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271.
0~2周龄肉用雏鸡卵黄囊等组织中蛋氨酸、胱氨酸含量的变化规律 总被引:2,自引:0,他引:2
本试验旨在探讨0~2周龄肉用雏鸡如何从内源(卵黄囊)营养转变为外源(饲料)营养,以及外源蛋氨酸(Met)和胱氨酸(Cys)营养水平与体组织内该两种氨基酸营养的相关性。试验用600只爱拔益加(AA)鸡,平均为10个处理组,每组设3个重复。在0~2周龄雏鸡日粮中,分别添加0.20%、0.25%、0.30%、0.40%和0.80%的DL—蛋氨酸,以及0.15%、0.20%、0.30%和0.40%的 DL—胱氨酸,观察1,3,5,7,14日龄雏鸡体内卵黄囊、肝脏和血浆等组织中相应氨基酸的变化规律。结果表明,0~2周龄雏鸡的营养特点是,1~3日龄的营养完全来自于卵黄囊,5~7日龄是卵黄囊营养转变为饲料营养的过渡期,8~14日龄的营养已完全来自饲料;1~7日龄期间,雏鸡的卵黄囊、血浆和肝脏中的蛋氨酸含量不受日粮中蛋氨酸水平的影响;但14日龄时,血浆和肝脏中的蛋氨酸含量随日粮蛋氨酸水平的提高呈上升趋势。这一结果证明蛋氨酸(第一限制性氨基酸)营养对0~2周龄雏鸡的重要性。由于胱氨酸不是限制性氨基酸,故雏鸡对它在日粮中的变化不敏感,在雏鸡组织中的含量也未见有规律性的变化。 相似文献
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D. RUGG D. THOMPSON RP GOGOLEWSKI GR ALLERTON RA BARRICK JS EAGLESON 《Australian veterinary journal》1998,76(5):350-354
Objective To investigate the efficacy of ivermectin in an intraruminal controlled-release capsule (CRC) against blowfly strike.
Design Pen and field trials with controls.
Animals Pen studies: Two breech strike trials involving 60 Romney and 60 Merino sheep. One body strike trial using 100 Merino sheep.
Field trials: Eight trials in New Zealand used 1000 Romney and Romney-cross sheep. Fifty Merino lambs in one trial in Australia.
Procedure Pen studies: Sheep were allocated to two equal groups. One was not treated, the other sheep received a CRC that delivered ivermectin at 20 μg/kg/day for 100 days. In the breech strike trials, each animal was given an oral laxative 2 days before exposure to adult Lucilia cuprina . In the body-strike trial, the sheep sheep were kept wet to increase susceptibility prior to the release of blowflies.
Field trials: Fifty or 200 sheep allocated to equal groups of nontreated or treated with the CRC and grazed at pasture exposed to natural blowfly challenge.
Results Pen studies: Breech strikes developed in 24 of 60 controls but in none of 60 CRC-treated sheep. There was a 35% reduction in the number of CRC-treated sheep struck on the body.
Field trials: The average number of breech strikes in CRC-treated sheep was reduced by 86% (P < 0.001). The number of body strikes in the treated groups was a reduced by 27% (P < 0.05).
Conclusion The ivermectin CRC is a useful aid in controlling breech strike, but provides only moderate reduction in the incidence of body strike. 相似文献
Design Pen and field trials with controls.
Animals Pen studies: Two breech strike trials involving 60 Romney and 60 Merino sheep. One body strike trial using 100 Merino sheep.
Field trials: Eight trials in New Zealand used 1000 Romney and Romney-cross sheep. Fifty Merino lambs in one trial in Australia.
Procedure Pen studies: Sheep were allocated to two equal groups. One was not treated, the other sheep received a CRC that delivered ivermectin at 20 μg/kg/day for 100 days. In the breech strike trials, each animal was given an oral laxative 2 days before exposure to adult Lucilia cuprina . In the body-strike trial, the sheep sheep were kept wet to increase susceptibility prior to the release of blowflies.
Field trials: Fifty or 200 sheep allocated to equal groups of nontreated or treated with the CRC and grazed at pasture exposed to natural blowfly challenge.
Results Pen studies: Breech strikes developed in 24 of 60 controls but in none of 60 CRC-treated sheep. There was a 35% reduction in the number of CRC-treated sheep struck on the body.
Field trials: The average number of breech strikes in CRC-treated sheep was reduced by 86% (P < 0.001). The number of body strikes in the treated groups was a reduced by 27% (P < 0.05).
Conclusion The ivermectin CRC is a useful aid in controlling breech strike, but provides only moderate reduction in the incidence of body strike. 相似文献
275.
GR ALLERTON RP GOGOLEWSKI D. RUGG RE PLUE RA BARRICK JS EAGLESON 《Australian veterinary journal》1998,76(1):39-43
Objective To confirm the efficacy of ivermectin released from a controlled-release capsule administered to young sheep and to breeding ewes under field conditions. Design Randomised field trials. Procedure In each of ten field trials 25 weaned lambs were treated with ivermectin controlled-release capsules and 25 remained untreated. Eight similar field trials were conducted using adult ewes. Efficacy against infections of gastrointestinal nematodes was assessed by faecal egg counts and faecal larval culture. Body weights were recorded and faecal soiling of the breech wool (dags) was assessed. Results Nematode faecal egg counts in the two groups were not different (P = 0.13) before treatment in the weaner trials or before treatment in the ewe trials (P = 0.49), but thereafter eggs in the untreated sheep persisted, whereas counts in sheep given capsules were negligible (P ≤ 0.01). In the weaner trials, dag scores for the two groups were not different at the start of the trials (P = 0.18) but at the end, untreated sheep had significantly more dags (P = 0.04) than treated sheep. In the ewe trials, dag scores remained low in both groups. Weaners treated with the capsule gained 1.4 kg (95% CL: 0.7, 3.1) more weight over the 16 week trial period compared to untreated weaners (P = 0.01). Both groups of ewes lost weight as a result of parturition but the mean loss by week 16 was greater for untreated (3.7 kg) (95% CL: -5.1,-2.2) than for treated ewes (1.8 kg) (95% CL: -3.3, -0.4). The mean change in ewe body weight for the two groups was however not significant (P = 0.07). Differentiation of nematode larvae recovered from cultures of faeces from untreated animals indicated that the capsules were effective against the common parasites of sheep. Conclusion The capsule was efficacious against gastrointestinal nematodes judging from faecal egg counts. It has the potential to significantly reduce contamination of pasture with nematode eggs. Treated weaners had less dags for 16 weeks and gained more weight than untreated weaners. 相似文献
276.
【目的】研究复方中药超微粉对蛋鸡产蛋性能、生殖激素及相关基因表达的影响。【方法】试验选取307日龄的新杨黑羽蛋鸡216只,随机分为3组,每组8个重复,每个重复9只;对照组饲喂基础饲粮,试验组分别在基础饲粮中添加0.5%丹参Salvia miltiorrhiza+0.25%女贞子Ligustrum lucidum+0.25%蒲公英Taraxacum mongolicum(复方1)、0.3%益母草Leonurus japonicus+0.2%丹参+0.25%女贞子+0.25%蒲公英(复方2)的超微粉,均以质量分数计;预试期7 d,正试期120 d。测定产蛋性能、蛋品质、血浆生殖激素水平,用RT-PCR技术检测蛋品质相关基因表达。【结果】与对照组相比,试验1~30、31~60和1~120 d,复方1组产蛋率分别增加7.56%、4.00%和5.31%(P<0.05);试验1~120 d,复方2组产蛋率增加5.22%(P<0.05);试验第60天,复方1组血浆雌二醇水平、输卵管PMCA1的mRNA相对表达量分别增加21.45%和77.00%(P <0.05),复方2组输卵管KC... 相似文献
277.
超微粉碎处理对葡萄籽中原花青素和脂肪酸成分的影响 总被引:3,自引:0,他引:3
旨在通过超微粉碎处理对葡萄籽主要营养成分的影响研究,确定该技术在葡萄皮渣精深加工中的适用性。试验以酿酒后皮渣中分离获得的葡萄籽为材料,采用超微粉碎技术对葡萄籽进行超微粉碎处理,重点研究超微粉碎工艺对葡萄籽粒径、原花青素的含量、脂肪酸成分的影响。结果表明,与普通粉碎葡萄籽粉对比,经超微粉碎处理后葡萄籽粉中的原花青素含量达到8.74mg/g以上,其增加了28.5%,而超微粉碎处理对葡萄籽粉中不饱和脂肪酸的影响较小,保留率较高。实验证明,不同超微粉碎时间(5~25 min)处理对超微葡萄籽粉中的原花青素和脂肪酸含量无显著影响。结果证明超微粉碎处理有利于葡萄籽中原花青素的释放和不饱和脂肪酸的保留,适宜在葡萄皮渣精深加工中推广应用。 相似文献
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279.
Fang Yang Fangyuan Hu Qixing Jiang Yanshun Xu 《Journal Of Aquatic Food Product Technology》2013,22(6):916-927
ABSTRACTEffect of pretreatment methods including ultrasonication (US), microwave (MW), and ultrafine milling (UM) on hydrolysis efficiency and antioxidative activity of peptides produced from bighead carp were investigated. The UM peptides showed higher hydrolysis efficiency (higher degree of hydrolysis, nitrogen recovery, and oligopeptide yield; narrower molecular-weight distribution), and higher 1,1-dipheny1-2-pycrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfomic acid) diammonium salt (ABTS) radical scavenging activities, and metal chelating activities than US and MW peptides. The hydrolysis efficiency and antioxidative activity of UM peptides could remain relatively high even when the substrate concentration increased up to 50%. In conclusion, ultrafine milling may be a suitable pretreatment method in the production of peptides. 相似文献
280.
12种药剂对蛴螬的田间药效评价 总被引:4,自引:0,他引:4
为有效控制花生蛴螬危害,筛选高效、低毒、低残留的农药品种,选用12种不同杀虫剂,采用毒土处理方法进行田间药效试验。试验结果表明,供试的12种药剂中,30%辛硫磷微囊悬浮剂4050 g/hm2、30%毒死蜱微囊悬浮剂2250 g/hm2,对蛴螬防治效果分别为80.85%、78.73%,与3%克百威颗粒剂135 g/hm2、10%二嗪磷颗粒剂750 g/hm2差异不显著,但显著高于其它药剂,其对花生的保果效果分别为81.45%、80.99%,增产幅度分别为15.74%、12.71%,可作为替代高毒产品的理想药剂。 相似文献