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991.
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993.
Contents: Uterine activity, i.e. myometrial contractions, were recorded in 11 sows prior to and during parturition by using strain gauges placed onto uterine horns about 15 to 20 cm cranial of the bifurcation. Tocographic patterns observed prior to and during spontaneous and alfaprostol induced parturitions were normal. Administration of 20, 10 or 5 I.U. oxytocin 22 hours after alfaprostol quickly initiated abnormal periparturient contraction patterns with 20 and 10 I.U. oxytocin and in one of two animals receiving 5 I. U. These were characterized initially by prolonged tetanic contractions resulting in delayed deliveries, and later by the premature occurrence of patterns seen normally only during the phase of placental expulsions, although not all piglets had been delivered. The importance to use myornetrial activity profiles to evaluate parturition induction methods was stressed .  相似文献   
994.
Prolonged luteal activity is one of the most formidable terminology challenges in mare reproductive biology. Prolonged luteal activity can be a result of persistence of an individual corpus luteum or the sequential development of luteal glands, each of which may have a normal life span. Luteal tissue can originate from an unovulated follicle or from an ovulation occurring during either follicular or luteal dominance. These complexities, together with ambiguous and inconsistent terminology, have resulted in confusion regarding those conditions which can be grouped broadly under the term prolonged luteal activity. Persistence of an individual corpus luteum can occur in association with severe damage to the endometrium resulting in loss of the uterine luteolytic mechanism. Spontaneous (no known uterine pathology) persistence of the corpus luteum from the follicular-phase ovulation has not been documented adequately as a clinical entity. The occurrence of ovulation towards the end of dioestrus may cause confusion about the origin of prolonged luteal activity. Such immature dioestrous corpora lutea may not respond to the release of uterine luteolysin, thereby leading to prolonged luteal activity even though the original corpus luteum regressed at the normal time. In the absence of critical monitoring of the corpus luteum (eg by ultrasound) the prolonged activity could be attributed erroneously to persistence of the corpus luteum from the follicular-phase ovulation. Pseudopregnancy is another confusing term that is sometimes used to describe persistence of the corpus luteum, especially when the luteal persistence is caused by embryonic loss after the embryo has blocked the uterine luteolytic mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
995.
The occurrence of infectious bursal disease (IBD) in industrial poultry flocks in Cameroon was investigated by serological and virological techniques. Antibody to IBD virus was detected in 118 (33.9%) out of 348 serum samples collected in seven randomly selected areas. On the other hand, virological examination was performed on bursa of Fabricius samples obtained post-mortem from flocks in which there was a high mortality among young birds. This virological examination revealed the presence of IBD virus antigen. These observations confirm the occurrence of infectious bursal disease in Cameronian industrial poultry flocks.  相似文献   
996.
A case study focusing on the socio-economic and ecological aspects of a forest-based village, Debrasai, in the Singhbhum District of Bihar, India was undertaken in 1980 to evolve village-specific community forestry package programmes that could bring stability to the village both economically as well as ecologically. The village extending over 365.07 ha is inhabited by 361 people comprising 195 males and 166 females in 81 households. The villagers are by and large dependent on agriculture and forestry for their livelihood. The largest proportion of the land in the village is under agriculture whereas forests, in a highly degraded state, occupy only 5.7% of the total area. The villagers exploit the protected forests in their vicinity removing nearly 350.9 mt of fuelwood, 22.8 mt of small timber and 393.4 mt of fodder annually.The village has a manpower potential of 40 035 man days a year. Agriculture is the main source of employment at the moment absorbing 14 266 man days. The non-agricultural sector provides employment to an extent of 4433 man days. Fresh employment opportunities are needed to absorb nearly 53% of man days of the village at present unused. Three land-resource, skill-based package programmes, a tasar silk culture, an energy plantation, and dairying have been suggested to generate employment opportunities and to meet the basic needs of the villagers. About 115 ha of the hitherto neglected land resource has been located in the village to sustain such community forestry (CF) programmes. Tasar culture suggested on 35 ha will alone generate employment to an extent of 18 690 man days from the fourth year of tasar silk plantation. A plantation, to provide energy and fodder, on 25 and 30 ha respectively is expected to yield fuelwood, timber and fodder to more than satisfy village needs. A dairy has been recommended as it will generate income, provide nutrition and promote gobar gas production — an alternative energy source to fuelwood. The cost—benefit analysis of these projects indicates their economic feasibility with the cost likely to be recovered in 4.5 years. Debrasai being an agricultural village, a land-inequity compensatory scheme has been suggested for CF project net benefit sharing, ensuring reasonable benefit flows to the landless and marginal farmers.  相似文献   
997.
This review summarizes information on the clinical signs, gross and microscopic lesions associated with nematode and cestode infections and discusses the development of these conditions in the equine host.  相似文献   
998.
999.
ENTOMOLOGY     
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1000.
Two groups of 12 and 6 rats were inoculated with Fasciola hepatica and Schistosoma mansoni, respectively. The Schistosoma-inoculated group, as well as 6 Fasciola-inoculated rats and 6 uninfected rats were challenged 8 weeks later with F. hepatica. A control group of 6 rats was left unexposed. Eight weeks after the challenge exposure all rats were necropsied and subjected to post-mortem examination. The number of Fasciola recovered after challenge was lower in both groups of rats primarily infected with F. hepatica or S. mansoni. F. hepatica-induced pathological changes were observed in all infected rats, but were pronounced in the group which was first exposed at the time of challenge of the primarily infected groups. No Schistosoma eggs or adults were detected in Schistosoma-inoculated rats. The results demonstrated that rats primarily infected with F. hepatica acquired resistance against a challenge exposure to the homologous parasite. Also S. mansoni, even without patency, can provide partial protection against F. hepatica infection.  相似文献   
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