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131.
Bilateral third degree burns were created on the flanks of eight miniature swine. Each animal had one side treated daily with low intensity direct (LIDC) of 400 microamperes (muA) by contact electrode for 2 hours morning and afternoon until healing occurred. The polarity of the electrode was negative in 4 pigs and positive in 4 pigs. One group of 4 pigs had the eschar surgically removed 24 hours post burn. Weekly biopsies and cultures were taken of treated and control wounds. Results indicated: local treatment of 400 muA LIDC did not hasten or delay healing of thermal third degree burns; escharectomy hastened wound healing by 10 days, and superficial proteus infection occurred in 80% of all wounds.  相似文献   
132.
Chicks and chickens maintained under commercial conditions were vaccinated against Newcastle Disease via drinking water. Prior and after different times of vaccination blood samples were drawn from different numbers of birds and checked for HI antibodies. The modes of distribution of the antibody titers within the random sample were assayed. The following results were obtained:
1. 1. On the basis of the distribution of the serum titers can be concluded whether the antibody level within a flock is increasing or decreasing.
◦ —A right steep asymmetry can be observed up to 20 days post vaccination.
◦ —In the phase of maximal antibody levels an almost symmetric distribution of the titers is present.
◦ —In later times (more than three weeks p. vacc.) the distribution shows a left steep asymmetry (Poisson distribution).
2. 2. A poisson distribution is also observable during the elimination of maternal antibodies of chicks until complete elimination.
3. 3. The mode of distribution of the HI titers in sera of day-old chicks correlates with the mode of distribution of the dams. Therefore, conclusions are possible from the status of the chicks to the dams and reverse.
4. 4. Factors which interfere with the mode of distribution are:
◦ —Two or more peaks after vaccination of chickens. This indicates an uneven immune response within the flock.
◦ —Distributions with several peaks may also occur if flocks are composed of day-old chicks from parent flocks with different levels of antibody titers.

Résumé

Des poulets et des poussins maintenus dans un élevage conventionnel furent vaccinés contre la maladie de Newcastle par un vaccin administré dans l'eau de boisson. Avant et à différents temps après vaccination, des échantillons de sang furent prélevés sur un certain nombre de poussins et les anticorps inhibants de l'hémagglutination furent recherchés. Les modes de la distribution des titres en anticorps pour les échantillons pris au hasard furent recherchés. Les résultats suivants furent obtenus:
1. 1. Sur la base de la distribution des titres sériques, on peut conclure si le taux en anticorps à l'intérieur d'une population a augmenté ou diminué.
◦ —Une courbe asymétrique avec un pic déplacé vers la droite peut être observée 20 jours après la vaccination.
◦ —La phase correspondant au taux maximal en anticorps présente une distribution presque normale.
◦ —Plus tard, (au-delà de 3 semaines après la vaccination), la distribution apparaît asymétrique avec un déplacement vers la gauche (distribution de Poisson).
2. 2. Une distribution de Poisson peut aussi être observée au moment de l'élimination des anticorps d'origine maternelle chez des poussins jusqu'à complète élimination.
3. 3. Le mode de distribution des titres en anticorps inhibant l'hémagglutination dans des sérums de poussins d'un jour correspond au mode de distribution observé chez les mères. Des conclusions peuvent donc être faites à partir de l'état immunologique des poussins vis-à-vis des mères et viceversa.
4. 4. Les facteurs qui peuvent intervenir dans le mode de distribution sont:
◦ —Deux pics ou plus après la vaccination des poussins. Ceci indique qu'il existe une réponse immunitaire inégale dans la population.
◦ —Des distributions avec plusieurs pics peuvent être également observées si les populations sont composées de poussins de un jour provenant de populations parentales ayant des taux différents de titres en anticorps.
Keywords: Newcastle disease; vaccination NDVMots-clé: Maladie de Newcastle; vaccination Newcastle  相似文献   
133.
134.
The causative agent of stomatitis pneumoenteritis complex was isolated in domesticated goats and Vero cell culture. It was identified immunologically and morphologically as identical with the "Peste des Petits Ruminants" virus. There were cross reactions between stomatitis pneumoenteritis complex virus isolate and rinderpest virus by immunodiffusion and complement fixation tests but no cross neutralization. Goats recovered from stomatitis pneumoenteritis complex were protected against a challenge with rinderpest virus that was lethal to control goats. Ultrastructural morphology revealed intracytoplasmic and intranuclear inclusions made up of random arrays of fibrillar strands. Pleomorphic particles budded from the plasma membrane of infected cells and enveloped virions were seen extracellularly. Specific ferritin tagging was demonstrated in the stomatitis pneumoenteritis complex virus infected cells treated with homologous and peste des petits ruminants viral antibody systems but little, if any, tagging in the heterologous rinderpest system.  相似文献   
135.
Male experimental rats (100 gm liveweight) were distributed into 10 groups of 8 animals each and received balanced diets, with the exception of lysine which was added to the diets in graded amounts in such a way that the lysine content of the diets ranged from 2.44 to 5.92 gm/16 gm N. After a feeding period of 7 days the animals received 3H- and 14C lysine injected intraperitoneally, 4 animals of each group were investigated for the total CO2 excretion and 14CO2 excretion during the first 2 hrs after the injection and for the urinary excretion of radioactivity (48 hours). The remaining animals in each group were used for determining the plasma amino acids and for establishing the specific radioactivity of free lysine in the liver and muscles after an 1-hour incorporation period. Total CO2 excretion was not found to be influenced by the lysine contents while the level of excretion of 14C activity through CO2 and that of specific 14C activity of CO2 increased with increasing lysine concentrations. This produced a broken curve pattern, showing an increased release of 14CO2 (under maintenance conditions) if the diet contained 4 gm lysine/16 gm N and more. Investigations for the specific 14C activity of free lysine in the liver, the main site of lysine oxidation, showed that the increase in 14CO2 release was due to an enhanced rate of lysine catabolism and was not brought about by changes in the pool volume or in specific radioactivity. The levels of urinary 14C excretion were not found to be related to the lysine content of the diets, whereas the curve pattern of 3H excretion observed 5 to 8 hrs after injection was similar to that of 14CO2 excretion. The lysine content of blood plasma and the content of free lysine in the liver increased continuously with increasing levels of dietary lysine. The methodological studies made in the present paper showed that in scientific research a determination of amino acid requirements on the basis of CO2 oxidation data may be a very exact and sensitive method. It will also yield values for maintenance requirements.  相似文献   
136.
Of 62 strains of Staphylococcus aureus, isolated from milk samples of dairy-cows with staphylococcic mastitis from five agricultural enterprises, 68 p. c. could be typified as bacteriophages. In 42 typified strains, altogether 17 different phage pictures were found, in which case, in the different agricultural enterprises, the number of phage picture fluctuated between 1 and 8. Phage picture 42 D was found and dominated in all the agricultural enterprises. Of the typified strains, 76% could be ranked only into one phage group and 24% in the "M" group (= miscellaneous). Of 32 typified strains, 56.3% belonged to phage group IV, 25% to group III, 12.5% to group I, and 6.2% to group II.  相似文献   
137.
During recent years it has been evident that a number of gastrointestinal hormones are potent calcitonin secretagogues, and it has been suggested that a gastrointestinal-thyroid C cell system exists as a part of post prandial calcium homeostasis. In the present study the hypocalcaemic effect of pentagastrin, a synthetic peptide with gastrin effects, was studied in lactating cows. Intravenous infusion of pentagastrin caused marked hypocalcaemia and hypophosphataemia in the cows. Thyroidectomy completely abolished the hypocalcaemic and hypophosphataemic effects of the peptide. The results thus suggested that the effects of the peptide were due to release of endogenous calcitonin.  相似文献   
138.
139.
An eruptive condition seen on certain mucous membranes of dogs occurs frequently but often asymptomatically. Lesions have been found to be present in over 60 percent of male dogs. The infection is probably due to a canine herpes virus and has been termed conveniently but inaccurately "dog pox". In many cases lesions are present without observable clinical signs but severe irritation, especially related to lesions in the lower bowel, can give rise to marked symptoms which may be confused with abnormality of the para-anal sacs, or to chronic diarrhoea of a type suggestive of colitis. The incidence, sites of infection and possible syndromes which may be ascribed to the condition are briefly discussed on a clinical basis only.  相似文献   
140.
1. The effect of heat treatment and enzyme supplementation on the nutritive value of barley was studied.

2. In only one experiment was weight gain significantly improved when the barley was heated.

3. Autoclaving barley at 120 °C for 30 min reduced dietary dry matter digestibility and treating the barley with dilute acid before heating had no effect on its nutritive value.

4. Supplementing diets containing commercial barley with a‐amylase produced slightly conflicting results in that there was an improved weight gain, food conversion efficiency and digestibility value in two of three experiments.

5. The digestibility and metabolisable energy values of a North American six‐row spring barley (Glacier) were significantly improved by enzyme supplementation.

6. The effect of the enzyme on diets containing a high amylose barley (Glacier Pentlandfield) was positive but not significant.  相似文献   

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