Chemical Composition of Species with Forage Potential in Different Physiographical Zones of Pernambuco.

Understanding the forage potential of rangeland species is important because they fit well into the prevailing environmental conditions in the semiarid. The research was performed in Serra Talhada, Flores, Sertânia, Arcoverde, Pesqueira, Tacaimbó, Bezerros, and Vitória de Santo Antão, cities localized in different Physiographical zones of Pernambuco, Brazil. Bushes and shrubby species (5 mm diameter and 1.5 m height) were sampled and placed into an oven dryer at 55°C and grounded thereafter. Response variables measured included ashes, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin and the C:N ratio. Soil samples were collected at depths from 0 to 20 cm. In general, the soils were considered loamy, eutrophic, with low acidity and average to high fertility. Data were subjected to descriptive statistics (mean and confidence interval at 5% of probability). The chemical composition varied among species, sites, and plants within species and sites. Ashes ranged from 3.8 ± 0.3% (Mimosa tenuiflora Willd., in Bezerros) to 24.0 ± 6.0% (Macroptilium martii Benth., in Flores). The NDF ranged from 31.7 ± 1.4% (Myracrodruon urundeuva All., in Serra Talhada) to 64.4 ± 0.1% (Sida galheirensis Ulbr., in Flores). The ADF ranged from 14.2 ± 2.6% (Myracrodruon urundeuva All., in Serra Talhada) to 50.8 ± 9.4% (M. tenuiflora, in Pesqueira). The acid detergent lignin ranged from 5.2 ± 1.0% (Tephrosia sp., in Tacaimbó) to 39.4 ± 8.8% (M. tenuiflora, in Pesqueira). The CP ranged from 9.2 ± 0.9% (Aspidosperma pyrifolium Mart., in Sertânia) to 21.7 ± 0.7% (Leucaena leucocephala Lam., in Tacaimbó). The C:N ratio ranged from 10.7 ± 0.6% (Indigofera suffruticosa Mill., in Sertânia) to 31.4 ± 2.2% (Aspidosperma pyrifolium Mart., in Sertânia). The plants analyzed have forage potential based in their chemical composition. However, evaluations such as digestibility and toxicity are needed.