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1.
This study was designed to analyze the low input backyard poultry production system practiced by the tribal farmers, and evaluate the performance of an improved dual-purpose breed, the Vanaraja. Results revealed that a significantly (p < 0.05) higher number of farmers used temporary, non-conventional poultry houses made of locally available materials, such as bamboo and wood. Most of the farmers (65.9 %) did not provide balanced feed to their poultry and did not vaccinate their birds against any disease. Under standard management conditions, the average body weight of Vanaraja birds at 6 weeks was 625 +/- 10.9 g. Under backyard conditions, the body weight at 18 months was 3.6 +/- 0.8 kg. The age at first egg was 154 +/- 9 days in the backyard system, whereas under the intensive system it was 196 +/- 4 days. Annual production under the backyard and intensive systems of rearing was 176 +/- 9 and 152 +/- 7 eggs, respectively. Mortality of adult birds was 12 % and predation by foxes and wild cats accounted for 1.67 %. This study revealed that village chickens are an important income source for household expenses, and that traditional free-range poultry production in the smallholder sector of developing countries can possibly be improved through the use of improved dual-purpose birds.  相似文献   
2.
以“空间序列”代替“时间序列”的方法对渝西地区不同恢复方式下不同年龄的火烧迹地进行了调查研究,结果表明:火烧迹地的植被均匀度、丰富度和Shannon-Wiener指数等随恢复年限的变化曲线在人工恢复和自然恢复两种情况下有很大差异.实验中看不出两种恢复方式的不同是否能决定群落最终的物种多样性水平,但是不同的恢复方式可以加快或减缓物种多样性恢复的过程.实验还表明:在人工恢复的35年以内,多样性的恢复是一个“S”形变动的过程.人工恢复可以缩短灌木丛阶段的年限,加快乔木层的建成,同时促使该类型林区更长时间的停留在针叶林阶段,推迟该林区向顶级群落的演替进程;在自然恢复的40年以内,多样性的恢复是一个逐渐上升的过程,在最初的8年以内,其多样性不如人工恢复,但在恢复40年左右的时候,其多样性却可以达到一个比人工恢复高很多的水平.  相似文献   
3.
A comparative study of Frequency Ratio(FR)and Analytic Hierarchy Process(AHP)models are performed for forest fire risk(FFR)mapping in Melghat Tiger Reserve forest,central India.Identification of FFR depends on various hydrometeorological parameters altitude,slope,aspect,topographic position index,normalized differential vegetation index,rainfall,air temperature,land surface temperature,wind speed,distance to settlements,and distance by road are integrated using a GIS platform.The results from FR and AHP show similar trends.The FR model was significantly higher accurate(overall accuracy of 81.3%,kappa statistic 0.78)than the AHP model(overall accuracy 79.3%,kappa statistic 0.75).The FR model total forest fire risk areas were classified into five classes:very low(7.1%),low(22.2%),moderate(32.3%),high(26.9%),and very high(11.5%).The AHP fire risk classes were very low(6.7%),low(21.7%),moderate(34.0%),high(26.7%),and very high(10.9%).Sensitivity analyses were performed for AHP and FR models.The results of the two different models are compared and justified concerning the forest fire sample points(Forest Survey of India)and burn images(2010-2016).These results help in designing more effective fire management plans to improve the allocation of resources across a landscape framework.  相似文献   
4.
Reproductive performance of crossbred cows reared under traditional low input production system was assessed. A total number of 160 farmers were surveyed and traditional fodders were evaluated for proximate composition. Total protein, albumin and cholesterol concentrations in blood serum were analyzed. The age at first service, age at first calving, calving interval, calving to first service and calving to conception interval were calculated from records of 261 crossbred dairy cows. The crude protein, crude fiber, nitrogen free extract, ether extract and total ash content varied from 7.2 to 13.9, 18.2 to 34.4, 39.1 to 59.2, 2.1 to 4.1 and 7.2 to 17.9%, respectively. The total protein and albumin concentrations in blood serum were 7.6 ± 0.3 and 4.3 ± 0.3 g/dl, respectively. The cholesterol concentration was 221.1 ± 8.2mg/dl. The mean age at first service and age at first calving was 28.6 ± 1.0 and 40.7 ± 1.1months, respectively. The mean values for calving to first service and calving to conception intervals were 182 ± 14.5 and 224 ± 9.0days, respectively. The conception rate was significantly high among the cows that showed typical fern pattern of cervical mucus (56.6%). The conception rate based on 1st insemination was 44.4%. The incidence of repeat breeders and anestrus among the crossbred cows were 12.8 and 14.1%, respectively.  相似文献   
5.
在对中国西南山地热点地区的生物多样性快速评估调查中得出康定、丹巴、雅江三地有种子植物115科,486属,1 385种; 其中,裸子植物5科,12属,36种; 被子植物110科,474属,1 349种.区系分析显示该植物区系起源古老,地理成分复杂,整体有明显的过渡性; 在科与属级水平上,呈现出明显的泛热带和温带特性; 该区优势分类群明显,单种属和少种属异常丰富.  相似文献   
6.
The aim of the study was to determine the effect of feeding feed blocks containing varying proportion of urea-treated paddy straw (UTPS) on dry matter (DM) intake (DMI), nutrient utilization and N balance in Mithun. For the purpose, four adult male Mithun (279.5 ± 8.2 kg) were selected and offered four experimental rations viz. R1 (Napier fodder + concentrate at 60:40), R2 (UTPS + concentrate at 50:50), R3 (UTPS + concentrate at 60:40) and R4 (UTPS + concentrate at 70:30) in 4 × 4 Latin square design. The DMI % of body weight was 2.59, 2.96, 2.85 and 2.77 and the DMI g kg−1 W0.75 was 107, 123, 118 and 115 in Mithun fed R1, R2, R3 and R4, respectively. The mean DMI was (P < 0.01) higher in animals fed R2 and R3 than R1 and R4, whereas the water intake was (P < 0.01) higher in Mithun fed R2, R3 and R4 than R1. The digestibility of DM, organic matter, crude protein, crude fibre, neutral detergent fibre and cellulose were (P < 0.05) higher in animals fed R2, R3 and R4 than R1. A positive N balance was observed in all the experimental animals, with higher (P < 0.05) values among the animals offered R2, R3 and R4 than R1. The digestible crude protein and total digestible nutrient intakes were higher (P < 0.05) in Mithun fed R2 and R3 than R1 and R4. It is concluded that the UTPS can be incorporated up to 70% to formulate the complete feed/feed block and can be used for feeding of Mithun under complete confinement system.  相似文献   
7.
Nutrient management plays an important role in yield and quality of tomatoes. A field experiment was conducted during the years 2008–09 and 2009–10 to analyze the effect of organic and conventional sources of fertilizer on yield and quality of tomatoes in an acid lateritic soil of India. The organic sources of fertilizer were vermicompost (VC), crop residue (CR), vermiwash (VW) and biofertilizer (BF). The conventional input was chemical fertilizer (CF) applied at recommended dose of 100:80:60 kg ha?1 of N:P2O5:K2O for the tomato. The organic source VC was used to supply 100% N recommendation as single source or 50% N recommendation when combined with CF or organic sources. Maximum fruit yield was recorded when CF was applied at full dose, which was on a par with VC at full recommendation. A higher percentage of large-size fruits (>7 cm) was obtained in VC-based treatments compared with CF treatment. Vermicompost at full dose increased ascorbic acid, beta carotene, total soluble solids and color value compared with its half dose along with other organic sources (CR, BF). The potential exists to improve tomato fruit quality through a better nutrient management, whether it be conventional, organic or a combination of both.  相似文献   
8.
以"空间序列"代替"时间序列"的方法对渝西地区不同恢复方式下不同年龄的火烧迹地进行了调查研究,结果表明:火烧迹地的植被均匀度、丰富度和Shannon-Wiener指数等随恢复年限的变化曲线在人工恢复和自然恢复两种情况下有很大差异.实验中看不出两种恢复方式的不同是否能决定群落最终的物种多样性水平,但是不同的恢复方式可以加快或减缓物种多样性恢复的过程.实验还表明:在人工恢复的35年以内,多样性的恢复是一个"S"形变动的过程.人工恢复可以缩短灌木丛阶段的年限,加快乔木层的建成,同时促使该类型林区更长时间的停留在针叶林阶段,推迟该林区向顶级群落的演替进程;在自然恢复的40年以内,多样性的恢复是一个逐渐上升的过程,在最初的8年以内,其多样性不如人工恢复,但在恢复40年左右的时候,其多样性却可以达到一个比人工恢复高很多的水平.  相似文献   
9.
Replacement of fish meal with squilla silage in practical diet for the juvenile giant freshwater prawn, Macrobrachium rosenbergii, was evaluated. Five iso-nitrogenous and iso-caloric diets were prepared in which protein requirements were met with 100% fish meal (control, diet 1) and squilla silage replacing fish meal at 25, 50, 75 and 100% (diets 2, 3, 4 and 5, respectively). Water stability and water absorption of five feeds revealed significant differences (P?<?0.05). The weight gain varied between a maximum of 248.50?±?34.07% in diet 4 to lowest 132.45?±?14.34% in diet 1. The average daily gain in weight in grams varied from 0.091?±?0.01 (diet 5) to 0.154?±?0.04 (diet 3), whilst the specific growth rate and gross growth coefficient values were recorded highest in diet 4. Highest survival rates (86.66?±?5.77%) were recorded in both experimental diets 4 and 5. Low feed conversion ratio of 1.19?±?0.21 was recorded from diet 4, whilst the highest value of 2.16?±?0.09% was estimated from the diet 5. Proximate carcass composition showed highest crude protein content in post-larvae fed with diet 5 (47.24%) in contrast to lowest diet 1 (36.12%). Lipid values fluctuated significantly between 2.45 and 7.18% (P?<?0.05) between treatments. The ash content significantly increased from diet 1 (16.34%) to diet 5 (20.69%) (P?<?0.05). Highest feed efficiency (gain/feed) value was recorded in diet 4 (1.52?±?0.22), whilst the diet 5 showed lowest value (0.99?±?0.06). The results suggested that squilla silage can be utilised up to 75% of the protein in prawn diets for fish meal replacement.  相似文献   
10.
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