Samira Moradi - Department of Animal Science, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, Gonbad Kavous, Iran.
Farzad Ghanbari - Department of Animal Science, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, Gonbad Kavous, Iran.
Javad Bayat Kohsar - Department of Animal Science, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, Gonbad Kavous, Iran.
Mohsen Samiee Zafarghandi - Department of Animal and Poultry Nutrition, Faculty of Animal Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.

This research was conducted to evaluate the nutritional value of different varieties of barley (Turkmen, Reyhan and Gorgan), triticale (Juvanilo, Rondo and Massa) and oat (Wild and Canadian) grains. The chemical composition of the samples was determined using the standard methods of AOAC. Gas production (GP) test was performed to estimate the in vitro fermentation parameters. In vitro digestibility was determined by the batch culture procedure. The carbohydrate fractions of the Cornell Net Carbohydrate and Protein System (CNCPS) were also measured. Crude protein (CP) content was more in triticale and barley than oat grains (P<۰.۰۱). Triticale grains had higher contents of neutral detergent fiber (NDF), acid detergent fiber (ADF), and lower lignin compared to barley and oat grains (P<۰.۰۱). The amounts of GP potential and fermentation parameters were higher in triticale and barley than oat grains (P<۰.۰۱). Partitioning factor (PF, P<۰.۰۱), microbial biomass (MB, P<۰.۰۵) and efficiency of microbial biomass (EMB P<۰.۰۱) were more in different varieties of triticale and barley than oat varieties. According to CNCPS, carbohydrate portions and total carbohydrate content in triticale and barley grains were higher than in oat grains (P<۰.۰۱). The highest and lowest contents of none- fiber carbohydrates (NFC), starch, and soluble sugars were observed in triticale and oat varieties, respectively. Totally, triticale and barley grains had a better nutritional value than oat grains. Triticale grains were as good as barley grains in most aspects, while being superior in some traits.

In vitro digestibility, fermentation parameters, CNCPS model, cereal grains