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991.
Julimar do Sacramento Ribeiro Luana Lira Santos Dorgival Morais de Lima Júnior Tobyas Maia de Albuquerque Mariz Márcio Machado Ladeira Paulo Sérgio de Azevedo Carolyny Batista Lima Maria Josilaine Matos dos Santos Silva 《Tropical animal health and production》2017,49(5):995-1000
The effect of the replacement of corn silage with spineless cactus associated with Tifton 85 hay or sugarcane bagasse was evaluated on the performance, body weight components and sheep meat quality. Twenty-one Santa Inês male sheep with initial body weight of 22.9 ± 2.9 kg were used. They were confined in individual stalls for 74 days receiving the following diets: corn silage + concentrate (CS); spineless cactus + Tifton 85 hay + concentrate (TH); spineless cactus + sugarcane bagasse + concentrate (SB). After the feedlot period, the animals were slaughtered and their body components were weighed and sampled. Data were submitted to Tukey’s test at 5% probability. The average daily gain (0.25 vs 0.14 kg), cold carcass weight (13.3 vs 13.7 kg), loin muscularity (0.6 vs 0.4 kg) and liver weight (0.7 vs. 0.5 kg) were higher (P < 0.05) for the TH diet when compared to that for the CS. The physical-chemical parameters of meat were not influenced (P > 0.05) by the treatments and presented about 20.1% of crude protein, 6.1% of crude fat and shear force of 2.0 kgf/cm2. In complete diets for sheep, Tifton 85 hay associated with spineless cactus provides greater weight gain, cold carcass muscularity and organ weight when compared to those for animals fed with corn silage as exclusive roughage. Sugarcane bagasse associated with spineless cactus may replace corn silage in complete diets for sheep. 相似文献
992.
993.
Richard L. Mulvaney Rafael Otto Kelsey L. Griesheim Kai Su Paulo Cesar Ocheuze Trivelin 《Communications in Soil Science and Plant Analysis》2016,47(13-14):1701-1708
Aerobic incubations to estimate net nitrogen (N) mineralization typically involve periodic leaching of soil with 0.01 M calcium chloride (CaCl2), so as to remove mineral N that would otherwise be subject to immobilization. A study was conducted to evaluate the accuracy of leaching for analysis of exchangeable ammonium (NH4+)-N and nitrate + nitrite (NO3?+ NO2–)-N, relative to conventional extractions using 2 M potassium chloride (KCl). Ten air-dried soils were used, five each from Illinois and Brazil, that had been amended with NH4+-N (1 g kg?1) and NO3–-N (0.6 g kg?1). Both methods were in good agreement for inorganic N analysis of the Brazilian Oxisols, whereas leaching was significantly lower by 12–48% in recovering exchangeable NH4+-N from Illinois Alfisols, Mollisols, and Histosols. The potential for underestimating net N mineralization was confirmed by a 12-wk incubation experiment showing 9–86% of mineral N recoveries from three temperate soils as exchangeable NH4+. 相似文献
994.
995.
Tancredo Augusto Feitosa de Souza Andrea Fernandes Rodrígues Luciano Façanha Marques 《Russian Agricultural Sciences》2016,42(1):11-16
The influence of long-term fertilization on plant development and soil properties was investigated. Soil samples were taken from a long-term field experiment which was conducted for 5 years to explore the effect of three treatments: control (non-fertilization), conventional (mineral fertilizers—NPK), and alternative (organic fertilizers—farmyard manure). The highest values of plant yield and soil properties were found in the alternative fertilization system after the thirty year of its utilization. Conventional fertilization showed positive effects until the second year of its utilization where enhanced soil fertility (total nitrogen and available phosphorous content) and plant development (plant yield, plant dry biomass, plant phosphorous concentration, and plant nitrogen concentration). After the thirty year the conventional fertilization system showed lower values for these studied variables compared to alternative fertilization system. Our findings suggest that inputs of organic matter source can change positively the wheat growth and soil fertility, and these results highlight the importance of considering the long-term effect of mineral and organic fertilizers on these variables. 相似文献
996.
Danielle A. D. Nunes Emanuela F. Gama-Rodrigues Patrícia A. B. Barreto Antonio C. Gama-Rodrigues Paulo H. M. Monroe 《林业研究》2016,27(1):91-99
Use of legume trees can improve soil quality in degraded pastures. The aim of this study was to characterize C and N mineralization kinetics and estimate the potentially mineralizable C and N in soil under Mimosa caesalpiniifolia Benth. and Acacia auriculiformis A. Cunn.ex Benth. secondary forest and pasture in red-yellow latosols in southeast Brazil. We conducted a laboratory aerobic incubation experiment using a completely randomized design of four replicates and four types of plant cover using a modified version of the Stanford and Smith technique(1972) to study C and N mineralization potential.Potentially mineralizable N(N_o) ranged from 135 to170 mg kg-~(1). The predominant form of mineral N for all types of plant cover was N-NO_3~-. M. caesalpiniifolia was the only species that had a positive influence on N mineralization. Neither of the legumes influenced C mineralization in pasture or secondary forest. The model of N mineralization corresponded to a sigmoidal curve while C mineralization corresponded to an exponential curve,revealing that the N and C mineralization processes were distinct. N mineralized by M. caesalpiniifolia(216 kg of N ha~(-1)) was adequate to meet the N requirement for a livestock-forest system. 相似文献
997.
Kamila Gravena Rita de Cássia de Lima Sampaio Deborah Penteado Martins Dias Paulo Aléscio Canola Juliana Regina Peiró José Corrêa de Lacerda-Neto 《Journal of Equine Veterinary Science》2012
The purpose of this study was to evaluate the integrity of dermal and epidermal tissues collected by dorsal transmural access. Eight healthy adult horses were subjected to two biopsies of the right hoof, with a 24-hour interval. To ensure hoof integrity, a radiographic evaluation with dorsopalmar and lateromedial positions was performed. The animals were sedated, and the pedal tissue was collected from two sites that were 2 cm distal to the coronary band. For each biopsy, the hoof wall was perforated using an aluminum oxide drill bit, 4.8 mm in diameter that was connected to a drilling machine, yielding a hole of approximately 9.0 mm. The perforation procedure was performed slowly in the stratum medium until 1 mm of it remained, which was determined by evaluating the movement in response to pressure applied with a Halstead forceps. Laminar deep incisions were performed with a number 11 scalpel blade until the distal phalanx was reached. The laminar tissue was then removed using a Frahm scaler. A cuboid laminar sample measuring approximately 5 mm at the base and 7 mm in height was obtained. The samples were suitable for analysis by histology and transmission electron microscopy showing that the ends of the secondary epidermal laminae were round, the basement membrane was intact between the secondary epidermal laminae and secondary dermal laminae, and the ultrastructural analysis of the cells showed their structural integrity. 相似文献
998.
Lobo L Pinheiro-Vieira A Gomes JL Canada N Ribeiro L Costa PD Oliveira P Bussadori C 《Journal of the American Animal Hospital Association》2012,48(1):54-59
A 1 yr old male Estrela mountain dog was evaluated as a part of a screening program for dilated cardiomyopathy. The dog came from a family with a history of dilated cardiomyopathy but was asymptomatic. Occult dilated cardiomyopathy and sino-atrial dysfunction were diagnosed based on echocardiography and electrocardiography. These two disorders may be associated given that related dogs have been diagnosed with the same disorders. The dog has remained asymptomatic for 4 years following initial evaluation. 相似文献
999.
Alessandra Marnie Martins Gomes de Castro Cintia Maria Favero Cintia Manzatto Baldin Mauro Borba Fernando Gomes de Castro Júnior Simone Miyashiro José Carlos de Moura Ricardo Arruda Dias Paulo Eduardo Brand?o Leonardo José Richtzenhain 《Canadian journal of veterinary research》2012,76(3):174-179
Torque teno sus virus (TTSuV) is emergent in swine herds. Recent studies have shown an increased frequency of TTSuV2 in Porcine circovirus type 2 (PCV2)-associated diseases (PCVAD), which are endemic in many swine-producing countries, including Brazil. Coinfection with several other viral and bacterial agents results in an increased incidence of more severe PCVAD. Given the limited information on TTSuV and PCV2 coinfection, especially in Brazilian swine herds, this study made a preliminary estimation of the occurrence of coinfection in swine herds by testing samples from different categories. Between 2008 and 2009, 111 samples of feces and 23 serum samples from 5 swine herds were tested for PCV2 and TTSuVs and the results analyzed for associations between these agents. No significant differences in coinfection frequency were observed for PCV2 + TTSuV1 or for PCV2 + TTSuV2 between nursery piglets (P = 0.730), growing pigs (P = 0.331), or sows (P = 0.472). However, a significant difference was observed for PCV2 + TTSuV1 + TTSuV2 between nursery piglets and growing pigs (P = 0.004; Fisher’s exact test). Phylogenetic studies agreed with the grouping of TTSuV1 and TTSuV2 into 2 different clades, with no distinct pattern of clustering of these isolates with the animal categories. 相似文献