999 resultados para commercial eggs
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This study aimed at determining the minimum time required for the penetration of Salmonella Heidelberg inside the eggs after contact with contaminated material. Recently-collected brown and white eggs from laying hens between 45-50 weeks of age, reared in a commercial poultry house, were artificially contaminated by contact with wood shavings moistened with liquid inoculum of Salmonella Heidelberg in stationary-growth phase (10³-10(4) CFU g-1). According to type (white or brown), eggs were distributed into three different groups, with four replicates each: negative control group (no artificial contamination), positive control group (analyzed externally immediately after contamination and internally after the maximum storage period of the test group) and test group. Eggs were stored at controlled environmental temperature varying from 25ºC to 30ºC. In the test group, eggs contents (yolk and albumen) were pooled and analyzed after 1:00, 1:30, 2:00, 2:30, 3:00, 3:30, and 4:00 hours after contamination for the presence of Salmonella Heidelberg in 25g of this pool. The experimental unit consisted of five eggs in each test. The analysis protocol included pre-enrichment, selective enrichment, plating on selective agar, and biochemical and serological tests. The results obtained were submitted to logistic regression, which indicated that the presence of Salmonella Heidelberg was verified after 2:16 h and 2:44 h of contact with white and brown eggs, respectively.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Ciência e Tecnologia Animal - FEIS
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This paper aimed at evaluating the influence of diets containing different isotopic values of carbon-13 turnover on the half-life of egg (yolk + albumen), yolk and albumen individually, and blood of poultry using δ‰ 13C isotopic variation. Commercial layers fed four experimental isocaloric and isonitrogenous diets (RC 4, RC 3, RMC 4 and RMC 3) containing different isotopic values, during an experimental period of 56 days. Turnover of the studied tissues was influenced by the experimental diets. Blood and albumen were more influenced by dietary treatments as compared to egg and yolk. The RMC 3 diet induced better performance (better feed intake and higher egg production) due faster rate of carbon substitution than the RC 4 diet, and lower half-life for egg (yolk + albumen), yolk, and albumen.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Queensland fruit fly, Bactrocera tryoni (Froggatt), is a polyphagous pest, and many citrus types are included among its hosts. While quantification of citrus host use by B. tryoni is lacking, citrus is generally considered a ‘low pressure’ crop. This paper investigates B. tryoni female oviposition preference and offspring performance in five citrus types; Murcott mandarin (Citrus reticulata), Navel orange and Valencia orange (Citrus sinensis), Eureka lemon (Citrus limon) and yellow grapefruit (Citrus paradisi). Oviposition preference was investigated in laboratory-based choice and no-choice experiments, while immature survival and offspring performance were investigated by infesting fruits in the laboratory and evaluating pupal recovery, pupal emergence and F1 fecundity. Fruit size, Brix level and peel toughness were also measured for correlation with host use. Bactrocera tryoni demonstrated an oviposition preference hierarchy among the citrus fruits tested; Murcott and grapefruit were most preferred for oviposition and lemon the least, while preference for Navel and Valencia was intermediate. Peel toughness was negatively correlated with B. tryoni oviposition preference, while no significant correlations were detected between oviposition and Brix level or fruit size. Immature survival in the tested fruit was very low. Murcott was the best host (21% pupal recovery), while all other citrus types that showed pupal recovery of 6% or lower and no pupae were recovered from Valencia orange. In pupae recovered from Navel orange and lemon, adult eclosion was greatly reduced, while in grapefruit and lemon, no eggs were recovered from F1 adults. Based on these laboratory results, many commercial citrus varieties appear to be poor hosts for B. tryoni and may pose a low post-harvest and quarantine risk. These findings need to be confirmed in the field, as they impact on both pre-harvest and post-harvest countermeasures.
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Herpesviral haematopoietic necrosis is a disease of goldfish, Carassius auratus, caused by Cyprinid herpesvirus-2 (CyHV-2) infection. Quantitative PCR was carried out on tissue homogenates from healthy goldfish fingerlings, broodfish, eggs and fry directly sampled from commercial farms, from moribund fish submitted to our laboratory for disease diagnosis, and on naturally-infected CyHV-2 carriers subjected to experimental stress treatments. Healthy fish from 14 of 18 farms were positive with copy numbers ranging from tens to 10(7) copies mu g(-1) DNA extracted from infected fish. Of 118 pools of broodfish tested, 42 were positive. The CyHV-2 was detected in one lot of fry produced from disinfected eggs. Testing of moribund goldfish, in which we could not detect any other pathogens, produced 12 of 30 cases with 10(6)-10(8) copies of CyHV-2 mu g(-1) DNA extracted. Subjecting healthy CyHV-2 carriers to cold shock (22-10 degrees C) but not heat, ammonia or high pH, increased viral copy numbers from mean copy number (+/- SE) of 7.3 +/- 11 to 394 +/- 55 mu g(-1) DNA extracted after 24 h. CyHV-2 is widespread on commercial goldfish farms and outbreaks apparently occur when healthy carriers are subjected to a sharp temperature drop followed by holding at the permissive temperature for the disease.
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Catches of important commercial fish such as red sea bream, flat fish, and yellowtail are decreasing in Japan. In order to sustain these species it is especially important that their distribution and biomass at all life stages are known. However, information on the early life stages of these species is limited because identifying the eggs and larvae of such fish is sometimes extremely difficult.
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Air-dried and 3 mm pore size sieved soil was amended with neem crude formulations (leaves and cake) @ 3% w/w and a refined product, aza @ 0.05 and 0.1 w/w. Three days after treatment, 500 eggs of M. javanica held in 2 ml water were added in each dish. In another experiment, soil was amended with neem crude formulations @ 10. 5, 2.5 and 1% w/w and refined formulation aza @ 0.025, 0.05, 0.1 and 0.5% w/w. Three days after amendment 1000 plus minus 21 freshly hatched J2 held in 3 ml water were added to the amended soil. Untreated soil was kept as control. Comparison of treatments means showed that all the neem formulations caused significant reduction of hatching. Neem crude formulations were more effective in reducing hatching as compared to commercial product aza. Among the crude formulations, neem leaves were most effective in reducing hatching. In other experiment all the doses of neem crude and refined formulations differed significantly with control in reducing the mobility of juveniles. It was observed that by increasing the dose of the formulations the mobility was reduced accordingly.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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This study was designed to evaluate the effects of different fat sources on the performance, egg quality, and lipid profile of the egg yolks of layers in their second production cycle. The fat sources were cottonseed oil, soybean oil, lard, sunflower oil, or canola oil. Experimental diets were fed to postmolt ISA Brown layers at 70 wk of age and the experimental period was 74 to 86 wk of age. The different fat sources did not influence performance or eggshell quality, but lipid profile of the egg yolk changed as a function of dietary fat sources. In general, the best changes, such as lower level of saturated fatty acids, higher levels of alpha-linolenic acid and DHA, and lower linoleic acid levels, were promoted by the addition of canola oil, but it did not promote enrichment of the eggs with polyunsaturated fatty acids.