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91.
Background: Play behavior has been proposed as a new potential indicator of animal welfare. Animals play only if they are in a relaxed state. Play may improve adaptability to challenging environments which may be of interest in the breeding objective. Little information is available on play behavior in livestock species. The aim of the present study is to investigate whether play behavior in post-weaned piglets can be induced instantly in the presence of additional space and whether play markers are body weight, sex, and litter dependent, it is investigated whether playfulness is elicited by the moment or if this measure is consistent over different days. Methods: Thirty two piglets from four litters were released into a corridor and video recorded for eight min at 37, 41, 44 and 48 d of age. The first test was considered as an adjustment period and was not included in the analysis. In the second to the fourth test, joyful brusque movements (jumping, turning and running) were recorded with a camera and total number of movements (JOY#) and total time (JOYtime) were estimated individually. Animals were weighed at 41 d of age. Results: Females had higher scores of JOY# and JOYtime than males but this was significant only for JOY# at 41 d of age (P 〈 0.05). The effect of age was highly significant both for JOY# and JOYtime (P 〈 0.01). Animals with a higher JOY# and JOYtime also expressed a higher JOY# and JOYtime in the other tests, but this was significant only between 44 and 48 d of age (P〈 0.01). Body weight at 41 d of age was not significantly related to JOY# and JQYtime in any of the tests. Conclusions: Locomotor play was induced instantly by the provision of increased space allowance. Litter origin had a significant effect on play behavior. In addition, locomotor play scores were consistent between two of the three tests.  相似文献   
92.
Faecal samples from 224 roe deer (Capreolus capreolus) and 381 wild boars (Sus scrofa) shot during the 2008-2009 hunting season (August-January) in Galicia (NW Spain) were examined to determine the presence and intensity of infection by Cryptosporidium and Giardia. Analysis of a single sample from each of the roe deer revealed that the prevalence of cryptosporidiosis and giardiosis was 1.3% and 5.3% respectively. The prevalence of Giardia infection was significantly higher in juvenile female roe deer than in adult females, but no other significant differences were found in relation to age and sex. In wild boars, the prevalence of cryptosporidiosis and giardiosis was 7.6% and 1.3% respectively. The prevalence of Cryptosporidium infection was significantly higher in juvenile male wild boars than in adult males, but no other significant differences were found in relation to age or sex. In both groups of wild animals, the number of Cryptosporidium oocysts per gram of faeces (OPG) ranged from 5 to 200 and the number of Giardia cysts per gram of faeces (CPG) was between 5 and 47; there were no significant differences between the two groups with respect to number of infections. This is the first large study of Cryptosporidium and Giardia in roe deer and wild boars in hunting areas in Spain and the results demonstrate a low, but widespread prevalence of Cryptosporidium and Giardia in these animals.  相似文献   
93.
In this study, the protection afforded by a Neospora caninum inactivated vaccine formulated with three different adjuvants (water-in-oil emulsion, aluminum hydroxide with CpG oligodeoxynucleotides and aluminum hydroxide with ginseng extract) and three different parasite doses (10(5), 5 × 10(5) or 10(6) inactivated whole tachyzoites) was evaluated using a mouse model. Mice were immunized subcutaneously twice at three-week intervals with inactivated Nc-Spain 1H tachyzoites and challenged by intraperitoneal inoculation with 10(6) live Nc-1 tachyzoites. The efficacy of the immunization was evaluated in non-pregnant BALB/c mice on days 1 and 5 (acute infection phase) and days 14 and 30 (chronic infection phase) post-challenge. The results showed the ability of water-in-oil emulsion combined with inactivated 5 × 10(5) tachyzoites to induce protection against neosporosis during the chronic stage, limiting parasite multiplication in the brain. Aluminum hydroxide-ginseng extract and inactivated tachyzoites reduced the number of parasites circulating in the blood during acute phase but failed to limit the establishment of chronic infection. On the other hand, a dose-effect was observed in groups vaccinated with aluminum hydroxide-ginseng extract in which the lesion severity increased as the inactivated tachyzoite dose. This study demonstrates that efficacy can significantly vary depending on the adjuvant, the dose of antigen and the phase of N. caninum infection in which the vaccine is tested.  相似文献   
94.
This study was conducted to determine: (1) the associations between anti-Fasciola hepatica antibody levels in milk and some productive and reproductive parameters in dairy cattle, and (2) the threshold antibody level associated with loss of productivity, at both herd and individual level. Anti-F. hepatica antibodies were analysed by MM3-SERO ELISA in milk samples from the bulk tanks of 490 dairy farms and from 686 lactating cows. The results of general linear model analysis revealed a significant (P<0.05) negative association between the F. hepatica infection status at herd level, determined by analysis of specific antibodies in bulk tank milk, and the average herd milk production. Highly positive herds (MM3-SERO ELISA result>0.405) produced an average of 1.5 kg milk/cow per day less than the negative herds. At cow-level, the mixed model analysis also revealed a significant (P<0.05) association between anti-F. hepatica antibody levels and milk yield. A significant (P<0.05) average reduction of 2 kg milk/day was observed in cows with highly positive ELISA results (>0.762) in relation to cows with negative results. The results of the study led us to conclude that MM3-SERO ELISA is a powerful tool that can be successfully applied, if appropriate "economic thresholds" are established, to identify herds and cows suffering from milk production losses associated with natural infection by F. hepatica.  相似文献   
95.
96.
Distended lacteals, described as expanded white villi in duodenum, are strongly indicative of primary intestinal lymphangiectasia. In the present study, we evaluated the significance of white spots present in the duodenal mucosa of dogs with lymphocytic plasmacytic enteritis (LPE). Fifty dogs with LPE were included in this study, and white spots were detected in the duodenal mucosa in 22 dogs during endoscopy. Hypoproteinemia was more frequent in dogs with white spots than in dogs without spots (p = 0.02). Serum protein and albumin concentration were significantly lower in LPE dogs with white spots (p = 0.038) compared to LPE dogs without white spots (p = 0.039). There was a significant correlation between white spots density and lymphatic dilatation histological scores (p = 0.023; ρ = 0.481). These results suggest that the presence of white spots in the duodenal mucosa of dogs is not a finding exclusive for intestinal lymphangiectasia. Low serum protein and albumin concentrations together with lymphatic dilatation seem to be related to the presence of white spots in the duodenal mucosa of LPE dogs.  相似文献   
97.
Taste and aroma related compounds have been analyzed in a collection of four traditional varieties and two tomato hybrids, representing a wide variability in fruit shape and color, grown in different environments: screenhouse and open field. Protected cultivation tended to show lower sugar concentration (fructose and glucose) but similar acid contents (citric, malic, and glutamic acids). The decreased levels of sucrose equivalents and the similar ratios of sucrose equivalents to citric or glutamic acid contents indicated that protected cultivation, despite being useful to reduce the incidence of pests and viral diseases, reduces the organoleptic quality. Additionally, it doubles the interaccession variability and increased the level of intra-accession variability. In the case of aroma, the genotypic effect was considerably higher than the environmental component on the 12 main volatiles analyzed. Only hexanal and methyl salicylate were significantly affected by environment, while 10 out of 12 volatiles were affected by the genotype. Biplot analysis showed that, even in considerably different environments, it is possible to identify genotype-dependent main aroma profiles. In the case of 13 background volatiles, the environment showed no significant effects and the genotypic effect was lower, though it is possible to identify genotypic trends in background notes.  相似文献   
98.
The agronomic environments in which tomatoes are cultivated potentially affect the levels of antioxidants and other metabolites in commercial products. In this study, biochemical and metabolomic techniques were used to assess the differences between ketchups produced by organic and conventional systems. An untargeted metabolomic approach using QToF-MS was used to identify those nutrients that have the greatest impact on the overall metabolomic profile of organic ketchups as compared to conventional ones. Individual polyphenols were quantified using LC-ESI-QqQ. This multifaceted approach revealed that the agronomic environment in which tomatoes are grown induces alterations in the content of antioxidant capacity, phenolics, and other metabolites in ketchups. Organic cultivation was found to provide tomatoes and tomato-derived products with a significantly higher content of antioxidant microconstituents, whereas glutamylphenylalanine and N-malonyltryptophan were detected only in conventional ketchups.  相似文献   
99.
This paper reports arsenic speciation in edible seaweed (from the Galician coast, northwestern Spain) produced for human consumption. Chondrus crispus , Porphyra purpurea , Ulva rigida , Laminaria ochroleuca , Laminaria saccharina , and Undaria pinnatifida were analyzed. The study focused on arsenosugars, the most frequently occurring arsenic species in algae. As(III) and As(V) were also determined in aqueous extracts. Total arsenic in the samples was determined by microwave digestion and inductively coupled plasma mass spectrometry (ICPMS). For arsenic speciation, a water extraction especially suitable for arsenosugars was used, and the arsenic species were analyzed by liquid chromatography with both anionic and cationic exchange and ICPMS detection (LC-ICPMS). The total arsenic content of the alga samples ranged from 5.8 to 56.8 mg As kg(-1). The mass budgets obtained in the extracts (column recovery × extraction efficiency) ranged from 38 to 92% except for U. pinnatifida (4%). The following compounds were detected in the extracts: arsenite (As(III)), arsenate (As(V)), methylarsonate (MA), dimethylarsinate (DMA), sulfonate sugar (SO(3)-sug), phosphate sugar (PO(4)-sug), arsenobetaine (AB), and glycerol sugar (Gly-sug). The highest concentrations corresponded to the arsenosugars.  相似文献   
100.
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