细化搜索
结果 441-450 的 483
Nanoparticles and their Potential Applications in Veterinary Medicine
2020
Eman Osama | Sawsan M.A. El-Sheikh | Mohammed H. Khairy | Azza A.A. Galal
Nanotechnology is the innovative and evolving technology with enormous potential for global revolutionization of animal sector. It offers the same opportunities for veterinarians as physicians, including therapy, diagnostics, tissue engineering, manufacturing of vaccines, and modern disinfectants. The nano-applications are already in use in animal health and production, animal husbandry and reproduction and animal nutrition. It has the ability for solving several problems associated with animal health. This review will throw the light on nanoparticles synthesis, classification, characterization, and their applications in veterinary field starting from medical applications to using the nanoparticles in animal nutrition and reproduction.
显示更多 [+] 显示较少 [-]Effect of topical administration of 0.1% diclofenac sodium ophthalmic solution at four frequencies on intraocular pressure in healthy Beagles
2020
Martabano, Brittany B. | De Linde Henriksen, Michala | Colussi, Jenny A. | Sharop, Julia L. | Wang, Zeke | Lappin, Michael R.
OBJECTIVE To evaluate effects of topical ophthalmic administration of diclofenac on intraocular pressure (IOP) when applied at 4 frequencies to eyes of Beagles. ANIMALS 8 ophthalmologically normal Beagles. PROCEDURES The study involved four 5-day experimental periods each separated by a 16-day washout period. During each period, 1 drop of 0.1% diclofenac sodium ophthalmic solution was administered to the right eye at 4 treatment frequencies (1, 2, 3, or 4 times/d); 1 drop of eyewash was administered to the left eye as a control treatment. A complete ophthalmic examination was performed on days 0 (day before first treatment) and 5 of each experimental period. Gonioscopy was performed on day 0 of the first period. The IOPs were measured at 7 am and 7 pm on days 1 through 5. RESULTS No abnormalities were detected during neuro-ophthalmic and ophthalmic examinations on day 0 of each experimental period. No adverse reactions to administration of diclofenac or eyewash were observed at any time point. No abnormalities were detected during ophthalmic examinations performed on day 5, and IOPs remained < 25 mm Hg in all 4 periods. No significant differences were identified between the treated and control eyes or among the 4 treatment frequencies. CONCLUSIONS AND CLINICAL RELEVANCE Topical ophthalmic administration of diclofenac up to 4 times/d in dogs with no ophthalmic abnormalities did not significantly increase the IOP. Additional research is needed to evaluate the effect of topical ophthalmic administration of diclofenac on IOP in dogs with anterior uveitis.
显示更多 [+] 显示较少 [-]Comparison of analgesic efficacy and fetal effects between transdermal administration of fentanyl and intramuscular administration of buprenorphine in pregnant sheep
2020
Padgett, Ashley L. | Lepiz, Mauricio L. | Mackay, Evelyn E. | Driskill, Austin J. | Ivanov, Ivan V. | Fajt, Virginia R. | Konarik, Megan M. | Mays, Travis P. | Washburn, Shannon E.
OBJECTIVE To compare analgesic efficacy and fetal effects between transdermal administration of fentanyl and IM administration of buprenorphine in pregnant sheep. ANIMALS 12 healthy pregnant ewes. PROCEDURES Before study initiation, each ewe was confirmed pregnant with a single fetus between 113 and 117 days of gestation. Ewes were randomly assigned to receive buprenorphine (0.01 mg/kg, IM, q 8 h for 48 hours beginning 1 hour before anesthesia induction; n = 6) or fentanyl (a combination of transdermal fentanyl patches sufficient to deliver a dose of 2 μg of fentanyl/kg/h applied between the dorsal borders of the scapulae 24 hours before anesthesia induction; 6). Ewes were anesthetized and underwent a surgical procedure to instrument the fetus with an arterial catheter and place a catheter in utero for collection of amniotic fluid samples. Physiologic variables and behavioral changes indicative of pain were assessed, and amniotic fluid and blood samples from ewes and fetuses were collected for determination of drug concentrations at predetermined times. RESULTS Both protocols provided acceptable postoperative analgesia with no adverse effects observed in the ewes or fetuses. Compared with the buprenorphine protocol, the fentanyl protocol induced more profound analgesia, decreased the requirement for isoflurane during surgery, and was associated with a shorter anesthesia recovery time. Fetal indices did not differ significantly between the 2 analgesic protocols. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that both protocols provided acceptable analgesia. However, the fentanyl protocol was superior in regard to the extent of analgesia induced, inhalant-sparing effects, and anesthesia recovery time.
显示更多 [+] 显示较少 [-]Evaluation of a ventral and a left lateral approach to coelioscopy in bearded dragons (Pogona vitticeps)
2020
Frei, Samuel | Sanchez-Migallon Guzman, David | Kass, Philip H. | Giuffrida, Michelle A. | Mayhew, Philipp D.
OBJECTIVE To compare a ventral and a left lateral endoscopic approach to coelioscopy in bearded dragons (Pogona vitticeps). ANIMALS 18 adult bearded dragons. PROCEDURES In a randomized crossover design involving 2 surgical approaches, anesthetized bearded dragons first underwent coelioscopy with a ventral approach (left lateral of midline next to the umbilicus; animal positioned in dorsal recumbency) or left lateral approach (intercostal; animal positioned in right lateral recumbency) and then with the alternate approach. A 2.7-mm × 18-cm, 30° oblique telescope with a 4.8-mm operating sheath and CO2 insufflation at 2 to 5 mm Hg were used. Ease of entry into the coelom and ease of visual examination of visceral structures were scored. RESULTS Both approaches were straightforward, with the left lateral approach requiring significantly more time than the ventral approach. Scores for ease of visual examination for the heart, lungs, liver, stomach, intestines, pancreas, gallbladder, left kidney, gonads, and fat body were good to excellent. Visual examination of the spleen and adrenal glands was difficult in most animals via either approach. The left kidney, testis, and vas deferens were easier to see with the left lateral approach, whereas the pancreas in females and gallbladder in both sexes were easier to see with the ventral approach. All bearded dragons recovered without complications from the procedures, except for one with nephritis, renal gout, and hepatic necrosis. CONCLUSIONS AND CLINICAL RELEVANCE Both coelioscopy approaches could be safely and effectively used in bearded dragons. Choice of approach should be based on the coelomic structures requiring evaluation.
显示更多 [+] 显示较少 [-]Validating a non-invasive technique for monitoring physiological stress in the samango monkey
2020
Scheun, Juan(South African National Biodiversity Institute National Zoological Garden ,University of Pretoria Faculty of Natural and Agricultural Science Mammal Research Institute) | Tordiffe, Adrian S.W.(University of Pretoria Faculty of Veterinary Science Department of Paraclinical Sciences) | Wimberger, Kirsten(The Wild Bird Trust) | Ganswindt, Andre(South African National Biodiversity Institute National Zoological Garden ,University of Pretoria Faculty of Natural and Agricultural Science Mammal Research Institute)
The non-invasive monitoring of physiological stress can provide conservation and wildlife managers with an invaluable tool for assessing animal welfare and psychological health of captive and free-ranging populations. A significant decrease in free-ranging primate populations globally and an increase in captive-housed primates have led to a need to monitor the stress and general welfare of these animals. We examined the suitability of three enzyme immunoassays (EIAs) for monitoring stress-related physiological responses in the samango monkey, Cercopithecus albogularis erythrarchus. We conducted an adrenocorticotropic hormone (ACTH) challenge on a male and female at the National Zoological Garden, Pretoria, South Africa. Individual faecal samples were collected 8 days pre- and post-ACTH administration and subsequently analysed for faecal glucocorticoid metabolite (fGCM) concentrations. During the study, biological stressors occurred for both the male and female. Two of the three EIAs tested (11-oxoetiocholanolone I and II) were able to reliably monitor fGCM alterations throughout the study period in both sexes. The 11-oxoetiocholanolone I EIA, however, had the lowest mean deviation from the calculated baseline value and was thus chosen as the preferred assay. Both the physiological activation of the stress response and the biological response to a stressor could be monitored with the chosen assay. The successful establishment of a reliable, non-invasive method for monitoring adrenocortical activity in C. albogularis erythrarchus will now allow conservationists, scientific researchers and wildlife managers to evaluate the level of stress experienced, and general welfare, by animals in captivity as well as free-ranging populations.
显示更多 [+] 显示较少 [-]In vitro propagation and genome sequencing of three 'atypical' Ehrlichia ruminantium isolates
2020
Liebenberg, Junita(ARC-Onderstepoort Veterinary Research) | Steyn, Helena C.(ARC-Onderstepoort Veterinary Research) | Josemans, Antoinette I.(ARC-Onderstepoort Veterinary Research) | Faber, Erika(ARC-Onderstepoort Veterinary Research) | Zweygarth, Erich(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases)
Three isolates of Ehrlichia ruminantium (Kümm 2, Omatjenne and Riverside), the causative agent of heartwater in domestic ruminants, were isolated in Ixodes scapularis (IDE8) tick cell cultures using the leukocyte fraction of infected sheep blood. All stocks were successfully propagated in IDE8 cells, whereas initiation attempts using endothelial cell cultures were unsuccessful. Therefore, the new technique should be included in any attempt to isolate field strains of E. ruminantium to enhance the probability of getting E. ruminantium isolates which might not be initiated in endothelial cells. Draft genome sequences of all three isolates were generated and compared with published genomes. The data confirmed previous phylogenetic studies that these three isolates are genetically very close to each other, but distinct from previously characterised E. ruminantium isolates. Genome comparisons indicated that the gene content and genomic synteny were highly conserved, with the exception of the membrane protein families. These findings expand our understanding of the genetic diversity of E. ruminantium and confirm the distinct phenotypic and genetic characteristics shared by these three isolates.
显示更多 [+] 显示较少 [-]Genetic diversity of Ehrlichia ruminantium field strains from selected farms in South Africa
2020
Steyn, Helena C.(Onderstepoort Veterinary Research Vaccine Development and Diagnostics) | Pretorius, Alri(Onderstepoort Veterinary Research Vaccine Development and Diagnostics)
Heartwater is a tick-borne disease caused by the intracellular rickettsial parasite Ehrlichia ruminantium and transmitted by Amblyomma hebraeum ticks. Heartwater is problematic in endemic areas because it causes high mortality in ruminants and leads to economic losses that threaten productivity and food security. This may indicate that there is augmented genetic diversity in the field, which may result in isolates that are more virulent than the Ball3 and Welgevonden isolates. The genetic diversity of E. ruminantium was investigated in this study, focussing on the pCS20 gene region and four polymorphic open reading frames (ORFs) identified by subtractive hybridisation. The 16S ribosomal ribonucleic acid gene confirmed E. ruminantium in brain, blood and tick genomic deoxyribonucleic acid samples (n = 3792) collected from 122 farms that were randomly selected from seven provinces of South Africa where heartwater is endemic. The conserved E. ruminantium pCS20 quantitative polymerase chain reaction (qPCR) assay was used to scan all collected field samples. A total of 433 samples tested positive with the qPCR using the pCS20 gene region, of which 167 were sequenced. The known stocks and field samples were analysed, and phylogenetic trees were generated from consensus sequences. A total of 25 new clades were identified; of these, nine isolates from infected blood could be propagated in cell cultures. These clades were not geographically confined to a certain area but were distributed amongst heartwater-endemic areas in South Africa. Thus, the knowledge of strain diversity of E. ruminantium is essential for control of heartwater and provides a basis for further vaccine development.
显示更多 [+] 显示较少 [-]Study on the prevalence and genetic diversity of Eimeria species from broilers and free-range chickens in KwaZulu-Natal province, South Africa
2020
Fatoba, Abiodun J.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Zishiri, Oliver T.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Blake, Damer P.(The Royal Veterinary College Department of Pathobiology and Population Sciences) | Peters, Sunday O.(Berry College Department of Animal Science) | Lebepe, Jeffrey(University of KwaZulu-Natal School of Life Sciences, College of Agriculture, Engineering and Sciences Department of Biodiversity and Evolutionary Biology) | Mukaratirwa, Samson(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences) | Adeleke, Matthew A.(University of KwaZulu-Natal College of Agriculture, Engineering and Sciences School of Life Sciences)
This study was conducted from January to October 2018 with the objective to determine the prevalence and genetic diversity of Eimeria species in broiler and free-range chickens in KwaZulu-Natal province, South Africa. A total of 342 faecal samples were collected from 12 randomly selected healthy broiler chicken farms and 40 free-range chickens from 10 different locations. Faecal samples were screened for the presence of Eimeria oocysts using a standard flotation method. The species of Eimeria isolates were confirmed by amplification of the internal transcribed spacer 1 (ITS-1) partial region and sequences analysis. Among broiler and free-ranging chickens, 19 out of 41 pens (46.3%) and 25 out of 42 faecal samples (59.5%) were positive for Eimeria infection. Molecular detection revealed the following species: Eimeria maxima, Eimeria tenella, Eimeria acervulina, Eimeria brunetti and Eimeria mitis in all the samples screened. Similarly, polymerase chain reaction assays specific for three cryptic Eimeria operational taxonomic units were negative for all the samples. Phylogenetic analysis of the ITS-1 sequences supported species identity with the greatest variation detected for E. mitis. This study provides information on the range and identity of Eimeria species, and their genetic relatedness, circulating in commercially reared broilers and free-ranging chickens from different locations in KwaZulu-Natal province.
显示更多 [+] 显示较少 [-]Protective efficacy of inactivated Newcastle disease virus vaccines prepared in two different oil-based adjuvants
2020
Aljumaili, Oday A.(Universiti Putra Malaysia Faculty of Veterinary Medicine Department of Veterinary Clinical Studies,Universiti Putra Malaysia Institute of Bioscience Laboratory of Vaccines and Immunotherapeutics) | Bello, Muhammad B.(Universiti Putra Malaysia Institute of Bioscience Laboratory of Vaccines and Immunotherapeutics,Usmanu Danfodiyo University Faculty of Veterinary Medicine Department of Veterinary Microbiology) | Yeap, Swee K.(Universiti Putra Malaysia Institute of Bioscience Laboratory of Vaccines and Immunotherapeutics) | Omar, Abdul R.(Universiti Putra Malaysia Institute of Bioscience Laboratory of Vaccines and Immunotherapeutics,Universiti Putra Malaysia Faculty of Veterinary Medicine Department of Pathology and Microbiology) | Ideris, Aini(Universiti Putra Malaysia Faculty of Veterinary Medicine Department of Veterinary Clinical Studies,Universiti Putra Malaysia Institute of Bioscience Laboratory of Vaccines and Immunotherapeutics)
Despite the availability of Newcastle disease (ND) vaccines for more than six decades, disease outbreaks continue to occur with huge economic consequences to the global poultry industry. The aim of this study is to develop a safe and effective inactivated vaccine based on a recently isolated Newcastle disease virus (NDV) strain IBS025/13 and evaluate its protective efficacy in chicken following challenge with a highly virulent genotype VII isolate. Firstly, high titre of IBS025/13 was exposed to various concentrations of binary ethylenimine (BEI) to determine the optimal conditions for complete inactivation of the virus. The inactivated virus was then prepared in form of a stable water-in-oil emulsion of black seed oil (BSO) or Freund's incomplete adjuvant (FIA) and used as vaccines in specific pathogen-free chicken. Efficacy of various vaccine preparations was also evaluated based on the ability of the vaccine to protect against clinical disease, mortality and virus shedding following challenge with highly virulent genotype\VII NDV isolate. The results indicate that exposure of NDV IBS025/13 to 10 mM of BEI for 21 h at 37 °C could completely inactivate the virus without tempering with the structural integrity of the viral hemagglutin-neuraminidase protein. More so, the inactivated vaccines adjuvanted with either BSO- or FIA-induced high hemagglutination inhibition antibody titre that protected the vaccinated birds against clinical disease and in some cases virus shedding, especially when used together with live attenuated vaccines. Thus, genotype VII-based NDV-inactivated vaccines formulated in BSO could substantially improve poultry disease control particularly when combined with live attenuated vaccines.
显示更多 [+] 显示较少 [-]Effects of refrigerated storage on hemostatic stability of four canine plasma products
2020
Edward, Thomas H. | Meledeo, Michael A. | Peltier, Grantham C. | Ruiz, Daikor D. | Henderson, Alice F. | Travieso, Stephanie | Pusateri, Anthony E.
OBJECTIVE To assess clotting times, coagulation factor activities, sterility, and thromboelastographic parameters of liquid plasma (LP), thawed fresh frozen plasma (FFP-T), and 2 novel formulations of freeze-dried plasma (FDP) stored refrigerated over 35 days. SAMPLE 6 units of canine LP and FFP-T from a commercial animal blood bank and 5 units each of 2 formulations of canine FDP. PROCEDURES Prothrombin time; activated partial thromboplastin time; activities of coagulation factors II, V, VII, VIII, IX, X, XI, and XII; and thromboelastographic parameters were determined for each product on days 0 (baseline), 3, 7, 14, 21, 28, and 35. For each day, a sample of each product was also submitted for aerobic bacterial culture. RESULTS Small changes in coagulation factor activities and mild increased time to initial clot formation in LP and FFP-T were noted over the 35-day storage period. Activities of factor VIII in FDP1 and factor XII in FDP2 were < 50% at baseline but varied throughout. Compared with FFP-T, time to initial clot formation was increased and clot strength was preserved or increased for the FDPs throughout the study. One FDP had decreased pH, compared with other products. No plasma product yielded bacterial growth. CONCLUSIONS AND CLINICAL RELEVANCE Liquid plasma and FFP-T would be reasonable to use when stored refrigerated for up to 35 days. Both FDP products showed variability in coagulation factor activities. Studies investigating the usefulness of these plasma products (FDPs) in dogs and the variable days of refrigerated storage (all products) are warranted.
显示更多 [+] 显示较少 [-]