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91.
A power plant that utilizes turkey manure as fuel to produce energy was built in Benson, Minnesota, and started full energy production in 2007. The plant was built to meet legislative requirements governing the use of renewable sources to generate energy in Minnesota. Although the use of turkey manure as biofuel generates energy, it also results in turkey manure ash (TMA) as a by‐product that contains phosphorus (P), potassium (K), sulfur (S), and zinc (Z) as well as other essential and nonessential elements. A 2‐year study was conducted to compare TMA with triple‐superphosphate and potassium chloride fertilizers as a source of nutrients for alfalfa (Medicago sativa) at three locations: Lamberton, Morris, and Appleton, Minnesota. The soils at Lamberton and Appleton were acidic with P and K concentrations ranging from medium‐high to very high, whereas the soil at Morris was alkaline with high concentrations of P and K. The experiment consisted of a control (0 P and 0 K) and annual and split applications of TMA and fertilizer. Annual TMA and fertilizer rates were 84 kg P2O5 ha?1, 118 kg K2O ha?1, and 34 kg S ha?1. Split rates were 42/42 kg P2O5 ha?1, 59/59 kg K2O ha?1, and 17/17 kg S ha?1. However, because of an overestimation of citrate‐soluble P in 2005 for the TMA, the total amount of available P applied with the TMA for the 2‐year study was 168 kg P2O5 ha?1 compared with 286 kg P2O5 ha?1 for the fertilizer. In the first year, fertilizer resulted in greater alfalfa biomass yield than TMA and the control, whereas in the second year, alfalfa yields with TMA and fertilizer were similar and both more than the control. In 2005, TMA resulted in more copper (Cu) and S tissue concentrations than the fertilizer. In 2006, application of both sources increased tissue P and S concentrations compared with the control. The TMA increased tissue Cu concentration and Zn plant uptake compared with fertilizer. Bray P1–extractable soil P concentrations were less with TMA and control treatments than with the fertilizer treatments. Ammonium acetate–extractable soil sodium (Na) concentrations were greater with TMA than with fertilizer and the control. By the second year, both ash and fertilizer treatments resulted in more K uptake than the untreated control with no difference in K uptake between the two sources or time of application. Both sources were effective in increasing P uptake compared with the untreated control. TMA was shown to be an effective source of nutrients for alfalfa production.  相似文献   
92.
One‐day‐old female turkeys were randomly assigned to five dietary treatments and were fed for 15 weeks diets containing 5% of cellulose (control, C) or 5% of dried fruit pomaces (apple, black currant, strawberry, seedless strawberry; AP, BCP, SP, SSP respectively). In weeks 11–15 of feeding, all diets were supplemented with 2.5% of linseed oil. The crude fibre content of fruit pomaces ranged from 56.5% in AP to 62.9% in SP. In comparison with AP, berry fruit pomaces (BCP, SP and SSP) were characterised by a higher content of neutral detergent fibre – NDF (41.2% vs. 52.7–59.3%) and lignin (13.24% vs. 21.80–25.56%). A monomer analysis revealed that cellulose was the main non‐starch polysaccharide (NSP) in fruit pomaces, whereas their pectin content was low. Polyphenol content was determined at below 6 g/kg in AP, at approximately 12 g/kg in BCP and SP, and at 32.8 g/kg in SSP. There were no significant differences (p > 0.05) in final body weight of birds. After 15 weeks of feeding fruit pomaces to turkeys, the relative weight of the small intestine with digesta was higher in group AP, and lower in group SSP, as compared to controls. Dietary fruit pomaces decreased the dry matter (DM) concentration and lowered the pH of the small intestinal digesta, except the AP and SSP treatments respectively. In the caeca, significantly reduced concentrations of ammonia or putrefactive short‐chain fatty acids (SCFA) upon dietary fruit pomaces were observed. Fruit pomaces did not influence the concentrations or the total pool of short‐chain fatty acids, but led to a significant increase in butyric proportion in the SCFA profile at the expense propionate.  相似文献   
93.
94.
This study was performed to investigate the effects of β-hydroxy-β-methylbutyrate (HMB) administration on skeletal system properties in turkeys. Thirty-two males were randomly divided into two groups at the age of 35 days of life. The first group included control turkeys (n = 16) treated with placebo, while the second group of birds (HMB group; n = 16) was administered orally with calcium salt of HMB during the last 15 weeks of life. The turkeys were sacrificed at the age of 20 weeks and tibia was isolated for analysis of bone geometrical parameters, volumetric bone mineral density (vBMD) and mechanical properties. Furthermore, assessment of free amino acid concentrations in plasma was performed. The results showed a 6.3% increase of vBMD of tibia in response to HMB treatment (p < 0.01). Cross-sectional area, second moment of inertia, maximum elastic strength and ultimate strength of tibia were significantly increased in HMB-treated turkeys by 21.3%, 49.0%, 27.2% and 28.3%, respectively (p ≤ 0.01). β-hydroxy-β-methylbutyrate administration increased plasma concentrations of proline,glutamate, leucine, isoleucine, valine, alanine, aspartate, phenylalanine and cysteic acid (p < 0.05). These results indicate that long-term administration of HMB improves vBMD, and geometrical and mechanical properties of skeletal system in turkeys, and that these effects are associated with improved plasma amino acid concentrations.  相似文献   
95.
本实验以Lasota疫苗点眼、滴鼻免疫21日龄火鸡,研究其盲肠扁桃体、哈德尔腺和支气管粘膜淋巴组织的免疫应答。结果如下:免疫火鸡上述局部免疫组织的浆细胞、酯酶阳性T细胞及淋巴细胞显著增多,巨噬细胞程度不等地增加;盲肠扁桃体淋巴小结增多、增大。这表明,免疫火鸡消化道和呼吸道局部免疫组织不仅体液免疫应答显著加强,而且细胞免疫反应也明显增强。NDD 强毒攻击后,免疫火鸡呼吸道和消化道局部免疫组织的体液免疫和细胞免疫水平进一步升高;对照火鸡则出现细胞免疫和体液免疫机能衰竭。  相似文献   
96.
97.
Eggs from young turkey breeder hens have a higher rate of early embryonic mortality (EEM) than eggs from older hens. Preliminary field data indicated that increased sperm concentration decreased the incidence of EEM in eggs from young hens. Possible explanations for decreased EEM following insemination with more concentrated sperm may include altered sperm binding and hydrolyzing of the inner perivitelline layer (IPVL) of eggs from hens of different ages. The current study examined differences in the number of sperm penetration (SP) holes hydrolyzed in the IPVL in hens at 2 different ages when inseminated with 25, 50, 100, 200, 400, or 800 million viable sperm. Hens (12/treatment) were inseminated on d 14 and 21 after photostimulation (32 and 33 wk of age) and were inseminated again at 12 and 13 wk of egg production (44 and 45 wk of age). The SP holes hydrolyzed in the IPVL were counted in the 1,098 eggs produced in the 3 wk following each insemination period. The number of SP holes hydrolyzed in the IPVL was significantly (P ≤ 0.05) greater in younger hens than older hens. Furthermore, the number of SP holes was significantly greater (P ≤ 0.01) with the 400 and 800 million insemination doses as compared with the other 4 insemination doses. There was no interaction between hen age and sperm insemination dose. In conclusion, the absence of an interaction between hen age and insemination dose suggests that factors other than numbers of sperm binding to the IPVL influence EEM. These factors may be a combination of oviduct influences and IPVL properties that change as the hen ages.  相似文献   
98.
退耕草地全牧火鸡育肥效果研究   总被引:3,自引:0,他引:3  
罗富成  陈功 《草业科学》2003,20(8):39-40
退耕草地全牧火鸡育肥试验表明:云南火鸡人工草地全牧饲养,可缩短育肥周期、降低饲料成本、提高经济效益,火鸡每增重1kg较农村传统饲养方式少耗精料2.09kg,节约饲料费用2.05元;云南火鸡在9~10周龄为增重高峰阶段,10周以后,生长减慢。为了取得较好的经济效益,在生产上除了要求饲草数量充足、品质好以外,云南火鸡在10周龄以后还应适当加强补饲。  相似文献   
99.
作者对火鸡传染性鼻气管炎病毒(ARTV)对鸡致病性进行了初步的研究,发现大肠杆菌在本病的发生过程中起着重要的协同作用。首先对鸡的肝、肾进行攻毒,然后分离病毒,经鸡胚多次传代后,鸡胚出现矮小,头部出血,有时全身出血。取鸡胚尿囊液,经负染,在电子显微镜下观察发现有密集的呈球形的病毒颗粒。  相似文献   
100.
Two experiments and 3 field trials were conducted to examine the usefulness of a novel bedding material for rearing Large White commercial turkeys. The control bedding was pine shavings (PS) in both experiments and all trials. The novel bedding, aGroChips (AC), is a chopped paper product made from cotton lint waste, gypsum, and old newsprint following a proprietary paper manufacturing process. In both experiments, hens and toms were reared according to typical industry techniques. In the first experiment, use of AC resulted in significantly (P <0.05) heavier toms and hens. In the second, the toms brooded and reared on AC were significantly (P <0.05) heavier than those brooded and reared on PS, whereas toms brooded on one bedding and then reared on the other were intermediate in weight. There were no differences in final cumulative FCR or carcass yield in either experiment. Three field trials were conducted with Large White commercial turkey hens in which the hens were brooded either on PS or AC, with both groups reared on PS. There was a mean increase of 0.2 kg in BW, a decrease (improvement) of 0.03 in FCR, and an increase of 3,200 kg per trial for AC-brooded birds (based on 16,000 hens placed per brooder house). A hard, dry litter crust was observed in the AC houses. With subsequent testing, further changes in the manufacturing process to create a hard, durable pellet may result in a more usable and useful bedding material.  相似文献   
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