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51.
Vladimir Vecerek Josef Kamenik Eva Voslarova Lenka Vecerkova Zuzana Machovcova Martina Volfova Jarmila Konvalinova 《Animal Science Journal》2020,91(1)
The difference in the frequency of the occurrence of reflexes/reactions in 355 cows (average weight 505.5 ± 7.9 kg) and 262 bulls (average weight 735.6 ± 8.4 kg) following stunning with a Matador SS 3,000 B trigger‐activated captive bolt gun (Termet) was determined. The stun shot more than 2 cm from the ideal position was found in 79.6% of animals. Vocalization, corneal reflex, rhythmic breathing, blinking, eyeball rotation and the absence of tongue protrusion occurred more frequently in bulls (p < .05). Spontaneous limb movements and nystagmus occurred more frequently in cows (p < .05). No difference between bulls and cows was determined in the occurrence of a response to painful stimuli or attempts to regain normal posture. No dependency was determined between the frequency of the occurrence of a reflex/reaction and the distance of the stun shot from the ideal point on the skull for any of the monitored signs. This study shows that the occurrence of reflexes/reactions following the stunning of cattle with a captive bolt is not only dependent on the position of the shot if placed within a 9 cm radius from the ideal point on the cattle skull. 相似文献
52.
Eva Johansson 《Euphytica》2002,126(1):143-149
Variation in falling number, amylase activities, protein concentration and composition were investigated in two wheat cultivars
grown in Sweden over two seasons, in four locations, with four N fertilizer rates, with and without fungicide treatment. The
results showed that;
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
• | Tarso had higher falling number, amylase activities, protein concentration and amount of most protein components compared to Kosack. |
• | The environment (year, location, N rate and fungicide treatment) influenced falling number, alpha amylase activities, and protein concentration and composition. |
• | Two processes were related to low falling numbers; late maturity leading to poor starch and protein quality and excessive rains leading to break-down of starch and proteins. |
• | Poor starch and protein properties influenced the bread-making quality to a higher extent than break-down of starch and proteins. |
53.
Little is known about nutrient fluxes and nutrient‐use efficiencies in urban and peri‐urban agriculture (UPA) of rapidly expanding cities in developing countries. Therefore, horizontal flows of carbon (C), nitrogen (N), phosphorus (P), and potassium (K) as well as leaching losses of mineral N and P were measured over 2 years in three representative agricultural production systems of Kabul. These comprised 21 gardens and 18 fields dedicated to vegetable farming, cereal farming, and table‐grape production (vineyards). Across sites (fields and gardens) biennial inputs averaged 375 kg N ha–1, 155 kg P ha–1, 145 kg K ha–1, and 15 kg C ha–1 while with harvests 305 kg N ha–1, 40 kg P ha–1, 330 kg K ha–1, and 7 kg C ha–1 were removed. In vegetable gardens, biennial net balances were 80 kg N ha–1, 75 kg P ha–1, –205 kg K ha–1, and 4 kg C ha–1, whereas in cereal farming biennial horizontal balances amounted to –155 kg N ha–1, 20 kg P ha–1, –355 kg K ha–1, and 5 kg C ha–1. In vineyards, corresponding values were 295 kg N ha–1, 235 kg P ha–1, 5 kg K ha–1, and 3 kg C ha–1. Annual leaching losses in two selected vegetable gardens varied from 70 to 205 kg N ha–1 and from 5 to 10 kg P ha–1. Night soil and irrigation water were the major sources among the applied nutrient inputs in all studied farming systems, contributing on average 12% and 25% to total N, 22% and 12% to total P, 41% and 53% to total K, and 79% and 10% to total C, respectively. The results suggest that soils in extensive cereal fields are at risk of N and K depletion and in vegetable gardens of K depletion, while vineyards may be oversupplied with nutrients possibly contributing to groundwater contamination. This merits verification. 相似文献
54.
Scott HM Sorensen O Wu JT Chow EY Manninen K VanLeeuwen JA 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(10):981-991
A province-wide, cross-sectional seroprevalence and agroecological risk factor study of Mycobacterium avium subspecies paratuberculosis (MAP), Neospora caninum (NC), Bovine leukemia virus (BLV), and Bovine viral diarrhea virus (BVDv) genotypes 1 and 2 (BVDv1 and BVDv2) infection in dairy cattle herds in Alberta was conducted. Among adults, the seroprevalence of MAP, NC, and BLV was 9.1%, 18.5%, and 26.9%, respectively. For MAP, based on a herd test cutpoint of 2 or more seropositive cows, 58.8% of herds were infected. Herd-level seroprevalence for NC and BLV was 98.7% and 86.7%, respectively, based on a herd-test cutpoint of 1 seropositive cow. Among unvaccinated dairy heifers, the seroprevalence for BVDv1 and BVDv2 infection was 28.4% and 8.9%, respectively, while herd-level infection was 53.4% and 19.7%. Seroprevalence for MAP varied moderately by agroecological region, whereas that for NC, BLV, and BVDv1 and BVDv2 did not. For MAP, aridity and soil pH (correlated features of the region) were also important. 相似文献
55.
Eva VOSLAROVA Petr CHLOUPEK Jan CHLOUPEK Iveta BEDANOVA Vladimira PISTEKOVA Vladimir VECEREK 《Animal Science Journal》2011,82(4):601-606
Effects of different noise levels (70 or 80 dB) that broilers were exposed to during the entire fattening period and also the effect of the timing of the first exposure to intermittent noise in the course of fattening (day 1 vs. day 7) were monitored. After 7 days of exposure to intermittent noise, experimental chickens already showed a significant decrease in live body weight in comparison with the control group. The difference between the group exposed to intermittent noise at 70 dB and the group exposed to 80 dB levels was not statistically significant, although the mean live body weight of broilers in the latter was lower during the entire fattening period. The chickens exposed to intermittent noise from day 1 of age showed lower mean live weight throughout the fattening period compared to chickens exposed to the same level of intermittent noise only from day 7 of age, although at the end of fattening the difference was statistically significant only in chickens exposed to the higher level of intermittent noise (80 dB). 相似文献
56.
Background
In the last few years stud farms have experienced increasing problems with Parascaris equorum infections in foals despite intensive deworming programs. This has led to the question as to whether the anthelmintic drugs used against this parasite are failing. This study aimed to investigate the efficacy of ivermectin, fenbendazole and pyrantel on the faecal output of ascarid eggs of foals.Methods
A Faecal Egg Count Reduction Test (FECRT) was performed on nine large studs in Sweden. Anthelmintic drugs were given orally and faecal samples were examined for ascarid eggs on the day of deworming and 14 days later. Faecal Egg Count Reductions (FECRs) were calculated on arithmetic means of transformed individual FECRs and on arithmetic means of individual FECRs.Results
Seventy-nine (48%) out of a total of 165 foals sampled were positive for P. equorum eggs before deworming and 66 of these met the criteria for being used in the efficacy assessment. It was shown that there was no, or very low activity of ivermectin on the output of ascarid eggs in the majority of the foals, whereas for fenbendazole and pyrantel it was >90%.Conclusion
Ivermectin resistance was shown in 5 out of 6 farms. Therefore, ivermectin should not be the drug of choice in the control of P. equorum infections in foals. According to the results of this study, fenbendazole or pyrantel are still effective and should be used against this parasite. 相似文献57.
Dividing regions into manageable landscape units presents special problems in landscape ecology and land management. Ideally,
a landscape should be large enough to capture a broad range of vegetation, environmental and disturbance dynamics, but small
enough to be useful for focused management objectives. The purpose of this study was to determine the optimal landscape size
to summarize ecological processes for two large land areas in the southwestern United States. We used a vegetation and disturbance
dynamics model, LANDSUMv4, to simulate a set of nine scenarios involving systematically varied topography, map resolution,
and model parameterizations of fire size and fire frequency. Spatial input data were supplied by the LANDscape FIRE Management
Planning System (LANDFIRE) prototype project, an effort that will provide comprehensive and scientifically credible mid-scale
data to support the National Fire Plan. We analyzed output from 2,000 year simulations to determine the thresholds of landscape
condition based on the variability of burned area and dominant vegetation coverage. Results show that optimal landscape extent
using burned area variability is approximately 100 km2 depending on topography, map resolution, and model parameterization. Variability of dominant vegetation area is generally
higher and the optimal landscape sizes are larger in comparison to those features determined from burned area. Using the LANDFIRE
project as a case study, we determined landscape size and map resolution for a large mapping project, and showed that optimal
landscape size depends upon geographical, ecological, and management context.
This paper was written and prepared by U.S. Government employees on official time, and therefore is in the public domain and
not subject to copyright. The use of trade or firm names in this paper is for reader information and does not imply endorsement
by the U.S. Department of Agriculture of any product or service. 相似文献
58.
59.
60.
Díaz-Maroto MC Díaz-Maroto Hidalgo IJ Sánchez-Palomo E Pérez-Coello MS 《Journal of agricultural and food chemistry》2005,53(13):5385-5389
Volatile oil extracts of fennel seeds (Foeniculum vulgare Mill.) and thyme leaves (Thymus vulgaris L.) were obtained by simultaneous distillation-extraction (SDE) and supercritical fluid extraction (SFE) and analyzed by gas chromatography-mass spectrometry (GC-MS). In general, fennel oil extracted by SDE and SFE showed similar compositions, with trans-anethole, estragole, and fenchone as the main components. In contrast, thymol and p-cymene, the most abundant compounds in thyme leaves, showed big differences, with generally higher amounts of monoterpenes obtained by SDE. However, in this case, the differences between the extracts were higher. Key odorants of fennel seeds determined by gas chromatography-olfactometry (GC-O) showed similar patterns when applying SDE and SFE. trans-Anethole (anise, licorice), estragole (anise, licorice, sweet), fenchone (mint, camphor, warm), and 1-octen-3-ol (mushroom) were the most intense odor compounds detected in fennel extracts. Thymol and carvacrol, with oregano, thyme, and spicy notes, were identified as key compounds contributing to the aroma of thyme leaves. 相似文献