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1.
低死亡率和较高的饲料利用率 ,看来是鸡抗氧化状态得到改善的结果。增高日粮维生素E的含量并应用有机硒可减少肺高压 (腹水症 )引起的死亡。  相似文献   
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Luteolytic doses of the Tham salt of PGF2 or one of its synthetic analogues cause premature regression of, the corpus luteum between the 5th and the 16th day of the oestrous cycle, inducing, 2 to 4 days after the injection, endcrine changes similar to a normal lultolysis and oestrus. After insemination at the time of this oestrus or at predefined times 72 to 96 hours after the injection, fertility is similar to that in controls. The paractical use of prostaglandins for the synchronization of oestrus in a herd of randomly cyclic animals takes account of the fact that only animals between the 5th and the 16th day respond to an injection. Various techniques are proposed, notably a double injection with an interval of 10–12 days.
Kurzfassung Luteolytische Dosen eines Tham'schen Salzes von PGF2, oder einer dessen synthetischen Analogen bringen vorzeitige Regressionen des corporis lutei zwischen dem 5ten und dem 16ten Tage hervor. Als Folge dieser Regressionen entwickeln sich innerhalb 2 bis 4 Tage nach der Einspritzung endokrine Veränderungen, die der normalen Luteolyse und Brunst ähnlich sind. Nach einer Besamung zur Zeit dieser Brunst oder zu vorherbestimmten Zeiten und zwar 72 und 92 Stunden nach der Einspritzung wird die gleiche Frunchtbarkeit wie in unbehandelten Kontrollen beobachtet. Nur ein Teil einer zyklischen Herde reagiert auf Prostaglandin, und es werden daher verschiedene Methoden der Viehwirtschaftsführung zur Überwindung dieses Problems erörtert, wie auch den Gebrauch einer Doppeleinspritzung von Prostaglandin mit einem 10 bis 12 tägigen Abstand zwischen den Behandlungen.

Resume Les doses lutéolytiques de sel Tham de PGF2 ou d'un de ses analogues synthetiques causent une reégression prématurée du corps jaunne entre le 5ème et le 16ème jour du cycle provoquant, 2 à 4 jours après l'injections, des changements endocriniens semblales à une lutéolyse normale et à un oestrus. Après l'insémination au moment de cet oestrus ou à des temps prédéfinis de 72 à 96 heures après l'injection, la fertilité est semblable à celle des animaux témoins non traités. L'utilisation pratique des prostaß-landinesd pour la synchronisation des chaleurs dans un troupoeau de femelles cyclées tient compte du fait que seules les femelles entre le 5ème et 16ème jour du cycle répondent à une injection. Différentes techniques sont proposées, notamment la double injection à 10–12 jours d'intervalle.

Riassunto Le dosi luteolitiche del sale Them PGF2 o di uno dei suoi analoghi sintetioi causano una regressione prematura del corpo giallo tra il 5o ed il 16o giorno del ciclo provooando, dopo un periodo che va dai 2 ai 4 giorni dall'iniezione, dei cambiamenti endocrini simili ad una luteolisi normale o ad un estro. Dopo l'inseminazine, nel momento di questo estro oppure in tempi predeterminati, in un periodo compreso tra 72 e 96 ore dopo l'iniezione, la fertilità è simile a quella jdegli animali di controllo non trattati. L'utilizzazione poratioa della prostaglandine per la sincronizzazione dei oalori in una mandria di femmine cicliche dimostra che le femmine rispondono all'iniezione soltanto tra il 5o ed 16o giorno del ciclo. Si propongono diverse techniche, in poarticolasre la doppia iniezione ad un intervallo di 10–12 giorni.
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Plasma concentrations of PAG‐1 are used for pregnancy diagnosis and as a marker of placental/foetal well‐being, while those of PAG‐2 may be an indicator of abortion risk in Neospora caninum‐infected cows. Studies have shown that N. caninum infection modifies PAG‐1 and PAG‐2 patterns in maternal blood plasma. However, no prior work has examined the effects of N. caninum infection on concentrations of PAGs in foetal fluids. In this study, PAG‐1, PAG‐2 and pH levels were determined in the amniotic and allantoic fluids of foetuses collected at 152 days of gestation from control uninfected dams and from dams experimentally infected with N. caninum on Day 110 of gestation. Foetal fluids from infected foetuses had significantly higher PAG‐2 concentrations (p = 0.026) and pH values (p = 0.02) than fluids from non‐infected foetuses. In infected foetuses, significantly higher concentrations of PAG‐1 (p < 0.001) and PAG‐2 (p < 0.001) were detected in fluid samples showing antibodies against N. caninum than those without antibodies. Moreover, pH values were significantly higher (p = 0.011) in foetal fluid samples with antibodies than in samples from non‐infected foetuses. In conclusion, this is the first report on the effect of N. caninum infection on PAG levels in foetal fluids. Our results indicate that following the experimental infection of dams with N. caninum on Day 110 of gestation, foetal fluids collected from the infected foetuses of these dams featured higher PAG‐1 and PAG‐2 levels and pH values than fluids from non‐infected controls, provided that the samples tested showed the presence of antibodies. The clinical implications of these findings are that following infection with N. caninum, most cows will experience some level of placental damage and that this injury correlates with foetal fluid PAG levels and pH.  相似文献   
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The reproductive performance of female Nile tilapia, Oreochromis niloticus L., reared in ponds under tropical conditions was studied. The experiments used stock matured to the age of 2–4 months and a size of 30–50 g. Oocyte development proved a better indicator for the determination of the size at first maturation than the development of the gonado-somatic index. The Nile tilapia became ‘stunted' in the sense that early breeding took place, but the somatic growth of the stock still continued. This result indicates that the earlier breeding of Nile tilapia is not a real bottleneck for the expansion of this production sector. No relationship was found between the condition factor and the size at first maturation or the relative fecundity. This led to the conclusion that aggravation of the living conditions is not a major cause of earlier breeding of pond-reared O. niloticus.  相似文献   
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In many African countries, the Bayoud is a common disease spread involving the fungus Fusarium oxusporum f. sp. albedinis (Foa). The induction of plant natural defenses through the use of seaweed polysaccharides to help plants against pathogens is currently a biological and ecological approach that is gaining more and more importance. In the present study, we used alginate, a natural polysaccharide extracted from a brown algae Bifurcaria bifurcata, to activate date palm defenses, which involve phenylalanine ammonia-lyase (PAL), a key enzyme of phenylpropanoid metabolism. The results obtained showed that at low concentration (1 g·L−1), alginate stimulated PAL activity in date palm roots 5 times more compared to the negative control (water-treated) after 24 h following treatment and 2.5 times more compared to the laminarin used as a positive stimulator of plant natural defenses (positive control of induction). Using qRT-PCR, the expression of a selection of genes involved in three different levels of defense mechanisms known to be involved in response to biotic stresses were investigated. The results showed that, generally, the PAL gene tested and the genes encoding enzymes involved in early oxidative events (SOD and LOX) were overexpressed in the alginate-treated plants compared to their levels in the positive and negative controls. POD and PR protein genes selected encoding β-(1,3)-glucanases and chitinases in this study did not show any significant difference between treatments; suggesting that other genes encoding POD and PR proteins that were not selected may be involved. After 17 weeks following the inoculation of the plants with the pathogen Foa, treatment with alginate reduced the mortality rate by up to 80% compared to the rate in control plants (non-elicited) and plants pretreated with laminarin, which agrees with the induction of defense gene expression and the stimulation of natural defenses in date palm with alginate after 24 h. These results open promising prospects for the use of alginate in agriculture as an inducer that triggers immunity of plants against telluric pathogens in general and of date palm against Fusarium oxysporum f. sp. albedinis in particular.  相似文献   
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Lactating dairy cows (n = 72) with a mature corpus luteum (CL) (diameter of > or = 17 mm) determined by ultrasonography and having a follicle with a diameter of > or = 10 mm were randomly assigned to four groups. Cows were treated with cloprostenol i.m. once or twice, or with dinoprost i.m. once or twice with an 8-h interval. The ovaries of each cow were scanned daily by transrectal ultrasonography to measure the changes in the areas of CL and the largest follicle and to determine the occurrence of ovulation. Oestrus was verified twice daily. In addition, blood sample was withdrawn from each cow daily for measuring progesterone (P4) concentrations. Significant decreases in the percentage changes relative to areas of CL and P4 concentrations or increases in the percentage changes in the area of the largest follicle on day 0 were detected in each group during the experiment. However, the type of the drug and the number of the treatments had no significant effect on those parameters. Cows ovulated with or without showing oestrus (group A) and cows exhibiting no oestrus and ovulation (group B) were also evaluated. In contrast to the mean area of the CL and the mean concentration of P4 on day 0, the mean area of the largest follicles between the two groups on day 0 differed significantly. Significant decreases in the percentage changes relative to the area of the CL and P4 concentration or increases in the percentage changes relative to the area of the largest follicle during the experiment were detected in both groups; however, there were no group differences. Treatment of dairy cows with two injections of prostaglandins (cloprostenol or dinoprost) at an 8-h interval resulted in more cows being observed in oestrus within 5 days after treatment and having significantly higher pregnancy rate than those treated with a single prostaglandin injection.  相似文献   
10.
Tissue samples were collected postmortem from 126 sheep at five lymphoreticular sites by different techniques. The three most successful combinations of sites and techniques were: the third eyelids, using a forceps and scissors, which provided a mean (se) of 5.32 (0.70) lymphoid follicles per 5 microm tissue section, a mandibular lymph node, using a Biopty gun, which gave 1.19 (0.26) lymphoid follicles per 5 microm tissue section, and tonsil, using a biopsy forceps, which gave 1.14 (0.27) lymphoid follicles per 5 microm tissue section. These three techniques were repeated once a month for five months on five sheep under general anaesthesia, and their clinical effects were compared with five control sheep which were restrained and anaesthetised in the same way but from which no biopsies were taken. Most lymphoid follicles (3.47 [0.58] per 5 pm tissue section) were obtained by using the third eyelid biopsy technique. There were no clinical side effects associated with the biopsy procedure. There were increases in the plasma concentration of cortisol in all the animals, suggesting that the restraint and anaesthesia were more stressful than the biopsy procedure.  相似文献   
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