A study to identify and estimate the prevalence of parasites of local chickens in a semi arid area of Kenya was conducted
between March 2005 and August 2006. Three hundred and sixty (360) local chickens purchased from Yathui division of Machakos
were examined. Of those, 93.3% had helminths. Nematodes were recovered in 268 (74.4%) chickens whereas 245 (68.1%) had cestodes.
Tetrameres americana (37.7%), Ascaridia galli (33.3%) and Heterakis gallinarum (22.8%) were the most important nematode species identified. Raillietina echinobothrida (33.3%) and Davainea proglottina (19.4%) were the two most important cestode species identified. Two coccidia species, namely Eimeria necatrix (6.7%) and E. tenella (16.7%) were isolated and identified as per location in the digestive system. Important ecto-parasites identified included
Echidnophaga gallinacea (76.7%), Menacanthus stramineus (79.4%) and Dermanyssus gallinae (60.0%). Endo-parasites (helminths and coccidia) occurred in significantly (p < 0.05) higher frequencies during the wet season
than during the dry season. On the contrary, ecto-parasites were significantly (p < 0.05) more fequent during the dry season.
Male chickens generally exhibited increased odds for the occurrence of parasites than female birds. Further investigations
are required to establish a plausible explanation for this. Overall, parasitism was a big constraint to chicken productivity
in the study area. Urgent integrated parasite control approaches should be initiated to address parasitism in chickens in
the Yathui cluster. 相似文献
Two experiments were carried out in Syria with the purpose of investigating to which extent the effects of including 30 % olive cake (replacing parts of forage and concentrate) or tomato pomace (replacing concentrate) in the diet, described under controlled on-station conditions, can be recovered on farm. A total of 180 lactating Awassi ewes (three farms per experiment, 15 ewes per treatment) were fed either control diets or test feed diets over a period of 7 weeks. Milk yield was measured bi-weekly and milk composition was analysed for gross physicochemical composition and fatty acid (FA) profile. Both feeds reduced milk yield (?10 %) and milk protein content, whereas milk fat content was increased by tomato pomace. Both feeds resulted in similar changes in milk FA profile, namely less saturated and polyunsaturated FA and more monounsaturated FA including 18:1 trans FA. Tomato pomace and olive cake also resulted in increased n-6:n-3 FA ratios, while the proportion of the conjugated linoleic acids was not affected by either treatment. In conclusion, the response of the ewes on farm was clear and similar in nature for most of milk-related traits as that found on station, but lower in magnitude.
Drought is becoming a major threat to rice farming across the globe owing to the depletion of water tables in rice-growing belts. Drought affects rice plants at multiple stages, causing damage at morphological and physio-biochemical levels, leading to severe losses that exceed losses from all other stresses. The amalgamation of conventional breeding methods with modern molecular biology tools and biometrical methods could help accelerate the genetic gain for drought tolerance in rice. Many drought-tolerance traits with genetic determinants have been identified and exploited for tolerance rice variety breeding. The integration of genome-wide association study and genomic selection tools with speed breeding shortened the breeding cycle and aided in rapid improvement of genetic gain. In this review, we emphasized the progress made through classical breeding as well as the limitations and usefulness of current genomic methods in improving drought tolerance. We briefly addressed methods for identifying genetic determinants for drought tolerance and deploying them through genomics-assisted breeding programmes to develop high-yielding drought-tolerant rice cultivars. 相似文献
This study investigated the effects of arbuscular mycorrhizal (AM) colonisation by Glomus clarum on growth and fruit yield of pepper (Capsicum annum cv. 11B 14) grown at high salinity. The experiment was conducted in pots containing a mixture of perlite and sand (1:1, v/v) under glasshouse conditions. Treatments were: (1) no added NaCl without arbuscular mycorrhizae (NS-AM), (2) no added NaCl with arbuscular mycorrhizae (NS + AM), (3) added 50 mM NaCl without arbuscular mycorrhizae (S1-AM) and (4) added 100 mM NaCl without arbuscular mycorrhizae (S2-AM), (5) added 50 mM NaCl with arbuscular mycorrhizae (S1 + AM) and (4) added 100 mM NaCl with arbuscular mycorrhizae (S2 + AM). The NaCl treatments reduced pepper shoot and root dry matter, and fruit yield compared with the non-saline treatments. The concentrations of N, P and K, in the leaves were significantly reduced by salinity stress, however, mycorrhizal colonisation of the salt-stressed plants restored leaf nutrient concentrations to the levels in non-stressed plants in most cases. AM inoculation improved pepper growth under salt or saltless conditions and reduced cell membrane leakage. 相似文献
Detection of infectious hypodermal and hematopoietic necrosis virus (IHHNV) in shrimp is complicated by the fact that certain virus-related sequences are integrated into the genome of Penaeus monodon in some parts of the world, which has been reported so far from Africa and Australia. In this study, we evaluated the highly specific and sensitive diagnostic primer sets for detection of infectious IHHNV and integrated virus-related sequence in 177 samples of P. monodon from India. A nested primer set, IHHNV648F/R and IHHNV309F/R was used to specifically detect infectious IHHNV and not the virus-related sequences. IHHNV was detected in 67.4% postlarvae (PL) and 34% adult samples using this primer set. The OIE recommended primers IHHNV392F/R and IHHNV389F/R gave positive reaction for 86.7% PL and 67% adult samples, while the primer pair 77012F and 77353R gave positive reaction with 46.7% PL and 20% adult samples. These primers were found to detect virus-related sequence integrated into the shrimp genome. The analysis of virus-related sequence by MG831F/R primers showed that 33.7% PL and 31.7% adult shrimp possessed Type A virus-related sequence. 22.8% PL and 10.5% adults had both IHHNV and Type A virus-related sequence. Cloning and sequencing 832 bp virus-related sequence from P. monodon from India revealed presence of five shrimp DNA markers between 439 and 825 bp. This study is the first conclusive report on the presence of Type A virus-related sequence in P. monodon from India. 相似文献
The counter-immunoelectrophoresis test (CIEPT) was compared with the rose bengal plate test (RBPT) and the serum agglutination test (SAT) in the diagnosis of brucellosis in 241 sheep. The total number of animals positive by one or more of the tests used was 106. Sixty animals were positive by all tests, while 87, 79 and 80 were positive by CIEPT, RBPT and SAT respectively. Based on the assumption that animals with an SAT titre of 40 I.U./ml or above were true positives, the CIEPT had a sensitivity of 82.5% and a specificity of 78.3% compared to 96.5% and 87% respectively, demonstrated by the RBPT. CIEPT might be used in flocks without clinical evidence of ram epididymitis if a test to supplement RBPT were required; but it would only partially replace SAT. Sera positive in RBPT but negative in CIEPT would have to be tested by SAT. With this combination, only about 22% of sera positive in RBPT would need to be further tested by SAT. 相似文献
This paper includes a review of international sustainable forestry development followed by an analysis of forest policies
in Bangladesh. There have been four different government forest policies in Bangladesh since 1894. The first two forest policies
(1894 and 1955) were exploitative in nature. Most of the regulatory documents were developed during the first two policy periods.
The third forest policy instituted in 1979 by the sovereign Bangladesh government had contradictory elements and mutually
inconsistent policy statements. It addressed for the first time forestry extension through mass motivation campaign. Current
forest policy formulated in 1994 has been considered to be the most elaborate policy in the history of the country. Under
this policy, participatory social forestry has been institutionalized in Bangladesh. The analysis shows that, although it
is possible to attain the stated policy targets, progress is slow and is blocked on several fronts. A number of identified
technical, managerial and logistical problems are hindering policy and program implementation. In addition, corruption contributes
to the observed problems. The real strength of Bangladesh forestry is locally based, participatory forestry, co-management
of protected areas and highly motivated people who increasingly recognize the need for a healthy forest ecosystem that will
provide future economic stability. Because it is the rich homestead forests of Bangladesh that generate the majority of commercial
forestry products, it is important that education continues at the grass-roots level. In addition, educated forestry and environment
professionals have been identified as the future driving forces towards better, and sustainable, forest management. Results
of this study make it clear that Bangladesh and other developing countries are not presently in a position to accept and adopt
internationally derived forest policies due to inadequate institutional support, political instability and poor governance.
Therefore, along with development of criteria and indicators of sustainable forest management and forest certification, international
policy scientists must consider institutional development, professional skill development, identification and adoption of
indigenous technology and long-term financial support in developing countries. Without these, all international processes,
policies and directives will be of little value and produce few substantive results. 相似文献