ABSTRACT
This work aimed to investigate the effect of sunflower oil supplementation with or without Thyme leaves (Thymus vulgaris) in lactating goat's rations on digestibility, milk yield, milk composition and milk fatty acid profile. Eighteen Zaribi goats of round 43 kg live body weight were divided into three similar groups (6 each) for the feeding trial that lasted 90 days. Three experimental rations were formulated, first control (T1) consisted of concentrate feed mixture (CFM) and berseem hay (1:1), second (T2) fed as T1 but supplemented at rate 3% of the total ration with sunflower oil (SO) and third one (T3) was fed as T2 but, supplemented with thyme leaves (Thymus vulgaris, THY) at rate 25 g/h/d.
Results showed that most digestibility of nutrients were significantly higher for T3 followed by T2 compared to the control (T1). However, to lesser extent CF digestibility was occurred with diet supplemented either with SO or SO+THY than the control. There was significant (P>0.05) increase in TDN value of T3, being 68.35% compared to control (66.39%). The control diet (T1) recorded the highest value of total saturated fatty acid, being 41.54%, while ration (T3) had the highest value of unsaturated fatty acid, being 35.47%. Supplementation with SO alone (T2) or with THY (T3) resulted in higher milk yield compared with control.
In conclusion, results showed that supplementation with sunflower oil and Thyme leaves to lactating goat's rations could increase milk yield and content of unsaturated fatty acids and decrease the saturated fatty acid in milk without any adverse effect on goats' health or lactation performance.