Production Potential of a Natural Pasture Compared to a Wheat Pasture, Both Grazed by Lactating Goats under Mediterranean Climate Conditions
The aim of this study was to extend the grazing period using a wheat pasture that produced high quality forage, and to compare the productivity of natural and wheat pastures for grazing goats during a 3-year period (2003-2005) in a Mediterranean zone of Turkey. Twelve 3-4-year-old Saanen goats were allocated to each pasture (10 goats ha-1). Pastures were grazed for 2 months (May and June) in 2003 and for 3 months (April, May, and June) in 2004 and 2005. In the study, pasture yield and hay intake, crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) content of the hay, and milk yield and milk fat percentage were determined. Pasture yield was significantly affected by pasture type (P < 0.001) for each year and the wheat pasture (5.34-6.51 t ha-1) yielded approximately 3.5-fold more hay than the natural pasture (1.48-1.88 t ha-1). Goats in the wheat pasture consumed significantly more forage in 2003 (P = 0.015), 2004 (P < 0.001), and 2005 (P < 0.001). Average hay intake in the wheat pasture ranged between 2.32 ± 0.27 and 2.53 ± 0.27 kg d-1 in 2003, 1.42 ± 0.26 and 3.35 ± 0.26 kg d-1 in 2004, and 2.69 ± 0.25 and 3.33 ± 0.25 kg d-1 in 2005, whereas it ranged between 1.54 ± 0.27 and 1.95 ± 0.27 kg d-1 in 2003, 0.79 ± 0.26 and 1.79 ± 0.26 kg d-1 in 2004, and 0.81 ± 0.25 and 1.60 ± 0.25 kg d-1 in 2005 in the natural pasture. Most of the interactions between pasture type and grazing month were statistically significant in terms of the CP, NDF, and ADF content of the pasture samples. In the first months CP content of the hay in the wheat pasture was higher than in the natural pasture, whereas this was reversed, especially in June. In addition, NDF and ADF content were not similar to CP content. In general, daily milk yield of the goats grazed on the wheat pasture was higher than that of those grazed on the natural pasture throughout the study. Milk yield was consistent with hay intake and milk fat percentage was inversely related to milk yield during the study. It was concluded that the wheat pasture had better potential for supplying nutrients to lactating dairy goats than did the natural pasture in spring.
Pasture type, pasture yield, hay intake, milk yield, goat