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51.
Jyoti R. Mohanty Sankar N. Das Harish C. Das Sarat K. Swain 《Fibers and Polymers》2014,15(5):1062-1070
Polyvinylpyrrolidone/date palm leaf fiber (PVP/DPL) biocomposites were prepared by melt mixing fabrication technique with different weight percentage of fibers. DPL fibers were chemically modified by acrylic acid in order to have better dispersion and compatibility with PVP matrix. The interaction of DPL fibers with PVP matrix was studied by Fourier transforms infrared spectroscopy (FTIR). Field emission scanning electron microscope (FESEM) was used for the study the morphology of chemically modified DPL fibers and PVP/DPL biocomposites. Mechanical properties were improved with fiber loading due to strong interfacial adhesion between PVP and DPL fibers. The storage modulus, loss modulus and tan delta values of PVA/DPL biocomposites were measured by DMTA. The rheological properties were investigated to study the shearing storage and loss modulii along with complex viscosity of biocomposites. The thermal and conducting properties of biocomposites were measured and compared with that of virgin PVP. 相似文献
52.
L. S. Gay D. S. Kronfeld PhD DSc MVSc A. Grimsley-Cook DVM MS J. J. Dascanio DVM A. O. Ordakowski-Burk PhD R. K. Splan PhD E. A. Dunnington PhD D. J. Sklan PhD 《Journal of Equine Veterinary Science》2004,24(3):115-120
Fat-soluble vitamins transfer poorly across the diffuse epitheliochorial placenta of the mare, so the neonatal foal is dependent on its supply via colostrum. Concentrations of retinol (RT), β-carotene (BC), and β-tocopherol (AT) were assayed in samples of plasma, colostrum and milk from nine mares of mixed light breeding and their foals at parturition and days 1, 2, and 4 postpartum. Samples were analyzed simultaneously for RT, BC, and AT using a new, less time-consuming reverse phase high-pressure liquid chromatography (HPLC) method. Feeds were analyzed, and mean daily intakes calculated. Mare plasma RT increased from day 1 to day 4 (P = .033), and plasma AT declined linearly from day 0 to day 4 (P = .006). Colostrum concentrations of all vitamins increased from parturition to day 1, and then declined rapidly over the 4 days. Foal plasma BC increased from parturition to day 4 (P = .080), and plasma AT increased from parturition to day 2 (P < .001), and 4 (P = .060). These observations suggest that three times the current recommendation of vitamin A is sufficient for pregnant mares, in keeping with previous studies of growth, pregnancy, and lactation. In contrast, the linear decrease in mare plasma AT suggests that 1.2 times the current recommendation of vitamin E may be less than optimal for pregnant mares.
Introduction
The diffuse epitheliochorial placenta of the mare does not allow fat-soluble vitamins to cross with ease to the fetus,[1] so their status in the neonatal foal is dependent on colostrum. This first milk contains these vitamins, which are necessary for many functions.Vitamin A is required for vision, reproduction, growth, development, and maintenance of epithelial cells, and osteoclast activity in bone formation. In addition, vitamin A deficiencies reduce resistance to disease, can cause neurological degeneration, and congenital defects.[2] Vitamin E, an antioxidant, prevents lipid peroxidation and cell membrane damage. Its deficiency in horses has been associated with a form of muscular dystrophy and impaired immune function. [3]Studies on the mare and foal have described blood concentrations of one or two of these vitamins,[4, 5 and 6] but only one involved all three. [7] In that study, vitamin concentrations were assayed in mare blood and milk, but only once in foal blood at parturition, so data during the periparturant period is incomplete.The objectives of this enumerative study were to determine concentrations of RT, BC, AT in plasma and colostrum, to evaluate colostral transfer of these vitamins, to assess the adequacy of vitamin intakes of mares, and to develop a time-saving single-run HPLC method.Materials and methods
Animals
Nine healthy aged multiparous mares of mixed light breeding (13.6 ± 1.5 years, 592 ± 20 kg body mass) and their foals were sampled. The institutional animal care and use committee approved the protocol. Mares were kept on meager late-winter mixed grass pasture, with free access to round bale orchard and fescue grass hay, water, and trace mineral/vitamin salt. They were fed 2 kg of concentrate twice daily at 7:00 and 3:00 . The diet met or exceeded current recommendations for pregnant mares at 11 months gestation for energy.[8] Samples of hay and concentrate were submitted for partial proximate analysis to the Virginia Tech Forage Testing Laboratory where standard AOAC [9] methods are used ( Table 1). Samples of feeds were also taken for analysis of RT, BC, and AT ( Table 2). 相似文献53.
Traumatic injuries of the penis result from kick-related injuries, and injuries during coitus or masturbation are reported as common causes of penile hematoma in horses. In the present report, mating for the first time in a 2-year-old colt resulted in penile hematoma. The animal had difficulty in passing urine and had paraphimosis. Under general anesthesia a stab was given to drain the hematoma, and hydrotherapy with cold water along with antibiotics and analgesics was advised. Early surgical intervention and drainage of the hematoma helped in resolving the condition and resulted in normal functioning of the penis. 相似文献
54.
Radiographic,computed tomographic,and arthroscopic diagnosis of radioulnar incongruence in dogs with medial coronoid disease 下载免费PDF全文
55.
Marjory B. Brooks DVM Robert E. Matus DVM MS Connie E. Leifer DVM. Alan A. Alfieri PhD Amiya K. Patnaik BVSc MVSc 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1988,2(4):206-211
The effect of adjuvant chemotherapy and combined chemotherapy and radiotherapy in 22 dogs with advanced canine tonsillar carcinoma (World Health Organization [WHO], T2-3 primary tumor with infiltration into surrounding tissues) was evaluated. There were four treatment groups of at least five dogs each. Combinations of chemotherapeutic drugs reported to have activity against squamous cell carcinoma in humans and dogs (doxorubicin, cisplatin, vinblastine, and cyclophosphamide) were administered after tonsillectomy. Radiation therapy (orthovoltage type, external beam) was combined with chemotherapy in one treatment group. The dogs that had combination radiation therapy and chemotherapy had higher response rates and significantly longer survival times. However, most dogs died of progression of disease. 相似文献
56.
Karanvir S. Aulakh BVSc & AH MS MS CCRP DACVS-SA Kaustubh R. Dongaonkar BVSc & AH MVSc Katherine Barnes DVM MS CCRP DACVS-SA Alberto J. Gines DVM DECVS Jude T. Bordelon DVM MS MBA DACVS-SA Don Hulse DVM DACVS DECVS Harmeet K. Aulakh BVSc & AH MVSc DACVIM Chin-Chi Liu MS MApStat PhD 《Veterinary surgery : VS》2020,49(3):455-462
57.
58.
A greenhouse experiment was conducted to evaluate the critical toxic limits of nickel (Ni) in french bean grown on a mollisol receiving varying levels of farmyard manure (FYM). Nickel levels beyond 10 mg kg?1 soil brought a significant reduction in the dry matter yields of french bean. Application of FYM, especially at the higher level (4.46 g kg?1 soil), had a favorable effect on the dry matter yields of french bean. The effect of FYM application was more pronounced at the medium levels of Ni. Application of higher level of FYM could decrease Ni concentration in plants significantly. Different soil extractants employed in the present study could be arranged in the following order of their Ni extraction power: Mehlich 3 > 0.1 N hydrochloric acid (HCl) > double acid > ammonium bicarbonate (AB)-diethylenetriaminepentaacetic acid (DTPA) > DTPA. Among different extractants evaluated in the study, DTPA (pH 7.3) appeared to be most promising for predicting Ni concentration in french bean. The threshold toxic levels of Ni in french bean and also in terms of extractable soil Ni contents were influenced by FYM application. 相似文献
59.
Ritu PANWAR Jyoti MATHUR 《土壤圈》2023,33(1):93-104
Polycyclic aromatic hydrocarbon(PAH) pollution is a global concern because of their toxicity to environment and ecosystem, which induces adverse effects on plants, animals, and humans. Hydrocarbons are mainly released from natural and anthropogenic activities, such as incomplete fuel combustion, leakages in oil pipelines, and the extensive use of pesticides; PAH contaminants include petroleum hydrocarbons(PHCs), halogenated hydrocarbons, chlorophenols, and pesticides. Bioremediation using microo... 相似文献
60.
Raktim Sarmah Sarada Kanta Bhagabati Rajdeep Dutta Dipanka Nath Hemanta Pokhrel Lawonu P. Mudoi Nishi Sarmah Jiten Sarma Abdul M. Ahmed Rupam Jyoti Nath Lucy Ingtipi Kedolhouse Kuotsu 《Aquaculture Research》2020,51(9):3839-3846
The synthetic antioxidant 3,5‐di‐tert‐butyl‐4‐hydroxytoluene (BHT) is widely used as an additive in the food, cosmetic and plastic industries to increase the tenability of food and plastic for the past 70 years. BHT is degraded to 3,5‐di‐test‐butyl‐4‐hydroxybenzaldehyde (BHT‐CHO) in mammals, as well as in the natural environment such as in river and water. The average daily intake of BHT for human being is estimated to be 0.3 mg/kg body weight. Even though it is considered safe for human at authorized level, but its ubiquitous presence in the aquatic environment and the controversial toxicological data are of great concern for human as well as aquatic life. The experimental findings of zebrafish embryo toxicity test (ZFET) showed that the acute toxicity of 96‐hr (LC50) exposure during the embryogenic stage was found to be 4.388 mg/L and the effective concentration (EC50) was 1.375 mg/L. The reduce heart rate from the sublethal concentrations indicates the chemical to be cardiotoxic but a further review is to be needed. The Teratogenic Index (TI) calculated to be 3.19, which implies the compound may be a potential teratogen in aquatic life. The findings obtained in this study will stretch more evidence regarding developmental toxicity of BHT, which will be of much importance in further risk assessment of ecotoxicological studies. 相似文献