氢氧化钠对线叶嵩草种子萌发的影响

线叶嵩草种子采集后在冰箱中保存半年发芽率仅3.3％,保存1年半后只有13.0％。用浓度为0.005—0.05g/ml的氢氧化钠处理3 h后,采集保存半年和1年半的种子发芽率分别可达36％和72％。NaOH对线叶嵩草种子萌发有增效和负效两方面,最佳处理浓度为0.03g/ml。     

影响紫花苜蓿花药培养因素的探讨与分析

从外植体的选取时期及处理、培养基及激素组合、培养条件等多方面分析,影响紫花苜蓿花药培养的因素,并对花粉植株倍性鉴定、驯化移栽和花粉植株的遗传稳定性进行了初步探讨。     

肉牛母牛生产瘫痪的防治

[目的]为了掌握张掖肉牛母牛生产瘫痪的发生与治疗方法。[方法]对一例产前瘫痪母牛和一例产后瘫痪母牛进行药物治疗。[结果]两例生产瘫痪母牛经过准确诊断和及时合理治疗得到康复。[结论]生产瘫痪是发生于高产奶牛的代谢性疾病,但近年来张掖肉牛母牛偶有发生,对张掖肉牛母牛生产瘫痪的治疗,只要诊断正确,治疗及时,合理用药,定能取得满意的治疗效果。     

Endodontic treatment of a mandibular premolar abscess in a horse: A case study

A pulpar abscess of cheek tooth 307 (according to the Triadan numerical system) was diagnosed in a 7‐year‐old female Quarter Horse. History included a painful response to palpation in the mandibular region for approximately 4 weeks. Symptoms included swelling of the mandibular bone with subsequent fistulisation. A complete intraoral examination was performed and no lesions or abnormalities were found. Digital radiographs of the mandibular arcade demonstrated a periapical lesion of cheek tooth 307. Various therapeutic options were considered, including standing oral extraction, retrograde repulsion and endodontic therapy. Together with the client, a decision was made to perform endodontic therapy, with the double aim of preserving the tooth and maintaining normal molar occlusion. This was done under general anaesthesia without apicectomy, and using materials commonly used in the field of human endodontics. Following surgery, radiographs were taken and confirmed the complete sealing of the pulp canals. Recovery was uneventful and no post operative complications were observed. A complete intraoral follow‐up examination was performed one year after surgery, and revealed normal eruption and occlusion of the tooth involved. Radiographic examination confirmed the correct position and integrity of the sealant material, as well as normal perialveolar bone structure. This case report indicates that endodontic therapy, following the above protocol, involving pulpectomy and sealing of the pulp cavity, represents a valid alternative to the more commonly used technique of tooth extraction.     

生物法处理养殖污水中氨氮的研究进展

综述近几年生物方法处理养殖污水中氨氮的研究进展及实际应用,并对大规模处理养殖污水方面提出了一些思考和展望,期望在今后的研究工作中能够探索出高效率、低成本、无二次污染的生物方法处理养殖污水中的氨氮.     

Effectiveness of strategic anthelmintic treatments in the control of gastrointestinal nematodes and <Emphasis Type="Italic">Fasciola gigantica</Emphasis> in cattle in Iringa region,Tanzania

A longitudinal field trial was conducted to determine the effectiveness of strategic anthelmintic treatments in the control of gastrointestinal (GI) nematodes and Fasciola gigantica in cattle. A total of 167 cattle (6–18 months) from three large-scale dairy farms, four traditional farms and nine small-scale dairy farms were randomly selected. The selected animals on each farm were ear tagged and allocated into three groups based on live weight and treated as follows: Group T4 was treated with albendazole 10% drench at 10 mg/kg four times a year (mid rainy, end of the rain, mid dry and late dry/early rainy season). Group T2 was treated with albendazole 10% drench at 10 mg/kg two times a year (mid rainy and late dry/early rainy season). Group UT remained as untreated control. Faecal, blood and pasture samples were taken every month for 13 months. In addition, individual body weight (BWT) was measured on every sampling date. Results showed that two and four strategic treatments significantly reduced faecal egg counts (FEC) by 49.5% and 62.3% respectively compared to untreated control animals (P < 0.001). Two and four strategic treatments per year significantly reduced the proportion of animals passing Fasciola eggs in faeces by 30.6% and 51.7% (P < 0.001), respectively. Animals treated two and four times a year significantly outgained untreated animals by 14.8 kg and 17.7 kg respectively at the end of the trial (P < 0.05). The management system had a significant effect on packed cell volume and the proportion of animals passing Fasciola eggs in faeces (P < 0.05). The programme of two strategic treatments per year was only effective in controlling GI nematodes. It is concluded that a programme of four strategic treatments per year was effective in controlling GI nematodes and F. gigantica and improved weight gain.     

兔球虫病药物防治研究进展

兔球虫病是严重危害养兔业发展的寄生虫病之一。长期以来,兔球虫病主要依靠化学药物和中草药等进行防治,由于球虫极易产生耐药性,给药物防治带来了困难。论文从兔球虫生物学特性、防治兔球虫病的药物等方面做一综述。     

Effects of treating rice straw with urea or urea and calcium hydroxide upon intake, digestibility, rumen fermentation and milk yield of dairy cows

Three, multiparous Holstein crossbred dairy cows with initial body weight of 385 ± 19 kg were randomly allocated to 3 treatments of rice straw (T1 = untreated rice straw; T2 = 5.5% urea-treated rice straw (5 g urea in 100 ml water to 100 g air-dry (91% DM) straw); T3 = 2.2% urea + 2.2% calcium hydroxide treated rice straw (2.0 g urea and 2.0 g Ca(OH)₂ in 100 ml to 100 g air-dry (91% DM) straw) according to a 3 × 3 Latin square design. Each period lasted for 21 days in which feed, feces and rumen fluid were collected during the last 7 days for chemical analyses. The findings revealed significant improvements in dry matter intake and digestibility by using 5.5% urea-treated rice straw and 2.2% urea + 2.2% calcium hydroxide treated rice straw. Ruminal pH and NH₃-N were found higher (P < 0.05) as compared with urea-treated rice straw fed group, while blood urea nitrogen and milk urea nitrogen were in normal ranges. Volatile fatty acid concentrations especially those of acetic acid were decreased (P < 0.05) and those of propionic acid were increased (P < 0.05), thus acetic acid:propionic acid was subsequently lowered (P < 0.05) in cows fed with 5.5% urea-treated rice straw and 2.2% urea + 2.2% calcium hydroxide treated rice straw, respectively. Moreover, ruminal viable and cellulolytic bacterial counts were enhanced by urea and calcium hydroxide treatments. Milk protein and fat concentrations were additionally increased by respective treatments while 3.5% fat-corrected milk was highest; ranking from 2.2% urea + 2.2% calcium hydroxide treated rice straw, 5.5% urea-treated rice straw and urea-treated rice straw fed groups. Based on this study, implications could be made that using 2.2% urea + 2.2% calcium hydroxide treated rice straw for straw treatment could be an alternative treatment to 5.5% urea treatment with regards to its effectiveness and treatment cost for lactating dairy cows.     

南方早熟砂梨缺镁黄叶症诊断与矫治

通过对福建省德化县早熟砂梨“黄叶病株”及“正常植株”叶片及土壤的营养诊断分析：黄叶病株叶片平均含镁量0.131%,极显著低于正常植株0.328%;黄叶症较重的果园土壤交换态镁含量低12.6～24.5㎎/㎏及土壤酸性强pH3.6～4.5,诊断结论砂梨叶片黄化现象为镁素缺乏所致。矫治试验效果,叶面喷施1%硝酸镁3次,可以叶色转绿;12月份土壤基施钙镁磷肥株1.3 kg,翌年5月份后有明显矫治效果。     

牛GV期卵母细胞冷冻保存后发育潜力的研究

二甲基亚砜(DMSO)、丙二醇(PROH)、乙二醇(EG)和甘油(GL)4种冷冻保护剂程序化冷冻牛GV期卵母细胞的结果表明,EG和PROH的保护效果比GL和DMSO好。4种不同冷冻方法冷冻保存牛GV期卵母细胞,比较解冻后卵母细胞的体外成熟率、受精后卵裂率。结果表明,在程序化冷冻法与细管玻璃化法(Straw)之间的差异不显著(P>0.05),在开放式拉管法(OPS)与毛细玻管法(GMP)之间的差异不显著(P>0.05);但OPS和GMP与程序化冷冻法和Straw之间的差异极显著(P<0.01)。玻璃化冷冻效果优于程序化冷冻。说明GMP和OPS玻璃化冷冻优于Straw玻璃化冷冻。说明可以采用GMP方法冷冻保存牛GV期卵母细胞。