Physiology of nutrition and feeding of farm animals is an essential factor influencing production efficiency and its quality. For these factors is important to provide optimal supply of nutrients by suitable feeds. Felicitous feed ration raise the economic realization of genetic potential of animals. Therefore we have to know the nutritional requirements of animals, including microorganisms, whose function in the diet of cattle is irreplaceable. The aim of this study was to determine the nutritional value of forage and lupine feeds (n = 8) by laboratory methods. Samples were analyzed for individual feed nutrients (crude protein (CP), fat, crude fiber, ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL)), gross energy and nitrogen fractions, and the results were statistically processed. Determination of individual nitrogen fractions was according to methods of Licitra et al. (1996). For this purpose were used following laboratory methods: (1) determination of non-protein nitrogen (NPN) (2), determination of soluble nitrogen and protein, (3) determination of nitrogen insoluble in acid detergent (ADIP), (4) determination of nitrogen insoluble in neutral detergent (NDIP). From these were obtained the results of NPN, IP (insoluble protein), SOLP (soluble protein), ADIP (nitrogen insoluble in acid detergent) and NDIP (insoluble nitrogen in neutral detergent). Averaged values (g.kg-1 of dry matter) of were 144.3 for NPN, 97.5 for IP, 78.7 for SOLP, 30.4 for ADIP and 80.3 for NDIP. Nitrogen fractions, i.e. fraction A (nonprotein nitrogen), fraction B1 (rapidly degraded protein), fraction B2 (intermediately degraded protein), fraction B3 (slowly degraded protein) and fraction C (bound protein) were calculated by equations of Ghoorchi and Arbabi (2010). The range of values was from 2.5 to 51.2 % of CP for fraction A, from 13.4 to 20.7 % of CP for fraction B1, from 0 to 19.9 % of CP for fraction B2, from 5.5 to 51.9 % of CP for fraction B3 and from 10.1 to 32.4 % of CP for fraction C.

Soil organic matter (SOM) is a well known indicator of soil quality due to its direct influence on soil properties such as structure, soil stability, water availability, cation exchange capacity, nutrient cycling, and pH buffering and amelioration. Study sites were selected in the Valley region of Virginia with the study objectives to: i) compare the efficiency of density solutions used in recovering free-light fraction (FLF) organic matter; ii) compare different soil organic fractions as sensitive indices of short-term changes in SOM due to management practices; iii) investigate on-farm effects of tillage management on soil organic carbon (SOC) and soil organic nitrogen (SON) stocks; and iv) evaluate the role of SOM in controlling soil available nitrogen (N) for corn uptake. The efficiency of the density solutions sodium iodide (NaI) and sodium polytungstate (SPT) in recovering FLF was the same at densities of 1.6 and 1.8 g cm⁻³, with both chemicals presenting less variability at 1.8 g cm⁻³. The sensitivity of SOM fractions in response to crop and soil management depended on the variable tested with particulate organic matter (POM) being the most sensitive when only tillage was tested, and FLF being the most sensitive when crop rotation and cover crop management were added. The on-farm investigation of tillage management on stocks of SOC and total soil N (TSN) indicated significant increases at 0–15 cm depth by increasing the duration (0 to 10 years) of no-tillage (NT) management (0.59 ± 0.14 Mg C ha⁻¹ yr⁻¹ and 0.05 ± 0.02 Mg N ha⁻¹ yr⁻¹). However, duration of NT had no significant effect on SOC and TSN stocks at 0–60 cm depth. Soil available N as controlled by SOM was modeled using corn (<i>Zea mays</i> L.) plant uptake as response and several soil N fractions as explanatory variables. The final model developed for 0–30 cm depth had 6 regressors representing the different SOM pools (active, intermediate, and stable) and a 𝑅² value of 65%. In summary, this study provides information about on-farm management affects on SOM levels; measurement of such effects in the short-term; and estimation of soil available N as related to different soil organic fractions. / Ph. D.

Submitted by (edna.saturno@ufrpe.br) on 2017-04-19T15:24:59Z No. of bitstreams: 1 Gilvan Silva.pdf: 106987 bytes, checksum: fdbe46a077a8dad5ef8dfbffda786440 (MD5) / Made available in DSpace on 2017-04-19T15:24:59Z (GMT). No. of bitstreams: 1 Gilvan Silva.pdf: 106987 bytes, checksum: fdbe46a077a8dad5ef8dfbffda786440 (MD5) Previous issue date: 2006-07-10 / The objective of this work was to evaluate chemical composition and digestibility of the fine and rough wheat bran. Samples of the food were analyzed for granulometry, water absorption and retention capacity, pH, matter dry (DM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (LIG), total carbohydrates (TCH) and no fiber carbohydrates (NFC), nitrogen fractions (A,B1, B2, B3 and C). Six male, non-castrated goats, 22 Kg live weight individually held in metabolism cages were used to evaluate the digestibility. The animals were fed Tifton hay (Cynodon dactylon) and fine or rough wheat bran (50:50 and 80:20 for fine wheat bran, and 60:40 e 70:30 for hough wheat bran). The equation system was used to determine the digestibility coefficients. Both wheat bran have similar pH, water absorption and retention capacity, and differ in particles granulometry. In fine wheat bran 99.3% of the particles are smaller than 1.18 mm, while in the rough one 31.3% are smaller and 68.4% are larger than 1.18 mm. The chemical composition was similar, except for CP, higher in the fine wheat bran (18.2 x 15.85%), NDF and ADF, higher in rough wheat bran (53.29 and 48.22% x 42.72 and 38.07%). Nitrogen fractions B2 and C were, respectively, 45% and 6% for bothwheat bran. The digestibility coefficients of DM, OM, CP, EE, TCHO, NDF, NDFcp, hemicellulose and cellulose were, respectively, 61.33, 68.62, 76.22, 70.00, 67.32, 66.78,65.75, 72.95, and 68.39% for rough wheat bran and 57.95, 60.36, 63.82, 59.29, 59.84, 56.92, 56.35, 65.23 and 58.56%. Fine and rough wheat bran can be used as an alternative food for goats feeding. / O objetivo deste trabalho foi avaliar a composição química e a digestibilidade dos farelos fino e grosso de trigo. Amostras dos alimentos foram analisadas para determinação da granulometria, capacidade de absorção e retenção de água, pH, matéria seca (MS), proteína bruta (PB), extrato etéreo (EE), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), lignina (LIG), carboidratos totais (CHOT) e não fibrosos (CNF), frações nitrogenadas (A, B1, B2 B3 e C). Para determinação da digestibilidade e dos nutrientes digestíveis totais (NDT), utilizaram-se seis caprinos machos, não castrados, com peso vivo médio de 22 Kg, alojados em gaiolas metabólicas. As dietas foram feno de Tifton (Cynodon dactylon) e farelo fino ou grosso em duas relações volumoso:concentrado (50:50 e 80:20 para o ensaio com o farelo fino, 60:40 e 70:30 para o ensaio com farelo grosso). Foi utilizado o sistema de equações para os cálculos de digestibilidade. Os dois farelos possuem semelhante pH, capacidade de retenção e de absorção de água, mas diferem na granulometria das partículas. No farelo fino 99,3 % das partículas são menores que 1,18 mm, enquanto no farelo grosso apenas 31,3 % são menores e 68,4 % são maiores que 1,18 mm. A composição química foi semelhante,exceto pelos percentuais de PB, maior no farelo fino (18,2 x 15,85 %), FDN e FDA, mais elevados no farelo grosso (53,29 e 48,22 % x 42,72 e 38,07 %). Ambos os farelos apresentaram em média 45% da fração B2 e 6% na fração C. O consumo de matéria seca da ração com farelo fino (661,75g/dia) foi superior àquela com farelo grosso (567,42 g/dia),entretanto, o consumo de NDT foi semelhante (383,94 e 437,62 g/dia, respectivamente). Oscoeficientes de digestibilidade da MS, MO, PB, EE, CHOT, FDN, FDNp, Hemicelulose e Celulose (61,33; 68,62; 76,22; 70,00; 67,32; 66,78; 65,75; 72,95 e 68,39%,respectivamente) do farelo grosso foram significativamente superiores (P<0,05) aos do farelo fino (57,95; 60,36; 63,82; 59,29; 59,84; 56,92; 56,35; 65,23 e 58,56%,respectivamente). Portanto, pode-se concluir que os farelos de trigo (fino e grosso) podem ser utilizados como alimento alternativo na alimentação de caprinos.