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1.
To improve genetic gain of breeding programs for village poultry production, breeding schemes with observations obtained in village production systems using individual (VIO) and group recording (VGO) were examined under different levels of genotype-by-environment-interactions (GxE). GxE was modeled by varying the correlation between traits measured in the breeding station and village environments for bodyweight (rg_BW) and egg production (rg_EP). Relative and absolute genetic gains obtained from VIO and VGO were used for comparison between the schemes. Results showed that village observations significantly improved genetic gains compared to the scheme without birds tested in the village. The improvement was only slightly larger with individual observations than with group observations. Higher rg_BW and rg_EP led to lower relative genetic gain, but a higher absolute gain of VIO and VGO. It is recommended to apply a breeding scheme using group recording of village performance when strong GxE in breeding for village poultry is expected.  相似文献   
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A new nematode species, Rhabdochona longleyi sp. n. is described from the intestine of two species of blind catfishes, Trogloglanis pattersoni Eigenmann (type host) and Satan eurystomus Hubbs et Bailey (both fam. Ictaluridae, Siluriformes) from the subterranean waters (artesian wells penetrating San Antonio pool of Edwards Aquifer) of Texas, USA. It is characterized largely by the presence of only six anterior teeth in the prostom, simple deirids, by the shape and length of spicules (0.42 to 0.50 mm and 0.093-0.102 mm), shape of the tail tip (rounded), and by filamented eggs. R. longleyi probably adapted to the environment of the aquifer by utilizing available troglobitic crustaceans instead of aquatic insects as an intermediate host.  相似文献   
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Historical records provide information to land managers and landscape ecologists attempting to understand current trajectories in altered landscapes. In this study, we synthesized a heterogeneous array of historical sources to reconstruct historical land cover in California’s Santa Clara Valley (a.k.a. “Silicon Valley”). To increase and assess accuracy, we used the triangulation of overlapping, independent data sources and the application of certainty level standards. The region has been subject to extensive urbanization, so we also evaluated the applicability of historical landscape reconstructions to the altered landscape. We found evidence for five major land cover types prior to significant Euro–American modification. Valley freshwater marsh, wet meadow, alkali meadow, willow grove, and valley oak savanna have all experienced extreme decline (85–100%) since Euro–American settlement. However, comparison of historical land cover patterns to contemporary land use suggested several new strategies for environmental recovery, despite the limitations of surrounding urbanization. We also observed a temporal shift in riparian habitat along the mainstem of Coyote Creek, from a relatively open mixture of riparian scrub, sycamore woodland, and unvegetated gravel bars to dense riparian forest, likely resulting from stream flow regulation. By identifying former land cover patterns we provide a basis for evaluating local landscape change and setting restoration targets, including the identification of residual features and under-recognized land cover types. These findings suggest that reliable historical landscape reconstructions can be developed in the absence of standardized historical data sources and can be of value even in highly modified regions.  相似文献   
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Activities of acidic proteases (cathepsin B + L) and neutral, calcium-dependent proteases (CDP) were quantified to determine whether differences in proteolytic activity could explain differences in meat tenderness among breed types. Steers (n = 32) of known percentage Angus (A) and Brahman (B) breeding were used to establish differences in meat tenderness (A; 3/4A-1/4B; 1/2A-1/2B; 1/4A-3/4B). Samples were removed from the longissimus muscle within 1 h postmortem and within 2 h were frozen for subsequent determination of cathepsin B + L, CDP-I, CDP-II and CDP-inhibitor activities. Warner-Bratzler shear (WBS) was assessed after 1, 5 and 10 d of postmortem aging. Taste panel evaluations, conducted on steaks that were subjected to 5 d of aging, detected no differences. At d 1, WBS did not differ among breed types; however, by d 10 of aging, steaks from Angus steers were more tender (P less than .05) than steaks from 1/2B and 3/4B steers. The Angus and 1/4B steaks had significantly more (P less than .05) cathepsin B + L activity than the 3/4B. The CDP had no relationship with WBS; however, CDP-inhibitor was positively related to d-1 WBS (r = .41, P less than .05). Cathepsin B + L activity was negatively related to WBS at d 10 (r = -.44, P less than .05). These data suggest that differences in meat tenderness among breed types may be explained partially by differences in proteolytic enzyme activity.  相似文献   
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This report describes the clinical presentation, diagnosis, histological lesions, and prognosis of a primary choroidal malignant melanoma in a 15‐year‐old cat. The animal was presented for unilateral blindness. On ocular examination, a raised pigmented mass protruding from the posterior pole into the vitreous body was observed by diffuse transillumination and indirect ophthalmoscopy. Ocular ultrasound and computer tomography (CT) scan confirmed localization of the tumor to the posterior segment. The diagnosis of primary choroidal melanoma was confirmed by histopathology after enucleation. To our knowledge, this is the first reported case of a feline malignant melanoma with a primary choroidal localization without iris involvement.  相似文献   
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  1. Mediterranean fin whales aggregating in the Pelagos Sanctuary in summer to feed are exposed to vessel collision risk, particularly from high-speed ferries.
  2. This study developed models to predict summer fin whale distribution using a generalized additive model (GAM) and MaxEnt, with the aim of providing a tool to identify potential high whale–ferry collision risk areas along ferry routes within the Pelagos Sanctuary during summertime.
  3. Models were trained using sightings data collected in the summer months of 2009–2018 on board ferries crossing the central area of the Pelagos Sanctuary. Environmental predictors were bathymetry and mean sea surface chlorophyll concentration of the annual spring bloom period.
  4. The predictive ability of GAM and MaxEnt was assessed using existing knowledge of summer fin whale distribution in the region. GAM (deviance explained = 20.2%) predictions matched documented distributions more closely than that of MaxEnt, with highest predicted fin whale occurrence in deep offshore waters (>2000 m) encompassing the central north-western and western regions, and in the south-eastern region, consistent with known fin whale habitats within the Pelagos Sanctuary. Inter-annual variability was evident, influencing collision risk areas.
  5. Collision risk was estimated as a function of the overlap between the predicted probability of fin whale occurrence and ferry density estimated from Automated Identification System data. Ferry routes that cross the northern and eastern regions of the Pelagos Sanctuary presented relatively higher collision risk.
  6. Areas with changes in risk intensity between the years were temporally and spatially dynamic: some appeared intermittently throughout the study period while others persisted over consecutive years or recurred in different years.
  7. Due to the vastness of the Pelagos Sanctuary, vessel speed reduction maybe a more practical measure to manage collision risk than re-routing shipping lanes. A combination of Seasonal Management Areas and Dynamic Management Areas approaches could be adopted for high-risk areas.
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9.
Johne's disease (JD) is a costly intestinal disease of ruminants caused by Mycobacterium avium subspecies paratuberculosis (Map), which is transmitted to perinatal calves by the fecal-oral route. Disease control efforts focus on identification and culling of infected cattle from herds; therefore failure to identify animals early is a major obstacle to reducing transmission. Development of host immunity during early JD remain incompletely characterized so detecting subclinical JD using immunologic techniques is a substantial challenge in the field. Development of a test with high sensitivity and specificity is a major research goal with significant implications for the cattle industry. The objectives of this study were to compare early Map-specific T lymphocyte responses in naive, experimentally Map infected and Map vaccinated calves using a subcutaneous matrigel biopolymer-based assay. We examined the phenotype of recruited lymphocytes and local interferon gamma (IFNγ) production within subcutaneously placed matrigel containing Map antigen 30 days after experimentally induced intestinal Map infection or Map vaccination. We show that IFNγ-secreting CD4+ T cells are recruited to matrigel sites in vaccinated but not infected or naïve calves. γδ T cells recruited to matrigel sites of Map-infected calves were mostly WC1-, while γδ T cells recruited to matrigel sites of Map-vaccinated calves were predominantly WC1+. IFNγ at matrigel sites was a discriminating factor between infected calves, naïve calves and vaccinated calves. These data contribute to our understanding of early anti-Map immunity, and may be useful for detecting early intestinal Map infections in calves or for enhancing our ability to discriminate between Map-infected and Map-vaccinated calves.  相似文献   
10.
Abstract: Consensus is a term widely used in Sāmoa and elsewhere in the Pacific. It is considered to be a key feature of decision‐making and a fundamental characteristic of fa’asāmoa and other Pacific ways of being and doing. In Sāmoa it has been a mark of the strength and continuity of the fa’a matai through the ages of colonialism, neo‐colonialism and globalisation. However, although it has evolved in many ways to take into account new social trends (for instance allowing children to take part in family discussions) and remains strong at the family and village level, its role at the national level has virtually disappeared. This is seldom stated publicly and consensus is still held up as a defining characteristic of Sāmoaness. At the same time, although the rise of dissent is given little acknowledgement, it permeates public life. One could assume, based on this result that the ideology of consensus is perpetuated in order to reduce national public debate on governance issues.  相似文献   
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