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11.
A surgically excised biopsy representing a subcutaneous mass on the left side of the neck from a 3-year-old female European hedgehog (Erinsceus europaeus) was presented. Spontaneous myxosarcoma was diagnosed based on histological, immunohistochemical, and ultrastructural characteristics. The neoplasm grossly consisted of a firm, pale, multilobulated mass with a characteristic clear gelatinous fluid. Histologically, the neoplasm was nonencapsulated and composed of pleomorphic stellate or spindle-shaped vimentin and periodic acid-Schiff-positive cells arranged in loose sheets and occasionally whorls. The neoplastic cells were suspended in Alcian blue-positive stroma and contained infrequent mitotic figures. Evidence of a viral etiology was not detected using electron microscopy and polymerase chain reaction. This is the first case report of a myxosarcoma in a captive European hedgehog.  相似文献   
12.
We isolated the rotifers Brachionus ibericus and Proales similis from the sediment of shrimp tanks and studied their individual demographic characters and competition between them at two food levels (0.25?×?106, 1.00?×?106 cells ml?1 of Nannochloropsis oculata at 25 °C) and salinities ranging from 10 to 30‰. Our hypothesis was that growth rates would be higher with increasing food levels and salinities. Observations were taken twice a day for life table studies and daily once for population growth experiments. Using survivorship and fecundity data, we derived various life history variables. Although the average life span (7.6?±?0.4 days) and gross reproductive rate (33.8?±?2.9 neonate female?1 day?1) of B. ibericus were higher than those of P. similis (average life span 5.4?±?0.6 days and gross reproductive rate 13.0?±?0.6 neonate female?1 day?1), the population growth experiments showed that P. similis had higher r values (0.32?±?0.005 day?1) than B. ibericus (0.23?±?0.002 day?1) at 1.0?×?106 cells ml?1 of N. oculata. The rotifer P. similis was more adversely affected due to the presence of B. ibericus than vice versa. The data are important for developing techniques for a large-scale culture of these rotifers as food in aquaculture.  相似文献   
13.
Plant Foods for Human Nutrition - In semiarid regions of Mexico, it is common to use the floristic richness of wild plants as food ingredients. Hence, flowers of Agave salmiana, Aloe vera,...  相似文献   
14.
Herpesviruses have been recognized in marine mammals, but their clinical relevance is not always easy to assess. A novel otarine herpesvirus-3 (OtHV3) was detected in a geriatric California sea lion (Zalophus californianus), and using a newly developed quantitative PCR assay paired with histology, OtHV3 was associated with esophageal ulcers and B cell lymphoblastic lymphoma in this animal. The prevalence and quantities of OtHV3 were then determined among buffy coats from 87 stranded and managed collection sea lions. Stranded sea lions had a higher prevalence of OtHV3 compared to managed collection sea lions (34.9% versus 12.5%; p = 0.04), and among the stranded sea lions, yearlings were most likely to be positive. Future epidemiological studies comparing the presence and viral loads of OtHV3 among a larger population of California sea lions with and without lymphoid neoplasia or esophageal ulcers would help elucidate the relevance of OtHV3-associated pathologies to these groups.  相似文献   
15.
The aim of this study was to develop a non‐invasive procedure to stimulate ejaculation in median and small lizards for semen collection. After semen collection, we applied a battery of tests to assess the motility (wave and progressive), viability (eosin–nigrosin stain), morphology (normal/abnormal), sperm concentration and ejaculate number, seminal volume and colour. We obtained this fluid from all males of the four species of sceloporine lizards (n = 30) and one species of Mexican horned lizards (n = 7). We found that semen from all males had a liquid‐like consistency and a milky‐white appearance. Ejaculate volume and sperm concentration varied among the males and the species studied. We also observed that although the mobility, viability and normal sperm morphology showed a wide variability, their average value in each species was high. We conclude that “genital papilla pressure” was an efficient and non‐invasive semen obtaining method for small‐ and medium‐sized lizards that does not imply damage to donors and could be used in other lizard species.  相似文献   
16.
Feed intake and digestibility were evaluated in sheep fed low quality Taiwan grass supplemented with Tithonia diversifolia. Four wether hair sheep were housed in metabolic cages and fed with either Control concentrate 20%, Tithonia 20, 35 or 50% in a Latin Square design. Adaptation and, feces and urine collection periods were 14 and 7 days, respectively. Feed intake was increased (P < 0.01) from 58.5 in control to 86.1 g/kg0.75 in sheep fed Tithonia. NDF intake and digestibility were affected by Tithonia level. Nitrogen intake increased linearly (P < 0.01) with increase in feces and urine excretion. N retention was similar (P > 0.1) among sheep fed Tithonia, but different (P < 0.05) from control. Inclusion of Tithonia foliage at 20% of the DM diet of hair sheep improved their intake of low quality Taiwan grass and nitrogen retention. Higher levels of Tithonia in the diet, however, increase nitrogen loss in feces and urine.  相似文献   
17.
Transmission patterns of Salmonella in a swine production unit were investigated by statistical analysis of the spatial distribution of isolates and the clustering of genotypes over a 12-week period. The study unit was a breeding-gestation building in a single-site farrow-to-finish swine production system. During the summer of 2003, 1746 pen floor samples were collected during 6 visits conducted at 2-week intervals. Genotyping was performed on the 107 Salmonella isolates obtained using repetitive sequence PCR (3 primers: REP, BOX, ERIC). Genetic similarity was evaluated by DNA fragment matching and hierarchical cluster analysis based on genetic similarities. For each visit, the distance at which spatial clustering of Salmonella isolates occurred was estimated using second order analyses. Significant spatial clustering of Salmonella up to a distance of 15.2m was identified for 4 of the 6 farm visits, those for which the prevalence of Salmonella was the highest. Cluster analysis of genetic similarities identified 4 groups of Salmonella isolates at the level of at least 85% similarity in rep-PCR fragment matching patterns. Genetic clusters were relatively homogeneous for time of visit, with each genetic cluster consisting of isolates from the same or temporally adjacent visits. The correlation between genetic similarity and spatial proximity between pairs of Salmonella isolates, and the correlation between these measures and differences in time of sampling, were evaluated using Mantel's r. There was a strong positive correlation (r=0.62, p<0.0001) between genetic distance and time of sampling, indicating evolution of the Salmonella population over time. For 4 of the 6 visits, a pattern of decreasing genetic similarity between isolates with increasing distance between sampling locations was apparent. However, when viewed over all 6 visits, Salmonella was concentrated in one area of the building and did not move in any specific direction. These results suggest that a particular genotype of Salmonella, if introduced in the breeding-gestation unit of a swine farm would evolve slowly over short time intervals; its spatial distribution would be limited primarily to adjacent or nearby pens. In this study spatial analysis (e.g., Ripley's K-function) and matrix correlation methods (e.g., Mantel's r) expanded upon cluster analysis of genotypic similarities to provide additional interpretable information regarding the spatial distances to which Salmonella is transmitted over time in swine production facilities.  相似文献   
18.
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