Effect of thymol and carvacrol on nutrient digestibility in rams fed high or low concentrate diets
Summary
Published data on the effects of essential oils (EO) on in vivo nutrient digestibility in sheep are contradictory. In 2 experiments, the effect of thymol and carvacrol on nutrient digestibility was studied in sheep fed with high (70%) or low (52%) concentrate diets, using incomplete Latin Square designs. The essential oils were mixed with the concentrate portion of the diet at the rate of 0.0, 0.3, or 0.6 g per kg dry matter (DM) diet. Supplementation of thymol had no significant effect on digestibility of dry matter (DM), organic matter (OM), crude protein (CP) and acid detergent fiber (ADF). The main effect of thymol on neutral detergent fiber (NDF) and ether extract (EE) digestibility and on nitrogen balance (NB) was significant (P 0.80) between the two experiments. Carvacrol was kindly supplied by Khorraman Pharmaceutical Company (Lorestan Province, Iran).
Feeding and sample preparation for analysis
Diets were fed twice daily (morning and afternoon). Daily feed (about 2 kg DM) was adjusted based on the amount of orts in the morning; it was increased by 100 g if orts were ≤ 100 g, and decreased by 100 g whenever orts were ≥ 200 g. When all feed had been consumed, …show more content…
Ruminal fluid was filtered through four layers of cheesecloth and pH was measured using a digital pH-meter (Jenway Model 3510, Camlab, Cambridge, UK). For determination of ruminal NH3-N, 5 mL of strained ruminal fluid was immediately acidified with 1 mL of 25% (w/v) meta-phosphoric acid and frozen at –20°C. Nitrogen balance was calculated by subtracting nitrogen excreted in the feces and urine from total nitrogen
Summary
Published data on the effects of essential oils (EO) on in vivo nutrient digestibility in sheep are contradictory. In 2 experiments, the effect of thymol and carvacrol on nutrient digestibility was studied in sheep fed with high (70%) or low (52%) concentrate diets, using incomplete Latin Square designs. The essential oils were mixed with the concentrate portion of the diet at the rate of 0.0, 0.3, or 0.6 g per kg dry matter (DM) diet. Supplementation of thymol had no significant effect on digestibility of dry matter (DM), organic matter (OM), crude protein (CP) and acid detergent fiber (ADF). The main effect of thymol on neutral detergent fiber (NDF) and ether extract (EE) digestibility and on nitrogen balance (NB) was significant (P 0.80) between the two experiments. Carvacrol was kindly supplied by Khorraman Pharmaceutical Company (Lorestan Province, Iran).
Feeding and sample preparation for analysis
Diets were fed twice daily (morning and afternoon). Daily feed (about 2 kg DM) was adjusted based on the amount of orts in the morning; it was increased by 100 g if orts were ≤ 100 g, and decreased by 100 g whenever orts were ≥ 200 g. When all feed had been consumed, …show more content…
Ruminal fluid was filtered through four layers of cheesecloth and pH was measured using a digital pH-meter (Jenway Model 3510, Camlab, Cambridge, UK). For determination of ruminal NH3-N, 5 mL of strained ruminal fluid was immediately acidified with 1 mL of 25% (w/v) meta-phosphoric acid and frozen at –20°C. Nitrogen balance was calculated by subtracting nitrogen excreted in the feces and urine from total nitrogen