Culling and wastage in dairy cows in East Anglia   总被引：3，自引：0，他引：3  

G B Young  G J Lee  D Waddington  D I Sales  J S Bradley  R L Spooner 《The Veterinary record》1983,113(5):107-111

A culling survey in 80 Friesian dairy herds in East Anglia over four years investigated the age at, and reasons for, disposal or death. Failure to conceive was the most important reason except in very old animals. Low production was the second most common reason, culling being particularly heavy in the first two lactations. Mastitis was the major disease influencing wastage and increased with age until the sixth lactation. The percentage of culls for multiple reasons increased with age. There was a high proportion of young animals in most herds and the median lactating life of cows was about three years, equivalent to three lactations. Considerable variation in herd life demonstrated that there was substantial scope for improving herd longevity. Long living herds culled fewer animals for breeding problems in the early lactations and for mastitis in the later ones, enabling more animals to be culled as surplus and for production factors.  相似文献   

Serological evidence of Neospora caninum in alpacas from eastern Australia          下载免费PDF全文

JS King  JL Vaughan  PA Windsor 《Australian veterinary journal》2015,93(7):259-261

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Findings from an ovine parasitological monitoring service provided by a rural veterinary practice in New South Wales,Australia          下载免费PDF全文

MK Kozaruk  R Churchill  PA Windsor 《Australian veterinary journal》2015,93(4):112-120

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Corrections     

David M. Spooner  John B. Bamberg 《American Journal of Potato Research》1994,71(6):394-394

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AGEING OF HYDROLYSED IRON (III) SOLUTIONS1     

PA HO HSU  STEPHEN E. RAGONE 《European Journal of Soil Science》1972,23(1):17-31

Three 0.01m Fe(ClO₄)₃ Solutions of R= 0, 1, and 2, respectively, were studied over a period of 8 months, where R is referred to the HCO₃^?/Fe³⁺ mole ratio in preparation. The R= 0 solution was initially light yellow and clear but rapidly changed to a dense cloudy Suspension after a 9-day induction period. Hydrolysed species rapidly grew from <10 nm to >650 nm. Particles of intermediate size were not observed during the entire period of study. Settleable FeOOH precipi-tate was first observed in 5 weeks with 23 per cent of its iron noted as precipitate at the end of 5 months. The R= 1 and R= 2 Solutions were reddish-brown of low turbidity. Rapid hydrolysis and polymerization were observed immediately after preparation. The hydrolysed species gradually grew in size during ageing and no settleable FeOOH precipitate was observed for at least two years. A hypo-thesis based on Lamb and Jacques's model of Fe³⁺ hydrolysis is proposed to interpret the reactions taking place in these three Solutions. In the R= 0 solution, the initial number of nuclei for condensation is low, whereas the poten-tial supply of Fe(OH)₃ is abundant. In the R= 1 and R= 2 Solutions the number of nuclei initially formed is high, whereas a limited amount of mono-meric Fe(OH)₃ is available for condensation. The initial number of nuclei relative to the concentration of monomeric species is the key factor that governs the appearance and properties of these Solutions.  相似文献   

Wild potato (Solanum sect.Petota) germplasm collecting expedition to Mexico in 1993, with special reference toSolanum bulbocastanum Dunal andS. cardiophyllum Lindley     

Aaron Rodriguez  Ofelia Vargas  Eduardo Villegas  David M. Spooner 《Potato Research》1995,38(1):47-52

Summary A joint Mexico/United States expedition collected wild potato (Solanum sect.Petota) germplasm in Mexico between August 1–31, 1993. The purpose of the expedition was to expand germplasm and herbarium collections ofS. bulbocastanum andS. cardiophyllum. Collections were made from west-central to southern Mexico, and comprised 19 true seed and 37 tuber collections (45 collections in total) of 9 species and two putative natural hybrids.  相似文献   

Genetic diversity and origin of cultivated potatoes based on plastid microsatellite polymorphism     

Tatjana Gavrilenko  Olga Antonova  Anna Shuvalova  Ekaterina Krylova  Natalia Alpatyeva  David M. Spooner  Lubov Novikova 《Genetic Resources and Crop Evolution》2013,60(7):1997-2015

The origin of cultivated potatoes has remaining questions. In this study, 237 accessions of all cultivated species and 155 accessions of wild species closely related to cultivated potatoes, including their putative ancestors, were analyzed using 15 plastid microsatellites (SSRs) to investigate genetic diversity and their relationships with the wild species. We here used polymorphic plastid SSRs we developed from potato plastid genome sequences as well as already known plastid SSR markers. All 15 loci were polymorphic and identified a total of 127 haplotypes. Dramatic decreases in levels of genetic diversity were revealed in landraces in comparison with wild ancestor species. The plastid SSR results showed a decrease in haplotype number and diversity from Peru to both north and south. Phylogenetic analysis revealed two distinct groups. One of them, group A, contained the majority of accessions of cultivated species of the Solanum tuberosum Andigenum group including all accessions of cultivated diploid and triploid cytotypes of this group (S. chaucha, S. phureja, and S. stenotomum by a former taxonomic system) and most of tetraploid accessions of the S. tuberosum Andigenum group (S. tuberosum subsp. andigenum), and the majority of accessions of wild ancestors from the northern members of the S. brevicaule complex. Another group B comprised most of the wild species accessions and almost exclusively hybrid cultivated species which have introgressed plastid genomes from the other wild gene pools. Lack of clustering of traditional cultivated species (as used above) support a revised group classification of S. tuberosum.  相似文献   

Triangulation of methods using insect cell lines to investigate insecticidal mode‐of‐action     

Michelle Mak  Karren D Beattie  Albert Basta  David Randall  Zhong‐Hua Chen  Robert Spooner‐Hart 《Pest management science》2021,77(1):492-501

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Anaesthesia with ketamine/medetomidine in the rabbit: influence of route of administration and the effect of combination with butorphanol     

P Hedenqvist DVM    HE Orr† BVMS  Cert LAS    JV Roughan† BSc  PhD    LM Antunes† MSc DVM  & PA Flecknell† M.A Vet MB  PhD  DLAS  Dip ECVA  MRCVS 《Veterinary anaesthesia and analgesia》2002,29(1):14-19

Objective To compare the characteristics of anaesthesia induced with ketamine/medetomidine administered by the subcutaneous and intramuscular routes and to assess the effects of the addition of butorphanol to this combination. Study design Prospective randomised study. Animals Six female New Zealand White rabbits. Methods Rabbits were given one of four combinations of ketamine and medetomidine (K/M) either subcutaneously (SC) or intramuscularly (IM) on four successive occasions with a 7‐day interval between treatments. The dose combinations were; 15/0.25 mg kg^?1 SC; 15/0.25 mg kg^?1 IM; 15/0.5 mg kg^?1 SC, and 15/0.25 mg kg^?1 together with 0.4 mg kg^?1 butorphanol (K/M/B) SC. The effects of anaesthesia on arterial blood gas values and cardiovascular variables were recorded at predetermined time points. Toe and ear pinch reflexes were judged to determine the duration of surgical anaesthesia. Loss of the righting reflex was used to measure the duration of sleep time. Analyses used repeated measures analysis of variance. Results All groups lost the righting reflex and ear pinch response. Three animals in the groups that received K/M alone lost their toe pinch reflex, whereas four lost this reflex when given K/M/B. Time of onset of loss of the righting, toe and ear pinch reflexes did not differ significantly among the groups. The higher dose combination of medetomidine with ketamine and the combination of K/M/B produced a greater duration of loss of the ear pinch response than the lower dose of K/M administered by either route. No significant differences were found among the groups in the duration of loss of the toe pinch reflex. All animals developed a moderate bradycardia (mean heart rate <166 beats minute^?1) and moderate hypoxaemia (mean P_aO₂ < 6.0 kPa). Animals given butorphanol showed the greatest reduction in respiratory rate (31 ± 13 breaths minute^?1, p < 0.05) but this was not reflected in any significant differences in arterial PCO₂, PO₂ or pH among the groups. Conclusions Administration of K/M by the SC route produced equivalent effects in comparison to intramuscular administration. The addition of butorphanol increased the duration of anaesthesia, but produced a slight increase in the degree of respiratory depression. All dose rates resulted in hypoxaemia so oxygen should be administered when these combinations are used in rabbits. Clinical relevance Subcutaneous administration is both technically simpler and may cause less discomfort to the animal than IM injection, and so is preferred. The combination of K/M with butorphanol has relatively minor effects on the depth and duration of anaesthesia, so offers little advantage to the use of K/M alone.  相似文献   

论高校图书馆流通服务中的＂关键时刻＂管理     

帕提曼 《农业图书情报学刊》2013,(11):172-175

分析了高校图书馆流通服务和赢利性企业的共性,论述了高校图书馆流通服务管理应用“关键时刻”管理理论的可行性和必要性。提出了通过对高校图书馆流通服务中的一系列“关键时刻”的强化管理．提高流通服务质量,最大限度地满足读者需求的策略。  相似文献