Comparison between different sources of minerals in horses with nutritional secondary hyperparathyroidism / [Comparação entre diferentes fontes de minerais em cavalos com hiperparatireoidismo secundário nutricional]

Minerals perform several functions in the body, such as coagulation actions, muscle contraction, enzymatic and hormonal production, among others. This study aims to evaluate the effect of a 150 days chelated and not chelated mineral supplementation with and without potassium oxalate on serological parameters and bone mineral density of horses. Twenty-four crossbred yearlings (12 females and 12 males) with an average age of 21±3 months and body weight of 330.8±37.9kg were divided into four groups containing six equines in each (three females and three males) in a completely randomized design with repeated measurements in a 2x2 factorial arrangement. Treatments were: 1 - chelated minerals compound; 2 - chelated minerals compound and potassium oxalate; 3 - not chelated minerals compound; and 4 - not chelated minerals compound and potassium oxalate. Clinical signs of nutritional secondary hyperparathyroidism (NSH) were observed only in treatment 4. Results showed no treatment effect in bone biopsy for calcium, phosphorus and bone density. There were significant reductions of parathyroid hormone (PTH) means concentrations in treatments 2 and 4 during supplementation. Animals supplemented with chelated minerals compounds avoided mineral imbalances and NSH even when in dietary potassium oxalate challenged.(AU)

Os minerais desempenham diversas funções no organismo, como ações de coagulação, contração muscular, produção enzimática e hormonal, entre outras. O objetivo deste estudo foi avaliar o efeito da suplementação de minerais quelatados e não quelatados, por 150 dias, com e sem oxalato de potássio, sobre parâmetros sorológicos e densidade mineral óssea em equinos. Vinte e quatro filhotes mestiços (12 fêmeas e 12 machos), com idade média de 21±3 meses e peso corporal de 330,8±37,9kg, foram divididos em quatro grupos contendo seis equinos cada (três fêmeas e três machos), em delineamento inteiramente ao acaso, com repetição medida em arranjo fatorial 2x2. Os tratamentos foram: 1 - composto mineral quelatado; 2 - composto mineral quelatado e oxalato de potássio; 3 - composto mineral não quelatado; e 4 - composto mineral não quelatado e oxalato de potássio. Os sinais clínicos do hiperparatireoidismo secundário nutricional (NSH) foram observados apenas no tratamento 4. Os resultados não mostraram efeito de tratamento na biópsia óssea para cálcio, fósforo e densidade óssea. Houve redução significativa do hormônio da paratireoide (PTH) em concentrações médias nos tratamentos 2 e 4 durante a suplementação. Os animais suplementados com compostos minerais quelatados evitaram desequilíbrios minerais e NSH, mesmo quando desafiados no oxalato de potássio na dieta.(AU)

Micotoxinas e adsorventes na alimentação animal / Mycotoxins and adsorbents in animal feed

As micotoxinas são substâncias produzidas durante o processo metabólico de alguns fungos, elas são extremamente nocivas aos animais. Esses fungos estão presentes em diversos tipos de cereais e frutas. O milho, principal cereal utilizado na alimentação animal, pode ser acometido por fungos dos gêneros Aspergillus e Fusarium, que quando submetidos à umidade e temperaturas específicas produzem aflatoxinas, ocratoxina, fumonisinas e zearalenona que causam problemas no desempenho e produção dos animais. Os animais monogástricos, como aves e suínos, e de ceco funcional, como os equinos, são mais susceptíveis aos efeitos que essas substâncias podem causar, quando comparados aos animais ruminantes, pois estes apresentam no rúmen microrganismos que são capazes de digerir as micotoxinas. No entanto, animais como vacas leiteiras de alta produção e animais monogástricos, quando consomem alimentos contaminados durante um longo período, podem desenvolver problemas digestivos, neurológicos, queda na produção e até mesmo chegar a óbito. Diante disso, algumas técnicas vêm sendo utilizadas pelos produtores e fábricas de ração, visando o não fornecimento de grãos contaminados aos animais, como um controle de qualidade dos alimentos e o uso de adsorventes. Os adsorventes são aditivos adicionados à dieta dos animais com o objetivo de inativar as micotoxinas. Eles podem ser de origem orgânica, como as leveduras, ou inorgânicos derivados de argila. Esses aditivos se ligam à substância impedindo que estas sejam absorvidas pelo enterócito e, assim, sejam excretadas sem causar prejuízos ao metabolismo dos animais.

Mycotoxins are substances produced during the metabolic process of some fungi, they are extremely harmful to animals. These fungi are present in several types of cereals and fruits. The main cereal corn used in animal feed can be affected by fungi of the genera Aspergillus and Fusarium that when subjected to humidity and specific specifications such as aflotoxins, ochratoxin, fumonisins and zearalenone that cause problems in the performance and production of animals. Monogastric animals, such as poultry, pigs and functional dry animals such as horses, are more susceptible to the effects that these occurrences can cause, when compared to ruminant animals, as they present in the rumen, microorganisms that are capable of digesting as mycotoxins. However, animals such as high production dairy cows and monogastric animals, when consuming contaminated food for a long period can develop digestive, neurological problems, drop in production and even die. In view of this, some techniques have been used by producers and feed factories, adding the non supply of contaminated grains to animals, such as food quality control and the use of adsorbents. Adsorbents are suitable additives to the animals' diet in order to inactivate as mycotoxins. They can be of organic origin, like yeasts or inorganic derived from clay. These additives bind to a substance preventing them from being absorbed by the enterocyte, thus being excreted without causing damage to the animals' metabolism.

Synthesis and antimicrobial evaluation of two peptide LyeTx I derivatives modified with the chelating agent HYNIC for radiolabeling with technetium-99m

Background Current diagnostic methods and imaging techniques are not able to differentiate septic and aseptic inflammation. Thus, reliable methods are sought to provide this distinction and scintigraphic imaging is an interesting option, since it is based on physiological changes. In this context, radiolabeled antimicrobial peptides have been investigated as they accumulate in infectious sites instead of aseptic inflammation. The peptide LyeTx I, from the venom of Lycosa erythrognatha, has potent antimicrobial activity. Therefore, this study aimed to synthesize LyeTx I derivatives with the chelating compound HYNIC, to evaluate their antimicrobial activity and to radiolabel them with 99mTc. Methods Two LyeTx I derivatives, HYNIC-LyeTx I (N-terminal modification) and LyeTx I-K-HYNIC (C-terminal modification), were synthesized by Fmoc strategy and purified by RP-HPLC. The purified products were assessed by RP-HPLC and MALDI-ToF-MS analysis. Microbiological assays were performed against S. aureus (ATCC® 6538) and E. coli (ATCC® 10536) in liquid medium to calculate the MIC. The radiolabeling procedure of LyeTx I-K-HYNIC with 99mTc was performed in the presence of co-ligands (tricine and EDDA) and reducing agent (SnCl2. 2H2O), and standardized taking into account the amount of peptide, reducing agent, pH and heating. Radiochemical purity analysis was performed by thin-layer chromatography on silica gel strips and the radiolabeled compound was assessed by RP-HPLC and radioactivity measurement of the collected fractions. Data were analyzed by ANOVA, followed by Tukey test (p-values < 0.05). Results Both LyeTx I derivatives were suitably synthesized and purified, as shown by RP-HPLC and MALDI-ToF-MS analysis. The microbiological test showed that HYNIC-LyeTx I (N-terminal modification) did not inhibit bacterial growth, whereas LyeTx I-K-HYNIC (C-terminal modification) showed a MIC of 5.05 μmol.L−1 (S. aureus) and 10.10 μmol.L−1 (E. coli). Thus, only the latter was radiolabeled with 99mTc. The radiochemical purity analysis of LyeTx I-K-HYNIC-99mTc showed that the optimal radiolabeling conditions (10 μg of LyeTx I-K-HYNIC; 250 μg of SnCl2. 2H2O; pH = 7; heating for 15 min) yielded a radiochemical purity of 87 ± 1 % (n= 3). However, RP-HPLC data suggested 99mTc transchelation from LyeTx I-K-HYNIC to the co-ligands (tricine and EDDA). Conclusions The binding of HYNIC to the N-terminal portion of LyeTx I seems to affect its activity against bacteria. Nevertheless, the radiolabeling of the C-terminal derivative, LyeTx I-K-HYNIC, must be better investigated to optimize the radiolabeled compound, in order to use it as a specific imaging agent to distinguish septic and aseptic inflammation.(AU)

Exposure of free-living jaguars to Toxoplasma gondii, Neospora caninum and Sarcocystis neurona in the Brazilian Pantanal / Exposição de onças-pintadas a Toxoplasma gondii, Neospora caninum e Sarcocystis neurona no Pantanal brasileiro

Toxoplasma gondii, Neospora caninum and Sarcocystis neurona are related apicomplexan parasites that cause reproductive and neurological disorders in a wide range of domestic and wild animals. In the present study, the immunofluorescence antibody test (IFAT) was used to investigate the presence of antibodies against T. gondii, N. caninum and S. neurona in the sera of 11 free-living jaguars (Panthera onca) in two protected areas in the Pantanal region of Mato Grosso state, Brazil. Ten jaguars (90.9%) showed seropositivity for T. gondii, eight (72.7%) for S. neurona, and seven (63.6%) for N. caninum antigens. Our findings reveal exposure of jaguars to these related coccidian parasites and circulation of these pathogens in this wild ecosystem. To the best of our knowledge, this is the first serological detection of N. caninum and S. neurona in free-living jaguars.

Toxoplasma gondii, Neospora caninum e Sarcocystis neurona são coccídios relacionados responsáveis por causar desordens reprodutivas e neurológicas em uma ampla variedade de animais domésticos e selvagens. No presente estudo, a Reação de Imunofluorescência Indireta (RIFI) foi utilizada para investigar a presença de anticorpos contra T. gondii, N. caninum e S.neurona em soros de 11 onças-pintadas de vida livre (Panthera onca), provenientes de duas áreas protegidas na região do Pantanal do Estado de Mato Grosso, Brasil. Dez (90,9%), sete (63,6%) e oito (72,7%) onças amostradas foram soropositivas para T. gondii, N. caninum e S. neurona, respectivamente. Os resultados indicam a exposição a esses coccídios relacionados entre as onças-pintadas e a circulação ambiental desses patógenos nesse ecossistema selvagem. Este é o primeiro relato da detecção sorológica de N. caninum e S. neurona em onças-pintadas de vida livre.