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Localization of the cutaneus trunci muscle reflex in horses
2013
Essig, Cynthia M. | Merritt, Jonathan S. | Stubbs, Narelle C. | Clayton, Hilary M.
Objective—To determine the magnitude and location of skin movement attributable to the cutaneus trunci muscle reflex in response to localized stimulation of the skin of the dorsolateral aspect of the thoracic wall in horses. Animals—8 horses. Procedures—A grid of 56 reflective markers was applied to the lateral aspect of the body wall of each horse; markers were placed at 10-cm intervals in 7 rows and 8 columns. A motion analysis system with 10 infrared cameras was used to track movements of the markers in response to tactile stimulation of the dorsolateral aspect of the thoracic wall at the levels of T6, T11, and T16. Marker movement data determined after skin stimulation were used to create a skin deformation gradient tensor field, which was analyzed with custom software. Results—The sites of maximal skin deformation were located close to the stimulation sites; the centers of the twitch responses were located a mean distance of 7.7 to 12.8 cm ventral and between 6.6 cm cranial and 3.1 cm caudal to the stimulation sites. Conclusions and Clinical Relevance—Findings of this study may have implications for assessment of nerve conduction velocities of the cutaneus trunci muscle reflex and may enhance understanding of the responses of horses to placement of tack or other equipment on skin over the cutaneus trunci muscles.
Mostrar más [+] Menos [-]Kinematic and kinetic analysis of dogs during trotting after amputation of a thoracic limb
2013
Jarvis, Sarah L. | Worley, Deanna R. | Hogy, Sara M. | Hill, Ashley E. | Haussler, Kevin K. | Reiser, Raoul F II
Objective-To characterize biomechanical differences in gait between dogs with and without an amputated thoracic limb. Animals-Client-owned dogs (16 thoracic-limb amputee and 24 quadruped [control] dogs). Procedures-Dogs were trotted across 3 in-series force platforms. Spatial kinematic and kinetic data were recorded for each limb during the stance phase. Results-Amputees had significant increases in stance duration and vertical impulse in all limbs, compared with values for control dogs. Weight distribution was significantly increased by 14% on the remaining thoracic limb and by a combined 17% on pelvic limbs in amputees. Braking ground reaction force (GRF) was significantly increased in the remaining thoracic limb and pelvic limb ipsilateral to the amputated limb. The ipsilateral pelvic limb had a significantly increased propulsive GRF. The carpus and ipsilateral hip and stifle joints had significantly greater flexion during the stance phase. The cervicothoracic vertebral region had a significantly increased overall range of motion (ROM) in both the sagittal and horizontal planes. The thoracolumbar vertebral region ROM increased significantly in the sagittal plane but decreased in the horizontal plane. The lumbosacral vertebral region had significantly greater flexion without a change in ROM. Conclusions and Clinical Relevance-Compared with results for quadruped dogs, the vertebral column, carpus, and ipsilateral hip and stifle joints had significant biomechanical changes after amputation of a thoracic limb. The ipsilateral pelvic limb assumed dual thoracic and pelvic limb roles because the gait of a thoracic limb amputee during trotting appeared to be a mixture of various gait patterns.
Mostrar más [+] Menos [-]Effects of oxygen insufflation rate, respiratory rate, and tidal volume on fraction of inspired oxygen in cadaveric canine heads attached to a lung model
2013
Zimmerman, Melina E. | Hodgson, David S. | Bello, Nora M.
Objective-To assess the effects of oxygen insufflation rate, respiratory rate, and tidal volume on fraction of inspired oxygen (Fio2) in cadaveric canine heads attached to a lung model. Sample-16 heads of canine cadavers. Procedures-Each cadaver head was instrumented with a nasal insufflation catheter through which oxygen was delivered. The trachea was attached to a sample collection port connected by means of corrugated tubing to a lung model. Eight treatment combinations that varied in respiratory rate (10 or 20 breaths/min), tidal volume (10 or 15 mL/kg), and oxygen insufflation rate (50 or 100 mL/kg/min) were applied to each head in a replicated Latin square design. Gas samples were manually collected, and inspired oxygen concentrations were analyzed. The Fio2 and end-tidal CO2 concentration were determined and compared among sample groups. Results-Estimated least squares mean Fio2 for various treatment combinations ranged from 32.2% to 60.6%. The Fio2 was significantly increased at the higher insufflation rate (estimated marginal least squares mean, 48.7% vs 38.6% for 100 and 50 mL/kg/min, respectively), lower respiratory rate (48.9% vs 38.3% for 10 and 20 breaths/min, respectively), and smaller tidal volume (46.8% vs 40.0% for 10 and 15 mL/kg, respectively). Conclusions and Clinical Relevance-Fio2 in the model was affected by oxygen insufflation rate, respiratory rate, and tidal volume. This information may potentially help clinicians interpret results of blood gas analysis and manage canine patients receiving oxygen insufflation via a nasal catheter.
Mostrar más [+] Menos [-]Effect of transportation during periods of high ambient temperature on physiologic and behavioral indices of beef heifers
2013
Theurer, Miles E. | White, Brad J. | Anderson, David E. | Miesner, Matt D. | Mosier, Derek A. | Coetzee, Johann F. | Amrine, David E.
Objective: To determine the effect of transportation during periods of high ambient temperature on physiologic and behavioral indices of beef heifers. Animals: 20 heifers (mean body weight, 217.8 kg). Procedures: Ten heifers were transported 518 km when the maximum ambient temperature was ≥ 32.2°C while the other 10 heifers served as untransported controls. Blood samples were collected from transported heifers at predetermined intervals during the transportation period. For all heifers, body weights, nasal and rectal temperatures, and behavioral indices were measured at predetermined intervals for 3 days after transportation. A week later, the entire process was repeated such that each group was transported twice and served as the control twice. Results: Transported heifers spent more time near the hay feeder on the day of transportation, had lower nasal and rectal temperatures for 24 hours after transportation, and spent more time lying down for 2 days after transportation, compared with those indices for control heifers. Eight hours after transportation, the weight of transported heifers decreased 6%, whereas that of control heifers increased 0.6%. At 48 hours after initiation of transportation, weight, rectal temperature, and time spent at various pen locations did not differ between transported and control heifers. Cortisol concentrations were higher 4 hours after initiation of transportation, compared with those determined just prior to transportation. Conclusions and Clinical Relevance: Results indicated transportation during periods of high ambient temperatures caused transient changes in physiologic and behavioral indices of beef heifers.
Mostrar más [+] Menos [-]Orthotopic model of canine osteosarcoma in athymic rats for evaluation of stereotactic radiotherapy
2013
Schwartz, Anthony L. | Custis, James T. | Harmon, Joseph F. | Powers, Barbara E. | Chubb, Laura S. | LaRue, Susan M. | Ehrhart, Nicole P. | Ryan, Stewart D.
Objective: To develop an orthotopic model of canine osteosarcoma in athymic rats as a model for evaluating the effects of stereotactic radiotherapy (SRT) on osteosarcoma cells. Animals: 26 athymic nude rats. Procedures: 3 experiments were performed. In the first 2 experiments, rats were injected with 1 × 10(6) Abrams canine osteosarcoma cells into the proximal aspect of the tibia (n = 12) or distal aspect of the femur (6). Tumor engraftment and progression were monitored weekly via radiography, luciferase imaging, and measurement of urine pyridinoline concentration for 5 weeks and histologic evaluation after euthanasia. In the third experiment, 8 rats underwent canine osteosarcoma cell injection into the distal aspect of the femur and SRT was administered to the affected area in three 12-Gy fractions delivered on consecutive days (total radiation dose, 36 Gy). Percentage tumor necrosis and urinary pyridinoline concentrations were used to assess local tumor control. The short-term effect of SRT on skin was also evaluated. Results: Tumors developed in 10 of 12 tibial sites and all 14 femoral sites. Administration of SRT to rats with femoral osteosarcoma was feasible and successful. Mean tumor necrosis of 95% was achieved histologically, and minimal adverse skin effects were observed. Conclusions and Clinical Relevance: The orthotopic model of canine osteosarcoma in rats developed in this study was suitable for evaluating the effects of local tumor control and can be used in future studies to evaluate optimization of SRT duration, dose, and fractionation schemes. The model could also allow evaluation of other treatments in combination with SRT, such as chemotherapy or bisphosphonate, radioprotectant, or parathyroid hormone treatment.
Mostrar más [+] Menos [-]Assessment of calcitonin response to experimentally induced hypercalcemia in cats
2013
Pineda, Carmen | Aguilera-Tejero, Escolastico | Raya, Ana I. | Guerrero, Fatima | Rodríguez, Mariano | López Moreno, Ignacio
Objective—To characterize the dynamics of calcitonin secretion in response to experimentally induced hypercalcemia in cats. Animals—13 healthy adult European Shorthair cats.Procedures—For each cat, the calcitonin response to hypercalcemia (defined as an increase in ionized calcium concentration > 0.3mM) was investigated by infusing calcium chloride solution and measuring circulating calcitonin concentrations before infusion (baseline) and at various ionized calcium concentrations. Calcitonin expression in the thyroid glands of 10 of the cats was investigated by immunohistochemical analysis. Results—Preinfusion baseline plasma calcitonin concentrations were very low in many cats, sometimes less than the limit of detection of the assay. Cats had a heterogeneous calcitonin response to hypercalcemia. Calcitonin concentrations only increased in response to hypercalcemia in 6 of 13 cats; in those cats, the increase in calcitonin concentration was quite variable. In cats that responded to hypercalcemia, calcitonin concentration increased from 1.3 ± 0.3 pg/mL at baseline ionized calcium concentration to a maximum of 21.2 ± 8.4 pg/mL at an ionized calcium concentration of 1.60mM. Cats that did not respond to hypercalcemia had a flat calcitonin-to-ionized calcium concentration curve that was not modified by changes in ionized calcium concentration. A significant strong correlation (r = 0.813) was found between the number of calcitonin-positive cells in the thyroid gland and plasma calcitonin concentrations during hypercalcemia. Conclusions and Clinical Relevance—Healthy cats had very low baseline plasma calcitonin concentrations. A heterogeneous increase in plasma calcitonin concentration in response to hypercalcemia, which correlated with the expression of calcitonin-producing cells in the thyroid, was identified in cats.
Mostrar más [+] Menos [-]Construction of an artificial recombinant bicistronic plasmid DNA vaccine against porcine rotavirus
2013
Cui, Tingting(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Xiong, Jun(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Wang, Yongzhi(Sichuan Rural Science and Technology Development Centre) | Wen, Xintian(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Huang, Xiaobo(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Huang, Yong(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Ma, Xiaoping | Hu, Zhongkai(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Zhao, Qin | Cao, Sanjie(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine)
The attenuated Salmonella typhimurium χ4550 strain was used to harbour a reconstructed bicistronic DNA vaccine against porcine rotavirus, which carried the rotavirus nonstructural protein 4 (NSP4) and VP7 genes simultaneously. Using a balanced lethal system, the kanamycin resistance gene of expressing eukaryotic plasmids pVAX1 and pVAXD were replaced by the aspartate β-semialdehyde dehydrogenase (asd) gene. The NSP4 cleavage product (259-525) of rotavirus OSU strain and VP7 full-length genes were amplified by reverse transcription polymerase chain reaction and then inserted into the eukaryotic single-expression plasmid, pVAX1-asd, and the eukaryotic dual-expression plasmid, pVAXD-asd, respectively. The recombinant plasmids pVAX1-asd-NSP4, pVAX1-asd-VP7 and pVAXD-asd-NSP4-VP7 were transformed into the attenuated S. typhimurium χ4550 strain by electrotransformation. An indirect immunofluorescence assay of the expressed COS-7 cell suggested that the recombinant S. typhimurium χ4550 strain was constructed successfully. The recombinant S. typhimurium χ4550 strain was orally administered to BALB/c mice. The group immunised with dual-expression plasmids produced a significantly higher level of serum Immunoglobulin G (IgG) and intestinal Immunoglobulin A (IgA) than the group immunised with single-expression plasmids. These results indicated that eukaryotic bicistronic plasmid DNA vaccines could be successfully constructed to enhance humoural, mucosal and cellular immune response against rotavirus infection.
Mostrar más [+] Menos [-]Construction and immunogenicity of a ΔapxIC/ompP2 mutant of Actinobacillus pleuropneumonias and Haemophilus parasuis
2013
Liu, Qiong(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Gong, Yuheng(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Cao, Yuqin(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Wen, Xintian(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Huang, Xiaobo(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Yan, Qigui(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Huang, Yong(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine) | Cao, Sanjie(Sichuan Agricultural University Institute of Preventive Veterinary Medicine College of Veterinary Medicine)
The apxIC genes of the Actinobacillus pleuropneumoniae serovar 5 (SC-1), encoding the ApxI-activating proteins, was deleted by a method involving sucrose counter-selection. In this study, a mutant strain of A. pleuropneumoniae (SC-1) was constructed and named AapxIC/ ompP2. The mutant strain contained foreign DNA in the deletion site of ompP2 gene of Haemophilus parasuis. It showed no haemolytic activity and lower virulence of cytotoxicity in mice compared with the parent strain, and its safety and immunogenicity were also evaluated in mice. The LD50 data shown that the mutant strain was attenuated 30-fold, compared with the parent strain (LD50 of the mutant strain and parent strain in mice were determined to be 1.0 x 10(7) CFU and 3.5 x 10(5) CFU respectively). The mutant strain that was attenuated could secrete inactivated ApxIA RTX toxins with complete antigenicity and could be used as a candidate live vaccine strain against infections of A. pleuropneumoniae and H. parasuis.
Mostrar más [+] Menos [-]Prevalence of peste des petits ruminants in the arid zone in the Republic of Niger
2013
Farougou, Souaibou(University of Abomey-Calavi) | Gagara, Mariama(University of Abomey-Calavi) | Mensah, Guy A.(National Institute of Agricultural Research of Benin)
The study aimed to determine the prevalence of peste des petits ruminants in the arid zone (Niamey, Tillabéry and Tahoua) of the Republic of Niger. A serological survey was conducted and 519 serum samples were collected from 253 unvaccinated sheep and 266 unvaccinated goats. The sample included 340 female animals (168 sheep and 172 goats) and 160 kids and lambs (78 lambs and 82 kids). A competitive enzyme-linked immunosorbent assay yielded an overall seroprevalence of 45.0%. The prevalence in sheep was 42.0% compared with 47.9% in goats. The seroprevalence observed amongst small ruminants in Tahoua (49.8%) and Tillabéry (46.6%) was significantly higher (p = 0.001) than that observed in animals from Niamey (25.1%). It was also higher (p = 0.04) in sheep younger than two years (51.8%) than in adults (37.6%). Conversely, the seroprevalence showed no significant difference between male animals (35.8% in sheep; 50.1% in goats) and female animals (45.1% in sheep; 46.4% in goats). The prevalence of the disease observed amongst the sheep and goat populations confirms the continued danger of this disease in the areas studied. It is therefore necessary to develop strategies such as improving livestock services, providing effective vaccines and implementing a vaccination programme for an effective control of the disease in sub-Saharan Africa.
Mostrar más [+] Menos [-]Molecular surveillance of Theileria ovis, Theileria lestoquardi and Theileria annulata infection in sheep and ixodid ticks in Iran
2013
Razmi, Gholamreza(Ferdowsi University of Mashhad) | Yaghfoori, Saeed(Ferdowsi University of Mashhad)
A molecular study was undertaken to detect Theileria ovis, Theileria lestoquardi and Theileria annulata in sheep and tick vectors. Investigation was conducted from 2010 to 2011 in the south of Khorasan Razavi Province, Iran. A total of 150 blood samples were collected from 30 different sheep flocks. In addition, ixodid ticks were sampled from the same flocks. The stained blood smears were microscopically examined for the presence of piroplasms and a semi-nested polymerase chain reaction-restriction (PCR) was used for subsequent molecular speciation. Salivary glands were isolated from the ticks and subsequently analysed by semi-nested PCR. polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to differentiate between T. lestoquardi and T. annulata from PCR-positive samples. Theileria species infection was microscopically detected in 18.6% of blood smears. The presence of T. ovis and T. lestoquardi or T. annulata was detected by semi-nested PCR in 58.6% and 6.6% of blood samples respectively. In total, 169 ixodid ticks were collected from different areas of the province. The most prevalent ticks were Rhipicephalus turanicus (n = 155; 91.7% of the total), followed by Hyalomma anatolicum anatolicum (n = 8; 4.7%) and Hyalomma marginatum turanicum (n = 6; 3.5%). From an organ pooling of 33 ticks, three pools of salivary glands from R. turanicus were positive for Theileria species by semi-nested PCR. Of the three R. turanicus samples testing positive for Theileria species, two (6.1%) were positive for T. ovis and one (3.0%) for T. lestoquardi or T.annulata. Amongst the 11 PCR-positive samples for T. lestoquardi or T. annulata, 10 were positive for T. lestoquardi and one sample was positive for both T. lestoquardi and T. annulata using PCR-RFLP. The results also demonstrated that PCR-RFLP could be used for the detection of T. ovis. Based on the results, it can be concluded that T. ovis has a higher prevalence than T. lestoquardi, and that R. turanicus could be a possible vector for T. ovis and T. lestoquardi. Finally, the PCR-RFLP based on Msp1 restriction enzyme is a simple method for differentiation of Theileria species in sheep and ixodid ticks.
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