This study was carried out to determine the effects of supplementing different levels (0, 0.5 and 1% of buffered rumen fluid) of methanolic extract of pomegranate peel, on rumen fermentation kinetics of four oil seed meals (soybean meal, cotton seed meal, rapeseed meal and sunflower seed meal), using in vitro gas production technique. The samples were incubated in syringes containing rumen liquor taken from three fistulated Iranian Ghezel rams for 2, 4, 6, 8, 12, 24 and 36 h. Results showed that, addition of methanolic extract of pomegranate peel led to significant increase in gas production volume in all incubation times and all of oil seed meals as well. Amount of gas production, also increased by increasing dose of the extract. Also, amounts of a (the gas production from the immediately soluble fraction), b (the gas production from the insoluble fraction) and a + b (the potential gas production) in all of tested oil seed meals increased by increasing pomegranate peel extract doses. Adding pomegranate peel extract resulted in increase volatile fatty acids (VFA) production. Production of VFA increased significantly by the level of the extract supplementation. In conclusion, it is suggested that, adding methanolic extract of pomegranate peel can be lead to higher ruminal fermentation and VFA production in ruminants. Manuscript profile

The present study was conducted to investigate the possibility of using a modified in vitro gas production technique in place of the nylon bag method to estimate protein degradability of alfalfa hay in ruminants. In the in situ experiment dacron bags were filled with 3 g alfalfa hay. This was incubated in the rumen of three ruminally cannulated Ghezel rams for the periods of 0, 2, 4, 8, 12, 16, 24, 36 and 48 h. At the end of the experiment, dry matter, organic matter and crude protein degradability (CPD) were calculated. In the in vitro experiment, buffered rumen fluid was prepared in a solution of 19:1 artificial saliva to rumen fluid, which was pre-incubated by rapidly fermentable carbohydrates for 4 h. After pre-incubation, 30 mL of the buffered rumen fluid were added to 100 mL syringes, containing the alfalfa sample, with 7.5 mg N. The samples were incubated for 2, 4, 6, 8, 12, 16, 24, 36, 48, 60 and 72 hours, after which net gas production was computed. In the third experiment, 25 grams of faeces were mixed with 50 mL of artificial saliva, which was then made up to 1 liter by adding more artificial saliva and filtered. Then, the suspension was pre-incubated for 4 h. After pre-incubation, the same steps used to measure gas production were conducted. Results showed that there were significant differences between gas production with rumen liquor and faeces suspension at 2, 4, 24, 36 and 48 h of incubation, while no significant differences were found at other incubation times. There was a close relationship between crude protein degradation at different times and amount of gas production using rumen liquor [CPD= 58.93 + 0.32 gas (r2=0.76, n=18)] and fecal suspension [CPD= 58.38 + 0.27 gas (r2=0.60, n=18)]. The results indicated that faeces suspension can be used instead of rumen liquor as the medium in the gas production method. Development of the gas production technique could result in reducing the need to use fistulated animals in feed evaluation studies. Manuscript profile