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1.
本文用180只肉仔鸡,进行饲养试验,研究黑麦日粮添加4种不同酶制剂,NQ、RM1、RM2和RM3,对肉仔鸡的生产性能以及肠道食糜及泄殖腔粪样粘度的影响。酶制剂NQ和RM1含有高的木聚糖酶活(7700IU/g,3450IU/g)能极显著改进(P<0.01)增重(8.4%,16.0%)和饲料转化率(15.4%,14.4%),RM2,含有相对低的木聚糖酶(60IU/g)和相对高的阿拉伯呋喃糖苷酶活(5.3IU/g),产生类似的效果(P<0.01):增重提高10.5%,饲料转化率提高11.8%,然而RM3,由于含木聚糖酶活较低(5IU/g)和较高的蛋白酶活(80IU/g),则对增重无效,但亦可改善饲料转化率(6.4%,P<0.05)。上述酶制剂在降低肠道食糜和泄殖腔粪样粘度方面与增重和饲料转化率有相同的趋势。一般说来,日粮中添加的酶量与食糜相应的粘度成倒数关系。这些结果证明:具有较高木聚糖酶活的酶制剂能明显降低肠道食糜和泄殖腔粪样的粘度,从而改善饲喂黑麦日粮肉仔鸡的生产性能。  相似文献   
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The influence of the level of magnesium (Mg) in the ration on reproduction by the hen was studied in 2 experiments. In experiment 1, it was found that feeding a semi‐purified ration, containing 56 p.p.m. of Mg, resulted in decreased egg production and reduced serum Mg concentration within 10 to 14 days. Although fertility of eggs was not affected noticeably by Mg deficiency, hatchability of fertile eggs was decreased markedly. The influence of inadequate dietary Mg was partially alleviated by adding 250 p.p.m. Mg to the ration. In experiment 2, a decline in hatchability preceded decreases in egg production and food consumption. A decrease in Mg concentration in egg contents accompanied the decline in hatchability. Hens fed rations containing 50 or 150 p.p.m. added Mg produced eggs of relatively low hatchability by day 14 of the trial. Subsequent to being fed a ration containing 550 p.p.m. added Mg, these hens increased in rate of egg production while hatchability of fertile eggs also increased. The results indicate that the dietary Mg requirement of the laying hen, sufficient to maintain a high rate of production of eggs which hatch satisfactorily, is 400 or more p.p.m.  相似文献   
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An experiment was done to determine manure output, N and P excretion, and apparent digestibilities of AA, CP, P, and DM in growing pigs fed barley-based diets containing micronized or raw peas with or without supplementation with enzyme containing primarily beta-glucanase and phytase (Biogal S+). Eight barrows (21.5 +/- 1.2 kg of initial BW) fitted with T-cannulas at the distal ileum were used in a 40-d trial and housed in metabolism cages. Pigs were assigned in a replicated 4 x 4 Latin square design to 4 experimental diets: 1) barley-raw peas control (BRP), 2) barley-micronized peas (BMP), 3) BRP plus enzyme, and 4) BMP plus enzyme (BMP+E). Pigs received 2.6 times maintenance energy requirements based on BW at the beginning of each experimental period. During each experimental period, pigs were acclimatized to their respective diets for 5 d followed by a 3-d period of total fecal and urine collection and another 2-d period of ileal digesta collection. Samples were analyzed for DM, AA (diets and digesta only), N, and P. Wet fecal output of BRP plus enzyme-fed pigs tended to be lower (P = 0.07) than the amount produced by BMP-fed pigs. The amounts of dry feces and urine produced were not different among treatments (P > 0.10). Supplementing the BRP and BMP diet with enzyme increased (P = 0.002) the daily P retained per pig. Pigs fed the enzyme-supplemented diets tended to have lower (P = 0.06) fecal P excretion and greater urinary P excretion (P = 0.001) compared with pigs fed the nonsupplemented diets, but total P excretion was not influenced by diet (P > 0.10). Pigs fed the BMP+E diet retained more (P = 0.006) N per day than pigs fed the BMP diet. However, N excretion was not influenced by dietary treatment (P > 0.10), although BMP+E-fed pigs excreted 13.2% less N in the feces compared with those fed the nonenzyme supplemented controls. Inclusion of micronized peas with or without enzyme supplementation did not affect urinary or fecal N excretion (P > 0.10) compared with the BRP. Dietary treatment had no effect (P > 0.10) on ileal or fecal DM or CP digestibilities. Apparent ileal digestibilities of AA were usually lower (P < 0.05) in the BRP diet compared with the other diets. Enzyme supplementation improved P digestibility at the ileal and fecal level. The current results indicate that utilizing micronized peas in barley-based pig grower diets enhances P retention.  相似文献   
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Fat tissue is the most important energy depot in vertebrates. The release of free fatty acids (FFAs) from stored fat requires the enzymatic activity of lipases. We showed that genetic inactivation of adipose triglyceride lipase (ATGL) in mice increases adipose mass and leads to triacylglycerol deposition in multiple tissues. ATGL-deficient mice accumulated large amounts of lipid in the heart, causing cardiac dysfunction and premature death. Defective cold adaptation indicated that the enzyme provides FFAs to fuel thermogenesis. The reduced availability of ATGL-derived FFAs leads to increased glucose use, increased glucose tolerance, and increased insulin sensitivity. These results indicate that ATGL is rate limiting in the catabolism of cellular fat depots and plays an important role in energy homeostasis.  相似文献   
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According to studies, latent Toxoplasma gondii infection may affect several functions of the human brain. Here we search for the association between latent toxoplasmosis and cognitive performance. We tested 70 individuals for latent T. gondii infection. There were 26 Toxoplasma-infected subjects and 44 Toxoplasma-free subjects. Within these two groups we assessed cognitive performance using a set of standardized, widely recognized neuropsychological tests: Trail Making Test, Stroop Test, Verbal Fluency Test, Digit Span Test and N-back test. The relationship between chronic toxoplasmosis and cognitive performance was assessed, with adjustment for age and sex. Patients with latent toxoplasmosis performed worse on one neuropsychological test, N-back Test--percentage of correct answers (beta -8.08; 95% CI - 15.64 to -0.53; p < 0.05) compared to seronegative patients. However, after adjustment for age and sex, no statistically significant associations between latent toxoplasmosis and the scores on any cognitive tests were noticed. As statistically significant relationship was not observed, this study does not confirm that chronic latent T. gondii infection affects cognition.  相似文献   
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对 2个不同加工方式生产的中国“双低”菜粕A和B以及 1个加拿大卡诺拉菜粕进行了体外消化和肉鸡饲养及代谢试验 ,以评价其营养价值。体外消化试验结果表明 ,卡诺拉菜粕、样品A和样品B的可消化蛋白质含量分别为 73 .6%、59.0 %和 51 .0 %(P <0 .0 1 ) ;2周的肉鸡生长试验表明 ,试验各期生长速度、采食量和饲料转化率差异显著 (P <0 .0 5)或极显著 (P <0 .0 1 ) ;代谢试验结果表明氮沉积率组间差异显著 (P <0 .0 5)。过热处理时 ,与中性洗涤纤维相连的蛋白质消化率降低 (P <0 .0 1 ) ,是导致氮沉积率低和肉鸡生长性能差的直接原因。试验结果也表明 ,过热处理或热处理不足 ,都对“双低”菜籽饼粕质量产生严重影响。  相似文献   
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系统地评价了 3个中国双低油菜与加拿大卡诺拉的商品饼粕与脱脂种籽的蛋白质、氨基酸、蔗糖、寡聚糖、饲粮总纤维和灰分等化学特性 ,并对饲粮总纤维的构成成分及加工的影响进行了研究。饲粮总纤维由非淀粉多糖、木质素和多酚、细胞壁蛋白质和矿物质组成。 3个中国双低菜粕的粗蛋白、蔗糖及必需氨基酸含量均接近或高于卡诺拉帕 ,但饲粮总纤维含量显著不同 ,尤其是蛋白质含量由于加工方式不同变异极大。在试验室条件下加工的脱脂种籽样品与相应的饼粕样品相比 ,蔗糖、赖氨酸和饲粮纤维含量变化显著。因此 ,改进双低油菜的加工技术是提高饼粕质量的关键  相似文献   
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