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121.
Fucoxanthin, belonging to the xanthophyll class of carotenoids, is a natural antioxidant pigment of marine algae, including brown macroalgae and diatoms. It represents 10% of the total carotenoids in nature. The plethora of scientific evidence supports the potential benefits of nutraceutical and pharmaceutical uses of fucoxanthin for boosting human health and disease management. Due to its unique chemical structure and action as a single compound with multi-targets of health effects, it has attracted mounting attention from the scientific community, resulting in an escalated number of scientific publications from January 2017 to February 2022. Fucoxanthin has remained the most popular option for anti-cancer and anti-tumor activity, followed by protection against inflammatory, oxidative stress-related, nervous system, obesity, hepatic, diabetic, kidney, cardiac, skin, respiratory and microbial diseases, in a variety of model systems. Despite much pharmacological evidence from in vitro and in vivo findings, fucoxanthin in clinical research is still not satisfactory, because only one clinical study on obesity management was reported in the last five years. Additionally, pharmacokinetics, safety, toxicity, functional stability, and clinical perspective of fucoxanthin are substantially addressed. Nevertheless, fucoxanthin and its derivatives are shown to be safe, non-toxic, and readily available upon administration. This review will provide pharmacological insights into fucoxanthin, underlying the diverse molecular mechanisms of health benefits. However, it requires more activity-oriented translational research in humans before it can be used as a multi-target drug.  相似文献   
122.
The effect of short term starvation on the disposition kinetics of chloramphenicol was determined in goats. The same dosage level (10 mg kg-1) administered intravenously produced higher serum concentrations in the animals when they were starved than when they were not starved. This could be attributed to the significantly smaller (P less than 0.05) volume of the central compartment. Starvation significantly decreased the rate of elimination of chloramphenicol while the apparent volume of distribution of the drug was not altered. A significant decrease in the body clearance, 1.36 +/- 0.95 ml (min kg)-1 in the starved condition compared with 3.78 +/- 2.19 mg (min kg)-1 in the controls, caused a corresponding increase in the half life of chloramphenicol. The decreased rate of elimination was attributed to decreased hepatic microsomal metabolism since starvation did not change the fraction of the dose excreted unchanged in the urine. The clinical significance of the altered disposition of chloramphenicol is that administration at the usual dosing rate would lead to accumulation of the drug and eventual toxicity.  相似文献   
123.
Summary A practical programme for control of ovine brucellosis in a Najdi sheep flock at Haradh and protection of sheep handlers from infection was implemented. Haradh sheep were serologically tested three times at six-month intervals. Of 2,721 sheep subjected to the first test, 387 (14.2%) were positive reactors. At the second test 2,072 sheep were tested and 31 (1.5%) were positive. The third test was performed on 2,963 sheep and only nine (0.3%) positive reactors were found. Of eight sheep handlers six had Malta fever. Positive reactor sheep were slaughtered and buried after each test. Following the third test all negative sheep were vaccinated with inactivatedBrucella melitensis vaccine. Infected sheep handlers were treated at the Haradh clinic. One year after completion of the programme abortions and infertility problems had disappeared and the lambing percentage had increased from 0.8 to 1.3 lambs per ewe. In addition all young lambs born to vaccinated ewes were found to be serologically negative. We suggest expansion of the present programme into a national brucellosis control campaign in the kingdom.
Control De Brucelosis Ovina En Ovejas Najdi En Arabia Saudita
Resumen Se implementó un programa práctico, para el control de brucelosis ovina en ovejas Najdi en Haradh, y para proteger a los pastores. Las ovejas se analizaron serológicamente tres veces con intervalos de seis meses. De 2.721 ovejas analizadas la primera vez, 387 (14.2%) dieron resultados positivos. La segunda vez, se analizaron los sueros de 2.072 ovejas, de las cuales 31 (1.5%) fueron positivas. El tercer analisis se realizo en 2.963 ovejas de la cuales solo nueve (0.3%) se detectaron como reactores positivos. De ocho pastores, seis tenían fiebre de Malta. Las ovejas positivas fueron eliminadas después de cada prueba serológica. Seguidamente, después de la tercera prueba, todas las ovejas negativas se vacunaron con la vacuna inactivada deBrucella melitensis. Los pastores enfermos, fueron hospitalizados. Un año después de la campaña, los problemas de aborto e infertilidad habían desaparecido, y el porcentaje de nacimientos se incrementó de 0.8 a 1.3 corderos por oveja. Más aún, todos los corderos nacidos de madres vacunadas fueron negativos serológicamente. Nosotros sugerimos la expansión del presente programa de control de brucelosis, a todo el Reino.

Lutte Conter La Brucellose Ovine Chez Des Moutons Najdi En Arabie Saoudite
Résumé Un programme pratique de lutte contre la brucellose ovine dans un troupeau de moutons Najdi à Haradh et de protection des éleveurs contre l'infection a été mis en oeuvre. Les moutons de Haradh ont été testés sérologiquement trois fois à six mois d'intervalle. Sur 2 721 moutons soumis au premier test, 387 (14,2 p. 100) ont réagi positivement; sur 2 072 moutons, au second test, 31 (1,5 p. 100); et sur 2 963 moutons, au troisième test, seulement 0,3 p. 100. Sur huit éleveurs de moutons, six étaient atteints de fièvre de Malte. Les moutons ayant réagi positivement ont été abattus et enterrés après chaque test. Après le troisième test, tous les animaux négatifs ont été vaccinés avec un vaccin àBrucella melitensis inactivé. Les éleveurs ont été soignés la clinique de Haradh. Un an après la fin du programme, les avortements et les problèmes d'infertilité avaient disparu et le pourcentage d'agnelages avait augmenté de 0,8 à 1,3 agneau par brebis. De plus, tous les jeunes agneaux nés de mères vaccinées étaient sérologiquement négatifs. L'extension de ce programme en une campagne de lutte nationale est préconisée.
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124.
Summary Pleuropneumonia of goats and sheep has been known to cause serious economic losses in many countries including Saudi Arabia. A preliminary investigation was carried out on 163 goats and 130 sheep which showed clinical symptoms or post-mortem lesions of pleuropneumonia. Pathological samples from the respiratory tract of live or slaughtered goats and sheep (183 and 160 samples respectively) were cultured for mycoplasmas. Of 343 mycoplasma cultures examined 211 (61·5%) isolates were characterised biochemically. A total of 116 isolates were serologically identified asM. mycoides subsp.mycoides, M. ovipneumonia, M. conjunctivae, M. agalactiae subsp.agalactiae, M. putrifaciens andM. arginini. The remaining mycoplasma isolates were not identified. The significance of the identified isolates and their probable pathogenic effect on the respiratory tract of goats and sheep are discussed. Their pathogenicity needs to be established experimentally before initiating a control programme in the Kingdom.
Resumen Se llevó a cabo una investigación preliminar en 163 cabras y 130 ovejas las cuales mostraron síntomas clínicos o lesiones postmortem de pleuroneumonía contagiosa. Se cultivaron en medios especiales muestras patológicas del tracto respiratorio de cabras y ovejas vivas (183 y 160 muestras respectivamente. De 343 cultivos examinados, 211 (61·5%) aislamientos se caracterizaron bioquímicamente. Un total de 116 aislamientos se caracterizaron serológicamente comoM. mycoides, subsp.mycoides, M. ovipneumonia, M. conjuntivae, M. agalactiae subsp.agalactiae, M. putrifaciens yM. arginini. Los restantes micoplasmas aislados no fueron identificados. Se discute el significado de los aislamientos identificados y su posible efecto patógeno en el tracto respiratorio de cabras y ovejas. Es necesario establecer la patogenicidad experimentalmente antes de iniciar un programa de control en el Reino.

Résumé On sait que la pleuropneumonie du mouton et de la chèvre cause de sérieuses pertes économiques dans beaucoup de pays, dont l'Arabie Saoudite. Une recherche préliminaire a été entreprise sur 163 chèvres et 130 moutons montrant des sympt?mes cliniques ou des lésions à l'autopsie. Des prélèvements du tractus respiratoire de chèvres et de moutons vivants ou abattus (respectivement 183 et 160 échantillons) ont été mis en culture pour la recherche de mycoplasmes. Sur les 343 cultures de mycoplasmes examinées, 211 souches (soit 61,5%) ont été caractérisées au point de vue biochimique. 116 souches ont pu être identifiées sérologiquement comme étantM. mycoides sub.mycoides, M. ovipneumoniae, M. conjunctivae, M. agalactiae sub.agalactiae, M. putrefaciens etM. arginini. Les autres souches de mycoplasmes n'ont pas été identifiées. La signification des souches identifiées et leur effet pathogène probable sur le tractus respiratoire des chèvres et des moutons sont discutés. Leur pouvoir pathogène demande à être expérimentalement établi avant de mettre en place un programme de contr?le de la maladie dans le Royaume.
  相似文献   
125.
This study was done to evaluate the estimated economic consequences of the recent discovery that an irradiated Schistosoma bovis vaccine was effective in reducing mortality and intensity of infection in cattle after field exposure to S. bovis in the White Nile province. The benefits and costs were hypothesized to occur over a 5-year period starting after the vaccine had been further developed to optimal commercial usefulness.

The potential benefits of vaccination are from the avoidance of mortality and growth delay losses caused by S. bovis infection and were based on an owner survey conducted in 1981. These benefits were discounted from the time of their potential marketing opportunity to the first year of a vaccination program at 15% per annum and were valued on a basis of 1982 prices for live cattle exported to Egypt and Saudi Arabia. Variations in benefits stem from degree of infection probability, mortality and morbidity estimates and percent of animals vaccinated. Since clinical schistosomiasis (“gorag” — sunken-eyed appearance) and associated production losses occur almost exclusively in 6- to 30-month-old cattle, and there is evidence for long-term immunity, vaccinations would be given to cattle in this age-specific group or younger once in their lifetime. The principal variation in vaccination program costs, also valued at 1982 prices, is from vaccine production costs; $0.50 or $4.00 per dose. A vaccine efficacy of 70%, observed in a previously reported field trial, was used in these calculations.

Present value benefit—cost (b–c) ratios were estimated for the central, western and southern areas for high- and low-level effects of S. bovis impact on production and the vaccination program, cost and effectiveness. In an area (central provinces) of high infection probability (90%), high percentage of animals vaccinated (90%), high mortality (7.1%), and low vaccine production costs, the b–c ratio was 12.7. In contrast, a b–c ratio of 0.7 was estimated for an area (southern provinces) assuming low infection probability (50%), low percent of animals vaccinated (50%), lower mortality (3.55%) and high vaccine production costs. Potential returns from increased future milk and calf production and from faster herd build-up with younger females were not included in these benefit calculations. These results indicate that under most conditions further development of the vaccine and cost-effective vaccine production techniques would yield very favorable returns from improved livestock production efficiency in the Sudan. Export prices were assumed to not vary significantly with increased supply of export-quality cattle resulting from the estimated production losses avoided by vaccination against schistosomiasis.  相似文献   

126.
The objective of the study was to compare sexual performance of pure and crossbred rams, and to evaluate whether prior exposure of rams to short-tailed females would enhance their mating ability when later exposed to fat-tailed females. Twenty-two virgin, yearling Awassi (A; n = 7), F1 Charollais × Awassi (CA; n = 7) and F1 Romanov × Awassi (RA; n = 8) rams were subjected to sexual performance tests on six 20-min occasions. Each ram was individually exposed to two short-tailed oestrous ewes for three 20-min occasions on three consecutive days. Following 1 day of rest, the same 3-day procedure was repeated for each ram with fat-tailed ewes. Leg kicking bout frequency increased in CA and RA rams and decreased in A rams, when they were exposed to fat-tailed compared with short-tailed ewes. No differences in anogenital sniffing were observed among rams exposed to either short-tailed or fat-tailed ewes. However, greater (p < 0.001) anogenital sniffing bouts were recorded, when rams were exposed to short-tailed females. Upon exposure to fat-tailed ewes, CA and RA rams experienced a marked increase in mounting frequency compared with a slight increase in mounting of A rams (p < 0.001). The ability of Awassi rams to raise the fat tail of Awassi ewes was greater (p < 0.001) than CA and RA rams. Mating was improved in A while declining in CA and RA, when they were exposed to fat-tailed compared with short-tailed ewes (p < 0.001). Based on the results of the current study, it seems that all yearling rams were capable of mating with short-tailed ewes, whereas only Awassi rams managed to mate with fat-tailed ewes. It appears that brief exposures of yearling crossbred rams to short-tailed ewes do not improve their mating ability when later exposed to fat-tailed ewes.  相似文献   
127.
During summer season, increase in the environmental temperature in the subtropical regions of Pakistan is negatively affecting the performance of dairy animals. The study objective was to determine the effect of ambient management (90 days) on productive and physiological performance of lactating Sahiwal cows during hot dry summer season. Fifteen lactating cows during the early lactation stage, having similar parity (3), daily milk production (6.2 l), were randomly allocated to three treatments, 5 cows each, i.e., (1) kept under roof shade only, (2) provision of fans along with roof shade, and (3) provision of roof shade, fans, and sprinklers designated as S, SF, and SFS, respectively. The fans were of 360-rpm capacity and showers were on for 40 min after every 90-min interval from 9:00 to 21:00 h. THI values were 81.1?±?0.7, 80.5?±?0.7, and 77.7?±?0.4 under S, SF, and SFS treatments, respectively. Cows were milked twice daily. Respiration rate (RR) and rectal temperature (RT) data were collected at 14:00 h on daily basis. The daily milk production was significantly higher in cows under SF (7.9?±?1 kg) followed by SFS (6.9?±?1.2 kg) and S (6.1?±?0.9 kg) treatments. The mean RT (101.0?±?0.04 °F) was significantly lower in cows under SFS than that on SF and S treatments and similarly mean RR was also lower (21.2 breaths/min) in cows under SFS followed by SF and S treatments. It is concluded that milk production and physiological performance in Sahiwal cows can be improved by fan-assisted ventilation during hot dry summer in subtropical regions.  相似文献   
128.
129.
Tropical Animal Health and Production - In tropical countries, one of the major threats for diary animal production is climate change. Ambient management interventions are beneficial and are the...  相似文献   
130.
The disposition kinetics and cumulative urinary excretion of sulfamethazine were compared in goats fed normally (control) and following a 72-hour period of starvation (fasting). The only pharmacokinetic parameter which showed a statistically significant difference between the two groups was the body (systemic) clearance. This decreased from 2.26±0.28 ml/min· kg ( ±SD, n=6) in the control group to 1.16±0.54 ml/min·kg in the fasting group (p<0.01). Since the apparent volume of distribution was not affected by starvation, the decreased clearance was attributed to slower metabolism of the drug. Because of the analytical method used to measure sulfamethazine concentrations in plasma and urine, no conclusion could be drawn as to whether the rates of hydroxylation or of acetylation, or both metabolic pathways were decreased in the starved condition.  相似文献   
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