Native forages asessment for the improvement of milk production in goats

Abstract

The study was made in two parts. In the first, the food value was determined for two native Canarian species, Tagasaste (Chamaecytisus proliferus sp. proliferus var. palmensis) and common Tedera hay (Bituminaria bituminosa), well adapted to the climate. The chemical composition and digestibility were determined and the energy value for goats was estimated. The second phase of the experiment analysed the effects of the food on the milk production and quality when two different diets were fed. A common base of concentrates was used for the two groups of 20 Palmeran goats. The first diet, the Palmera Diet (PD) had a fibre content made up from the two native Canarian forages, whereas the other diet (Actual Diet or AD) was complemented with cereal straw. The quality and quantity of milk produced was recorded for 105 days, including in the middle part of lactation. The tagasaste was composed of 40% Dry Matter (DM) and 18% Crude Protein (CP), with Crude Protein Digestibility (CPD) reaching 75%, which represents 135g kg(-1) DM. The daily intake was 0.67 kg DM/animal, corresponding with 44 g DM kg(-1)P(0.75), with a considerably high energy value (9.18 MJ kg(-1) DM of Metabolizable Energy (ME). The tedera hay showed 87% DM and 15% CP, giving 105 g DPIN and 96g DPIE (Digestible Protein in the Intestine (DPI)). The Digestibility of the Dry Matter (DMD), Organic Matter (OMD) and Crude Protein (CPD) obtained in the metabolic cages was 60, 61.6 and 51.4%, respectively. The daily intake was 0.54 kg DM/animal, which corresponds with 3 1 g DM kg(-1) W-0.75, with a ME content estimated to be 7.9 MJ kg(-1)DM. Throughout the experiment the goats in the Palmera Diet (PD) group showed higher daily production values than the Actual Diet (AD) group. This peaked at 60 days when the average daily production was 26% greater in the PD than in the AD, diminishing to a difference of 15% at the end of the experiment. The fat and protein values were also better in the DP diet throughout the controlled time (representing up to 2.27 more fat and 1.01 kg more protein).