Extract of Mangifera indica L. leaves may reduce biofilms of Staphylococcus spp. in stainless steel and teatcup rubbers.

Human ingestion of antimicrobial residues in dairy products is a problem of public health. In this study we evaluated antibacterial effectiveness of aqueous and ethanolic leaf extracts of Mangifera indica L. as a natural alternative for reduction of Staphylococcus spp. biofilms. Eight Staphylococcus spp. strains from cows with mastitis and the Staphylococcus aureus strain (ATCC 25923) were evaluated. High performance liquid chromatography indicated the presence of phenolic compounds in the aqueous extract. Agilent Technologies gas chromatography revealed the presence of phenolic compounds, carbohydrates, and gallic acid in ethanolic extract. The tannin contents were 2.27 ± 0.01 and 2.67 ± 0.01% for ethanolic extract and aqueous extract, respectively. Extracts were evaluated in agar diffusion test and the size of inhibition zones were compared. The ethanolic extract was the most effective, showing minimum inhibitory concentrations and minimum bactericidal concentrations between 1.8-7.5 and 15.1-45.3 mg/ml, respectively. After tannin removal, the extracts were less effective, indicating these secondary metabolites as one of the main antibacterial compounds. The ethanolic extract at 45.3 mg/ml reduced mature biofilms in teat rubber (average: 3.91 log reduction) and stainless steel (average: 3.87 log reduction) after 5 min of contact. The extracts of M. indica leaves represent natural alternatives against Staphylococcus spp. strains and the ethanolic extract shows potential as a natural sanitizer.

Plants of the Cerrado with antimicrobial effects against Staphylococcus spp. and Escherichia coli from cattle.

BACKGROUND: Both diarrhea in calves and mastitis in cows limit cattle production. The bacteria involved in these diseases have shown multi-resistance to antimicrobials, however plant metabolites therefore can provide an alternative method of control. This study selected and characterized Cerrado plant extracts showing inhibitory effects against Escherichia coli and Staphylococcus spp. from cattle. Thirteen leaf extracts were initially screened and diameters of inhibition zones produced against the pathogens were recorded using an agar disk diffusion method. Total condensed tannin contents were determined and antibacterial activities were analyzed after tannin removal from the five selected extracts. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were evaluated by macro-dilution antimicrobial susceptibility tests, and the extracts were characterized by high performance liquid chromatography. RESULTS: Inter- and intra-specific bacterial variations in the susceptibility to the extracts were detected. The aqueous extract (AE) from Caryocar brasiliense Cambess. leaves produced larger inhibition zones against E. coli strains than did other selected extracts. However, the AE from Schinopsis brasiliensis was the most effective against Staphylococcus spp. strains (P < 0.001). The MIC of ethanolic extracts (EE) from C. brasiliense (0.27 mg/mL) and S. brasiliensis (0.17 mg/mL) were lower than those of other extracts. The MIC and MBC of the Annona crassiflora EE were 6.24 mg/mL for all bacteria. Flavonoids were the main metabolites detected in the A. crassiflora EE as well as in the AE and EE from C. brasiliense, while tannins were the main metabolites in the S. brasiliensis leaf extracts. CONCLUSION: The AE from C. brasiliense was more effective against Gram-negative bacteria, while the AE from S. brasiliensis was more effective against Gram-positive bacteria. A. crassiflora EE and S. brasiliensis extracts are potent bactericide. After removal of the tannins, no antimicrobial effects were observed, indicating that these metabolites are the main active antibacterial components.

Perfil sanguíneo e peso de órgãos internos de bezerros leiteiros criados em diferentes sistemas de aleitamento / Blood profile and weight of internal organs of dairy calves in different nursing systems

Objetivou-se avaliar o perfil sanguíneo e o tamanho absoluto e relativo dos órgãos internos de bezerros em sistema de aleitamento convencional ou fracionado. Foram utilizadas 10 fêmeas, com peso corporal inicial médio de 37,53 kg (±2,36) e 12 machos com peso corporal médio de 81,6 kg (±8,6), ambos da raça Holandesa. O aleitamento convencional constituiu-se de quatro litros de leite fornecidos diariamente durante 54 dias de avaliação e o fracionado, de seis litros do 6º ao 25º dias de idade, quatro litros do 26º ao 45º dias de idade e dois litros do 46º ao 59º dias de idade, além de concentrado, feno de Cynodon sp., água e suplemento mineral fornecidos ad libitum. O delineamento experimental foi inteiramente ao acaso, com cinco repetições para os parâmetros sanguíneos e seis repetições para o desenvolvimento dos órgãos internos. As coletas de sangue foram realizadas nas fêmeas nos dias sete, 21, 28, 42, 49 e 56 de idade. Para a avaliação dos órgãos internos os machos foram abatidos aos dois meses de idade, após jejum de 16 horas. Não foram observadas diferenças para os valores de proteínas totais, albumina, globulina, creatinina, ureia, colesterol e β-hidroxibutirato nas idades avaliadas (p>0,05). Entretanto, para a concentração de glicose houve interação entre os sistemas de aleitamento e os períodos avaliados, podendo ser observado que com 21 dias de idade a concentração foi maior nas bezerras mantidas em sistema fracionado, quando comparadas aos animais do grupo convencional. O sistema de aleitamento não alterou o peso corporal final, peso corporal final vazio e o peso dos órgãos internos, exceto para o coração, demonstrando que o sistema de aleitamento fracionado não altera as avaliações dos órgãos internos...

The objective was to evaluate the blood profile together with the relative and absolute size of the internal organs of calves in conventional or fractionated feeding system. Ten females were used, with an average initial body weight of 37.53 kg (±2.36), and 12 males with a mean body weight of 81.6 kg (±8.6), both Holstein breed. The conventional feeding consisted of four liter milk supplied daily for 54 days of evaluation, and fractioned six liter milk was given from 6 to 25 days of age, four liter from 26 to 45 days of ager, and two liter from 46 to 59 days of age. Cynodon sp. hay, water and mineral supplement was provided ad libitum. The experimental design was completely randomized with five replicates for blood parameters and six replicates for the development of internal organs. Blood collections were performed in females on days seven, 21, 28, 42, 49 and 56 of age. For the evaluation of internal organs males were slaughtered at two months of age, after 16 hours of fasting. No differences occurred in the values of total protein, albumin, globulin, creatinine, urea, cholesterol and β-hydroxybutyrate in ages evaluated (p>0.05). However, for the concentration of glucose no interaction was found between lactation systems and periods evaluated. It can be noted that at 21 days of age the concentration was higher in calves kept in the fractionated system, when compared with animals of the conventional group. The feeding system did not affect the final body weight, the empty body weight or the weight of the internal organs, except for the heart, demonstrating that the fractional feeding system does not alter the assessment of the internal organs...

Effect of ethanolic extract of Capsicum frutescens L. on adult female of Rhipicephalus microplus (Ixodidae).

This study evaluated the effects of ethanol extract of Capsicum frutescens L. (Solanaceae), colloquially known as malagueta pepper, on egg production and hatching rate of larvae of Rhipicephalus microplus. Plant samples were collected in Montes Claros, Minas Gerais, Brazil. Selected mature fruits were washed, dehydrated in a forced air oven at 40 ± 5 °C to constant weight. The material was incubated in absolute ethanol during 10 days, and the extract was filtered, dried, and stored in amber vials under refrigeration at 4 °C. Engorged adult female ticks were immersed in 10 ml solutions of ethanol extracts at 25, 50, 75, 100, or 150 mg ml(-1) dry matter, solubilized in dimethyl sulfoxide (DMSO) at 1% v/v. These concentrations were compared to distilled water or 1% v/v DMSO in distilled water as negative controls and a commercial product as positive control. The extract resulted in significantly lower oviposition at all tested concentrations when compared to the negative controls. On days 2 and 3 posttreatment, mortality rates of female ticks ≥55% were observed for concentrations ≥75 mg ml(-1). These concentrations resulted in a significantly lower hatchability mean, and the LC90 on hatching inhibition of R. microplus, estimated by probit analysis, was 91.8 mg ml(-1). High acaricidal in vitro effect was verified, and toxicological tests and analyses in vivo are important to determine appropriate dosages and frequency of the application necessary to promote this extract as safe and effective alternative for control of R. microplus.

Desenvolvimento do trato digestivo de bezerros leiteiros criados em sistema de aleitamento fracionado / Development of the digestive tract of dairy calves reared in a fractionated nursing system

To evaluate the effect of the fractionated nursing system in rumen development were used 12 Holstein calves, with an initial body weight average of 37.0 kg, individually maintained in holding pens. Conventional treatment was made with four liters of milk daily, during 60 days and fractionated nursing was composed by six liters from the 6th until 25th day, four liters of 26 to 45 and two liters from 46 to 59 days of life. Besides that liquid diet, Cynodon sp. hay, water and mineral supplement were freely offered. Food consumption was monitored daily. The animals were weighted weekly at morning, after the delivery of liquid diet. At 60 days, the calves were euthanized and the digestive system was weighted and rumen papillae were microscopically measured. The nursing system did not interfere significantly in concentrate, hay and total dry matter intake. In contrast, fractionated nursing resulted in higher body weight at 60 days and significant increase in absolute weight of digestive tract, rumen-reticulum, omasum and intestines, so as relative weight of omasum, intestines and mitotic index of ruminal papillae. The fractionated nursing system may be a feeding alternative to improve the rumen development and of calves.

Para avaliar o efeito do sistema de aleitamento fracionado no desenvolvimento ruminal de bezerros leiteiros holandeses, foram utilizados 12 animais, com peso corporal inicial médio de 37,0 kg, alojados individualmente em baias. O tratamento convencional constituiu-se de quatro litros de leite diários durante 60 dias e o fracionado, de seis litros do 6º ao 25º dia; quatro litros dos dias 26 a 45 e dois litros de 46 a 59 dias de vida, além de concentrado, feno de Cynodon sp., água e suplemento mineral, oferecidos livremente. O consumo dos alimentos foi monitorado diariamente e os animais, pesados semanalmente, após o fornecimento da dieta líquida, pela manhã. Aos 60 dias de vida, os animais foram abatidos e realizaram-se pesagens do trato digestivo e medidas histológicas das papilas ruminais. O sistema de aleitamento não interferiu significativamente no consumo de concentrado, de feno, de matéria seca total e no peso corporal final vazio. O aleitamento fracionado resultou em maior peso corporal final, pesos absolutos do trato digestivo, do ruminorretículo, do omaso e dos intestinos, de pesos relativos do omaso e dos intestinos e maior índice mitótico das papilas ruminais. O sistema de aleitamento fracionado pode ser alternativa para melhorar o desenvolvimento ruminal e o desempenho de bezerros.

Efficacy of extracts of immature mango on ovine gastrointestinal nematodes.

The principal health problem in small ruminants is helminthiasis and the rapid development of nematode resistance to anthelminthics has limited the success of control in several countries, stimulating the search for alternatives. In this study, extracts of immature fruits of the mango Mangifera indica L. var Ubá were evaluated for inhibition of larval development and fecal egg count reduction in sheep naturally infected with gastrointestinal nematodes. In the phytochemical analyses, tannins and flavonoids were the metabolites identified. Aqueous extracts of immature fruits at 100 mg ml(-1) showed 100 % inhibition of larval development. The LC(90) of the extract was 35.9 mg ml(-1) and the in vivo anthelminthic efficacy at 0.740 g kg(-1) (BW, orally) was 53 %. The identification of larvae showed that 99.8 % were Haemonchus spp. In vitro and in vivo results indicate that this fruit could assist ovine nematode control.

In vitro and in vivo efficacy of aqueous extract of Caryocar brasiliense Camb. to control gastrointestinal nematodes in sheep.

A major problem faced in sheep rearing has been the rapid acquisition of anthelminthic-resistant populations of gastrointestinal nematodes. In the search for alternatives, aqueous extract of the peel of Caryocar brasiliense was evaluated for larval development inhibition, egg-hatching inhibition, and fecal nematode egg count reduction in sheep. For in vivo analysis, the doses were calculated according to a 10% lethal dose derived from acute toxicity tests in mice, and the efficacy was evaluated for two periods following oral administration of the extract. Egg-hatching inhibition at concentrations of 15 and 7.5 mg/ml was significantly higher than observed in negative controls with distilled water. For larval development inhibition, all concentrations showed anthelminthic activity significantly higher than controls and were not significantly different from ivermectin treatment. The LC(90) of larval development inhibition was 53.19 mg/ml. In vivo analysis for first and second weeks after treatment found 32.2% and 33% anthelminthic efficacy, respectively.