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141.
The aim of the present study was to evaluate anti-Neospora caninum antibodies and the vertical transmission rate in naturally infected pregnant zebu beef cows (Bos indicus) reared on pasture. The present study began with 200 cows from four farms (50 cows from each farm), and these animals were submitted to timed artificial insemination (TAI). After ultrasonography, 76 pregnant cows were selected, 22, 15, 22, and 17, respectively, from farms 1, 2, 3, and 4. Blood samples were taken from cows thrice during the first, second, and third trimester of gestation, and a blood sample was collected from 31 calves before colostrum milking. From 76 cows 23 (30.3%) had anti-N. caninum antibodies detected by indirect ELISA (Idexx), and 53 (69.7%) did not. Sixty-four cows that initiated the experiment were negative to N. caninum and 11 became positive either during the second or third trimester of gestation, this mean an infection incidence of 17.2% (11/64). OD for ELISA was higher (OD = 2.08) during the second and third (OD = 2.10) trimesters of pregnancy when compared with the first (OD = 1.81), however, there were no statistical differences (P = 0.45). The vertical transmission was calculated to be 29.0% (9/31), and the risk of vertical transmission of N. caninum in seropositive dams was 26.25 times higher than seronegative animals (OR = 26.25, 2.38 < OR < 289, P = 0.007). In conclusion, the rate of vertical transmission of N. caninum in pregnant zebu beef cows was 29%, and the risk was 26.25 higher in seropositive dams relative to than seronegative animals.  相似文献   
142.
The swine-origin pandemic (p) H1N1 influenza A virus causes mild upper-respiratory tract disease in most human patients. However, some patients developed severe lower-respiratory tract infections with fatal consequences, and the cause of these infections remain unknown. Recently, it has been suggested that different populations have different degrees of susceptibility to pH1N1 strains due to host genetic variations that are associated with inappropriate immune responses against viral genetic characteristics. Here, we tested whether the pathologic patterns of influenza strains that produce different disease outcomes in humans could be reproduced in a ferret model. Our results revealed that the severities of infection did not correspond to particular viral isolate and were not associated with the clinical phenotypes of the corresponding patients. Severe pathological outcomes were associated with higher viral replication, especially in alveolar areas, and with an exacerbated innate cellular immune response that was characterised by substantial phagocytic and cytotoxic cell migration into the lungs. Moreover, detrimental innate cellular responses were linked to the up-regulation of several proinflammatory cytokines and chemokines and the down-regulation of IFNα in the lungs. Additionally, severe lung lesions were associated with greater up-regulations of pro-apoptotic markers and higher levels of apoptotic neutrophils and macrophages. In conclusion, this study confirmed that the clinicopathological outcomes of pH1N1 infection in ferrets were not only due to viral replication abilities but also depended on the hosts’ capacities to mount efficient immune responses to control viral infection of the lung.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0085-8) contains supplementary material, which is available to authorized users.  相似文献   
143.
The Rabbit Hemorrhagic Disease Virus (RHDV) induces a severe disease that fulfils many requirements of an animal model of fulminant hepatic failure. However, a better knowledge of molecular mechanisms contributing to liver damage is required, and it is unknown whether the RHDV induces liver autophagy and how it relates to apoptosis. In this study, we attempted to explore which signalling pathways were involved in the autophagic response induced by the RHDV and to characterize their role in the context of RHDV pathogenesis. Rabbits were infected with 2 × 104 hemmaglutination units of a RHDV isolate. The autophagic response was measured as presence of autophagic vesicles, LC3 staining, conversion of LC3-I to autophagosome-associated LC3-II and changes in expression of beclin-1, UVRAG, Atg5, Atg12, Atg16L1 and p62/SQSTM1. RHDV-triggered autophagy reached a maximum at 24 hours post-infection (hpi) and declined at 30 and 36 hpi. Phosphorylation of mTOR also augmented in early periods of infection and there was an increase in the expression of the endoplasmic reticulum chaperones BiP/GRP78, CHOP and GRP94. Apoptosis, measured as caspase-3 activity and expression of PARP-1, increased significantly at 30 and 36 hpi in parallel to the maximal expression of the RHDV capsid protein VP60. These data indicate that RHDV infection initiates a rapid autophagic response, perhaps in an attempt to protect liver, which associates to ER stress development and is independent from downregulation of the major autophagy suppressor mTOR. As the infection continues and the autophagic response declines, cells begin to exhibit apoptosis.  相似文献   
144.
145.
Testicular vitrification is an alternative to preserve the genetic material of pre-pubertal animals. However, there are few studies on post-vitrification warming. Hence, the aim was to compare the influence of different warming temperatures on vitrified testicular fragments from pre-pubertal cats. The testicles were fragmented and divided into a control group (non-vitrified) and vitrified, using an association between dimethylsulphoxide and glycerol. The vitrified fragments were warmed at 50, 55 and 60°C/5 s. Morphological and morphometric evaluations were carried out using classical histology. Afterwards, the mitochondrial activity was evaluated using Rhodamine 123. The data were expressed in mean and standard error. The differences were considered significant when p < .05. In the histomorphological analysis, the testicular fragment presented seminiferous tubules with poorly developed germinal epithelium, compatible with pre-pubertal animals. The group warmed at 50°C presented similar to the control regarding the maintenance of the integrity of the tubules and cells, without stromal rupture and lamina propria alteration, as well as regarding the maintenance of the junctions between the cells. The group warmed at 55°C showed reduction of the cell junctions, and the one warmed at 60°C had increased detachment of the basement membrane (p < .05). The warming caused a reduction in the tubular diameter inversely proportional and progressive to the increase in temperature, with the highest diameter in the control group and the lowest in the 60°C group. The control group showed a lower incidence of Rhodamine 123, followed in ascending order of the warmings at 55 and 60°C. The higher mitochondrial activity was obtained with 50°C, showing an increase of the metabolic cell function at this temperature. It was concluded that the testicular fragment of pre-pubertal cats presents a better preserved morphology, morphometry and viability when warmed at 50°C.  相似文献   
146.
The objective of this study was to describe the clinical findings, medical management, and outcomes of horses with sabulous cystitis, and to describe a high flow bladder lavage procedure in horses that are standing or under general anesthesia. The medical records of 13 horses diagnosed with sabulous cystitis via cystoscopy between 2013 and 2020 were reviewed. Geldings (92%) and Warmbloods (46%) were overrepresented. The most common presenting complaint was urinary incontinence (69%). Complete blood cell count, serum biochemistry profile and urine cytology results were non-specific. Six (46%) horses had various degrees of erosion, ulceration, and hemorrhage of the bladder mucosa. All horses were treated with bladder lavage either with standing sedation (n = 12) or general anesthesia (n = 2), as well as antimicrobials (54%), anti-inflammatory drugs (62%), bethanechol (15%), and phenazopyridine (15%). Most horses (85%) were discharged from the hospital, but only a small percentage (23%) was reported as having no urinary abnormalities on follow-up communication.Key clinical message:Copious bladder lavage with a high flow rate system could mitigate the acute clinical signs and improve the quality of life of horses with sabulous cystitis, but the prognosis for return to previous level of athletic performance and long-term survival is guarded.  相似文献   
147.
Veterinary Research Communications - Coronavirus disease-19 (COVID-19) is caused by the severe acute Respiratory syndrome coronavirus-2 (SARS-CoV-2), which has become unstoppable, spreading rapidly...  相似文献   
148.
Our aim with this study was to evaluate the consumption, performance, quantitative characteristics of carcasses, biochemical profile, plasma levels of ghrelin and leptin, expression of the receptor for ghrelin (GHS-R1a) in the hypothalamus and duodenum, and the number of goblet cells in the duodenum of calves subjected to milk volume restriction and supplemented with 2-hydroxy-4-(methylthio)butanoic acid (HMTBa). We used 21 Holstein mixed-breed calves, aged between 3 and 15 d with an average weight of 36.8 kg, and housed in pens with troughs for hay, concentrate, and water. The study included two consecutive experimental periods (first period [P1] and second period [P2]) of 21 d each, with 7 d of adaptation to the diet and facilities. The calves were distributed in a completely randomized design in three treatments with seven repetitions. 1) Control: 6 liters of milk/d during P1 and 6 liters of milk/day during P2; 2) RES (milk restriction): 3 liters of milk/day during P1 and 6 liters of milk/day during P2; and 3) RES + HMTBa: 3 liters of milk/day during P1 and 6 liters of milk/day during P2 + 3.3 g of HMTBa/day in both periods. HMTBa was supplied in milk, and the amount of concentrated ration and hay provided and leftovers were recorded daily to estimate dry matter (DM) and crude protein consumption. Mean daily weight gain (DWG), final weight (FW), and feed conversion (FC) were obtained at the beginning and at the end of each 21-d period. Plasma concentrations of ghrelin and leptin, triglycerides, total protein, urea, lactate, creatinine, alkaline phosphatase, and cholesterol were measured for P1 and P2 at the end of each 21-d period. At the end of P2, animals were slaughtered; sections of the duodenum were collected to evaluate the expression of GHS-R1a and quantity of goblet cells; hypothalamus was used to evaluate the expression of GHS-R1a; rumen was used to evaluate the thickness of epithelium and keratin and the density, height, and width of ruminal papillae. In P1, total DM consumption, FW, DWG, glucose, and triglycerides were lower in the RES and RES + HMTBa groups (P < 0.001). In P2, there was an improvement in the FC of the RES + HMTBa group (compared with Control and RES groups) and a lower urea concentration in the RES group (compared with Control and RES + HMTBa groups) (P < 0.001). No differences were observed among groups regarding hormonal concentrations, histological parameters, and GHS-R1a expression in the duodenum and hypothalamus. Therefore, milk restriction combined with HMTBa supplementation promoted greater compensatory gain by a mechanism independent of changes in GHS-R1a expression and hormone levels of ghrelin and leptin.  相似文献   
149.
Soil organic carbon (SOC) is subject to relatively rapid changes. In grasslands soils, the management system influences these changes. Therefore, these soils play a crucial role in climate change mitigation. Current research has developed strategies and methodologies to help us understand their role as a carbon sink. In this study, the SOC and total nitrogen contents and stocks (SOC‐S) and their variation with depth were evaluated in annual crop rotations (cereal–fallow). Fifty soil profiles were sampled in the Los Pedroches Valley (southern Spain). This area consists of Mediterranean open rangelands—treeless grasslands with cereal–fallow rotation, under two management systems: long‐term (20 years) organic farming (OF) and conventional tillage (CT). The studied soils were Cambisols (CM), Leptosols (LP) and Luvisols (LV). The objective of this research was to determine any management system effects (OF vs CT) on SOC and total nitrogen contents and stocks and their variation with profile depth. It was observed that SOC concentration decreased with depth (Ah–Ap > Bw > C). The SOC concentration was higher in the top soil for all studied soils in OF compared with CT. The highest totals of SOC‐S were found in LV‐OF (66·01 Mg ha−1) and the lowest in LP‐CT (21·33 Mg ha−1). Significant differences (p < 0·05) between soils types and management practices were found in carbon stocks, increasing the SOC‐S in OF compared with that in CT in all studied soils; this increase was 75·25%, 85·73% and 234·88% for CM, LV and LP, respectively. The results indicated that management practices significantly influence SOC‐S in the Los Pedroches Valley and, consequently, OF in annual crop rotations (cereal–fallow) is an excellent alternative to CT that increases the SOC content in Mediterranean open rangelands—treeless grasslands environments. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
150.
Under semiarid climatic conditions, intensive tillage increases soil organic matter losses, reduces soil quality, and contributes to climate change due to increased CO2 emissions. There is a need for an agricultural management increasing soil organic matter. This paper presents the organic carbon (OC) and nitrogen (N) stocks, C:N ratio and stratification ratios (SRs) of these properties for olive groves soils under long‐term organic farming (OF), and conventional tillage (CT) in Los Pedroches valley, southern Spain. The results show that OF increased C and N stocks. The soil organic carbon (SOC) stock was 73·6 Mg ha−1 in OF and 54·4 Mg ha−1 in CT; and the total nitrogen (TN) stock was 7·1 Mg ha−1 and 5·8 Mg ha−1 for OF and CT, respectively. In the surface horizon (A: 0–16·9 cm in OF and Ap: 0–21·8 cm in CT) and Bw horizon (16·9–49·6 cm in OF and 21·8–56 cm in CT), SOC and TN concentrations and C:N ratios were higher in OF than in CT. Soil properties stratification in depth, expressed as a ratio, indicates the soil quality under different soil management systems. The SR of SOC ranged from 2·2 to 3·1 in OF and from 2·1 to 2·2 in CT. However, only SR2 (defined by Ap‐A/C) showed significant differences between CT and OF. The SR of TN showed similar trends to that of the SR of SOC. Organic farming contributes to a better soil quality and to increased carbon sequestration. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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