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11.
A 13‐year‐old Romanov sheep presented for evaluation of vaginal discharge, depression and anorexia. Blood work demonstrated mature neutrophilia and marked hyperlactatemia. Transrectal and transabdominal ultrasound revealed echogenic fluid (pus) within the uterus. Purulent uterine fluid culture yield Escherichia coli. A diagnosis of pyometra was made. After medical treatment without clinical improvement, an exploratory laparotomy was performed, and a 360‐degree uterine left horn torsion was identified with the pyometra and multiple corpora lutea on both ovaries. Ovariohysterectomy was performed and the ewe recovered uneventfully.  相似文献   
12.
[目的]研究日粮中添加薰衣草精油替代饲用抗生素对肉仔鸡生产性能及胴体品质的影响.[方法]将300只1日龄AA肉仔鸡随机分成4个处理组(每组设3个重复,每个重复25只),对照组饲喂基础日粮加抗生素,试验Ⅰ组、Ⅱ组、Ⅲ组日粮为基础日粮,分别添加薰衣草精油0.4、0.8、1.2(0~2周)和0.2、0.4和0.6 mL/kg(3 ~6周).[结果]日粮中添加薰衣草精油与添加抗生素比较,对肉仔鸡的平均日增重、料重比、死淘率和胴体品质等生产性能指标的影响不显著(P>0.05);除了试验组Ⅲ的腿肌率与抗生素组相比有显著降低外(P<0.05),其它胴体品质指标与抗生素组相比无显著性差异(P>0.05).试验组的平均死淘率(0.86;)低于抗生素组的死淘率(3.1;);试验组Ⅰ比抗生素组日增重提高了1.87; (P >0.05),料重比降低了0.53; (P >0.05).[结论]从肉仔鸡41 d末重、料重比、死淘率等指标综合评定来看,用薰衣草精油替代肉仔鸡饲用抗生素是可行的,0~2周和3~6周日粮中分别添加薰衣草精油0.4和0.2 mL/kg的效果较好.  相似文献   
13.
为了筛选出适合我国种植的澳洲坚果品种,对我国澳洲坚果主产区9个主要品种的产量和品质进行分析。结合澳洲坚果产业的健康发展,建议我国目前的澳洲坚果主要推广品种使用桂热5号(Own choice)和桂热6号(900#),在广西、广东和攀枝花等地的辅助品种可使用桂热7号(695#)和桂热8号(788#)等,在云南辅助品种可使用桂热7号(695#)、桂热8号(788#)、344#、660#和741#等。  相似文献   
14.
1999年至2000年,山西省太岳山林局应用人工合成的华北落叶松鞘蛾性信息素对华北落叶松鞘蛾进行了监测,并开展了大量诱杀试验。结果表明,该引诱剂对华北落叶松鞘蛾雄蛾有较强的引诱作用,60个诱捕器在成虫扬飞期共诱到鞘蛾成虫51万头,应用诱捕器后,林地内华北落叶松鞘蛾被害率下降50.1%,虫口密度下降81.2%。可用于对华北落叶松鞘蛾的监测和防治。  相似文献   
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16.
The objective of this study was to investigate the common forms of reproductive disorders and trends of fertility in cattle and buffaloes in Middle Egypt, and investigate nutritional deficiencies or imbalances as a cause of infertility. During the period from 2003 to 2006 a total of 4276 animals (2755 cattle and 1521 buffaloes) were examined, during winter and summer at three districts of Middle Egypt. Based on the owner complains, animals were categorized as anestrum, repeat breeder and those for pregnancy diagnosis. Feedstuffs of these districts were assessed for nutrient and mineral contents. Animals were examined by rectal palpation and by transrectal ultrasonography. The results showed that, ovarian inactivity was the most common cause of anestrum, whereas endometritis was the main frequent finding of repeat breeding. District, season and year affected the incidences of infertility. The pregnancy rate remained constant (cattle) or increased (buffaloes) from 2003 to 2006. The incidence of ovarian inactivity in both species decreased over the same period. In winter, the commonly used feedstuffs would be adequate to supply the animals with needs, but in summer, rations seem to be deficient in many essential nutrients. In conclusion, ovarian inactivity is the main cause of infertility in cattle and buffaloes in Middle Egypt. There is a link between poor nutrition in summer and the high incidence of ovarian inactivity. Fertility trends during the past few years are encouraging.  相似文献   
17.
The current study investigated the possibility of using the AMH concentration as a predictor of the ability of Korean Hanwoo cows to produce cumulus‐oocyte complexes, embryos that survive after transfer as well as the pregnancy outcome of surrogates. Eight sessions of ovum pick‐up (OPU) were performed with 19 donor cows at an interval of 3–4 days. Antral follicle count (AFC), oocyte quality and in vitro embryo development were recorded for each cow. Embryos produced from cows with different AMH profiles were transferred into recipients (n = 96). Cows in the high (≥0.25 ng/ml) and intermediate (0.1≥ to <0.25 ng/ml) AMH groups had a significantly higher AFC per OPU session (20.40 ± 1.36 and 16.91 ± 1.52, respectively; mean ± standard deviation) than cows in the low AMH group (<0.1 ng/ml; 12.19 ± 2.14). In addition, more cumulus‐oocyte complexes per donor were recovered in the high (11.46 ± 1.22) and intermediate (7.38 ± 0.83) AMH groups than in the low AMH group (4.77 ± 0.44). The percentage of oocytes reached blastocyst stage was significantly higher in the intermediate (47.0%) and high (38.5%) AMH groups than in the low AMH group (32.3%). The number of embryos produced per cow was higher in the high (3.9 ± 0.2) and intermediate (6.9 ± 0.6) AMH groups than in the low AMH group (2.2 ± 0.3). The percentage of embryos that gave birth to viable calves when transferred into recipients was higher for those derived from cows in the intermediate AMH group (50.7%) than for those derived from cows in the low (35.7%) and high (36.4%) AMH groups. In conclusion, a single measurement of AMH concentration predicted the in vitro embryo production potential of donor Korean native cows before OPU and is linked with embryo viability after transfer into recipients.  相似文献   
18.
全面推行学分制是高校教学改革的深化, 是教育和教学改革的一个发展阶段。但由于学分制所带来的思想教育、学生党建等新情况、新问题, 应值得所有教育者认真思考和研究的。本文围绕学分制实行后给学生党建工作带来的“四难”以及如何应对提出了一些理论和实践的思考。  相似文献   
19.
Lipids are an important nutritional component of the avian egg. A review of the literature was completed to determine the fatty acid compositions in egg yolk from some avian species. Additionally, the nutritional influence of lipid and lipoprotein content on the plasma of male participants during 30‐day feeding was discussed. The ostrich eggs had the highest unsaturated fatty acid and the lowest cholesterol content in relation to other avian species. Ostrich had a higher proportion of 18:3n‐3 (p < 0.01) compared with other species. Chicken yolk numerically contained much higher levels of 22:6n‐3 than those found in turkeys, quails and geese, but the amount of 22:6n‐3 in ostrich egg was lower by comparison with other species (p < 0.01). After the storage of eggs at the room temperature, there was a notable loss of vitamin E (vitE) in the yolks of all species and this decrease was marginal (p < 0.01) in ostrich compared with other species. There were significant (p < 0.05) increases in plasma low‐density lipoprotein (LDL) level in all male subjects. Plasma high‐density lipoprotein (HDL) level decreased (p < 0.05) only in men who were fed chicken or ostrich eggs daily. Consumption of different species’ eggs had no influence on the total male plasma cholesterol and triglyceride levels. LDL‐C:HDL‐C ratio increased (p < 0.05) after goose and turkey egg consumption. Consumption of one egg/month by healthy human subjects had no effect on serum total cholesterol and triglyceride. The LDL‐C:HDL‐C ratio (which is a strong predictor of coronary heart disease risk) increased, although non‐significantly, by consuming chicken, quail and ostrich eggs.  相似文献   
20.
Understanding how multiple disturbances affect species population structure is crucial for designing a better conservation strategy of threatened species. In this paper, we assessed the disturbance patterns and evaluated their effects on the population structure of Afzelia africana, in two different bioclimatic zones of the Republic of Benin. The main disturbances in the studied area included branch pruning and debarking. Individuals of medium size (20–40 cm) were mostly pruned and debarked. The percentages of pruning and debarking were similar at population level across the two studied bioclimatic zones (t = ?0.04, p = 0.96; t = 0.73, p = 0.48). Examining this at individual level, pruning was similar but debarking was higher in the Sudanian zone (12.14 ± 0.93%) than in the Sudano-Guinean zone (7.44 ± 0.88) (W = 40859, p < 0.001). Population structure was bell-shaped in the Sudanian zone regardless of the disturbance level. In contrast, in the Sudano-Guinean zone, mildly disturbed populations showed an inverse J-shaped structure, whereas those highly disturbed were bell-shaped. This underlined the climatic (dryness) and disturbance effects on the establishment and recruitment of small trees into the next life stage in tropical savanna ecosystems. Good regeneration pattern and the largest individuals were found within the protected areas, demonstrating the prominent role of protected areas for the species conservation. Therefore, we suggested that conservation efforts should be extended to populations outside the protected areas. Forestry department should establish firebreaks networks to protect small individuals and facilitate their recruitment, as well as the regulation and enforcement should be improved on the sustainable use of the species.  相似文献   
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