Corn production for silage intercropped with forage in the farming-cattle breeding integration

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determinação da melhor dose de virginiamicina em suplementos para bovinos Nelore em pastejo

Pós-graduação em Zootecnia - FCAV

Características morfogenéticas, perdas de nitrogênio por volatilização, reservas orgânicas e sistema radicular do capim-Tanzânia fertilizado com doses de nitrogênio

O objetivo do trabalho foi estudar as características morfogenéticas e estruturais do capim-Tanzânia, a produção de forragem, as perdas de nitrogênio (N) por volatilização, reservas orgânicas e a avaliação do sistema radicular sob doses de nitrogênio sob pastejo. O experimento foi instalado na área Fazenda Experimental de Iguatemi da Universidade Estadual de Maringá, no período de março de 2007 a março de 2008. O delineamento experimental utilizado foi de blocos completos ao acaso, com parcelas subdivididas com quatro repetições. Nas parcelas, encontravam-se as doses de N (0, 150, 300 e 450 kg ha-1 de N) e, nas sub-parcelas, as estações do ano. As perdas de N por volatilização foram quantificadas depois da adubação N (1, 2, 3, 6, 9, 12 e 15 dias). As amostragens das raízes foram realizadas nas profundidades de 0-10, 10-20 e 20-40 cm. A aplicação do fertilizante N na pastagem foi parcelada em três aplicações. A produção de massa seca total e de lâmina foliar de forragem respondeu linearmente até 282 kg ha-1 de N na estação do verão. A adubação nitrogenada exerce efeito positivo nas taxas de alongamento e aparecimento foliar, e no número de folhas vivas em plantas de capim-Tanzânia nas estações da primavera e verão. Elevadas adubações nitrogenadas associada a intervalos menores de pastejo promovem uma maior porcentagem de lâmina foliar; no manejo de pastos de capim-Tanzânia sob lotação rotacionada com altura de 70 cm na entrada dos animais para o pastejo e saída com 30 cm de altura do resíduo. A interação entre o nível de adubação e o período depois da aplicação de uréia foi significativa para a variável volatilização acumulada de N-NH3. A aplicação da uréia acarreta perdas percentuais mais elevadas de N nos três primeiros dias após a aplicação. A perda média acumulada de N-NH3 no período para as três estações do ano... (Resumo completo, clicar acesso eletrônico abaixo)

Simple agrometeorological models for estimating Guineagrass yield in Southeast Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Valor nutricional de silagem de capim-mombaça com aditivos agroindustriais

It was aimed to evaluate the chemical composition of grass silage-mombasa associated with different additives in four times of opening the silo. The experiment was conducted in UFGD. After harvesting the forage, biomass in natura crushed, was taken to the lab, homogenized and enriched on the basis of natural mass, with the following additives: 5% wheat bran, 5% of waste (broken grain and soy ice cream cone) of soybean, 5% urea in natural matter and the witness (without additive). The silos were opened after (unprocessed material), 15, 30 and 45 days, for the analysis of chemical composition. The data obtained were analyzed through the statistical programme SISVAR and averages were compared to 5% of probability, by Skott-Knot. The grass silage-mombasa without additive presented major (P<0.05) dry matter content compared to other treatments at time 0 and 30 days of silage and did not differ (P>0.05) of grass silage- mombasa associated with 5 of urea in 15 days and 45 of silage. The grass silage-mombasa with 5% urea showed the highest crude protein content at time 0 and differed from other treatments. The silage of mombasa associated with 5% urea provided greater in vitro digestibility of dry matter to 15 days of silage.

Degradação de palhada e liberação de nitrogênio por plantas de cobertura sob plantio direto

Crops used to cover the ground may also release nitrogen into the soil during mineralization. However, it is necessary to identify species that combine fast nutrient release and longer permanence of the straw on the soil surface. The aim of this study was to investigate straw degradation and nitrogen release from cover crops under no-tillage cropping systems. The field trial was performed during two growing seasons in summer (2008/2009 and 2009/2010) in the Cerrado region of Brazil. The experimental design was a randomized block in factorial arrangement. Treatments were the combination of five plants (four cover crops species, 1 - Panicum maximum, 2- Brachiaria ruziziensis, 3. Brachiaria brizantha and 4. Pennisetum glaucum [millet], and fallow as a control) with six sampling times (first six weeks after application of glyphosate on the cover crops). Pennisetum glaucum and fallow showed faster straw degradation and nitrogen release. The cover crops Panicum maximum, Brachiaria brizantha and Brachiaria ruziziensis stood out in biomass production and in the amount of nitrogen in their shoots but had the lowest coefficients of degradation and persisted longer on the soil surface than Pennisetum glaucum and fallow.

MORPHOGENESIS AND PRODUCTION OF TANZANIA, MOMBACA AND MULATO GRASSES UNDER NITROGEN FERTILIZATION

A field trial was conducted designed in a completely randomized block in a 4 x 3 factorial arrangement to evaluate the application of nitrogen doses (N) (0, 40, 80 and 160 kg/ha) on the morphogenical characteristics and dry matter partition of three forage grasses (Panicum maximum cvs. Mombasa and Tanzania and Brachiaria sp. Hybrid Mulato). The leaf appearance (LAR, leaf/day) and stretching (LER; mm/day) rates, the number of green leaves per tiller (NLT) and the average weight of tillers (MTW; g) presented s positive linear response to the N dose while the phyllochron (Phil; day/leaves) showed a negative linear response. The highest LER, IAL and final leaf length (FLL; cm) occurred in the Mombaca and Tanzania grasses, while the highest LAR occurred in the Mulato grass. There was a negative quadratic effect of the N dose on the stem elongation rate (SER; mm/day) and LF. The Mombaca and Tanzania grasses presented the highest SER; however, in just two forages. The production of total dry matter (TDM; kg/ha), leaves (LDM; kg/ha) and stems (SDM; kg/ha) increased linearly and quadratically with the N dose, respectively, for the Mombaca and Tanzania grasses. There was a high positive correlation among DM, LDM and SDM and the Mombaca grass MTW. The dry matter production and morphogenic characteristics were influenced by the nitrogen fertilization as a result of the substantial increase in the flow of tissues stimulated by fertilization, proving the importance of N for forage biomass accumulation.

Desempenho, qualidade de carcaça e da carne de cordeiros alimentados com dietas contendo silagens de milho consorciadas ou não com capins tropicais

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Eficácia de óleos minerais aplicados como adjuvantes auxiliando na selitividade de herbicidas na cultura de cana-de-açúcar

Pós-graduação em Agronomia - FEIS

Performance and parasite control of different genetic groups of lambs finished in irrigated pasture

The aim of this study was to compare the following four genetic groups of hair sheep: Santa Inês (SI), Morada Nova (MN), Brazilian Somali (BS), and the F1 1/2Dorper x 1/2Morada Nova crossbreed on traits related to growth and parasitic infection. Thirty-three male lambs of the same age and of simple birth, under the same pre-weaning management conditions were used in the experiment. After weaning the animals were housed in a completely randomized design in paddocks made of Panicum maximum cv. Tanzania. Along the course of the research, the performance of the four groups of sheep was observed to be negatively affected by gastrointestinal parasites, but there was a genotype effect to the average daily weight gain (ADWG), where the SI and F1 genotypes presented higher values. The effects of genotype, time and genotype x time interaction were significant in weight and corporal score (CS) measurements. The BS lambs had the highest CS values throughout the experiment despite not presenting greater weight gain when compared to the SI and F1 breeds. There were also significant effects of time and genotype x time interaction for packed cell volume (PCV) and FAMACHA© score (FAM) and only the time effect was significant in the total number of eggs per gram (EPG) and total plasma protein (TPP). The MN lambs showed higher PCV values and unlike the other groups, presented a FAMACHA© score below 3 and PCV above 23% even having a higher EPG tendency, especially in the initial phase, indicating a possible higher resilience to infection caused by gastrointestinal parasites.

Interferência de plantas daninhas no desenvolvimento inicial de mudas meristemáticas de cana-de-açúcar

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Liberação de nutrientes da palhada de forrageiras consorciadas com milho e sucessão com soja

In tropical regions there is rapid decomposition of plant material deposited on the soil, and the ability to recycle nutrients through this decomposition is one of the most important aspects of cover crops. The aim of this study was to evaluate the yield and nutrient release from forage crops intercropped with maize for silage, and soybean in succession. The study was conducted in the experimental area of Universidade Estadual Paulista, Ilha Solteira campus, Brazil. The experiment consisted of maize for silage intercropped with four forage species (Urochloa brizantha cv. Marandu, Urochloa ruziziensis, Panicum maximum cv. Tanzania, and Panicum maximum cv. Aries) sown in three modalities: in the maize row, together with fertilizer; broadcast at maize sowing; and broadcast in the V4 stage of maize, in a randomized block design in a 4 x 3 factorial arrangement with four replications. The evaluation of nutrient release was performed during the soybean cropping that followed the intercropping by the litter bag method at 30, 60, 90, and 120 days after sowing of soybean. Panicum maximum cv. Tanzania showed higher dry matter yield when sown by broadcasting at maize sowing. Sowing of forages in the maize row, and through broadcasting at maize sowing led to greater dry matter yield for straw formation. Intercropping of maize with forages in the autumn is an alternative for increasing the amount of straw and cycling of macronutrients in a no-till system. Potassium was the nutrient with the greatest accumulation in the forage straws (up to 150 kg ha(-1)), with 100 % release at 90 days after sowing soybean. The forage straws are thus an excellent alternative for cycling of this nutrient. Panicum maximum cv. Tanzania sown by broadcasting at the time of maize sowing showed greater phosphorus cycling (13 kg ha(-1)). Panicum maximum cv. Tanzania broadcast in the V4 stage of maize is the option with least potential for straw production and nutrient cycling, while the other options (forages and sowing modalities) have higher potential for use, at the criteria of machine availability for setting up intercropping with corn.

Retrieval of Trichostrongylus colubriformis infective larvae from grass contaminated in winter and in spring

The survival of infective larvae (L3) of Trichostrongylus colubriformis was evaluated on Brachiaria, Coast-cross and Aruana forage grasses. Feces of sheep parasitized exclusively by T. colubriformis were deposited in winter and spring on experimental plots whose grasses were cut at two heights: 5 cm and 30 cm. One, two, four, eight, 12 and 16 weeks after depositing the feces, fecal and forage samples were collected for the retrieval and quantification of L3. Retrieval of L3 from feces and forage was negligible in winter due to the dry weather, although a few larvae were retrieved in the last larval collections. However, L3 retrieval from fecal samples was greater in spring, especially two weeks after feces were deposited on 30 cm high grasses. At this time, the L3 retrieval rate from the three forage grasses differed significantly (P < 0.05), with Aruana grass showing the highest average L3 retrieval rate, followed by Coast-cross and Brachiaria. In conclusion, the winter drought proved very unfavorable for the presence of L3 in the environment, and the microclimate of Aruana pastureland was generally the most favorable for the retrieval of infective larvae.

Ammonia volatilization losses in Tanzania grass fertilized with urea

Gaseous losses are the main factors affecting the efficiency of nitrogenous fertilizers in pastures. To evaluate NH3-N volatilization losses in Tanzania grass fertilized with urea in autumn, spring and summer, a completely randomized design with repeated measurements over time and fifteen replicates was used. Plots were represented by urea levels (50; 100 and 150 kg ha-1 N) and subplots by time after fertilization (1; 2; 3; 6; 9; 12 and 15 days). The interaction between fertilization leveland time after urea application was significant for the accumulated NH3-N volatilization. Urea application leads to higher percentage N losses in the first three days after application. The average cumulative NH3- N loss for the three occasions (different seasons of the year) was 28%, 20% and 16% of N applied for fertilizer doses of 50; 100 and 150 kg ha-1 of N, respectively. The season of the year influenced NH3-N loss pattern and volume, with the lowest values recorded in spring, followed by summer and autumn. The cumulative NH3-N volatilization loss varies from 78 to 90% up to the third day after application of the total NNH3 loss.

Correlações entre padrões hematológicos, parasitológicos e desempenho animal de ovelhas suplementadas com gordura protegida

The development of populations of gastrointestinal parasites resistant to antihelmintics has led to seeks new alternatives its control. Stimulation of natural immunity by means of animal nutrition has shown promising results in controlling nematodes in sheep. The addition of protected fat sources, containing essential fatty acids, may be an alternative due to many effects, among them, regulation of immunity expression and regulation of the inflammatory response by immune effectors. The aim of this study was to estimate correlations between haematological and parasitological patterns, animal performance through weight and body condition, under the influence of protected fat in ewes. Fifty Santa Ines sheep, in the final third of pregnancy or postpartum, in paddocks of Panicum maximum, received, individually, 200 g per day of concentrate, isonitrogenous and isocaloric diets, with or without the addition of protected fat. In general, except for total leukocytes and eosinophils, almost all of Pearson correlation coefficients of other variables were significant. However, the protected fat, in the amount offered, had no antihelmintic effect.