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Novel use of an activity monitor to model jumping behaviors in cats Texto completo
2020
Sharon, Kate P. | Thompson, Caryn M. | Lascelles, B. Duncan X. | Parrish, Rudolph S.
OBJECTIVE To develop methods to identify and characterize activity monitor (AM) data signatures for jumps performed by cats. ANIMALS 13 healthy, client-owned cats without evidence of osteoarthritis or degenerative joint disease. PROCEDURES Each cat was fitted with the same AM, individually placed in an observation room, then simultaneously recorded by 3 video cameras during the observation period (5 to 8 hours). Each cat was encouraged to jump up (JU), jump down (JD), and jump across (JA) during the observation period. Output from the AM was manually annotated for jumping events, each of which was characterized by functional data analysis yielding relevant coefficients. The coefficients were then used in linear discriminant analysis to differentiate recorded jumps as JUs, JDs, or JAs. To assess the model's ability to distinguish among the 3 jump types, a leave-one-out cross-validation method was used, and the misclassification error rate of the overall categorization of the model was calculated. RESULTS Of 731 jumping events, 29 were misclassified. Overall, the mean misclassification error rate per cat was 5.4% (range, 0% to 12.5%), conversely indicating a correct classification rate per cat of 94.6%. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that the model was successful in correctly identifying JUs, JDs, and JAs in healthy cats. With advancements in AM technology and data processing, there is potential for the model to be applied in clinical settings as a means to obtain objective outcome measures.
Mostrar más [+] Menos [-]Serum paraoxonase-1 activity in tail and mammary veins of ketotic dairy cows Texto completo
2020
Fukumori, R. | Elsayed, H. K. | Oba, M. | Tachibana, Y. | Nakada, K. | Oikawa, S.
The objective of this study was to evaluate the association between ketonemia and serum paraoxonase-1 (PON1), malondialdehyde (MDA), and other blood components in tail and mammary veins of dairy cows. Forty-two Holstein dairy cows with decreased feed intake were divided into HIGH (≥ 1.2 mM; n = 31) and LOW (< 1.2 mM; n = 11) groups based on the β-hydroxybutyrate concentration in plasma collected from the tail vein. The HIGH group had a significantly greater plasma non-esterified fatty acid (NEFA) concentration, but significantly lower serum PON1 activity and phospholipid concentration, and a tendency to have a lower cholesterol ester concentration than the LOW group. Serum PON1 activity was not correlated with the MDA concentration but was positively correlated with serum concentrations of cholesterol esters and phospholipids, and negatively correlated with the plasma NEFA concentration. These results suggest that serum PON1 activity is reduced by hyperketonemia and the relevance of PON1 to MDA seems to not be direct, though it is involved.
Mostrar más [+] Menos [-]Evaluation of jejunal microvasculature of healthy anesthetized dogs with sidestream dark field video microscopy Texto completo
2020
OBJECTIVE To determine the feasibility of sidestream dark field (SDF) video microscopy for the evaluation of the jejunal microvasculature of healthy dogs. ANIMALS 30 healthy sexually intact female shelter dogs anesthetized for ovariohysterectomy. PROCEDURES Preoperative physical and clinicopathologic assessments were performed to confirm health status. Then healthy dogs were anesthetized, and the abdomen was incised at the ventral midline for ovariohysterectomy and jejunal microvasculature evaluation. An SDF video microscope imaged the microvasculature of 2 sites of a portion of the jejunum, and recorded videos were analyzed with software capable of quantitating parameters of microvascular health. Macrovascular parameters (heart rate, respiratory rate, and hemoglobin oxygen saturation) were also recorded during anesthesia. RESULTS Quantified jejunal microvascular parameters included valid microvascular density (mean ± SD, 251.72 ± 97.10 μm/mm), RBC-filling percentage (66.96 ± 8.00%), RBC column width (7.11 ± 0.72 μm), and perfused boundary region (2.17 ± 0.42 μm). The perfused boundary region and RBC-filling percentage had a significant negative correlation. Strong to weak positive correlations were noted among the perfused boundary regions of small-, medium-, and large-sized microvessels. No significant correlations were identified between microvascular parameters and age, body weight, preoperative clinicopathologic results, or macrovascular parameters. CONCLUSIONS AND CLINICAL RELEVANCE Interrogation of the jejunal microvasculature of healthy dogs with SDF video microscopy was feasible. Results of this study indicated that SDF video microscopy is worth additional investigation, including interrogation of diseased small intestine in dogs.
Mostrar más [+] Menos [-]Pathogenesis, detection, and control of scrapie in sheep Texto completo
2020
Cassmann, Eric D. | Greenlee, Justin J.
In sheep, scrapie is a fatal neurologic disease that is caused by a misfolded protein called a prion (designated PrPSc). The normal cellular prion protein (PrPC) is encoded by an endogenous gene, PRNP, that is present in high concentrations within the CNS. Although a broad range of functions has been described for PrPC, its entire range of functions has yet to be fully elucidated. Accumulation of PrPSc results in neurodegeneration. The PRNP gene has several naturally occurring polymorphisms, and there is a strong correlation between scrapie susceptibility and PRNP genotype. The cornerstone of scrapie eradication programs is the selection of scrapie-resistant genotypes to eliminate classical scrapie. Transmission of classical scrapie in sheep occurs during the prenatal and periparturient periods when lambs are highly susceptible. Initially, the scrapie agent is disseminated throughout the lymphoid system and into the CNS. Shedding of the scrapie agent occurs before the onset of clinical signs. In contrast to classical scrapie, atypical scrapie is believed to be a spontaneous disease that occurs in isolated instances in older animals within a flock. The agent that causes atypical scrapie is not considered to be naturally transmissible. Transmission of the scrapie agent to species other than sheep, including deer, has been experimentally demonstrated as has the transmission of nonscrapie prion agents to sheep. The purpose of this review is to outline the current methods for diagnosing scrapie in sheep and the techniques used for studying the pathogenesis and host range of the scrapie agent. Also discussed is the US scrapie eradication program including recent updates.
Mostrar más [+] Menos [-]Biochemical, functional, and histopathologic characterization of lomustine-induced liver injury in dogs Texto completo
2020
Dedeaux, Andrea M. | Flesner, Brian K. | Reinhart, Jennifer M. | Langohr, Ingeborg M. | Husnik, Roman | Geraci, Shawn N. | Toboada, Joseph | Rademacher, Nathalie | Thombs, Lori A. | Bryan, Jeffrey N. | Trepanier, Lauren A. | Boudreaux, Bonnie B.
OBJECTIVE To characterize the biochemical, functional, and histopathologic changes associated with lomustine-induced liver injury in dogs. ANIMALS I0 healthy purpose-bred sexually intact female hounds. PROCEDURES Dogs were randomly assigned to receive lomustine (approx 75 mg/m2, PO, q 21 d for 5 doses) alone (n = 5) or with prednisone (approx 1.5 mg/kg, PO, q 24 h for 12 weeks; 5). For each dog, a CBC, serum biochemical analysis, liver function testing, urinalysis, and ultrasonographic examination of the liver with acquisition of liver biopsy specimens were performed before and at predetermined times during and after lomustine administration. Results were compared between dogs that did and did not receive prednisone. RESULTS 7 of the I0 dogs developed clinical signs of liver failure. For all dogs, serum alanine aminotransferase (ALT) and alkaline phosphatase (ALP) activities, bile acid concentrations, and liver histologic score increased and hepatic reduced glutathione content decreased over time. Peak serum ALT (r = 0.79) and ALP (r = 0.90) activities and bile acid concentration (r = 0.68) were positively correlated with the final histologic score. Prednisone did not appear to have a protective effect on histologic score. CONCLUSIONS AND CLINICAL RELEVANCE In dogs, liver enzyme activities, particularly ALT and ALP activities, should be closely monitored during lomustine treatment and acute increases in those activities may warrant discontinuation of lomustine to mitigate liver injury. Nonspecific ultrasonographic findings and abnormal increases in liver function tests were not detected until the onset of clinical liver failure. Glutathione depletion may have a role in lomustine-induced hepatopathy and warrants further investigation.
Mostrar más [+] Menos [-]Experimental evaluation of tulathromycin as a treatment for Campylobacter jejuni abortion in pregnant ewes Texto completo
2020
Yeager, Michael J. | Wu, Zuowei | Plummer, Paul J. | Sahin, Orhan | Ocal, Melda Meral | Beyi, Ashenafi F. | Changyun, Xu | Zhang, Qijing | Griffith, Ronald W.
OBJECTIVE To evaluate the efficacy of tulathromycin for prevention of abortion in pregnant ewes when administered within 24 hours after experimental inoculation with Campylobacter jejuni. ANIMALS 20 pregnant ewes between 72 and 92 days of gestation. PROCEDURES All ewes were inoculated with a field strain of C jejuni (8.5 × 108 to 10.6 × 108 CFUs, IV). Eighteen hours later, ewes received either tulathromycin (1.1 mL/45 kg [2.4 mg/kg], SC; n = 10) or sterile saline (0.9% NaCl) solution (1.1 mL/45 kg, SC; sham; 10). Ewes were euthanized immediately after observation of vaginal bleeding, abortion, or completion of a 21-day observation period. Necropsy was performed on all ewes, and tissue specimens were obtained for bacterial culture and histologic examination. RESULTS 1 sham-treated ewe and 1 tulathromycin-treated ewe developed signs of severe endotoxemia and were euthanized within 24 hours after C jejuni inoculation. Seven sham-treated and 2 tulathromycin-treated ewes developed vaginal bleeding or aborted and were euthanized between 4 and 21 days after C jejuni inoculation. The proportion of tulathromycin-treated ewes that developed vaginal bleeding or aborted during the 21 days after C jejuni inoculation (2/9) was significantly less than that for the sham-treated ewes (7/9). CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that administration of tulathromycin to pregnant ewes following exposure to C jejuni was effective in decreasing the number of C jejuni–induced abortions. Because of concerns regarding the development of macrolide resistance among Campylobacter strains, prophylactic use of tulathromycin in sheep is not recommended.
Mostrar más [+] Menos [-]Acknowledgement to reviewers Texto completo
2020
Editorial Office
No abstract available.
Mostrar más [+] Menos [-]Histological and Histochemical investigation of the development of the New -Zealand rabbit’s gastric glands Texto completo
2020
Shehata M.M.Soliman1 | Abdel-Razik H. Abdel-Razik2 | Marwa M. Hussein3 | Omima M. M. Rashad1
The present study aimed to provide a detailed description of the normal development of rabbit stomach and focusing on the histogenesis of gastric glands. In a total, 24 New Zealand White rabbit fetuses were collected at gestational days 21, 25, and 29. The stomachs of the collected fetuses were fixed in 10% neutral buffered formalin and prepared by paraffin technique then stained with Harris's Haematoxylin and Eosin, Masson's Trichrome stain, Orcein, Periodic acid-Schiff, Alcian blue, and Bromophenol blue stains. The results revealed that, at 21stgestational day, the different parts of the stomach including, cardia, fundus and pylorus could be easily distinguished. On 25th developmental day, the gastric mucosal folds were more prominent in the cardia than fundus and pylorus. At 29th developmental day, tunica mucosa and tunica submucosa of the fetal stomach were laid in longitudinally oriented folds known as rugae. The gastric gland in this age became well developed containing well-demarcated oxyntic and peptic cells. In conclusion, the rabbit stomach is completely differentiated during the embryonic life and the gastric glands were functionally active.
Mostrar más [+] Menos [-]Antibiotic resistance profile of Gram-negative bacteria isolated from Lafenwa abattoir effluent and its receiving water (Ogun River) in Abeokuta, Ogun state, Nigeria Texto completo
2020
Samuel N. Akpan | Olubusola A. Odeniyi | Oluwawemimo O. Adebowale | Selim A. Alarape | Olanike K. Adeyemo
Antibiotic resistance profile of Gram-negative bacteria isolated from Lafenwa abattoir effluent and its receiving water (Ogun River) in Abeokuta, Ogun state, Nigeria Texto completo
2020
Samuel N. Akpan | Olubusola A. Odeniyi | Oluwawemimo O. Adebowale | Selim A. Alarape | Olanike K. Adeyemo
Untreated abattoir effluent constitutes potential reservoir for transmission of pathogenic strains of multiple antibiotic-resistant bacteria by pollution of surface and ground water sources. This study was carried out to determine the antibiotic resistance and extended spectrum β-lactamase (ESBL) production profiles of Gram-negative bacteria isolated from effluent collected from Lafenwa municipal abattoir and its receiving surface water, Ogun River, in Abeokuta, Ogun state, Nigeria. Twelve effluent and 18 water samples were collected for this study. Total heterotrophic and coliform counts were estimated, bacterial identification was performed using standard culture-based procedures, whilst antibiotic resistance profiles of isolated bacteria against five antibiotics (ceftazidime, cefpodoxime, cefotaxime, ertapenem and amoxicillin-clavulanate) and detection of ESBLs were done using disk diffusion and double-disc synergy tests. A total of 54 Gram-negative bacteria were isolated, including Salmonella spp. (9), Escherichia coli (15), Klebsiella spp. (7), Shigella spp. (5), Pseudomonas spp. (12) and Enterobacter spp. (6). Both Enterobacteriaceae and Pseudomonas isolates (31% and 66.6%, respectively) were resistant to all selected antibiotics except ertapenem (98% susceptibility). Overall, 77% isolates had multiple antibiotic resistance index (MARI) values, but none of the antibiotic-resistant isolates showed evidence of ESBL production. The presence of multiple antibiotic-resistant isolates in the effluent and receiving water of Lafenwa abattoir suggests a major risk to public health and food safety. Current methods of waste disposal at the abattoir are unacceptable and greatly reduce the qualities of the processed meat and contaminate the environment. There is a need for improved abattoir waste management and water treatment strategies.
Mostrar más [+] Menos [-]Antibiotic resistance profile of Gram-negative bacteria isolated from Lafenwa abattoir effluent and its receiving water (Ogun River) in Abeokuta, Ogun state, Nigeria Texto completo
2020
Akpan, Samuel N.(University of Ibadan Faculty of Veterinary Medicine Department of Veterinary Public Health and Preventive Medicine) | Odeniyi, Olubusola A.(University of Ibadan Faculty of Sciences Department of Microbiology) | Adebowale, Oluwawemimo O.(Federal University of Agriculture College of Veterinary Medicine Department of Veterinary Public Health and Preventative Medicine) | Alarape, Selim A.(University of Ibadan Faculty of Veterinary Medicine Department of Veterinary Public Health and Preventive Medicine) | Adeyemo, Olanike K.(University of Ibadan Faculty of Veterinary Medicine Department of Veterinary Public Health and Preventive Medicine)
Untreated abattoir effluent constitutes potential reservoir for transmission of pathogenic strains of multiple antibiotic-resistant bacteria by pollution of surface and ground water sources. This study was carried out to determine the antibiotic resistance and extended spectrum β-lactamase (ESBL) production profiles of Gram-negative bacteria isolated from effluent collected from Lafenwa municipal abattoir and its receiving surface water, Ogun River, in Abeokuta, Ogun state, Nigeria. Twelve effluent and 18 water samples were collected for this study. Total heterotrophic and coliform counts were estimated, bacterial identification was performed using standard culture-based procedures, whilst antibiotic resistance profiles of isolated bacteria against five antibiotics (ceftazidime, cefpodoxime, cefotaxime, ertapenem and amoxicillin-clavulanate) and detection of ESBLs were done using disk diffusion and double-disc synergy tests. A total of 54 Gram-negative bacteria were isolated, including Salmonella spp. (9), Escherichia coli (15), Klebsiella spp. (7), Shigella spp. (5), Pseudomonas spp. (12) and Enterobacter spp. (6). Both Enterobacteriaceae and Pseudomonas isolates (31% and 66.6%, respectively) were resistant to all selected antibiotics except ertapenem (98% susceptibility). Overall, 77% isolates had multiple antibiotic resistance index (MARI) values, but none of the antibiotic-resistant isolates showed evidence of ESBL production. The presence of multiple antibiotic-resistant isolates in the effluent and receiving water of Lafenwa abattoir suggests a major risk to public health and food safety. Current methods of waste disposal at the abattoir are unacceptable and greatly reduce the qualities of the processed meat and contaminate the environment. There is a need for improved abattoir waste management and water treatment strategies.
Mostrar más [+] Menos [-]Failure of diplodiatoxin to induce diplodiosis in juvenile goats Texto completo
2020
Christo J. Botha | Louis G.J. Ackerman | Mxolisi G. Masango | Luke F. Arnot
Failure of diplodiatoxin to induce diplodiosis in juvenile goats Texto completo
2020
Christo J. Botha | Louis G.J. Ackerman | Mxolisi G. Masango | Luke F. Arnot
Diplodiosis is an important neuromycotoxicosis of ruminants in South Africa when grazing on harvested maize fields in winter. It is believed to be caused by mycotoxin(s) synthesised by Stenocarpella (Diplodia) maydis. Although several metabolites have been isolated from S. maydis culture material, none of these have been administered to ruminants to reproduce the disease. The objectives of this study were to isolate diplodiatoxin and to administer it to juvenile goats. Diplodiatoxin, considered as a major metabolite, was purified from S. maydis-infected maize cultures (Coligny 2007 isolate). Following intravenous administration of 2 mg and 4 mg diplodiatoxin/kg body weight for five consecutive days to two juvenile goats, no clinical signs reminiscent of diplodiosis were observed. Based on previous experimental results and if diplodiatoxin was the causative compound, the dosage regimen employed was seemingly appropriate to induce diplodiosis. In addition, intraruminal administration of 2 mg/kg diplodiatoxin to one goat for three consecutive days also did not induce clinical signs. It appears as if diplodiatoxin alone is not the causative compound. Other metabolites and/or mixtures of diplodiatoxin and other mycotoxins, when available in sufficient quantities, should also be evaluated.
Mostrar más [+] Menos [-]Failure of diplodiatoxin to induce diplodiosis in juvenile goats Texto completo
2020
Botha, Christo J.(University of Pretoria Faculty of Veterinary Science Department of Paraclinical Sciences) | Ackerman, Louis G.J.(University of Pretoria Faculty of Veterinary Science Department of Paraclinical Sciences) | Masango, Mxolisi G.(University of the Witwatersrand Analytics and Institutional Research Unit) | Arnot, Luke F.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies)
Diplodiosis is an important neuromycotoxicosis of ruminants in South Africa when grazing on harvested maize fields in winter. It is believed to be caused by mycotoxin(s) synthesised by Stenocarpella (Diplodia) maydis. Although several metabolites have been isolated from S. maydis culture material, none of these have been administered to ruminants to reproduce the disease. The objectives of this study were to isolate diplodiatoxin and to administer it to juvenile goats. Diplodiatoxin, considered as a major metabolite, was purified from S. maydis-infected maize cultures (Coligny 2007 isolate). Following intravenous administration of 2 mg and 4 mg diplodiatoxin/kg body weight for five consecutive days to two juvenile goats, no clinical signs reminiscent of diplodiosis were observed. Based on previous experimental results and if diplodiatoxin was the causative compound, the dosage regimen employed was seemingly appropriate to induce diplodiosis. In addition, intraruminal administration of 2 mg/kg diplodiatoxin to one goat for three consecutive days also did not induce clinical signs. It appears as if diplodiatoxin alone is not the causative compound. Other metabolites and/or mixtures of diplodiatoxin and other mycotoxins, when available in sufficient quantities, should also be evaluated.
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