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101.
102.
Arsenic (As) and antimony (Sb) are metalloids that belong to group 15 of the periodic table and exhibit toxic properties in the environment. They mostly occur naturally at low concentrations in soil, although these can be significantly elevated in both aquatic and terrestrial food chains as a result of dispersion from anthropogenic sources, e.g., mining activities. The bioavailability, i.e., the proportion of the contaminant in soil and dust that is available for uptake by plants and other living organisms, presents the greatest risk to terrestrial ecosystems. Various in vivo and in vitro methods have been used to measure As and Sb bioaccessibility in soil and dust. In vivo measurement of bioavailability can be time consuming, expensive, and unethical; thus, in vitro methods are commonly preferred. However, there is considerable uncertainty around the efficacy of in vitro tools used to measure the bioavailable fractions of As and Sb. The results of these methods are dependent on many variables, e.g., soil characteristics, contaminant sources, and chemical composition of in vitro methods. Therefore, substantial variations are observed between in vitro and in vivo results obtained from different test animals and endpoints. In this paper, we review the literature on As and Sb bioavailability in terrestrial ecosystems and current in vivo and in vitro techniques used for assessing bioavailability and bioaccessibility of metalloids. This would reveal research gaps and allow scientists and environmental policy makers to gain a deeper understanding of the potential risks associated with these metalloids in the environment. 相似文献
103.
Lessons on broodstock maintenance,spawning, larval rearing and juvenile production of marine gastropods of ornamental value 下载免费PDF全文
Iyadurai Jagadis Mookaiah Kavitha Jaganathan Padmanathan Ashok Maharshi Arumugam Varadarajakumar 《Aquaculture Research》2017,48(5):2581-2592
Research on marine gastropod breeding in India is in its infancy and scanty literature is only available. To fill the lacunae, marine gastropods of three ornamentally valued and conservation important groups such as Cyprids, Strombids and Muricids were held under captivity and studied for their broodstock maintenance, spawning behaviour, larval rearing and metamorphosis into juveniles at the Shellfish Hatchery of Central Marine Fisheries Research Institute, Tuticorin. Valuable information on the focal themes of the article was obtained for Strombids and Muricids leading to the successful life cycle closing for Lambis lambis and Chicoreus virgineus are reported earlier. In the present study, experiments were conducted on aspects such as post‐metamorphosed juvenile rearing up to 76 days post hatch for L. lambis, spawning, larval development and life cycle closing and reasonable level of juvenile production (8.8%) for Chicoreus ramosus. In addition, the primary observations on the captive breeding of Cypraea tigris with reference to its egg mass, brooding habit and early development is reported. However, while studying these groups few unanswered questions and bottle necks in their breeding nature, larval rearing and metamorphosis arose. The following account details the experiments conducted and results obtained in each of the focal themes of the paper and the constraints faced. 相似文献
104.
Ravi Kumar Rajesh Chandra S. K. Shukla D. K. Agrawal Mahesh Kumar 《Tropical animal health and production》1997,29(3):158-164
Summary Hydropericardium syndrome (HPS) in broiler birds of 3 to 6 weeks of age was recorded for the first time in the Haldwani area
of Nainital district (UP) in India in November, 1994. The overall mortality in 6 poultry farms was 61·62 per cent. The disease
was experimentally transmitted by bacteria free infected liver homogenate extract passed through membrane filters of 0·22
and 0·1 μ APD. The aetiological agent was inactivated by heat treatment at 56°C for one hour and 80°C for 10 min. A precipitin
band was demonstrated in agar gel immunodiffusion and counter immunoelectrophoresis using infected liver homogenate extract
as antigen and homologous antisera raised in the laboratory. The disease was effectively controlled by formalinised and heat
inactivated autogenous vaccine prepared from the infected livers of birds which died of natural infection.
Sindrome De Hidropericardio (HPS) En La India: Estudio Preliminar Acerca Del Agente Etiologico Y Del Control De La Enfermedad Mediante Vacunas Inactivadas Autogenas
Resumen Se describe por primera vez el síndrome de hidropericardio en pollos broiler de 3 a 6 semanas de edad en el area de Haldwani, en el distrito de Nainital (U. P.), en la India, en noviembre de 1994. La mortalidad global en seis granjas avícolas fue del 61·62%. La enfermedad fue transmitida de forma experimental mediante muestras homogeneizadas de hígado libres de bacterias y filtradas a través de filtros de membrana de 0·22 y 0·1 u APD. El agente etiológico fue inactivado por calor a 56°C durante 1 hora y 80°C durante 10 minutos. Se demonstró una banda de precipitina en inmunodifusión en agar gel y contrainmunoelectroforesis utilizando como antígeno extracto homogeneizado de hígado procedente de animales infectados y antisuero homólogo obrenido en el laboratorio. La enfermedad se controló de forma efectiva utilizando una vacuna autógena inactivada por calor y formol; la vacuna fue obtenida a partir del hígado de aves que murieron de infección natural.
Syndrome D’Hydropericardie En Inde: Etude Preliminaire Sur L’Agent Responsable Et Controle De La Maladie Par Un Vaccin Autogene Inactive
Résumé Le syndrome d’hydropéricardie (SHP) fut observé pour la premiere fois en Novembre 1994 chez des poulets de 3 á 6 semaines dans la région de Haldivani du district de Nainital en Inde. Parmi 6 élevages la mortalité fut de 61.62%. La maladie fut transmise expérimentalement en utilisant des extraits de foie infecté sans bactéries, homogénéisés et filtrés sur des membranes de 0,22 et 0,1 μm. L’agent pathogéne fut inactivés par traitement thermique à 56°C pendant une heure et à 80°C pendant 10 minutes. Une bande de précipité fut observée dans les gels d’agarose d’immunoprécipitation par immunoélectrophorèse utilisant des extraits de foie homogénéises en tant qu’antigène et des antisera homologues produits dans le laboratoire. La maladie fut restrainte de fa?on effective en utilisant un vaccin autogène, inactivé par la chaleur et traité par la formaline issude foies d’oiseaux infectés qui moururent d’infection naturelle.相似文献
105.
Gowrishankar S. Aravind M. Latha Bhaskaran Ravi Sreekumar C. 《Tropical animal health and production》2019,51(3):519-522
Tropical Animal Health and Production - Fifteen apparently healthy Kandari cross-bred cattle aged about 4 years were purchased from Rurki, Patiala district of Punjab by a private dairy... 相似文献
106.
Kharayat Nitish Singh Sharma G Chethan Kumar Gandham Ravi Bisht Deepika Chaudhary Gangaram Singh Sanjay Kumar Das Gautum Kumar Garg Anil Kumar Kumar Harendra Krishnaswamy Narayanan 《Veterinary research communications》2019,43(4):261-269
Veterinary Research Communications - Toll like receptors (TLRs) and β-defensins expressed in the endometrium are part of the innate uterine defense mechanism (UDM). In the present study,... 相似文献
107.
Muhammad Aslam M. K Arumugam Kumaresan Savita Yadav Tushar K. Mohanty Tirtha K. Datta 《Reproduction in domestic animals》2019,54(5):786-794
The present study identified few potential proteins in the spermatozoa of buffalo bulls that can be used as an aid in fertility determination through comparative proteomics. The sperm proteome of high‐fertile buffalo bulls was compared with that of low‐fertile buffalo bulls using two‐dimensional difference gel electrophoresis (2D‐DIGE), and the differentially expressed proteins were identified through mass spectrometric method. The protein interaction network and the functional bioinformatics analysis of differentially expressed proteins were also carried out. In the spermatozoa of high‐fertile bulls, 10 proteins were found overexpressed and 15 proteins were underexpressed at the level of twofold or more (p ≤ 0.05). The proteins overexpressed in high‐fertile spermatozoa were PDZD8, GTF2F2, ZNF397, KIZ, LOH12CR1, ACRBP, PRSS37, CYP11B2, F13A1 and SPO11, whereas those overexpressed in low‐fertile spermatozoa were MT1A, ATP5F1, CS, TCRB, PRODH2, HARS, IDH3A, SRPK3, Uncharacterized protein C9orf9 homolog isoform X4, TUBB2B, GPR4, PMP2, CTSL1, TPPP2 and EGFL6. The differential expression ranged from 2.0‐ to 6.1‐fold between the two groups, where CYP11B2 was high abundant in high‐fertile spermatozoa and MT1A was highly abundant in low‐fertile spermatozoa. Most of the proteins overexpressed in low‐fertile spermatozoa were related to energy metabolism and capacitation factors, pointing out the possible role of pre‐mature capacitation and cryo‐damages in reducing the fertility of cryopreserved buffalo spermatozoa. 相似文献
108.
109.
The study was investigated at Agricultural Experimental Farm, Giridih, India during winter seasons of 2007–2008 and 2008–2009. Plants grown with 100% recommended dose of fertilizer (RDF) [nitrogen (N): phosphorus pentoxide (P2O5): potassium oxide (K2O) = 150:60:60 kg ha?1] + AM + Azospirillum (T15) produced maximum chlorophyll, baby cob, and green fodder yield. Root biomass was highest with application of 150% RDF + arbuscular mycorrhizae (AM) + Azospirillum (T16). Co-inoculated plants produced higher chlorophyll, root biomass resulted higher cob and green fodder yield. Biofertilizers supplied along with chemical fertilizers saved 70, 29, and 33 kg N, P2O5 and K2O per hectare, respectively. Nutrient (NPK) uptake was greatest in T15. Residual soil fertility in terms of NPK was recorded maximum in T16. Although, co-inoculated plots built up higher residual soil fertility as compare to sole inoculation. Nutrients use efficiency and benefit cost ratio were higher due to application of 50% RDF with co-inoculants. T16 was most costly whereas T14 (50% RDF + AM + Azospirillum) was most beneficial. 相似文献
110.
Veera Karkamo Anu Kaistinen Anu N?reaho Kati Dillard Katri Vainio-Siukola Gabriele Vidgrén Niina Tuoresm?ki Marjukka Anttila 《Acta veterinaria Scandinavica》2014,56(1)