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1.
First of all spineless Opuntia is an important source of water for livestock in tropical regions. The water content of one-year sprouts amounted to 92.5%. 70 to 75% of dry matter of Opuntia ficus indica were crude carbohydrates, approximately 20% were crude ash. The apparent digestibility of organic matter was considerably high (70.9%), the energy content amounts to 35 and 467 EFUc per kg of fresh and dry matter respectively. Opuntias are roughage, their energy content is similar to that of grass or legumes during flowering. The protein content is too low (4.5 to 5.5% crude protein of dry matter) in order to meet the protein requirements of animals. When they had the choice rams preferred chopped fresh Opuntia (61.6% of the whole DM intake) to chopped dried Opuntia (34.7%) and whole fresh Opuntia (3.7%) apart from a certain basal diet (200 g of meadow hay and 200 g of concentrate per animal and day). If only one of the three differently treated forms of Opuntia was fed (apart from the basal diet) the sheep consumed daily 359 g of dry matter of chopped fresh Opuntia (approximately the same amount as if they had the choice, 101%), 313 g of dry matter of chopped dried Opuntia (88%) and 121 g of dry matter of whole fresh sprouts of Opuntia (34% of the total intake when they had the choice.) According to the obtained results spineless Opuntia ficus indica can be used in chopped form as an additional feed to other roughages (like grass, hay, straw) especially during the dry season.  相似文献   
2.
Ruminants adapt to periodic fluctuation in feed resources by accumulating fat stores during favourable periods. Thus, genetic variations, among ruminant genotypes, in the capacity to deposit fat could be exploited through breeding to improve animal productivity in traditional tropical production systems. Based on this premise, breed differences among weights of principal adipose depots and total body fat were estimated in Menz (n = 303) and Horro (n = 151) sheep of Ethiopia. Animals were kept on supplemental feeding, for about 3.5 months, until slaughter at about 17 months of age and pre‐slaughter live weight of 25 kg. Except the combined weight of tail and rump fat (TRF) which was similar (p > 0.05) in the two breeds, weights of subcutaneous and intermuscular fat (SIF), internal fat (IF) as well as total dissected body fat (TotDF), total ether‐extracted body fat (TotEE) and TotFAT (TotDF plus ‘residual’ fat, fat recovered by ether‐extraction from non‐adipose tissues) were significantly (p < 0.01) higher in the Menz. TotDF, TotEE and TotFAT were 1.91 ± 0.04, 2.05 ± 0.06 and 2.64 ± 0.06 kg, respectively, in the Menz and 1.50 ± 0.05, 1.44 ± 0.06 and 2.02 ± 0.07 kg, respectively, in the Horro. Implications of breed differences in fat distribution among depots, and possible consequences of genetic improvement of some of the depots on adaptation to climatic and nutritional stresses as well as some production objectives are discussed.  相似文献   
3.
Two types of locally produced live vaccines (HB1 and La Sota--lentogenic strains) and inactivated oil adjuvant (IOAV) vaccine were used to compare the efficiency of three vaccination techniques, namely drinking water, ocular and spray on broiler chicks. The ocular route of vaccination on 1-day-old chicks followed by a booster dose on the third week through the same route induced a significantly higher level of haemagglutination inhibition antibody titre (P < 0.0001). The highest mean antibody titre was log(2) 6.6 and 93.3% of the chicks were protected from the challenge. The spray technique induced a lower antibody titre (peak of log(2) 5.9) and only 53% of the chicks in this treatment survived against the challenge. The results of this study show that the ocular route is superior to the drinking water route, which is superior to the spray technique. The economic analysis result showed that the ocular HB1 and La Sota vaccine administration method to 1- and 21-day-old chicks gave the highest revenue followed by the drinking water method. In terms of total cost, the injection method required the highest cost (0.21 birr/chick) followed by the ocular method (0.18 birr/chick). The marginal cost of vaccine administration is too small compared with marginal revenues from relative effectiveness of the methods. The internal rate of return for the ocular method was very high. The results of sensitive analysis on revenues from different vaccination methods indicate that a 25% reduction in broiler price reduces the marginal revenue from the ocular method by 12 487 birr but this still does not prove that the ocular method is economically viable for small- and medium-scale poultry farms.  相似文献   
4.
The study was conducted in three regional states of Ethiopia: Amhara, Oromia, and Addis Ababa from August 2008 to April 2009 with the objectives of identifying the genetic diversity of serotypes and topotypes in Ethiopia, and determining the attack rate and associations of potential risk factors with foot-and-mouth disease (FMD) seropositivity. A total of 496 cattle were clinically and serologically examined for presence of specific lesions and nonstructural protein for FMD, respectively. Of which, 140 (28.2%) manifested clinical signs and lesions suggestive of FMD, and 219 (44.2%) were seropositive. From a total of 7,781 animals observed and recorded on a designed format in six districts, 1,409 (19.6%) were infected, and 15 (0.12%) died during outbreaks of FMD. Epidemiological investigations revealed that the morbidity rate of the disease was 21.1% in Akaki-kality sub-city, but the mortality rate was <2% in all districts. Furthermore, the mortality and case fatality rates were relatively higher, 1.6% and 8.9% in calves than the other age groups, respectively. From a total of 33 bovine epithelial tissue-cultured samples, 19 (57.6%) showed CPE for FMD virus, in which 16 samples had serotype O and EA-3 topotype, while three samples had found serotype A, Africa topotype, and G-VII strain. Various strains of FMD viruses were isolated in Ethiopia in this study, and therefore, further detailed studies on the evaluation of available vaccines and the development of a vaccine which contains cocktails of antigens of FMD virus strains in the country should be encouraged.  相似文献   
5.

Marek’s disease (MD) is a lymphoproliferative and neuropathic disease of domestic chickens and less commonly, turkeys and quails, caused by a highly contagious, cell-associated, oncogenic herpesvirus. In Ethiopia, MD is believed to be introduced with importation of exotic and crossbred to improve the poultry production and has been reported to be a potential threat to the poultry sector both in backyard and commercial farming systems. This study was aimed at isolation and molecular analysis of MD virus isolates circulating in chicken population in the central part of Ethiopia where commercial farms are populated. From September 2013 to January 2014, clinical and post-mortem examination were conducted on diseased chickens suspected of MD virus infection. Representative spleen and feather follicle samples were collected following sterile procedure, and infectious virus isolation was performed using primary chicken fibroblast cell culture. Cell culture inoculated with suspension of pathological samples developed characteristic MD virus cytopathic effect of rounding of the cells and small plaques. Further analysis of the virus was conducted by conventional PCR amplifying the ICP4 gene fragment from eleven tissue samples using MD virus specific primers. PCR products were further sequenced and analyzed. Nucleotide sequence similarity search of the local isolates resulted a high degree of sequence similarity with Gallid Herpes virus type 2 strain (Marek’s disease virus type 1, JN034558). To our knowledge, the present study is the first report conducted on virus isolation and molecular characterization of MD virus isolates circulated in Ethiopia. Eleven ICP4-like gene fragment (318 bp) sequences generated in the present study were uploaded in the public database (KU842366–76). Further research on virus isolation, genetic characterization, and infection dynamics is recommended targeting chickens of all age groups reared in different agro-ecological zones under different production system.

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6.
The role of land registration in reducing rural poverty has been debated for several decades. This article analyses the impacts of land registration on land rentals, security of land tenure, disputes over land, use of credit facilities from formal financial institutions and gender access and control over land. Our findings are based on data collected between April and December 2011 in irrigation systems in three regional states of Ethiopia using in‐depth interviews and field surveys. Land registration has a positive influence on land rentals by reducing the fear of landholders in losing land to renters. Important benefits of land registration also include enhancing tenure security through ensuring usufruct rights over land and addressing the conflicts that arise from the competition to access irrigable land. Joint land titling secures women's access to land and encourages women's decision‐making on land rentals, input use, cropping patterns and the marketing of harvest from irrigable plots. While land registration allows for improved tenure security, gender equity and reduced disputes over land, it does little to facilitate access to credit or increase the use of farm inputs. The findings suggest that more work needs to be carried out to translate the benefits of land registration into improved livelihoods by increasing investment in farm inputs, production of high value, off‐season crops and increase market participation. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
7.
In the Ethiopian highlands, communal grazing lands are one of the major land uses, and are source of livelihood for the rural people. Free and uncontrolled grazing in the communal grazing lands is the dominant grazing system. The traditional uncontrolled and free grazing system has caused severe degradation of the grazing lands. As a result, communities have started to establish exclosures and support the restoration of degraded communal grazing lands. Studies have shown that exclosures are effective to restoring degraded communal grazing lands and improving ecosystem services. However, studies that investigate the changes in aboveground biomass following the establishment of exclosures and compare it with fuelwood demand of the beneficiaries in our study area is lacking. Therefore, our study aimed at:(1) quantifying yearly biomass accumulation in exclosures and compare it to fuelwood demand of households that manage the exclosures;(2) assessing household energy sources and their consumption levels. To monitor changes in biomass production with over time, replicated(n = 3) 5 and10 year-old exclosures were sampled. To investigate fuelwood sources and consumption patterns, household surveys, key informant interviews and focus group discussion were conducted. Our results demonstrated that total biomass production increased with exclosure age. In both exclosure, biomass production from Vachellia etbaica was significantly(p \ 0.05) greater than that from Euclea.racemosa. Average daily fuelwood consumption per person was(0.63 ± 0.2) kg day-1. This means that the total biomass(27.5 Mg year-1) obtained from 114.6 ha of exclosures covers only 9.4% of yearly fuelwood demand of the residents who manage the sampled exclosures. Nearly all respondents(95%) confirmed that they travel more than10 km day-1 to gather fuelwood from surrounding degraded forest patches. We recommend plantings of fast growing native tree species within exclosures and around homesteads to provide a sustainable fuelwood supply and using improved stoves to address the problem of fuelwood shortage. District agricultural offices could provide seedlings of native plant species, while communities provide unpaid labour for planting and managing plantations.  相似文献   
8.
In Ethiopia, lack of quality forage in adequate quantities is a major constraint to livestock productivity. Fast growing N2 fixing Sesbania have shown great promise both as high quality fodder and green manure. The objective of this study was to evaluate and select among the species S. macrantha, S. rostrata, S quadrata and S. sesban for fodder yield, quality and green manure potential. The field experiment was conducted on a light soil (loam, Alfisol) and a heavy soil (cracking type clay, Vertisol) at Debre Zeit (9° N and 39° E, 45 kms SE of Addis Ababa). There were two cutting treatments: cutting once at ground level or cutting twice at 50 cm (first, 65 days after sowing; second, 40 days later). A two-factor factorial in randomized block design was used. S. macrantha performed better on the light soil producing the highest dry matter (DM) yields of leaf (2.8 t/ha), stem (6.3 t/ha) and total nitrogen (151 kg/ha) in 105 days than the rest of the species. Most species performed poorly on the heavy soil. S. quadrata, however, showed better adaptability to the heavy soil (5.5 t/ha DM) than any of the other species. The lowest DM yield was recorded for S. rostrat which could be due to poor nodulation. Cutting twice over the 105 days growth period caused a drastic reduction in DM yield, but resulted in higher leaf-to-stem ratio and total N yield. The nutritional composition of all the species was within an acceptable range for livestock requirements. N content (4%) and IVDMD (over 70%) were high. S. macrantha had superior overall performance and seems promising both as high quality fodder and green manure crop. Under rain-fed conditions, cutting once was better than cutting twice particularly for S. macrantha. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
9.
宁波市周年供笋技术研究   总被引:5,自引:0,他引:5  
首先通过竹种搭配,改主产毛竹笋为多品种竹笋的周年供应;其次是采取科学施肥、合理挖笋等技术,使毛竹春季产笋为四季产笋;第三采用反季节栽培等技术,使竹笋供应时间从春季到四季,竹笋品种多样化,竹笋的产量和质量有很大提高,特别是毛竹鞭笋亩产达650kg,毛竹冬笋亩产超过千斤,雷笋亩产达3000kg。  相似文献   
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