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991.
Diego F. Varela-Ortiz José E. Barboza-Corona Joaquín González-Marrero Ma. Fabiola León-Galván Mauricio Valencia-Posadas Alma A. Lechuga-Arana Cynthia G. Sánchez-Felipe Fernanda Ledezma-García Abner J. Gutiérrez-Chávez 《Veterinary research communications》2018,42(3):243-250
Staphylococcus aureus is an opportunistic pathogen that may cause severe infections in livestock, and represents the major cause of mastitis in dairy cows. Currently, instead of using antibiotics, new strategies are sought to reduce this clinical health problem. The aim of this study was to determine the efficacy of phage therapy to kill S. aureus strains obtained from farms located at the State of Guanajuato, México. Thirty-six S. aureus strains from cow milk with subclinical mastitis were isolated and identified, and the susceptibility to antibiotics and four phages also isolated in this work was tested. It was found that more of 90% of S. aureus isolates were not susceptible to six or more antibiotics, and 100% were resistant to penicillin, dicloxacillin, cefotaxime, ampicillin and cephalothin, and 81 and 77%, to tetracycline and cefuroxime, respectively. Fortunately, 100% of S. aureus isolates were susceptible to phages used in this work, which was detected as clear zones using specific phage. It was shown for the first time, that phages used in this study are active against pathogenic S. aureus and might be incorporated into the therapy as an important tool for the control of staphylococcal bovine mastitis, specially to antibiotic-resistant S. aureus strains isolated in farm located at the state of Guanajuato, México; and its use might be extended to other regions inside or outside the country. 相似文献
992.
993.
Unraveling avian and reptilian hematology: An optical and electron microscopic study of the buffy coat
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Filipe Fontes Pinto Célia Lopes Fernanda Malhão Ricardo Marcos 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2018,47(3):407-414
Background
Blood centrifugation and buffy coats are at the cornerstone of hematology. In mammals, the buffy coat has a layered disposition (from bottom to top) with neutrophils on top of erythrocytes, followed by monocytes/lymphocytes, and platelets. In nonmammals, this distribution is unknown. Recently, the cell tube block (CTB) technique was developed to study the buffy coat, but it was never applied to nonmammal buffy coats.Objectives
This study aimed to evaluate using the CTB technique to study reptilian and avian buffy coats and to propose its use for clinical applications.Methods
Blood from five birds and eight reptiles of different species was obtained to make CTBs that were processed for optical/electron microscopy. H&E, Sirius red, and immunohistochemistry staining against CD3 (to label T lymphocytes) were applied to the CTBs.Results
In birds, the buffy coat had a layered appearance with the granulocyte layer containing granulocytes (heterophils and eosinophils) and nucleated erythrocytes followed by a mononuclear cell layer containing lymphocytes, monocytes, and thrombocytes. In some animals, a nucleated erythrocyte layer was observed admixed with the granulocyte/mononuclear cell layer. A small clot within the buffy coat was seen in seven reptiles, and less definition of layers occurred in reptiles, with only one or two layers. Lymphocytes appeared toward the top of the buffy coat.Conclusions
From a comparative hematology perspective, the buffy coat of mammals differs from that of birds and more from that of reptiles. The CTB technique can be used to study these differences in avian and reptilian hematology, especially to study atypical circulating cells, hemoparasites, or blood cell proportions in health and disease. 相似文献994.
Relationships among neuroscore,magnetic resonance imaging features,and intracranial pressure in sheep affected by slow‐growing brain lesions
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Maria A. Evangelisti Roberta Deiana Valentino Melosu Giovanni P. Burrai Isabella Ballocco Antonio Varcasia Antonio Scala Maria L. Manunta 《Veterinary radiology & ultrasound》2018,59(3):305-311
Diagnosing high intracranial pressure by clinical and diagnostic imaging is particularly challenging for chronic or slow‐growing lesions. The aim of this prospective case‐control study is to determine whether the neuroscore and brain magnetic resonance imaging (MRI) are related to the direct measurement of intracranial pressure in sheep affected by intracranial slow‐growing lesions due to chronic cerebral coenurosis (Coenurus cerebralis). Seventeen affected and 10 control sheep were included. All animals underwent a neurological examination, MRI of the brain, and direct measurement of intracranial pressure. The severity of clinical signs and MRI findings were scored. Data were statistically analyzed. The invasive intracranial pressure value was higher in affected animals. A severely altered neuroscore is related to an increased intracranial pressure beyond the normal threshold (P < 0.05). The volume of the calvarium was larger in affected animals than in control animals (P = 0.0001) and was positively influenced by the presence and volume of the parasitic cyst (r = 0.7881, P < 0.01). Several degrees of deviation and deformation of both the ventricular system and brain parenchyma were detected by MRI. Subjective MRI findings were not associated with intracranial hypertension. In conclusion, this study shows that in sheep affected by slow‐growing lesions, severe alterations in the neuroscore and the results of objective MRI are related to an increased intracranial pressure beyond the normal threshold. 相似文献
995.
Matheus V. L. Moreira Maria C. de Andrade Gustavo O. Fulgêncio Ingeborg M. Langohr Roselene Ecco 《Veterinary ophthalmology》2018,21(5):535-538
An indoor‐only, 5‐year‐old, spayed female domestic shorthair cat presented for an ophthalmic examination of the left eye. An intraocular tumor with secondary glaucoma and blindness was diagnosed; the globe was enucleated and sent for histopathological examination. Gross examination revealed a solid white mass filling the entire vitreous space and replacing the iris and ciliary body. The lens and retina appeared to be similarly replaced by the neoplasm. Histological examination revealed a complete loss of the internal ocular structures, with a ruptured capsule as the only remnant of the lens within an extensive malignant mesenchymal neoplastic cell proliferation. The cells were polygonal, with well‐defined cytoplasmic borders and abundant weakly basophilic cytoplasm, embedded within the islands of chondroid matrix. No neoplastic invasion of the sclera was apparent. The animal died 6 months after the enucleation due to respiratory distress. Gross examination revealed numerous firm, white to tan nodular masses with smooth to mildly irregular surfaces dispersed throughout the parietal pleura, thoracic surface of the diaphragm, tracheobronchial and mediastinal lymph nodes, pericardium, and lungs. On cross‐section, the neoplastic nodules were solid and variably translucent, resembling hyaline cartilage. Histologically, these nodules were similar to the neoplasm identified earlier in the left globe. Metastasis of post‐traumatic ocular chondrosarcoma has not yet been described in cats. This is therefore believed to be the first report of metastases of this type of neoplasm in cats. This case adds to the limited set of data on the outcome of this type of tumor. 相似文献
996.
Eugenio Gaudio Laura Voltan Giulia Maria De Benedictis 《Veterinary anaesthesia and analgesia》2018,45(3):351-356
Objective
To evaluate the clinical effects and quality of sedation, induction, maintenance and recovery in Lemur catta after dexmedetomidine–butorphanol–midazolam sedation and alfaxalone anaesthesia.Study design
Prospective, observational study.Animals
Six male L. catta weighing 3.0 ± 0.6 kg undergoing surgical castration.Methods
Lemurs were sedated with intramuscular dexmedetomidine (0.015 mg kg?1), butorphanol (0.2 mg kg?1) and midazolam (0.2 mg kg?1). Anaesthesia was induced with intravenous alfaxalone 0.5 mg kg?1 over 60 seconds; further boluses were administered until tracheal intubation was feasible and final dose recorded. Alfaxalone continuous infusion was used to maintain anaesthesia. Atipamezole (0.15 mg kg?1) was administered during recovery. The quality of sedation, induction, intubation, maintenance and recovery was assessed using a scoring system. Physiological parameters were recorded during sedation, maintenance and recovery.Results
Sedation was achieved in 13.6 ± 5.6 minutes and no reactions were observed during handling or venepuncture. The mean dose of alfaxalone required for induction and maintenance was 2.09 ± 0.65 and 0.08 ± 0.02 mg kg?1 minute?1, respectively. Quality of induction, intubation and maintenance was good in almost all animals. Mild self-limiting muscle twitching was observed after alfaxalone administration in three animals. Cardiorespiratory function was stable in all animals but one. One lemur showed respiratory depression and required oxygen administration and manual ventilation. The mean maintenance time was 29.2 ± 7.4 minutes. The mean times from the end of alfaxalone administration to extubation, atipamezole administration and full recovery were: 15.3 ± 8.0, 22.2 ± 4.6 and 60.0 ± 8.4 minutes, respectively. Recovery was considered good in all animals.Conclusions and clinical relevance
Dexmedetomidine–butorphanol–midazolam combination provided reliable sedation and adequate muscle relaxation in L. catta. Alfaxalone proved to be a useful drug for induction and maintenance of anaesthesia and might be considered an option for injectable anaesthesia in lemurs. 相似文献997.
Pawel Antoni Kolodziejski Maciej Sassek Daniela Chalupka Natalia Leciejewska Leszek Nogowski Pawel Mackowiak Damian Jozefiak Katarzyna Stadnicka Maria Siwek Marek Bednarczyk Tomasz Szwaczkowski Ewa Pruszynska-Oszmalek 《畜牧与生物技术杂志(英文版)》2018,(2)
Background: In order to discover new strategies to replace antibiotics in the post-antibiotic era in meat-type chicken production, two new synbiotics were tested:(Lactobacillus salivarius IBB3154 plus galactooligosaccharide(Syn1) and Lactobacillus plantarum IBB3036 plus raffinose family oligosaccharides(Syn2).Methods: The synbiotics were administered via syringe, using a special automatic system, into the egg air chamber of Cobb 500 broiler chicks on the 12 thday of egg incubation(2 mg of prebiotics + 105 cfu bacteria per egg).Hatched roosters(total 2,400) were reared on an experimental farm, kept in pens(75 animals per pen), with free access to feed and water. After 42 d animals were slaughtered. Blood serum, pancreas, duodenum and duodenum content were collected.Results: Syn2 increased trypsin activity by 2.5-fold in the pancreas and 1.5-fold in the duodenal content. In the duodenum content, Syn2 resulted in ca 30% elevation in lipase activity and 70% reduction in amylase activity.Syn1 and Syn2 strongly decreased expression of m RNA for GLP-1 and GIP in the duodenum and for GLP-1 receptors in the pancreas. Simultaneously, concentrations of the incretins significantly diminished in the blood serum(P 0.05). The decreased expression of incretins coincides with changed activity of digestive enzymes in the pancreas and in the duodenal content. The results indicate that incretins are involved in the action of Syn1 and Syn2 or that they may even be their target. No changes were observed in key hormones regulating metabolism(insulin, glucagon, corticosterone, thyroid hormones, and leptin) or in metabolic indices(glucose,NEFA, triglycerides, cholesterol). Additionally, synbiotics did not cause significant changes in the activities of alanine and aspartate aminotransferases in broiler chickens. Simultaneously, the activity of alkaline phosphatase and gamma glutamyl transferase diminished after Syn2 and Syn1, respectively.Conclusion: The selected synbiotics may be used as in ovo additives for broiler chickens, and Syn2 seems to improve their potential digestive proteolytic and lipolytic ability. Our results suggest that synbiotics can be directly or indirectly involved in incretin secretion and reception. 相似文献
998.
Valentina Stefanetti Agnese Compagnone Chiara Sordini Fabrizio Passamonti Elisa Rampacci Livia Moscati Maria Luisa Marenzoni 《Topics in companion animal medicine》2018,33(4):122-125
Abortion and neonatal mortality are events that can occur in breeding bitches and queens. It has been reported that up to 55% and 33% of these cases remain without a known cause, respectively, in canine and feline pregnancies. Unusual abortigenic and potentially zoonotic agents, including Coxiella burnetii and Leptospira spp., may be involved in these cases. C. burnetii is able to cause reproductive disorders in cattle, sheep and goats, and cases of abortion have been observed in dogs and cats. Moreover, several outbreaks of C. burnetii infection in humans have been caused by delivering bitches and queens, and some of these animals experienced abortion. Leptospira interrogans sensu lato is able to cause abortion or stillbirth in several animal species and its abortigenic role has occasionally been described in bitches and queens. The aim of this study was to search for C. burnetii and Leptospira spp. DNA in a retrospective series of 103 cases of canine and feline abortion, stillbirth, and neonatal mortality submitted for the identification of possible infectious agents. One hundred and fifty-one specimens were tested using PCR assays and found negative for C. burnetii and Leptospira DNA. However, in 49 samples (47.6%) other infectious causes of abortion, stillbirth, and neonatal mortality were identified. These results showed that C. burnetii and Leptospira spp. are probably not common abortigenic agents or causes of neonatal deaths in dogs. However, given the potential abortigentic and zoonotic role of these agents, surveillance of canine and feline abortion, stillbirth, and neonatal mortality could be advisable for a systematic investigation of these events. 相似文献
999.
1000.
Phosphorus Budget in Integrated Multitrophic Aquaculture Systems with Nile Tilapia,Oreochromis niloticus,and Amazon River Prawn,Macrobrachium amazonicum
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Fernanda S. David Danilo C. Proença Wagner C. Valenti 《Journal of the World Aquaculture Society》2017,48(3):402-414
Integrated multitrophic aquaculture (IMTA) systems are designed mainly for efficient use of resources. Substrates added to aquaculture ponds provide space for periphyton to settle and recover nutrients, making these nutrients available to the species being reared. The present study is centered on the phosphorus budget, analyzing the main ecological compartments of IMTA systems in earthen ponds stocked with Amazon River prawn, Macrobrachium amazonicum, and Nile tilapia, Oreochromis niloticus, with or without different added substrates. The experimental design was completely randomized, with three treatments (without a substrate, with a geotextile fabric substrate, and with a bamboo substrate) and four replications. Phosphorus entered the systems mainly in tilapia feed (ca. 50–61%), inlet water (ca. 17–27%), and fertilizer (ca. 6–7%). Input of phosphorus from other compartments ranged from 1.5 to 1.9%. Most phosphorus was accumulated at the pond bottom as sediment (ca. 60–68%) and fish biomass (ca. 18–26%), or discharged in the outlet water (ca. 7–10%). Feeding is the main driver for the distribution of phosphorus in the ponds. Levels of phosphorus retained in reared animals (20–28%) were higher in these IMTA systems than in tilapia and prawn monocultures (reported as 10–20% and 10–13%, respectively). Nonetheless, the present data showed that the addition of different types of substrates might not improve the recovery of phosphorus in animal biomass as initially supposed. Even so, these IMTA systems decreased the amount of phosphorus released in effluents, and this decrease was enhanced by the addition of substrates, reducing the impact on the receiving waterbodies. 相似文献