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991.
992.
1. The aim of this work was to evaluate the shelf life of turkey meat from different colour categories (Pale, Soft and Exudative (PSE)-like), intermediate and dark), packaged under aerobic or modified atmosphere (MAP) conditions; also to establish a relationship between microbial quality and total volatile basic nitrogen (TVB-N), evaluating its capacity for shelf life determination. 2. Breasts were selected according to luminance (L*) and pH(24): L >/= 51 and pH < 5.8 for light colour, 43 < L < 51 for intermediate colour, L 5.8 for dark colour. Sliced meat was packaged under aerobic or MAP conditions with 50% N(2) and 50% CO(2), then stored in the dark at 0 +/- 1 degrees C for periods of 12 or 25 d. Meat under aerobic conditions was evaluated for microbiological characteristics and TVB-N on d 0, 5 and 12. This evaluation was extended to include d 19 and 25 when samples were under MAP conditions. 3. The dark meat group after 12 d of storage in aerobiosis presented significantly higher plate counts of aerobic mesophilic, psychrotrophic micro-organisms and higher TVB-N than other meat colour categories. The shelf life of turkey meat under MAP was one week longer for intermediate and light colour meat (20 d) than for dark meat. TVB-N values of 20 to 30 mg NH(3)/100 g turkey meat correspond to advanced spoilage stages. We proposed 14 mg NH(3)/100 g as the limit of freshness acceptability for turkey meat. 4. TVB-N was an indicator of turkey meat microbial spoilage but was not a suitable early predictor for microbial spoilage and in particular for turkey meat stored under MAP conditions because counts of micro-organisms were moderately correlated (Pseudomonas spp. and Enterobacteriaceae) with this index, as they were inhibited by MAP gas mixture and storage temperature used in the present study.  相似文献   
993.
Objectives : To determine the reliability of early passive hip laxity examination in predicting moderate and severe hip dysplasia. Methods : The passive hip laxity of 104 Estrela Mountain dogs was evaluated using the Ortolani method, conventional hip‐extended radiography and the PennHIP method, when the animals were between four and 12 months of age. After the age of one, dogs were re‐examined for hip dysplasia using the Fédération Cynologique Internationale scoring system. The passive hip laxity results were subsequently compared with the Fédération Cynologique Internationale scores for sensitivity, specificity, positive predictive value, negative predictive value and accuracy. Results : The PennHIP method achieved the best results in specificity (93 per cent), positive predictive value (91 per cent) and accuracy (88 per cent), and the Ortolani method was the best in sensitivity (92 per cent) and negative predictive value (92 per cent). Clinical Significance : The Fédération Cynologique Internationale grades D and E can be predicted with confidence even before animals are one year old.  相似文献   
994.
Calicivirus infection of adult rabbits induces the so-called rabbit haemorrhagic disease (RHD) that kills 90% or more of the infected animals; in contrast, young rabbits (up to 8-week-old animals) are resistant to the same infectious agent. We report that calicivirus inoculation of young rabbits induced moderate titres of antiviral antibodies. When these rabbits reached adulthood, a second calicivirus inoculation resulted in resistance to RHD and boosting of antibody titres in half of the rabbits. Adoptive transfer of sera from calicivirus-infected young rabbits to na?ve adult rabbits conferred resistance to RHD. We conclude that calicivirus infection of young rabbits induces specific anti-calicivirus antibodies that will protect them from RHD when they reach adulthood.  相似文献   
995.
Larvae of Oestrus ovis (Diptera: Oestridae) are ubiquitous parasites of nasal and sinusal cavities of sheep and goats. According to the chronobiology of O. ovis infections in Sardinia and the seasonal pattern of the IgG response, the optimal period to investigate the relationships between O. ovis larval populations and intensity of local and systemic IgG antibody responses was mid-July in the summer season. Sarda x Lacaune ewes (n=186), divided into three ram-families were used in the study. Systemic and local IgG responses were measured by ELISA tests using second stage larval crude extracts (L2CE) and L2 (L2SGC) and L3 (L3SGC) salivary gland contents as coating antigens. The number of larval instars, larval length of L1, L2 and L3 larvae, and larval weight of L2 and L3 larvae were individually recorded after ewe necropsy. Negative correlations among larval establishment and/or larval development on the one hand and intensity of local or systemic IgG responses on the other hand were found in two out of three studied ram-families.  相似文献   
996.
Thermal analysis could rapidly and easily predict nutritional value of ruminant feeds. The hypothesis is that crambe meal (CM) has a quality similar to that of soybean meal (SM), and the objective of this study was to determine the nutritional characteristics of CM and compare them to those of SM. CM had greater concentrations of phytic acid (26.3 vs. 16.0 g/kg) and phenol compounds (615 vs. 393 mg gallic acid (GAE)/kg) than SM. In vitro dry matter (DM) digestibility was lower for CM than SM (752 vs. 975 g/kg DM). Cumulative in vitro gas production at 48 h of incubation (14.1 vs. 19.4 mL/100 mg substrate DM), and energy release (4.5 vs. 5.7 kJ/g substrate DM) were lower for CM than SM. CM had a higher concentration of low digestible fiber, hence degradability of DM was lower and the proportion of indigestible fraction was greater for CM than SM. High concentrations of indigestible compounds were likely responsible for lower gas production of CM compared to SM. These results suggest CM quality is lower than that of SM and that thermal analysis is a useful tool to precisely determine the nutritive value of oilseed residues.  相似文献   
997.
Tropical Animal Health and Production - Semen contaminated with microorganisms can disseminate serious diseases including brucellosis. The objectives of this study were to detect Brucella-specific...  相似文献   
998.
Natriuretic peptides (NPs) are known to regulate reproductive events in polyovulatory species, but their function and regulation in monovulatory species remain to be fully characterized. Using a well‐established in vivo model, we found that bovine granulosa cells from follicles near the deviation stage express mRNA for the three NP receptors (NPR1, NPR2 and NPR3), but not for NP precursors (NPPA, NPPB and NPPC). The abundance of NPR3 mRNA was higher in dominant compared to subordinate follicles at the expected time of follicular deviation. After deviation, mRNA for all NP receptors was significantly more abundant in the dominant follicle. Intrafollicular inhibition of oestrogen receptors downregulated NPR1 mRNA in dominant follicles. In granulosa cells from preovulatory follicles, NPPC mRNA increased at 3 and 6 h after systemic GnRH treatment, but decreased at 12 and 24 h to similar levels observed in samples collected at 0 h. After GnRH treatment, NPR1 mRNA was upregulated at 24 h, NPR3 mRNA gradually decreased after 3 h, while NPR2 mRNA was not regulated. The mRNA expression of the enzyme FURIN increased at 24 h after GnRH treatment. These findings revealed that the expression of mRNA encoding important components of the NP system is regulated in bovine granulosa cells during follicular deviation and in response to GnRH treatment, which suggests a role of NP system in the modulation of these processes in monovulatory species.  相似文献   
999.
Two experiments were carried out to determine the levels of supplementation of inorganic selenium (Se) and vitamin E (VE ) in diets of quails aged 0–14 and 14–35 days old. A completely randomized design was used in a factorial design (Se = 0.1125; 0.2250; 0.3375 and 0.4500 mg kg?1 diet?1 × VE  = 10; 23; 36 and 49 IU  kg?1 diet?1). In experiment 1, quail (n  = 2,400) were aged 0–14 days and were divided into 16 treatments, with three replicates of 50 birds. In experiment 2, quail (n  = 1,680) were aged 14–35 days and were divided into the same treatments, with three replicates of 35 birds. At age 0–14 days, the levels of VE did not affect performance (p  > .05); however, the feed conversion (FC ) was influenced by a quadratic effect (p  = .0515), according to the level of Se, with a higher level estimated at 0.29 mg Se kg?1 diet?1. At age 14–35 days, there was a linear effect with interaction (Se × VE ), for FC (p  = .0150) and weight gain (WG ; p  = .0266). FC (Se, p  = .0048 and VE , p  = .0019) and WG (Se, p  = .0049 and VE , p  = .0068) improved linearly with increasing levels of Se and VE . The feed intake (FI ) decreased linearly (p  = .0582) as a function of VE . The carcass yield showed a quadratic effect (p  = .0056) on the levels of VE , with a higher yield estimation of 27.24 IU VE /kg of diet. It can be concluded that the optimum level of supplementation at age 0–14 days was 0.29 mg Se kg?1 diet?1 and 10 IU VE  kg?1 diet?1 and at age 14–35 days, it was 0.4500 mg Se kg?1 diet?1 and 49 IU of VE  kg?1 diet?1.  相似文献   
1000.
Fungi of the Cryphonectriaceae family are globally known to be tree pathogens. In Brazil, several species of Chrysoporthe have been found causing stem and branch cankers in Pleroma (= Tibouchina) spp. Recently, Chrysoporthe puriensis was described as a new species causing stem and branch cankers in Pleroma granulosum, Pleroma candolleanum, and Pleroma heteromallum, all native species of the Melastomataceae family. During an investigation to collect isolates of the Cryphonectriaceae family in an important Brazilian biome, the Atlantic Forest, in Serra do Mar, structures typical of Chrysoporthe species were found in a different host, Pleroma mutabile. Fruiting bodies present in the bark of these trees were collected and isolated. The isolates were submitted on morphological characterization and phylogenetic analyses of the internal transcribed spacer (ITS) and β-tubulin gene regions using Maximum likelihood, Bayesian inference and Maximum parsimony methods. The isolates collected, for this study, were identified as C. puriensis. Pathogenicity tests on seedlings of Pleroma species and Eucalyptus clones revealed C. puriensis can infect and cause canker in these plant species as mortality. The results demonstrate the importance of delimiting the C. puriensis collection range to track its dissemination in other hosts. No host specificity was observed in the inoculation tests, suggesting this is an important finding, the pathogen causes diseases and mortality in several plants of the Atlantic Forest. Additionally, the pathogen can affect others hosts, such as Eucalyptus clones in commercial plantations.  相似文献   
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