Effects of ionizing radiation on ovaries of Rhipicephalus (Boophilus) microplus (ACARI: IXODIDAE) in pre-laying phase

O Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) é uma espécie de carrapato presente nos países de clima tropical e parasitam diversos animais de interesse zootécnico, mas predominantemente, bovinos, e que está diretamente envolvido no complexo de doenças chamado de Tristeza Parasitária Bovina, causadas por infecções com Babesia spp, entre outras e, constituindo-se num fator limitante ao desenvolvimento da pecuária nos países tropicais e subtropicais. Assim, com o intuito de se propor uma alternativa para o controle populacional deste parasita, buscou-se avaliar os efeitos da radiação gama do 60Co no aparelho reprodutor das fêmeas por meio das técnicas como o ensaio do cometa e preparação histológica de fixação em hematoxilina e eosina (H-E) e, o bioensaio de encubação das posturas avaliar a taxa de eclodibilidade para aplicações à técnica do inseto estéril. Vinte e cinco fêmeas ingurgitadas em fase de pré postura foram irradiadas com doses de 0, 5, 10, 15, 20 e 25 Gy para ambos os experimentos (5 fêmeas/tratamento) e após 24h foram dissecadas e seus ovários formaram uma amostra. O ensaio do cometa mostrou que o trauma cromossômico foi proporcional às doses da radiação ionizante. Os achados histológicos demonstraram que à dose de 5 Gy teve aspecto morfohistológico semelhante ao controle; doses de 10 e 15 Gy não evidenciaram efetiva desnaturação dos pedicelos ou epitélio dos ovários, contudo, desarranjos das granulações do vitelo e a presença de numerosos vacúolos nos ovócitos, corroboram com a degeneração celular ou autofagia, o que comprometeria a viabilidade dos ovos. Doses de 20 e 25 Gy mostraram efeitos agudos com significativo comprometimento de toda estrutura do aparelho reprodutor comprometendo a postura. No bioensaio as fêmeas também em fase de pré postura foram submetidas às doses de 0 a 400 Gy e se constatou que a radiação ionizante afetou em aproximadamente 70% o peso da postura, a taxa de eclosão dos ovos da Testemunha foi 68,2% maior que a menor dose ionizante, que quanto maior a dose de radiação, menor o índice de eclosões e nos tratamentos que receberam doses maiores de 20 Gy, não ocorreram eclosões das posturas, estabelecendo-se assim um marco para se estudar a aplicação de técnica do inseto estéril neste espécime.The Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) is a species of tick present in tropical countries and parasites several animals of zootechnical interest, but predominantly bovine, and which is directly reserved in the complex of diseases associated with Bovine Parasitic Sadness, caused by infections with Babesia spp, among others and, constituting a limiting factor to the development of livestock in climatic and subtropical countries. Thus, in order to propose an alternative for population control of this parasite, you can evaluate the effects of the 60Co series on the female reproductive system using techniques such as the clinical or experimental hematoxylin and eosin (HE) assay and bioassay of hatching, evaluate hatchability rates for applications in sterile insect technique. Twenty-five engorged females in the pre-laying phase were irradiated with doses of 0, 5, 10, 15, 20 and 25 Gy for both experiments (5 females / treatment) and after 24 hours they were dissected and their ovaries formed a sample. The comet assay showed that the chromosomal trauma was proportional to the doses of the ionizing lesion. The histological findings demonstrated that the 5 Gy dose had a morpho-historical aspect similar to the control; doses of 10 and 15 Gy do not prove effective the denaturation of pedicels or ovarian epithelium, however, breakdowns of calf granulations and the presence of numerous vacuoles in the oocytes, corroborate with a cell degeneration or autophagy, or that compromise the viability of the eggs. Doses of 20 and 25 Gy have acute effects with significant impairment of the entire structure of the reproductive system, compromising posture. In the bioassay females also in the pre-laying phase was subjected to doses from 0 to 400 Gy and found that ionizing radiation affected approximately 70% or weight of the laying, a hatch rate of the witness eggs was 68.2% higher than is the lowest ionizing dose, which is the highest dose of injury, the lowest hatching rate and those receiving doses greater than 20 Gy, the postures do not hatch, establishing itself as a landmark for the study of a technical application for sterile in this species

Efeito de doses de composto de cama aviária sobre clorofila e flavonoides em Brachiaria brizantha brs Piatã

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Effect of doses of poultry compost on chorophyll and flavonoids of Brachiaria brizantha brs Piatã

In 2012, Brazil produced 12.6 million metric tons of chicken meat, generating 10.3 tons of poultry litter. Compost made from such organic waste can be used as a low-cost bio fertilizer, especially as nitrogen and phosphorus source. The compost can increase pastures quality by giving photosynthetic improvement and altering amounts of chlorophyll and flavonoids.  There is little information about the relationship between chlorophyll a or b and flavonoids in Brachiaria brizantha Piata. The flavonoid is a kind of polyphenol compound which protects the plant against UV-B radiation and pathogen attack, it acts as attractants for pollinators, as signal molecules for initiating plant-microbe symbiotic associations and antioxidant activity. The objective of the present study was verified the effects of poultry litter compost doses on the chlorophyll and flavonoid contents in Piata grass leaves. The experiment was performed at the Animal Nutrition and Pasture Center – Instituto de Zootecnia – Nova Odessa, SP, from May to July 2013, on a Haplorthox soil (pHCaCl2= 4.9), cultivated with Piata grass (Brachiaria brizantha, Stapf), without liming. The treatments consisted of five compost doses: 0; 20; 40; 60 and 120 Mg ha-1, with the following chemical composition (%): 2.88 of N, 3.85 of P2O5, 2.50 of K2O, 9.06 of Ca and 1.16 of Mg. The experimental design was on randomized blocks with five replications.  Chlorophyll amounts and flavonoids were determined by sampling the third medium of the leaf blade from  a third of the expanded leaf from the apical  using the Dualex and the chlorophyll a and b  which were determined by  the Lichtenthaler & Wellburn (1983) method.  Results showed that chlorophyll a was similar in all doses (average of 18.3 micrograms per cm2),therefore for chlorophyll b the amount was significantly increased from 7.3 to 22.4 micrograms per  cm2 (P<0.01)when compared to no addition of poultry litter. The fast nitrogen liberation from poultry litter resulted on a better metabolism and better chlorophyll b synthesis, indicating more mass production. Flavonoid contents decreased on the leaves of Brachiaria brizantha Piatã with the addition of poultry litter, from 1.39 to .81 micrograms per cm2, with respectively zero 120 Mg ha-1 of compost. Flavonoid content was negatively correlated to total chlorophyll, adjusted by the quadratic equation: Flavonoids= - 0.0353Chlorophyll + 2.29 (R2= 0.87). The use of increasing doses of poultry litter reduced the foliar flavonoids concentration

Efeito de doses de composto de cama aviária sobre clorofila e flavonoides em Brachiaria brizantha brs Piatã

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Comparação de métodos de avaliação de conteúdos de clorofila em Brachiaria brizantha brs Piatàadubada com composto de cama de aviário

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Chlorophyll evaluation methods in Brachiaria brizantha brs Piatã added with poultry litter compost

One of the major limitations for pastures high production is the low fertility of tropical soils. In general, the nutrient reposition through chemical fertilizers increases the cost of production and can unbalance the plant besides the environment pollution. Recycling solid residues from agribusiness is a sustainable alternative for farmers. Among the residues, the poultry litter (PL) aerobically fermented is a very good bio fertilizer for pastures. The Piatã Grass (Brachiaria brizantha) is a new option for the pasture market and can be used for bovine, equine or ovine. The fast diagnosis of the nutritional stage of this plant, based upon portable methods as the Dualex, measuring leaf light reflectance is a practical alternative.  By this way,  it is possible to offer to the herd high nutritional food, correcting eventual shortage, mainly nitrogen. Nitrogen nutrition is directely related to chlorophyll content in the leaf blade. This study aimed to verify the effects of doses of PL over total chlorophyll, in comparison to two methods of evaluation: Dualex Scientific 4.0 and Spectrophotometer Analysis according to Lichtenthaler & Wellburn (1983). The experiment was conducted in greenhouse conditions, at IZ, Nova Odessa, with a Haplortox soil, between May and July, 2013. Treatments consisted of five compost doses (PL): 0, 20, 40, 60 and 120 Mg ha-1, with the following chemical composition (%): 2.88 of N, 3.85 of P2O5, 2.50 of K2O, 9.06 of Ca and 1.16 of Mg. The experimental design was on randomized blocks with five replications. Data were analyzed using the GLM procedure of the SAS program. Chlorophyll data were taken from the third medium of the leaf blade from a third of the expanded leaf from the apical using the Dualex. At the same time, samples were harvested for the Spectrophotometer analyses according to methodology described by Lichtenthaler & Wellburn (1983). Total Chlorophyll amounts were increased with the higher doses of PL, adjusting quadratic to the equations: Chlorophyll-Dualex= -0.003PL2 + 056PL + 28.9 (R2= 0.84), and for Lichtenthaler & Wellburn methods Chlorophyll = -0.003PL2 + 0.052 PL + 24.8 (R2=0.76). Chlorophyll values were similar with both methods used. The Dualex method is faster and easier than the spectrometric method. The use of PL disables the improvement of photosynthetic potential and forage yield. Further studies are necessary to determine the correct use of those organic residues in degraded areas as well as in small production areas

Comparação de métodos de avaliação de conteúdos de clorofila em Brachiaria brizantha brs Piatã adubada com composto de cama de aviário

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Evaluation of micronutrient in soil treated with organic fertilizer

Taking advantage of organic fertilizer for use in agriculture, may have beneficial effects for supplying organic matter and nutrients to the soil. The tested organic fertilizer is produced in a system of thermophilic composting of sewage sludge, the process by which it is mixed with chopped pruning urban, the crushed sugar cane and eucalyptus bark, and the mixture is subjected to aeration process revolving mechanical and oxidation promoted by an intense activity of microorganisms. The same is also additived with gypsum (Ca2SO4) in order to reduce the losses of ammonia from the process, helping to prevent odors and also attraction of vectors, besides enriching the material with calcium and sulfur, two macronutrients in plants. On the other hand the application of such compounds should be carefully monitored in order to prevent environmental risks from its use. This work aimed to evaluate the effect of rates of organic fertilizer (OF), in the Instituto de Zootecnia (IZ), in a Typic Acrudox soil, pHCaCl2= 4.9, cultivated with Aries grass (Panicum maximum, Jacq.), without liming and focused in soil micronutrients contents. Treatments involved four rates of OF application: 0, 1.5, 3.0 and 4.5 t ha-1, mixed with soil before sowing the grass. The experimental design was a randomized blocks, with five replications, in pots (3.34 dm3). Soil samples were collected prior to the experiment (original soil) and after cultivation of the Aries grass. Were air dried and passed through sieves with mesh size of 2 mm and analyzed chemically. The micronutrients (B, Cu, Fe and Zn – mg dm-3) were determined by atomic absorption, after extraction with a solution of DTPA, pH 7.3 (RAIJ et al., 2001). Data were analyzed by the mixed procedure of SAS V. 9.2; average qualitative treatments were compared by Tukey test at 5% probability. The degrees of freedom related to N rates (quantitative treatment) were decomposed into orthogonal polynomials; to obtain the best equation fits the data. OF at a dose of 1.5 kg ha-1 was sufficient to raise the contents of Cu, Zn at levels considered medium and not limiting, however this rate for boron has resulted in high levels in the soil. Boron content in soil increased linearly with the addition of OF from 0.13 to 58.2: B = 12.2(OF + 0.28), R2=0.96. Typical visual symptoms of B toxicity were observed in the leaves of Aries grass at rates above 1.5 t ha-1 OF, that is, the burning of leaves, chlorosis and necrosis, often at the edges and tips of older leaves. Zn contents in analysis by extractant DTPA, varied from 0.7 to 5.1, according to the equation Zn= 0.93(OF+ 0.48), R2=0.93. Cu content varied from 0.21 to 0.61, Cu= 0.087(OF + 1.97), R2= 0.92. The use of organic fertilizer should be monitored very carefully, using small rates, because of the risks of causing harmful accumulation of heavy metals in soil. Thus it can result in nutrient imbalance, with restrictions on plant growth and environmental contamination

Avaliação de micronutrientes em solo tratado com fertilizante orgânico

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Avaliação de micronutrientes em solo tratado com fertilizante orgânico

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