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Open pollinated maize varieties are one of the best options for farmers who cannot afford the cost of hybrids, cultivating maize in low potential environments and cannot pay for inputs such as fertilizers and pesticides. The experiment was conducted to use farmers’ input and feedback on selection of well-adapted, high-yielding, and disease-tolerant maize varieties. Treatments were arranged incompletely randomized block design with three replications. Gibe-1 was better preferred open pollinated maize variety by famers due its cob length, disease tolerance, good husk cover and yield. Gibe-1 provided the highest grain yield in South Achefer (8.8 t ha-1) and the best performing genotype across environments with grain yield of 7.8 t ha-1. Gibe-1 also had a good reaction to common leaf rust and tercicum leaf blight. GGE biplot analysis classified testing environments in to four mega environments and showed high influence of the environment to grain yield with the contribution of variation 59.59% by the environment, 7.25% by the genotype, and 18.38% by interaction. Gibe-1 was identified as the most ideal open pollinated maize variety which produced the highest mean grain yield and was the most stable. Therefore, Gibe-1 is recommended as a potential open pollinated maize variety for Jabitehinan, South Achefer, and similar agro ecologies.  相似文献   
2.
The objective of this study was to determine the effect of supplementing increasing levels of dried tagasaste (Chamaecytisus palmensis) leaf on the nutrition and performance of sheep fed a basal diet of barley straw. The study had four treatments, which involved supplementation of dried tagasaste leaf at 100, 200, 300, and 400 g/day. Twenty-four yearling Menz sheep (weight 17 ± 0.83 kg) were assigned to one of the four treatments in a randomized complete block design. The experiment comprised a feeding trial lasting for 90 days, a digestibility trial, and carcass evaluation using all animals. Samples of the feed consumed, refused, and feces were analyzed for nutrients. Intake and digestibility of dry matter (DM) and nutrients increased linearly (P < 0.001) as tagasaste supplementation increased from 100 to 400 g/day. Similarly, average daily body weight gain increased linearly (P < 0.001) from 20 to 73 g/day, feed conversion efficiency from 0.04 to 0.10, and dressing percentage from 40 to 48%, as the supplementation increased from 100 to 400 g/day. Proportion of tagasaste leaf in the diet increased from 20 to 50%, while the ratio of neutral detergent fiber (NDF) to crude protein (CP) decreased from 7.9 to 5.3, as the level of supplementation increased. It was thus concluded that supplementation of dried tagasaste leaf up to 50% of the diet DM, resulting in a NDF:CP ratio of 5.3, produces no deleterious effects on the performance of sheep, and inclusion to this level can be applied for superior growth performance and carcass yield in sheep fed crop residue-based diets.  相似文献   
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4.
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   
5.

Background

Ethiopia, particularly in the Northwest region, is affected by both tsetse and non-tsetse fly transmitted trypanosomosis, with significant impact on livestock productivity. The aim of this study was to determine and compare clinical findings and haematological values between experimental infections induced by Trypanosoma vivax isolates from areas of either transmission mode. Sixteen young (aged between 6 and 12 months) Zebu cattle (Bos indicus), purchased from a trypanosome-free area and confirmed to be trypanosome-negative, were randomly assigned into four groups of four animals. Groups 1, 2 and 3 were infected with an isolate from a tsetse infested or one of two isolates from a non-tsetse infested area, and group 4 was a non-infected control. All animals in the infected groups were inoculated intravenously with 2 × 106 trypanosomes from donor animals. The experimental animals were monitored for eight consecutive weeks post infection for clinical signs, parasitaemia and haematological changes in packed cell volume (PCV), haemoglobin concentration (Hgb), total red blood cell (RBC) and white blood cell (WBC) counts, differential WBC count and blood indices (mean corpuscular volume [MCV], mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration).

Results

Infection was characterized by reduced feed intake, weakness, pyrexia, parasitaemia, rough hair coat, enlarged prescapular lymph nodes, lacrimation, weight loss, pallor mucus membrane and dehydration. Body weight loss in all infected groups was significantly higher than in the non-infected control. Similarly, body weight loss was higher (P < 0.001) in animals infected with the tsetse infested isolate than with the non-tsetse infested isolates. The mean PCV, Hgb, total RBC and WBC counts were lower (P < 0.001), and mean MCV was higher (P = 0.01) in all infected groups than in non-infected control animals at different time points during the study period. Except for minor variations in haematological values, the overall changes were similar in all infected groups.

Conclusion

Clinical signs and significant reduction in haematological values in the infected groups indicated the pathogenicity of the T. vivax parasites. Pathogenicity of T. vivax from the non-tsetse infested area can be considered as nearly as important as that of its counterpart derived from the tsetse infested area.  相似文献   
6.
The ratio of monounsaturated oleic fatty acid to polyunsaturated linoleic fatty acid (O/L) and the associated agronomic traits were profiled for local peanut (Arachis hypogaea L.) cultivars and accessions in Botswana. The research was tested on 16 entries planted in four localities across the country. The average total oil yield of the genotypes studied was about 42.1% and there was no significant difference in total oil yield (P < 0.05) across the four research sites and among all entries (accessions). The average mean O/L ratio for all entries was about 1.47. The highest was that of the locally improved variety, Peolwane (2.58), which was significantly different (P < 0.05) from all other accessions, and the lowest is that of the local accession GO 63 (1.23). This study also profiled the agronomic yield traits to identify genotypes that have both high oil quality and high yielding potential. No correlation was detected between pod yield and O/L ratio among the tested genotypes. The station with little rainfall but adequate repartition showed a very high O/L ratio for some genotypes, and future work is recommended to test this interesting observation on the correlation between moisture stress and oil quality.  相似文献   
7.
The aim of this study was to evaluate the nutritional and feeding value of peanut hay (Arachis hypogaea L.) produced under tropical environment as an alternate forage resource for sheep. Peanut hay was appreciably high in crude protein [CP; 105 g/kg dry matter (DM)] and lower in neutral detergent fiber (NDF; 466 g/kg DM). Moreover, peanut hay was rich in Ca (12 g/kg DM) and P (1.7 g/kg DM). A feeding trial was conducted to investigate the effect of substituting wheat straw with peanut hay on nutrient intake, digestibility, and N utilization. Four adult Ramghani (Kaghani × Rambouillet) wethers (60?±?2.5 kg body weight) were randomly assigned to the four dietary treatments according to a 4?×?4 Latin square design. The four rations were formulated on isonitrogenous and isocaloric bases and differed in the proportion (in grams per kilogram DM) of wheat straw/peanut hay, i.e., 700:0, 460:240, 240:460, and 0:700. The replacement of wheat straw with peanut hay increased the intakes of DM (P?<?0.001), NDF (P?<?0.01), and N (P?<?0.001). Moreover, apparent in vivo digestibility of DM, NDF, and CP increased (P?<?0.001) with the increasing proportion of peanut hay in the ration. Nitrogen retention in the body increased (P?<?0.01; 3.2 to 8.1 g/day) with the replacement of wheat straw with peanut hay. These findings showed that substitution of wheat straw with peanut hay can improve DM and nutrients intake, digestibility, and N retention in sheep.  相似文献   
8.
There is increasing interest in sustainable land use in the tropics to optimize animal production while also reducing methane (CH4) emissions, but information on nutritive value and CH4‐emission potential of tropical forage species is limited. Samples of 24 grasses and five other forages were collected during the main rainy season on randomly positioned quadrats in semi‐arid grassland in the Mid Rift Valley of Ethiopia. Samples were pooled by species, analysed for chemical composition and incubated with rumen fluid to determine total gas and CH4‐emission potentials using a fully automated in vitro gas production apparatus. Organic matter digestibility (OMD) and metabolizable energy (ME) contents were calculated from chemical composition and gas production data. Large variability was observed among forages for all nutritional variables considered. The grasses Eleusine multiflora, Pennisetum stramineum, Dactyloctenium aegyptium, Eragrostis aspera, Cenchrus ciliaris and Eragrostis cilianensis showed relatively high OMD (68–72%) and ME values (9·1–10·2 MJ kg?1 dry matter). Melinis repens, E. multiflora and the non‐legume forb Zaleya pentandra showed relatively low CH4 to total gas ratios; these species may have potential for use in low CH4‐emission forage diets. Acacia tortilis fruits had high content of crude protein and moderate ME values, and may be an ideal feed supplement for the grazing ruminant. Sodium content was below the recommended level for ruminants in all the forage species. Overall, the pasture stand during the main growing season was evaluated as having moderate nutritional quality.  相似文献   
9.
The objectives were to determine browse species preference of goats using dry matter intake (DMI) as a proxy, to compare preference when offered in combination with polyethylene glycol (PEG) and to establish relationships between browse species intake and chemical compositional data. Air‐dried leaves of Acacia etbaica, Cadaba farinosa, Capparis tomentosa, Dichrostachys cinerea, Dodonaea angustifolia, Euclea racemosa, Maerua angolensis, Maytenus senegalensis, Rhus natalensis and Senna singueana were used. Two cafeteria trials, each lasting 10 days, were conducted using four local mature male goats of 2–2.5 years receiving a daily ration of grass hay (4% of body weight) and 200 g wheat bran. In trial 1, goats were offered 25 g of each browse species for a total of 30 min with intake, time spent on consumption and the number of visits to specific browse species recorded at 10‐min intervals. In trial 2, the same procedure was followed except that 25 g of PEG 4000 was added to the daily wheat bran ration. Crude protein and neutral detergent fibre in browse species ranged from 69.0–245.5 to 159.8–560.6 g/kg dry matter (DM) respectively. Total phenols and total tannins contents ranged between 3.7–70.6 and 2.5–68.1 mg tannic acid equivalent/g DM, respectively, and condensed tannins 1.7–18.4 Abs550 nm/g DM. Preference indicators measured in the first 10 min of browse species intake differed significantly among browse species and with PEG (p < 0.0001). Principal components explained 69.9% of the total variation in browse species DMI. Despite the high tannin levels, D. cinerea, R. natalensis and A. etbaica were the most preferred species regardless of PEG presence. Tannin levels at the observed browse species DMI did not determine preference, instead, preference appeared to be based on hemicellulose. Determining browse species preference is essential to exploit them to improve nutrient utilization and control parasites in goats.  相似文献   
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