This study was undertaken to investigate drug resistance in Escherichia coli (E. coli) strains isolated from bamboo rats in Zhejiang province of China. One hundred and fifty-four E. coli strains were isolated from dead bamboo rats. Polymerase chain reaction (PCR) was used to detect the representative genes encoding resistance to commonly used β-lactam antibiotics. Highest resistance was observed for cefradine (24.03%), followed by penicillin (20.78%) and ceftazidime (20.13%). The isolation rates of β-lactam resistance genes were 53.25, 48.70, 15.58 and 14.29% for bla TEM, bla CTX-M, bla OXA and bla SHV, respectively, while 62 (40.26%) E. coli isolates harbored multiple β-lactam resistance genes. These results also suggested that long term use of these antibiotics leads to antibimicrobial resistance. We believe that this study will provide a guideline for veterinarians and a research basis for examining resistance-encoding genes in other food animals like bamboo rats.
Swine edema disease is caused by Shiga toxin (Stx) 2e–producing Escherichia coli (STEC). Addition of highly concentrated zinc formulations to feed has been used to treat and prevent the disease, but the mechanism of the beneficial effect is unknown. The purpose of the present study was to investigate the effects of highly concentrated zinc formulations on bacterial growth, hemolysin production, and an Stx2e release by STEC in vitro. STEC strain MVH269 isolated from a piglet with edema disease was cultured with zinc oxide (ZnO) or with zinc carbonate (ZnCO3), each at up to 3,000 ppm. There was no effect of zinc addition on bacterial growth. Nonetheless, the cytotoxic activity of Stx2e released into the supernatant was significantly attenuated in the zinc-supplemented media compared to that in the control, with the 50% cytotoxic dose values of 163.2 ± 12.7, 211.6 ± 33.1 and 659.9 ± 84.2 after 24 hr of growth in the presence of ZnO, ZnCO3, or no supplemental zinc, respectively. The hemolytic zones around colonies grown on sheep blood agar supplemented with zinc were significantly smaller than those of colonies grown on control agar. Similarly, hemoglobin absorbance after exposure to the supernatants of STEC cultures incubated in sheep blood broth supplemented with zinc was significantly lower than that resulting from exposure to the control supernatant. These in vitro findings indicated that zinc formulations directly impair the factors associated with the virulence of STEC, suggesting a mechanism by which zinc supplementation prevents swine edema disease.
Day-old chicks from 3 hatcheries were placed on bedding paper and brought to a commercial broiler farm between January and July 2016. Sixty-six samples of the paper, which were stained with meconium droppings of the chicks, were collected and examined for isolation of cephalosporin-resistant Enterobacteriaceae. Cefotaxime (CTX)-resistant Klebsiella pneumoniae (1 isolate) and Enterobacter cloacae (4 isolates) were isolated from 5 (7.58%) of the 66 samples. Conjugation experiments revealed that the blaCTX-M-25 gene conferring CTX resistance was transferred from the K. pneumoniae isolate and 2 of the 4 E. cloacae isolates to Escherichia coli DH5α via IncA/C plasmids carrying the gene. Our results suggested that the blaCTX-M-25 gene originating from chicks may be spread among commercial broiler farms.
To investigate the genetic variation in Haemophilus parasuis (HPS) in Sichuan, China, 11 isolates were analyzed based on the outer membrane protein P2 (OMPP2) sequence. Sequence analysis showed that the 11 isolates shared 93.0 to 100% nucleotide homology with 15 reference strains, and the consistency between the 26 strains was 89.0%. The isolates of HPS-1, 2, 4, 5, 6, 7, 8, 10 and 11 had a 69-base deletion from 770 base pairs (bp) to 850 bp, which was infrequent in China. The phylogenetic tree showed that HPS-3 and HPS-8 had closer relationships with European and Japanese strains, but shared 98.7% nucleotide homology with the SW114 Japanese strain.
Twenty-three isolates of Pasteurella multocida were tested for susceptibility to six aminoglycoside agents and screened by polymerase chain reaction for the presence of aminoglycoside resistance genes. In addition, mutations in the resistance-determining region of strains showing a high level of induced resistance to spectinomycin strains were examined. Susceptibility testing showed that all of the isolates were resistant to at least two types of aminoglycosides, and that the most effective antimicrobial was spectinomycin. The resistance genes aphA1, strB and aacA4 were present in all 23 isolates. In the three induced spectinomycin-resistant strains, a 9-bp deletion in rpsE that encodes ribosomal protein S5 was detected.
The study was aimed to investigate biofilm forming ability of Mycoplasma hyopneumoniae and to determine the minimum biofilm eradication concentrations of antibiotics. Biofilm forming ability of six strains of M. hyopneumoniae was examined using crystal violet staining on coverslips. The results demonstrated an apparent line of biofilm growth in 3 of the strains isolated from swine with confirmed cases of enzootic pneumonia. BacLight bacterial viability assay revealed that the majority of the cells were viable after 336 hr of incubation. Moreover, M. hyopneumoniae persists in the biofilm after being exposed to 10 fold higher concentration of antibiotics than the minimum inhibitory concentrations in planktonic cells. To the best of our knowledge, this is the first report of biofilm formation in M. hyopneumoniae. However, comprehensive studies on the mechanisms of biofilm formation are needed to combat swine enzootic pneumonia caused by resistant M. hyopneumoniae.
The purpose of this research was to compare the accuracy of newly described P wave-related parameters (P wave area, Macruz index and mean electrical axis) with classical P wave-related parameters (voltage and duration of P wave) for the assessment of left atrial (LA) size in dogs with degenerative mitral valve disease. One hundred forty-six dogs (37 healthy control dogs and 109 dogs with degenerative mitral valve disease) were prospectively studied. Two-dimensional echocardiography examinations and a 6-lead ECG were performed prospectively in all dogs. Echocardiography parameters, including determination of the ratios LA diameter/aortic root diameter and LA area/aortic root area, were compared to P wave-related parameters: P wave area, Macruz index, mean electrical axis voltage and duration of P wave. The results showed that P wave-related parameters (classical and newly described) had low sensitivity (range=52.3 to 77%; median=60%) and low to moderate specificity (range=47.2 to 82.5%; median 56.3%) for the prediction of left atrial enlargement. The areas under the curve of P wave-related parameters were moderate to low due to poor sensitivity. In conclusion, newly P wave-related parameters do not increase the diagnostic capacity of ECG as a predictor of left atrial enlargement in dogs with degenerative mitral valve disease.
Canine histiocytic sarcoma (HS) is a malignancy originating from the histiocytic cell lineage and characterized by poor response to chemotherapy and short survival time. Mutation of the TP53 gene and its association with poor prognosis has been reported in several canine tumors. However, the mutation of this gene has not been investigated in canine HS. The aim of this study was to examine a TP53 gene mutation in dogs with HS. Aberrations of the TP53 gene were examined by polymerase chain reaction-single strand conformational polymorphism analysis and DNA sequence analysis, revealing mutations of the TP53 gene in 12 (46%) of 26 dogs affected by HS. The incidence of the TP53 gene mutation was relatively high in canine HS compared with other canine tumors. Among these mutations, 10 of 12 dogs (83%) with a TP53 gene mutation harbored the same mutation: a 2-base (AT) insertion in exon 5, resulting in the introduction of a stop codon (c.446_447insAT, p.Tyr150SerfsX8). Further studies are needed to examine the functional change due to the mutation and its association with the pathogenesis of canine HS.
Short chain fatty acids (SCFAs) play an important role in the maintenance of colonic homeostasis, and their depletion has been reported in various gastrointestinal disorders. Inflammatory colorectal polyps (ICRPs) are a recently recognized disease specific to miniature dachshunds (MDs), and fecal dysbiosis with a reduction of SCFA-producing bacteria has been reported with this disease. Therefore, this study was performed based on the hypothesis that a reduced SCFA concentration associates with the development of ICRPs. We recruited 11 ICRP-affected MDs and 25 control MDs. Their fecal SCFA concentrations and bacterial proportions were quantified using high performance liquid chromatography and quantitative real-time PCR, respectively. The feces of ICRP-affected MDs contained lower amounts of propionic acid and lower proportions of Bifidobacterium than the feces of control MDs. Furthermore, fecal proportions of Bifidobacterium, Firmicutes and Lactobacillus exhibited significant positive correlations with fecal concentrations of total SCFAs and/or propionic acid; fecal Escherichia coli proportions correlated negatively with fecal concentrations of total SCFAs, as well as acetic, propionic and butyric acid. This result indicates an association between fecal dysbiosis and fecal SCFA concentrations; these phenomena may contribute to ICRP pathogenesis in MDs. Potential therapeutic targeting of the reduced propionic acid concentration using probiotics, prebiotics or SCFA enemas merits further study.
The aim of the present study was to determine changes in body iron storage in adult dogs following phlebotomy. We performed repeated phlebotomies by removing 1% body weight (approximately 10% of the total blood volume) weekly for a total of 12 times using adult beagle dogs without an iron-restricted diet. After treatment, stored iron was decreased, as demonstrated by gradual reductions in serum ferritin levels and hepatic iron contents. Anemia and abnormalities in blood chemistry analysis were not observed; therefore, this method was considered safe and useful for control of stored iron levels in adult dogs.
Serum concentrations of non-esterified fatty acids (NEFA) and very low-density lipoprotein (VLDL) in close-up dairy cattle were compared in relation to parity. Data were obtained from 37 nulli/primiparous (NP) and 24 multiparous (MU, parity: 2–7) cows between 14 days and 1 day prepartum. A positive correlation (r=0.684, P<0.01) was found between serum NEFA and VLDL concentrations in NP cows. Among the VLDL constituents, the NEFA concentration was particularly correlated with the triglyceride (TG) concentration (r=0.658, P<0.01). However, no significant correlation was found between the concentrations of NEFA and VLDL or VLDL-TG in MU cows (r=−0.028 and 0.307). These results suggest the presence of higher hepatic secretion of NEFA-derived VLDL in NP cows.
This study evaluated the accuracy of a newly developed veterinary portable blood glucose meter (PBGM) with hematocrit correction in dogs and cats. Sixty-one dogs and 31 cats were used for the current study. Blood samples were obtained from each dog and cat one to six times. Acceptable results were obtained in error grid analysis between PBGM and reference method values (glucose oxidation methods) in both dogs and cats. Bland–Altman plot analysis revealed a mean difference between the PBGM value and reference method value of −1.975 mg/dl (bias) in dogs and 1.339 mg/dl (bias) in cats. Hematocrit values did not affect the results of the veterinary PBGM. Therefore, this veterinary PBGM is clinically useful in dogs and cats.
A 1-year-old neutered male Pekingese was presented for evaluation and further treatment of cluster seizures. The dog had behavioral abnormalities, and a prosencephalic lesion was suspected following neurological examination. The dog showed signs of learning difficulty. Magnetic resonance imaging of the brain revealed a remarkably smooth cerebral cortex with a reduced number of gyri, as well as a cystic lesion associated with the quadrigeminal cistern. A diagnosis of lissencephaly, concurrent with a quadrigeminal cisternal cyst, was made. High-dose and multiple anticonvulsants were necessary to control the seizures. This is the first report of lissencephaly in a Pekingese.
Gammaherpesviruses (GHVs) are members of an emerging subfamily of the family Herpesviridae. A recent study identified a novel GHV in domestic cats (Felis catus GHV1, FcaGHV1), and epidemiological surveys have found that FcaGHV1 is distributed worldwide. In this study, we investigated the prevalence of GHVs in domestic cats in Japan with a molecular epidemiological survey. Blood samples were collected from 1,738 domestic cats and GHV-derived DNA was detected with PCR in 1.3% (23/1,738) of the Japanese domestic cats. The FcaGHV1 detected in this study was very similar to FcaGHV1 detected in a domestic cat in North America. Older age (>5 years old) and Feline immunodeficiency virus infection were identified as risk factors for GHV infection.
A 10-month-old male Welsh Corgi with a history of acute blindness underwent neuro-ophthalmological testing and magnetic resonance imaging (MRI). Vision testing revealed complete visual deficits but the electroretinograph and pupillary light reflex were normal in both eyes. The motor and sensory functions of the eyelids and eyes were also normal. The MRI revealed compression of the optic chiasm caused by severe ventriculomegaly in the lateral and third ventricles. Such lesions are associated with inflammatory stenotic lesions in the mesencephalic aqueduct. Moderate neutrophilic pleocytosis was observed during cerebrospinal fluid analysis and Acinetobacter lwoffii was isolated, leading to a diagnosis of Acinetobacter-positive obstructive hydrocephalus. This is the first reported case of culture-proven Acinetobacter-associated postencephalitic hydrocephalus with acute blindness in a dog.
Progressive rod-cone degeneration (PRCD) is an autosomal recessive disease caused by c.5G>A mutation of the PRCD exon 2. This mutation has been identified in various breeds, including Labrador Retriever. The present study aimed to examine the allelic frequency of PRCD in Labrador Retrievers in Japan. A domestic and a guide dog population were genotyped for PRCD using polymerase chain reaction-restriction fragment length polymorphism. The allelic frequency of c.5G>A in domestic and guide dog populations (0.114 and 0.026, respectively) differed significantly. The allele with c.5G>A mutation appeared to spread widely in the domestic population as compared to that in the guide dog population. This might be the result of mating control for PRCD in the guide dog population.
Burdock (BD) is a common vegetable with many pharmacological properties. However, few studies have examined the effect of BD on exercise performance and physical fatigue. We aimed to evaluate the potential beneficial effects of BD on fatigue and ergogenic functions following physical challenge in mice. Methods: Male ICR mice were divided into four groups to receive either vehicle, or BD at 348.5, 697 or 1,742.5 mg/kg/day, by daily oral gavage for 4 weeks. Exercise performance and fatigue were evaluated from forelimb grip strength, exhaustive swimming time, and post-exercise levels of physical fatigue-related biomarkers serum lactate, ammonia, glucose, and creatine kinase (CK). Results: BD supplementation elevated endurance and grip strength in a dose-dependent manner. It also significantly decreased lactate, ammonia, and CK levels after physical challenge. In addition, BD supplementation had few subchronic toxic effects. Conclusions: Supplementation with BD has a wide spectrum of bioactive effects, including health promotion, performance improvement, and fatigue reduction.
An evaluation of mouse red blood cell (RBC) and platelet (PLT) counting with an automated hematology analyzer was performed with three strains of mice, C57BL/6 (B6), BALB/c (BALB) and DBA/2 (D2). There were no significant differences in RBC and PLT counts between manual and automated optical methods in any of the samples, except for D2 mice. For D2, RBC counts obtained using the manual method were significantly lower than those obtained using the automated optical method (P<0.05), and PLT counts obtained using the manual method were higher than those obtained using the automated optical method (P<0.05). An automated hematology analyzer can be used for RBC and PLT counting; however, an appropriate method should be selected when D2 mice samples are used.
A 7-year-old castrated male ferret developed unilateral cervical lymphadenomegaly over a 1-month period. Histological examination revealed proliferation of tumor cells in a diffuse and partially nodular pattern. The tumor cells were predominantly Hodgkin cells and binucleated Reed-Sternberg cells, characterized by abundant, clear, vacuolated cytoplasm, pleomorphic, ovoid nuclei with thick nuclear membranes and distinct nucleoli. Multinucleated cells, resembling lymphocytic and histiocytic (L&H) cells, were also observed. Immunohistochemically, the tumor cells expressed Pax-5, BLA-36 and vimentin. A small population of the tumor cells expressed CD20. This case showed proliferation of Hodgkin/Reed-Sternberg cells in conjunction with L&H cells that were histologically analogous to feline Hodgkin’s-like lymphoma. However, Pax-5 and BLA-36 expression along with rare CD20 expression were consistent with classical Hodgkin’s lymphoma in humans.
A white, lobular mass was found in the right ovary of a pregnant Risso’s dolphin (Grampus griseus) at necropsy. The mass was unilateral and occupied most of the pre-existing ovarian tissue. Histologically, the mass was composed of diffuse sheets of polyhedral cells with abundant eosinophilic cytoplasm and oval nuclei, separated by fibrous connective tissue. Only a few ovarian follicles were observed at the periphery of the mass. Immunohistochemically, the large eosinophilic cells were positive for vimentin and negative for pan-cytokeratins. Based on the histopathological features, the present case was diagnosed as luteoma. In human medicine, luteoma of pregnancy, a tumor-like proliferative lesion occurring in pregnant women, is well described. In veterinary medicine, luteoma associated with pregnancy has never been described. The present study would provide useful information for understanding the characteristics of luteoma in animals.
This study reports on two Hanwoo (a native Korean breed of cattle) calves, a 3- and 6-month-old presenting with diarrhea, anorexia and blindness. Ophthalmoscopic examination revealed bilateral papilledema in both calves. Reverse-transcription polymerase chain reaction tests for bovine viral diarrhea virus, rotavirus and coronavirus were all negative. The levels of serum vitamin A in the two affected calves were 0.317 µg/dl and 0.481 µg/dl, respectively. These values are much lower than the normal vitamin A levels; therefore, the calves were diagnosed with hypovitaminosis A.
Fur seal feces-associated circular ssDNA virus (FSfaCV) was discovered in a pig for the first time in Japan using a next-generation sequencer with duplex-specific nuclease. Full genome of the virus showed approximately 92% similarity to FSfaCVs from New Zealand fur seals. Furthermore, we investigated the prevalence of the ssDNA virus in 85 piglets in Japan, and 65 piglets were positive (76%) for the virus.
Acerodon jubatus (the Golden-Crowned flying fox) is an endemic species in the Philippines, which was suspected to be a host of the Reston strain of the Ebola virus. As nocturnal animals, the flying foxes spend daytime at the roosting site, which they use for self-maintenance and reproduction. To understand the variation in diurnal behavior and time allocation for various activities in the Golden-Crowned flying fox, we investigated their daytime behavior and activity budget using instantaneous scan sampling and all occurrence focal sampling. Data collection was performed from 07:00 to 18:00 hr during January 8–17, 2017. The most frequent activity was sleeping (76.3%). The remaining activities were wing flapping (5.0%), self-grooming (4.2%), hanging relaxation (3.4%), wing spread (2.9%), movement (2.4%), mating/courtship (2.4%), aggression (1.9%), hanging alert (1.2%), excretion (0.1%) and scent marks (0.05%). The frequency of sleeping, wing flapping, self-grooming, hanging relaxation, aggression, mating/courtship and movement behaviors changed with the time of the day. Females allocated more time for resting than males, while males spent more time on the activities that helped enhance their mating opportunities, for example, movement, sexual activity and territorial behavior.
The objective of this study was to measure differences between arterial and venous blood gas parameters and to evaluate whether arterial blood gas values can be estimated from venous blood in Asiatic black bears (ABBs). Twelve healthy captive ABBs (8 males and 4 females; 8–16 years; 76.8–220 kg) were included in this study. The bears were immobilized with medetomidine and zolazepam-tiletamine using a dart gun. Arterial and venous samples were collected simultaneously at 5 and 35 min after recumbency (5- and 35-min points). Partial pressure of oxygen (PO2), partial pressure of carbon dioxide (PCO2), pH, bicarbonate (HCO3−), total carbon dioxide (TCO2), oxygen saturation of hemoglobin (SO2) and base excess (BEecf) were analyzed using a portable blood gas analyzer. There was no marked difference in measured and calculated variables over time in both venous and arterial blood except for PO2. However, arterial PO2, SO2 and pH were significantly higher and arterial PCO2, TCO2 and HCO3− were lower than those of venous samples at both 5- and 35-min points. In the regression analysis to estimate arterial values from venous values, PCO2, TCO2, HCO3−, BEecf and pH significantly showed over 0.45 in coefficient of determination value (R2), and there were little differences between actual and predicted arterial values. Although there were limits in venous gas values replaced those of arterial blood, if we could not get the arterial samples, the regression formulas for arterial values from venous blood in this study would be useful clinically, except for PO2 and SO2.
A female Indian star tortoise (Geochelone elegans) was evaluated for anorexia and suspected coelomic masses. Clinical examination indicated follicular stasis. The tortoise was anesthetized and placed in dorsal left lateral recumbency for a right prefemoral approach. The ovaries and oviducts were exposed through the right prefemoral incision. The ovarian vasculature, the mesovarium, the oviduct, mesosalpinx and associated vasculature were ligated and transected. Bilateral oophorosalpingectomy was performed through the incision, without coelioscopy. Since then, the same procedure has been performed in five other tortoises, and all recovered well. These results suggest that bilateral oophorosalpingectomy, performed through a prefemoral incision, without coelioscopy, is a safe and practical approach for treating follicular stasis in tortoises.
An approximately two-year-old, male 6.1 kg body weight, Korean wild raccoon dog (Nyctereutes procyonoides koreensis) was captured by the wildlife medical rescue center of Kangwon National University. Upon physical examination, the heart rate was 87 beats per min and there were no clinical signs. The hematological, and blood biochemical profiles revealed no remarkable findings; however, thoracic radiographs showed cardiac enlargement, especially in the right atrium. On electrocardiogram, sinus node dysfunction and bradyarrhythmia were revealed. Echocardiography showed a left-to-right shunting atrial septal defect. Based on these findings, this Korean wild raccoon dog was diagnosed with atrial septal defect. This is the rare case report of atrial septal defect in wildlife.