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Short-term heart-rate variability in healthy small and medium-sized dogs over a five-minute measuring period Texto completo
2020
Baisan, Radu Andrei | Condurachi, Eusebiu Ionuț | Vulpe, Vasile
Five-minute heart-rate variability (HRV) measurement is a useful tool for assessing the autonomic nervous system (ANS) balance in humans, but there are no studies on healthy dogs. The aim of the study was, therefore, to provide the reference ranges in small and medium-sized breeds for short-term HRV time and frequency domain (TFD) analyses. A total of 79 healthy dogs were included in the study between 2015 and 2019. Grouping by age with the breakpoint at six years and subgrouping by reproductive status and sex was imposed. All the dogs were included after physical and cardiological examinations and blood analyses. The TFD of HRV were analysed from a five-minute-long digital ECG recording after removal of non-sinus complexes. There were no statistically significant differences in any TFD parameters between age, reproductive status or sex groups. A mild increase in all time domain parameters and the high-frequency (HF) band was observed in older dogs, and the low frequency (LF):HF ratio decreased in these dogs. In males, the time domain parameters and HF band increased slightly. The normal ranges for HRV derived from short-term ECG recording in the usual clinical environment now have proposed reference ranges. Our findings suggest that accommodation time, age, sex, or reproductive status do not influence the results derived from these recordings, indicating that this method is reliable for assessing the ANS function in small and medium-sized dog breeds.
Mostrar más [+] Menos [-]Effects of Sunset Yellow FCF on immune system organs during different chicken embryonic periods Texto completo
2020
Çolakoğlu, Fatma | Selçuk, Muhammet Lütfi
Sunset Yellow FCF (SY), used frequently in ready-made foods, cosmetics, and the pharmaceutical industry, may cause many health problems. This study is intended to evaluate the morphological and cellular effects of SY on the embryonic chicken immune system throughout incubation. Babcock white leghorn eggs were randomly divided into four groups. Besides a control group, there were three treatment groups which received a single injection of 200, 1,000, or 2,000 ng of SY into the air sac just before incubation. The eggs were opened on the 10ᵗʰ, 13ᵗʰ, 16ᵗʰ, and 21ˢᵗ days of incubation. Samples of the bursa of Fabricius, thymus, and spleen were taken from embryos. Serial sections of 5 μm thickness were stained with histological methods and routine histological procedures were performed. An increase in the spleen volume was determined as the hatching time of the chicks approached. The highest eosinophil ratio was found in the SY₁,₀₀₀ and SY₂,₀₀₀ groups (P < 0.05), where the most significant change was developmental retardation in the thymus. In the bursa of Fabricius, there was less lymphocyte accumulation and eosinophilic cell infiltration with increasing doses. It was concluded that in ovo administered SY has undesired effects on embryonic development of the bursa of Fabricius, spleen, and thymus, and on spleen volume.
Mostrar más [+] Menos [-]Therapeutic effects of revascularisation on the healing of free bone grafts in dogs Texto completo
2020
Zheng, Jia-San | Ruan, Hong-Ri | Shuang-Qiu, | Jing-Nie, | Hou, Kai-Wen | Rui-Wu,
The therapeutic effect of subcutaneous embedding and revascularisation on the repair of canine bone defects caused by open fracture was examined. A total of 12 adult beagle dogs were randomly split into a control group (group C) and a test group (group T). A section of the radius was removed from each dog under general anaesthesia and the deficit supported by an orthopaedic implant. Group T had the section surgically implanted next to the blood vessel–rich saphenous vein and Group C had it cryopreserved at −80°C. After eight weeks, the bone was surgically implanted back into the matching radial deficit. Bone healing was evaluated by gross morphological and X-ray examinations, post-mortem histology, and successive blood measurements of key bone biochemical markers. At 12 weeks, the bone healing boundary was disappearing more quickly in group T dogs than in their group C counterparts. X-ray and histological examinations showed that the cortical repair of group T subjects was complete and the bony plate arrangement was more regular than that in group C. The levels of bone biochemical markers also proved that the healing state of group T was better. The results showed that the degree of healing, osteoclast activity, and bone formation status of group T were better than those of group C, proving that the vascularised bone graft had a significantly shorter healing time than the cryopreserved bone graft.
Mostrar más [+] Menos [-]Porcine epidemic diarrhoea virus induces cell-cycle arrest through the DNA damage-signalling pathway Texto completo
2020
Luo, Yi-Ran | Zhou, Shu-Ting | Yang, Liang | Liu, Yuan-Ping | Jiang, Sheng-Yao | Dawuli, Yeliboli | Hou, Yi-Xuan | Zhou, Tian-Xing | Yang, Zhi-Biao
Porcine epidemic diarrhoea virus (PEDV) infection causes watery diarrhoea, vomiting, anorexia, and weight loss, especially among neonatal piglets, inflicting on them morbidity and mortality potentially reaching 90%–100%. Despite it being known that certain mammalian cell phases are arrested by PEDV, the mechanisms have not been elucidated, and PEDV pathogenesis is poorly understood. This study determined the effect of an epidemic PEDV strain on cell cycle progression. We observed the effect of the PEDV SHpd/2012 strain on an infected Vero cell cycle through flow cytometry and Western blot, investigating the interrelationships of cell-cycle arrest, the DNA damage–signalling pathway caused by PEDV and the phosphorylation levels of the key molecules Chk.2 and H2A.X involved upstream and downstream in this pathway. PEDV induced Vero cell-cycle arrest at the G1/G0 phase. The phosphorylation levels of Chk.2 and H2A.X increased with the prolongation of PEDV infection, and no significant cell-cycle arrest was observed after treatment with ATM or Chk.2 inhibitors. The proliferation of PEDV was also inhibited by treatment with ATM or Chk.2 inhibitors. PEDV-induced cell-cycle arrest is associated with activation of DNA damage–signalling pathways. Our findings elucidate the molecular basis of PEDV replication and provide evidence to support further evaluation of PEDV pathogenesis.
Mostrar más [+] Menos [-]Effects of vitamin C supplementation on the blood oxidative stress and antibody titre against Histophilus somni vaccination in calves Texto completo
2020
Otomaru, Konosuke | Oishi, Shoko | Fujimura, Yu | Iwamoto, Yuki | Nagai, Katsuhisa | Ijiri, Moe
The purpose of this study was to determine the effects of vitamin C supplementation on blood oxidative stress biomarkers and antibody response to vaccination in calves. Thirty-four clinically healthy 2 week old Japanese Black calves were randomly assigned to two groups. Seventeen calves formed the VC group which received 1,000 mg of vitamin C daily from 2 to 8 weeks of age, and the other 17 calves of the control group did not receive supplementation. All calves received an inactivated Histophilus somni vaccine at 4 and 8 weeks of age. Blood samples were taken at 2, 4, 8 and 12 weeks of age. The concentration of the serum reactive oxygen metabolites (d-ROMs), and the oxidative stress index (OSI), which is calculated from the d-ROMs and biological antioxidant potential, were significantly lower at 8 weeks of age in the VC group than in the control group (P < 0.05). The antibody titres to H. somni in the VC group were significantly higher than those in the control group at 12 weeks of age after the second vaccination (P < 0.05). Vitamin C supplementation to calves may reduce oxidative stress and enhance the antibody production after vaccination with H. somni.
Mostrar más [+] Menos [-]Seroprevalence and distribution of leptospiral serovars in livestock (cattle, goats, and sheep) in flood-prone Kelantan, Malaysia Texto completo
2020
Sabri Abdul Rahman, Mohammad | Khairani Bejo, Siti | Zakaria, Zunita | Hassan, Latiffah | Azri Roslan, Mohd
Leptospirosis is a bacterial disease that affects both humans and animals, the occurrence of which increases markedly during and after heavy rainfall and flooding. The aim of this study was to determine the serological prevalence of leptospiral infection in livestock after a voluminous flood in 10 districts of the Malaysian state of Kelantan. In December 2014, Kelantan was hit by an extensive flood. A total of 1,728 serum samples were collected from livestock from the state, comprised of 1,024 from cattle, 366 from goats and 338 from sheep, and they were tested using the microscopic agglutination test (MAT). Altogether, 203 (11.75%; 203/1728; 95% CI: 10.20%–13.30%) of the tested sera were found to be positive serologically. Cattle had the highest prevalence of 14.16% (145/1024), while goats and sheep had 11.20% (41/366) and 5.03% (17/338) respectively. The most frequent serovars detected were Hardjo-bovis (3.70%; 64/1728), Hebdomadis (2.08%; 36/1728) and Pomona (1.04%; 18/1728). There was a statistically significant association (P < 0.05) between livestock that were exposed to the flood and seropositivity. This study showed that flood is a risk factor that can play a role in the epidemiology of leptospiral infection in livestock.
Mostrar más [+] Menos [-]Metagenomic analysis of acquired antibiotic resistance determinants in the gut microbiota of wild boars (Sus scrofa) – preliminary results Texto completo
2020
Libisch, Balázs | Keresztény, Tibor | Kerényi, Zoltán | Kocsis, Róbert | Sipos, Rita | Papp, Péter P. | Olasz, Ferenc
Land application of manure that contains antibiotics and resistant bacteria may facilitate the establishment of an environmental reservoir of antibiotic-resistant microbes, promoting their dissemination into agricultural and natural habitats. The main objective of this study was to search for acquired antibiotic resistance determinants in the gut microbiota of wild boar populations living in natural habitats. Gastrointestinal samples of free-living wild boars were collected in the Zemplén Mountains in Hungary and were characterised by culture-based, metagenomic, and molecular microbiological methods. Bioinformatic analysis of the faecal microbiome of a hunted wild boar from Japan was used for comparative studies. Also, shotgun metagenomic sequencing data of two untreated sewage wastewater samples from North Pest (Hungary) from 2016 were analysed by bioinformatic methods. Minimum spanning tree diagrams for seven-gene MLST profiles of 104 E. coli strains isolated in Europe from wild boars and domestic pigs were generated in Enterobase. In the ileum of a diarrhoeic boar, a dominant E. coli O112ab:H2 strain with intermediate resistance to gentamicin, tobramycin, and amikacin was identified, displaying sequence type ST388 and harbouring the EAST1 toxin astA gene. Metagenomic analyses of the colon and rectum digesta revealed the presence of the tetQ, tetW, tetO, and mefA antibiotic resistance genes that were also detected in the gut microbiome of four other wild boars from the mountains. Furthermore, the tetQ and cfxA genes were identified in the faecal microbiome of a hunted wild boar from Japan. The gastrointestinal microbiota of the free-living wild boars examined in this study carried acquired antibiotic resistance determinants that are highly prevalent among domestic livestock populations.
Mostrar más [+] Menos [-]Prevalence and characterisation of class 1 and 2 integrons in multi-drug resistant Staphylococcus aureus isolates from pig farms in Chongqing, China Texto completo
2020
Ye, Chao | Hou, Fengqing | Xu, Dongyi | Huang, Qingyuan | Chen, Xia | Zeng, Zheng | Peng, Yuanyi | Fang, Rendong
Integrons are mobile DNA elements that allow for acquisition and dissemination of antibiotic-resistance genes among pig farm-derived bacteria. Limited information is available on integrons of Staphylococcus aureus from pig farms. The aim of this study was to characterise and investigate the prevalence of class 1 and 2 integrons in multi-drug resistant (MDR) S. aureus isolates from pig farms. A total of 724 swabs were collected from 12 pig farms in Chongqing, China, and examined by conventional microbial and molecular methods. In total, 68 isolates were S. aureus, 57 of which were methicillin resistant (MRSA). All 68 isolates were MDR strains and carried integrons, of which 88.2% (60/68) harboured both class 1 and 2. In addition, 85.3% (58/68) of the class 2 integron-positive isolates carried the β-lactam resistance gene (blaTEM₋₁), and 66.7% (40/60) of the class 1 integron–positive isolates carried the aadA1c, aadA1 or dfrA1 gene for respective streptomycin and spectinomycin or trimethoprim resistance. Class 1 and 2 integrons are common among the pig farm-derived S. aureus isolates. On account of their significance for public health, the prevalence of the integrons and their associated resistance genes in pig farm-derived S. aureus isolates should be paid special attention.
Mostrar más [+] Menos [-]Oestrus synchronisation with progesterone-containing sponge and equine chorionic gonadotropin in Pirlak ewes during the non-breeding season: can Toryum improve fertility parameters? Texto completo
2020
Kuru, Mushap | Boga Kuru, Buket | Sogukpinar, Osman | Cebi Sen, Cigdem | Oral, Hasan | Kirmizibayrak, Turgut
The aim of the study was to determine the effect of the vitamins, omega-3 polyunsaturated fatty acid and minerals in the supplement Toryum administered before and during oestrus synchronisation on some fertility parameters of ewes during the non-breeding season. The experimental animals were clinically healthy Pirlak ewes, 55–75 days postpartum, aged 2–4 years and weighing 40–50 kg. A sponge was inserted into the vagina for 10 d (G1, n = 30; G2, n = 30) or 14 d (G3, n = 30; G4, n = 30) for oestrus synchronisation, and on the day of removal, 400 IU equine chorionic gonadotropin was injected. Toryum soft capsules were administered individually (1 capsule/ewe p.o.) to G1 and G3 ewes seven days before the sponge was inserted and on the day it was removed. Oestrus detection was started 12 h after sponge removal. Pregnancy was diagnosed by transrectal ultrasonography on the 30ᵗʰ day after mating. The pregnancy rate was statistically different between G1 and G4 (P < 0.05). The onset of oestrus was statistically different (P < 0.001) between the 10-d groups (G1 and G2) and the 14-d groups (G3 and G4). The litter size and oestrus, conception, lambing, multiple birth, and survival rates were not significantly different between the groups (P > 0.05). Toryum administered to Pirlak ewes during progesterone-based oestrus synchronisation protocols during the non-breeding season may increase pregnancy rates. The relationship between Toryum and fertility parameters in ewes would be better understood by comprehensive studies.
Mostrar más [+] Menos [-]Serum total antioxidant capacity and enzymatic defence of dogs with chronic heart failure and atrial fibrillation: a preliminary study Texto completo
2020
Michałek, Marcin | Tabiś, Aleksandra | Noszczyk-Nowak, Agnieszka
Atrial fibrillation may potentially contribute to oxidative stress to a greater extent than chronic heart failure. The aim of the study was to compare the serum total antioxidant capacity and enzymatic antioxidant defence of dogs with chronic heart failure and atrial fibrillation with those of subjects with chronic heart failure and sinus rhythm and healthy controls. A total of 33 dogs were divided into three groups: dogs with chronic heart failure and atrial fibrillation (CHF + AF; n = 12), chronic heart failure and sinus rhythm (CHF + SR; n = 9), and healthy controls (n = 12). Serum total antioxidant capacity (TAC), serum CuZn-superoxide dismutase (SOD) and catalase, and plasma glutathione peroxidase (GPx) activity were determined. SOD activity and serum TAC were significantly lower in the study groups than in control animals. Catalase activity was significantly higher and plasma GPx activity significantly lower in dogs with CHF + AF compared with the CHF + SR and control dogs. The results suggest that chronic heart failure in dogs significantly impacts the serum TAC and the antioxidant enzymatic defence, while plasma GPx activity is markedly lower in dogs with chronic heart failure and atrial fibrillation. The role of that imbalance needs further investigation.
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