Inclusion of phytogenic blends in different nutrient density diets of meat-type ducks

A total of 160 1-day-old ducklings (average initial body weight of 53 g), were used in a 42-d feeding trial to evaluate the effects of reducing nutrient density of diets, and supplementing the diets with a phytogenic blend (quillaja, anise, and thyme) on their growth, carcass quality, and nutrient digestibility. After checking body weight on d 1, the birds were sorted into pens with 5 birds/pen and 8 pens/treatment. The treatments were: T1, Basal diet; T2, T1 + 150 ppm phytogenic blend; T3, T1 - (1% CP, 0.04% Lys, 0.05% Met+Cys, 0.02% Ca, and 0.02% P, and 50 kcal ME); T4, T3 + 150 ppm phytogenic blend. The results indicated that reducing nutrient density of the diets had an adverse effect (P < 0.05) on body weight gain (BWG) on d 1 to 21, d 21 to 42, and the overall experimental period. Supplementing the diets with the phytogenic blend improved (P < 0.05) BWG and feed conversion ratio (FCR) on d 21 to 42 and the overall experimental period. Feed intake was not affected by treatments. Low nutrient density diets increased (P < 0.05) the cooking loss percentage of breast meat. Supplementing the diets with the phytogenic blend decreased (P < 0.05) the lightness of breast meat. The percentage of drip loss was influenced (P < 0.05) by nutrient density and the phytogenic blend on d 1 and d 7. The relative weights of breast meat, abdominal fat, gizzard, liver, spleen, and bursa of Fabricius, pH, and TBARS values were not affected by the treatments. The digestibility of dry matter, energy, nitrogen, ADF, and NDF was decreased (P < 0.05) by reducing nutrients density of the diets, but addition of the phytogenic blend alleviated (P < 0.05) the negative effects of lowering the nutrient density. The results indicated that the ducks fed high nutrient density diets supplemented with the phytogenic blend showed higher BWG and nutrient digestibility and lower FCR, cooking loss, drip loss, and TBARS value, without any negative effect on meat quality and relative organs weights.