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Mortality patterns of two Zebu cattle breeds, Sahiwal and Tharparkar, and two crossbred strains, Karan Swiss and Karan Fries, maintained at the National Dairy Research Institute, Karnal were studied. Nine-year (1989--90 to 1997--98) data on mortality were analysed for year, season, age and cause effects on mortality rate. The overall mortality was 14.17%. The mortality in Sahiwal, Tharparkar, Karan Swiss and Karan Fries averaged 14.35%, 7.21%, 17.12% and 13.46%, respectively. The breed mortality rate did not vary significantly between years, seasons, age categories and causes of disease. However, the trends indicated appreciable difference in mortality rates. The mortality was highest in the year 1994--95 (19.53%) and lowest in 1991--92 (8.56%). There was very little variation in seasonal mortality rate and mortality rate averaged 4.53%, 4.81% and 4.84% in hot-dry (March-June), hot-humid (July-October) and cold (November-February) seasons, respectively. The mortality up to 2 months of age accounted for a major share (50-60% or higher) in different breed groups. Digestive problems followed by respiratory disorders together accounted for 70-80% of total deaths.  相似文献   
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The in vitro inhibitory effect of protease inhibitors from four seed extracts (soybean, grasspea, black gram and horse gram) on digestive proteases of rohu was assessed by enzyme inhibition assay and substrate sodium dodecyl sulphate‐polyacrylamide gel electrophoresis. High proteolytic activity was detected in the intestinal extract of rohu (Labeo rohita) fingerlings at two different pH ranges (8–8.5 and 10–11). That protein digestion occurs mainly in the alkaline condition in this fish without a stomach is evident from very high trypsin activity (0.95±0.04 benzoyl‐dl ‐arginine‐p‐nitroanilide U mg protein−1) in the intestine. In case of grass pea seed, more than 50% inhibition of alkaline protease activity was recorded when the ratio of inhibitor to enzyme was 9.41 μg U−1. More than 40% inhibition of protease activity was recorded in case of horse gram seed when the ratio of inhibitor to enzyme was 5.51 μg U−1. Black gram at 11.0 μg U−1 and soybean seed proteins at 62.75 μg U−1 resulted in 50% and more than 30% inhibition of digestive protease activity in rohu fingerlings respectively. A plot of the inhibition values obtained by changing the relative concentrations of enzyme/inhibitor resulted in different dose–response curves for different protein sources. The use of substrate gel electrophoresis allowed the visualization of the aforementioned differences in inhibition. Each seed extract produced a characteristic profile of protease inhibition. It is concluded that protease inhibitors present in plant protein sources adversely affect the digestive proteases in fish and hence there is a need to eliminate/reduce the amount of such inhibitors through proper processing before incorporation into aquafeeds.  相似文献   
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The underlying principles and traditional knowledge concerning indigenous agroforestry systems (AFS) around the world have been used successfully in the design of improved systems; but lately there has been a slow-down in that effort. Recognizing that Cinderella, by analogy, refers to an individual whose attributes were unrecognized or one who unexpectedly achieved success after a period of obscurity and neglect, we propose Cinderella agroforestry systems for such underexploited and “forgotten” AFS. In order to highlight their unrecognized potentials, a few such systems that are location-specific and little-known outside their areas of existence were selected from around the world. Each selected system is unique in terms of its production, environmental, and sociocultural attributes; but none had been described in quantitative terms of ecology and production. A qualitative SWOT (strengths–weaknesses–opportunities–threats) analysis of the systems showed several commonalities among them. While sustainability, multi-functionality, and high sociocultural values are common strengths, low levels of production and lack of research- and technology inputs to improve the system are the major weaknesses. The opportunities emanating from strengths and weaknesses are also common to all the systems; and “threats” to these systems arise mostly from ramifications of government policies. Given the acknowledged role of AFS in climate-smart agriculture and the current global momentum for working with communities to better manage landscapes, learning from success stories of the Cinderella AFS could suggest models for sustainable development, and efforts in that direction should also be incorporated into global agroforestry research agendas.  相似文献   
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1. Alterations in glucose tolerance and, insulin, glucagon and adrenaline responses in dexamethasone (DXM)‐treated (induced hypocorticalism) chicks have been evaluated chronologically during the first month of development of White Leghorn chicks.

2. Alterations in glucose tolerance and, insulin resistance and glucagon and adrenalin responses in dexamethasonised chicks were recorded. Control chicks too displayed differential glucose tolerance and, insulin, glucagon and adrenaline responses on a chronological basis.

3. The observations suggest increased insulin and adrenaline sensitivity in the first fortnight and gradually increasing glucagon response in the second fortnight in neonatal chicks.

4. Furthermore, increased insulin sensitivity and attenuated glucagon responsiveness was also associated with DXM‐induced hypocorticalism.  相似文献   

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我们于2007年至2009年通过食丸分析研究了印度泰米尔纳德邦马杜赖地区横斑腹小鸮(Athene brama)的食性及猎物谱.共分析了食丸4181个,记录了共16种猎物的40278个残余物.每个食丸中的猎物种类为1-31个,平均9.6±3.03个.分析表明,该地区横斑腹小鸮的主要猎物为无脊椎动物(昆虫类占83.0%,蛛...  相似文献   
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