Canopy characteristics, animal behavior and forage intake by goats grazing on Tanzania-grass pasture with different heights. This study evaluated the influence of Tanzania-grass sward height 30, 50, 70 and 90 cm on the morphological characteristics of the canopy, grazing behavior and forage intake by adult Anglo Nubian female goats.
A completely randomized experimental design was employed, with two replicates in space and two replicates in time.
Six animals were used to assess the grazing behavior, and four, the ingestion process. The rise in sward height increased the forage and leaf mass, the percentages of stem and dead material, and reduced the leaf stem -1 ratio. Above 50 cm there was an increase in grazing time and a decrease in leisure time. A positive linear correlation was detected between sward height and bite depth. The consumed forage mass, ingestion rate and daily intake were higher at 50 cm, indicating that the other heights reduced the intake process.
The sward height was negatively correlated to the bite rate and positively to the bite time. The sward height of 50 cm presents the best combination of features, favoring the grazing and ingestive behavior of female adult goats. In this context, the use of technologies to reduce risk and increase productivity will contribute to change the current profile of goat farming in Brazilian Northeast, from the extractivism to an income-generating activity.
Panicum maximum stands out among improved species of tropical grasses introduced in the last two decades in Brazil, whose cultivars are among the main forage used, with high productivity and persistence under intensive management because of its high photosynthetic and hydric efficiency, besides its extensive phenotypic plasticity, depending on the frequency of defoliation POMPEU et al. In recent years, the Tanzania-grass Panicum maximum cv. Furthermore, the canopy structure, especially in tropical forage, exerts direct effect on the process of ingestion and consumption of forage, by affecting the forage intake by the animal.
