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排序方式: 共有477条查询结果,搜索用时 15 毫秒
1.
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
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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
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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
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de Ramos Eduarda Kalena Kirsch Pazdiora Paulo Cesar Dallagnol Leandro José de Souza Mayara Rodrigues de Araujo Filho Jeronimo Vieira 《植物病害和植物保护杂志》2023,130(1):211-214
Journal of Plant Diseases and Protection - Tobacco (Nicotiana tabacum L.) is one of the major nonfood crops in the Southern of Brazil. During 2019/2020 and 2020/2021 crop seasons, Root Knot... 相似文献
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Dennis N. Lozada R. Esten Mason Md Ali Babar Brett F. Carver Gina-Brown Guedira Keith Merrill Maria Nelly Arguello Andrea Acuna Lucas Vieira Amanda Holder Christopher Addison David E. Moon Randal G. Miller Susanne Dreisigacker 《Euphytica》2017,213(9):222
Genome-wide association studies (GWAS) are useful to facilitate crop improvement via enhanced knowledge of marker-trait associations (MTA). A GWAS for grain yield (GY), yield components, and agronomic traits was conducted using a diverse panel of 239 soft red winter wheat (Triticum aestivum) genotypes evaluated across two growing seasons and eight site-years. Analysis of variance showed significant environment, genotype, and genotype-by-environment effects for GY and yield components. Narrow sense heritability of GY (h 2 = 0.48) was moderate compared to other traits including plant height (h 2 = 0.81) and kernel weight (h 2 = 0.77). There were 112 significant MTA (p < 0.0005) detected for eight measured traits using compressed mixed linear models and 5715 single nucleotide polymorphism markers. MTA for GY and agronomic traits coincided with previously reported QTL for winter and spring wheat. Highly significant MTA for GY showed an overall negative allelic effect for the minor allele, indicating selection against these alleles by breeders. Markers associated with multiple traits observed on chromosomes 1A, 2D, 3B, and 4B with positive minor effects serve as potential targets for marker assisted breeding to select for improvement of GY and related traits. Following marker validation, these multi-trait loci have the potential to be utilized for MAS to improve GY and adaptation of soft red winter wheat. 相似文献
10.
Alyce Raiana Monteiro dos Santos Lívia Vieira de Barros Matheus Lima Côrrea Abreu Bruno C. Pedreira 《Grass and Forage Science》2020,75(3):339-350
The addition of protein supplementation in a silvopastoral system can contribute to improved forage intake and digestibility. Our objective was to evaluate in vitro ruminal parameters, digestibility and gas production of Marandu palisadegrass [Urochloa brizantha (Hochst. ex A. Rich.) R. D. Webster] in a silvopastoral system and compare this to parameters obtained from diets with protein supplementation. Forage was sampled during the growing season (November to April) in 2016/17 and 2017/18. In vitro incubation treatments consisted of four levels of protein supplement (20% of crude protein; CP) in the diet (0.1, 0.2, 0.3 and 0.4 g/kg of body weight). The neutral detergent fibre, acid detergent fibre and indigestible neutral detergent fibre concentrations were highest in the first year. In the second year, CP concentration was 21% greater than in the first year. There was a linear increase for digestion rate, a quadratic effect for lag time and a linear decrease for average digestion time as supplementation levels were increased. The least lag time and digestion time occurred in the second year. There was no supplementation effect on ruminal pH, acetate and butyrate concentrations. Second-year in vitro dry matter digestibility (IVDMD) was greater than in the first year. Increases in supplementation levels linearly enhanced IVDMD and reduced methane (CH4) production. The inclusion of a protein supplement contributed to reduced CH4 and increased volatile fatty acids production; therefore, we recommended the supplement inclusion of >0.28 g/kg of BW for animals grazing in well-managed palisadegrass pastures. 相似文献