concentrate to forage ratio

This experiment was aimed to study the effect of Ferula assa foetida essential oil or Artemisia aucheri essential oil in diets containing different concentrate ratios (40 and 60% of DM) on in vitro fermentation kinetic and acidosis induction. Essential oils were added at 0.05% of diet DM. Gas production parameters, pH, N-ammonia and volatile fatty acids (VFA) concentrations and total protozoa population were measured and organic matter digestibility (OMD) was estimated. The effect of Ferula assa foetida and Artemisia aucheriessential oils on prevention of in vitro acidosis induction was measured. The results showed that the interaction of diets and essential oils had no significant effect on in vitro gas production parameters, N-ammonia concentration, pH, total VFA, acetate, propionate and valerate concentrations, total protozoa population, Entodinium, Diplodinium,and Ophryoscolex population. The interaction of diets and essential oils on estimated OMD was significant (92.64 vs. 83.1 %, p < /em><0.05), and diet containing low concentrate level without essential oils had the lowest estimated OMD. Essential oils reduced gas production, total protozoa population and N-ammonia concentration (p < /em><0.05). Results of Ferula and Artemisia essential oils on prevention of in vitro acidosis induction showed that both essential oils prevent acidosis induction. It was concluded that Ferula and Artemisia essential oils improved rumen fermentation.

This experiment was conducted to investigate the effect of diet and fattening start weight on body growth in the different stages of the fattening periods and carcass compositions of Moghani male lambs. For this purpose, 36 heads of Moghani male lambs with three weights classes (Light, medium and heavy weight) were used with two diets (alfalfa to concentrate ratio of 70 to 30 (diet 1) and 30 to 70 (diet 2)) were fattening up to the time which their weights were 55 kg. The lambs were placed in individual cages for control the amount of feed daily intake and residual collected. The diets of high concentrate compared with diet of high forage were more favorable effect on body weight during the fattening at all stages and also daily weight gain (P<0.05). The significant difference was between heavy weight lambs (112 g/day) with light weight lambs (153 g/day) on daily weight gain (P<0.05). The diet had significant effect on carcass efficiency, hot and cold carcass weight, fat-tail weight and liver weight (P<0.05) and also percentage of fat-tail weight to carcass weight ratio (P<0.05). Negative correlation existed between fat-tail weight with different component of the carcass, especially with its valuable parts (leg, sirloin, breast and shoulder). Generally, high concentrate intake caused increase of fat-tail stores. Fattening with low weight increased daily weight gain, but in higher age was associated with fat stores in Moghani male lambs.