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排序方式: 共有1071条查询结果,搜索用时 15 毫秒
1.
Maria Antonia Machado Barbosa Kacilda Naomi Kuki Pedro Santos Peno Bengala Emilly dos Santos Pereira Angélica Fátima de Barros Sebastián Giraldo Montoya Leonardo Duarte Pimentel 《Journal of Agronomy and Crop Science》2020,206(2):263-276
Environmental conditions influence phenology and physiological processes of plants. It is common for maize and sorghum to be sown at two different periods: the first cropping (spring/summer) and the second cropping (autumn/winter). The phenological cycle of these crops varies greatly according to the planting season, and it is necessary to characterize the growth and development to facilitate the selection of the species best adapted to the environment. The aim of this study was to characterize phenological phases and physiological parameters in sorghum and maize plants as a function of environmental conditions from the first cropping and second cropping periods. Two parallel experiments were conducted with both crops. The phenological characterization was based on growth analyses (plant height, leaf area and photoassimilate partitioning) and gas exchange evaluations (net assimilation rate, stomatal conductance, transpiration and water-use efficiency). It was found that the vegetative stage (VS) for sorghum and maize plants was 7 and 21 days, respectively, longer when cultivated during the second cropping. In the first cropping, the plants were taller than in the second cropping, regardless of the crop. The stomatal conductance of sorghum plants fluctuated in the second cropping during the development period, while maize plants showed decreasing linear behaviour. Water-use efficiency in sorghum plants was higher during the second cropping compared with the first cropping. In maize plants, in the second cropping, the water-use efficiency showed a slight variation in relation to the first cropping. It was concluded that the environmental conditions as degree-days, temperature, photoperiod and pluvial precipitation influence the phenology and physiology of both crops during the first and the second cropping periods, specifically cycle duration, plant height, leaf area, net assimilation rate, stomatal conductance and water-use efficiency, indicating that both crops respond differentially to environmental changes during the growing season. 相似文献
2.
The effect of true milk use in the diet of Spanish Brown Swiss male calves on animal performance, carcass and meat quality, and fatty acids composition was studied. In experiment 1, the effect of milk intake [ad libitum continuous (ADLIB) feed vs. restricted 0.7 during 75 days followed by ad libitum feed (RESTR)] and slaughter endpoint (225 kg vs. 5 month) were studied. In experiment 2, ad libitum concentrate feeding [grain-fed (GF)] was compared with milk supplementation until slaughter [milk-fed (MF)] in calves slaughtered at 345 kg. As regards to milk intake, carcass weight and degree of fatness were higher in the ADLIB group (P<0.05). The RESTR group revealed a higher percentage of saturated fatty acids (P<0.05). In experiment 2, the MF group exhibited a higher fat percentage (P<0.05), lower press and cooking losses (P<0.05), and higher scores for tenderness and juiciness (P<0.05) than the GF group. The percentage of saturated fatty acids was higher in the MF group (P<0.05). The results suggest that true milk use in veal production could be an advantageous alternative in terms on production costs, animal performance, and carcass and meat quality. 相似文献
3.
Anahi S. Vieira Priscila S. Pinto Walter Lilenbaum 《Tropical animal health and production》2018,50(2):229-238
Leptospirosis is a bacterial systemic infection which affects domestic animals and wildlife, as well as humans. Many wild animals act as reservoirs of leptospires. Nevertheless, the real role of wildlife animals as source of infection to livestock and humans, as well as the most important reservoirs and leptospiral strains remains unclear. This systematic review assesses the available data about wildlife and their biomes in Latin America, concerning to leptospiral infection. In addition, we discuss the development of the research on leptospirosis in wildlife in this region. After the application of exclusion criteria, 79 papers were analyzed, comprising 186 species, 122 genus, 53 families, and 19 orders from four classes. Mammals were the most studied class, followed by Amphibian, Reptile, and Aves. The Icterohaemorrhagiae serogroup was predominant in most biomes and many orders. A small number of antigens detected the majority of seroreactive animals of each class, and a smaller panel may be used at microscopic agglutination test. Further studies must always consider edaphoclimatic conditions besides only host class or species, in order to obtain a broader understanding of the wild epidemiological cycle of leptospirosis in the region. In conclusion, direct and indirect evidences demonstrate that leptospirosis is largely widespread among wildlife in all biomes of Latin America. Moreover, more research on the role of wildlife on the epidemiology of leptospirosis and its impact on livestock and public health are required, particularly focusing on direct detection of the agent. 相似文献
4.
Paula de Aguiar Silva Gleidson Giordano Pinto de Carvalho Aureliano José Vieira Pires Stefanie Alvarenga Santos Douglas dos Santos Pina Robério Rodrigues Silva Carlindo Santos Rodrigues Luis Henrique Almeida de Matos Carlos Emanuel Eiras Daiane Novais-Eiras Wilson Souza Nunes 《Tropical animal health and production》2018,50(4):721-726
In this study, we evaluated the effects of including cassava wastewater in the diet on the feeding behavior of feedlot lambs in 35 male uncastrated Santa Inês × Dorper crossbred lambs at an approximate age of 3 months, with an average live weight of 20.0?±?3.4 kg. Diets were formulated with hay of cassava shoots (roughage) and a concentrate based on corn and soybean, with a roughage:concentrate ratio of 50:50, plus inclusion of cassava wastewater at the levels of 0, 12, 24, 36, or 48 g/kg of the total diet. Feeding behavior was evaluated between the 46th and 52nd days of the experiment. Increasing cassava wastewater levels in the diet reduced (P?<?0.05) the intakes (kg/day) of dry matter and neutral detergent fiber as well as the efficiency of rumination (g/cud and g/h) of dry matter and neutral detergent fiber. The other behavioral parameters were not affected by wastewater inclusion in the diet. Therefore, the inclusion of up to 48 g/kg of cassava wastewater on fresh matter of diets is not recommended for feedlot lambs. 相似文献
5.
Alberto J. P. Nunes Hassan Sabry‐Neto Severino Oliveira‐Neto Lena Burri 《Journal of the World Aquaculture Society》2019,50(6):1048-1063
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
6.
Effect of Stocking Density on Growth,Survival, and Condition of the Mexican Cichlid Cichlasoma beani
Edgar A. Aragon‐Flores Edna F. Valdez‐Hernandez Leonardo Martinez‐Cardenas Maria R. Castaeda‐Chavez Alfonso A. Gonzales‐Diaz Miriam Soria‐Barreto Javier M. J. Ruiz‐Velazco Emilio Pea‐Messina 《Journal of the World Aquaculture Society》2014,45(4):447-453
The Mexican cichlid Cichlasoma beani is currently exploited regionally as food and can be commercialized in the aquarium trade. Natural populations of C. beani may already be negatively affected by anthropogenic alteration of the areas in which it is distributed. The aim of the present study was to examine the effect on growth, survival, and condition of C. beani cultured in three stocking densities: three (D3), six (D6), and nine (D9) fish per each 40 L tank. At the end of a 6‐wk trial the fish cultured in D3 were longer, heavier, and grew faster than the rest of the treatments but their survival was the lowest compared to D6 and D9. The mortalities were caused by a strong aggressive behavior in D3. 相似文献
7.
Mariarita Romanucci Paolo E. Crisi Maria Veronica Giordano Morena Di Tommaso Francesco Simeoni Leonardo Della Salda 《Journal of veterinary diagnostic investigation》2021,33(1):112
A 14-y-old spayed female Labrador Retriever was presented with an 8-mo history of chronic vomiting. Abdominal ultrasound and gastrointestinal endoscopy revealed a mass protruding into the gastric lumen, with cytologic features suggestive of sarcoma. A partial gastrectomy was performed; the gastric body and antrum were thickened, with a cerebriform appearance of the mucosal surface. Histologic examination revealed a submucosal neoplastic proliferation of fusiform cells variably arranged in irregular bundles and scattered whorls. Fusiform cells strongly reacted to antibodies against vimentin, S100, and neuron-specific enolase; glial fibrillary acidic protein was moderately and multifocally expressed. Pancytokeratin, KIT, α–smooth muscle actin, and desmin were nonreactive. Histologic and immunohistochemical findings suggested a diagnosis of gastric sarcoma with features referable to a non-GIST (gastrointestinal stromal tumor), non–smooth muscle NIMT (non-angiogenic, non-lymphogenic intestinal mesenchymal tumor). The overlying gastric mucosa was thickened by elongated and dilated gastric glands, predominantly lined by intensely periodic acid-Schiff–stained mucous cells. This altered mucosal architecture was suggestive of Ménétrier-like disease. Although this disease has been hypothesized to predispose to gastric adenocarcinoma in dogs, an association with gastric sarcoma has not been documented previously in the veterinary literature, to our knowledge. 相似文献
8.
André Guimarães Maciel e Silva Suely Cristina Gomes de Lima Pedro Danilo de Oliveira Michel dos Santos Moraes Célia Maria Costa Guimarães Jamile Andréa Rodrigues da Silva Alexandre Rossetto Garcia Benjamim de Souza Nahúm Lilaine de Sousa Neres Gerlane Nunes Noronha José de Brito Lourenço Júnior 《Animal Science Journal》2021,92(1):e13576
The objective was to evaluate the effect of concentrate supplementation using by-products of the Amazonian industry on milk production, milk composition, and milk fatty acid profile of dairy buffaloes. Twelve lactating buffaloes (544.5 ± 35.6 kg, 6.4 ± 2.2 years old, 59 ± 6 days in milk) were allotted in a pasture of Mombaça grass and managed under rotational grazing (4 days occupancy/28 days rest). A 3 × 3 Latin square was adopted, and each animal alternately received three supplementary treatments based on corn bran + soybean meal or cupuaçu cake or murumuru cake for 21 days per treatment. Murumuru cake increased the levels of lauric acid and myristic acid in the milk (p < 0.05). Murumuru cake reduced the unsaturated fatty acid contents in the milk compared with animals fed control diet or cupuaçu cake (24.27% vs. 25.24% vs. 25.08%). The n-6/n-3 ratio was 2.6, 1.97, and 2.0 in the control, cupuaçu, and murumuru groups, respectively. Based on this parameter, cakes made from cupuaçu as well as murumuru could be considered to be adequate for inclusion in dairy water buffalo feed. However, the murumuru cake addition requires some caution because its use induces the secretion of higher levels of lauric and myristic fatty acids that are related to human cardiovascular disease. 相似文献
9.
Composition and fatty acid profile of milk from cows supplemented with pressed oilseed cake
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Ronaldo Lopes Oliveira Severino Gonzaga Neto Francisco Helton Sa de Lima Ariosvaldo Nunes de Medeiros Leilson Rocha Bezerra Elzania Sales Pereira Adriana Regina Bagaldo Caius Barcellos de Pellegrini Braulio Rocha Correia 《Animal Science Journal》2016,87(10):1225-1232
This study compared the productive and nutritional parameters of milk from crossbred lactating cows managed on Panicum maximum Jacq. cv. Tanzania and with a diet supplemented with different pressed oilseed cakes. The supplements used were as follows: peanut cake, sunflower cake and palm kernel cake for replacement of soybean meal. Sixteen cows with an average weight of 544 ± 57 kg and producing 8 ± 1.4 L of milk per day were used in this study. The animals were randomly assigned to the treatments according to a Latin square design repeated over time, with four treatments, 16 animals and four experimental periods. Supplementation of the diet with peanut cake, sunflower cake and palm kernel cake compared with soybean meal in the diet of cows did not affect the average daily production or composition of the milk. The palm kernel cake promoted an increase in lauric fatty acids (C12:0) and palmitoleic acids (C16:1) (5.02 and 1.65%, respectively) compared with peanut cake and sunflower cake (4.13 and 4.01%, respectively). The levels of oleic fatty acids (C18:1) were higher for the sunflower cake and palm kernel cake supplements (26.01 and 25.01%, respectively) compared with peanut cake (23.11%). The replacement of soybean meal with sunflower cake and palm kernel cake improved the nutritional quality of the milk, with lower concentrations of saturated fatty acids and higher concentrations of unsaturated fatty acids, without compromising the production or nutritional composition of the milk. © 2015 Japanese Society of Animal Science 相似文献