青海草地建设投资与草地产出灰色关联分析

用灰色关联分析方法，对青海省草地建设投资与草地产出作相关分析。结果表明：两者相关性较强，关联度系数γｙ０１８＝０．７１６８（畜牧业产值）和γｙ０２８＝０．７２４４（畜产品产量）；在草地建设分项投资中，与草地产出关联度最大的为灭鼠投资，分别为γｙ０１５＝０．９１６２（牧业产值）和γｙ０２５＝０．８８８５（畜产品产量），其次顺序为种草投资（γｙ０１２＝０．８２６６和γｙ０２２＝０．８１３１），草地围栏     

Effects of food withdrawal and transport on 5- to 10-day-old calves

The effects of food withdrawal for 30 hours and transport for up to 12 hours on 5- to 10-day-old calves were determined by monitoring plasma concentrations of glucose, beta-hydroxybutyrate, urea, lactate and creatine phosphokinase. In addition gamma-glutamyl transferase activity, packed cell volume, total plasma protein concentration, bodyweight and rectal temperature were recorded. Food withdrawal for 30 hours caused hypoglycemia but calves maintained normothermia and although their beta-hydroxybutyrate level increased indicating lipid mobilisation, the changes in blood urea level were minimal indicating low amino acid catabolism. When calves were transported for 12 hours in addition to having food withdrawn for 30 hours, they remained normoglycemic for six hours longer than non-transported calves, probably due to an effect of muscular activity during bracing against truck movements. Stocking calves at a lower density during transport apparently had a beneficial effect, as calves were able to lie down throughout the journey and therefore produced a similar metabolic profile to resting, non-transported animals. Transport and food withdrawal had no obvious effects on calf hydration. The results of this study suggest that food withdrawal for up to 30 hours and transport for up to 12 hours had no detrimental effects on the metabolism of healthy and clinically normal calves. With correct feeding regimes and transport protocols, welfare compromise in young, healthy calves being transported for up to 12 hours can be minimised when they are slaughtered within 30 hours of the start of transport.     

Subchondral cystic lesions of the proximal extremity of the tibia in horses: 12 cases (1983-2000)

OBJECTIVE: To determine clinical and radiographic features of subchondral cystic lesions (SCL) of the proximal extremity of the tibia in horses that could be used to classify these lesions as being related to osteochondrosis or osteoarthritis and to evaluate results of surgical debridement. DESIGN: Retrospective study. ANIMALS: 12 horses with 14 SCL. PROCEDURE: Medical records and radiographs obtained before and after treatment were reviewed. RESULTS: In 6 young horses (8 lesions), SCL were considered to be related to osteochondrosis; all involved the lateral tibial condyle. The remaining 6 horses were mature and had radiographic evidence of osteoarthritis in addition to SCL. Arthroscopic debridement was performed in 4 horses in which lesions were considered to be a result of osteochondrosis and in 3 horses with osteoarthritis. Three horses in which SCL were considered to be a result of osteochondrosis performed athletically after debridement. Two horses with moderate osteoarthritis returned to work after arthroscopic debridement but at a lower level of athletic performance. One horse with SCL related to osteochondrosis responded to medical treatment and went on to race. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that arthroscopic debridement of SCL is feasible in horses in which lesions involve the cranial portion of the lateral or medial tibial condyle, and that treated horses may be able to perform athletically.     

Evaluation of single-nucleotide polymorphisms in CAPN1 for association with meat tenderness in cattle

Micromolar calcium activated neutral protease (CAPN1) was evaluated as a candidate gene for a quantitative trait locus (QTL) on BTA29 affecting meat tenderness by characterization of nucleotide sequence variation in the gene. Single-nucleotide polymorphisms (SNP) were identified by sequencing all 22 exons and 19 of the 21 introns in two sires (Piedmontese x Angus located at the U.S. Meat Animal Research Center in Clay Center, NE; Jersey x Limousin located at AgResearch in New Zealand) of independent resource populations previously shown to be segregating meat tenderness QTL on BTA29. The majority of the 38 SNP were found in introns or were synonymous substitutions in the coding regions, with two exceptions. Exons 14 and 9 contained SNP that were predicted to alter the protein sequence by the substitution of isoleucine for valine in Domain III of the protein, and alanine for glycine in Domain II of the protein. The resource populations were genotyped for these two SNP in addition to six intronic polymorphisms and two silent substitutions. Analysis of genotypes and shear force values in both populations revealed a difference between paternal CAPN1 alleles in which the allele encoding isoleucine at position 530 and glycine at position 316 associated with decreased meat tenderness (increased shear force values) relative to the allele encoding valine at position 530 and alanine at position 316 (P < 0.05). The association of maternal alleles with meat tenderness phenotypes is consistent with the hypothesis of CAPN1 as the gene underlying the QTL effect in two independent resource populations and presents the possibility of using these markers for selective breeding to reduce the numbers of animals with unfavorable meat tenderness traits.     

不同包装和药剂处理对冬雪蜜桃贮藏性的影响

不同包装与药剂配合处理能较好地保持果实的硬度,贮藏１３周后各处理组合的果实硬度比对照果分别高２１．４％～５９．５％。药剂和包装处理对果实的可溶性固形物含量没有明显的影响。冬雪蜜桃果心褐变主要与果实的衰老有关,ＧＡ_３和钙处理明显地减少贮藏期间果心的褐变程度。     

Investigation of the presence of ESBL-producing Escherichia coli in the North Wales and West Midlands areas of the UK in 2007 to 2008 using scanning surveillance

Between November 5, 2007 and November 4, 2008, faecal samples from cattle and sheep submitted for diagnostic purposes to the Aberystwyth and Shrewsbury Veterinary Laboratories Agency (VLA) (now AHVLA) regional laboratories (covering North Wales and the West Midlands) were screened for the presence of Escherichia coli that produces CTX-M extended-spectrum β-lactamase (ESBL) using the selective medium CHROMagar CTX. Samples from 113 farms were tested and eight ESBL-positive farms identified. Of these, six farms were identified via submissions of cattle faeces and two from sheep. Gene sequencing revealed both group 1 and group 9 CTX-M enzymes corresponding to CTX-M-14, CTX-M-14B (group 9) and CTX-M-15/28 (group 1). Analysis of these isolates by nanoarray revealed that some were carrying a range of virulence genes including ireA, iroN and prfB, which have been associated with extraintestinal pathogenic E coli, and were multidrug resistant. Geographical analysis with choropleth maps suggested that these CTX-M genes are relatively widespread in the North Wales and West Midlands study area. This work was carried out concurrently with the running of a VLA ESBL surveillance system, which has subsequently identified many more CTX-M positive farms in the UK.     

渐开线齿轮重合度与双齿啮合刍议

重合度是衡量齿轮传动平稳性和承载能力的一个重要指标,可反映在啮合过程中双齿啮合的比例。本文对齿轮啮合过程进行解析,阐述齿轮的双齿啮合比概念,并解析了齿轮的双齿啮合比的计算式,介绍并纠正学生在理解双齿啮合过程时的一个误区。     

Prevalence and duration of insensibility following electrical stunning in calves

Sixty-one calves were electrically stunned with 100-250 V currents (103-1806 mA) and the prevalence and duration of insensibility was assessed from their physical behaviour, the presence of epileptiform activity in their electrocorticograms, and the absence of visual evoked responses in their electrocorticograms. A current applied at 100 V across the head for 3 s failed to induce insensibility in all cases. Currents at 150-250 V induced insensibility in all calves and the shortest duration of insensibility was 44 s. It is recommended that a 150-200 V current would be appropriate for commercial use.     

青海省木本饲用植物资源分布特点及作用

青海省木本饲用植物共有22科,50属,201种。其中饲用价值较高、数量较多、分布较广的有8科,20属,68种。木本饲用植物是草地资源的重要组成部分,在天然草地中发挥着独特的作用,为全省畜牧业生产提供了丰富的饲草资源,维护着草地的生态平衡。