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1.
Hydrogen peroxide (H2O2) localization and roles of peroxidases, malondialdehyde and reduced glutathione were compared in leaves of apricot (Prunus armeniaca) plants asymptomatic, European Stone Fruits Yellows (ESFY)-symptomatic and recovered. Nested PCR analysis revealed that Candidatus Phytoplasma prunorum, is present in asymptomatic, symptomatic and recovered apricot trees, confirming previous observations on this species, in which recovery does not seem to be related to the disappearance of phytoplasma from the plant.H2O2was detected cytochemically by its reaction with cerium chloride, which produces electron-dense deposits of cerium perhydroxides. H2O2was present in the plasmalemma of the phloem cells of recovered apricot plant leaves, but not in the asymptomatic or symptomatic material. Furthermore, by labelling apricot leaf tissues with diaminobenzidine DAB, no differences were found in the localization of peroxidases.Protein content in asymptomatic, symptomatic and recovered leaves was not significantly different from one another. In contrast, guaiacol peroxidase activity had the following trend: symptomatic > recovered > asymptomatic, whereas reduced glutathione content followed the opposite trend: asymptomatic > recovered > symptomatic. Moreover, no differences were observed in malondialdehyde concentrations between asymptomatic, symptomatic and recovered leaves. The overall results suggest that H2O2 and related metabolites and enzymes appear to be involved in lessening both pathogen virulence and disease symptom expression in ESFY-infected apricot plants.  相似文献   
2.
Procalcitonin (PCT), recognised as a marker of sepsis, was investigated in a porcine model of endotoxic shock. The results showed that continuous IV infusion (1-4 h) of LPS (40 μg/kg) in pigs was able to induce a generalised increase of PCT expression in lung, heart, kidney and liver. The increase in PCT was significant only in kidney and was accompanied by an increase in IL-6 gene expression. In vitro results demonstrated that peripheral blood mononuclear cells (PBMCs), as well as endothelial cells, were potentially capable of contributing to in vivo extrathyroidal PCT production. These findings support previous data from pigs concerning the occurrence of widespread activation of PCT extrathyroidal gene expression during endotoxic shock in pigs. Nevertheless, the levels of PCT detected were very low, suggesting the need for additional studies to validate the pig as a reliable animal model for investigating the role of PCT in sepsis.  相似文献   
3.
Artificial insemination is extensively performed in pig farms in Europe, the United States and Canada. Antibiotics are typically added to the inseminating dose to limit bacterial growth during liquid phase storage at 16°C, as bacterial contamination is unavoidable. The World Organization for Animal Health (OIE) and the Food and Agriculture Organization (FAO) take action to control and reduce antibiotic use in animals as more bacteria are becoming resistant to antimicrobials. To avoid the use of antibiotics, we prepared inseminating doses using microfiltered seminal plasma (SP). Microfiltration is a common technology used to reduce bacterial contamination but may retain seminal substances, influencing sperm quality during storage. Therefore, the aim of this study was to evaluate the morphofunctional parameters of spermatozoa during storage at 16°C in doses prepared with or without microfiltered SP, with or without the addition of antibiotics, in a Latin square design. Artificial insemination doses with microfiltered SP and without antibiotic addition preserved spermatozoa viability, mitochondrial membrane potential, acrosome integrity and objective motility, with absolute values equal or even better than those observed in conventional doses. In conclusion, although the results could be considered preliminary due to the small sample size, this study suggests that microfiltration of SP can be a simple method, feasible on farms, to replace antibiotic use in extended doses stored in the liquid phase at 16°C for up to 7 days.  相似文献   
4.
In equine management, it is important to predict the approximate foaling date of mares to monitor parturition and allow early identification and intervention of problems during the perinatal period. There are no studies comparing accurate gestational length (GL) when mares are carrying mule foals and no controlled comparisons between GL of mares pregnant with equine or mule foals. Therefore, the objectives of this study were to compare GL of mares pregnant with equine or mule foals and establish normal reference values for GL of mares pregnant with male and female mules. Gestational length of Mangalarga Paulista breed mares pregnant with equine (n = 54) or with mule (n = 54) foals during the breeding seasons of 2007 to 2016 was evaluated. The mean GL was 347.2 ± 1.4 days (range of 326–368 days) and 341.1 ± 1.6 days (range of 307–360 days) for equine and mule pregnancies, respectively. The normal GL reference for mule pregnancies was 316.9–365.3 days. Therefore, GL of equine pregnancies was longer than of mule pregnancies. Gestational length was not different when pregnancies resulted in females or males within each group. This study established an important reference value for normal GL of mule pregnancies, which can be used by practitioners to estimate and predict foaling dates more accurately.  相似文献   
5.
Veterinary Research Communications - Ribeiro, L.A., Turba, M.E., Bernardini, C., Zannoni, A., Bacci, M.L. and Forni, M., 2007. Matrix metalloproteinases -2 and -9 in swine luteal tissue...  相似文献   
6.
An incompetent vulvar seal leads to reproductive failure, and a surgical intervention might be required. The present paper describes modifications to Pouret's surgery. We suggest the use of a simple interrupted vertical mattress suture, which avoids seroma. Eighteen Brazilian Jumping Horse mares, older than 20 years and barren for 3-5 consecutive years, underwent modified Pouret's surgery. A horizontal skin incision of 3-4 cm was made half way between the anus and upper commissure of the vulva. The submucosal and connective tissue were dissected, and the rectovaginal shelf was split horizontally by sectioning the muscular and ligamentous connections between the anus, vulva, caudal portion of the rectum, and vagina until the vulva was oriented vertically. The wound was changed from a horizontal plane to a vertical plane by placing the suture vertically using approximately eight interrupted U sutures distributed in two layers with polyamide thread. The modified Pouret's surgical technique provided a perfect coaptation of the vulvar lips and a correct perineal position. Those mares that presented with horizontally tipped vulvar lips due to advanced age and stretching of the pelvic tissues by multiple foaling had their vulvas replaced. Also, the surgical procedure was easy to perform. As to fertility, of the 18 initial mares, 14 were inseminated, and all became pregnant. Thus, it was possible to conclude that the anatomical changes performed throughout the surgical procedure predisposed to a better vulvar coaptation, correcting the pneumovagina.  相似文献   
7.
8.
This study was aimed at assessing the capability of semen experimentally infected with porcine circovirus type 2 (PCV2) to produce porcine blastocysts PCR positive for PCV2. Embryos were obtained from in vitro maturation (IVM) and in vitro fertilization (IVF) of porcine oocytes or by parthenogenesis. Sperm suspension was exposed to PCV2b and utilized for IVF. PCV2 spiked semen did not reveal any reduction in sperm viability or motility but its ability to produce infected blastocysts was irrelevant as only one out of 15 blastocysts obtained by IVF were PCV2b; however two blastocysts were PCV2a positive. Furthermore, the presence of PCV2 was demonstrated also in embryos obtained by parthenogenesis (one out of 17 was PCV2b and one PCV2a positive). Even if PCV2 firmly attaches to the surface of spermatozoa, experimentally spiked sperm were not effective in infecting oocytes during IVF and in producing PCR positive embryos. The infected blastocysts we obtained derived most probably from infected oocytes recovered at the abattoir.  相似文献   
9.
Cork oak landscape dynamics were assessed over a 47-year period (1958–2005) in an endangered region of southwest Portugal using a GIS approach. The area of cork oak woodlands was maintained during this period, but shifts due to land abandonment were evident leading to transformation of cork oak agriculture areas into woodlands and of cork oak woodlands into shrublands (average yearly change rates of 0.6 and 0.1%, respectively). The multi-temporal landscape analyses showed that expansion and regression rates of cork oak forests were similar (15 and 16 ha year−1, respectively). The main factor determining oak woodlands expansion and regression was related to land-use changes, but slope, aspect and soil type were also significant factors. The substitution of agriculture lands and oak woodlands by shrublands has a determining role in periods of disturbance and recovery of these Mediterranean ecosystems.  相似文献   
10.

Objective

The aim of this study was to validate the Italian version of the UNESP–Botucatu Unidimensional Composite Pain Scale (UCPS-IV) for assessing postoperative pain in cattle.

Study design

Video analysis and psychometric testing.

Animals

A total of 40 Nellore cattle, age 2–3 years, weighing 365 ± 51 kg.

Methods

An English version of the scale was translated to Italian and back translated to English to ensure semantic equivalence. A total of four Italian observers and the researcher who developed the original scale (considered as the gold standard) analysed videos of 40 cattle previously subjected to orchiectomy (recorded for each cattle at four predetermined timepoints during the perioperative period) unaware of the videos’ timepoint. They assigned a pain score [ranging from no pain (0) to severe pain (10)] using the Italian version of the scale and verified the need for analgesic treatment for each animal. The obtained scores were subjected to psychometric validity, responsiveness and reliability tests.

Results

The factor analysis of the scale resulted in a one-factor solution. Significant changes in pain scores in response to surgery and analgesics confirmed not only the content and construct validity, but also responsiveness. The agreement between the researcher who developed the original scale and the blinded observers and the correlation between the pain scores determined by the scale and those determined by three classical unidimensional pain scales confirmed criterion and concurrent validity. Internal consistency of the scale was excellent. Inter- and intrarater reliability ranged from moderate to good and from moderate to very good for all scale items, respectively, supporting reproducibility and stability. The cut-off point for rescue analgesia calculated by the receiver operating characteristic curve was > 3.

Conclusions and clinical relevance

The results confirm that the UNESP–Botucatu UCPS-IV appears to be a valid and reliable tool for the assessment of postorchiectomy pain in the bovine species. The determination of a cut-off point for rescue analgesia is also helpful for guiding analgesic therapy.  相似文献   
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