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41.
At the constant temperature of 25 degrees C and relative humidity (RH) of 84%, the average pre-oviposition period of Hyalomma lusitanicum was 47 days, the oviposition lasted an average of 26 days and the total egg production was an average of 6320 per female. At 16 degrees C the females did not lay eggs at all, but those which survived for 1 year and were transferred thereafter to 25 degrees C and 84% RH laid viable eggs. At 35 degrees C, the oviposition was identical at all levels of RH tested (25, 62 and 93%). At 25 degrees C, the pre-oviposition period was shorter at 93% RH, and the number of eggs laid was fewer at 25% RH. The eggs hatched in 32-40 days, the hatching percentage being lower in batches of eggs laid at the beginning and at the end of the oviposition period. The larval and nymphal moultings were not influenced by the type of host. As the temperature increased, the pre-moult period became shorter. The engorged larvae were more sensitive to the low RH than the engorged nymphs, whose moulting percentage was always greater than 72 in all regimes. Low temperature and high humidity had a favourable effect on the survival of unfed nymphs. The female-to-male ratio was 1:2. Hyalomma lusitanicum always behaved as a 3-host tick. The adults did not engorge on rabbits. The female ticks engorged on calves weighed an average 543 mg. Ticks maintained at 25 degrees C and 84% RH and engorged on calves completed the life cycle in 138-196 days, which does not include the period of chitinization of about 30 days. More than half of this period was spent in egg laying and hatching.  相似文献   
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Severe clinical balabtidiosis in 2-month old piglets was treated with acetarsol alone and acetorsol in combination with oxytetracycline. Three groups of 15 animals each were used in this trial. Group 1 received acetarsol at a dose rate of 20 mg/kg body weight orally once daily for 4 days. Group 2 received acetarsol as group 1 plus oxytetracycline at a dose rate of 15 mg/kg body weight orally in feed concentrate twice daily for 4 days. Group 3 animals served as non-treated controls. As judged by clinical and parasitological examinations, acetarsol was found to be 85.7% effective and the combination of acetarsol and oxytetracycline 100% effective. No sign of intolerance or toxicity was observed.  相似文献   
44.
Wild caught Asian catfish were spawned manually following HCG injection, and a portion of the eggs were subjected to cold-shock at 4 C for 15 min within 2-min post-fertilization. Nuclear diameter measurements of cold-shocked fish revealed that 96% were triploids (3N), while non-shocked fish were all diploids (2N). During larval and fry culture (first 26 d), triploid fish mortality was =50%, while diploid mortality was =25%. Following 8-mo culture in tanks at three stocking densities, triploid fish survival was significantly greater ( P < 0.05), than diploids, with 84.0% and 57.3%, respectively. Triploid live weight was also significantly greater than diploids, with 69.2 and 45.9 g averages, respectively. Ninety-two percent of diploids had welldeveloped gonads after 8 mo; whereas none of the triploids had mature gonads. Gonads were undifferentiated with 31% of the triploids. These sexually undifferentiated fish had greater growth rates than male or female triploids, and greater growth than all diploids. Carcass weight (gutted) of triploids was 95.8% of live weight, compared with 92.5% for diploids. Lastly, triploids had very few deformities compared with diploids, with 1.3% and 17.6%, respectively. Deformities included curved spines, and humped backs just posterior of the head.  相似文献   
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46.
Strongylus vulgaris populations in the cranial mesenteric arteries, caecum and colon were studied in 14 donkeys obtained from a communal area of the Zimbabwean highveld during July and November, 1986, and January and April 1987. Adult parasites were present in all animals and larvae in the cranial mesenteric arteries of 12 animals. Aged animals had high worm burdens. The number of adult parasites varied from 63 to 1255 (mean 382) and of larvae in the arteries from 0 to 181 (mean 69). The mean adult worm burdens were highest in July (400) and November (488), and lowest in April (107). The mean arterial larval burden was highest in July (130) and lowest in November (21). These observations indicate that infection with S. vulgaris takes place during the rainy season resulting in the heavy arterial larval population from January onwards and the heavy adult population during the dry season.  相似文献   
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48.
The agar gel precipitation test was used to detect rotavirus antibodies in the serum of 562 calves and bovine rotavirus antigen in the feces of 347 calves. Significantly more females had rotavirus antibodies in the serum (P less than 0.01) and rotavirus antigen in the feces (P less than 0.1) than did male calves. Female buffalo calves were also found to be more susceptible than male buffalo calves to rotavirus infection.  相似文献   
49.
Over two consecutive years, weekly examinations for the presence of nematodes were conducted on 185 stomachs from donkeys originating mainly from the Rabat, Casablanca and Settat regions of Morocco. All the animals, except one, were infected by at least one of four helminth species.Trichostrongylus axei was found in 93.5%,Habronema muscae in 89.7%,H. majus in 85.4% andDraschia megastoma in 1.1% of donkeys. Most animals were infected by two (23.8%) or three (71.9%) species. High burdens ofT. axei were observed in the winter of both years and in the mid-summer of the second year. Peak burdens ofHabronema were found at various times throughout both years. There were more adultH. majus thanH. muscae. The periods of peak levels of infection by these parasites were related to environmental conditions suitable for the development and survival of infective larvae ofT. axei and for the build-up of muscid fly vectors ofHabronema andDraschia spp.  相似文献   
50.
Summary The counterimmunoelectrophoresis (CIE) test was standardised for the detection of goat pox antigen and antibody using inactivated antigens. The chloroform inactivated and live antigens were equally sensitive for detection of goat pox precipitins. The precipitinogens of goat pox virus (GPV) were found to be soluble in nature. The CIE test was quick as well as more sensitive than the agar gel precipitation test for detection of GPV antibody/antigen. The CIE employing inactivated antigen has been used for the first time in the detection of GPV antibodies/antigens.
Deteccion Del Antigeno Y Anticuerpos De Viruela Caprina Mediate La Prueba De Contrainmunoelectroforesis
Resumen Se estandarizó la prueba de contrainmunoelectroforesis, para la detección del antígeno y anticuerpos del virus de la viruela caprina, usando antígenos inactivados. El antígeno inactivado con cloroformo y el antígeno vivo, fueron igualmente sensitivos para la detección de precipitinas de viruela caprina. Los precipitógenos del virus de la viruela caprina se encontraron que eran solubles. La prueba de contrainmunoelectroforesis fue más rápida y más sensitiva que la precipitación agar gelatina para la detección de anticuerpos/antígenos del virus de la viruela caprina. La prueba de contrainmunoelectroforesis con antígeno inactivado ha sido utilizada por vez primera en la detección de anticuerpos/antígenos del virus de la viruela caprina.

Detection De l'Antigene Et De l'Anticorps Variole Caprine Par Un Test De Contrimmuno-Electrophorese
Résumé Le test de contrimmuno-électrophorèse (CIE) a été standardisé pour la détection de l'antigène et de l'anticorps variole caprine avec des antigènes inactivés. Les antigènes vivants et inactivés par le chloroforme sont de sensibilité équivalente pour la détection des précipitines variole caprine. On a montré que ces précipitogènes du virus variole caprine (VVC) étaient de nature soluble. Le CIE est rapide et plus sensible que le test de précipitation en gélose pour la détection des antigènes et anticorps VVC. C'est la première fois que le CIE mettant en oeuvre un antigène inactivé a été utilisé.
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