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31.
Thirty yearling male intact Arsi-Bale sheep with initial body weight (BW) of 15.5 ± 0.21 kg (mean ± SD) were used in 90 days
feeding trial, 10 days digestibility trial followed by evaluation of carcass parameters at Bokoji, Ethiopia. The objectives
were to evaluate effects of supplementation with linseed (Linum usitatissimum) cake (LSC), wheat bran (WB), and their mixtures at 2:1 and 1:2, respectively on feed intake, digestibility, daily BW gain,
and carcass parameters. The five treatments included ad libitum feeding of natural pasture hay (control) and with daily supplementation
of 300 g dry matter (DM) sole LSC, 2LSC:1WB mix, 1LSC:2WB mix, and sole WB. Six sheep were randomly assigned to each treatment
using randomized complete-block design. Four sheep in each treatment were randomly selected and used for determination of
digestibility and carcass characteristics using a completely randomized design. The intake of hay DM was higher (P < 0.001) for the non-supplemented sheep compared with the supplemented ones, but the contrary was true for total DM intake.
Sheep in the control treatment lost BW (−1.5 g/day), while the supplemented ones gained 69.0–104.1 g BW/head/day. Digestibility
of CP was higher (P < 0.001) for supplemented sheep as a result of higher (P < 0.001) CP intake. Slaughter weight, empty BW, and hot carcass weight were lower (P < 0.001) for sheep in the control treatment compared with the rest. Sheep supplemented with LSC and its mixtures with WB
had better (P < 0.001) performance in daily BW gain than sole WB supplemented ones indicating the advantages of using supplements as mixed
rations. Moreover, supplementation proved to be profitable, whereas feeding hay alone led to economic loss. 相似文献
32.
Abebe Menkir Bussie Maziya-Dixon Wende Mengesha Torbert Rocheford Emmanuel Oladeji Alamu 《Euphytica》2017,213(5):105
Maize has been targeted as one of the major crops for provitamin enrichment and delivery because it is an inexpensive and easily available source of food for millions of people in sub-Saharan Africa. Although tropical-adapted yellow maize contains provitamin-A carotenoids that can be converted into vitamin A in the human body, they represent less than 25% of the total carotenoids in most widely grown and consumed maize cultivars in Africa. Novel genes conditioning high concentration of β-carotene and other carotenoids were then continually introduced from the temperate zone and tropics to boost provitamin A in tropical-adapted maize. Several promising inbred lines developed from backcrosses involving diverse exotic donor lines displayed provitamin A concentrations that match or surpass the current breeding target of 15 μg g?1. Some of these lines attained high provitamin A content by accumulating mainly high β-carotene while others contained high provitamin A by promoting accumulation of high levels of both carotenes and xanthophylls. Several inbred lines with intermediate to high levels of provitamin A have already been used to develop hybrids and synthetics without compromising grain yield and other adaptive traits that are required to profitably cultivate maize by farmers in West and Central Africa. 相似文献
33.
Ten Boran (Bos indicus) cattle were used to study the stress responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis during trypanosome infection. Five cattle were infected with Trypanosoma congolense IL 1180 by tsetse challenge and five cattle served as controls. All infected animals developed acute trypanosomiasis. Insulin-induced hypoglycaemia (50 per cent of pre-insulin glucose concentration) was used as a stress factor. Acute hypoglycaemia was observed in three infected and three control animals after insulin challenge. Two animals from each group either did not respond or responded slowly. Hypoglycaemia in infected animals completely failed to induce an HPA axis response, while in control animals an HPA axis response was indicated by a significant increase in plasma adrenocorticotrophic hormone (ACTH) and cortisol concentrations (P less than 0.01). The results show that trypanosomiasis in Boran cattle can cause a decrease in the stress responsiveness of the HPA axis as indicated by a blunted ACTH/cortisol response to insulin-induced hypoglycaemia. 相似文献
34.
35.
Two experiments were conducted in the Rift Valley, Ethiopia (8°N and 39°E) to determine associations between eight plant traits
and seed yield, and to obtain estimates of narrow sense heritability for the traits. Experiment I evaluated seven dry edible
bean cultivars/lines at two locations to simulate different soil moisture stress, including, Debre Zeit(non-stress) and Dera
(moderate-stress). Experiment II evaluated 25 cultivars/lines in three environments including, Melkassa early planted (non-stress),
Melkassa late planted (high-stress), and Dera (moderate-stress). A randomized-complete-block design with three replicates
was used in both experiments. Plant traits evaluated were seed yield, pods plant-1, seeds pod-1, 100 seed weight, root dry weight, hypocotyl diameter, plant biomass, plant height and days to flowering. Plant traits that
were significantly associated with seed yield were included in a stepwise-regression model to determine which trait or combination
of traits provided the best model to estimate seed yield in each environment. An analysis of variance was conducted to test
main effects and interactions between plant traits and environments. Significant variation among lines occurred for seed yield
and all plant traits in both experiments. Strong positive correlations were observed between plant biomass and seed yield
in all environments. Seed yield and pods plant-1 were also highly associated in four of the five environments. Stepwise regression models indicated that the combination of
pods plant-1 and plant biomass consistently contributed to seed yield prediction, while other traits did not. Because both plant biomass
and pods plant-1 had moderate to high narrow sense heritability estimates and low GE interactions, they should be useful as indirect selection
criteria to improve and stabilize seed yield in a breeding program.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
36.
37.
An analysis of the variability of genes encoding six isozyme systems (15 loci) and two storage proteins (2 loci) in landrace barley from Ethiopia is reported. The materials consisted of populations collected from sites as low as 1650 and as high as 3750 meters, covering a wide range of agro-ecological conditions and geographical areas. Of the 17 loci 7 were polymorphic and 10 monomorphic when the 95% criterion of polymorphism was applied. Despite the disproportionate monomorphic loci, polymorphism was detected in all populations when this criterion is used. The populations were found to possess fairly low mean number of alleles per locus (A = 1.5), low mean value of expected heterozygosity (H = 0.134) and a fairly high mean percentage of polymorphic loci (P = 35.3%). The mean FST= 0.474 for the populations is typical of inbreeding species. The result indicated that allelic richness is concentrated in altitude class 3 (2500–3000 m) followed by altitude class 1 (<2000 m). Altitude class 2 (2000–2500) holds an intermediate place though it is the highest in terms of expected heterozygosity (H = 0.245). Higher genetic diversity is concentrated in some geographical regions such as Shewa, Arsi, Bale compared to others (Welo, Gamu Gofa, Gojam). Genetic differentiation among the agro-ecological zones was more profound than both among the altitudes and among regions. Correlation analysis between phenotypic diversity (Shannon-Weaver diversity index) and expected heterozygosity (H) for isozyme/hordein loci revealed non significant associations except with respect to agro-ecological zones. In general, it was detected that sites in highland areas in central and northern regions may be more desirable for in situ conservation than sites in peripheral regions in terms of isozyme/hordein diversity and current rate of varietal replacement. 相似文献
38.
Temesgen Wakweya Abebe Nigussie Gebeyanesh Worku Armaye Biresaw Abebayheu Aticho Obsu Hirko Gebermedihin Ambaw Melkamu Mamuye Bayu Dume Milkiyas Ahmed 《Soil Use and Management》2022,38(1):703-713
Although the addition of biochar has been shown to reduce the phosphorus (P) adsorption capacity of soil, quantitative evidence of this has mainly been provided by incubation experiments and it is therefore essential to conduct long-term field trials to draw general conclusions. It is largely unknown whether bone char has a greater effect than lignocellulosic biochar on P adsorption–desorption processes and crop yield. The aim of this study was to determine the long-term (8 years) effect of bone char and biochar on P adsorption–desorption and crop yield in low-input acidic soils. The results showed that bone char decreased the maximum P adsorption capacity (Qm) by 10% and increased the desorption capacity (Ds) by 150% compared with the control (i.e. without a soil amendment). The desorption ratio was highest for the bone char treatment (10.3%) and three times more than the control. Plant-available P was seven times greater under bone char than the control. There was no variation in adsorption–desorption characteristics, desorption ratio and plant-P available content between bone char and lignocellulosic biochar treatments. The average yield increment following the application of bone char and biochar was 1.7 and 1.4 Mg ha−1 for maize and 1.8 and 1.9 Mg ha−1 for soya bean, respectively. Despite the low application rate (4 t ha−1 year−1), these findings demonstrated that the long-term application of bone char and biochar-based amendments enhanced P availability in low-input cropping systems, mainly by altering the P adsorption and desorption capacity of soils. 相似文献
39.
Gastrointestinal nematode infections in small ruminants under the traditional husbandry system during the dry season in southern Ethiopia 总被引:1,自引:0,他引:1
Rahmeto Abebe Mebrahtu Gebreyohannes Solomon Mekuria Fufa Abunna Alemayehu Regassa 《Tropical animal health and production》2010,42(6):1111-1117
A cross-sectional study was conducted from November 2008 to February 2009 to investigate the prevalence and intensity of infection
and risk factors of gastrointestinal (GI) nematodes in small ruminants kept under the traditional husbandry system in two
districts in southern Ethiopia. Faecal samples collected from a total of 510 small ruminants (284 sheep and 226 goats) and
analysed by a modified McMaster technique revealed that 222 animals (43.5%) were found to be infected with one or more GI
nematodes. Five identical genera of nematodes were found in both sheep and goats, which in order of predominance were Haemonchus (56.3%), Trichostrongylus (39.6%), Oesophagostomum (22.9%), Trichuris (21.6%) and Bunostomum (10.4%). No significant (p > 0.05) differences were observed between sheep and goats proportions except for Trichuris (p < 0.05). In both sheep and goats, most of the animals were heavily infected showing faecal egg counts (FECs) above 1,200 epg.
Sheep had a significantly (p < 0.05) higher mean FEC than goats. In sheep and goats, both the prevalence of GI nematodes and mean FEC were significantly
(p < 0.001) associated with body condition score and faecal consistency but not with district, sex and age (p > 0.05 for each factor). In conclusion, the observation of a strong association of GI nematodes with poor body condition
coupled with heavy intensity of infection in the majority of infected animals and an abundance of nematode genera of widespread
economic and pathological significance warrants the institution of appropriate control measures that should necessarily include
improvement of the nutritional status of the animals. 相似文献
40.
Legesse Getahun Siegmund-Schultze Marianna Abebe Girma Valle Zárate Anne 《Tropical animal health and production》2010,42(7):1531-1539
This study evaluates the household income contribution and the profitability of traditional small ruminant enterprises in
two mixed-farming systems of southern Ethiopia (viz. Adilo and Kofele). Small ruminant production is an integral part of mixed systems in the Ethiopian highlands. The assessment
of the current economic performance of small ruminants indicates production-related opportunities and constraints and provides
baseline data against which the success of future interventions can be measured. Detailed information on economic parameters
was gathered through a 1-year period of flock and household monitoring (155 households) between September 2005 and August
2006. Structured surveys were conducted with the participating households to elicit information on income-expense details
of small ruminant and other agricultural enterprises. Small ruminants contributed considerably to cash income and to a limited
extent to human nutrition especially when other sources were in short supply. The annual profit per animal ranged from 20
to 37 Ethiopian Birr. The return to capital was 17% in Kofele and 29% in Adilo, with both values vastly exceeding the national
interest rate. The sale of small ruminants contributed to 39% and 23% of total farm cash income among small ruminant keepers
in Adilo and Kofele, respectively. Sale prices are highest before holidays. Researches should target at how to use available
feed resources in a timely and cost-effective fashion to make use of the seasonal market opportunities. 相似文献