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51.
Information is presented on the nature, extent and spatial distribution of waterlogged areas and salt-affected soils, derived through systematic visual interpretation of standard false colour composite (FCC) prints on a 1:100 000 scale generated from the Indian Remote Sensing Satellite (IRS-1B) Linear Imaging Self-scanning Sensor (LISS-I) and Landsat–Thematic Mapper (TM) data for the Nagarjunsagar Right Bank Canal Command Area, Andhra Pradesh. A total of 1710 ha of land in the coastal region has been found to be waterlogged. Salt-affected soils cover an area of 42 800 ha, with saline–sodic soils covering 28 480 ha emerging as the dominant category. To make optimal use of these lands and to prevent further degradation both preventive and ameliorative measures have been advocated. © 1998 John Wiley & Sons, Ltd.  相似文献   
52.
The effect of ad libitum (ADLIB) feeding strategy on the fertility of the group housed sow was studied in a prospective field trial during 1.5 years. All study animals farrowed under standard farrowing circumstances in crates, and they were provided with an ad libitum feeding throughout the 30‐day lactation. After weaning, animals were randomly allocated to one of the two dry sow feeding strategies (AD LIB or CONT). After oestrus detection in groups, they were artificially inseminated and moved into pregnancy pens with partially slatted floor, in groups of 40 sows each. The ADLIB sows (n = 447) were loose housed and provided with ad libitum access to 7.7 MJ/kg feed high in fibre from two feeders per group. The control sows (n = 479; CONT) were also loose housed and given a standard dry sow feed in feeding stalls once a day (2.5 kg/day. The energy content of the feed was 9.3 MJ/kg NE). The feeding strategy (ADLIB vs CONT) had no effect on pregnancy rate (85.8 vs 90.9, p > 0.05), weaning to oestrus interval (7.7 vs 7.3 days, p > 0.05), piglets born alive (11.5 ± 3.5 vs 11.6 ± 3.3, p > 0.05), stillborn piglets (1.2 ± 1.8 vs 0.9 ± 1.5, p > 0.05) nor on progesterone concentration (p > 0.05). CONT sows weaned more piglets (9.7 ± 2.2 vs 9.4 ± 2.0, p < 0.01), whereas the piglets of AD LIB sows were heavier at weaning (8.8 ± 0.9 vs 8.0 ± 1.3 kg, p < 0.05). In conclusion, ad libitum feeding with a high in fibre diet during pregnancy did not affect the reproductive performance.  相似文献   
53.
Extracts of Bacopa monniera (Brahmi, BM), a traditional ayurvedic medicine, have been reported to have memory-enhancing effects in animals. However, there are no studies in which different dosages or chronic use have been explored. The current study examined the effects of standardized extract of BM on behavioral changes of Wistar rats when administered the extract for various durations and in varying doses. We divided the animals into 2-, 4-, and 6-week treatment groups. Rats in each of these groups were divided into 20 mg/kg, 40 mg/kg, and 80 mg/kg dose groups (n = 8 for each dose). After the treatment period, the rats, along with age-matched normal and gum acacia control rats, were subjected to spatial learning (T-maze) and passive avoidance tests. The data were compared with those of age-matched control rats. The study was conducted at the Melaka Manipal Medical College, Manipal University, Manipal, Karnataka, India. The results showed improvement in spatial learning performance and enhanced memory retention in rats treated with BM extract. These results clearly indicate that oral administration of BM extract improved learning and memory in rats.  相似文献   
54.
Four complete isonitrogenous (crude protein 13%) rations with 0 (T1), 5 (T2), 10 (T3) and 15 (T4) per cent calcium soap from red palm oil (protected fat) were formulated and evaluated using four Deccani lambs (19.32 ± 0.82 kg) in a completely randomized design at the end of a growth trial. The average daily dry matter intake (% body weight or g/kg W0.75 per day) in lambs fed ration T4 was significantly (p < 0.05) lower than in those fed rations T1, T2, and T3. There was no significant difference in the digestibility of proximate principles and cell-wall constituents except for ether extract (EE) and cellulose. EE digestibility was significantly (p < 0.05) higher by 15.71, 14.65 and 11.56 percentage units, respectively in lambs fed rations T2, T3 and T4 as compared to those fed ration T1. Ration T4 had significantly (p < 0.05) lower cellulose digestibility than rations T1, T2 and T3. Nitrogen and phosphorous balances (g/day) were not significantly (p > 0.05) different among the four rations. Calcium balance (g/day) was higher by 0.65, 1.39 and 1.40, respectively, in lambs fed rations T2 (p > 0.05) and T3 and T4 (p < 0.05) in comparison to those fed ration T1. Digestible crude protein and total digestible nutrients content (g/kg DM) of rations were not significantly (p > 0.05) different among the four rations. It is concluded that calcium soap from red palm oil can be supplemented up to 10% level as a concentrated energy source in the rations of Deccani lambs without any adverse effect on dry matter intake and cellulose digestibility.  相似文献   
55.
毛皮动物一般指那些能提供高档裘皮产品的动物,属于野生或经过人工驯化饲养的哺乳类动物。作者对毛皮动物的栖息环境、采食习性、行为等野生习性及驯化的关键问题和方法进行了综述。  相似文献   
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