Milk production and quality of dairy goats fed Sulla or Alfalfa based-diet

Abstract

Hedysarum flexuosum which is a forage legume with high production potential can contribute to increase the production and improve the quality of desirable fatty acids in ruminant products. Production, chemical composition and fatty acid profile of Beni Aouss goat milk were studied to evaluate the effect of substitution of Medicago sativa with the Hedysarum flexuosum L. (Sulla) based diet, harvested at the beginning of flowering. Two homogeneous groups of fourteen goats were used to out this experiment. The roughage distributed in both groups is made up of Sulla forage (Sulla group) and Medicago sativa (control group). The same concentrated feed is distributed to both groups of goats. Milk yield was determined weekly during the first three months of lactation and milk samples were collected every week. The incorporation of Sulla in goat’s diet had a significant and positive effect on milk production (+15%). No significant differences were observed for milk pH and acidity. Sulla group milk was characterized by slightly higher lactose content (5.23% vs. 5.13%, P < 0.05) and defatted solid content (10.31% vs. 10.12%, P < 0.05), while their protein and fat contents were not affected. Milk fatty acid profile revealed that the levels of unsaturated fatty acids and medium chain fatty acids were higher in the Sulla milk than in the alfalfa group. ω3 fatty acids (0.39% vs 0.21%), ω6-fatty acids (3.42% vs. 2.79%), polyunsaturated fatty acids (3.96% vs. 3.15%), unsaturated fatty acids (43.00% vs. 41.11%) and medium chain fatty acids (25.00% vs. 23.82%) were significantly more present in the Sulla milk. Sulla forage may be an interesting alternative in goat’s feeding for diversifying feed resources and improving milk production and quality.

Keywords

• chèvre (indigène)
• production laitière
• hedysarum flexuosum
• qualité du lait
• medicago sativa