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151.
An ELISA test was used to determine the persistence of antibody levels in horses following treatment for Trypanosoma evansi. In 17 horses with T. evansi from two farms treated and cured with quinapyramine sulphate, ELISA antibody levels fell progressively post-treatment, but remained with positive results for 22.6 months in one horse, 12.8 months in a second, 4.1 months in another four and 2.3 months in three, whilst the rest became negative at 2.3 months. In two horses that suffered a post-treatment infection relapse the decrease in ELISA levels was only temporary, and a new increase in antibody levels was proven. The follow-up of these antibody levels could prove useful in clinical cases and in epidemiological studies, as well as for assessing the efficacy of drug treatment. 相似文献
152.
153.
Acetylene reduction activity by root nodules of the legumeErythrina poeppigiana, growing as shade tree in a Costa Rican coffee plantation, was estimated. The mean activity found was 15.7 nmole C2H4 · mg (dry weight)–1 · h–1. Root nodules collected at different distances from theErythrina stem showed the same activity per dry weight unit. However, as the biomass of the nodules was highest near the stem, was the acetylene reduction activity (expressed per soil volume) maximal near theErythrina stem and declined with distance. 相似文献
154.
Borzacchiello G Russo V Russo M 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(5):247-249
Ovarian tumours among domestic animals are frequently encountered in bitch. Cyclooxygenase-2 (COX-2) expression has been evaluated in different kind of canine primary epithelial neoplasms. Eleven canine ovarian carcinomas and two normal samples were evaluated immunohistochemically for COX-2 expression. Nine of 11 carcinoma samples (81%) expressed COX-2 enzyme isoform. The immunoreactivity was intracytoplasmically recorded and the intensity ranged from faint to strong. Our results show that COX-2 is expressed in canine ovarian carcinoma, suggesting a potential role of COX-2 in canine ovarian carcinogenesis. 相似文献
155.
L. Fontanesi G. Schiavo E. Scotti G. Galimberti D.G. Cal A.B. Samor M. Gallo V. Russo L. Buttazzoni 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(3):239-246
In this study, we investigated whether a selection programme based on boar genetic evaluation obtained with a classical BLUP animal model can change allele frequencies in a pig population. All Italian Large White boars born from 1992 to 2012 with estimated breeding value reliability >0.85 (n = 200) were selected among all boars of this breed. Boars were genotyped with markers in major genes (IGF2 intron3‐g.3072G>A, MC4R p.D298N, VRTN PRE1 insertion, PRKAG3 p.I199V and FTO g.276T>G). Genotyping data were analysed grouping boars in eight classes according to their year of birth. To evaluate the influence of time on allele frequencies of the genotyped markers, multinomial logistic regression models were computed. Four of five polymorphic sites (IGF2, MC4R, VRTN and FTO) showed significant (p < 0.01) changes in allele frequencies over time due to a progressive and continuous increase of one allele (associated with higher lean meat content, higher average daily gain and favourable feed: gain ratio) and, consequently, decrease of the other one, following the directional selection of the selection programme of this pig breed. The retrospective analysis that was carried out in Italian Large White boars suggests that selection based on methodologies assuming the infinitesimal model is able to modify in a quite short period of time allele frequencies in major genes, increasing the frequency of alleles explaining a relevant (non‐infinitesimal) fraction of the overall genetic variability for production traits. 相似文献
156.
Q fever is a zoonosis caused by the obligate intracellular bacterium, Coxiella burnetii. Aborting domestic ruminants are the main source of human infection. In January 2003, an abortion episode occurred in a dairy caprine herd where 18/60 (30%) goats experienced reproductive problems: 4/60 (7%) aborted and 14/60 (23%) had stillbirths. Serological screening for abortion-related infectious diseases suggested Q fever. The diagnosis of C. burnetii infection was confirmed with PCR based on the occurrence of C. burnetii shedding into vaginal mucus, faeces and colostrums taken after kidding from the affected animals. The pregnancy following this episode resulted in one abortion and four stillbirths; three of those goats had already experienced reproductive failure during the previous kidding season. The seroprevalence of C. burnetii infection and the bacteria shedding were investigated using both ELISA and PCR assays, respectively, during the course of the initial and subsequent kidding seasons. Serological testing, performed on the whole herd 6 weeks after the abortion episode, showed 48/60 (80%) of ELISA positive goats. PCR assay performed on both vaginal swab and milk samples showed that the bacterium was shed for almost four months after the outbreak. C. burnetii DNA was also amplified from vaginal swab and milk samples taken from goats after the second kidding season. Furthermore, the bacteria were found into 14 vaginal swabs and 12 milk samples taken from infected females at both kidding seasons. 相似文献
157.
158.
Corrado Costa Stefano D’Andrea Riccardo Russo Francesca Antonucci Federico Pallottino Paolo Menesatti 《Aquaculture International》2011,19(4):765-778
European sea bass, Dicentrarchus labrax, is one of the main species cultured in Europe. In this study, non-invasive techniques such as visible-near infrared spectroscopy
and dynamometric analysis were used to discriminate concrete tank–cultured sea bass from sea cage–cultured sea bass. A total
of 198 samples were collected at six time points from 3 Italian fish farms. A partial least squares analysis was conducted
on individual animals at 48 and 96 h post-mortem to determine whether textural and spectral parameters can discriminate between concrete tank– and sea cage–reared sea bass.
The results of this analysis demonstrated that spectral measurements better discriminate individual animals at 48 h post-mortem (87% in the independent test) with respect to 96 h post-mortem (66.7% in the independent test). Differences in texture were observed between the two groups of fish, but the texture changed
in the time. The texture in sea cage–cultured fish showed higher values of measured force (N) with respect to fish reared
in concrete tanks at 48 h post-mortem. Instead, opposite results were observed at 96 h post-mortem. Fillet colour were influenced by both farm and rearing condition. 相似文献
159.
V Russo L. Buttazzoni C. Baiocco M. R. Davoli N. L. Nanni Costa O. C. Schivazappa P. C. Virgili 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2000,117(1):37-42
Previous studies suggested that proteolysis lasting for many months after slaughtering could be responsible for excessive softness in dry-cured hams. Also, the long-term activity of muscle proteinases is mainly attributed to cathepsin B. Should an additive genetic component exist for the activity level of cathepsin B, such information could be used as a selection criterion for improving meat quality for dry-cured ham production. Data on the growth rate, carcass composition, and meat quality of 234 Large White pigs raised in a test station under a &lsquo| quasi ad libitum ' nutritive level and slaughtered at around 160 kg live weight were analysed using a blup - mt -animal model. The cathepsin B activity level showed a moderate heritability (0.23–0.28) in all analyses, and negative genetic correlations with daily gain (− 0.34 to − 0.52) and backfat thickness (− 0.40 to − 0.86), but, with large standard errors. These results suggest that a genetic component exists in explaining the variability of the cathepsin B activity level. Further studies are necessary to confirm the outcome and to investigate genetic correlations with other traits currently under selection. 相似文献
160.
The antioxidant ability of the flavanol catechin and its planar derivative, catechin 1 (PC1), was explored using the DF/B3LYP theoretical approach. Their potentiality in the hydrogen abstraction and electron transfer reactions, the main working mechanisms of antioxidants, was evaluated by computing the values of two key parameters, which are the OH bond dissociation energy and the ionization potential. Results indicated that the effect of a planar arrangement in the catechin molecule is small in the case of the hydrogen abstraction but greater for the electron transfer, since the in vacuo ionization potential value decreases by about 3 kcal/mol. The reaction of these molecules with the hydroperoxyl radical (*)OOH indicated that the H(*) abstraction is faster with the planar catechin. 相似文献