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121.
Nutrient budget for shrimp (Penaeus monodon) culture was performed in ten culture ponds (0.4–1.0 ha) in Orissa, India, at stocking density of 10.0–22.10/m2. The average initial body weight of shrimps was 0.02 g. The culture period was for 4 months. Feed was the main input of nitrogen (N), phosphorus (P) and organic carbon (OC). The FCR varied from 1.35 to 1.75. At harvest time, the average weight of shrimps varied from 28 to 32 g. Total N, P and OC applied to these ponds through all the inputs ranged from 106.64 to 292.63, 23.17 to 57.55 kg and 763.10 to 1,831.20 kg per crop, respectively. Feed alone accounted for 94.43–95.03 % total N, 91.92–95.36 % total P and 80.33–92.48 % total OC, respectively. The harvest of shrimp accounted for recovery of 25.45–36.88 (av. 30.12) %, 10.07–12.94 (av. 11.16) % and 15.80–20.81 (av. 18.01) % of added N, P and OC, respectively. N, P and OC accumulated in sediment were 49.11, 64.07 and 64.82 %, respectively, of total nutrient retention in the culture system. Unaccounted N, P and OC were 13.29, 21.83 and 18.14 %, respectively, of the total nutrient retention in the system. N, P and OC outputs in the discharged water during harvest were 7.48, 2.94 and 2.03 %, respectively. 相似文献
122.
Australian bat lyssavirus (ABLV) is a member of the Lyssavirus genus of the Rhabdoviridae family and is found in Australian bat species. It is of public health concern because of the rabies-like syndrome it causes in humans, resulting in government health and wildlife agencies using varied communication approaches to inform targeted audiences about zoonotic risks associated with handling bats. Despite these warnings, the number of reports of human-bat interactions remains high. This paper details a survey conducted to analyse the approaches utilised by a range of stakeholders to educate and communicate warnings to their target audiences. The survey focused on identifying the target audiences, communication methods used, along with the message frequency, content, and perceived effectiveness. Analysis of the top three messages delivered by stakeholders revealed that over half were information-focused messages and over a third, instruction-focused. Stakeholders identified the need to balance messaging about bat handling risks with information regarding the vulnerable status of bats and their environmental significance. Whilst the most common and (perceived) effective method of communication was one-on-one discussions, it was also identified to be ineffective for targeting mass audiences leading stakeholders to recognise the need to adapt to more efficient means of communication. The outcomes of this study may be useful to improve risk communication strategies regarding ABLV in Australia. 相似文献
123.
Subhasis Dey Sunil Kumar Choudhary Sushant Dey Kadambari Deshpande Nachiket Kelkar 《Fisheries Management and Ecology》2020,27(2):140-154
Local ecological knowledge (LEK) can offer insights into fisheries management by describing long‐term changes that are difficult to unravel in data‐poor river‐floodplain fisheries. LEK is derived from complex interactions between fishers’ observations of environmental change and their institutional capacities to manage fisheries. Hence, it is important to understand where and how LEK and formal scientific studies on fish species’ decline could complement each other. In this paper, the causes of decline of 58 fish and two shrimp taxa were identified from LEK data (1999–2019) obtained from river–floodplain fisheries of the Gangetic plains (Bihar, India). Qualitative analyses of LEK were used to generate species‐specific hypotheses and historical insights on their declines. Destructive fishing, overfishing and the Farakka barrage were cited by fishers as the major causes of declines. Potential reasons for these perceptions were explored in relation to fishers’ experiences of conflicts in the region over fishing rights and access. 相似文献
124.
A velogenic Newcastle disease virus isolate typed to belong to group C1 by monoclonal antibody typing was adapted 50 times
in chicken embryo fibroblast cell culture and 60 times in Vero cells. At every 10th passage the virus was characterized on
the basis of mean death time, intracerebral pathogenicity indices and viral titration studies. A gradual reduction in the
virulence of the virus was noted as the passage number increased. RT-PCR of a 254 bp region of the fusion gene encompassing
the fusion protein cleavage site was carried out for the virulent as well as cell culture-adapted viruses at every 10th passage
level. The amplicons were subsequently digested with three restriction enzymes, viz. AluI, HaeIII and PstI. It was found out that there was difference in banding patterns between the virulent and adapted viruses, indicating nucleotide
substitutions in the virulent virus when it was sequentially passaged onto cell culture systems. 相似文献
125.
John M. Kabrick Daniel C. Dey J. W. Van Sambeek Mark V. Coggeshall Douglass F. Jacobs 《New Forests》2012,43(5-6):695-710
Growing interest worldwide in bottomland hardwood restoration necessitates improved ecological understanding of flooding effects on forest tree seedlings using methodology that accurately reflects field conditions. We examined hardwood seedling survival and growth in an outdoor laboratory where the timing, depth, duration, and flow rate of flood water can be carefully controlled while simulating natural soil conditions occurring in floodplains. Flooding treatments were initiated in mid-May and included partial inundation (15–20?cm) during the growing season for 5-week flowing, 5-week standing, 3-week flowing, and control. We monitored the vigor, survival, and growth (changes in basal diameter and stem length) of six hardwood species representing a wide range in expected flood tolerance including eastern cottonwood (Populus deltoides Bartr. Ex Marsh.), pin oak (Quercus palustris Muenchh.), swamp white oak (Q. bicolor Willd.), bur oak (Q. macrocarpa Michx.), black walnut (Juglans nigra L.), and pecan [Carya illinoensis (Wangenh.) K. Koch]. All stock was 1-0 bareroot except that cuttings were used for eastern cottonwood. Five species—eastern cottonwood, bur oak, swamp white oak, pin oak, and pecan—exhibited high survival probabilities (>0.62 for cottonwood; >0.77 for the others) regardless of flood treatment. But of the survivors, only eastern cottonwood and swamp white oak maintained positive growth and healthy green foliage. Despite high survival, bur oak and pin oak suffered stem growth losses and exhibited chlorotic foliage in flood treatments suggesting greater vulnerability to other abiotic or biotic stresses if outplanted on flood-prone sites. Pecan also suffered stem dieback in controls suggesting vulnerability to competition and browsing when outplanted despite high survival after flooding. Our quantitative data helps to confirm and/or refine previously published qualitative flood tolerance ratings for these species, and describes operation of an in situ outdoor flood experiment laboratory that may prove effective in guiding future flood tolerance research. 相似文献
126.
Impact of the Community‐based Fish Culture System on Expenditure and Inequality: Evidence from Bangladesh
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A. B. M. Mahfuzul Haque Madan Mohan Dey 《Journal of the World Aquaculture Society》2016,47(5):646-657
This study investigated the impact of a Community‐based Fish Culture (CBFC) system on household expenditure and how expenditure inequality in the fish‐producing communities has changed due to involvement in the CBFC system. Six floodplains, comprising three project sites and three controls, were chosen from three river basin areas of Bangladesh; data for this study were collected for a period of 3 yr. A propensity score matching method was used to evaluate the impact of CBFC on household expenditure; while a Gini coefficient and Gini decomposition were used to estimate inequality. The results show that the CBFC system has a positive and significant impact on fish culture community household expenditure. Results also reveal that the CBFC system has an equalization effect on food, clothing, and healthcare expenditure. Furthermore, this management system helps to distribute total expenditure 15% more equally among the fish culture communities. 相似文献
127.
Ghosh Arkendu Dey Koyel Hassan Md. Abu Bauri Fatik Kumar Das Bikash Chandra Bhowmick Nilesh Dey Amarendra Nath Das Soumitra Sahu Pradip Kumar 《Genetic Resources and Crop Evolution》2022,69(7):2585-2604
Genetic Resources and Crop Evolution - Semecarpus anacardium L. is a potential underutilized edible, highly nutritious fruit crop with ample medicinal properties grown in some localized pockets of... 相似文献
128.
The effects of lactation on the fertility of dairy cows 总被引:1,自引:0,他引:1
Lactation has been negatively associated with fertility because pregnancy rates in maiden heifers exceed those obtained after first or subsequent calvings. The extent of this difference is less in pasture-fed dairy cows (<10%) than in American Holsteins (>20%) fed grain and conserved forages. The latter cows have pregnancy rates to first insemination and oestrus detection rates of only 40 to 45%. This suggests that the subsequent fertility of inherently fertile Holstein heifers may be severely compromised by high levels of milk production. International comparisons show that pasture-fed dairy cows may experience extended periods of anovulatory anoestrum but have normal fertility (60% pregnancy rate to first insemination) once cycling. The high-producing American Holstein may ovulate within 4 weeks postpartum but is more likely to continue ovulating without being detected in oestrus. Both situations are associated with negative energy balances (NEB) during early lactation. The severity and duration of this NEB may vary with body condition at calving, age or parity, ration formulation, production level and environmental factors. Relative daily milk yield is not an absolute indicator of NEB, because some lower producing cows within a herd have lower feed intakes and more severe energy deficits. NEB is not simple to measure; nonetheless, it is correlated with genetic improvement for milk yield. A positive energy balance, greater weight gain and higher body condition score have all been shown to be positively correlated with plasma progesterone concentrations in early lactation. No studies have investigated the possibility that the rapid increase in metabolic rate at this time may also alter steroid concentrations with consequent effects on oestrous behaviour and fertility. Studies to more precisely define the effects of increasing milk yields in early lactation, especially in Holsteins, may need to be completed in Australia and New Zealand. Oestrus detection rates and pregnancy rates for American Holsteins of less than 50% are accepted widely in the USA. Such low detection rates confound studies on fertility. The objective should be to increase these 2 rates to at least 80% and 60% respectively. This may involve the use of controlled breeding, especially if oestrous behaviour is less overt in high-producing Holstein cows. 相似文献
129.
NJ Kannegieter KL Schaaf DK Lovell CD Simon BM Stone 《Australian veterinary journal》2010,88(4):132-136
We describe a fibrosarcoma in a 12-year-old Quarterhorse × Arabian gelding as a sequela to equine influenza vaccination. Shortly after the second vaccination, swelling at the site was noticed by the owner and it continued to increase in size over the following 6 months. Biopsy of the mass indicated a fibrosarcoma had developed at the vaccination site. It was approximately 20 cm in diameter and elevated well above the level of the skin. There was no clinical evidence of metastases to the lungs or local lymph nodes. Surgical resection of the mass was performed and the wound healed by first and second intention. Histopathological examination and immunohistochemical staining confirmed a myofibroblastic fibrosarcoma with multifocal osseous metaplasia. To the authors' knowledge, this is the first equine case of a vaccine-associated fibrosarcoma. 相似文献
130.
ML Lepherd PJ Canfield GB Hunt PC Thomson KL Bosward 《Australian veterinary journal》2011,89(7):238-238