Effect of diet physical form on fattening performance of Lori-Bakhtiari male lambs

The study was conducted to examine the effects of physical form of ration on fattening performance of Lori- Bakhtiari male lambs. Thirty six healthy male lambs with 41. 2±3. 27 Kg body weight were randomly assigned to one of three experimental diets (n=12): traditional ration (as control treatment)، total mixed ration (as mixed treatment) and total mixed ration in form of block (block treatment). Lambs were randomly distributed into three dietary treatments with three replicates and four lambs in each replication based on completely randomized design. Total experimental period was 90 days. During a three month experiment، dry matter intake (DMI)، lamb live weight and weight gain were recorded and feed conversion ratio was calculated. Results showed that، final live weight and average daily gain were significantly (P<0. 01) affected by physical form of diet. The lambs fed block ration had higher average daily gain (219 gram/day) than lambs fed mixed ration (193 gram/day) and traditional ration (170 gram/day). Average feed intake in control، mixed and block treatments were 1،523، 1،644 and 1،714 gram/d/head respectively and difference between control and other treatments was statistically significant (P<0. 05). Feed conversion ratio at the end of fattening period was not significantly different between all treatments but in block treatment was better than others (8. 99، 8. 50 and 7. 84 in control، mixed ration and block treatments respectively). It was concluded that، if providing block of ingredients was possible at same area، using block in fattening period of Lori-Bakhtiari male lambs may increase fattening performance.