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32.
Jamuna Valsalan Atish Kumar Chakravarty Chandrashekhar Santosh Patil Shakti Kant Dash Atul Chandrashekhar Mahajan Vijay Kumar Vikas Vohra 《Tropical animal health and production》2014,46(6):967-974
Selection for genetically superior Murrah buffaloes under Network Project on Buffalo Improvement, India, is presently based on milk yield, and it was observed that even in the absence of any direct selection pressure applied on fertility, there has been a downward trend in fertility associated with the selection for milk yield. The aim of the study was to develop selection indices which include fertility besides milk yield in Murrah buffaloes. Data pertaining to 1,224 lactation records spread over a period of 19 years were recorded and analyzed in the study. The negative association of pregnancy rate (fertility) with a 305-day milk yield (?0.08?±?0.04) and wet average (?0.12?±?0.02) indicated the importance of incorporating fertility trait in the construction of selection index. Four types of selection indices were constructed and evaluated. Two indices were developed using expected producing ability 305-days milk yield (EPAMY) with 6.5 and 4 % fat in milk along with expected fertilizing ability (EFA). The other two indices developed consist of expected producing ability wet average (EPA WA) and EFA. The index involving (EPA WA and EFA) was found to be a more effective selection criterion in our herd, as the accuracy of index was more (0.61), in comparison to the index involving EPA MY and EFA. The robustness of selection index was assessed by increasing the relative economic values of included traits by 25 and 50 %, and accuracy of the index remains almost stable without much change. The developed selection strategy involving EPA WA and EFA should be considered for the genetic evaluation of Murrah buffaloes, as it has a potential for maximizing the lifetime reproduction and production performances of the breed. 相似文献
33.
Rupali Mehta Vikas Sharma Anil Sood Madhu Sharma Ram Kumar Sharma 《European Journal of Forest Research》2011,130(5):729-736
Bambusa nutans Wall., is an evergreen, perennial, and multipurpose bamboo having strong culms, which are largely used for construction,
scaffolding, craft purposes, pulp, and paper industry. Multiple shoots from nodal segments (3–4 cm) of young branches of mature
culms were established in Murashige and Skoog (1962) (MS) medium supplemented with various concentrations of 6-benzylaminopurine (BAP) (1.0–6.0 mg l−1) or in combination with α-naphthaleneacetic acid (NAA) (0.5–1.0 mg l−1) or kinetin (Kn) (1.0–2.0 mg l−1). February–March and December were found to be the best seasons for culture establishments. Maximum shoots were achieved
on MS medium fortified with BAP (2.0 mg l−1). Embryogenic callus (slightly greenish compact, globular, and slow growing) was initiated from the base of severed sprouted
buds in 2–3 subsequent subcultures on MS medium supplemented with 2,4-dichlorophenoxy acetic acid (2,4-D) (5.0 mg l−1) under dark incubations. Maturation and germination of well-organized somatic embryos was achieved on MS medium containing
BAP and 2,4-D (1.0 mg l−1 each) with 20.0 mg l−1 ascorbic acid. Full-strength MS medium supplemented with 2% glucose favored further development of proliferated somatic embryos
into plantlets. Genetic variations of field-established B. nutans plants regenerated through tissue cultures were assessed by amplified fragment length polymorphism (AFLP) analysis using
6 primer combinations. Four hundred and seven scorable fragments were amplified, of which 402 (98.8%) have recorded conservation
at various morphogenetic stages leading to plantlets regeneration, therefore, revealed a high level of genetic stability. 相似文献
34.
Neelesh Sharma Tae Young Kang Sung-Jin Lee Jin Nam Kim Chang Hyun Hur Jong Chul Ha Vikas Vohra Dong Kee Jeong 《Tropical animal health and production》2013,45(8):1829-1832
The present investigation was carried out to study the prevalence of mastitis in 136 Holstein cows from a subtropical province of South Korea. Out of 527 milk samples studied, 22.6 % were found positive for mastitis. On animal level, prevalence was estimated at 55.2 %. Late lactating cows were at higher risk for mastitis development as compared to those in early and mid lactations. The study revealed that the risk of an increase in somatic cell count (SSC) and mastitis increased with advanced age and in animals with higher parity. The highest infection rate of 71.4 % was found in the age group >9 years followed by cows with higher than fifth parity (65.5 %). On severity and quarter basis, cows of <3 years of age had higher occurrence (12.5 %) of severe mastitis. From the present study, it may be concluded that a positive relationship exists between increased prevalence of mastitis and high SCC and the advance in age and parity of Holstein cows. 相似文献
35.
Sachin V Wandkar Pravin P Jadhav Babasaheb S Gholap Vikas V Gonjari Shashikant G Pawar 《农业工程》2014,4(2):110-111
对一些有特殊要求的农场来说,耕作机具牵引需求数据的有效性对于选择适当的耕作机具是极为重要的。机具宽度、作业深度、前进速度、土壤情况和机具机型都影响着机具的牵引。利用放置在砂壤土中的数字荷重单元对不同前进速度(0.69、1.11和1.52 ms)和耕作深度(100、150和200 mm),两种主要耕作机械牵引的影响进行了研究。采用的工具包括3个底圆盘犁和2个底型铧式犁。在两种方案中,速度和深度都随着工具牵引增加而增加。所有的工具牵引对深度的影响大于对速度的影响。在所有的前进速度和耕作深度的处理中,铧式犁的测量值均大于圆盘犁。基于速度和深度,对两种特殊牵引模拟了一般回归方程。 相似文献
36.
Sunil Nepal Vikas Kumar Harinder P. S. Makkar Timo Stadtlander Nicholas Romano Klaus Becker 《Fish physiology and biochemistry》2018,44(1):143-162
Jatropha seed cake (JSC) is an excellent source of protein but does contain some antinutritional factors (ANF) that can act as toxins and thus negatively affect the growth and health status of fish. While this can limit the use of JSC, detoxified Jatropha protein isolate (DJPI) may be a better option. An 8-week study was performed to evaluate dietary DJPI to common carp Cyprinus carpio. Five iso-nitrogenous diets (crude protein of 38%) were formulated that consisted of a C ontrol (fish meal (FM) based protein), J 50 or J 75 (50 and 75% of FM protein replaced by DJPI), and S 50 or S 75 (50 and 75% of FM protein replaced by soy protein isolate, SPI) and fed to triplicate groups of 75 carp fingerlings (75; av. wt. ± SD; 11.4 ± 0.25 g). The growth, feeding efficiencies, digestibility, plasma biochemistry, and intestinal enzymes were measured. Results showed that growth performance of fish fed the S 75- or DJPI-based diets were not significantly different from those fed the C ontrol diet, while carp fed the S 50 had significantly better growth than the J 75 diet. Fish fed the J 75 diet had significantly lower protein and lipid digestibility as well as significantly lower intestinal amylase and protease activities than all other groups. However, all plant protein-based diets led to significantly higher crude protein, crude lipid, and gross energy in the body of common carp compared to the control treatment. Plasma cholesterol and creatinine significantly decreased in the plant protein fed groups, although plasma triglyceride as well as the red blood cells count, hematocrit, albumin, globulin, total plasma protein, and lysozyme activity were higher in plant protein fed groups compared to FM fed group. White blood cells, hemoglobulin concentration, alkaline phosphatase and alanine transaminase activities, and glucose level in blood did not differ significantly among treatments. The results suggest that the DJPI is non-toxic to carp and can be used to replace FM in the diets of common carp up to 75%, but further research to potentially reduce some inherent ANF within this protein source, such as non-starch polysaccharides, may improve nutrient utilization. 相似文献
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38.
The ubiquity of the Internet has made disseminating information across geographical boundaries a relatively easy task. Apart from text-based materials, the Internet provides an easy means to transmit images, sound, video, and other multimedia content to a global audience, making it an ideal medium for establishing distance learning programs. Two Internet-based distance learning courses were developed to teach animal physiology to veterinary technicians in the School of Veterinary Medicine at Purdue University. These distance learning course sites are designed to take advantage of multimedia technology to enhance students' learning experiences. Multimedia has been used in education to make the learning process more engaging and interactive. The two course sites have a number of multimedia features that complement the textual subject matter. This article describes the features of the course Web sites and summarizes our experiences in designing and conducting Web-based physiology courses to distance learners. In addition, we describe the characteristics of our distance learning students. 相似文献
39.
Glynn Mitchell Eric D Clarke Stuart M Ridley David W Bartlett Kevin J Gillen Shaheen K Vohra Daren T Greenhow John C Ormrod Peter Wardman 《Pest management science》2000,56(2):120-126
Amino‐substituted derivatives of 2‐ethyl‐1,3,4(2H)‐isoquinolinetrione have been prepared with the aim of enhancing their hydrolytic stabilities relative to other isoquinolinetriones, and hence potentially improving their herbicidal effects. 5‐Amino‐2‐ethyl‐1,3,4(2H)‐isoquinolinetrione has been shown to be 12 and 8 times more stable towards hydrolysis than the isomeric 7‐ and 8‐amino derivatives, respectively, and 120 times more stable than 2‐ethyl‐1,3,4(2H)‐isoquinolinetrione itself. Pulse radiolysis studies have shown 5‐amino‐2‐ethyl‐1,3,4(2H)‐isoquinolinetrione to have free‐radical properties which could enhance the generation of superoxide radicals in plants. The compound is a potent stimulator of the light‐dependent consumption of oxygen at photosystem I in isolated chloroplasts and also shows high activity in isolated leaf discs. Evidence is presented which indicates that the rate of foliar uptake is a major factor affecting herbicidal activity for this compound. © 2000 Society of Chemical Industry 相似文献
40.
Vikas Kumar N. P. Sahu A. K. Pal Shivendra Kumar Amit Kumar Sinha Jayant Ranjan Kartik Baruah 《Fish physiology and biochemistry》2010,36(3):491-499
A 60-day experiment was conducted to study the effect of dietary gelatinized (G) and non-gelatinized (NG) starch on the key
metabolic enzymes of glycolysis (hexokinase, glucokinase, pyruvate kinase, and lactate dehydrogenase), gluconeogenesis (glucose-6
phosphatase and fructose-1,6 bisphosphatase), protein metabolism (aspartate amino transferase and alanine amino transferase),
and TCA cycle (malate dehydrogenase) in Labeo rohita juveniles. In the analysis, 234 juveniles (2.53 ± 0.04 g) were randomly distributed into six treatment groups each with three
replicates. Six semi-purified diets containing NG and G cornstarch, each at six levels of inclusion (0, 20, 40, 60, 80, and
100) were prepared viz., T1 (100% NG, 0% G starch), T2 (80% NG, 20% G starch), T3 (60% NG, 40% G starch), T4 (40% NG, 60%
G starch), T5 (20% NG, 80% G starch), and T6 (0% NG, 100% G starch). Dietary G:NG starch ratio had a significant (P < 0.05) effect on the glycolytic enzymes, the highest activities were observed in the T6 group and lowest in the T1 group.
On the contrary, the gluconeogenic enzymes, the glucose-6-phosphatase and fructose-1,6 bisphosphatase activities in the organs,
liver and kidney were recorded highest in the T1 group and lowest in the T6 group. The liver aspartate amino transferase activity
showed an increasing trend with the decrease in the dietary G level. However, the muscle aspartate amino transferase activity
was not significantly (P > 0.05) influenced by the type of dietary starch. The alanine amino transferase activity in both liver and muscle showed an
increasing trend with the decrease in the dietary G level. The liver and muscle malate dehydrogenase activities were lowest
in the T6 group and highest in the T1 group. Results suggest that NG (100%) starch diet significantly induced more the enzyme
activities of amino acid metabolism, gluconeogenesis, and TCA cycle, whereas partial or total replacement of raw starch by
gelatinized starch increased the glycolytic enzyme activity. 相似文献