Utilisation de souches non pathogènes de Fusarium pour lutter contre les fusarioses: situation actuelle dans la pratique1

Des travaux antérieurs ayant permis de démontrer que des souches non pathogènes de Fusarium sont impliquèes dans les mécanismes de résistance des sols aux fusarioses, nous avons tenté d'utiliser des souches de Fusarium sélectionnées pour lutter contre ces maladies. Les bons résultats obtenus en conditions expérimentales nous ont conduits à mettre en place un réseau d'expérimentation en conditions normales de culture dans des serres de production de tomates et de melons. Le premier problème à résoudre est celui de la production massive d'inoculum, de sa conservation et de son introduction dans les sols et substrats de cultures. La production de l'inoculum est réalisée en fermenteur, les propagules produites soni récupérées par filtration et mélangées avec du talc, support inerte qui après avoir été séché assure la conservation et la distribution de cet inoculum dans des conditions satisfaisantes. Les quantités d'inoculum produites en 1985–86 ont permis de réaliser plusieurs essais de lutte dans des conditions normales de production. L'inoculum protecteur est apporté, soit dans les substrats de culture hors sol au moment de leur ensachage, soit dans les sols en place, immédiatement après leur désinfection au bromure de méthyle. L'installation de la souche protectrice est suivie régulièrement grace à des analyses microbiologiques et la gravité de la maladie est notée régulièrement en cours de culture. Les résultats enregistrés en 1986, variables d'une situation à l'autre, ne permettent pas de porter un jugement définif sur l'intéret de ce procédé de lutte. Ils sont cependant intéressants et permettent d'organiser sur des bases plus solides notre campagne d'expérimentation 1986–87.     

Frequency of a FAS ligand gene variant associated with inherited feline autoimmune lymphoproliferative syndrome in British shorthair cats in New Zealand

Abstract

AIMS

To determine the frequency of the FAS-ligand gene (FASLG) variant associated with feline autoimmune lymphoproliferative syndrome (FALPS) and the proportion of carriers of the variant in three British shorthair (BSH) breeding catteries in New Zealand.     

Anesthetic Potency of Desflurane in the Horse: Determination of the Minimum Alveolar Concentration

Objective — To determine the minimum alveolar concentration (MAC) of desflurane (DES) in the horse.
Study Design — Prospective study.
Animals — Six healthy adult horses (three males and three females) weighing 370 ±16 kg and aged 9 ±2 years old.
Methods — Anesthesia was induced with DES vaporized in oxygen via a face mask connected to a large-animal, semiclosed anesthetic circle system. The horses were endotracheally intubated and positioned in right lateral recumbency. Inspired and end-tidal DES were monitored using a calibrated Ohmeda RGM 5250 multigas analyzer (Ohmeda-BOC, Spain). The MAC of desflurane that prevented gross purposeful movement in response to 60 seconds of noxious electrical stimulation of oral mucous membranes was determined.
Results — The time from the start of DES administration to lateral recumbency was 6.1 ±0.9 min. The MAC of DES in these horses was 7.6 ±0.4%. Time required for the animal to regain sternal recumbency after 98 ±4 minutes of anesthesia was 6.6 ±0.5 minutes and the time to standing was 14.3 ±2.7 minutes.
Conclusions — The MAC of desflurane in these horses was 7.6 ±0.4%. DES provided a rapid induction to, and recovery from, anesthesia.
Clinical Relevance — Desflurane offers the potential for more precise control during anesthesia, and may allow a faster and uneventful recovery. It is important to know the MAC of an inhalant to use it clinically.     

Lactobacilli counts in crop,ileum and caecum of growing broiler chickens fed on practical diets containing whole or dehulled sweet lupin (Lupinus angustifolius) seed meal

1. Four experiments with growing broiler chickens were carried out to study the effects of the inclusion in their diets of lupin (Lupinus angustifolius ) seed meal on E. coli and lactobacilli counts in crop, ileum and caeca at 3 or 4 weeks of age. 2. Diets were formulated to contain the same amounts of metabolisable energy (12.55 MJ/kg) and protein (210 g/kg). Raw whole (heat-untreated) or dehulled sweet (low in alkaloids) lupin seed meal (400 and 320 g/kg respectively) were used to prepare the lupin-based diets, whose protein content was completed with either defatted soyabean meal or casein. 3. Final body weight and food intake of chickens fed on whole lupin seed meal diets were lower than controls, but gain: food ratios were not different. However, birds given the diet with dehulled lupin seed meal had similar body weight, food intake and gain: food values as those of controls. 4. While E. coli counts were not affected, lactobacilli numbers were consistently increased compared to controls in all intestinal sections of chickens fed on the whole or dehulled lupin-based diets, irrespective of the age of the birds or the presence of soyabean meal or casein in the diet. The lactobacilli species isolated were: Lactobacillus fermentum, L. acidophilus, L. salivarius and L. brevis 5. The results suggest that the use of whole or dehulled sweet lupin seed meal in diets for growing broilers might enhance the growth of lactic acid-fermenting bacteria in the gut.     

奶牛温氏支原体16SrRNA基因的PCR扩增、克隆及分析

目的对奶牛温氏支原体16SrRNA基因进行PCR扩增及克隆分析。方法从自然感染体的广西奶牛无菌采集血液,分离温氏支原体并提取病原基因组,用血营养菌的16SrRNA基因的通用引物进行PCR扩增,将扩增产物克隆到PGEM-Teasy载体后进行溺,I序和分析,并与Genebank上搜索的温氏支原体相应序列进行比较,建立系统发育树。结果PCR扩增得到长约1．5kb的扩增片段,测序结果显示该片段全长为1453bp,同源性分析表明该序列与Neimark公布的温氏支原体（前称温氏附红细胞体）（AF016546）的16SrRNA基因序列同源性达到97．4％,与系统发育进化树表明本株温氏支原体同本地株的关系较近,而与国外株的新缘关系较远。国内公布的广西株同源性为99．8％。结论结果表明证实该病原为温氏支原体,从分子生物学水平证实了温氏支原体在广西的存在。由于本试验分离得到的牛温氏支原体与国外发表的牛温氏支原体核苷酸序列相差2．6％,因此两者的基因型存在一定的差异,这对该病的分子流行病学分析具有一定的意义。     

Reproductive Performance of Rabbit Does Artificially Inseminated via Intravaginal Administration of [des-Gly 10, d-Ala6]-LHRH Ethylamide as Ovulation Inductor

This study was aimed to evaluate the reproductive performance of rabbit does artificially inseminated (AI) with a GnRH analogue [des‐Gly10, d ‐Ala6]‐LHRH. ethylamide to induce ovulation by intravaginal administration, delivered in the seminal dose. In a preliminary experiment, 39 does were divided into three groups (n = 13) that, at the time of AI, received the following ovulation induction treatments: (i) control group: 20 μg of gonadorelin administered intramuscularly; (ii) 25 μg of the GnRH analogue added to the seminal dose; (iii) 30 μg of the GnRH analogue added to the seminal dose. Fertility did not differ between the three groups (control: 80.6%, group 2: 82.8%, group 3: 73.3%). In a second experiment, a large‐scale field trial was conducted to test the use of 25 μg of the GnRH analogue [des‐Gly10, d ‐Ala6]‐LHRH ethylamide delivered in the seminal dose (n = 270) against 20 μg of gonadorelin administered intramuscularly. Fertility was higher (p < 0.05) when ovulation was induced by intravaginal administration of the GnRH agonist (91.1% vs 85.6%). Prolificacy or mortality at birth was never affected by the ovulation induction treatments. In a third experiment, two groups of does [control group (n = 39): ovulation was induced using 20 μg of gonadorelin administered intramuscularly; treatment group (n = 40): ovulation was induced using 25 μg of [(des‐Gly10, d ‐Ala6)‐LHRH ethylamide added to the seminal dose] were inseminated at 42‐day intervals for five successive AI cycles, to test the response to the GnRH agonist after repeated intravaginal administration to the same animals. Fertility and prolificacy were not influenced by the ovulation induction treatment neither there was an interaction between treatment and parity. The last experiment was aimed to determine whether it could be possible to add the GnRH agonist to the semen in the AI Center, just after semen collection and dilution, or it would have to be added in the farm, immediately before AI. Kindling rates did not significantly differ when ovulation was induced by intramuscular injection of gonadorelin (84.5%) or when the GnRH agonist was added to the seminal dose just at the moment (93.8 %) or 24 h before AI (90.4 %), but it was significantly lower when the hormone was added to the semen 32 h before AI (76.3 %). Prolificacy, however, was not influenced by the ovulation induction treatment.     

Field comparison of the interferon-gamma assay and the intradermal tuberculin test for the diagnosis of bovine tuberculosis

An extensive field comparison of the gamma interferon (IFN-gamma) assay and the single intradermal tuberculin test for the diagnosis of bovine tuberculosis was conducted in Australia. The specificity of the IFN-gamma assay was determined by testing more than 6000 cattle from tuberculosis-free herds and varied from 96.2% to 98.1%, depending on the cut-off point chosen to define a positive reactor. For the sensitivity trial, cattle from herds being de-populated because of bovine tuberculosis were examined with both assays. The sensitivity of the IFN-gamma assay was shown to be significantly higher than the single intradermal tuberculin test and varied from 76.8% to 93.6% depending on the method of interpretation. A maximum overall sensitivity of 95.2% was obtained by testing with the IFN-gamma and the tuberculin test in parallel. The superior sensitivity of the IFN-gamma assay and the ability to adjust the sensitivity of the system depending on the task involved, will provide the Australian Tuberculosis Eradication Campaign with a valuable additional test to enable it to accomplish its goals.     

肃南牦牛屠宰性能和肉品质研究

为研究肃南牦牛的屠宰性能及肉品质,揭示其遗传特性,选取12头(公母各半)4岁放牧肃南牦牛进行屠宰试验和肉品质分析,并与文献中已报道的甘南牦牛、天祝白牦牛、雪多牦牛、环湖牦牛等进行了对比分析.结果显示,肃南牦牛的活重和胴体重均高于环湖牦牛和天祝白牦牛,屠宰率高于查乌拉牦牛和环湖牦牛,净肉率高于甘南牦牛和环湖牦牛,熟肉率高...     

青海省海南州高寒草地荒漠化治理技术与对策

总结了海南州高寒干旱草地荒漠化特征和成因,分析出气候变化、毁草开荒、超载过牧、鼠类危害、利用不当、执法不严等是草地荒漠化的主要原因,通过对荒漠化草地实行人工补播优良牧草、灭除毒草、消灭鼠害、禁牧封育、暖棚养畜、营造饲料护牧林等措施,提出了防止草地荒漠化的对策及治理技术.