Pistacia terebinthus as a dietary supplement for laying hens
The aim of this study was to explore the potential of Pistacia terebinthus (terebinth) seed meal as a dietary supplement for laying hens. One hundred and ninety-two Babcock 30-week-old laying hens were assigned to one of six treatments (n = 32) with four replicates (n = 8). The hens were fed diets containing 0%, 1%, 2%, 3%, 4%, and 5% terebinth seed meal for eight weeks. Weekly egg production, feed consumption, egg weight, and egg mass were recorded. Egg quality was assessed at the beginning, middle and end of the study. Blood sampling was carried out on 12 birds from each treatment. Total antioxidant capacity, total oxidant status and oxidative stress index were determined. Egg production was greater from hens fed 3% and 4% terebinth than those in the other treatments. Egg weight was increased by supplementation with 2% or more terebinth. Feed consumption, feed conversion ratio, eggshell breaking strength, yolk colour, Haugh units, concentrations of glucose, total cholesterol, high density lipoprotein, low density lipoprotein, alanine aminotransferase, aspartate aminotransferase, total protein, phosphorus and calcium in serum, and total antioxidant capacity, total oxidant status, and the oxidative stress index did not differ across treatments. It is concluded that dietary terebinth seed supplementation generated positive effects on egg production and egg weight without adverse effects on egg quality or the metabolism of the hen.
Keywords: antioxidant, egg production, egg quality, feed consumption, serum biochemistry