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1.
This study compared the feed preference and growth response of Litopenaeus vannamei to chemoattractants. A diet with 3% fishmeal was supplemented with either 3% salmon meal (POS), 3% soy protein concentrate (NEG), 3% krill meal (KRM), 3% squid meal (SQM), 3% shrimp head meal (SHM), 3% shrimp meal (SM), 3% squid liver meal (SLM), or 5% liquid sardine hydrolysate (SAH). Shrimp with a body weight (BW) of 0.99 ± 0.08 g were stocked at 100 animals/m2 in 56 tanks of 1 m3 and fed 10 times daily for 74 days. Feed preference was evaluated by feeding shrimp of 10.87 ± 1.82 g in excess twice a day for 10 days in two separate feeding trays allocated in 50 tanks of 0.5 m3. Survival reached 93.3 ± 5.80% and was unaffected by supplementation. Final BW was the highest for shrimp fed the KRM‐supplemented diet (11.97 ± 0.93 g), followed by POS (11.11 ± 0.77 g) and SQM (11.01 ± 1.17 g). Diets SHM, SM, SLM, and NEG showed a lower shrimp BW than POS, but were not statistically different among them. Shrimp fed the SAH diet achieved the lowest BW (10.06 ± 1.02 g). The highest gained yield was obtained with diets KRM and POS. No statistical difference was observed in shrimp yield among other diets. The lowest feed conversion ratio (FCR) was achieved with shrimp fed KRM (1.31 ± 0.05) when compared to diets SHM (1.47 ± 0.05), SAH (1.47 ± 0.07), and SLM (1.45 ± 0.17). Two‐by‐two comparisons indicated that shrimp preferred SHM and KRM, except when these were compared to SQM and SLM. No difference in feed preference was found between diets with SQM and SLM. SAH was the least preferred raw material in all comparisons. Results indicated that KRM acts as a powerful feeding effector and growth enhancer in fishmeal‐challenged diets for whiteleg shrimp. A dietary supplementation with 3% KRM is more effective than the same dose of any other chemoattractant evaluated.  相似文献   
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In 7 normal healthy Egyptian one-humped camels aged 3-4 years, the relationships were studied between enzyme activities of lactic dehydrogenase (LDH), creatine phosphokinase (CPK), alkaline phosphatase (ALP), acid phosphatase (ACP), and cholonesterase (CHE) of serum and organs as well as between ACP and ALP and between LDH and CPK. Liver, heart, kidney, and spleen tissue samples as well as serum were analysed for total enzyme activity. The following results were obtained: --The heart was the organ with the highest activities of ALP, LDH, and CPK, and it contained high values of CHE, whereas the lowest activities of all enzymes were recorded from serum. The spleen exhibited of the highest activity of ACP. --Each of the serum enzymes ALP, LDH, and CHE were in strong inverse relationship with the corresponding enzymes in the liver. Strong inverse relationships existed also between serum LDH and kidney LDH as well as between CPK in serum and heart. --Direct relationships were remarkable serum LDH and that of spleen and heart as well as between serum ACP and that of liver and heart. --Interrelationships were inverse between ACP and ALP in liver, kidney, and heart, but weak direct interrelationships were characteristic between the 2 enzymes in serum and spleen. --LDH was inversely interrelated with CPK in serum and heart.  相似文献   
4.
The use of supplemental essential amino acids (EAAs) has been shown to provide an opportunity to minimize excess levels of crude protein (CP) in animal feeds. The present study investigated the effect of reducing the amount of CP in low‐fish meal diets (5%) for juvenile Litopenaeus vannamei. Four sets of diets were prepared containing (% on a fed basis, mean ± SD) 31.24 ± 0.71, 33.70 ± 0.41, 36.90 ± 0.44, and 39.63 ± 0.14% CP, with each protein level containing a total dietary methionine (Met) (Met + Cys) level of 0.56 ± 0.02 (1.07 ± 0.23), 0.71 ± 0.01 (1.22 ± 0.20), 0.88 ± 0.02 (1.38 ± 0.22), or 1.04 ± 0.02% (1.55 ± 0.18%). Shrimp of 1.00 ± 0.08 g were stocked in 84 outdoor tanks of 1 m3 at a rate of 100 shrimp/m2 and raised for 75 days. Final survival ranged from 83 to 97% and was unaffected by Met content. Both survival and yield were significantly depressed when shrimp were fed the 31% CP diet. Shrimp grew at a weekly rate of between 0.79 and 0.97 g, achieving a final body weight (BW) in excess of 10.8 g. There was a significant interaction between CP and Met over BW. Shrimp fed 0.56% Met achieved the lowest BW at harvest. Increasing CP beyond 34% did not enhance BW. With a dietary Met content of 0.71%, the highest BW was achieved with 34% CP compared to other levels. There was a significant improvement in Feed Conversion Ratio (FCR) when CP was raised from 31 to 34%. Similarly, dietary Met levels above 0.71% resulted in a significantly better FCR compared to 0.56%. Our study has shown that, if dietary Met (Met + Cys) meets a minimum of 0.71% (1.22%), levels of CP could be reduced from 40 to 34% without adverse effects on shrimp performance.  相似文献   
5.
The objective of the present study was to describe the prevalence and risk factors associated with cryptosporidiosis in buffalo calves in Middle Egypt. During one year, 458 fecal samples were collected from buffalo calves less than 3 month age in 55 small scale herds and examined for the presence of Cryptosporidium oocysts. Data describing age, gender, season, and herd management practices were gathered to assess potential risk factors. Fecal examination showed that 14.19% of the examined calves were positive for Cryptosporidium spp. Calves at 1-15 days were at the highest risk (P < 0.001), and a significant relationship between season and infection (P < 0.05) was recorded. A significant association between infection and hygiene (P < 0.001), type of floor (P < 0.01) and source of water (P < 0.01) was also recorded. Statistical analysis concerning the clinical signs and fecal characteristics revealed a significant association with fecal consistency (P < 0.001), presence of blood (P < 0.01) and mucous (P < 0.01). Moreover, a significant association was found between infection and the desire for suckling (P < 0.05) and tenesmus (P < 0.05). The results of the present study demonstrated the strong relation between infections by Cryptosporidium spp. and diarrhea in buffalo calves.  相似文献   
6.
Tropical Animal Health and Production - Panting syndrome and respiratory infection have been recorded in complicated cases of foot and mouth disease (FMD) in cattle. However, investigations on the...  相似文献   
7.
The aim of the present study was to carry out molecular epidemiological investigation on enterotoxigenic Escherichia coli (ETEC) K99 and Salmonella spp. in diarrheic neonatal calves. Fecal samples were obtained from 220 diarrheic calves at 9 farms related to four governorates in central and northern Egypt. E. coli and Salmonella spp. isolates were examined for E. coli K99 and Salmonella spp. using PCR. ETEC K99 was recovered from 20 (10.36 %) out of 193 isolates, whereas Salmonella spp. was recovered from nine calves (4.09%).Multivariable logistic regression was used to evaluate the risk factors associated with both infections. ETEC K99 was significantly affected by age (P < 0.01; OR: 1.812; CI 95%: 0.566–1.769), colostrum feeding practice (P < 0.01; OR: 5.525; CI 95%: 2.025–15.076), rotavirus infection (P < 0.001; OR: 2.220; CI 95%: 0.273–1.251), vaccination of pregnant dams with combined vaccine against rotavirus, coronavirus and E. coli (K99) (P < 0.001; OR: 4.753; CI 95%: 2.124–10.641), and vitamin E and selenium administration to the pregnant dam (P < 0.01; OR: 3.933; CI 95%: 0.703–1.248).Infection with Salmonella spp. was found to be significantly affected by the animal age (P < 0.05; OR: 0.376; CI 95%: 0.511–1.369), Hygiene (P < 0.05; OR: 0.628; CI 95%: 1.729–5.612), and region (P < 0. 01; OR: 0.970; CI 95%: 0.841–1.624).The results of the present study indicate the importance of PCR as rapid, effective and reliable tool for screening of ETEC and Salmonella spp. when confronted with cases of undifferentiated calf diarrhea. Moreover, identification of the risk factors associated with the spreading of bacteria causing diarrhea may be helpful for construction of suitable methods for prevention and control.  相似文献   
8.
Shortage of water in arid and semi-arid regions increases the need of applying efficient drip irrigation system. A two-year field study in the semi-arid region of Upper Egypt was carried in randomized complete block design with four replicates. Wheat plants were irrigated by 100 or 75% of water requirements (I100 = 5,370 and I75 = 4,027 m3 ha?1). Irrigation of wheat by I100 increased growth and uptake of nitrogen, phosphorus, and potassium compared to low irrigation level. I100 caused 14 and 5% increase in straw and biological yield, respectively, compared to I75. Grain yield and water use efficiency (WUE) were higher by 20 and 59% in the case of I75 compared to I100. The use of deficit irrigation in drip-irrigated wheat under arid conditions is an effective tool to maximize efficiency of water use; moreover, 4,027 m3 ha?1 is the optimum irrigation rate for maximum WUE and grain yield.  相似文献   
9.
A total of 30 horses were divided into two groups, one served as a control whereas other was rhabdomyolysis diseased horses. After blood collection, the resulted sera were used for estimation of the activities of creatin kinase (CK), aspartate transaminase (AST), lactate dehydrogenase (LDH), lactic acid, triacylglycerol (TAG), glucose, total protein, albumin, globulin, urea, creatinine, Triiodothyronine (T3), calcium, sodium, potassium, phosphorus, chloride, vitamin E, interleukin-6 (IL-6) and tumor necrosis-α (TNF-α). In addition, whole blood was used for determination of selenium, reduced glutathione (G-SH) and prostaglandin F2-α (PGF2α). The erythrocyte hemolysates were used for the determination of the activities of super oxide dismutase (SOD), catalase (CAT), total antioxidant capacity (TAC), nitric oxide (NO) and malondialdehyde (MDA). The present findings revealed a significant (p ≤ 0.05) increase in the values of CK, AST, LDH, glucose, lactate, TAG, urea, creatinine, phosphorus, MDA, TNF- α, IL6 and PGF2- α in diseased horses when compared with the control. Furthermore, the values of calcium, SOD, CAT, TAC, NO and GSH in diseased horses were significantly (p ≤ 0.05) lower than the control. The other examined parameters were not statistically significant. In conclusion, the examined pro-inflammatory cytokines were useful biomarkers for the diagnosis of Equine rhabdomyolysis (ER) in Arabian horses beside the old examined biomarkers. In the future, efforts should be made to confirm this in other breed. If this could be achieved, it would open up new perspectives in research fields dealing with ER.  相似文献   
10.
Ecological restoration of many arid zones is a pressing issue because of recurrent loss of plant cover. Here, we conducted a germination and growth study of three framework plant species, native to the Chihuahuan Desert in Northern Mexico, to optimize the establishment for arid zone restoration. The plant species were Zinnia grandiflora Nutt., Menodora scabra A. Gray, and Yucca elata (Engelm.) Engelm, which were selected for their potential for restoration as drought tolerant species. We evaluated seed germination, survival, and biomass allocation of seedlings under four (high, medium, low, and very low) simulated rainfall sequences as irrigation treatments. Rainfall sequences were obtained from a previous study that considered 35?years of precipitation records. Each sequence is accounted for 20% of probability of a wet, normal, low, or very low year in terms of precipitation occurring in the study area. Germination was conducted in controlled greenhouse conditions and seeding was done in pots containing soil mix. Sequences produced soil moisture fluctuations in which germination percent was higher for M. scabra (88%) and Z. grandiflora (31%) on the high sequence compared to the other sequences. Survival at the end of the treatments was above 80% of all the three species, and seedlings allocated more aboveground biomass as the moisture increased and more belowground biomass as moisture decreased. Implications under our study conditions include that germination of Y. elata would not be negatively affected by low soil moisture, and the best germinative results for Z. grandiflora and M. scabra would be achieved under higher soil moisture.  相似文献   
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