22 research outputs found

    O vulcanismo alta-sílica da região do Tupanci, NW do Escudo Sul-Rio-Grandense: faciologia, petrografia e litoquímica

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    Volcanic and hypabyssal acid rocks occur in the Tupanci area, NW portion of the Sul-Rio-Grandense Shield. These rocks are stratigraphically correlated to the Acampamento Velho Formation (~550 Ma), at the Camaquã Basin. This region has the northernmost exposure of this volcanic episode, which comprises effusive/ hypabyssal and pyroclastic rocks, with dominantly acid composition and sodic-alkaline affinity, whose genetic processes are linked to the post-collisional stages of the Brasiliano/Pan-Africano orogenic cycle. Acid volcanic rocks occur mainly as effusive deposits and also as pyroclastic deposits, in two Cerros (Hills): Tupanci and Picados. Cerro Tupanci defines an elongated (N-S) sub-volcanic intrusion of porphyritic rhyolites with phenocrysts of alkali feldspar and quartz surrounded by equigranular-fine-grained to aphanitic quartz-feldspar matrix, with a strong flow foliation on border regions. Cerro dos Picados shows texturally similar rhyolites, but with aphanitic to glassy matrix and presence of biotite; and pyroclastic deposits, characterized by rhyolitic ignimbrites. Ignimbrites occur in two facies: lithic-rich, with few devitrified and poorly elongated pumice and crystal fragments; and rheomorphic, with abundance of devitrified pumices with detachable eutaxitic texture, crystal fragments and rarely lithic fragments. Geochemical behavior allows to classify the magmatism as silica oversaturated, similar to the systems with high-silica, alkaline affinity and a metaluminous to slightly peralkaline trend with similar characteristics to “A” type granites. Petrographic and lithochemical data indicate a genetic linkage with the Acampamento Velho Formation magmatismA região do Tupanci, noroeste do Escudo Sul-Rio-Grandense (ESRG), apresenta depósi- tos vulcânicos ácidos, estratigraficamente correlacionados à Formação Acampamento Velho (~550 Ma), da Bacia do Camaquã.  Esta região é a exposição mais setentrional deste episódio vulcânico, caracterizado por sequências efusivas e piroclásticas, dominantemente ácidas, afinidade alcalina alta sílica sódica e vinculadas ao magmatismo pós-colisional do ciclo orogênico Brasiliano/Pan- -Africano no ESRG. As vulcânicas ácidas ocorrem na forma de depósitos efusivos e, em menor volu- me, piroclásticos, distribuídas em dois cerros: Cerro Tupanci e Cerro dos Picados. O Cerro Tupanci é uma intrusão subvulcânica alongada N-S, representada por riolitos porfiríticos, com fenocristais de sanidina e quartzo e uma matriz quartzo-feldspática equigranular fina a afanítica, com intensa foliação de fluxo nas regiões de borda. No Cerro dos Picados ocorrem riolitos texturalmente se- melhantes, porém com matriz afanítica de aspecto vítreo e presença de biotita, além de depósitos piroclásticos de ignimbritos riolíticos, divididos em duas fácies: uma rica em líticos, com púmices devitrificados e pouco estirados, além de pequenos e raros cristaloclastos; e outra de ignimbritos reomórficos, com abundantes púmices devitrificados, destacada textura eutaxítica, mais rica em cristaloclastos e raros litoclastos. O comportamento geoquímico de ambas as fácies classifica o magmatismo como supersaturado em sílica, semelhante aos sistemas de alta sílica, afinidade alcali- na sódica, e tendência metaluminosa a levemente peralcalina, com características dos granitos tipo “A”. Os dados faciológicos, petrográficos e litoquímicos obtidos indicam vinculação genética destas rochas com o vulcanismo da Formação Acampamento Velho.

    A SOMATOTROFINA BOVINA (bST) E SUA RELAÇÃO COM O RECRUTAMENTO FOLICULAR OVARIANO DURANTE O CICLO ESTRAL DE VACAS

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    O objetivo do experimento foi testar os efeitos da somatotrofina bovina (BST) no recrutamento de folículos ovarianos, durante o ciclo estral de vacas. Foram utilizadas seis vacas não lactantes Bostrurus taurus antes do experimento, os animais foram submetidos a exames ginecológicos completos, estando o escore médio da condição corporal dos animais em 3,0. As vacas foram divididas ao acaso em dois grupos: G1 - três animais, tratados com somatotrofina bovina recombinante (BST) 500 mg, de liberação lenta com vitamina E (IM); G2 - três vacas controles, que receberam 10 ml (IM) de solução fisiológica estéril como placebo. Para sincronizar o estro base das vacas foram utilizados implantes de norgestomet de 3 mg, na face externa da orelha (SC). O implante permaneceu por 10 dias seguidos nos animais de ambos os grupos e na sua retirada, utilizou-se uma dose de 500 ì g de cloprostenol (IM). No 3º dia pós estro os animais foram tratados respectivamente com BST (G1) e solução fisiológica para os controles (G2). Diariamente, a partir do dia do estro base até o próximo estro, os ovários das vacas foram monitorados¨ ultrassonograficamente com vistas ao número de folículos recrutados em cada onda folicular, verificação do folículo dominante (FD) e sua evolução, bem como o diâmetro individual dos outros folículos. Para o monitoramento folicular ovariano, foi utilizado aparelho de ultrassonografia e transdutor linear de 5.0 megahertz. Foram detectados durante o ciclo estral em média 8,5 e 8,3 folículos maiores que 4,0 mm de diâmetro nos animais dos G1 e G2 respectivamente; em torno do 10º dia pós tratamento observou-se o maior número de folículos recrutados em ambos os grupos; houve cinco animais com 2 ondas foliculares e um com três, sendo o número de folículos recrutados em cada onda como segue (G1 e G2, respectivamente): 1ª onda 7,6 e 7,0; 2ª onda 8,3 e 8,0; dia da detecção do 1º FD 1,0 e 1,6 dias ; 2º FD 8,6 e 9,0 dias; duração da 1ª onda folicular 11,6 e 9,6 dias; da 2ª onda folicular 8,0 e 7,6 dias; diâmetro máximo do 1º FD 18,2 e 15,8 mm; do 2º FD 16,6 e 15,0 mm; diâmetro do corpo lúteo (CL) do estro base 30,7 e 24,3 mm; dia do diâmetro folicular máximo pós tratamento do FD da 1ª onda: 8,6º e 10,3º; do 2º FD 18,6º e 16,6º dia. Baseados nesses resultados concluiu-se que a aplicação isolada de BST no 3º dia do ciclo estral, não exerceu influência entre os grupos relativamente ao recrutamento folicular ovariano, à exceção da duração da fase luteal, a qual alongou-se significativamente (p0,05) entre os grupos. A administração do BST expressou uma tendência em maior número de folículos recrutados (p>0,05). The bovine somatotrophin in the estrus cycle and its relationships with the ovarian follicular recruitment in cows Abstract The aim of this research was to evaluate the effects of the bovine somatotropin (BST) on the ovarian follicular wave of estrus cycle in cows. Six nonlactating cows Bos taurus taurus, from which four Holstein Friesian, one Jersey and one Holstein-pingzgauer breed, were used. The cows were submitted to a genital examination prior to the experiment, the mean body score condition observed being 3.0. The animals were maintained on oat and azeven pasture, with corn silage and mineral suplementation ad libitum. The cows were ramdomly divided in two groups: G1 three animals treated with 500 mg BST in the third day post estrus; G2 - three control cows (10 ml physiologic solution). Norgestomet implants on the ear internal face and intramuscular PGF2 alpha were used to perform the estrus synchronization. The bovine ovaries were daily scanned by ultrasound, from the estrus day to the following estrus, in order to detect the follicular development in each follicular wave. During the estrus cycle 8.5 and 8.3 follicles bigger than 4.0 mm of diameter were detected in G1 and G2, respectively. The highest number of recruitment follicles occurred in both groups around the 10th day post treatment; five cows had two follicular waves and the other, one. The number of recruitment follicles in each wave for G1 and G2 group was respectively: 1st wave, 7.6 and 7.0; 2nd wave, 8.3 and 8.0; 1st dominant follicle (FD) detection 1.0 and 1.6 days; 2nd FD detection 8.6 and 9.0 days; 1st follicular wave length, 11.6 and 9.6 days; 2nd follicular wave, 8.0 and 7.6 days. The maximum diameter of the 1st FD was 18.2 and 15.8 mm; from the 2nd FD 16.6 and 15.0 mm; CL diameter from the estrus basis, 30.7 and 24.3 mm; at the day of the major follicular diameter post treatment of the 1st FD (1st wave) 8.6 and 10.3; from the 2nd wave, FD 18.6 and 16.6 day, respectively. In conclusion, the isolated administration of BST in the 3rd day of the estrus cycle did not influence the follicular recruitment between groups, except on the length of the luteal phase (p0.05) between groups. The BST effect appointed a tendency on the greater number of recruitment follicles (p>0,05)

    Supplementation with green tea and oregano extracts on productive characteristics, blood metabolites, and antioxidant status of Jersey cows during the transition period.

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    Plant extracts have been recognized as beneficial to human health and have been evaluated as feed additive for domestic and companion animals. This study evaluated oregano and green tea extracts fed to Jersey cows from approximately 21 d before calving to 21 d after calving on milk production, milk composition, and blood metabolites as well as investigated immunological and antioxidant attributes. Twenty-four Jersey cows with 441 ± 27 kg of BW, 3.5 ± 0.3 of body condition score (BCS), and 2.7 ± 1.8 lactations were selected at approximately 28 d before the expected parturition date and were randomly assigned to three treatments with eight cows each: without plant extracts in diet (control ? CON), addition of 10 g per day of oregano extract (OR), and addition of 5 g per day of green tea extract (GT). Feed intake, BW, BCS, blood metabolites, hemogram as well as oxidative stress biomarkers were evaluated from approximately 3 weeks prepartum to 3 weeks postpartum (transition period) while milk production and composition were evaluated during the first 3 weeks of lactation. Plant extracts did not change BW, BCS, and DM intake (DMI) throughout the transition period, but OR increased in approximately 20% total digestive nutrients and metabolizable energy intake on days 15 and 16 postpartum compared with CON. In the prepartum, OR increased in 48% platelets count compared to the CON, while GT augmented in 142% eosinophils compared with CON. Oregano extract reduced the levels of reactive species in the erythrocytes in 40% during prepartum and postpartum compared with CON, while GT reduced its levels in 24 and 29% during prepartum and postpartum, respectively, when compared with CON. In the postpartum period, OR increased in 60% the carbonylated protein content compared with CON, while GT reduced in 45% the levels of reactive species in plasma compared with CON. During the postpartum, both extracts increased in 33% the concentration of reduced glutathione when compared with CON. Moreover, GT tended to decrease feed efficiency in 11% when compared with CON; OE reduced milk pH and somatic cell count when compared with CON. In conclusion, OE and GT did not expressively affect immunological attributes in blood but reduce some oxidative stress biomarkers without compromising productive traits of Jersey cows during the transition period

    Calves fed with milk from cows receiving plant extracts improved redox status.

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    The objective of this study was to evaluate the biomarkers of the redox state of pre-weaned Jersey dairy calves that consumed milk from cows supplemented with green tea (Camellia sinensis) or oregano extracts (Origanum vulgare). A completely randomized design was used with repeated measures in time. From their birth to 60 days of life, 8, 8 and 7 calves received milk from cows fed on a basal diet without addition of plant extracts (CON), with addition of 10.0 g of oregano extract (OE) per day and with 5.0 g of green tea extract (GT) per day, respectively. On days 1, 30, and 60 after birth redox state biomarkers were evaluated. Body weight was eval-uated every two weeks, rectal temperature and fecal score were accessed every two days and concentrate intake was measured every day. Statistical analyses for body weight, body weight gain, concentrate intake, rectal temperature, variables of redox status were performed using the procedure Mixed, evaluating the fixed effects of treatment, day of measurement and their interaction. Statistical analyses for the mean fecal score and the number of days to the first diarrhea occurrence were performed using the procedure Mixed, evaluating the fixed effect of treatment. On day 1, calves fed with milk from GT group had higher plasma glutathione peroxidase activity (GPx) than CON. However, the reverse occurred on day 60. On the day 1, calves in the CON group presented higher concentrations of thiol groups (also known as sulfhydryl groups) than those in GT and OE groups, with reverse occurring on day 30. Calves in the OE group had lower oxidation of dichlorofluorescein in the erythrocytes compared to the others; while calves in the GT group presented higher concentration of GSH and higher activity of the catalase enzyme compared to CON and OE, respectively. Pre-weaned calves fed with milk of cows supplemented with extracts of green tea and oregano did not change..

    Milk production and hematological and antioxidant profiles of dairy cows supplemented with oregano and green tea extracts as feed additives.

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    We aimed to evaluate the effects of the addition of oregano (Origanum vulgare) or green tea (Camellia sinensis L.) extracts (separately and associated) on feed intake, milk production, and hematological and antioxidant profiles of dairy cows. For that purpose, 16 Holstein and 16 Holstein-Gyr cows with 526.3±10.2 kg and within the first third of lactation were distributed according to a complete block design with measurements repeated in time. Treatments were control (CON), addition of 0.056% of oregano extract (OR), addition of 0.028% of green tea extract (GT), addition of a mixture of OR and GT extract (0.056% each) in the diet (MIX). Hematological and antioxidant profiles were monitored. Data were subjected to ANOVA, with block, treatment, days, and their interactions considered as fixed effects and animal and the residue as random effects. In Holstein cows, GT increased feed intake and milk yield compared with CON; in Holstein-Gyr crossbred cows, OR showed increased intake and GT increased milk yield compared with CON. Compared with CON, GT and OR decreased eosinophils concentration; OR showed the highest neutrophils concentration and neutrophils to leukocyte ratio. Compared with CON, OR presented increased catalase (CAT) activity, while GT increased the reduced glutathione concentration. The MIX treatment reduced CAT activity compared with OR, presented the lowest concentration of oxidized dichlorofluorescein in the erythrocytes (DCFER) and plasma (DCFPLA), and increased eosinophils concentration compared with GT and OR. Extracts differently affected feed intake and milk yield depending on genetic group. Feeding green tea and oregano extracts separately or associated distinctly affects the antioxidant indicators of lactating dairy cows

    Clonal Relationship among Atypical Enteropathogenic Escherichia coli Strains Isolated from Different Animal Species and Humans▿

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    Forty-nine typical and atypical enteropathogenic Escherichia coli (EPEC) strains belonging to different serotypes and isolated from humans, pets (cats and dogs), farm animals (bovines, sheep, and rabbits), and wild animals (monkeys) were investigated for virulence markers and clonal similarity by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The virulence markers analyzed revealed that atypical EPEC strains isolated from animals have the potential to cause diarrhea in humans. A close clonal relationship between human and animal isolates was found by MLST and PFGE. These results indicate that these animals act as atypical EPEC reservoirs and may represent sources of infection for humans. Since humans also act as a reservoir of atypical EPEC strains, the cycle of mutual infection of atypical EPEC between animals and humans, mainly pets and their owners, cannot be ruled out since the transmission dynamics between the reservoirs are not yet clearly understood
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