Adriana Guim

Potential of Caatinga forage plants in ruminant feeding

Caatinga is the most important biome for the livestock in the Brazilian semi-arid region. This review paper aimed to present information on different forage aspects of caatinga vegetation for ruminant feeding. Caatinga vegetation is formed mainly by shrubs and small trees, usually presenting thorns, deciduous leaves, and leaf abscission occurring frequently at the onset of the dry season. Additional components of the botanical composition in this biome includes the families cactaceae, bromeliaceae, and a herbaceous component formed by grasses, legumes, and forbs, often presenting annual cycle. Quantitative information of caatinga vegetation is scarce in the literature, mainly for the herbaceous stratum. Methodological aspects such as lack of standardization across evaluations make comparison regarding forage potential of caatinga plant species difficult. Index species must be identified within each caatinga type. Quantitative aspects of biological N2 fixation by caatinga species have not been extensively studied. Regarding forage nutritive value, it is necessary to study N availability for ruminants in caatinga plants, since large proportion of this element may bind to fiber components (ADIN). Manipulation of caatinga vegetation is an alternative to change forage quantity and quality for grazing animals, affecting their performance as a result. Studies measuring qualitative and quantitative variability of native forage resources from caatinga are mandatory in order to improve animal feeding management, with the ultimate goal of creating sustainable animal production based on caatinga vegetation.

Estabilidade aeróbica de silagens de capim-elefante (Pennisetum purpureum, Schum) emurchecido e tratado com inoculante microbiano

An experiment was carried out at UNESP, Jaboticabal Campus to evaluate the effect of a microbial inoculant on aerobic stability of wilted grass silage (Pennisetum purpureum, Schum). The grass was cut with 96 days of growing, remaining under sun action 5 hours to wilt. Silages were made in plastic silos, 0.2m3 capacity, that received (CI) or not (SI) inoculant at the ensilage time. For the study of aerobic deterioration, each silo was subdivided in three levels and the silages were exposed in a system, used to evaluate CO2 production, for 2 (T2), 4(T4), 6(T6) and 8(T8) days. Surface silage had higher pH value, lower NH3-N content, and higher yeast count than middle and bottom silages. The significant interaction between inoculation and aeration stage, shown that at earlier stages (T0, T2 and T4) there was no difference between treated and control silages in pH, N-NH3 and mold count, but at later stages (T6 and T8), inoculated stages had lower pH value, mold count and tended to a lower CO2 production, showing a lower deterioration speed after 6 days of aerobic exposure.

Evaluation of botanical composition of sheep diet in Caatinga pasture

This study was carried out to evaluate the effect of cannula placement site and hour of collection on the botanical composition of sheep diet. Ten castrated sheep Santa Ines breed were used, with five of them using permanent ruminal cannula and the five others with esophageal cannula. Water and mineral mix were available ad libitum. Samples collected from both cannulas revealed 39 species with an average of 20 species occurring in each monthly sampling. In addition, other Poaceae species were not identified. There was a significant effect of collection time on the botanical composition and on the plant fractions selected by the sheeps. Leaf was the most consumed fraction, corresponding to 55% of the extrusa sample. Stem proportion was affected by month x hour of collection interaction. There was no effect of the place of fistula or time of collection on botanical composition of the diet, however, the interaction of month of collection, fistula placement and, time of collection affected botanical composition and proportion of plant fractions consumed. The selectivity index varied during the study for several species, being directly related to the ingestive behavior of the sheep. Feed selected by sheep presented a large number of plant species with malvaceae and poaceae being the most important families. Ruminal cannula instead of esophageal cannula can be used to characterize the botanical composition of the diet consumed by small ruminants.

Composição química e degradabilidade in situ da ração em ovinos em área de caatinga no sertão de Pernambuco

This work was conducted with the objective of evaluating the effect of the type of fistula and time of collection on the chemical composition and in situ digestibility of dry matter, neutral detergent fiber and crude protein in the caatinga region. The experiment was conducted between September 2004 and July 2005. Ten Santa Ines castrated sheep, five with permanent ruminal cannula and five with esophageal cannula, were used. Samples were collected from both cannulas at 7:00 am and 2:00 pm. Sheep had free access to water and mineral mix. The percentage of DM, MM, CP, EE, NDF, ADF, NDIP, ADIP, CHOT, NFC, FT, TT and TC ranged from 11.99 to 25.28%; 10.92 to 14.44; 10.64 to 17.19%; 2.95 to 4.77; 54.83 to 63.14%; 39.40 to 46.62%; 49.74 to 57.95; 28.52 to 39.15; 65.40 to 72.73; 5.47 to 12.86%; 0.37 to 0.52%; 0.16 to 0.28%; and from 1.28 to 6.24%, respectively. Potential degradability (%), fraction B (%), fraction C (%/h), fraction A (%), effective degradability and passage rate of 2 and 5%/h ranged from 48.25 to 64.63; 35.77 to 47.78; 4.60 to 13.40; 9.74 to 18.13; 43.28 to 55.71 and 37.60 to 47.27 for dry matter; from 36.43 to 54.34; 33.28 to 50.38; 3.84 to 8.42; 2.16 to 4.41; 29.21 to 36.54; 23.02 to 33.33 for neutral detergent fiber and from 62.13 to 77.24; 35.44 to 56.09; 5.37 to 14.36; 20.21 to 31.49; 55.84 to 67.49; 45.74 to 59.99 for protein, respectively. The chemical composition and in situ digestibilility of diets for sheep in caatinga is influenced by the month of evaluation. The diet for sheep in the caatinga region presented low in situ digestibility of dry matter, neutral detergent fiber and crude protein. Ruminal cannula instead of esophageal cannula can be used to characterize the chemical composition and degradability of diet consumed by small ruminants.

Rendimento e composição químico-bromatológica de fenos triturados de gramíneas tropicais

The research was carried out to evaluate yield, chemical composition and losses of chopped tropical grass hays with the following forages: pearl millet (Pennisetum americanum), sudangrass (Sorghum sudanense), elephantgrass (Pennisetum purpureum) and two cultivars of forage sorghum (SF-25 and IPA-467-4-2) (Sorghum bicolor). The materials were harvested at 30% flowering, except for elephantgrass (60 days). The experiment was conducted according to a complete randomized block design, with five treatments and four replications. There were significant differences among hay productions with sorghum cultivars IPA-467-4-2 and SF-25 reaching the highest yields (10.85 and 10.65 t/ha/cut). Production of elephantgrass, sudangrass and pearl millet hays were respectively of 6.94, 6.69, and 4.93 t/ha/cut. Percentage of hay losses were not different among all treatments and varied from 17.33 to 20.17%. Pearl millet and sudangrass hays had the highest CP concentrations (10.56 and 8.80%), which were superior to elephantgrass (6.76%) and sorghum cultivars (5.62 and 5.50%). Most of the NDF values were superior to 70.0%. Sorghum cultivars exhibited the lowest NDIN concentration (0.42 and 0.40% of DM). The ADIN concentration ranged from 0.06 to 0.30% of DM. The highest lignin (%DM) concentration was observed for pearl millet (6.52%) and sorghum IPA-467-4-2 (6.17%) hays. Estimated TDN of the hays showed significant differences and sudangrass reached the highest value (53.35%). Production of chopped tropical grass hays showed high yields and chemical composition according to the minimum standards for ruminant nutrition.

Efeitos da adição de vagens de algaroba sobre a composição química e a microbiota fúngica de silagens de capim-elefante

Este trabalho foi conduzido com o objetivo de avaliar o efeito da adicao de vagens de algaroba ao capim-elefante sobre a composicao quimica e a microbiota fungica das silagens. Os tratamentos constaram de silagens formadas pela associacao de capim-elefante e vagens de algaroba nas seguintes proporcoes: 100:0; 67:33; 34:66 e 0:100. O delineamento experimental foi o inteiramente casualizado, com quatro tratamentos e quatro repeticoes. As silagens foram confeccionadas em mini-silos de PVC, mantidos lacrados por 120 dias. Apos abertura dos silos, foram coletadas amostras das silagens para isolamento e identificacao dos fungos e avaliacao da composicao quimica das silagens. A adicao de vagens ao capim-elefante reduziu linearmente os teores de FDN, FDA e cinzas (MM) e aumentou o de MS. Um total de 490 unidades formadoras de colonias (UFC) foi isolado por g de material e apresentou a seguinte distribuicao: 68; 101; 261 e 58 UFC/g de silagens, respectivamente, nos tratamentos 100:0; 67:33; 34:66 e 0:100. A adicao de vagens aos silos alterou a microbiota fungica das silagens. No tratamento contendo somente silagem de algaroba, houve maior diversidade de especies fungicas, apesar da menor contagem de UFC/g de amostra, enquanto, no tratamento com 66% de algaroba, observaram-se maior crescimento de fungos e menor diversidade de especies fungicas.

Substituição da palma-gigante por palma-miúda em dietas para bovinos em crescimento e avaliação de indicadores internos

Objetivou-se avaliar a substituicao da palma-gigante por palma-miuda em dietas para bovinos em crescimento sobre o consumo e a digestibilidade dos nutrientes. Tambem foram avaliados dois periodos de incubacao (144 e 288 horas) para obtencao da fracao indigestivel da materia seca, fibra em detergente neutro e fibra em detergente acido. Utilizaram-se cinco novilhas da raca Holandesa com peso inicial de aproximadamente 220 kg, distribuidas em quadrado latino 5 × 5 e alojadas em baias individuais cobertas, com piso de concreto e dotadas de comedouros de alvenaria e bebedouros individuais. As dietas experimentais foram a base de palma forrageira, bagaco de cana, farelo de soja, ureia e mistura mineral nas proporcoes 38,0; 42,0; 18,0; 0,5 e 1,5% na base da materia seca, respectivamente, com 0; 25; 50; 75 ou 100% de substituicao da palma-gigante pela palma-miuda. Os consumos e a digestibilidade de materia seca, materia orgânica, proteina bruta, extrato etereo, nutrientes digestiveis totais, carboidratos totais, carboidratos nao-fibrosos e fibra em detergente neutro, nao foram afetados pela substituicao. A materia seca indigestivel (incubada por 144 horas), a fibra em detergente neutro e a fibra em detergente acido indigestiveis (incubadas por 288 horas) permitiram estimar a producao de materia seca fecal e a digestibilidade de materia seca de maneira semelhante ao metodo de coleta total de fezes. A palma miuda pode substituir integralmente a palma gigante e a materia seca indigestivel incubada por 144 horas e a fibra em detergente neutro e fibra em detergente acido indigestiveis incubadas por 288 horas podem ser utilizadas em estudo de digestibilidade com ruminantes.

Elephant grass clones for silage production

Ensiling warm-season grasses often requires wilting due to their high moisture content, and the presence of low-soluble sugars in these grasses usually demands the use of additives during the ensiling process. This study evaluated the bromatological composition of the fodder and silage from five Pennisetum sp. clones (IPA HV 241, IPA/UFRPE Taiwan A-146 2.114, IPA/UFRPE Taiwan A-146 2.37, Elephant B, and Mott). The contents of 20 Polyvinyl chloride (PVC) silos, which were opened after 90 days of storage, were used for the bromatological analysis and the evaluation of the pH, nitrogen, ammonia, buffer capacity, soluble carbohydrates, and fermentation coefficients. The effluent losses, gases and dry matter recovery were also calculated. Although differences were observed among the clones (p < 0.05) for the concentrations of dry matter, insoluble nitrogen in acid detergents, insoluble nitrogen in neutral detergents, soluble carbohydrates, fermentation coefficients, and in vitro digestibility in the forage before ensiling, no differences were observed for most of these variables after ensiling. All of the clones were efficient in the fermentation process. The IPA/UFRPE TAIWAN A-146 2.37 clone, however, presented a higher dry matter concentration and the best fermentation coefficient, resulting in a better silage quality, compared to the other clones.

Anatomia e cinética de degradação do feno de Manihot glaziovii

Anatomy and kinetics of degradation of Manihot glaziovii Hay. This study the structural components of cell wall with its degradability, chemical composition, secondary compounds, in situ degradability, anatomy and tissue degradability of the hay of “maniçoba” (wild cassava) from plants in early fruiting, from savanna vegetation in Ibimirim, Pernambuco. The stem showed cells with varied degrees of lignification, highlighting the presence of gelatinous fibers, lignified pith parenchyma and thick cell walls inside the xylem. The leaves were highlighted by the presence of a girder structure, characterized by the great quantity of mesophyll, constituted by cells with thin walls, contributing to the degradability of dry matter. Idioblasts with druses of oxalate were observed around the vascular tissues, in the midrib. It works like defense mechanisms of plant against herbivores and can affect the availability of minerals for animals. “Maniçoba” hay, in spite of its advanced maturity stage (early fruit development), presents adequate chemical composition and low concentration of cianidric acid and tannins. The mains limits to degradability are cell wall thickness and lignification, particularly in stem tissue. Additionally, several aspects reported here induce to the continuity of studies in several focuses and aim to improve the use this specie as forage.

Substituição total do milho e parcial do feno do capim-tifton por palma forrageira em dietas para vacas em lactação. Produção, composição do leite e custos com alimentação

O experimento foi conduzido com o objetivo de avaliar a influencia de dietas com teores crescentes de palma forrageira sobre a producao, a composicao do leite e o perfil dos acidos graxos do leite de vacas holandesas em lactacao. Os animais (583 ± 7,07 kg) foram alimentados com dietas formuladas com diferentes niveis (0; 12,0; 25,0; 38,0 e 51,0%) de palma forrageira (Opuntia ficus indica Mill) em substituicao total ao milho (Zea mays L.) e em substituicao parcial ao feno de capim-tifton (Cynodon spp). Foram utilizadas cinco vacas distribuidas em um quadrado latino 5 x 5. Cada periodo experimental teve duracao de 17 dias, dez para adaptacao dos animais a dieta e sete para coleta de dados. A producao de leite, total (kg/dia) e corrigida para 3,5% de gordura (kg/dia), o teor de gordura (%) e a producao de gordura (kg/dia) do leite (20,65; 19,76; 3,73 e 0,745, respectivamente) nao foram influenciados pela introducao de palma nas dietas. O perfil de acidos graxos da gordura do leite nao foi influenciado (quanto aos acidos caprico, laurico, miristico, linoleico, linolenico e araquidico) pelos niveis de palma na dieta, entretanto, houve aumento linear dos acidos de cadeia intermediaria (palmitico e palmitoleico) e tendencia inversa para os acidos estearico e oleico. A inclusao de palma forrageira em substituicao ao milho e parte do feno de capim-tifton para vacas holandesas em lactacao nao influenciou a producao e a composicao do leite, exceto a concentracao dos acidos graxos de cadeia longa, que apresentou comportamento linear decrescente.