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931.
G. Maffeo D. Vigo R. Ballabio O. Olivia F. Cairoli W. Jöchle 《Reproduction in domestic animals》1990,25(1):36-43
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
932.
Brilliant pigment powder was used to measure minimum gastrointestinal transit times (GTT) in control and cloned-reovirus-inoculated turkey poults. Compared with controls, inoculated poults had longer GTT at 120 hr (P less than 0.05) but not at 24 and 72 hr after receiving a single oral dose of cloned reovirus. Reovirus inoculation was associated with failure to eat following a fasting period. Feces passed by reovirus-inoculated turkeys were more fluid and less well formed than normal. 相似文献
933.
P T Oberem S R Van Amstel O Matthee J D Bezuidenhout 《The Onderstepoort journal of veterinary research》1985,52(4):283-287
Natural and experimental cases of sweating sickness were treated using a hyperimmune serum as specific treatment and hyperimmune serum combined with symptomatic and supportive treatment based on the clinicopathological changes observed in cases of sweating sickness. The treatment regimens were found to be highly effective in pigs and sheep as well as in calves, although recovery in the latter species was slower. 相似文献
934.
Chicks from lines selectively bred for either high or low antibody response post-primary immunization (PPI) to sheep erythrocytes (SRBC) and their reciprocal crosses were immunized intravenously with 0.1 ml of 0.25% SRBC antigen in Trials 1 and 3 and with 0.1 ml of 0.025%, 0.25%, or 25% SRBC antigen in Trial 2. All initial immunizations were made at 35 days of age, and 0.1 ml of 0.25% SRBC booster dose was given 24 days later. Results showed that (a) population differences appeared by day 4 PPI and persisted through day 24 PPI, (b) regardless of population, peak titers occurred at about the same time for primary and secondary immunizations, (c) dosage of antigen influenced differences among populations in antibody response to primary immunization, and (d) both selected lines had similar responses in 2-mercaptoethanol-sensitive and 2-mercaptoethanol-resistant antibodies to primary but not secondary immunization. 相似文献
935.
O F Pahnish J J Urick W C Burns W T Butts M Koger R L Blackwell 《Journal of animal science》1985,61(5):1146-1153
Genotype X environment interactions for postweaning performance traits of bulls produced by different lines of Hereford cattle were investigated in the contrasting environments of Miles City, Montana and Brooksville, Florida. During Phase 1 of the study (1966 to 1973), the performance of bull progeny from two unrelated lines (M1 and F6 previously developed in Montana and Florida, respectively) was compared at each of the two experimental sites. During Phase 2 (1967 to 1974), performance of bulls from two related lines (M1 of Montana origin and F4 derived from an M1 foundation through selection in Florida) was compared at each of the two locations. The line X location interaction effect in Phase 1 was highly significant for weaning weights and average daily gain during the postweaning test, and for end-of-test weight, conformation score, condition score and forecannon circumference. The interaction effect in Phase 2 was highly significant for 205-d and end-of-test weights and significant for all other traits except end-of-test conformation score. These results, consistent with results for traits covered in other papers of the same series (reproductive traits, birth-to-weaning traits of bull and heifer calves combined, and postweaning traits of heifers), indicated the existence of economically important genotype X environment interactions in beef cattle. Results from the series of papers indicated that adaptation to local environment should receive consideration in planning breeding programs, performance tests and interregional transfers of beef cattle. 相似文献
936.
O J Ginther 《Equine veterinary journal》1990,22(3):152-156
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
937.
938.
O. ANNEVILLE S. SOUISSI J. C. MOLINERO D. GERDEAUX 《Fisheries Management and Ecology》2009,16(6):492-500
Abstract Analysis of long-term catches from the deep peri-alpine Lake Geneva, showed a shift in the stock-recruitment relationship of Coregonus lavaretus (L.), a target species of commercial fishing. This change was mainly related to large-scale meteorological factors. Higher spring water temperatures may have improved larval survival and hence recruitment of whitefish via: (1) a better match between the hatching date of whitefish larvae and development of their zooplankton prey; and (2) the positive temperature effect on larval growth. In Lake Geneva, changes in regulatory mechanisms coupled with stocking and improved water-quality have led to an explosion in the C. lavaretus population in recent years. These results highlight the relevance of long-term changes in the stock-recruitment relationship for management of aquatic ecosystems that are sensitive to climate forcing. 相似文献
939.
Chicks infected with Salmonella typhimurium at 1 day of age were treated with normal intestinal flora starting 3 or 9 days later. Chicks were reared on the floor in isolated pens with wood shavings for litter. Cloacal-swab cultures were the main criteria for determining S. typhimurium infection. A single treatment reduced the infection period, but multiple treatments hastened the process considerably: after 6-8 weeks, birds given multiple treatments yielded sporadic or no isolations of S. typhimurium. It appears that litter from birds colonized by a protective microflora may serve as a vehicle for transmitting the flora to succeeding groups of birds. 相似文献
940.
O A Durojaiye P Kwenkam 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1990,43(4):439-440
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