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31.
Manoel Eduardo da Silva Fabio Ribeiro Braga Luana Alcântara Borges Jair Mendes de Oliveira Walter dos Santos Lima Marcos Pezzi Guimarães Jackson Victor de Araújo 《Veterinary research communications》2014,38(2):101-106
Brazil has a herd of 212 million cattle and 171 million hectares of pastures that produce approximately 96 % of Brazilian beef. The Brazilian production system enables animal infection by endoparasites, which are considered one of the main obstacles for the development of this industry and are responsible for considerable economic losses. The control of parasitic diseases is performed via the administration of antiparasitic drugs, but they leave residues of the products in the treated animal, affect non-target organisms and select resistant strains of the parasites. The species D. flagrans and M. thaumasium are promising and sustainable alternatives for controlling gastrointestinal helminths of ruminants and other herbivores. In this study, we evaluated the efficacy of isolates of these species, formulated in a sodium alginate matrix and administered twice a week, to reduce the number of environmental infective larvae of gastrointestinal nematodes that affect prepubescent zebu females. The treated animals presented fewer eggs and a lower number of infective larvae per gram of faeces (p?<?0.05). The pastures occupied by treated animals showed a statistically significant reduction (p?<?0.05) of the number of L3 and, furthermore, the genera Cooperia sp., Haemonchus sp., and Oesophagostomum sp. were the most prevalent. The average weight of the animals did not differ statistically (p?>?0.05) among the treated and control groups. The use of sodium alginate pellets as vehicle for delivery of the fungus mycelia D. flagrans (isolate AC001) and M. thaumasium (isolate NF34A) proved effective in controlling trichostrongylids in prepubescent cows bred in the semi-arid region, with an effective reduction in the number of infective larvae in the pastures. 相似文献
32.
Dorgival Morais de Lima Jr. Francisco Fernando Ramos de Carvalho Maria Norma Ribeiro Ângela Maria Vieira Batista Bárbara Ferraz Ferreira Paulo de Barros Sáles Monteiro 《Tropical animal health and production》2014,46(6):995-1000
The use of native and adapted forages is an alternative for sustainable production systems in northeast Brazil. The goal of this study was to evaluate the substitution of Tifton 85 by maniçoba hay on the performance and carcass traits of Morada Nova hair sheep. The 16 lambs that were used in this study initially weighed 19.36?±?1.48 kg, were housed in individual pens, and were slaughtered at 58 days of confinement. The dry matter intake (839.84 g/day and 3.81 % WB) was higher (P?<?0.05) in sheep fed maniçoba hay. The feed conversion was 7.39 for sheep fed maniçoba hay. The empty body weight (21.61 kg) and cold carcass weight (11.40 kg) did not differ (P?>?0.05) between sheep fed different hay types. The replacement of Tifton 85 by maniçoba hay did not influence the loin eye area (cm2) or carcass compactness index (kg/cm). The replacement of Tifton 85 by maniçoba hay in Morada Nova sheep diet did not affect the weight gain or carcass characteristics. The maniçoba hay can be considered a forage resource for feeding sheep in Brazilian semiarid tropics. 相似文献
33.
Vanessa Diniz Vieira Thais Ferreira Feitosa Vinícius Longo Ribeiro Vilela Sérgio Santos Azevedo João Leite de Almeida Neto Dayana Firmino de Morais Ana Raquel Carneiro Ribeiro Ana Célia Rodrigues Athayde 《Tropical animal health and production》2014,46(2):355-361
Gastrointestinal helminthiasis represents an obstacle to goat raising, causing severe damage to herds such as growth retardation, weight loss, and even death. In this study, we aimed to determine the prevalence and risk factors associated to goat gastrointestinal helminthiasis in the Sertão region of Paraíba State, Brazil. A total of 256 goats from 54 farms were systematically sampled. Blood and fecal samples were collected from each animal for egg per gram (EPG), larval culture, and packed cell volume (PCV) analyses. We found that 79.3 % of the goats investigated were parasitized with gastrointestinal helminths. Significant correlation (p?=?0.004) was observed between the EPG and PCV of the animals studied, and it was observed that the EPG increases as the PCV decreases. In the larval culture, the most prevalent helminth was Haemonchus sp. (83.2 %). Age and sex were significant variables (p?≤?0.20) for the development of gastrointestinal helminths: 86.8 % of animals over 36 months of age and 81.7 % of females were infected. The variable type of animal exploitation was also significant, with 90.3 % (p?≤?0.20) of the animals presenting double suitability (milk and meat). The Sertão region of Paraíba State presents high prevalence of gastrointestinal helminthiasis in goats, and age and type of animal exploitation are the most relevant risk factors to the development of these parasites. 相似文献
34.
Jessica Maria Leite dos Santos Jomar Patrício Monteiro Wesley Lyeverton Correia Ribeiro Iara Tersia Freitas Macedo Ana Lourdes Fernandes Camurça-Vasconcelos Luiz da Silva Vieira Claudia Maria Leal Bevilaqua 《Veterinary parasitology》2014,199(3-4):160-164
Haemonchus contortus is the most prevalent nematode in Brazil. The objective of this study was to select 6 populations of H. contortus of known or suspected benzimidazole resistance status and characterize these using quantitative real-time polymerase chain reaction (qPCR) for single nucleotide polymorphisms (SNPs) F200Y, F167Y and E198A in the β-tubulin isotype 1 gene. qPCR was performed using DNA from a pool of 10 adult male H. contortus from a single animal per farm. Faecal egg count reduction test (FECRT) and egg hatch test (EHT) were used to determine the resistance status. Samples were obtained from 6 farms located in 5 counties in the Ceará State: Tauá, Boa Viagem, Quixadá, Santa Quitéria and Solonópole. The inbred-susceptible-Edinburgh (ISE) isolate was used as reference for comparative purposes in the qPCR. Benzimidazole resistance was detected by FECRT on all farms with efficacy values ranging from 0 to 51%. EC50 values as determined by EHT were all above 1.49 μg/ml. High frequencies of the resistant SNPs F200Y and F167Y alleles were detected but no resistance was detected at SNP E198A. Our results suggest that the SNPs F167Y and F200Y are both important for benzimidazole resistance in the studied populations. 相似文献
35.
G. V. Kozloski L. Oliveira C. H. E. C. Poli E. B. Azevedo D. B. David H. M. N. Ribeiro Filho S. G. Collet 《Journal of animal physiology and animal nutrition》2014,98(4):659-666
Data from twenty‐two digestibility trials were compiled to examine the relationship between faecal N concentration and organic matter (OM) digestibility (OMD), and between faecal N excretion and OM intake (OMI) by wethers fed tropical or temperate forages alone or with supplements. Data set was grouped by diet type as follows: only tropical grass (n = 204), only temperate grass (n = 160), tropical grass plus supplement (n = 216), temperate grass plus supplement (n = 48), tropical grass plus tropical legume (n = 60) and temperate grass with ruminal infusion of tannins (n = 16). Positive correlation between OMD and either total faecal N concentration (Nfc, % of OM) or metabolic faecal N concentration (Nmetfc, % of OM) was significant for most diet types. Exceptions were the diet that included a tropical legume, where both relationships were negative, and the diet that included tannin extract, where the correlation between OMD and Nfc was not significant. Pearson correlation and linear regressions between OM intake (OMI, g/day) and faecal N excretion (Nf, g/day) were significant for all diet types. When OMI was estimated from the OM faecal excretion and Nfc‐based OMD values, the linear comparison between observed and estimated OMI values showed intercept different from 0 and slope different from 1. When OMI was estimated using the Nf‐based linear regressions, the linear comparison between observed and estimated OMI values showed neither intercept different from 0 nor slope different from 1. Both linear comparisons showed similar R2 values (i.e. 0.78 vs. 0.79). In conclusion, linear equations are suitable for directly estimating OM intake by wethers, fed only forage or forage plus supplements, from the amount of N excreted in faeces. The use of this approach in experiments with grazing wethers has the advantage of accounting for individual variations in diet selection and digestion processes and precludes the use of techniques to estimate forage digestibility. 相似文献
36.
37.
Walmir Ribeiro de Carvalho Steel Silva Vasconcelos Osvaldo Ryohei Kato Carlos José Bispo Capela Débora Cristina Castellani 《Agroforestry Systems》2014,88(2):357-368
The current expansion of the oil palm (Elaeis guineensis Jacq.) in the Brazilian Amazon has mainly occurred within smallholder agricultural and degraded areas. Under the social and environmental scenarios associated with these areas, oil palm-based agroforestry systems represent a potentially sustainable method of expanding the crop. The capacity of such systems to store carbon (C) in the soil is an important ecosystem service that is currently not well understood. Here, we quantified the spatial variation of soil C stocks in young (2.5-year-old) oil palm-based agroforestry systems with contrasting species diversity (high vs. low); both systems were compared with a ~10-year-old forest regrowth site and a 9-year-old traditional agroforestry system. The oil palm-based agroforestry system consisted of series of double rows of oil palm and strips of various herbaceous, shrub, and tree species. The mean (±standard error) soil C stocks at 0–50 cm depth were significantly higher in the low (91.8 ± 3.1 Mg C ha?1) and high (87.6 ± 3.3 Mg C ha?1) species diversity oil palm-based agroforestry systems than in the forest regrowth (71.0 ± 2.4 Mg C ha?1) and traditional agroforestry (68.4 ± 4.9 Mg C ha?1) sites. In general, no clear spatial pattern of soil C stocks could be identified in the oil palm-based agroforestry systems. The significant difference in soil carbon between the oil palm area (under oil palm: 12.7 ± 2.3 Mg C ha?1 and between oil palm: 10.6 ± 0.5 Mg C ha?1) and the strip area (17.0 ± 1.4 Mg C ha?1) at 0–5 cm depth very likely reflects the high input of organic fertilizer in the strip area of the high species diversity oil palm-based agroforestry system treatment. Overall, our results indicate a high level of early net accumulation of soil C in the oil palm-based agroforestry systems (6.6–8.3 Mg C ha?1 year?1) that likely reflects the combination of fire-free land preparation, organic fertilization, and the input of plant residues from pruning and weeding. 相似文献
38.
The objective of this study was to investigate some aspects of horse resistance to natural infestations of Anocentor nitens and Amblyomma cajennense over a 2-year period. Free-living stages of A. nitens were used to evaluate the influence of season of the year on horse resistance. Every 2 weeks, 10 selected engorged females, weighing 150-329 mg, were removed from naturally infested horses and were individually placed into glass tubes closed with a cotton stopper, and maintained in an incubator. The biological parameters evaluated varied according to the season of the year, i.e., reproductive efficiency, maximum larval survival (MLS) and egg-hatching rates were significantly lower in spring/summer than in fall/winter. At 14-day intervals, females of A. nitens and A. cajennense were counted on each side of the body of five mares. A comparison between the animal with the lowest infestation and the animal with the highest infestation showed greater differences in animals infested with A. nitens than those infested with A. cajennense. Ten animals were found to carry 64.9% of the total parasite burden of A. cajennense and 88.6% of the highest infestations of A. nitens females. A seasonal variation on intensity of horse resistance to A. nitens was observed during the study. However, this was not observed for A. cajennense. Cross-resistance was observed in animals with the highest total number of A. cajennense and the highest number of A. cajennense adults (r=0.817), larvae (r=0.756), and A. nitens females (r=0.799). These results led to the conclusion that changes in horse resistance to A. nitens occur seasonally. As far as the total population of A. cajennense and the female stage of A. nitens are concerned, horses develop cross-resistance. 相似文献
39.
Ricardo Augusto Diniz Cabral Ferreira Magno Antonio Patto Ramalho Fernando Henrique Ribeiro Barrozo Toledo Angela de Fátima Barbosa Abreu 《Plant Breeding》2015,134(5):599-604
In the common bean crop in Brazil, the requirement of the value for cultivation and use trials is that these experiments must be conducted over two years in three locations per region. Information in regard to the necessary number of years to ensure precision in cultivar recommendation and the influence of evaluated years in the estimation of the GE interaction are still scarce. Using grain yield of five check varieties assessed over 11 years in three sowing seasons per year, the aims of this study are as follows: to measure the relative contribution of the GE interaction, evaluating the implication of the number of years in the estimates of the GE interaction, and infer how many years are needed to ensure precision in cultivar recommendation. For instances, analysis of variance was carried out involving all environments and also combinations of years. The results showed that the GE interaction was greater than all other cross‐effects involving lines. The use of at least two years allows good coincidence in cultivar recommendation compared to the whole period. Increasing the evaluation time is a good strategy, especially when it is difficult to grow three different sowing seasons. 相似文献
40.
Valentão P Andrade PB Rangel J Ribeiro B Silva BM Baptista P Seabra RM 《Journal of agricultural and food chemistry》2005,53(12):4925-4931
To check the influence of the conservation procedure in the chemical composition of chanterelle mushroom, phenolic compounds and organic acids of samples preserved under four different conditions (drying, freezing, conservation in olive oil and in vinegar) were determined. Phenolics and organic acids were analyzed by HPLC-DAD and HPLC-UV, respectively. The results showed that chanterelle is characterized by the presence of six phenolic compounds (3-, 4-, and 5-O-caffeoylquinic acid, caffeic acid, p-coumaric acid, and rutin) and five organic acids (citric, ascorbic, malic, shikimic, and fumaric acids). Samples preserved in olive oil also exhibited hydroxytyrosol, tyrosol, luteolin, and apigenin, whereas conservation in vinegar led to the detection of hydroxytyrosol, tyrosol, and tartaric acid in the analyzed samples. The conservation procedures to which chanterelle samples were subjected seem to affect the qualitative and quantitative phenolics and organic acids profiles. 相似文献