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Gebru Gebreslassie Tekle Desta Belay Shumuye 《Tropical animal health and production》2018,50(3):659-664
The objective of the study was to evaluate the effect of supplementation of indigenous browse tree pods on nutrient intake, digestibility, weight gain, and carcass parameters of local Abergelle rams fed grass hay as a basal diet. This experiment was conducted at the Abergelle Agricultural Research Center farm in Tigray region, northern Ethiopia. Experimental rams were grouped according to their initial body weight (17.4?±?0.95 kg) in a randomized complete block design into three treatments and six replications. Treatments consisted of feeding grass hay free of choice supplemented with pods of either Acacia tortilis (T1), Faidherbia albida (T2), or Dichrostachys cinerea (T3) fed at the rate of 10 g kg?1 body weight daily. The crude protein (CP) contents of the supplemental feeds in T1, T2, and T3 were 167, 156, and 135 g kg?1 dry matter (DM), respectively. The CP intake was significantly higher (P?<?0.05) in T1 and T2 than that in T3. No statistical difference (P?>?0.05) was observed in the digestibilities of DM and CP. Final body weight, average daily gain, slaughter weight (SW), hot carcass weight, and ribeye area were not significantly different (P?>?0.05) among the treatments. However, dressing percentage based on SW in T1 and T2 was significantly higher (P?<?0.05) than that in T3. Therefore, from this research, it can be concluded that though the weight gains and carcass weights of experimental rams were not as such remarkable among the treatments, efficient utilization of locally available and cheap browse tree pods as alternative protein supplements to Abergelle sheep during the dry season could be important to small holder farmers.
相似文献2.
The feasibility of hyperspectral imaging (HSI) to detect deoxynivalenol (DON) content and Fusarium damage in single oat kernels was investigated. Hyperspectral images of oat kernels from a Fusarium‐inoculated nursery were used after visual classification as asymptomatic, mildly damaged, and severely damaged. Uninoculated kernels were included as controls. The average spectrum from each kernel was paired with the reference DON value for the same kernel, and a calibration model was fitted by partial least squares regression (PLSR). To correct for the skewed distribution of DON values and avoid nonlinearities in the model, the DON values were transformed as DON* = [log(DON)]3. The model was optimized by cross‐validation, and its prediction performance was validated by predicting DON* values for a separate set of validation kernels. The PLSR model and linear discriminant analysis classification were further used on single‐pixel spectra to investigate the spatial distribution of infection in the kernels. There were clear differences between the kernel classes. The first component separated the uninoculated and asymptomatic from the severely damaged kernels. Infected kernels showed higher intensities at 1,925, 2,070, and 2,140 nm, whereas noninfected kernels were dominated by signals at 1,400, 1,626, and 1,850 nm. The DON* values of the validation kernels were estimated by using their average spectra, and the correlation (R) between predicted and measured DON* was 0.8. Our results show that HSI has great potential in detecting Fusarium damage and predicting DON in oats, but it needs more work to develop a model for routine application. 相似文献
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Response of four indigenous cattle breeds to natural tsetse and trypanosomosis challenge in the Ghibe valley of Ethiopia 总被引：1，自引：0，他引：1
Lemecha H Mulatu W Hussein I Rege E Tekle T Abdicho S Ayalew W 《Veterinary parasitology》2006,141(1-2):165-176
A comparative study on the response of four indigenous cattle breeds of Ethiopia, namely Abigar, Horro, Sheko and Gurage, to natural challenge of trypanosomosis in the Tolley-Gullele area of the Ghibe valley has been undertaken from August 2000 until August 2004. Fifty female yearlings each of Horro, Sheko and Abigar and 31 of the Gurage were purchased from their natural habitats and introduced in to medium to high tsetse-trypanosomosis challenge area of the Ghibe valley. While the natural habitats of first three breeds are naturally infested with tsetse flies and trypanosomosis, that of the Gurage is known to be very minimal, if any, and hence the Gurage breed was used in this study as the known susceptible breed. During the study animal health, production performance and tsetse fly situation were monitored monthly. The Sheko breed has manifested very significantly (p<0.001) high overall average packed cell volume (PCV) values (25%) compared to that of Abigar (24%), Horro (23%) and Gurage (22%). It also had the lowest mean trypanosome prevalence rate of 9% against 23% of Horro, 26% of Abigar and 27% of Gurage, and the least number of Berenil treatments (1.36) compared to Abigar (4.0), Horro (4.6) and Gurage (6.7). While the Abigar manifested high sensitivity and frequent death to PCV depression, the Horro showed strong resilience to PCV depression and better response to Berenil treatment assistance. At this stage the Sheko breed was also found to be equal to the other breeds in its reproductive performance. These results need to be substantiated with further in-depth investigation including immune response, animal behavior and environmental influences. 相似文献
4.
Stone RG Pedersen BM Harvey CC Canu P Cornilleau-Wehrlin N Desch MD de Villedary C Fainberg J Farrell WM Goetz K Hess RA Hoang S Kaiser ML Kellogg PJ Lecacheux A Lin N Macdowall RJ Manning R Meetre CA Meyer-Vernet N Moncuquet M Osherovich V Reiner MJ Tekle A Thiessen J Zarka P 《Science (New York, N.Y.)》1992,257(5076):1524-1531
The Unified Radio and Plasma Wave (URAP) experiment has produced new observations of the Jupiter environment, owing to the unique capabilities of the instrument and the traversal of high Jovian latitudes. Broad-band continuum radio emission from Jupiter and in situ plasma waves have proved valuable in delineating the magnetospheric boundaries. Simultaneous measurements of electric and magnetic wave fields have yielded new evidence of whistler-mode radiation within the magnetosphere. Observations of aurorallike hiss provided evidence of a Jovian cusp. The source direction and polarization capabilities of URAP have demonstrated that the outer region of the lo plasma torus supported at least five separate radio sources that reoccurred during successive rotations with a measurable corotation lag. Thermal noise measurements of the lo torus densities yielded values in the densest portion that are similar to models suggested on the basis of Voyager observations of 13 years ago. The URAP measurements also suggest complex beaming and polarization characteristics of Jovian radio components. In addition, a new class of kilometer-wavelength striated Jovian bursts has been observed. 相似文献
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Selamawit Tekle Helge Skinnes ?smund Bj?rnstad 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(1):147-158
Mycotoxin contamination and reduced germination capacity (GC) of oats affected by Fusarium head blight (FHB) have become serious concerns in Norway. Spawn- and spray-inoculated field trials were conducted from 2007 to 2010 to screen for resistant genotypes and to study the relationship between GC and deoxynivalenol (DON) contamination. Correlation coefficients between GC and DON level varied from ?0.412 to ?0.711 (P?<?0.001). The strongest and the weakest correlations were recorded for the spray- and spawn-inoculated experiments of 2009, respectively. High DON levels were associated with low GCs but low DON levels did not guarantee higher GCs. DON did not inhibit initiation of germination, but did retard seedling growth in a germination assay conducted on DON-amended water agar. Most of the seedlings grown on the modified WA containing even as little as 2?ppm DON had abnormal morphology and would not be considered as ??germinated?? in official tests. A greenhouse experiment studying the effect of time of inoculation on GC, DON level, and seed infection (SI) showed a rapid reduction in DON levels resulting from later inoculations. Increments in GC were observed although they were not as strong as the decrements in DON level. Seed infection remained consistently high (> 60?%) for all inoculations. Seed dressing and dehulling individually were not effective in improving GC, but when combined increased GC to the percentage of kernels having viable germ. We hypothesize that in addition to the level of DON, SI influences the GC of Fusarium-damaged oats, especially in wet years that may facilitate late-initiated infections. 相似文献
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Stein J Ayalew W Rege E Mulatu W Lemecha H Tadesse Y Tekle T Philipsson J 《Veterinary parasitology》2011,178(1-2):40-47
We conducted a two-part study in the native home areas of four cattle breeds, Abigar, Gurage, Horro and Sheko, in south-western Ethiopia. The first part of the study investigated livestock keeper knowledge about trypanosomosis and trypanotolerance. For each breed 60 livestock keepers were interviewed, resulting in a total of 240 interviews. The second part of the study focused on biological evidence for trypanotolerance. Blood samples of about 100 head of cattle per breed were collected during peak trypanosomosis challenge period and analyzed for packed cell volume (PCV) and parasitaemia. In addition individual body measurements of the sampled animals were taken and the keepers provided some information regarding their animals. Livestock keeper interviews revealed that trypanosomosis was considered a major problem in all areas (95-100%). Almost all Abigar livestock keepers knew how trypanosomosis is transmitted, whereas only 34-52% of the keepers of the other breeds had that knowledge. Most Sheko keepers (75%) knew of trypanotolerance and claimed to have trypanotolerant animals in their own herds. Among the other three breeds the knowledge of trypanotolerance was much less (8-18%). A majority of the keepers were interested in purchasing trypanotolerant animals. PCV was highest among Horro (26.2) and Sheko (25.1) cattle whereas Abigar had the lowest PCV (20.0). Sheko were least infected by trypanosomes (6%) and had the lowest number of trypanocidal treatments per year (1 treatment/animal and year). Abigar cattle were most infected (23%) followed by Gurage (20%) and Horro (17%). Gurage had by far the highest number of treatments per animal and year (24). There were large differences between the number of cattle perceived by the keepers to be infected, and the number detected from blood sampled, among Abigar, Gurage and Horro. Sheko livestock keepers were better at correctly diagnosing trypanosomosis in their animals. It is concluded that Sheko cattle have higher trypanotolerance attributes of the breeds investigated and a better use of this breed could improve cattle health and household welfare in tsetse-infested areas. 相似文献
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Åsmund Bjørnstad Selamawit Tekle Magnus Göransson 《Genetic Resources and Crop Evolution》2013,60(7):1959-1965
The International Treaty on Plant Genetic Resources for Food and Agriculture entered into force in 2004 and is an important instrument by which plant breeders can access crop genetic diversity on the basis of multilateral “facilitated access”. To test how well access works, we sent seed requests to 121 countries that are Contracting Parties to the Treaty. Seeds were received from 44 countries, 54 countries did not respond, while for 23 countries contacts stopped for various reasons: loss of communication, the accessions we requested did not exist or were not in the multilateral system, or conditions or standard material transfer agreements were different from those specified in the Treaty. It is concluded that after nearly 10 years, “facilitated access” is not straightforward. 相似文献
8.
Genetic variation and associations involving Fusarium head blight and deoxynivalenol accumulation in cultivated oat (Avena sativa L.) 
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下载免费PDF全文 Åsmund Bjørnstad Xinyao He Selamawit Tekle Kathy Klos Yung‐Fen Huang Nicholas A. Tinker Yanhong Dong Helge Skinnes 《Plant Breeding》2017,136(5):620-636
Resistance in oats (Avena sativa L.) to Fusarium graminearum was phenotyped in 424 spring oat lines from North America and Scandinavia and genotyped with 2974 SNP markers. Fusarium head blight (FHB), deoxynivalenol (DON) content, days to flowering (DTF) and days to yellow maturity (DTM) were scored in field trials in 2011–12. Trials with phenotypic ranges from 1 to 30 ppm, and sufficient accuracy were obtained by an augmented design and spawn inoculation. Discriminant analysis–PCA identified the different gene pools, with overlaps corresponding to known pedigrees and germplasm exchanges. Structure was negligible and GWAS (genomewide association study) was done using mixed linear models in TASSEL or partial least‐squares regression (PLSR). PLSR allows simultaneous analyses of several phenotypes (environments and/or traits) and is a promising tool for GWAS in plants and should be tested in species with sequenced genomes. FHB was associated with phenology QTLs, due to very susceptible early lines from the Midwest. Lines with consistently low DON (and early heading) were identified. Six QTLs for DON were not associated with earliness, including three QTLs reported previously. 相似文献
9.
Selamawit?TekleEmail author Ruth?Dill-Macky Helge?Skinnes Anne?Marte?Tronsmo ?smund?Bj?rnstad 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(3):431-442
Fusarium head blight in small grain cereals has emerged as a major problem in the Nordic countries. However, the impact of
this disease in oats has been less investigated than in other cereals. For this reason we have studied the infection process
(the optimal time of infection and infection pathways) of Fusarium graminearum in oats and its subsequent effects on kernel infection, deoxynivalenol (DON) content and germination capacity. In a field
experiment the oat cultivar Morton was spray-inoculated at different developmental stages, and the highest kernel infection
and DON content and lowest germination percentage were observed when inoculation took place at anthesis. Field grown oats
affected by a natural Fusarium head blight epidemic and spray-inoculated field and greenhouse oats were used to study the
infection pathway. Results showed that the fungus entered primarily through the floret apex into the floret cavity, where
it could infect via the internal surfaces of the palea, lemma and caryopsis. Both visual symptoms and fungal infections started at the apical
portions of the florets and progressed to the basal portions. Hyphae of F. graminearum grew more profusely on the anthers than on other floret parts during initial stages of infection. Disease development within
the oat panicle was slow and is primarily by physical contact between adjoining florets, indicating that the long pedicels
give Type II resistance in oats. 相似文献
10.
Selamawit Tekle smund Bj&#x;rnstad Helge Skinnes Yanhong Dong Vegard H. Segtnan 《Cereal Chemistry》2013,90(3):181-185
The potential of VIS‐NIR spectroscopy as a rapid screening method for resistance of Fusarium‐inoculated oats to replace the costly chemical measurements of deoxynivalenol (DON) was investigated. Partial least squares (PLS) regression was conducted on second‐derivative spectra (400–2,350 nm) of 166 DON‐contaminated samples (0.05–28.1 ppm, mean = 13.06 ppm) with separate calibration and test set samples. The calibration set had 111 samples, and the test set had 55 samples. The best model developed had three PLS components and a root mean square error of prediction (RMSEP) of 3.16 ppm. The residual predictive deviation (RPD) value of the prediction model was 2.63, an acceptable value for the purpose of rough screening. Visual inspection and the VIS spectra of the samples revealed that high‐DON samples tended to be darker in color and coarser in texture compared with low‐DON samples. The second‐derivative spectra showed that low‐DON samples tended to have more water and fat content than high‐DON samples. With an RMSEP value of 3.16 and RPD of value of 2.63, it seems possible to use VIS‐NIR spectroscopy to semiquantitatively estimate DON content of oats and discard the worst genotypes during the early stages of screening. 相似文献
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