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31.
Experimental obliteration of high-contrast wing stripes of the neotropical butterfly Anartia fatima affected neither survival nor wing damage in a natural population over a 5-month period. There is no direct evidence supporting the hypothesis that so-called disruptive wing patterns function as protective coloration in butterflies.  相似文献   
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The majority of smallholder farming households in Cambodia are rurally based and rely on agriculture to support their livelihoods. However, in recent years, growth in the agriculture sector has stagnated with farmers facing several challenges including declining prices for traditional crops and irregular rainfall patterns. This has led to a need for farmers to diversify income sources with livestock promoted as a more viable livelihood activity, particularly the raising of cattle and poultry. However, uncertain profitability of livestock activities is a common perception by smallholders, especially where animals have not been traditionally viewed as a primary income source. To address this, information is required which compares the income and expenses associated with livestock raising to other on-farm activities and off-farm sources. This study reports on a survey of livelihood survey of 17 male and 21 female representatives of 20 households owning cattle in Cambodia, comparing the associated income and expenses of the various livelihood activities in the 12-month period from January to December 2016. Combined total household income from both on-farm and off-farm sources ranged from USD875 to 17730 with an average of USD6779, representing 51% and 49% from on-farm and off-farm activities, respectively. Cattle raising was the most common source of on-farm income (85%), contributing USD1064 and representing 22% of total household income. General household expenses, such as food and transportation (including expenses associated with off-farm employment), represented the majority of total household expenses (79%). Gross profit calculations indicated higher values for pig raising (USD1841.79), cattle (USD950.80) and non-rice crops (USD884) whilst the highest gross margin value was recorded for cattle (89.33%) followed by vegetables (85.27%) and non-rice crops (83.08%). Whilst wet season and dry season rice returned a negative gross profit value of USD197.27 and USD90.60 on average per household, respectively, both were ranked as most important for household consumption, followed by poultry, providing the main source of energy (rice) and protein (chicken meat) and sustaining household food requirements. The study concludes that although smallholder cattle-owning households in Cambodia undertake a diverse range of on-farm activities, as cattle raising provides a superior income source due to higher returns and lower variable costs, it could be promoted as a preferred livelihood activity by agencies conducting rural extension activities. Although consideration of available labour and monetary funds to invest in cattle raising is required, it was observed that income from off-farm sources may prove beneficial in providing the additional monetary funds to support cattle-raising activities and assist in providing generally poor smallholder households with enhanced economic resilience.  相似文献   
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A nasal mass in a Domestic Shorthair cat was causing facial deformity, sneezing and intermittent epistaxis. Biopsy samples obtained previously had been non-diagnostic. Computed tomography images revealed an irregular, contrast-enhancing mass occupying a large portion of the righthand side of the nasal cavity. Previously described criteria for malignancy were not present. A ventral surgical approach combined with temporary, ipsilateral, common carotid arterial occlusion provided excellent access for debulking the lesion and collecting samples for histopathology. A nasal vascular hamartoma was diagnosed and clinical signs resolved postoperatively. This is the first documentation of this abnormality in the cat. Hamartomatous abnormalities should be included on the list of differential diagnoses for feline nasal mass lesions. The prognosis for hamartomatous lesions postoperatively is good, in keeping with their limited propensity for growth after maturity.  相似文献   
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Congenital chondrodystrophy of unknown origin (CCUO), often referred to as 'acorn calf disease' or congenital joint laxity and dwarfism (CJLD), has been reported in beef cattle in Canada, the United States, Europe, South Africa, New Zealand and Australia. An association of CCUO with grazing drought-affected pastures, feeding hay-only or silage-only diets or supplementation with apple pulp suggests a nutritional cause such as a mineral deficiency. This review compares published reports on CCUO in order to identify common features among outbreaks and to provide a basis for future research into the condition. A protocol for investigation of outbreaks is provided to improve the outcome of future comparisons.  相似文献   
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