Listeria monocytogenes septicemia in a Thoroughbred foal.

Listeria monocytogenes septicemia was diagnosed in a 6-day-old Thoroughbred foal. Primary clinical signs included fever, depression, diarrhea, and respiratory distress. Hematologic abnormalities included leukopenia, neutropenia, degenerative left shift, and hyperfibrinogenemia. Clinical chemistry and blood gas abnormalities included metabolic acidosis, hypoxemia, hypocapnia, hypoglycemia, and hyponatremia. Despite aggressive therapeutic intervention and intensive care, the foal died within 12 hours of admission. A postmortem examination was performed, and the primary gross lesion was bilaterally severe, focally extensive bronchopneumonia. Histopathology revealed severe subacute multifocal suppurative bronchopneumonia with necrotizing vasculitis and intralesional coccobacilli. Cultures of blood collected at admission and immediately prior to death were positive for L. monocytogenes, as were cultures obtained from lung and liver at necropsy. Immunohistochemical examination of formalin-fixed tissues revealed abundant intra- and extracellular L. monocytogenes antigen within the lung and intravascularly in multiple organs.     

Listeria monocytogenes gastroenteritis in sheep

Extract

Listeria monocytogenes is widely distributed in the environment of farm animals. It is found in soil, faeces and nasal secretions of healthy animals, water troughs and animal feeds. Under certain conditions it becomes pathogenic, causing serious disease in cattle and sheep. Most commonly it causes meningoencephalitis but, on occasion, septicaemic listeriosis results in abortion, and more recently it has been associated with gastroenteritis.     

Isolation of Listeria monocytogenes from Goat Cheese Associated with a Case of Listeriosis in Goat

Listeria monocytogenes was isolated from the brain of a goat, which was euthanized due to listeriosis. A few weeks later a similar subtype of L. monocytogenes was isolated from an on-farm manufactured fresh cheese which did not contain any milk from the goat which had suffered from listeriosis. A similar subtype was also found on 1 of the shelves in the refrigerator where cheeses were stored. Prior to the onset of listeriosis, 1 fresh cheese had been made of milk from the actual goat, which may have excreted L. monocytogenes in her milk. Thus, the cheese made of this milk may have contaminated the shelves in the refrigerator which then has served as a Listeria reservoir for new cheeses during several weeks.     

Listeria monocytogenes and Escherichia coli septicemia and meningoencephalitis in a 7-day-old llama

Listeria monocytogenes and Escherichia coli were isolated from blood collected on presentation and tissues samples taken postmortem. Listeria monocytogenes was isolated from cerebrospinal fluid collected antemortem. The importance of passive transfer of immunity, the subtlety of neurologic signs in early meningitis, and considering blood-CSF penetration in antimicrobial selection are discussed.     

ELISA testing for common food antigens in four dry dog foods used in dietary elimination trials

This study evaluated four over the counter venison dry dog foods available from one on-line retail vendor for potential contamination with common known food allergens: soy, poultry or beef. An amplified, double sandwich type enzyme linked immunosorbent assay (ELISA) test of soy, poultry and beef proteins were performed by an independent accredited food laboratory. The ELISA test for poultry protein was found to be unreliable when testing in dry dog foods because false negatives occurred. ELISA testing of control diets for both soy and beef proteins performed as expected and could be useful in antigen testing in dry dog foods. Three of the four over the counter (OTC) venison canine dry foods with no soy products named in the ingredient list were ELISA positive for soy; additionally one OTC diet tested positive for beef protein with no beef products listed as an ingredient list. One OTC venison diet was not found to be positive for soy, poultry or beef proteins. However, none of the four OTC venison diets could be considered suitable for a diagnostic elimination trial as they all contained common pet food proteins, some of which were readily identifiable on the label and some that were only detected by ELISA. Therefore, if the four OTC venison products selected in this study are representative of OTC products in general, then the use of OTC venison dry dog foods should not be used during elimination trials in suspected food allergy patients.     

石河子地区动物性食品中单核细胞增生李斯特菌的检测

目的了解新疆石河子地区动物性食品中单核细胞增生李斯特氏菌(LM)污染状况。方法在石河子地区选取5个具有代表性动物性食品零售点,对最常食用的生鲜猪肉、牛肉、羊肉、鸡肉、冻鸡肉、冻虾和冻带鱼8类动物性食品进行随机采样,采用病原分离培养和PCR法对样品中的单核细胞增生李斯特氏菌进行检测。结果检测8类249份食品样品,细菌分离鉴定阳性样品12份,平均阳性率4.82%;PCR法检测阳性样品36份,平均阳性率为14.46%。结论石河子动物性食品中LM的污染比较普遍,尤以冻鸡肉和冻虾LM污染较重,新鲜猪肉、牛肉和羊肉LM污染程度较轻。     

单核细胞增生性李斯特菌感染ICR小鼠模型的建立

单核细胞增生性李斯特菌(Listeria monocytogenes,LM)是一种人畜共患食源性致病菌,能引起人和动物较为严重的感染症状。现广泛使用具有免疫活性的小鼠模型测定半数致死量(LD₅₀)来评价不同LM菌株的致病性。为建立LM的ICR小鼠模型,本研究采用1/2a血清型的N21 LM菌株,分别以10⁶、10⁷、10⁸、10⁹和10¹⁰ CFU的剂量口腔灌注感染6周龄ICR小鼠,每组10只;另取10只接种PBS作为对照组,测定LM对ICR小鼠的LD₅₀;另取40只小鼠,平均分为2组,公母各半,以测定的LD₅₀剂量接种LM,分别对各组小鼠临床症状、组织病理变化、体重变化及组织中细菌载量进行评价。结果发现,N21 LM菌株对ICR小鼠的LD₅₀为10^9.25 CFU;感染周期为10 d左右,感染小鼠出现被毛粗糙、精神萎靡、阴茎垂出及体重下降等临床症状。组织病理学分析结果显示,肝脏先后出现实质内灶状细菌团块、形成血栓、细胞坏死等;脾脏主要表现为白髓内淋巴细胞减少;肺脏主要表现为纤维素性肺炎。菌落计数和Real-time PCR的检测结果发现肝脏中细菌载量最高,脾脏次之。结果表明,ICR小鼠能作为单核细胞增生性李斯特菌的感染模型。本试验结果为研究LM的致病机制、疫苗研究及抗菌肽转基因小鼠抗LM的评价奠定了基础。     

Septic peritonitis in a dog caused by Anaerobiospirillum succiniproducens

This is the first reported case of septic peritonitis caused by Anaerobiospirillum succiniproducens in a dog. The infection was associated with marked exfoliation of reactive mesothelial cells into the abdominal fluid mimicking neoplasia. The source of the infection was not determined but was presumed to be of gastrointestinal origin as A succiniproducens is part of the normal gastrointestinal flora of dogs. Anaerobiospirillum spp. have been previously reported as causing diarrhea and bacteremia in people, particularly if immunocompromised; however, there were no indicators for a compromised immune system in this dog.     

Systemic Listeria monocytogenes infection and concurrent pleural mesothelioma in a cat

Herein we describe a rare case of systemic Listeria monocytogenes infection with concurrent pleural mesothelioma in a stray cat that was found dead and submitted for autopsy. Gross pathology changes consisted of thoracic clear yellow fluid admixed with suspended fibrin strands; clear-to-tan, variably sized, <3 mm diameter pulmonary nodules; and enlargement of the submandibular, retropharyngeal, and prescapular lymph nodes. Histologic changes consisted of extensive areas of suppurative inflammation and necrosis with mineralization that partially effaced the pulmonary parenchyma and lymph nodes. Random, distinct necrotic foci were present throughout the hepatic parenchyma. Extending from the pleura, within perinecrotic alveolar spaces, and infiltrating the submandibular, retropharyngeal, and prescapular lymph nodes were dense sheets of neoplastic epithelioid cells with moderate pleomorphism and occasional karyomegaly and multinucleation. Neoplastic cells exhibited immunolabeling for pancytokeratin AE1/AE3 and vimentin, consistent with pleural mesothelioma. Aerobic bacterial culture of lung yielded heavy growth of L. monocytogenes. Immunohistochemistry (IHC) for L. monocytogenes revealed clusters of bacteria in the lung, lymph node, and liver. Pathologic changes were consistent with systemic listeriosis, confirmed by bacterial culture and IHC, and concurrent pleural mesothelioma.     

产单核细胞李氏杆菌突变株的感染动力学研究

以BALB/c小鼠为实验动物模型,对actA基因和plcB基因双缺失的产单核细胞李氏杆菌（LM）yzuLM1-2菌株进行感染动力学研究。分别用减毒突变株yzuLM1-2和野生型菌株yzuLM4给BALB/c小鼠静脉注射或灌服,并对脏器中LM的分布动态进行测定。结果显示,在显著高于野生型菌株感染剂量的条件下注射或灌服接种后,减毒突变株组小鼠肝和脾中的LM数量迅速下降,被清除的速度显著快于野生型菌株组。溶血素（LLO）抗体的测定结果显示,减毒突变株菌能和野生型菌同样激发较高水平的抗体。小鼠免疫保护试验结果显示,减毒突变株免疫组对同种血清型LM的攻击具有较好的免疫保护力,可达100%。结果表明,yzuLM1-2突变株侵袭力下降,致病力降低,能激发较高水平的抗体产生,可以作为预防动物李氏杆菌病的候选疫苗菌株,并为用作运送外源保护性抗原的载体提供了材料。     

Cardiopulmonary arrest and resuscitation following an extradural injection in a normovolemic dog

Objective – To describe general anesthesia and successful resuscitation of a dog developing asystole and apnea during extradural injection of local anesthetic and an opioid. Case Summary – A Beagle with a ruptured cranial cruciate was premedicated with acepromazine and methadone. Anesthesia was induced with propofol and, after endotracheal intubation, maintained using isoflurane in oxygen. During extradural injection of a mixture of lidocaine, bupivacaine, and morphine the dog developed apnea and asystole. Cardiopulmonary cerebral resuscitation was started promptly and the dog was successfully resuscitated. New Information Provided – Asystole and apnea are possible serious side effects of extradural anesthesia in dogs. With adequate monitoring and early detection successful resuscitation is possible.     

First case of a dog infected with Aspergillus (Phialosimplex) caninus in Australasia

ABSTRACT

Case history: A 2-year-old Rottweiler dog from Perth (WA, Australia) was referred for assessment of a chronic productive cough and weight loss.

Clinical findings: Severely enlarged bilateral superficial cervical lymph nodes and severely enlarged abdominal organs were present. The body condition score was poor and there was moderate muscle wasting. Thoracic and abdominal computed tomography images revealed severe diffuse enlargement of thoracic and abdominal lymph nodes, hepatomegaly and diffuse splenomegaly. A diffuse bronchial pattern with severe multifocal saccular bronchiectasis was identified in the lungs.

Diagnostic findings: Fungal organisms were seen within macrophages on cytological preparations and on histopathological sections of biopsies of the superficial cervical lymph node. Macrophages contained intracytoplasmic, non-filamentous round-to-ovoid organisms, which varied in size from 5–30?µm in diameter with variable morphology. Budding was not observed, and no hyphae were present. Fungal culture of lymph node tissue resulted in growth of Aspergillus (Phialosimplex) caninus which was confirmed by amplification and sequencing of a segment of the 16S-23S rRNA internal transcribed spacer. Concurrent bacterial bronchitis was diagnosed on culture of broncho-alveolar fluid.

Diagnosis: Disseminated aspergillosis caused by Aspergillus caninus.

Clinical relevance: This is believed to be the first report of infection caused by A. caninus in a dog in Australasia. The dog was treated with itraconazole for 7 months and was still alive 7 months after the start of treatment.     

Prevalence of dog erythrocyte antigens in retired racing Greyhounds

Background: Blood groups in dogs are designated as dog erythrocyte antigen (DEA) 1.1, 1.2, 3, 4, 5, 7, and Dal. There is limited information about the frequency of different antigens in Greyhound dogs, despite their frequent use as blood donors. Objectives: The aims of this study were to determine the frequencies of DEA 1.1, 1.2, 3, 4, 5, and 7 in Greyhounds, to compare the frequencies with those of non‐Greyhound dogs, and to evaluate the presence of naturally occurring anti‐DEA antibodies. Methods: Blood was collected from 206 Greyhound and 66 non‐Greyhound dogs being screened as potential blood donors. Blood‐typing was performed at Animal Blood Resources International by tube agglutination utilizing polyclonal anti‐DEA antibodies. Results: Of the Greyhound dogs, 27/206 (13.1%) were positive for DEA 1.1, and this frequency was significantly lower (P<.0001) than for non‐Greyhound dogs of which 40/66 (60.6%) were DEA 1.1‐positive. The frequency of positivity for both DEA 1.1 and 1.2 was also lower in Greyhounds (P<.0001). There were no significant differences between Greyhounds and non‐Greyhounds for DEA 1.2, 3, 4, 5, or 7. All 137 dogs (113 Greyhounds and 24 non‐Greyhounds) that were evaluated for naturally occurring anti‐DEA antibodies in serum were negative. A higher percentage of Greyhound dogs (57.3%, 118/206) were considered “universal donors” (negative for all DEAs except DEA 4) compared with non‐Greyhound dogs (28%, 13/46). Conclusion: The frequency of positivity for DEA 1.1 in our population of Greyhounds was significantly lower than previously reported for dogs. Furthermore, a large majority of Greyhounds met the criteria for universal donors.