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1.
Experimental infection of Black Belly and INRA 401 straight and crossbred sheep with trichostrongyle nematode parasites 总被引:1,自引:0,他引:1
Gruner L Aumont G Getachew T Brunel JC Pery C Cognié Y Guérin Y 《Veterinary parasitology》2003,116(3):239-249
Compared to INRA 401 lambs reared in France, Black Belly (BB) lambs reared in Guadeloupe (F.W.I.) were highly resistant to both primary and secondary experimental infection with Haemonchus contortus. To investigate this huge inter-breed difference, a nucleus flock of BB was constituted, and experiments were conducted to: (i) confirm this difference in lambs born in France, (ii) check whether it was similar for Trichostrongylus colubriformis and Teladorsagia circumcincta, and (iii) find out whether this difference was age-related. Forty BB lambs, 84 F1 lambs (BB siresxINRA 401 ewes) and 88 INRA 401 lambs born in two cohorts were used in an experimental design involving three host breeds, both genders and two age-groups (3.5- and 7-month-old when first infected). The limited availability of BB lambs made the study incomplete. Infection consisted of the administration of two doses of 10,000 infective larvae of one of the nematode species, separated by an anthelmintic treatment and an interval of 1 week before the second dose was administered. Fecal egg counts (FECs) were done on Days 28 and 35 after each infection; ewe lambs of the INRA 401 and F1 breeds were necropsied, the worm burden was established, the length of the female worms measured and the eggs in utero counted. For H. contortus and T. colubriformis, the FEC was lower in the BB than in the INRA 401 lambs, and the FEC found for the F1 lambs was intermediate. For T. circumcincta, only data for the F1 and INRA 401 lambs were available, and the FECs for these breeds were the same. In all three breeds, the FEC determined after the second dose was significantly lower than that found after the first dose in the ewe lambs, but not in the ram lambs. Infecting the lambs when they were 7- instead of 3.5-month-old significantly lowered egg excretion of both parasites in the F1 (P<0.0001), but not the INRA 401 lambs. Worm numbers in the F1 and in the INRA 401 ewe lambs confirmed the FEC data, many F1 lambs being free of T. colubriformis. The H. contortus female worms were shorter and had fewer eggs in utero in the F1 than in the INRA 401 lambs. A higher proportion of T. circumcincta was at the fourth larval stage in the F1 lambs. In conclusion, the BB breed is much more resistant than INRA 401 to H. contortus, with the F1 lambs being more like the BBs after the second dose. This difference was also found for T. colubriformis and, to a lesser extent, for T. circumcincta. 相似文献
2.
The experiment was conducted to determine the supplementary feeding value of ground Prosopis juliflora pod (Pjp) and cottonseed meal (CSM) and their mixtures on feed intake, body weight gain and carcass parameters of Afar sheep fed a basal diet of pasture hay. Twenty-five yearling fat-tailed Afar rams with mean initial live weight 17.24?±?1.76 kg (mean ± SD) were used in a randomized complete block design. Animals were blocked on their initial body weight. The experiment was conducted for 12 weeks and carcass evaluation followed. Treatments were hay alone ad libitum (T 1) or with 300 g CSM (T 2), 300 g Pjp (T 5), 2:1 ratio (T 3) and 1:2 ratio of CSM : Pjp (T 4). The CP contents of the hay, CSM and Pjp were 10.5, 44.5 and 16.7 %, respectively. Hay DM intake was higher (P?<?0.05) for non-supplemented and total DM intake was lower in non-supplemented. Average daily weight gain (ADG) was lower (P?<?0.05) for T 1 compared to all supplemented treatments except T 5. Hot carcass weight and rib-eye muscle area also followed the same trend like that of ADG. Compared with feeding hay alone, supplementing with CSM or a mixture of CSM and Pjp appeared to be a better feeding strategy, biologically, for yearling Afar rams. 相似文献
3.
Summary Up to 100 single plant derived lines of 18 Ethiopian barley landraces were evaluated for infection type in the seedling and adult plant stage, and for latent period in the adult plant stage only. A low infection type indicates the presence of race-specific resistance genes of the hypersensitive type, while the latent period is the major component of the polygenic, partial resistance.In the seedling stage 1721 of these single plant derived landrace lines were assessed for infection type against two barley leaf rust races. In the adult plant stage 1227 from these 1721 lines were evaluated for infection type against one race. In the seedling stage 2 (against race 1-2-1) and 29 against race A) out of the 1721 lines showed an infection type lower than 6–7 on the 0 to 9 scale. In the adult plant stage none of the 1227 lines had an infection type lower than 6–7 against race 1-2-1.The variation between and within the landraces for latent period in the adult plant stage was large. Some landraces such as landrace 212845 showed a highly significant and longer mean latent period than most other landraces. Virtually all plants in all landraces carry at least some partial resistance.The near-absence of race-specific, major, resistance genes and the high frequency of moderate levels of partial resistance indicates that the durability of leaf rust resistance in Ethiopian barley landraces is due to the latter type of resistance, and that the multiline principle does not operate. 相似文献
4.
Getachew Belay T. Tesemma E. Bechere D. Mitiku 《Genetic Resources and Crop Evolution》1995,42(4):387-391
Summary Purple-grain tetraploid wheats (Triticum turgidum L.) are widely cultivated in the Ethiopian highlands despite the claim that they have lower industrial quality properties
and market prices than the white or red/brown seed-colour types. In an attempt to find a possible explanation for this, the
three seed-colour groups were compared for grain yield, other 11 agronomic traits and protein content. Five traits displayed
significant differences between seed colour groups where the purple-seed was superior; earlier maturity, shorter height, and
higher fertility, tillering capacity and harvest index. Most of these are important adaptive traits to waterlogging stress
on dark-clay soils (pellic vertisols) where the great bulk of the Ethiopian tetraploid wheats have been grown. Furthermore,
among the three seed-colour groups, purple-seed wheat has the best malting quality for the preparation of arekie, a locally
distilled spirituous liquor. It, therefore, appears that both natural and human selections have been reponsible for their
continued cultivation. Hence, the notion that purple-seeded wheat is the “least preferred” should be interpreted carefully
not to necessarily address the whole community in Ethiopia. As to their taxonomy, all tetraploid wheat taxa (T. turgidum L. sensu lato, 2n = 4x = 28) that are found in Ethiopia, with the possible exception of T. dicoccon Shrank (locally known
as Adja), may possess the purple pericarp-colour, although in varying frequencies; very low inT. polonicum L., and high inT. carthlicum Nevski andT. durum Desf. 相似文献
5.
Getachew AM Innocent G Trawford AF Reid SW Love S 《Tropical animal health and production》2012,44(4):757-762
A retrospective study was conducted to investigate the cause of rectal prolapse in working donkeys in Ethiopia. Analysis of
data on rectal prolapse cases obtained from the Donkey Health and Welfare Project clinic at the School of Veterinary Medicine,
Addis Ababa University, from 1995 to 2004 revealed that 83.6% (n = 177) of the cases were associated with Gasterophilus nasalis. The rest 10.7% and 5.7% were associated with work-related (overloading) cause and diarrhoea, respectively. The mean and
median numbers of G. nasalis recovered from the rectum of infected donkeys were 66 and 64, respectively, with a range of 2–195. Over 100 G. nasalis larvae were recovered from the rectum of 22% of the donkeys. Circular demarcated ulcer-like and deep circumferential pits
or ring-like mucosal lesions were found at the larval attachment sites. G. nasalis infection and the associated rectal prolapse were observed year round. However, the intensity of rectal larval infection
and incidence of rectal prolapse were significantly higher during the rainy season (P < 0.01). Age and sex of the donkeys had no significant effect on the intensity of rectal larval infection and incidence of
rectal prolapse (P > 0.05). 相似文献
6.
Collective action, on communal grazing land, has evolved in the highlands of northwestern Ethiopia to mitigate the problems of feed shortage and land degradation due to overgrazing. The exercise is liked by farmers for improving the availability of natural pasture during the long dry season when other feed sources get depleted. However, large portions of the communal grazing lands are still managed under free grazing throughout the year. This study was undertaken in Maynet village in the upper Blue Nile basin, northwestern Ethiopia, to assess the impacts of three different types of grazing land management (GLM) and two slope gradients (<10%; 15–25%) on aboveground herbaceous biomass yield, ground cover, species richness, runoff, soil loss and soil bulk density of grazing lands. The GLMs include (a) freely open communal GLM, (b) restricted communal GLM – collective management of communal grazing land locally named as ‘yebere sar’ and (c) private holding GLM. Stocking density was more than carrying capacity of grazing lands across all GLMs. However, the extent of overstocking problem was exceptionally severe in freely open communal GLM. The interaction between GLM and slope was significant (P<0.05) for runoff, soil loss and runoff coefficient. The average runoff coefficient was close to 50% in freely open communal GLM on steeper slopes (15–25%). Freely open communal GLM on steeper slopes resulted in consistently highest cumulative runoff and soil loss amounting to 491 mm and 32 t/ha per year, respectively. Polynomial regression analysis showed that quadratic relationship (r2=0.87) existed between soil loss and runoff. But, soil loss was close to nil when runoff did not exceed 2 mm per rainfall event. As expected, restricted communal GLM appeared to reduce surface runoff by more than 40% and curb the rate of soil erosion by more than 50% compared to freely open communal GLM. Its vegetation cover persisted above 70% throughout the year, meeting the threshold level recommended to keep surface runoff and soil loss to minimum. Reducing the problem of overstocking and pasture resting in August–November are important components to improve ground cover and aboveground herbaceous biomass yield, which in turn reduce land degradation on grazing lands. 相似文献
7.
Bekele MEGERSA Alemayehu REGASSA Bersissa KUMSA Fufa ABUNNA 《Animal Science Journal》2008,79(4):534-541
The aim of the present study was to investigate the performances of camels kept by pastoralists with different degrees of experience in camel production. The study was conducted on 60 selected camel herds twice a year; during wet and dry seasons of 2003 and 2004 in Borana, Southern Ethiopia. The average ages at first parturition and calving intervals of breeding females were 68.1 ± 0.5 and 25.5 ± 0.4 months (LSMean ± SE), respectively. Age at first parturition was significantly reduced by use of veterinary services, while variation was not observed among Borana, Guji, Gabra and Somali herds. Calving intervals were significantly shorter (P < 0.05) in Borana (24.8 ± 0.6) and Guji (24.5 ± 1.5) than Somali herds (27.0 ± 0.5). Calving intervals were also prolonged (P < 0.05) by fixing breeding time. Annual calving, abortion and calf mortality rates were similar for the four populations and averaged 37.3%, 9.3%, 20.3% in 2003, and 41.3%, 8.2%, 14.9% in 2004, respectively. The overall mortality rate was significantly higher (P < 0.05) in Borana (10.0 ± 2.1) than in Gabra herds (4.2 ± 0.8). However, mortality was not statistically different for use of veterinary services and other managemental practices. The study showed an increase in annual herd growth by 5.7% in 2003 and 11.6% in 2004 with similarity of herd dynamics between the two years. Daily milk yield differed significantly (P < 0.05) depending on veterinary services, watering frequency and the season (7.6 L during wet and 4.3 L during dry season). Similarly, milk yield was significantly higher (P < 0.01) in Somali herds than in Borana and Gabra herds. In conclusion, the study revealed that some production and reproduction performances in camel herds have showed significant variation with varying levels of herding experience and veterinary services. This may suggest performance in pastoral camels can be enhanced with learning more about and using traditional management practices as well as improving animal health service delivery. 相似文献
8.
Aynalem Haile Solomon Gizaw Tesfaye Getachew Joaquín P. Mueller Peter Amer Mourad Rekik Barbara Rischkowsky 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(5):319-328
Ethiopia has a large and diverse population of small ruminants, which contribute substantially to the livelihood and income of the rural poor and the country at large. However, the sector faces a number of challenges. Productivity per animal and flock offtake are both very low. Reasons attributed for the apparent low productivity are as follows: absence of appropriate breeding programmes, lack of technical capacity, inadequate and poor‐quality feeds, diseases leading to high lamb mortality, and underdeveloped markets in terms of infrastructure and information. Historically, sheep and goats have received little policy or investment attention. Genetic improvement of small ruminants could contribute to bridging the productivity gap. In the past, the government of Ethiopia has placed much emphasis on importing exotic genetics and cross‐breeding with local stock as a strategy for genetic improvement. However, this has not led to a significant productivity improvement and the programmes have generally been unsustainable. Currently, there is a change in approach and a recognition of the need to focus genetic improvement efforts on the local genetic resources that are well adapted to the diverse agro‐ecologies and production environments in the country. Community‐based breeding programmes (CBBPs), which focus on indigenous stock and consider farmers’ needs, views, decisions and active participation, from inception through to implementation, have been identified as programmes of choice. The Ethiopian government and the private sector need to invest in strategic areas around CBBPs to make the programme work for the poor and be sustainable in low‐input systems. 相似文献
9.
A possible way out of the ‘low-level equilibrium trap’ in the Ethiopian Highlands is agricultural intensification. To characterise and quantify current transformations in these permanent upland cultivation systems, a detailed study on land use changes and its proximate causes was carried out in the 41 km2 Bela-Welleh catchment (2050–3682 m a.s.l.) in the Wag zone of Amhara Region, Northern Ethiopia. Land use maps were obtained through aerial photo interpretation (1965 and 1986) and detailed field mapping (2005–2006). Interpretation of topographic maps and field mapping gave knowledge of the spatial distribution of possible explanatory factors. Major land use changes are (1) a gradual abandonment of mountain agriculture which was replaced by woody vegetation (now covering 70% of the upper catchment) and (2) the widespread introduction of irrigation agriculture, wherever water is available (from 0% in 1982 to 5% of the catchment in 2006). Whereas both changes are favoured by government policies, they have now at least partially been taken up by the farming communities. The study demonstrates these land use changes and their influencing factors. Changes of crop- and rangeland into forest occur on the steeper slopes in higher topographical position. Changes from rain fed cropland into irrigated cropland (two harvests) depend obviously on the availability of water, but also on population density, and inversely on distance to Sekota town. We are here in presence of an almost classical example of the mutation of a “permanent upland cultivation system” into a system with irrigated agriculture. 相似文献
10.
The study was carried out from July 2007 to June 2008 in Wolaita Sodo Abattoir to assess the status of hydatidosis in cattle.
Routine meat inspection, hydatid cyst count and characterization were conducted. Out of 400 cattle slaughtered in Wolaita
Sodo Abattoir 64 (16%) animals were found harboring hydatid cysts. Thorough meat inspection in the abattoir revealed that
74 visceral organ were found harboring one or more hydatid cysts. The infection of the lung, liver, spleen and kidney were
found to be 45.94% 45.94%, 6.75% and 1.35% respectively. From the total of 283 hydatid cysts counted 153(54.06%), 17(6.00%),
5(1.76%), 108(38.16%) were found to be small, medium, large and calcified cysts respectively and 170(60.28%), 5(1.76%) and
108(38.16%) were sterile, fertile and calcified cysts respectively. The rate of cyst calcification was higher in the liver
than in the lung while fertility rate was higher among the cysts of the lung. Hydatid cyst viability rate of 40% was observed. 相似文献