23 research outputs found
Cosmic ray neon, Wolf-Rayet stars, and the superbubble origin of galactic cosmic rays
The abundances of neon isotopes in the galactic cosmic rays (GCRs) are
reported using data from the Cosmic Ray Isotope Spectrometer (CRIS) aboard the
Advanced Composition Explorer (ACE). We compare our ACE-CRIS data for neon and
refractory isotope ratios, and data from other experiments, with recent results
from two-component Wolf-Rayet (WR) models. The three largest deviations of GCR
isotope ratios from solar-system ratios predicted by these models are indeed
present in the GCRs. Since WR stars are evolutionary products of OB stars, and
most OB stars exist in OB associations that form superbubbles, the good
agreement of these data with WR models suggests that superbubbles are the
likely source of at least a substantial fraction of GCRs.Comment: 22 pages, 6 figures Accepted for publication by Ap
Effect of trypanosome infection on livestock health and production traits in two areas of Togo
Presents data on the prevalence, species and intensity of trypanosome infection found in different livestock species, breeds, age groups and management systems for cattle and sheep in the Avetonou area and for sheep and goats in the sokode area, Togo. Evaluates the effect of these trypanosome infections on health and production traits in cattl
Economic aspects of recently introduced trypanotolerant livestock production under trypanosomiasis risk in southern Togo
Report of a study on the economics of trypanotolerant livestock production with station cattle and village cattle and sheep. Presents data on overall cattle & sheep production parameteres, economic parameters including veterinary services, veterinary treatments, fodder, mineral blocks, night kraul and herdomen. Gives the distribution & annual overall cost of production inputs per animal
Effect of trypanosome infection on livestock health and production in Togo
The prevalence, species and intensity of trypanosome parasitaemia in different livestock species, breeds, age groups and management systems are reported from Togo for trypanosotolerant sheep and goats in the Sokode area. The effects of these trypanosome parasitaemias on health and production traits in cattle and sheep are evaluated
Factors influencing reproductive performance in a range of network situations
The effects of trypanosome infection and of other factors on parturition interval were evaluated using records for parturitions, which occurred between January 1984 and December 1986 at the Network sites of Avetonu, Boundiali and Mushie. For Mushie some intervals, calculated using parturitions occurring in early 1987, were also included. Mean litter sizes of sheep at Avetonou and Boundiali were very similar, 1.15 and 1.18, respectively. In Boundiali but not in Avetonou, lambing interval was affected significantly (p<0.05) by trypanosome infection post-partum. Trypanosome infection pre-partum did not affect lambing interval at either site. Apart from the effect of year-season of parturition in Boundial, other systematic environmental effects were not significant sources of variation affecting lambing interval. The least square means for calving interval are 424 days at Avetonou (the shortest), 515 days at Mushie (the longest) and 488 days at Boundiali (intermediate). At each of the three sites cows with trypanosome infection post-partum had longer calving intervals that unaffected cows, but only reached significance (P<0.05) in Avetonou. At each of the sites there was a trend for shorter calving intervals with higher PCV. The effect reached statistical significance (p<0.01) at Mashie
Factors influencing reproductive performance in a range of network situations
Evaluates the effects of trypanosome infection and other factors on parturition interval (1984-1986) at Network sites of Avetonou, Boundiali & Mushie. Presents data on litter size, lambing interval and calving interval
Factors influencing liveweight in a range of network situations
The health and performance records of cattle and sheep used were collected over a three-year period, 1984-1986, at four network sites. Three of the sites, Avetonou (Togo), Boundiali (Cote d’Ivoire) and Mushie (Zaire) were chosen because of their high mean trypanosome of the live weight performance, and the fourth site, Kolo (Zaire), was chosen to give estimates of the liveweight performance of trypanotolerant cattle at zero trypanosomiasis risk. Trypanosome prevalence significantly depressed the live weight performance of N’Dama cattle at Mushie, but the effects at the other sites, although generally in the same direction as those at Mushie, did not reach statistical significance (p>0.05). At Mushie trypanosome infection of the N’Dama cow during gestation did not affect her parturition weight, but in the infection occurred during the last 3 months pre-partum then the birth weight of her calf was depressed significantly. The results relating PCV & live weight traits showed that a low PCV associated with poor live weight performance and a high PCV with better performance. Result from the Mushie, Kolo and Avetonou showed a positive relationship of mean PCV in the calf pre-weaning with pre-weaning growth and weaning weight. Trypanosome infection in the ewe, as measured by the number of parasitaemic months during gestation and/or lactation, did not depress her subsequent body weight, nor was there any cumulative effect of trypanosome infection pre and post-partum on ewe weight at weaning, nor on ewe weight change during the lactation, Similarly lamb weaning weight and lamb pre-weaning growth were not affected lamb weaning weight and lamb pre-weaning growth were not affected by one or more parasitaemic months in the ewe during lactation
Factors influencing liveweight in a range of network situations
Discusses factors influencing liveweight in a range of trypanotolerance network situations. Analyses liveweight traits, viz, dam liveweights at parturition and weaning, dam liveweight change between parturition and weaning, progeny liveweights at birth and weaning and progeny pre-weaning daily gain
Genetic and environmental factors affecting the epizootiology and pathogenesis of trypanosomiasis in livestock at eight sites within the African Trypanotolerant Livestock Network
Studies the influence of livestock species, breed, age and lactational status on the prevalence, species and intensity of trypanosome infection in livestock at eight sites of the African Trypanotolerant livestock network in west, Central, and East Africa. Estimates the effect of trypanosome infections on the blood packed cell volume (PCV) of cattle for four characters, average PCV during gestation, at parturition, pre-weaning and at weaning. Reports also the effects of trypanosome infections on livestock viability, reproductive performance and live weights