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121.
邓培华  王娟  洼桑措  付建 《中国饲料》2021,1(6):107-110
本研究旨在探讨马铃薯藤饲喂水平对山羊生长性能、养分消化率和胴体特征的影响。试验将平均初始体重为(14.42±0.24)kg的40头山羊随机分为4组,每组5个重复,每个重复2头。T1组仅饲喂干草,T2组饲喂干草+100%马铃薯藤,T3组饲喂干草+50%马铃薯藤+50%浓缩料,T4组饲喂100%浓缩料。在为期10周的饲养试验后屠宰,分析胴体特征。结果:T2~T4组山羊的末重、增重、日增重和饲料效率显著高于T1组(P<0.05),其中T1组山羊的日增重和增重均表现出负增长。T2~T4组山羊的干物质、有机物、粗蛋白质和代谢能摄入量均显著高于T1组(P<0.05),但T2和T3组山羊中性洗涤纤维摄入量显著高于T1和T4组(P<0.05)。T2、T3和T4组山羊干物质和有机物表观消化率显著高于T1组(P<0.05),T4组山羊粗蛋白表观消化率显著高于T1和T2组(P<0.05)。T2、T3和T4组山羊屠体重、热胴体重、眼肌面积、可食用内脏和不可食用内脏重量均显著高于T1组(P<0.05)。T3组山羊的屠宰率显著高于其他组(P<0.05)。结论:在干草为基础的日粮中添加马铃薯藤可以提高山羊采食量、饲料转换率、养分消化率、屠宰率和胴体特征。 [关键词]马铃薯藤|山羊|生长性能|消化率|胴体特征  相似文献   
122.

Background

Vomiting is a common complication associated with the use of hydromorphine for pre‐emptive analgesia in dogs. The ideal anti‐emetic protocol for prevention of this complication has not been established.

Hypothesis

Maropitant administered concurrently or before hydromorphone would reduce the incidence of vomiting, signs of nausea, ptyalism, and increased panting compared to administration of acepromazine or a 0.9% saline control.

Animals

Sixty mixed‐breed female dogs scheduled for ovariohysterectomy.

Methods

Randomized, blinded, placebo‐controlled experimental study. Dogs were assigned to 4 experimental groups with 15 dogs per group. All groups received 0.2 mg/kg of hydromorphone IM. Group “Control” received 0.1 mL/kg saline SC 30–45 minutes before hydromorphone, group “Marop1” received 1 mg/kg maropitant SC 30–45 minutes before hydromorphone, group “Ace” received 0.02 mg/kg IM acepromazine 30–45 minutes before hydromorphone, and group “Marop2” received 1 mg/kg SC maropitant concurrently with hydromorphone. A trained and blinded observer documented adverse events from the time hydromorphone was administered until the time dogs were induced for surgery.

Results

Marop1 had significantly less vomiting (0%) compared to Control (87%; P < .01) and Ace (53%; P < .01). Marop2 had significantly less vomiting (27%) compared to Control (P < .01). Marop1 had significantly greater incidence of ptyalism (73%) compared to Ace (P < .01; 20%). Ace showed significantly less panting (33%) compared to Marop2 (93%; P < .01).

Conclusions and Clinical Importance

In healthy dogs, maropitant citrate administered before hydromorphone significantly decreases the incidence of vomiting in dogs but does not improve signs of nausea, ptyalism, or increased panting.  相似文献   
123.
With the advancement of assisted reproductive biotechnologies, preselecting the sex of offspring has become an important goal for cattle and other livestock breeding as well as for research. The aim of this study was to investigate the feasibility of producing enriched pools of X‐ or Y‐chromosome‐bearing sperm by vertical swim‐up through a long, narrow column. Sperm recovered from the top portion of the column was predominantly Y‐bearing (60%, p < 0.05), which were capable of fertilizing matured oocytes and produce significantly more male embryos compared with standard swim‐up protocol.  相似文献   
124.
抗逆高羊茅新品种黔草1号的特征特性   总被引:1,自引:2,他引:1  
介绍了抗逆高羊茅新品种黔草1号(Festuca arundinacea Schreb.cv.Qiancao No.1)的育种过程及其优良特性。在贵州省及四川、广西、新疆等地种植的种子平均产量比对照品种凌志和原始群体高出20%以上。返青期比引进品种凌志提前7天,枯黄期晚3天;是目前我国育成的自主知识产权优良抗逆草坪型新品种,是运动场草坪、环境绿化、生态治理和改良天然草场的理想草种之一。适宜我国长江中下游低山、丘陵等地区种植。  相似文献   
125.
The synchronization of follicular waves with medroxyprogesterone acetate (MAP) and oestradiol‐17β (E2‐17β) prior to ovarian superstimilation in anoestrous ewes reduces the variability in superovulatory responses by an unknown mechanism. Follicle stimulating hormone (FSH) is a primary promoter of antral follicular development, but the relevance of circulating FSH concentrations to the superovulation performance in ewes has not been examined. Eighteen anoestrous Rideau Arcott ewes (May–June) were superovulated with Folltropin®‐V (porcine FSH), with (n = 8; treated ewes) or without (n = 10; control ewes) a single i.m. dose of 350 μg of E2‐17β, given on the sixth day of a 14‐day treatment with MAP‐releasing intravaginal sponges (60 mg). The superovulatory treatment, begun 6 days after E2‐17β injection, consisted of six i.m. applications of Folltropin®‐V given twice daily (at 08:00 and 16:00 h), followed by an i.m. injection of GnRH (50 μg). Blood samples collected every 8 h throughout the 3‐day treatment, were analysed by radioimmunoassays for concentrations of ovine and porcine FSH, using species‐specific standards and primary antibodies. Serum concentrations of oFSH were greater (p < 0.05) in the controls compared to treated ewes at 40, 64 and 72 h and the variability in mean oFSH concentrations was greater (p < 0.05) in control ewes at 40, 48, 64 and 72 h after the 1st Folltropin®‐V injection. There were no differences (p > 0.05) between the two groups in serum concentrations of pFSH. Significant correlations were recorded between the number of corpora lutea (CL) and oFSH concentrations at 8 h (r = 0.72, p < 0.05), 16 h (r=0.63, p < 0.05) and 64 h (r = 0.84, p < 0.01) after the 1st Folltropin®‐V injection. The total number of recovered embryos was positively correlated to oFSH concentrations at 56 h (r = 0.69, p < 0.05). We concluded that changes in endogenous FSH concentrations during ovarian superstimulation with pFSH might contribute to the variability in superovulatory responses in ewes.  相似文献   
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