolados multirresistentes, além de possuírem essa característica, produziram quantidades significativas de toxinas. Isto conclui, que os mecanismos de resistencia antimicrobiana, por meio de beta-lactamases estão presentes em STEC de ovinos, e que a citotoxicidade desses isolados é variável com relação a esta resistência.(AU)

Effect of adsorbents on diets with corn contaminated by mycotoxins on the productive performance and health of broilers

A total of 1,296 broiler chicken were housed, distributed in a completely randomized design with 6 treatments and 6 repetitions. The treatments consisted of a control diet formulated with corn considered adequate and without the addition of adsorbent, a diet formulated with corn naturally contaminated with mycotoxin (CCM) and four diets formulated with CCM and added with different commercial adsorbents. At the end of the first week and at 21 days of age of the birds, it was observed that the control diet resulted in greater (p < 0.05) live weight and weight gain in relation to the inclusion of CCM. The relative weight of the liver was lower for the control group compared to the groups receiving a diet with CCM and CCM + ads D. The relative weight of the proventriculus and cloacal bursa was lower for the control group compared to those who received a diet with CCM + ads B and CCM+ ads C. There was no significant effect (p > 0.05) of the diets on the analysis of serum biochemistry and the occurrence of fatty and hydropic degeneration in the liver of broilers. The use of adsorbents can mitigate the harmful effects of mycotoxins, however, these products have specific binding capacity to the type of mycotoxin present in food.(AU)

Spodoptera frugiperda (Noctuidae) fed on transgenic maize can transfer Bt proteins to Podisus nigrispinus (Pentatomidae)

An important concern with the use of genetically modified (GM) plants expressing Bacillus thuringiensis (Bt) insecticidal toxins is the deleterious effect on non-target organisms. The predatory stink bug Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) is used in biological control programs and may be exposed to Bt toxins. This study evaluated the indirect effects of different Cry proteins on P. nigrispinus with the prey Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae), fed on simple or pyramided Bt maize genotypes. The experiment was carried out in a completely randomized design with three treatments: i) Isohybrid (not Bt), ii) Herculex® (transgenic maize encoding Cry1F protein) and iii) PowerCore® (pyramidal transgenic maize encoding the Cry1F, Cry1A.105, and Cry2Ab2 proteins), which were used to feed S. frugiperda for 48 h. The caterpillars were used as prey by P. nigrispinus females. We evaluated the presence of Cry proteins, consumed prey biomass (predation), oviposition period, number of postures, number of eggs, number of eggs per posture, number of nymphs, egg viability, embryonic period, female longevity and development, and survival rates of immature. The results show that different Cry proteins move through the food chain of P. nigrispinus and provide evidence that the ingestion of three different proteins does not lead to unexpected synergistic effects. However, Cry toxins promoted histopathological changes in midgut cells of P. nigrispinus.

Compositional and toxicological investigation of pooled venom from farm-raised Naja atra

Abstract Background: Naja atra is a venomous snake species medically relevant in China. In the current study, we evaluated the composition and toxicological profile of venom collected from farm-raised N. atra. Methods: Venom was collected from third-generation captive bred N. atra on a snake farm in Hunan Province, China. The venom was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis and nano-liquid chromatography with electrospray ionization tandem mass spectrometry. In addition, hemolytic activity, median lethal dose, serum biochemical and histopathological parameters were accessed. Results: N. atra venom proteome was dominated by phospholipase A2 (46.5%) and three-finger toxins (41.4 %), and a set of common low relative abundance proteins, including cysteine-rich secretory proteins (4.7%), NGF-beta (2.4%), snake venom metalloproteinase (1.5%), glutathione peroxidase (0.6%), vespryn (0.3%), and 5-nucleotidases (0.2%) were also found. Furthermore, the venom exhibited direct hemolytic activity, neurotoxicity, myotoxicity, and high lethal potency in mice, with a subcutaneous median lethal dose of 1.02 mg/kg. Histopathological analysis and serum biochemical tests revealed that venom caused acute hepatic, pulmonary and renal injury in mice. Conclusion: This study revealed the composition and toxicity of venom collected from farm-raised N. atra, thereby providing a reference for the analysis of venom samples collected from captive-born venomous snakes in the future.

Use of different adsorbents in broiler diets naturally contaminated by mycotoxins

This study investigated the effects of adding different adsorbent substances to broilers feed naturally contaminated by mycotoxins. Two hundred and eighty male 1-day-old chicks, Cobb Slow® lineage, were distributed in a randomized block design with 4 treatments, 5 repetitions with 14 birds each. The treatments consisted of: T1-basal feed naturally contaminated with mycotoxins. T2-basal feed + Bentonite, Thistle Extract, Yeast Extract, Vitamin E and Choline. T3-basal feed + Bentonite, Thistle Extract, yeast cell wall and Silymarin. T4-basal feed + Bentonite and Algae extract. Performance (weight gain, feed intake, feed conversion) at 7, 14, 21, 28 days were evaluated. At 28 days, a portion of the jejunum was collected in two birds by replicate to study the intestinal morphology. The relative weight of the gizzard, proventricle and total intestine was evaluated. The data obtained were analyzed using the statistical program SAS (9.3). With the use of any adsorbents studied, the performance and liver weight were improved in all evaluated periods. Thus, the inclusion of adsorbents improves the performance of the broiler chickens when the feed is contaminated by mycotoxins.(AU)

Type C botulism in dogs from rural properties located in Goiânia, Brazil

Botulism is a disease usually fatal, caused by the ingestion of neurotoxins produced by Clostridium botulinum. In dogs, intoxication is caused by the ingestion of botulinum toxin type C, and animals often recover spontaneously. The present study describes the occurrence of type C botulism in two dogs domiciled on neighboring rural properties in the municipality of Goiânia, state of Goiás, Brazil, probably associated with ingestion of decomposing bovine carcass. Upon clinical evaluation, the dogs were alert in the lateral decubitus position with ascending flaccid paralysis, absence of eyelid reflexes, and reduced muscle tone. Due to their worsening clinical symptoms, the animals died within 12 h and 3 days after supportive treatment. Botulinum toxin type C was identified, in the serum and feces of both dogs, by seroneutralization in mice with homologous monovalent antitoxin. The results of the high-throughput gene sequencing showed that the abundance of C. botulinum in the fecal microbiota of one of the affected dogs was low (0.53%). In this way, the present study highlights the need of sanitary practices related to the appropriate collection and disposal of bovine carcasses in rural areas since they represent a risk factor for the occurrence of botulism in dogs domiciled on rural properties.

Compositional and toxicological investigation of pooled venom from farm-raised Naja atra

Background: Naja atra is a venomous snake species medically relevant in China. In the current study, we evaluated the composition and toxicological profile of venom collected from farm-raised N. atra. Methods: Venom was collected from third-generation captive bred N. atra on a snake farm in Hunan Province, China. The venom was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis and nano-liquid chromatography with electrospray ionization tandem mass spectrometry. In addition, hemolytic activity, median lethal dose, serum biochemical and histopathological parameters were accessed. Results: N. atra venom proteome was dominated by phospholipase A2 (46.5%) and three-finger toxins (41.4 %), and a set of common low relative abundance proteins, including cysteine-rich secretory proteins (4.7%), NGF-beta (2.4%), snake venom metalloproteinase (1.5%), glutathione peroxidase (0.6%), vespryn (0.3%), and 5ʹ-nucleotidases (0.2%) were also found. Furthermore, the venom exhibited direct hemolytic activity, neurotoxicity, myotoxicity, and high lethal potency in mice, with a subcutaneous median lethal dose of 1.02 mg/kg. Histopathological analysis and serum biochemical tests revealed that venom caused acute hepatic, pulmonary and renal injury in mice. Conclusion: This study revealed the composition and toxicity of venom collected from farm-raised N. atra, thereby providing a reference for the analysis of venom samples collected from captive-born venomous snakes in the future.(AU)

Antimicrobial susceptibility of Salmonella spp and Staphylococcus aureus isolated from beef sold in Campo Grande, Mato Grosso do Sul, Brazil / Suscetibilidade antimicrobiana de Salmonella spp e Staphylococcus aureus isolados de carnes bovinas comercializadas em Campo Grande, Mato Grosso do Sul, Brasil

Hygiene failures in meat can be identified based on the evaluation of pathogenic microorganisms, which compromise the microbiological quality of food and can transmit food-borne diseases. The aim of the present study was to evaluate the hygienic quality of beef sold at supermarkets, butcher shops and public markets in the city of Campo Grande, state of Mato Grosso do Sul, Brazil, through the phenotypic and genotypic characterization of Salmonella spp. and Shiga toxin-producing Escherichia coli (STEC) as well as the investigation and quantification of Staphylococcus aureus. Seventy-one samples of beef from 17 commercial establishments were evaluated. Isolates were tested for antimicrobial susceptibility using the disk diffusion method recommended by the Clinical & Laboratory Standards Institute. Salmonella was found in 7.04% of the samples and 70.0% of the isolates were sensitive to the antimicrobials tested. A total of 25.35% of the samples were positive for Staphylococcus aureus, with counts ranging from 1.0 x 102 to 4.3 x 104 CFU/g; these isolates exhibited resistance to penicillin (87.5%), tetracycline (18.75%) and chloramphenicol (6.25%). None of the samples was positive for STEC. The detection of these pathogens in food poses a danger to public health, mainly due to the presence of antimicrobial-resistant isolates. These findings underscore the need for good hygiene and manufacturing practices at retail establishments.

As falhas na qualidade higiênico-sanitária da carne podem ser identificadas a partir da avaliação de microrganismos patogênicos que comprometem a qualidade microbiológica do alimento e podem veicular doenças de origem alimentar. O presente estudo objetivou avaliar a qualidade higiênica-sanitária de carnes bovinas comercializadas em supermercados, açougues e mercados públicos da cidade de Campo Grande (Mato Grosso do Sul, Brasil) por meio da pesquisa e caracterização fenotípica e genotípica de Salmonella spp. e Escherichia coli produtora de toxina Shiga (STEC) e pesquisa e contagem de Staphylococcus aureus. Foram avaliadas 71 amostras de carne bovina de 17 estabelecimentos comerciais que foram submetidas a pesquisa de detecção de Salmonella spp., Escherichia coli produtora de toxina Shiga (STEC) e pesquisa e contagem de Staphylococcus aureus. Os isolados obtidos foram submetidos ao perfil de sensibilidade aos antimicrobianos pelo teste de difusão em disco, de acordo com o Clinical & Laboratory Standards Institute (CLSI). Constatou-se a presença de Salmonella em 7,04% das amostras avaliadas, sendo que 70,0% dos isolados foram sensíveis aos antimicrobianos testados. Em relação ao Staphylococcus aureus, 25,35% das amostras foram positivas com contagens variando entre 1,0 x 102 a 4,3 x 104 UFC/g, sendo que os isolados apresentaram resistência para penicilina (62,5%), tetraciclina (18,75%) e cloranfenicol (6,25%). Nenhuma amostra apresentou-se positiva para STEC. A detecção desses patógenos em alimentos representa um perigo a saúde pública, principalmente, devido a presença de isolados resistentes a antimicrobianos. Além disso, ressalta-se a necessidade do emprego das boas práticas de higiene e fabricação nos estabelecimentos varejistas.

ß-micrustoxin (Mlx-9), a PLA2 from Micrurus lemniscatus snake venom: biochemical characterization and anti-proliferative effect mediated by p53

Background: Endogenous phospholipases A2 (PLA2 ) play a fundamental role in inflammation, neurodegenerative diseases, apoptosis and cellular senescence. Neurotoxins with PLA2 activity are found in snake venoms from the Elapidae and Viperidae families. The mechanism of action of these neurotoxins have been studied using hippocampal and cerebellar neuronal cultures showing [Ca2+]i increase, mitochondrial depolarization and cell death. Astrocytes are rarely used as a model, despite being modulators at the synapses and responsible for homeostasis and defense in the central nervous system. Preserving the cell division ability, they can be utilized to study the cell proliferation process. In the present work cultured astrocytes and glioblastoma cells were employed to characterize the action of ß-micrustoxin (previously named Mlx-9), a PLA2 isolated from Micrurus lemniscatus snake venom. The ß-micrustoxin structure was determined and the cell proliferation, cell cycle phases and the regulatory proteins p53, p21 and p27 were investigated. Methods: ß-micrustoxin was characterized biochemically by a proteomic approach. Astrocytes were obtained by dissociation of pineal glands from Wistar rats; glioblastoma tumor cells were purchased from ATCC and Sigma and cultured in DMEM médium. Cell viability was evaluated by MTT assay; cell proliferation and cell cycle phases were analyzed by flow cytometry; p53, p21 and p27 proteins were studied by western blotting and immunocytochemistry. Results: Proteomic analysis revealed fragments on ß-micrustoxin that aligned with a PLA2 from Micrurus lemniscatus lemniscatus previously identified as transcript ID DN112835_C3_g9_i1/m.9019. ß-micrustoxin impaired the viability of astrocytes and glioblastoma tumor cells. There was a reduction in cell proliferation, an increase in G2/M phase and activation of p53, p21 and p27 proteins in astrocytes. Conclusion: These findings indicate that ß-micrustoxin from Micrurus lemniscatus venom could inhibit cell proliferation through p53, p21 and p27 activation thus imposing cell cycle arrest at the checkpoint G2/M.(AU)

Deoxynivalenol biosynthesis and accumulation in wheat under application of carrageenan / Biossíntese e acúmulo de desoxinivalenolem trigo submetido à aplicação de carragena

Mycotoxins pose a large threat to human and livestock besides reducing the quality of food/feed.It is believed that these toxins are biosynthesized as a mechanism of defense (stress-response) of fungi. The most important mycotoxin for winter-cereal crops is known by deoxynivalenol (DON), a trichothecene biosynthesized mainly by Fusarium graminearum. This manuscript brings data of three years (2018, 2019 and 2020) of field research (24 fieldexperiments) in Western Santa Catarina and North-Western Rio Grande do Sul, Brazil using a sulphated polysaccharide exclusive from red seaweed, carrageenan, associated with fungicides to help suppressing deoxynivalenol (DON) biosynthesis and accumulation in wheat kernels. A reduction of 36.4% in DON contamination was observed. Weather conditions have influenced the accumulation of DON in wheat kernels. Carrageenan has shown to be a biological compound capable of helping on the suppression of DON biosynthesis and accumulation in wheat kernels regardless of weather conditions.(AU)

As micotoxinas representam uma grande ameaça para humanos e animais, além de reduzirem a qualidade de alimentos/rações. Acredita-se que essas toxinas sejam biossintetizadas como mecanismo de defesa (resposta ao estresse) de fungos. A micotoxina de maior interesse para cereais de inverno é conhecida por desoxinivalenol (DON), um tricoteceno biossintetizado principalmente por Fusariumgraminearum. Esse estudo traz dados de três anos (2018, 2019 e 2020) de pesquisa de campo (24 experimentos) conduzidos no Oeste de Santa Catarina e no Nordeste do Rio Grande do Sul, Brasil,utilizando um polissacarídeo sulfatado exclusivo de algas vermelhas, carragena, associado a fungicidas para ajudar na supressão da biossíntese e acúmulo de desoxinivalenol (DON) em grãos de trigo. Foi observada uma redução de 36,4% na contaminação por DON. As condições climáticas influenciaram no acúmulo de DON nos grãos de trigo. A carragena se demostrou como um composto biológico capaz de atenuar a biossíntese e acúmulo de DON em grãos de trigo independente das condições climáticas.(AU)