Evaluation of Nutritional Value and Ruminal Fermentation of Mesquitepod

Mesquite is the dominant flora of southern Iran. Whole pod contains capsule and some seeds which its color, after ripen, is yellow and contains considerable protein and carbohydrate. One of the most important usage of this pod is as animal feed, because the ripen pod is palatable and has high nutritional value. This study was conducted to evaluate chemical composition, ruminal fermentation and digestibility of different parts of mesquite plant as a completely randomized design.
Mesquite pod was collected from different areas of Hormozgan province. Whole pod, husk and seed were grounded separately. Chemical composition of different parts of mesquite pod (dry matter, organic matter, ash, ether extract, crude protein, non fiber carbohydrate, neutral detergent fiber, acid detergent fiber and lignin) was separately determined. In vitro gas production test (IVGPT) was conducted at two parts. For this purpose, rumen fluid was obtained from three fistulated rams before the morning feeding. The rams were fed twice daily with a diet containing alfalfa hay and commercial concentrate to meet their requirements. The collected ruminal fluid was pooled in a flask and was transported under anaerobic conditions to the laboratory. Rumen fluid was filtered through four layers cheesecloth and then mixed continuously with CO2 and maintained at 39 o C before the usage. After pre-incubation, the rumen fluid was mixed with buffered mineral solution at the ratio of 1:2 rumen fluid to mineral buffer (V/V). At first part of IVGPT to evaluate kinetics of ruminal fermentation at different incubation time (120 hours), 200 mg of dried and grounded sample was transfer to glass syringe. Syringes were filled with 30 ml of medium (consisting of 10 ml of rumen fluid and 20 ml of buffer solution). The values of produced gas at 0, 2, 4, 6, 8, 12, 24, 48, 72, 96 and 120 hours after incubation time were determined. At second part of IVGPT, 500 mg sample with 40 ml medium incubated for 24 hour and amount of produced gas, apparent dry matter digestibility, true organic matter digestibility and partitioning factor of samples were measured. Total gas production of each syringe (at first and second parts of IVGPT) was corrected for blank which contained only rumen fluid. Two stages in vitro digestibility was done. Different parts of protein in whole pod and husk were estimated based on CNCPS method.
Results showed that there were significant differences for chemical compositions of different parts of mesquite pod except for dry matter (DM) and acid detergent fiber (P