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【目的】 检验长期保存在国家家畜基因库的湖羊冷冻胚胎和冷冻精液的质量,评价超低温冷冻保存技术保种的效果。【方法】 对保存于国家家畜基因库的冷冻胚胎(保存20年)和冷冻精液(保存20和30年)进行复苏,进行相应鉴定后分别进行胚胎移植和人工授精,同时以0年冷冻精液和新鲜精液为对照,测定其受胎率和后代的羔皮性能、生长性能及繁殖性能,检验保存效果。【结果】 本试验共解冻胚胎36枚,其中,A级胚胎22枚,B级胚胎7枚,C级胚胎5枚,D级胚胎2枚,冷冻胚胎复苏利用率达到94.44%(34/36),A级胚胎率达到61.11%(22/36),移植34枚,产羔17只,冷冻胚胎复苏移植产羔率达50.00%;保存30年的冷冻精液复苏后平均精子活力达35%,受胎率为58.57%,平均产羔1.90只;保存20年冷冻精液复苏后平均精子活力达31%,受胎率为53.66%,平均产羔1.95只;胚胎复苏移植羊、30和20年冷冻精液后代体型外貌鉴定均符合纯种湖羊特征,没有畸形个体;羔羊一级羔皮率分别是31.25%、42.03%和23.81%,保持了当年湖羊的羔皮特性;生长发育及繁殖性能与现有湖羊群体性能基本保持一致。【结论】 利用超低温冷冻技术长期保存湖羊冷冻胚胎和冷冻精液的方法是可行的,对地方品种保种具有重要意义。 相似文献
23.
AbstractAIM: To evaluate resistance to anthelmintics containing abamectin, levamisole, and oxfendazole (AB-LEV-OX), derquantal and abamectin (DEQ-AB), moxidectin, and monepantel in naturally acquired gastrointestinal nematodes present on a sheep farm.METHODS: Faecal nematode egg count reduction tests (FECRT) were carried out on lambs that were approximately 7 months-old and infected with naturally acquired nematodes. Lambs were randomly allocated to one of five groups (n=15 per group): treatment with 2?mg/kg derquantel and 0.2?mg/kg abamectin; 0.2?mg/kg abamectin, 8?mg/kg levamisole HCl and 4.5?mg/kg oxfendazole; 2.5?mg/kg monepantel; 0.2?mg/kg moxidectin, or no treatment. Post-treatment samples were collected 12 days later. Abomasa and small intestines were collected from two slaughtered lambs from each of the DEQ-AB, AB-LEV-OX, moxidectin and control groups 15 days after treatment, for nematode counting.RESULTS: The FECRT demonstrated that efficacy was 90.3 (95% CI=84.2–94.1)% for AB-LEV-OX, 54.5 (95% CI=28.4–71.1)% for moxidectin, 99.2 (95% CI=97.4–99.8)% for DEQ-AB and 100% for monepantel, across all genera. For Trichostrongylus spp. efficacy was 85.5% for AB-LEV-OX and 46.7% for moxidectin. Haemonchus spp. were fully susceptible to all treatments. Post-treatment nematode counts indicated that the resistant Trichostrongylus spp. were from the small intestine.CONCLUSIONS: Anthelmintic resistance to both AB-LEV-OX and moxidectin was present in the Trichostrongylus genus on a commercial sheep farm. Monepantel and DEQ-AB were both effective against Trichostrongylus spp. based on FECRT results.CLINICAL RELEVANCE: This finding of resistance to an AB-LEV-OX triple-combination anthelmintic in the Trichostrongylus genus in sheep in New Zealand further limits anthelmintic treatment options available, and calls into question whether this combination is suitable for use as a quarantine treatment. 相似文献
24.
于工业氟污染区选取4只雌性氟斑牙小尾寒羊作为试验组,于氟安全区另选4只健康小尾寒羊作为对照组;分别采集其肋骨及牙齿,利用氟离子选择电极法测定了其骨氟及牙氟含量。结果表明,氟污染区小尾寒羊的骨骼和牙齿中氟含量均明显高于氟安全区,差异极显著(P<0.01);氟污染区骨氟含量较对照组相对增长了73.5%;试验组牙氟含量较对照组相对增长了161.6%;表明氟在牙齿中的蓄积程度高于骨骼。本试验为进一步研究氟中毒对牙齿和骨骼的损伤机理奠定基础。 相似文献
25.
为研究甘南地区欧拉羊杂交改良山谷型藏羊效果,对欧拉羊与山谷型藏羊杂交试验组和山谷型藏羊本交对照组所产后代的初生、3月龄、6月龄、12月龄、18月龄的体尺、体重进行了跟踪测定,并对不同年龄段杂交后代与对照组后代进行了对比分析和差异显著性检验。结果表明:杂交F1代初生、3月龄、6月龄、12月龄、18月龄的体尺、体重极显著的高于对照组(P〈0.01),初生、18月龄管围差异显著,3月龄、6月龄、12月龄管围差异不显著(P〉0.05)。 相似文献
26.
本试验旨在获得中国美利奴羊成纤维细胞生长因子10(fibroblast growth factor 10,FGF10)基因的编码区(CDS)全长序列并进行生物信息学分析,随后对FGF10基因在中国美利奴羊毛囊发育过程中的表达特征进行分析,明确其在中国美利奴羊毛囊发育过程中的表达模式,为进一步研究FGF10 mRNA表达水平与中国美利奴羊毛囊生长发育的表达调控机制奠定理论基础。采用PCR扩增获得中国美利奴羊FGF10基因CDS,并克隆到zero PCR@TM-Blunt进行测序验证;利用实时荧光定量PCR技术检测FGF10在中国美利奴羊毛囊发育过程中的表达差异。结果表明,绵羊FGF10基因CDS长度为696 bp(序列上传GenBank,获得登录号:MT872422),编码231个氨基酸,与牛和山羊的氨基酸序列同源性达100%,存在1个信号肽和1个跨膜结构域,其为分泌通路信号蛋白;实时荧光定量PCR分析表明,FGF10基因在中国美利奴羊毛囊发育过程中均表达,在毛囊发育第85天表达最高,显著高于其他毛囊发育时期(P<0.05)。本研究获得中国美利奴羊FGF10基因完整的编码区序列和毛囊发育过程中的表达特征,生物信息学分析发现,FGF10基因编码区序列具有物种间的保守性,同时FGF10在绵羊毛囊不同发育阶段的皮肤组织中表达,由此表明,FGF10基因可能在绵羊毛囊的生长发育过程中发挥重要的生物学作用。 相似文献
27.
《Communications in Soil Science and Plant Analysis》2012,43(22):2798-2806
Grazing modifies the aboveground soil and plants of rangeland ecosystems. This study was conducted to determine the effects of various grazing intensity levels on soil bulk density, soil pH, soil electrical conductivity (EC), soil total organic carbon (TOC), aboveground biomass production, plant community richness (N), and vegetation diversity (H) in Gian Rangeland, Hamedan Province, Iran. Soil and vegetation samplings were conducted based on the randomized systematic method. Soil and vegetation samplings were carried out along 100-m-long transects placed at 100, 200, 400, 800, and 1600 m running perpendicular to six sheep corrals. The effects of various grazing intensities on studied parameters were detected by analysis of variance (ANOVA) (at α = 0.05). Results of this study indicated the soil bulk density, EC, TOC, aboveground biomass production, plant community richness, and vegetation diversity values were altered significantly at different distances from the sheep corrals. However, soil pH was not significantly affected by various grazing intensities. 相似文献
28.
29.
Elsheikh HA Taha AA Khalafalla AE Osman IA Wasfi IA 《Veterinary research communications》1999,23(8):507-514
The pharmacokinetics of amoxicillin were studied in five Desert sheep and five Nubian goats after intravenous (i.v.) or intramuscular (i.m.) administration of a single dose of 10 mg/kg body weight. Following i.v. injection, the plasma concentration-versus-time data were best described by a two-compartment open model. The kinetic variables were similar in both species except for the volume of the central compartment (Vc), which was larger in sheep (p<0.05). Following i.m. injection, except for the longer half-life time of absorption in goats (p<0.05), there were no significant differences in other pharmacokinetic parameters between sheep and goats. The route of amoxicillin administration had no significant effect on the terminal elimination half-life in either species. The bioavailability of the drug (F) after i.m. administration was high (>0.90) in both species. These results indicate that the pharmacokinetics of amoxicillin did not differ between sheep and goats; furthermore, because of the high availability and short half-life of absorption, the i.m. route gives similar results to the i.v. route. Therefore, identical intramuscular and intravenous dose regimens should be applicable to both species. 相似文献
30.
A. Nurfeta 《Journal of animal physiology and animal nutrition》2010,94(6):773-779
The aim of this study was to investigate the effects of different levels of Desmodium intortum (Desmodium) hay supplementation in sheep fed fixed amounts of enset pseudostem or corm and a basal diet of wheat straw on intake, digestibility and nitrogen utilization. Eighteen male sheep with a mean (± SD) live weight of 20.5 ± 1.45 kg were assigned to six treatments in a completely randomized design and fed either 108 g dry matter (DM) enset pseudostem or 165 g DM enset corm each with three levels (100, 200 and 300 g) of hay supplementation. For the pseudostem diets, there was no significant difference in total DM intake. Total crude protein (CP) intake and N retention increased with increasing levels of hay in both pseudostem and corm diets. The apparent digestibility of DM, OM, CP, acid detergent fibre and neutral detergent fibre (NDF) and microbial nitrogen supply (MN) at 100 g was lower that other levels of supplementation. For the corm diets, total DM and OM intake and MN supply increased with increasing levels of hay. The digestibility decreased (p < 0.001) with increasing levels of supplementation. The results suggest that at least 300 g (395 g/kg dietary DM) of Desmodium hay is required in pseudostem diets, whereas 200 g (337 g/kg dietary DM) may be sufficient in corm diets for efficient nutrient utilization. 相似文献