Xavier Rafael Gariglio Clark, da Silva Paloma Helena Sanches, Trindade Hanna Dornelas, Carvalho Gabriela Muniz, Nicolino Rafael Romero, Freitas Patrícia Maria Coletto, Silva Rodrigo Otávio Silveira
Affiliation Veterinary School, Federal University of Minas Gerais, Antônio Carlos Avenue 6627, 31270-090 Belo Horizonte, Brazil.
Vet Sci. 2022 May 22;9(5):245. doi: 10.3390/vetsci9050245.
Despite its high frequency and clinical relevance, the pathogenesis of canine pyometra remains poorly understood. The most accepted hypothesis is that bacteria involved ascend from the intestinal tract, causing the uterine infection. Extraintestinal pathogenic (ExPEC) is the most frequent pathogen in canine pyometra, accounting for 57-100% of cases. The aim of the present study was to determine the frequency of phylogenetic groups and virulence factors in strains isolated from the uterine and rectal swabs of bitches with pyometra ( = 72) and from rectal swabs from healthy bitches fed commercial dry feed ( = 53) or a raw meat-based diet (RMBD; = 38). A total of 512 strains of were isolated and divided into five categories according to the origin of the sample: 120 isolates from the uterine content of dogs with pyometra, 102 from the feces of bitches with pyometra, 75 from the feces of bitches without pyometra, 130 feces samples from healthy dogs fed commercial feed, and 85 feces samples from healthy dogs fed a raw meat-based diet. strains belonging to the B2 phylogroup and positive for virulence factor genes associated with adhesion (fimbriae type P []) and production of toxins (α-hemolysin [] and uropathogenic specific protein []) predominated in the uterine content and rectal swabs of bitches with pyometra. Interestingly, a lower growth rate of from the B2 phylogroup was observed in dogs fed a RMBD than in those fed commercial dry feed. The present study suggests that intestinal colonization by certain types of could be a risk factor for the occurrence of pyometra in bitches and that diet can influence intestinal colonization by such strains.
尽管犬子宫蓄脓发病率高且具有临床相关性，但其发病机制仍知之甚少。目前最被认可的假说是，相关细菌从肠道上行，引发子宫感染。肠道外致病性大肠杆菌（ExPEC）是犬子宫蓄脓中最常见的病原体，占病例的57%至100%。本研究的目的是确定从患有子宫蓄脓的母犬（n = 72）的子宫和直肠拭子以及喂食商业干饲料（n = 53）或生肉饮食（RMBD；n = 38）的健康母犬的直肠拭子中分离出的菌株的系统发育群和毒力因子的频率。共分离出512株大肠杆菌，根据样本来源分为五类：120株来自患有子宫蓄脓的犬的子宫内容物，102株来自患有子宫蓄脓的母犬的粪便，75株来自未患子宫蓄脓的母犬的粪便，130份来自喂食商业饲料的健康犬的粪便样本，以及85份来自喂食生肉饮食的健康犬的粪便样本。属于B2系统发育群且与黏附（P型菌毛[FimP]）和毒素产生（α-溶血素[HlyA]和泌尿道致病性特异性蛋白[UspA]）相关的毒力因子基因呈阳性的大肠杆菌菌株在患有子宫蓄脓的母犬的子宫内容物和直肠拭子中占主导地位。有趣的是，与喂食商业干饲料的犬相比，喂食生肉饮食的犬中B2系统发育群的大肠杆菌生长速率较低。本研究表明，某些类型的大肠杆菌在肠道内定植可能是母犬发生子宫蓄脓的一个风险因素，并且饮食会影响此类菌株在肠道内的定植。
