Effect of level of Acacia tortilis and Faidherbia albida pods supplementation on the milk quality of dual-purpose dairy cows fed grass hay-based diets

Abstract

The effect of different levels of ground Acacia tortilis and Faidherbia albida pods as protein supplements on milk yield, composition and odour was investigated. In experiment 1, different levels of A. tortilis in the concentrate were compared: high (2 kg DM pods, 1 kg DM maize bran), low (1 kg DM pods, 1 kg DM sunflower seed cake, 1 kg DM maize bran) and control (2 kg DM of sunflower seed cakes and 1 kg DM maize bran). In experiment 2, the same treatments with F. albida and with an additional treatment with 2 kg DM soaked pods and 1 kg DM maize bran were included. The ground pods were soaked for 24 h, and sun-dried before being included in the concentrate. Six and eight cows were included in a double 3×3 and 4×4 Latin square design for experiment 1 and 2, respectively. Experiment 1 lasted for 8 weeks, and experiment 2 lasted for 10 weeks. Cows in their second and greater lactations, weighing 219–330 kg, were penned and fed individually. All cows had grass hay ad libitum, and concentrates were fixed at 3 kg DM per day. Milk yield differed between treatments ( P<0.05), but milk components were similar between the treatments. An unpleasant odour was found in milk from the cows on the high level of A. tortilis, with a slight or no odour in the milk from those on F. albida. Inclusion of 1 kg DM of pods in the concentrate mixture was not found to affect milk odour.