Herbage allowance, movement and weight of goats in two sites of Caatinga (dry tropical forest)

Abstract

The objective of this study was to quantify the forage yield, determine its nutritive value, and evaluate the movement pattern, weight variation and body condition score of goats managed on sites of the Brazilian Caatinga grassland (Dry Tropical Forest) in different seasons, at the Lisboa settlement located at the south bank of Piauí river, in the towns of São João do Piauí and Pedro Laurentino at Capivara mountain, Piauí, Brazil, in two study sites, one constituted by shrubby Caatinga (site I) and the other by arboreal Caatinga (site II). The highest forage mass value (1,534.57 kg DM ha⁻¹) was recorded on the arboreal site. The mass of forage plants found on the sites differed among plants and months. The species Senna macranthera had the highest yield in March (177.35 kg DM ha⁻¹) on the shrub site, while Arrabidaea ateramnantha had the highest yield in February (710.65 kg DM ha⁻¹) on the arboreal site. The litter mass differed among sites, with the greatest amount found on the shrub site (1,785.96 kg DM ha⁻¹). Crude protein, acid detergent fiber, acid detergent insoluble nitrogen and in vitro dry matter digestibility contents were greater on the arboreal site. Dry matter and protein differed among months, showing an inversely proportional relationship. Litter nutritional variables did not differ (p < 0.05). In the Caatinga, goats travel an average of 6.24 km day⁻¹, with maximum movement of 7.36 km day⁻¹ in the dry season. The highest weight of the goats (33.06 kg BW) and the lowest body score (2.53) occurred in the transition season from the rainy to the dry season, and the lowest weight occurred in the dry season (26.93 kg BW). The botanical composition of the grassland determines the forage mass between months of the year. In this semi-arid region, goats follow a movement pattern defined by the herbage allowance and water availability.