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51.
Conflicting findings exist among studies on the effect of pneumonia on growth in pigs. We determined the extent of pneumonia in market-weight pigs by use of an objective, volumetric method and linear regression analyses of mean daily gain and days-to-slaughter weight on the percentage of pneumonic lung. In a range of extent of pneumonia between 1.33 and 70.44%, a 10% increase in the volume of pneumonic lung was associated with a decrease in mean daily gain by 41.1 g and a 16.7-day increase in number of days to a slaughter weight of 104.5 kg.  相似文献   
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Summary The results of three experiments aimed at controlling sarcoptic mange in goats in Indonesia are reported. In Experiment 1 treatment with ivermectin (0·2 mg/kg body weight) or coumaphos (0·05% dip solution) resulted in a significant reduction in mite numbers and an increase in body weight while in the untreated controls all animals had to be withdrawn from the experiment due to severity of infection. In Experiment 2 three treatment levels of ivermectin were shown to be equally effective in reducing mite numbers, while again all untreated control animals were withdrawn. The third experiment demonstrated a significantly greater reduction in mite numbers following two doses of ivermectin at a seven day interval when compared to a single dose. Again the majority of untreated control animals were withdrawn. Future control strategies and reasons for failure to eliminate the presence of mites are discussed.
Uso De La Ivermectina Para El Control De La Sarna Sarcoptica En Cabras En Indonesia
Resumen Se describen los resultados de tres experimentos a controlar sarna sarcóptica en cabras en Indonesia. En el experimento I, el tratamiento con ivermectina (200 µg/kg de peso corporal) o con cumafos (0.05 % de una solución para baño de inmersión) dió como resultado una reducción significativa en el número de parásitos y en el incremento de peso, mientras que en el grupo de controles no tratados, todos los animales tuvieron que ser retirados del experimento debido a la severidad de la infección. En el experimento 2 tres niveles de tratamiento con ivermectina, fueron igualmente efectivos en reducir el número de ácaros; mientras que los animales no tratados tuvieron también que ser retirados. El tercer experimento dió como resultado una reducción significativa en el número de ácaros después de dos dosis de ivermectina con un intervalo de siete días, comparada con una dosis sencilla. Otra vez, la mayoría de controles no tratados tuvieron que ser retirados. Se discute en este trabajo las estrategias futuras de control y las razones de las fallas para eliminar la presencia de ácaros.

Emploi De L'Ivermectine Pour Lutter Contre La Gale Sarcoptique Des Chevres En Indonesie
Résumé Les auteurs rapportent les résultats de 3 expériences ayant pour but la lutte contre la gale sarcoptique en Indonésie.Expérience n° 1: le traitement à l'ivermectine à la dose de 200 mg par kg de poids vif ou au coumaphos (bain en solution à 0,05 p. 100) a entraîné une réduction significative du nombre des parasites et un accroissement du poids corporel. Chez les témoins non traités au contraire, tous les animaux ont dû être retirés de l'expérience en raison de la sévérité de l'infection.Expérience n° 2: 3 niveaux de traitment par l'ivermectine ont montré une efficacité identique dans la réduction du nombre des acariens, tandis que là encore les animaux témoins non-traités ont dû être retirés.Expérience n° 3: Elle a révélé une réduction significativement plus grande dans le nombre des parasites après 2 doses d'ivermectine à sept jours d'intervalle, comparée à une dose unique. Comme dans les 2 expériences précédentes, la majorité des témoins a dû être soustraite au protocole. Les stratégies de lutte possibles et les raisons des échecs dans l'élimination des parasites font l'objet de la discussion.


Name and address for reprints: Dr A.J. Wilson, Project Manager, RIVS, PO Box 52, Bogor, West Java, Indonesia.  相似文献   
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Parmacokinetics of penicillin G was determined for the turkey. The study was prompted by the isolation of a sulfonamide-resistant strain of Pasteurella multocida from tissues of turkeys involved in an outbreak of fowl cholera and the subsequent discovery that little pharmacologic information was available concerning other antimicrobial agents in that species. Penicillin G was chosen for study because P multocida is susceptible to this antibiotic. The elimination of the antibiotic followed first-order kinetics, and the half-life was found to be 0.5 hours. Parenteral administration of benzathine-procaine penicillin G resulted in higher concentrations, which persisted for longer periods than did procaine or potassium salts of the antibiotic.  相似文献   
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To date, proteins isolated from the surface of the gut of gastrointestinal nematodes, particularly Haemonchus contortus, have generally proved to be useful protective antigens and several are being progressed towards recombinant protein-based vaccines. This paper describes the properties of some of the most promising antigens and summarises their performance in laboratory and field based trials. The antigens described include contortin, H11, H-gal-GP, GPI and cysteine proteinases. In addition, the discussion addresses the utility of selected antigens to protect against co-infecting nematode species such as Teladorsagia circumcincta and against related nematode infections such as Ostertagia ostertagi in cattle.  相似文献   
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Because preharvest sprouting decreases quantity and quality of wheat grain, researchers need effective protocols to assess response to preharvest sprouting conditions. The aim of this study was to determine which temperature gives the greatest difference in seed germination and expression of seed dormancy in 10 spring wheat genotypes. The genotypes were grown in the field near Swift Current, Saskatchewan in 2000 in a randomized complete block with four replicates. Seed samples were harvested at approximately 25% moisture content (wet weight basis) and dried to 12% moisture content with minimal after-ripening. Germination was under controlled environment at temperatures of 10, 15, 20 and 30 °C in darkness. A weighted germination index (WGI) was calculated. The analysis of WGI, for each temperature, showed highly significant (p ≤ 0.01) genotype effects on germination. Most genotypes decreased in WGI (increased dormancy) as temperature was increased from 10 to 30 °C. The greatest differences in seed germination tended to be at 15 °C and 20 °C. The level of seed dormancy depended on the genotype and germination temperature. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
60.
Wheat functions as a complex well-integrated organism with adaptation to many environments. Traits of wheat may be correlated to each other in a positive or a negative manner. The direction of the correlation is independent of breeding objectives and may change from one production environment to another. Grain yield is correlated positively with time to maturity in environments without terminal stress. The negative correlation between grain yield and grain protein concentration exemplifies an undesirable relationship in a wheat quality type in which protein concentration is positively correlated with bread loaf volume. However, this same correlation has an advantage to those end-products that are favored by low protein concentration such as confectionary products. To shift the negative correlation between grain yield and protein concentration requires assembling a more photosynthetically efficient, nitrogen-use efficient and\or water-use efficient genotype in combination or separately. Simultaneous selection for quantitative and quality traits is a breeding strategy, which with the inclusion of marker assisted selection, can shift undesirable correlations.  相似文献   
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