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121.
The effect of essential oil (EO) supplementation on carcass characteristics of Japanese quails and interactions between ingredients and intestinal morphology were investigated in this study. A total of 250 quails were fed different diet: D1, basal diet (BD); D2, BD plus palmarosa oil (PO; 100 µg/kg diet); D3, BD plus lemon myrtle oil (LMO; 100 µg/kg diet); D4, BD plus α-Tops (mixture of α-terpineol, cineole and terpinene-4-ol; 100 µg/kg diet); and D5, BD plus cyclodextrin. Overall growth performance was determined at multiple time points during 35 days of experiment. Carcass characteristics (fatty acid, pH and colour), intestinal morphology and the expression levels of meat quality-related genes including the insulin-like growth factor (IGF-1), myogenin and avian uncoupling protein (avUCP) were examined at the end of the trial. Additionally, intestinal microbiome of quails was studied by next-generation sequencing-based culture-independent analysis. Although the inclusion of EOs into the diet had no effect on the growth performance of quails and the microbial profile, the significant changes in pH24 and colour (a*) of the quail's breast muscle (p < .05) in the group receiving PO were observed. Additionally, oleic acid content in the breast muscle was significantly higher in the EOs supplemented groups (p < .01). Quails fed the PO supplemented diet had higher villus and relatively rich in oleic acid. The expression levels of IGF-1 and myogenin genes in quail's muscle were not affected, but the expression of avUCP gene was significantly lower in quails fed with LMO and α-Tops (p < .05). The results demonstrated variable effects of these treatments on intestinal morphology. Taken together, dietary inclusion of EOs is found to be beneficial and hence can be recommended for improving the quality of poultry meat.  相似文献   
122.
Summary The extent to which evapotranspiration (ET) of Valencia citrus trees is affected by differing soil water depletions (SWD) and soil salinity regimes was determined during five seasons during which soil salinity levels varied. Three weighing lysimeters, each with a 14 year old tree, were used to measure daily ET and to schedule irrigation to maintain SWD at maxima of 15, 75 and 150 mm respectively. Tensiometers and salinity sensors were used to indicate the in situ soil matric and soil solution osmotic potentials. Total soil water potential was calculated from tensiometer and salinity sensor readings weighted for root density with depth. The total of these for the summer months was found to be linearly related (Fig. 5) to the mean ET/Ep (Ep=A-pan evaporation). The slope and threshold of ET reductions with decreasing soil water potential for the low frequency irrigation treatment (150 mm SWD) show good agreement with the slope and threshold of yield decrease that is calculated from soil salinity in the lysimeter using previously reported salinity-yield relationships. The reduced water uptake due to increasing soil salinity has important implications for soil salinity control, since the lower uptake should in theory increase the leaching fraction. This implies a degree of self adjustment to the leaching fraction when irrigating with increasingly saline waters if water applications are scheduled as for non-saline conditions.  相似文献   
123.
Studies describing habitat use in animal species need to take into account detectability of individuals in order to reach more robust conclusions. However, the importance of detectability in habitat selection analyses of rare and cryptic species has received little investigation, although robust methods for estimating detectability have been made recently available. Understanding habitat requirements should be an important management tool for the conservation of the red-crested pochard (Netta rufina), a rare duck species in France and Europe. Three different lake samples (82 lakes in total) were conjointly used in 2000 and 2001 to assess the species habitat requirements, using its presence, density and hatching dates as response variables. Risk of false absence was estimated using the double-observer approach at less than 0.001. A robust-design approach produced estimates of individual brood detectability (0.545, SE = 0.053). Observed red-crested pochard densities were adjusted to time dependent detectabilities, and modelled as a function of habitat variables. Habitat fragmentation and low permanent water levels negatively affected brood densities. Interestingly, these variables were not retained when modelling the unadjusted densities. This analysis showed that investigating temporal variation in brood detectability was a crucial prerequisite in the study of this rare species’ habitat requirements. More generally, it strongly suggests that integrating detection probability and its variations in habitat use analyses of cryptic species of conservation concern may be an essential methodological step to reach more valid conclusions on habitat management.  相似文献   
124.
This work is an attempt to establish the morphogenesis of four hydromorphic profiles (Plateau des Fagnes, Eastern part of the Belgian Ardennes). Various scientifical approaches were used, namely geomorphology, mineralogy and palynology.The aim was to show that very sharp discordances may appear between “inherited” profile morphology and the present state of hydromorphy characterized by vegetation, humus forms, and physico-chemical measurements, such as redox potential and oxygen diffusion flux intensity (see partie II)  相似文献   
125.
126.
In the water-scarce environment of South Africa, drought-tolerant eucalypt species have the potential to contribute to the timber and biomass resource. Biomass functions are a necessary prerequisite to predict yield and carbon sequestration. In this study preliminary biomass models for Eucalyptus cladocalyx, E. gomphocephala and E. grandis · E. camaldulensis from the dry West Coast of South Africa were developed. The study was based on 33 trees, which were destructively sampled for biomass components (branchwood, stems, bark and foliage). Simultaneous regression equations based on seemingly unrelated regression were fitted to estimate biomass while ensuring additivity. Models were of the classical allometric form, ln(Y) = a+x1ln(dbh)+x2ln(h), of which the best models explained between 70% and 98% of the variation of the predicted biomass quantities. A general model for the pooled data of all species showed a good fit as well as robust model behaviour. The average biomass proportions of the stemwood, bark, branches and foliage were 60%, 6%, 29% and 5%, respectively.  相似文献   
127.
The genetic variability of 46 accessions of the Lima bean (P. lunatus L.) including 16 wild forms and 30 landraces belonging to the three cultigroups Big lima, Sieva, Potato, and their intermediates, was evaluated using RAPD (Random amplified polymorphic DNA) markers. Twelve oligonucleotide primers produced 172 RAPD markers which allowed the differentiation of two main groups: the mesoamerican and the andean groups. This was confirmed by an AMOVA analysis which indicated that 37.7% of the variation was found between these two groups. For each botanical form (wild and cultivated), the molecular markers showed that small-seeded types (i.e. Sieva and Potato types and their related wild forms) had a wide distribution (from Mexico to Argentina) while the large-seeded types (Big lima type and its related wild forms) were circumscribed to the narrow west-coastal region from Ecuador to Bolivia. The results are in favour of an independent domestication process within the two groups, as the differentiation between mesoamerican and andean accessions was found to occur in both wild forms and landraces. Within each of the two main groups, wild forms and landraces were also found to be genetically differentiated and higher genetic diversity was observed among landraces than among wild forms. Within the mesoamerican landraces, low but significant differentiation between the Sieva and Potato cultigroups was observed. Some suggestions and hypotheses are discussed about evolution of the two small-seeded types. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
128.
129.
The Kinangop highland grasslands, the world stronghold of the endangered Sharpe's longclaw (Macronyx sharpei), consist almost entirely of privately owned land. As human population in the grasslands increases, the mean acreage of land holdings decreases and more grassland is being converted to other uses. Land subdivision information, existing human population data, and current land use data from a subset of 162 farms were used to extrapolate the past and future extent of Sharpe's longclaw habitat throughout the landscape on Kinangop Plateau. It was estimated that grasslands covered 50% of the plateau in 2000, but only 58% of the grassland area was likely to be tussock grasslands, the preferred habitat of Sharpe's longclaw. Large farms are being subdivided rapidly, and more than half of the remaining tussock grasslands are likely to be found on farms that are not large enough to support large longclaw territories. We predict that by 2010 tussock grasslands will cover only one-fifth of Kinangop, and all farms that are large enough to act as longclaw reserves are likely to have been subdivided. We propose urgent prioritisation of a network of large farms (>30 ha) for conservation action.  相似文献   
130.
Reasons for performing study: Dental disease has been shown to be a risk factor for weight loss and colic in horses. No extensive clinical studies in donkeys have investigated the potential relationship between different dental disorders, or between dental disease and systemic disorders. Objectives: To determine possible associations between dental disease and body condition score, weight loss, the need for supplemental feeding and prevalence of colic in donkeys of all ages, and to gain a better understanding of the pathogenesis of dental disease by the determination of associations between different dental disorders. Methods: A prospective cross‐sectional analysis of clinical dental examinations of 357 donkeys in The Donkey Sanctuary, Sidmouth was performed. Other epidemiological factors such as estimated age group, body condition score, weight loss, medical history and supplemental feeding were also recorded, and multiple regression analyses were performed to determine possible associations. Results: Donkeys from older age groups were more likely to have dental disease, poor body condition score and suffered previous colic episodes. The presence of dental disease was also significantly associated with weight loss, colic, low body condition score and the need for supplemental feeding. The presence of diastemata, periodontal disease, wave mouth, smooth mouth and step mouth are frequently associated with the presence of other dental disorders. Conclusions: In addition to oral‐related pain, dental disease can cause significant systemic disorders and so has increased welfare implications in donkeys. Some dental disorders promote the development of other types of dental abnormalities and thus increase the severity of dental disease in individual animals. Potential significance: Effective treatment of dental disorders slows down the progression of dental disease and decreases the risk of developing some medical disorders such as colic and weight loss that are associated with dental disease.  相似文献   
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