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991.
992.
Marcelo Machado Severo Luis Fernando Glasenapp de Menezes Fernando Kuss Wagner Paris Ruan Crespi Haveroth Guilherme B. Souto Ariadny Cristhina Sanches 《Animal Science Journal》2023,94(1):e13803
The aim was to evaluate the effect of different rates of weight gain during the backgrounding on animal performance and carcass and meat characteristics of steers finished in feedlots. Thirty-six Angus steers, 12 ± 2 months of age, were backgrounded during 91 days on Aruana grass pasture (Panicum maximum cv. Aruana) managed under different stocking rates to achieve three different weight gains: HIGH ADG (average daily gain)—no feed restriction (ADG = 0.846 kg); MEDIUM ADG—moderate feed restriction (ADG = 0.456 kg); and LOW ADG—high feed restriction (ADG = 0.154 kg). To ensure the difference in ADG, we offered 0.7% live weight of concentrate feed in the HIGH treatment and a better forage supply in the MEDIUM treatment. After the backgrounding, the animals were finished in feedlot. There was no effect of the previous performance on the animals' performance in the feedlot. The LOW presented higher weight (218.9 vs. 207.9 kg) and hot (54.0% vs. 51.3%) and cold (53.5% vs. 50.5%) carcass yield than the MEDIUM, besides presenting meat with less cooking losses (15.0% vs. 18.2%), marbling (7 vs. 4.0 points), palatability (7.1 vs. 6.3 points), juiciness (7.2 vs. 6.4 points), tenderness (7.1 vs. 6.3 points), and lower shear force (5.78 vs. 8.75 kg) than HIGH. LOW ADG steers stay longer in the finishing phase but presented in general better quality carcass and meat than those with MEDIUM or HIGH during the backgrounding. 相似文献
993.
Tiago Garcia da Cunha Ronnie Von dos Santos Veloso Matheus Miller Mesquita de Araújo Luciano Gabriel Tavares Luiz Fernando Borges Ribeiro Gislaine Pacheco Tormen Diogo Santos Campos Marcelo Coutinho Picanço Everaldo Antônio Lopes Renata Ramos Pereira Marcus Alvarenga Soares Ricardo Siqueira da Silva 《Pest management science》2023,79(7):2325-2337
994.
Méndez-Hermida F Gómez-Couso H Romero-Suances R Ares-Mazás E 《Veterinary parasitology》2007,144(1-2):153-156
A total of 437 faecal samples from wild otter (Lutra lutra) were collected from 161 sites in Galicia (northwest Spain) and were analysed by a direct immunofluorescence antibody test (IFAT). Cryptosporidium sp. oocysts and Giardia sp. cysts were detected in 17 (3.9%) and 30 (6.8%) samples, respectively. The results demonstrate that otters may contribute to the contamination of watercourses, although further studies are required to establish which species or genotypes of Cryptosporidium and Giardia infect these animals and also the significance in terms of public health. 相似文献
995.
Zuckermann FA Garcia EA Luque ID Christopher-Hennings J Doster A Brito M Osorio F 《Veterinary microbiology》2007,123(1-3):69-85
The efficacy of two different types of commercial vaccines against PRRSV (Euro-type) was evaluated based on clinical parameters upon challenge as well as post-challenge virological profiles (viremia and viral load in tissues upon necropsy, measured in both cases by quantitative real time PCR). In an attempt to establish correlates of protective immunity, two commonly proposed parameters predictive of immunity were measured: (1) serologic responses (ELISA and neutralizing antibodies), (2) frequency of gamma interferon-producing cells in peripheral blood mononuclear cell fraction. The vaccines compared consisted of two commercially available products that are regularly marketed in Spain: one modified live virus and one killed vaccine. The efficacy assay was carried out by vaccinating twice 3 weeks apart groups of 5 and-a-half month-old female swine and then challenging them with a European type 1 PRRSV strain (Lelystad). The results obtained indicate that the modified live virus vaccine was the only type of vaccine capable of establishing protective immunity, as measured by viral load in blood and tissues. The killed vaccine, in spite of this product evoking a spontaneous interferon-gamma response and post-challenge titers of virus-neutralizing antibody, evoked no measurable protective immunity. In the case of the modified live vaccine, the protection exhibited did not appear to be based on humoral but rather on cell-mediated immunity. 相似文献
996.
Heat stress (HS) is a major threat to current and future crop production. Crop improvement for HS tolerance is a major tool for dealing with HS and crop wild relatives (CWR) offer the greatest variability for such improvement. Here, we evaluated the HS tolerance on four reproductive traits in cultivated and wild sunflower and tested for local adaptation to HS within the wild germplasm. Three cultivars and 23 wild populations (from native and invasive ranges) were grown in field experiments for 2 years. Flowering heads were covered with white (control) and black (HS) paper bags during seven consecutive days. Additionally, biogeographic tools were used to test for local adaptation. HS increased air temperature on black bags compared to the white ones by 9.4 °C on average and strongly decreased seed number and yield with smaller effects on head diameter and seed weight. We found large variability for HS tolerance, mainly in seed number and yield. The invasive group outperformed the cultivated and native groups in both years. Biogeographic analysis reveals a clinal variation in HS tolerance, populations from wetter (but not from warmer) environments were more tolerant to HS. In addition, the positive correlation observed between reproductive traits under control conditions and HS tolerance helps to explain the better performance of the invasive populations. We proposed the use of invasive populations for future sunflower improvements in HS tolerance and the adoption of biogeographic tools in another CWR species to identify HS tolerant populations. 相似文献
997.
Pena Lorena Carolina Jung Luiz Fernando Savi Daiani Cristina Servienski André Aluizio Rodrigo Goulin Eduardo Henrique Galli-Terasawa Lygia Vitória de Noronha Sales Maia Beatriz Helena Lameiro Annies Vinicius Franco Célia Regina Cavichiolo Glienke Chirlei Kava Vanessa 《植物病害和植物保护杂志》2017,124(4):349-360
Journal of Plant Diseases and Protection - The citrus industry is among the most important worldwide, but citrus plants are affected by a large number of diseases, such as Citrus Black Spot (CBS),... 相似文献
998.
Retrospective evaluation of 155 adult equids and 21 foals with tetanus from Western,Northern, and Central Europe (2000–2014). Part 2: Prognostic assessment 下载免费PDF全文
Gaby van Galen DVM PhD DECEIM Joke Rijckaert DVM Tim Mair BVSc PhD DECEIM Helene Amory DVM PhD DECEIM Lara Armengou DVM PhD DECEIM Barbora Bezdekova DVM PhD DECEIM Inge Durie DVM DECEIM Rikke Findshøj Delany DVM Nathalie Fouché DVM Laura Haley MVB Michael Hewetson BVSc DECEIM Rene van den Hoven DVM PhD DECEIM Anna Kendall DVM DECEIM Fernando Malalana DVM DECEIM MRCVS Jessika Muller Cavalleri DVM DECEIM PhD Tresemiek Picavet DVM DECEIM Katja Roscher DVM DECEIM Denis Verwilghen DVM PhD DECVS Cornélie Westermann DVM PhD DECEIM Claude Saegerman DVM PhD DECVPH 《Journal of Veterinary Emergency and Critical Care》2017,27(6):697-706
999.
Jorge Cornejo Jaime Tapia Fernando Guerra Marco Yáñez Ricardo Baettig Jorge Guajardo Eduardo Alarcón Gladys Vidal 《Water, air, and soil pollution》2017,228(6):212
Heavy metal contamination causes significant environmental problems around the world and poses a threat to human health. Poplar hybrids present features for potential uses in phytoremediation systems in areas with heavy metal contamination. The purpose of this study was to assess the copper (Cu) accumulation level in five poplar inter-species hybrids [(Populus trichocarpa × Populus deltoides) × P. deltoides; P. deltoides × Populus nigra; P. trichocarpa × Populus maximowiczii; P. trichocarpa × P. nigra; and (P. trichocarpa × P. deltoides) × (P. trichocarpa × P. deltoides)] grown in a hydroponic system. The treatments entailed the application of low and high doses of Cu of 8.0 and 16.0 μM, respectively. Cu accumulation was observed in roots, stems, and leaves, which was determined using flame atomic absorption spectroscopy, prior acid digestion of each sample. The methodology was validated according to certified reference material (Cypress BIMEP 432). Significant differences in Cu accumulation were found among genotypes for both roots and leaves, but not for stems. In roots, the genotype P. deltoides × P. nigra had a Cu accumulation level of 169.8% higher than the average accumulation found in the other genotypes. The (P. trichocarpa × P. deltoides) × P. deltoides hybrid showed the least Cu accumulation in leaves. The results of this study can potentially be used for proper crossovers and hybrids selection within the genus Populus for phytoremediation of Cu contaminated land. 相似文献