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61.
S. Marcus M. Bernstein G. Ziv A. Glickman M. Gipps 《Veterinary research communications》1994,18(5):331-336
Consecutively collected semen samples from a breeding bull were found to be contaminated withPseudomonas aeruginosa. Palpation through the bull's scrotum revealed inflammatory changes suggestive of chronic orchiepididymitis in one testicle. For 10 months, all the bull's 13 ejaculates were discarded because the post-thaw viability was <20%. Norfloxacin nicotinate was injected intramuscularly into the bull at 5 mg/kg daily for 7 days. Serum and semen samples were collected at 24-h intervals during the course of treatment and afterwards and were assayed for NFN concentrations. Drug concentrations in the semen, by microbiological assay, during treatment and up to 120 h after the last treatment ranged from 2.6 to 5.1 µg/ml, 14.2 to 43.2 times the corresponding serum drug levels.P. aeruginosa was not isolated from the semen 4 or 15 days after the last injection but was re-isolated after 32 and 64 days. A second similar course of NFN was administered andP. aeruginosa was not isolated from semen samples collected on four occasions, 6, 22, 44 and 94 days after the last treatment.Abbreviations HPLC
high-pressure liquid chromatography
- IM
intramuscular
- MIC
minimal inhibitory concentration
- NFN
norfloxacin nicotinate 相似文献
62.
The effect of acrosomal aberrations of the spermatozoa of Finnish Ayrshire bulls on the corrected non-return rate within 60 days of the first 500 inseminations was studied. The material consisted of sperm samples examined by the artificial insemination societies. All samples had been accepted for use in artificial insemination. One Giemsa-stained slide was studied for each of the 95 bulls concerned. Samples showing distinct acrosomal defects were studied by electron microscopy. Three different types of acrosomal aberration were found. One was obviously associated with subfertility in all 6 bulls in which it was detected. 相似文献
63.
64.
采用复方依葡柠解冻液 (EDTA 葡萄糖 柠檬酸钠 ,试验组 )与常用的单方柠檬酸钠解冻液 (2 .9%柠檬酸钠 ,对照组 )对肉用种公牛颗粒冻精进行解冻对照试验。结果显示 ,解冻后精子的复苏率 ,试验组与对照组相差不大 (P >0 .0 5 ) ;常温 (18~ 2 0℃ )和低温 (5~ 7℃ )下再贮存 ,精子的存活时间和生存指数 ,试验组高于对照组 ,且差异显著 (P<0 .0 5 ) ;解冻后在 (38± 2 )℃水浴中孵育 3h检查精子的完整顶体率 ,试验组极显著高于对照组 (P<0 .0 1)。适用于水牛的良好解冻液依葡柠 ,用做牛 (肉用牛 )的冻精解冻得到了理想效果 相似文献
65.
RE Hickson WJ Anderson PR Kenyon N Lopez-Villalobos ST Morris 《New Zealand veterinary journal》2013,61(4):176-183
AIM: To obtain an estimate of the incidence of assistance at calving in primiparous (first-calving) beef heifers and the prevalence of breeding heifers at 15 months of age in New Zealand in 2006,and to identify factors contributing to farmers' decisions regarding breeding strategies for heifers, using a survey of beef cattle farmers. METHODS: A questionnaire was sent to farmers listed in a Massey University database and to members of selected breed societies, as well as published in an industry newspaper; 331 valid responses were received. Information was gathered on the age and number of primiparous heifers, number of heifers assisted, and the importance of various reasons for and against breeding heifers at 15 months of age. Respondents were also required to outline the criteria used for selecting bulls to join with heifers, and the strategies used to manage dystocia in primiparous heifers. RESULTS: Sixty-five (95% CI=58–71)% of respondents had only 2-year-old primiparous heifers in 2006, whilst a further 11 (95% CI=8–16)% had both 2- and 3-year-old primiparous heifers. The mean reported incidence of assisted calving was 7.0 (95% CI=6.4–7.5)% for 2-year-old primiparous heifers and 1.7 (95% CI=1.2–2.2)% for 3-year-old primiparous heifers. The reported incidence of assistance at calving within individual herdsranged from 0 to 100% for 2-year-old heifers. Respondents with bull-breeding herds most commonly observed their primiparous 2-year-old heifers twice daily, whilst respondents with commercial herds most commonly observed them once daily during calving. The most important reason for breeding heifers at 15 months of age was “increased profit”, whereas the most important reason for not breeding them at that age was “concern about rebreeding performance of 2-year-old heifers”. Estimated breeding value (EBV) for birth weight was the factor considered most frequently when selecting bulls to join with maiden heifers; age of bull and body shape of bull were the next most frequently considered factors. Selection of an appropriate bull was the most common strategy used to manage dystocia in 2-year-old beef heifers. CONCLUSIONS: The majority of respondents calved their heifers at 2 years of age, and “increased profit” was the primary motivator. Concern about the rebreeding performance of 2-year-old heifers was the most important reason among the remainder of respondents for not breeding heifers at 15 months of age. Dystocia in 2-year-old heifers was “not a problem” or “a minorproblem” in most herds, but there was much variation amongst herds. 相似文献
66.
Summary Twenty‐seven calves of the Dutch Friesian breed were housed after their first grazing season and divided into 3 groups, each of 9 animals. Two of the groups were treated with oxfendazole 9.06 per cent suspension administered either orally or intraruminally, whilst the third group was retained as an untreated control. No differences in efficacy were observed between the two treated groups and oxfendazole administered by either route was 100 per cent effective in removing adult populations of the major strongylids and trichostrongylids present. 相似文献
67.
选取发育正常、健康无病、经标准化育肥、年龄为24月龄的秦川肉牛新品系公牛5头进行屠宰及胴体分割,测定屠宰率、净肉率、胴体产肉率、肉骨比等产肉性能指标,并对里脊、西冷、眼肉、上脑、臀肉、胸肉、黄瓜条、牛腩、肋条肉、牛前10个部位取样进行水分、粗灰分、粗蛋白、粗脂肪、剪切力、失水率、系水力和熟肉率8项指标的测定。结果表明,秦川肉牛新品系公牛日增重、屠宰率、产肉率、胴体产肉率、肉骨比等生产性能较传统秦川牛均有较大幅度提高,经过标准化育肥,24月龄时已具备良好的肉用生产性能,达到国际优质肉牛品种标准;秦川肉牛新品系公牛胴体不同部位间肉品质差别较大,通过对其10个部位牛肉品质评定,西冷、上脑、里脊、眼肉为高档肉,肋条肉、臀肉、黄瓜条为中档肉,牛腩、胸肉、牛前为低档肉。 相似文献
68.
69.
Fresh semen and blood samples from 20 Karan Fries bulls (4–6 years of age), maintained at the Artificial Breeding Complex of the National Dairy Research Institute, Karnal, were collected for one year. All the bulls had 60 chromosomes, comprising 58 acrocentric autosomes and 2 sex chromosomes, with X as the larger and Y as the smaller submetacentric. The mean lengths of Yp and Yq; the total length of the Y chromosome and the length ratio were 1.10±0.01 m, 1.83±0.02 m, 2.92±0.02 m and 62.46%±0.18%, respectively. Analysis of the length measurements of the the Y chromosomes in Karan Fries bulls showed that all the measurements, viz., the short arm of the Y chromosome, the long arm of the Y chromosome, the total length of the Y chromosome and the variation in length of Y chromosome, varied significantly among bulls. All the seminal parameters, the volume of semen, mass activity, initial motility, concentration, live sperm count and the total abnormal sperm count, were significantly affected by bulls, whereas season had a significant effect on all the seminal parameters except the total abnormal sperm count. No significant relationship between the ratio of the long arm to the total length of the Y chromosome and seminal attributes was observed. 相似文献
70.
收集了武汉市牛奶公司八一奶牛场和武昌奶牛场的1995-1999年原产奶量数据,在进行305d产奶量校正后,采用动物模型BLUP原理和相应的计算机软件(PEST)对数据进行了统计分析,在模型中考虑的效应包括牛场、年度、季节、胎次、个体的育种值等,其中每年的季节是根据武汉市的特点,划分为3个阶段,计算得出了武汉市近年所用的荷斯坦种公牛的育种值,并据此对公牛进行了排序。 相似文献