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521.
The remnant of ultimobranchial (UB) body in the thyroid gland of adult buffalo was studied. This remnant appeared in the form of irregular and elongated follicles of various size and shape with folded lumen. These structures occupied a peripheral location beneath the capsule, as well as being embedded mostly in the vascular connective tissue of the thyroid. Calcitonin cells were predominantly localized in the UB follicles. Scanning electron microscopy revealed that surface of most UB follicular cells was almost flat and polyhedral or hexagonal in shape. Other follicles possessed cells with dome shaped apical surface demarcated by a shallow intercellular depression. The luminal surface of the follicular cell lining was studded with microvilli that appeared with various density and length and were numerous at the cellular borders. Interestingly, most of UB follicular cells were provided with single cilium, projecting over the cell surface. Notably some UB follicles presented various stages of apocrine activities.  相似文献   
522.
Peste des petits ruminants (PPR) is an economically important disease that affect sheep and goat industry in Asia and Africa. In this study, we investigated the seroprevalence, and risk factors, of PPR in sheep and goat flocks from five different governorates (Irbid, Jarash, Ajloun, Mafraq and Zarka) located in Northern Jordan. Serum samples from 929 and 400 sheep and goats, respectively, corresponding to 122 sheep flock and 60 goats flock were collected. Seroprevalence was determined using PPR competitive ELISA. Health status and management information were collected using a semi-structured pre-tested questionnaire. The individual true prevalence of PPR in sheep and goats was 29 and 49%, respectively. The flock level true prevalence of PPR was 60 and 74% in sheep and goats, respectively. In both sheep and goat flocks, large flock size, visiting live animals market and inadequate veterinary services were identified as risk factors for PPR seropositivity. Mixed (sheep and goats) raising was identified as a risk factor for PPR seropositivity in sheep flocks only.  相似文献   
523.
Freezing and prolonged frozen storage of dough results in constant deterioration in the overall quality of the final product. In this study the effect of wheat bran and wheat aleurone as sources of arabinoxylan (AX) on the quality of bread baked from yeasted frozen dough was investigated. Wheat fiber sources were milled to pass through a 0.5 mm screen, prehydrated for 15 min, and incorporated into refined wheat flour at 15% replacement level. Dough products were prepared from refined flour (control A), whole wheat flour (control B), aleurone composite flour (composite flour A), and bran composite flour (composite flour B) and stored at –18°C for 28 weeks. Dough samples were evaluated for breadmaking quality at zero time, 14 weeks, and 28 weeks of storage. Quality parameters evaluated were loaf weight, loaf specific volume, and crumb firmness. Composite flour bread samples showed the most resistance to freeze damage (less reduction in the overall product quality), indicating a possible role of some fiber components (e.g., AX) in minimizing water redistribution in the dough system and therefore lessening adverse modifications to the gluten structure. The data suggest that the shelf life of frozen dough and quality of obtained bread can be improved with the addition of an AX source.  相似文献   
524.
We assess potential future impacts of climate change on wheat yields in Swat and Chitral districts of Pakistan, mountainous areas with average altitudes of 960 and 1500 m above sea level, respectively. Using past climate data (1976–2000) to track temperature trends in both study districts, we find that increased temperatures correspond to an increase in Growing Degree Days (GDDs) and a decrease in Growing Season Length (GSL). Chitral district shows a stronger decline in season length than Swat district. Compared with the estimated optimum level of 157 days, the 25 year average GSL for the dominant varieties is estimated to be 156 days in Swat district and 195 days in Chitral district. Future increases in temperature of 1.5 and 3 °C are likely to cause wheat yields to decline (by 7% and 24% respectively) in Swat district and increase (by 14% and 23% respectively) in Chitral district. Future increases in precipitation of 5–15% during the growing season show a negligible impact on wheat yield.  相似文献   
525.
  1. The Eurasian otter (Lutra lutra), smooth‐coated otter (Lutrogale perspicillata), and Asian small‐clawed otter (Aonyx cinereus) have all been reported previously from the Indian state of Uttarakhand. However, little information is available about their current distribution in a mountainous region that is subject to increasing human‐induced stressors (such as hydropower plants, pollution, sand and boulder mining, destructive fishing techniques, poaching).
  2. Owing to important roles played by these otters in structuring riverine food webs (particularly taking account of their roles as top carnivores), it is critical that they receive suitable protection in the face of projected temperature rise, change in precipitation patterns, and associated river flows in this Himalayan biodiversity hotspot. This study assesses otter distribution in four rivers of Uttarakhand as a basis for informing future conservation actions.
  3. Field surveys were conducted (October 2018–January 2019) in reaches of the Kosi, Ramganga, Khoh, and Song rivers, supported by semi‐structured interviews (N = 379) conducted with members of local communities to collect qualitative data on views and perceptions of otter species. In addition, community‐based otter awareness camps were organized for local youths (N = 105), adults (N = 115), and schoolchildren (N = 256 covering 10 schools).
  4. Habitat suitability maps were created using remote‐sensing data, survey findings, and a geographic information system to provide information about priority reaches of river to be targeted for future conservation efforts.
  5. This study provides critical interdisciplinary baseline information to guide decision‐makers towards developing a targeted, otter‐specific conservation programme for this important Himalayan biodiversity hotspot.
  6. The otter conservation education programmes conducted during this study resulted in a proposal to set up a community‐based conservation initiative to monitor and report otter sightings from the area, potentially representing a way forward for achieving simultaneous otter conservation and associated ecosystem benefits for local communities.
  相似文献   
526.
The UN Law of the Sea Convention (LOSC) and one of the implementing agreements of the Convention—the UN Fish Stocks Agreement (UNFSA)—mandates all states to cooperate in the management of highly migratory and straddling fish stocks. In doing so, the UNFSA specifies that the special requirements of developing states need to be taken into account. To date, except in the Western and Central Pacific Fisheries Commission (WCPFC), there is no formal mechanism to identify these differential responsibilities in tuna regional fisheries management organizations (RFMOs). Although some conservation and management measures exempt small-scale and artisanal fishing vessels, power imbalances within RFMOs tend to favour the interests of more developed and larger distant water fishing nations over those of small developing coastal states. To facilitate the implementation of differentiated responsibilities as mandated in UNFSA, in this study we develop a three-step framework that could be applied in the case of new conservation and management measure proposals. The framework has also been tested based on two developing countries and compared with a developed state in the Indian Ocean Tuna Commission and the adopted resolutions in 2019. To facilitate better transparency and equitable decision-making processes across RFMOs, this framework could be adapted based on member states' fisheries management objectives and target and non-target species.  相似文献   
527.
A passive surveillance study was conducted from April 2012 to April 2013 to determine the incidence, the affect of age, sex and cyst location, fertility, and viability on the occurrence of cystic hydatidosis in slaughtered goats from six municipal abattoirs around Oman. Morphologic characterization of suspected visceral organs has shown that Echinococcos granulosus (E. granulosus) metacestodes were present in 9.2 % of the total samples (682). Incidence (per 10,000) varied from 1.4 to 1.5. There was a significant difference between abattoirs, with Salalah having the highest infection (63.2 %), followed by Nizwa (27.2 %), Al Buraimi (10.8 %), Bousher (7.2 %), and the lowest in Sohar (1.6 %). Infection was significantly higher in indigenous goats (22.1 %) compared with imported breeds (2.5 %) from Somalia. The visceral organs were found harboring one or more hydatid cysts. Greatest cyst infection was recorded in lungs (53.4 %), followed by heart (50 %), liver (6.2 %), and multiple organs (14 %). A significant difference was observed between females (25 %) and male goats (6 %). Furthermore, the fertility of the hydatid cysts was found higher in heart and lungs (100 %, 51.6 %) and the viability rate of protoscolices was high (64 %). The findings of this study demonstrated that cystic hydatidosis is common and widely distributed in local goats, and they might play an important role in the life cycle and transmission of this zoonosis in Oman.  相似文献   
528.
Buffalo is an economically important dairy animal in South Asia but mostly ignored in research priorities. In this retrospective study, the effect of management practices and age of animal on the incidence of mastitis in Nili Ravi buffaloes was investigated. A total of 1,560 quarters of buffaloes (n?=?390) were screened by visual examination of the udder and milk (clinical mastitis) and California mastitis test (subclinical mastitis). Household data was collected on a predesigned questionnaire and analyzed. The prevalence of subclinical mastitis, clinical mastitis, and blind quarters was 41.8, 13.6, and 9.7 %, respectively. The highest prevalence was noted in the hind quarters and left side as compared to that in the forequarters and right side. This data significantly (p?p?p?R 2?=?0.772) with mastitis. This study concluded that some factors alone or in combination with other factors influence significantly the occurrence of mastitis, and to minimize the infection, these factors should be considered. The outcome of the study will be valuable for policy-making for positive management practices and implementation of preventive measures.  相似文献   
529.
Anthocyanins are important dietary components that play significant roles in human health because of their antioxidant and anti‐inflammatory properties. In the present study nine anthocyanin‐pigmented spring wheat lines grown at two sites in central Saskatchewan, Canada, were evaluated in terms of anthocyanin composition in comparison with four wheat checks over a two‐year period. The genotypes studied were blue‐aleurone and purple‐pericarp wheat. The anthocyanin pigments were quantified and identified with liquid chromatography and mass spectrometry. Two anthocyanin profiles were identified in the breeding lines, namely, blue profile and purple profile. Wheat lines with a purple profile had overall higher anthocyanin concentrations and more pigments than the blue‐aleurone lines. The purple profile was also characterized by the presence of acylated anthocyanins containing malonyl and succinyl substituents, but no acylated pigments were found in the blue profile. Delphinidin was the dominant aglycone in the blue profile, whereas cyanidin was the principal anthocyanidin in the purple profile. Genotype and interactions among genotype, year, and location were found to significantly influence content and composition of anthocyanin pigments. These differences in anthocyanin content and composition reflect various color characteristics and bioactivity for purple or blue wheat when utilized.  相似文献   
530.
The influence of soil constituents including sand, silt, clay, organic substances, aluminium and iron on crust development and seedling emergence was investigated in a selection of 30 soils. After treatment with simulated rain, soil crust strength as measured by penetration resistance to an upward-moving probe tended to decrease with increasing total organic carbon content, but the relationship was not a simple one. Consideration of other factors showed that in some soils (soils of 1.5–2% total organic carbon), alkali-exractable carbon and clay contents had the greatest influence on penetration resistance values whereas in other soils (2.4–3% total organic carbon), coarse sand, fine sand, EDTA-extractable aluminium and humic acid carbon were highly correlated with penetration resistance. In a group of soils with around 4% total organic carbon, oxalate-extractable aluminium appeared to exert a dominant influence. There was a good correlation between humic acid carbon and penetration resistance after rain treatment in soils containing less than 40% sand. A similar relationship was also noted with EDTA-extractable iron.Combination of all factors in a multiple regression analysis accounted for a considerable proportion of the variation in penetration resistance of soils with and without simulated rain application and in seedling emergence of barley. Organic carbon, and the humic acid fraction in particular, were most important in determining crust strength for all soils as a group.A significant correlation between plastic limit moisture and the logarithm of penetration resistance is explained partially, at least, by the relationships that exist between organic carbon alone, clay alone and a combination of both, with variation in moisture.  相似文献   
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