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1.
Mekonnen S 《Journal of the South African Veterinary Association》2001,72(1):44-45
An aqueous emulsion of amitraz (Bovitraz, Bayer AH), prepared and applied according to the manufacturer's recommendations, was evaluated for its activity against cattle ticks on a dairy farm in Ethiopia. Eight crossbred heifer calves aged between 6 and 8 months and heavily infested with ticks were selected and divided into equal treatment and control groups. The calves in the treatment group were hand-sprayed with the amitraz emulsion while the control group was left untreated. Each calf was restrained and ticks were counted and identified in situ. One hundred percent tick control was achieved on Day 3 after acaricide application, and this was maintained for a further 18 days. The residual effect was long, and protected the animals from re-infestation for 21 days. There was a significant difference between the mean number of ticks on the control group compared to the treated group (P < 0.05). An important finding in this trial was the rapid detachment of all tick instars from animals treated with the test acaricide. 相似文献
2.
The study was conducted to examine the fertility status of crossbred dairy cows in mixed crop-livestock production (MCLP), market-oriented specialized dairy production (MSDP) and urban dairy production (UDP) systems, including the Holetta Agricultural Research Center (HARC). Data on general farm management variables and reproductive histories were collected from study farms by questionnaire and from individual cow records. Age at first service and age at first calving were 29.58 months (n = 424) and 40.6 months (n = 348), respectively. Cows managed under UDP were younger at first service and at first calving (p<0.05). The mean intervals from calving to first service and to conception were 141.98 days (n = 284) and 185.02 days (n = 219), respectively. The mean calving interval for cows was 551.82 days (n = 258). Cows in MCLP had longer intervals from calving to first service and to conception and longer calving intervals than those managed under MSDP, UDP and HARC. First service conception rate (43.42%), number of services per conception (1.75) and pregnancy rate (79.29%) did not differ significantly between production systems. Reproductive performance was best in UDP followed by HARC and MSDP. The difference between MCLP and the rest points to particular difficulties in that system. To improve reproductive performance and economic benefit, there should be conservative stocking rate, sensible year-round feeding, a herd health plan, and sustainable extension service. 相似文献
3.
4.
Workineh S Bayleyegn M Mekonnen H Potgieter LN 《Tropical animal health and production》2002,34(1):19-25
The study was undertaken to determine the aetiology and prevalence of mastitis in hand-milked cows (n = 186) in two major Ethiopian dairies. The California Mastitis Test and culturing for bacteria revealed that 21.5% of the cows were clinically infected and 38.2% had subclinical mastitis. Most mastitis pathogens isolated from milk samples testing positive by the California Mastitis Test were Gram-positive cocci. Staphylococci constituted 57% of the isolates, of which the predominant cause of bovine mastitis was Staphylococcus aureus (40.5%). Other mastitis pathogens isolated include streptococci (16.5%), coliforms (9%) and corynebacteria (5%). Retrospective analysis of farm records indicated that mastitis was the second most important cause of culling and accounted for 27% of the cows removed from these two dairies. 相似文献
5.
Mekonnen S 《The Onderstepoort journal of veterinary research》2000,67(4):235-237
The efficacy of a flumethrin 1% pour-on (Bayticol, Bayer AH) was evaluated against natural infestations of ticks on cattle on a dairy farm in Ethiopia during 1997/98. The cattle, (n = 92), which were Friesian/ Zebu crosses, were heavily infested with Boophilus decoloratus. Dry cows (n = 8) were randomly selected and allocated either into a treatment or a control group. Flumethrin 1 % pour-on was applied to the treatment group according to the manufacturer's recommendation, i.e. along the dorsal mid-line from the head to the base of the tail. Ticks were counted and identified in situ on treated and control animals. When the total tick counts of the treated group were similar to those on the control, the trial was discontinued. Excellent results were achieved with flumethrin against heavy tick infestations. There was a rapid kill after 24 h post-treatment, and from day 4 onwards 100% control was achieved and maintained for a further 29 days. The results obtained indicate that there was a significant difference between the mean tick counts of the control group compared with those of the treatment group (P < 0,05). The evidence presented here suggests that the flumethrin 1 % pour-on may be applied at 45 day intervals and should provide effective protection against the economically important ticks if it is used at the recommended dosage rate and applied correctly. 相似文献
6.
Tree planting for poverty reduction in less-favoured areas of the Ethiopian highlands 总被引:1,自引:0,他引:1
This paper assesses the potential impact of planting of eucalypt trees as a strategy to reduce poverty in a less-favoured
area of the highlands of Ethiopia. Results from simulations with a bio-economic model for a less-favoured case study area
in the highlands are combined with survey data at community, household and plot level to assess how general the results of
the bio-economic model are. Application of the bio-economic model shows clearly that land degradation, population growth,
stagnant technology and drought threaten food security. Household welfare and land quality are deteriorating rapidly in the
area and interventions are urgently needed to avoid human disaster. Planting of eucalypts on land unsuitable for crop production
may substantially increase household incomes if market outlets for trees can be found. Tree planting will not have severe
negative effects on food production or land conservation. A policy combining promotion of tree planting and conservation of
cropland may achieve win-win benefits in terms of increased household incomes as well as more sustainable land-use. Analysis
of survey data from the Amhara Region of Ethiopia reveals that there is a large area of land that is unsuitable for crop production
located close to all-weather roads in the less-favoured areas of the region. Few trees have been planted on this type of land
up to now. The past policy seems to have discouraged tree planting except on homestead plots that are more suitable for food
crops.
This paper reports part of the IFPRI/ILRI project ‘Policies for Sustainable Land Management in the East African Highlands’.
These two agencies have provided funds and logistical support for the work. The Norwegian Ministry of Foreign Affairs has
provided funds for this research in the Amhara Region in Ethiopia. The authors also draw on earlier work funded by Research
Council of Norway. Any correspondence should be directed to the first author. 相似文献
7.
8.
The study was conducted to estimate the proportion of reproductive disorders and to determine factors affecting reproductive performance of crossbred dairy cows under four different production systems in the central highlands of Ethiopia. The principal postpartum reproductive disorders were retained fetal membranes (14.7%) and uterine infection (15.5%). Anoestrus was the major postpartum reproductive problem in the mixed crop–livestock production system (38.6%) and was significantly associated with this production system. Apart from anoestrus, the occurrence of reproductive disorders was not significantly associated with a production system. Most of the reproductive disorders occurred as a complex rather than as a single abnormality. Two or more abnormal conditions were seen in 11.4% of the cases. Each reproductive trait measured was affected adversely by reproductive disorders. Cows with reproductive disorders in each production system, lactation group and suckling and non-suckling group had longer intervals from calving to first service and to conception (p < 0.001) and required more services per conception (p < 0.001). Pregnancy rate and conception to first service were 84.7% and 51.7%, respectively, for cows without reproductive health problems; and 64.2% and 15.1%, respectively, for cows with reproductive disorders (p < 0.001). Overall, intervals from calving to first service were shorter (p < 0.05) than in younger cows. Intervals from calving to first service and to conception were longer in suckling than in non-suckling cows (p > 0.05). Cows with a good body condition score (>3.5) at calving had shorter calving to first service and conception intervals than cows in poor condition (p < 0.001). The results showed that reproductive abnormalities, coupled with poor body condition, are important factors that contributed to reproductive inefficiency. An appropriate reproductive health management, a reliable artificial insemination service and supplementary feeding could be the management options to reduce or alleviate some of the problems. 相似文献
9.
Reduced Milk Production in Udder Quarters with Subclinical Mastitis and Associated Economic Losses in Crossbred Dairy Cows in Ethiopia 总被引:2,自引:1,他引:1
Mungube EO Tenhagen BA Regassa F Kyule MN Shiferaw Y Kassa T Baumann MP 《Tropical animal health and production》2005,37(6):503-512
The objective of the study was to estimate the losses associated with subclinical mastitis (SCM) in crossbred dairy cows in
the Central Highlands of Ethiopia. A split udder investigation was performed with 30 cows to determine production losses associated
with SCM. Each quarter of the study cows was examined using the California Mastitis Test (CMT) and quarter milk production
was measured over a period of 8 days. Production losses were determined for different CMT scores by comparing production of
quarters with CMT score 0 to quarters with CMT scores trace, 1, 2 and 3, respectively. Using data from a recently published
study, economic losses were determined for different farm sizes and production subsystems by multiplying the prevalence of
the respective CMT scores with the production losses associated with these CMT scores. Mean quarter milk production was 0.82
+ 0.40 kg per milking in the split udder trial. Milk production was reduced by 1.2%, 6.3%, and 33% in quarters with CMT scores
1+, 2+, and 3+, respectively. Using data from the published study, a quarter with SCM lost an average of 17.2% of its milk
production. Production losses associated with SCM were estimated at 5.6% for the Addis Ababa Milk Shed. Stratified losses
were highest (9.3%) in urban dairy farms (UDF) and small-scale farms (6.3%). The estimates of the financial losses ranged
from US$29.1 in dairy herds in secondary towns (DHIST) to US$66.6 in UDF. A total loss of US$38 was estimated for each cow
per lactation. Reducing mastitis in UDF (highest prevalence) to the level of DHIST (lowest prevalence) could reduce the loss
by US$35. As this does not include costs associated with treatment or culling of diseased cows, this figure probably underestimates
the possible benefits of control measures. 相似文献
10.
Shiferaw Jenbreie Gelagay Ayelet Esayas Gelaye Fekadu Kebede Stacey E. Lynch Haileleul Negussie 《Tropical animal health and production》2012,45(1):75-79
The study was conducted in eight districts of Ethiopia with the objectives of determining the seroprevalence and associated risk factors of infectious bursal disease (IBD). From the total of 2,597 chicken serum samples examined using ELISA, 83.1 % were found positive. The highest seroprevalence was found at Mekele (90.3 %) while the lowest was recorded at Gondar district (69.8 %). These differences among the study areas were statistically significant (p?<?0.05). Highest seroprevalence was found in crossbreed of chicken (91.4 %) while the lowest was recorded in indigenous breed of chicken (81.4 %). This difference was statistically significant (p?<?0.05) among the three breeds of chickens, but sex was not statistically significant (p?>?0.05). The seroprevalence of the disease was found high in young (≤8 weeks) age group (86.6 %) while the lowest prevalence was recorded in adults (>8 weeks) (72 %). This is also statistically significant (p?<?0.05) between young and adult age groups. The prevalence of IBD in different production system indicated that higher seroprevalence was recorded in intensive production system (85.9 %) while the lowest was recorded in extensive production system (81.6 %). This difference is also statistically significant (p?<?0.05). 相似文献