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1.
R. T. Pepper 《The Journal of small animal practice》1964,5(2):179-181
Abstract— A case of nephrolithiasis in a young boxer bitch is described and the surgical approach outlined.
Résumé— L'auteur décrit un cas de lithiase rénale chez une jeune chienne de race boxer et présente les grandes lignes de la thérapeutique chirurgicale.
Zusammenfassung— Es wird der Fall eines Nierensteinleidens bei einer jungen Boxerhündin beschrieben und ein Abriss des chirurgischen Eingriffs gegeben. 相似文献
Résumé— L'auteur décrit un cas de lithiase rénale chez une jeune chienne de race boxer et présente les grandes lignes de la thérapeutique chirurgicale.
Zusammenfassung— Es wird der Fall eines Nierensteinleidens bei einer jungen Boxerhündin beschrieben und ein Abriss des chirurgischen Eingriffs gegeben. 相似文献
2.
从健康的化香(Platycarya strobilacea Sieb. et Zucc.)根际土壤中分离获得生防菌HK18-8,为探究其对辣椒炭疽病的生防潜力,通过对峙培养和孢子萌发试验发现,HK18-8显著抑制短尖刺盘孢(Collectotrichum acutatum)的菌丝生长和分生孢子萌发,其抑菌带达到10mm,孢子萌发抑制率为70.15%;进行离体辣椒果实接种试验表明,HK18-8菌悬液对辣椒炭疽病的防治效果达到88.58%,其预防效果高于治疗效果,HK18-8的发酵液和菌悬液的防病效果显著;采用平板稀释法测定其在辣椒果实的定殖能力,处理9 d时仍能保持10~6 cfu·g~(-1)以上;根据形态特征、生理生化特性及16S rRNA序列同源性,HK18-8菌株鉴定为多粘类芽孢杆菌(Paenibacillus polymyxa)。 相似文献
3.
The effects of pyrethroids were studied upon isolated segmental nerves and neuromuscular junctions in both susceptible (Cooper) and knockdown-resistant (kdr; super-kdr) strains of housefly larvae (Musca domestica L.). Isolated segmental nerves contained neither cell bodies nor synaptic contacts; thus, any effects of pyrethroids were attributed solely to their actions upon voltage-dependent Na+ channels. Threshold concentrations of the type II pyrethroid, deltamethrin, required to elevate the spontaneous firing rate of these nerves were determined. Both resistant strains were about ten times less sensitive to deltamethrin than the susceptible strain, but insensitivity of super-kdr nerves was no greater than in the less resistant kdr strain. At neuromuscular junctions, the minimum concentrations of pyrethroids needed to trigger massive increases in the frequency of miniature excitatory postsynaptic potentials (mEPSPs) were determined for deltamethrin and the type I pyrethroid, fenfluthrin. With fenfluthrin there was no detectable difference between the junctions of kdr and super-kdr strains, which were both about ten-fold less sensitive than Cooper junctions. With deltamethrin, kdr junctions were about 30 times less sensitive than those of Cooper; super-kdr junctions were dramatically insensitive to deltamethrin, being some 10000- and 300-fold less sensitive than those of Cooper and kdr respectively. Thus, in the synaptic assay, super-kdr conferred an extension in resistance over kdr only against the type II pyrethroid, it being ineffective against fenfluthrin. We suggest that kdr resistance comprises at least two site-insensitive areas within the nervous system. One involves insensitivity of the Na+ channel and has similar efficacy in both kdr and super-kdr strains against type I and II pyrethroids; the other is associated with the presynaptic terminal and is particularly effective in super-kdr resistance against type II pyrethroids. The latter could be associated with Ca2+-activated phosphorylation of proteins involved with neurotransmitter release. Such phosphorylation reactions are known to be perturbed by pyrethroids, especially by type II compounds. 相似文献
4.
Jonsson NN Matschoss AL Pepper P Green PE Albrecht MS Hungerford J Ansell J 《Veterinary parasitology》2000,88(3-4):275-285
The effects of vaccination with the Bm 86 vaccine TickGARD(PLUS) against infestation with cattle tick (Boophilus microplus) and of holding cattle on a feedpad until 09:00 hours after the morning milking was tested on 40 mid lactation Holstein cattle using a factorial design. Vaccination resulted in a 56% reduction in tick numbers in the field over one generation, and a 72% reduction in laboratory measures of the reproductive efficiency of ticks. The liveweight gain of vaccinated cattle over 27 weeks was 18.6 kg higher than that of controls, and vaccinated cattle tended to have lower somatic cell count in milk (SCC). There were no other significant differences in measures of production. Cattle kept on the feedpad after the morning milking carried 26% more ticks than those returned immediately to their paddocks. 相似文献
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6.
The in vivo faecal egg count reduction test (FECRT) is the most commonly used test to detect anthelmintic resistance (AR) in gastrointestinal nematodes (GIN) of ruminants in pasture based systems. However, there are several variations on the method, some more appropriate than others in specific circumstances. While in some cases labour and time can be saved by just collecting post-drench faecal worm egg counts (FEC) of treatment groups with controls, or pre- and post-drench FEC of a treatment group with no controls, there are circumstances when pre- and post-drench FEC of an untreated control group as well as from the treatment groups are necessary. Computer simulation techniques were used to determine the most appropriate of several methods for calculating AR when there is continuing larval development during the testing period, as often occurs when anthelmintic treatments against genera of GIN with high biotic potential or high re-infection rates, such as Haemonchus contortus of sheep and Cooperia punctata of cattle, are less than 100% efficacious. Three field FECRT experimental designs were investigated: (I) post-drench FEC of treatment and controls groups, (II) pre- and post-drench FEC of a treatment group only and (III) pre- and post-drench FEC of treatment and control groups.To investigate the performance of methods of indicating AR for each of these designs, simulated animal FEC were generated from negative binominal distributions with subsequent sampling from the binomial distributions to account for drench effect, with varying parameters for worm burden, larval development and drench resistance. Calculations of percent reductions and confidence limits were based on those of the Standing Committee for Agriculture (SCA) guidelines. For the two field methods with pre-drench FEC, confidence limits were also determined from cumulative inverse Beta distributions of FEC, for eggs per gram (epg) and the number of eggs counted at detection levels of 50 and 25. Two rules for determining AR: (1) %reduction (%R) < 95% and lower confidence limit <90%; and (2) upper confidence limit <95%, were also assessed. For each combination of worm burden, larval development and drench resistance parameters, 1000 simulations were run to determine the number of times the theoretical percent reduction fell within the estimated confidence limits and the number of times resistance would have been declared.When continuing larval development occurs during the testing period of the FECRT, the simulations showed AR should be calculated from pre- and post-drench worm egg counts of an untreated control group as well as from the treatment group. If the widely used resistance rule 1 is used to assess resistance, rule 2 should also be applied, especially when %R is in the range 90 to 95% and resistance is suspected. 相似文献
7.
Summary In this study we evaluated the impact of five annual liquid sewage-sludge applications on the organic C and N content of a furrow-irrigated desert soil. Mineralization rates showed that sludge organic matter is mineralized rapidly (65% per year). Resistant residual sludge organic matter accumulation resulted in a theoretical increase in total soil organic C of 0.013% for the single sludge rate or 0.038% for three annual applications. These small additions were not detected in sludged soils at any depth to 270 cm. Similarly, increases in total soil N were not detected at any depth. However, soluble forms of organic C and N did increase in sludged soils relative to the non-sludged soils. In addition, soluble C:N ratios decreased significantly in the sludged soils. Soluble C and N also increased with depth due to leaching. This study therefore shows that applications of liquid sludge onto desert soils could affect the status of underground aquifers with respect to nitrate pollution. 相似文献
8.
Cows with chronic endometritis were treated by using uterine irrigation, prostaglandin or oestradiol benzoate. An attempt was made to relate the success of treatment to the nature of the discharge. No statistically significant differences were demonstrated between the different treatments, nor did the severity of the disease as judged by the amount of pus in the discharge affect the success of treatment. Progesterone and in some cases a metabolite of prostaglandin were measured in a milk sample taken at the time of treatment. Increased prostaglandin concentrations were found in 69 of 71 samples examined but they were not correlated with the progesterone concentrations. These measurements from cases of endometritis were higher than those from normal cows in the immediate post partum period and during established oestrous cycles. Treatment with prostaglandin when the concentration of progesterone was high was not more effective than when progesterone concentrations were low. Treatment had less influence on the subsequent fertility of the cow than other factors investigated; in particular, the sooner after calving the cow was treated the greater was the chance of success. This was thought to be due, at least in part, to the high rate of spontaneous recovery. Before treatment can be evaluated effectively a method must be found to identify persistent cases. 相似文献
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10.
A computer program was used to analyse data from a large commercial pig unit over two years to assess reproductive efficiency and the efficiency of weaner production. Monthly inspections of the farm and quarterly post mortem examinations of all dead pigs provided further information. The effects of controlled changes in management on production were assessed. Overall the number of piglets reared per sow per year was increased from 15-1 to 17-2 and the eight-week weights improved from a mean of 10-3 kg to 15-0 kg during the two year-study period. 相似文献