Khadem A A, Pahlavan M, Afzalzadeh A, Rezaeian M
Department of Animal Science, Abourayhan Institute, University of Tehran, P.O. Box 11365-4117, Tehran, Iran.
Pak J Biol Sci. 2007 Feb 15;10(4):590-7. doi: 10.3923/pjbs.2007.590.597.
The effects of live yeast Saccharomyces cerevisiae (LYSC, strain Sc 47) on rumen fermentation and microbial populations, digestibility of nutrients, degradability of alfalfa hay and on the performances of sheep were investigated in two experiments. In both experiments, animals in treatment groups were received 0, 2.5, 5 and 7.5 g of LYSC per sheep per day and were defined as control, 2.5, 5.0 and 7.5 g LYSC treatment groups, respectively. In the first experiment, four fistulated Chall sheep (49 +/- 0.5 kg BW) were kept in individual metabolic crates under a 4x4 Latin square design and fed a Total Mixed Ration (TMR) containing of barely (48%), wheat bran (16%), shelled corn (5%), mineral-vitamin mix (1%) and of alfalfa hay (30%). In the second experiment, 28 sheep (48 +/- 0.5 kg BW) were assigned into four treatment groups under a complete randomized design and fed a TMR containing of barely (60%), wheat bran (7%), cottonseed meal (2%), mineral-vitamin mix (1%) and of alfalfa hay (15%) and wheat straw (15%). The highest and the lowest ruminal pH values (p < 0.01) were recorded for sheep in 2.5 g LYSC and control groups, respectively. At 3 h post-feeding, the total VFA of rumen fluid was increased (p < 0.01) from 91.26 to 103.34 mmol L(-1) in control vs. 2.5 g LYSC groups. The ruminal NH3-N of sheep was decreased (p < 0.01) from 159.63 to 128.90 mg L(-1) in control vs. 2.5 g LYSC groups. Bacterial populations of rumen fluids were differed from 14 to 43% in treatment groups although the differences were not significant. Compared to the other groups, voluntary feed intake was higher (p < 0.01) in 5.0 g LYSC group and this was ended to an inappropriate feed to gain ratio in this group. It can be concluded that the use of LYSC at a level of 2.5 g per sheep per day could improve the ruminal fermentation and resulted in a relatively better performances in Chall sheep.
通过两个试验研究了活酵母酿酒酵母（LYSC，菌株Sc 47）对瘤胃发酵、微生物种群、养分消化率、苜蓿干草降解率以及绵羊生产性能的影响。在两个试验中，各处理组绵羊每天每只分别采食0、2.5、5和7.5 g LYSC，分别定义为对照组、2.5、5.0和7.5 g LYSC处理组。在第一个试验中，4只装有瘤胃瘘管的夏洛来羊（体重49±0.5 kg）按照4×4拉丁方设计饲养在个体代谢笼中，饲喂一种全混合日粮（TMR），其组成为大麦（48%）、麦麸（16%）、玉米粒（5%）、矿物质-维生素预混料（1%）和苜蓿干草（30%）。在第二个试验中，28只绵羊（体重48±0.5 kg）按照完全随机设计分为4个处理组，饲喂一种TMR，其组成为大麦（60%）、麦麸（7%）、棉籽粕（2%）、矿物质-维生素预混料（1%）、苜蓿干草（15%）和小麦秸秆（15%）。2.5 g LYSC组和对照组绵羊的瘤胃pH值分别为最高和最低（p<0.01）。采食后3 h，对照组瘤胃液总挥发性脂肪酸（VFA）从91.26 mmol L⁻¹增加到103.34 mmol L⁻¹，而2.5 g LYSC组增加（p<0.01）。对照组绵羊瘤胃氨态氮（NH₃-N）从159.63 mg L⁻¹降至128.90 mg L⁻¹，2.5 g LYSC组降低（p<0.01）。各处理组瘤胃液细菌数量差异为14%至43%，尽管差异不显著。与其他组相比，5.0 g LYSC组的自愿采食量较高（p<0.01），但该组饲料转化率不合适。可以得出结论，每天每只绵羊使用2.5 g LYSC可改善瘤胃发酵，并使夏洛来羊的生产性能相对更好。
