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21.
Thirty-seven ostrich chicks raised artificially had their weights, lengths of metatarsus and heights measured weekly from hatching to the 16th week. Despite weight loss during the first week due to utilization of egg yolk by the chicks, the chicks showed an exponential growth up to the twelfth week with an overall mean weekly weight gain of 1.3 kg. Female chicks showed a superior mean weekly gain of 1.6 kg compared to 1.2 kg for males. The metatarsal length grew rapidly at a weekly rate of 2.5 cm, but began to decline in the 11th week even though the weights and heights of the chicks were still increasing. The correlation coefficient between body weight and metatarsal length was 0.97. Individual chicks also maintained their respective heavy or light weight hierarchies throughout the study period. Thus isolation of chicks into groups by weight and raising them separately could have a role in the artificial rearing of ostrich chicks. Furthermore, ostrich chick rearing may be improved by regularly weighing chicks as a means of detecting changes in the growth patterns.  相似文献   
22.
Tropical Animal Health and Production -  相似文献   
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24.
This paper reports on an empirical investigation about regional economic impacts by the promotion of wood chip utilization in Maniwa city, Japan. We clarify the estimated potential of regional economy development by using input–output analysis for Maniwa city. The result indicates that 315 million JPY of woody chip products can be estimated to generate roughly 448 million JPY of direct, indirect, and induced economic effects. The value of 448 million JPY was equivalent to about 0.2 % of total production value in Maniwa. It is also expected to create approximately 21 jobs by promotion of wood chip utilization. We examined the regional economic impacts on the woody biomass utilization, and evaluated to estimate direct, indirect and induced economic effects, and job creation to clarify the economic impact on Maniwa. We will leave the negative economic effects and the environmental impacts in the process of woody biomass utilization as a future task.  相似文献   
25.
A cross-sectional study of prevalence of antibody against Brucella organisms was conducted among donkeys in three local government areas of Yobe State, northeastern Nigeria. Three hundred adult donkeys of both sexes were sampled, with 100 samples each from local government areas Bursari, Gaidam, and Machina. The overall serological prevalence of brucellosis among donkeys in the three local government areas by both rose bengal plate test (RBPT) and microtiter serum agglutination test (MSAT) was 15 (5.0%), of which five (1.7%) were male and 10 (3.3%) were female donkeys. The overall prevalence by competitive enzyme-linked immunosorbent assay (cELISA) was 10 (3.3%), of which four (1.33%) were male and six (2.0%) were female donkeys. There was a significant association between the female sex of the donkeys and the serological reaction to RBPT, MSAT, and cELISA (P < .05). Of the 100 sera sampled from Bursari, five (5%) were positive by RBPT/MSAT, which comprised two (2%) male and three (3.0%) female donkeys. There was no significant association between the sex of the donkeys and the serological reaction (P > .05). Of the 100 samples from Gaidam, four (4.0%) tested positive by RBPT/MSAT, of which one (1.0%) was male and three (3.0%) were female donkeys (P < .05). Six (6.0%) of the 100 donkey sera samples from Machina tested positive by both RBPT and MSAT, which comprised two (2.0%) male and four (4.0%) female donkeys. There was no significant association between the male sex of the donkeys and the serological reaction (P > .05); however, there was a significant association between the female sex of the donkeys and the serological reaction to both RBPT and MSAT (P < .05). Of the 100 samples from Bursari and the 100 samples from Gaidam, three (3%) from each were positive by cELISA, which comprised one (1%) male and two (2%) female donkeys. There was no statistically significant association between the sex of donkeys and the serological reaction (P > .05). Of the 100 samples tested from Machina, two (2%) male and two (2%) female donkeys were positive for Brucella antibodies by cELISA. No statistically significant association was demonstrated between the sex of the donkeys and the serological reaction to cELISA (P > .05). Because of the importance of donkeys to humans as a source of draft power, infected donkeys could be a source of Brucella infection to humans through close contact, through the respiratory system via contaminated dust or droplets, and through aborted fetuses and discharges from the genitalia.  相似文献   
26.
Oil palm is continually being improved via controlled crossing of selected palms to ensure sustainable yields and productivity. As such, correct parental assignment is important as the presence of illegitimates will compromise the progress of improvement. In the present study, we determined the optimal number of microsatellite (SSR) markers for detection of illegitimates in selected oil palm crosses with high confidence. Determining the optimal number of markers to assign parentage will ensure that the DNA fingerprinting will be cost effective for routine use as a quality control tool in oil palm improvement programs. Here, we evaluated a wide range of crosses that included a cross derived from wild germplasm palm. The results revealed that markers with high PIC are informative and detect most of the alleles present in a cross, including those exhibited by the illegitimates. A larger number of optimum sets of markers are needed to detect all illegitimates for crosses with higher levels of genetic diversity. The optimal number of polymorphic SSR markers determined in the present study can ensure that appropriate quality control is implemented for oil palm improvement programs.  相似文献   
27.
Landscapes are considered to be complex systems that are hierarchically structured and spatially scale-dependent. Geopedology allows a systematic approach in geomorphic analysis for soil mapping that extrapolates the results obtained at sample areas up to similar units. This paper examines the influence of sampling intervals on the accuracy of geopedological results in the Borujen region, Central Iran. After a primary interpretation of the study area on air photos (1:20 000), a geomorphic unit that encompassed the maximum surface of the sample area (and also the study area) was selected and was surveyed at three different scales: 500, 250 and 125 m intervals. The credibility of generalization of the results of the geopedological approach for the studied unit was tested by comparison with three profiles in a similar unit outside the sample area, named the validation area. Although the type of mapping unit in the sample area and the validation area was the same (complex) at the three different scales, the dominant soil in the validation area was different in comparison with the sample area at 125 and 250 m intervals. The results indicate that the geopedological approach to soil mapping is better carried out in reconnaissance or exploratory surveys. Comparison of soil types between the unit in the sample area and the validation area at three scales indicated that by increasing the taxonomic accuracy, the hidden aspects of the soils may be more identifiable. Therefore, although the geopedological approach tries to distinguish more homogeneous soil mapping units, it still is not able to fully define and represent the variability and apparent chaotic nature of the soils. We recommend further investigations on different techniques of stratifying the landscape in order to better analyze and understand the soil forming processes and soil variability and to improve sampling and mapping approaches.  相似文献   
28.
Conceptual models are suitable for describing internal relationships of complex systems, including soil. We used conceptual models, the Jenny's and Johnson and Watson-Stegner's models to understand the formation and evolution of soil. We studied 20 pedons in granitic hilly lands, loessial piedmont, and piedmont plain in southern Mashhad, northeast Iran. These soils were characterized by high levels of gypsum, especially in the granitic saprolites, which suggested the importance of the wind in shaping the soil structure. Jenny's model is a developmental and equilibrium model, which only describes the state of the soil formation factors and considers that each bioclimatic zone has a specific climax soil. It focuses on the genesis of the surface soil and is not suitable for buried soils and paleosols. Johnson and Watson-Stegner's model describes soil as a product of progressive and regressive processes due to horizonation or haploidization. Progressive processes during the last interglacial cycle created a well-developed paleosol with an argillic horizon in all landforms, except the piedmont plain. Developmental soil up-building by aeolian addition led to gypsum enrichment of the granitic saprolite. Erosion decreased soil thickness and exposed the argillic horizon. The Last Glacial Maximum led to greater deposition of loess, covering the paleosol. Humidity was higher during the early Holocene than today, leading to the development of a Bk horizon. This horizon was preserved in the stable surfaces of granitic hilly land and in the loessial piedmont, but buried on the piedmont plain via the deposition of alluvial sediments. Jenny's model could be used for current soil formation factors, whereas Johnson and Watson-Stegner's model required morphological characteristics of pedons for interpretation.  相似文献   
29.
Zebrafish sperm cryopreservation is a fundamental methodology to manage and back-up valuable genetic resources like transgenic and mutant strains. Cryopreservation usually requires liquid nitrogen for storage, which is expensive and hazardous. Our objective was to evaluate if electric ultrafreezers (??150 °C) are a viable alternative for zebrafish sperm storage. Zebrafish sperm was cryopreserved in the same conditions (??20 °C/min), stored either in liquid nitrogen or in an ultrafreezer, and thawed after 1 week, 1 month, and 3 months. Sperm motility, membrane integrity, and fertilization ability were assessed. There were no significant differences in motility and hatching rate throughout storage time. Additionally, we aimed at understanding if cryopreservation directly in an ultrafreezer (??66 °C/min) could improve post-thaw sperm quality. Freezing at ??20 °C/min was performed as before, and compared to samples cryopreserved with a fast cooling rate by placing directly in an ultrafreezer (??66 °C/min). Sperm quality was assessed according to motility, viability, DNA fragmentation, and apoptosis (annexin V). The ??66 °C/min cooling rate showed significantly higher membrane and DNA integrity, and lower number of cells in late apoptosis in comparison to the other treatments. This study showed that zebrafish sperm cryopreservation and storage in an ultrafreezer system is possible and a fast cooling rate directly in ultrafreezer improves post-thaw sperm quality.  相似文献   
30.
The vine bud moth, Theresimima ampellophaga (Bayle-Barelle 1808) (Lepidoptera: Zygaenidae; Procridinae), is a pest on grape vine, Vitis vinifera (L.), and on the ornamental vine Parthenocissus quinquefolia (L.) and other Parthenocissus species. Its recent distribution in Europe is relatively well known, but there is a paucity of locality data for Turkey. As a consequence, we began a large-scale investigation into its distribution and seasonal activity in this country in 2008. The main tools for these investigations were pheromone traps that were baited with the synthetic pheromone of the species, viz. (2R)-butyl (Z7)-tetradecenoate. As a result of field work carried out in the eastern Mediterranean region of Turkey in 2008 and 2009, Th. ampellophaga was recorded in five provinces, viz. Adana, Mersin, Hatay, Kahramanmara? and Kilis. The only province where the pest was not found was Gaziantep. Theresimima ampellophaga produces one or two generations per year, depending on the local conditions and other unknown factors. The moths of the first generation fly in June, while those of the second generation occur in August. To the best of our knowledge the present paper provides the first well-documented evidence of the occurrence of a second generation of the vine bud moth in Turkey.  相似文献   
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