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We describe three cases of osteoarticular infection (OAI) in young thoroughbred horses in which the causative organism was identified by MALDI-TOF as Kingella species . The pattern of OAI resembled that reported with Kingella infection in humans. Analysis by 16S rRNA PCR enabled construction of a phylogenetic tree that placed the isolates closer to Simonsiella and Alysiella species , rather than Kingella species . Average nucleotide identity (ANI) comparison between the new isolate and Kingella kingae and Alysiella crassa however revealed low probability that the new isolate belonged to either of these species. This preliminary analysis suggests the organism isolated is a previously unrecognised species., Competing Interests: Authors declare that there is no conflict of interests regarding the publication of this paper., (Copyright © 2020 Bernard J. Hudson et al.)

The bag-shelter moth, Ochrogaster lunifer Herrich-Schaffer (Lepidoptera: Notodontidae), is associated with a condition called equine amnionitis and fetal loss (EAFL) on horse farms in Australia. Setal fragments from O. lunifer larvae have been identified in the placentas of experimentally aborted fetuses and their dams, and in clinical abortions. The gregarious larvae build silken nests in which large numbers cohabit over spring, summer and autumn. The final instars disperse to pupation sites in the ground where they overwinter. Field-collected O. lunifer larvae, their nests and nearby soil were examined using light and electron microscopy to identify setae likely to cause EAFL and to determine where and how many were present. Microtrichia, barbed hairs and true setae were found on the exoskeletons of the larvae. True setae matching the majority of setal fragments described from equine tissue were found on third to eighth instar larvae or exuviae. The number of true setae increased with the age of the larva; eighth instars carried around 2.0-2.5 million true setae. The exuvia of the pre-pupal instar was incorporated into the pupal chamber. The major sources of setae are likely to be nests, dispersing pre-pupal larvae and their exuviae, and pupal chambers., (© 2015 The Royal Entomological Society.)

Pregnant mares were experimentally exposed to whole caterpillar or exoskeleton of the Processionary caterpillar (Ochrogaster lunifer) via gavage. Tissues were collected from resulting abortions and near or full-term pregnancies consisting of 13 aborted fetuses, 3 fetuses from treated euthanized mares, membranes of 5 foals, and organs from 3 foals. Three control membranes and 1 control fetus and membranes were examined. Caterpillar setal fragments were present in the allantochorion of the 3 fetuses from the euthanized mares and 11 of 12 aborted fetuses (92%) embedded in the chorion (villi or stroma) or allantois (vasculature or stroma). Placental locations of fragments ranged from the cervical pole region to the body encompassing the umbilical insertion and pregnant horn. Numbers in each fetus ranged from 1 to 7 fragments. Setae were present in the allantochorion from 2 to 22 days after the initial treatment. Acute to chronic active inflammation was present in all aborted fetuses, all euthanized fetuses, and within at least 1 tissue level (chorion, allantois, umbilical cord, or amnion) of the membranes from full-term foals. Amnionitis, funisitis, and allantoitis were present in 95% of the examined membranes. Pneumonia was present in 95% of the specimens, and bacteria were present histologically in 90.5% of the specimens with or without accompanying inflammation. The rapid migration of setae within 2 days after mare exposure suggests that direct setal migration into the fetal membranes is a likely initiating factor for equine amnionitis and fetal loss (EAFL)., (© The Author(s) 2014.)

Six pregnant Standardbred mares aged between 6 and 14 years were gavaged with 50 g or 100 g of suspended emulsified whole Processionary caterpillars (Ochrogaster lunifer) for 5 days during 2 experiments undertaken to study the etiology of equine amnionitis and fetal loss (EAFL). The 6 treated mares and 1 untreated mare were between 128 and 252 days gestation. Mare 1 (untreated) was euthanized on day 5 of the treatment period, while the treated mares were euthanized on days 2, 4, 8, 10, 12, and 24 days from their first treatment. Caterpillar setae were not found in the untreated mare. Setal fragments were present in all regions of the gastrointestinal tracts in all treated mares, the uteri and mesenteric lymph nodes of 5 mares, and the liver of 4 mares. Acute gastroenteritis of varying severity was present in all treated mares, and 5 of 6 mares had acute colitis and endometritis. Focal hyperplastic serositis was found in the duodenum, cecum, dorsal colon, and uteri of various mares occasionally with embedded setal fragments. Setal invasion of the mucosa evoked a range of lesions including superficial erosion to deep ulceration. Inflammation in deeper tissues ranged from unapparent to neutrophilic (microabscesses), eosinophilic, or mononuclear (microgranulomas). The finding of setal fragments within the uterus of experimental mares suggests that direct migration of setal fragments acting as a bacterial vector is a likely mechanism for the bacterial abortions that characterize equine amnionitis and fetal loss., (© The Author(s) 2013.)

Reasons for Performing Study: Equine amnionitis and fetal loss (EAFL) is an unusual form of abortion in mid- to late-gestation mares, first identified in Australia in 2004. It has been shown that both whole processionary caterpillars (Ochrogaster lunifer) and their shed exoskeletons can induce abortion in mares during midgestation. These abortions exhibited gross pathology and bacteriology results consistent with field cases of EAFL., Objectives: To determine whether exposure of mares to the shed exoskeletons of processionary caterpillars can induce abortion in the preplacentation (<35 days' gestation) and early placentation (45-60 days) stages of pregnancy., Study Design: In vivo experimental study., Methods: Mares less than 35 days' gestation and between 45 and 60 days' gestation were exposed to a slurry of shed processionary caterpillar exoskeletons by nasogastric intubation. Mares were monitored by clinical examination daily. Transrectal ultrasonography was performed daily (control and treated preplacentation mares, treated early placentation mares) or every second day (control early placentation mares). Uterine swabs were collected from mares that aborted. All live foals underwent a clinical examination. Placentas were examined, with sampling for bacteriology and histopathology if appropriate., Results: Abortions occurred in treated mares in both experiments without signs of impending abortion. One mare aborted in the embryonic stage experiment and 2 in the early placentation experiment. Embryonic and fetal death was detected on transrectal ultrasonography prior to abortion. In the early placentation experiment, one foal was born 5 weeks preterm and was very small, with laxity of the tendons in all limbs. Enteric or environmental bacteria, consistent with EAFL, were isolated from the mares that aborted. Focal mucoid placentitis lesions were present on the placentas of 2 treated mares, one from each experiment., Conclusions and Potential Relevance: Processionary caterpillar exposure may be associated with EAFL-related embryonic and early fetal loss in mares. Processionary caterpillars may also play a role in the occurrence of focal mucoid placentitis., (© 2013 EVJ Ltd.)

Reasons for Performing Study: In Australia, there have been recent reports of unusual abortions in mid- to late-gestation mares. These were clinically distinct from other recognised causes of pregnancy loss and the term 'equine amnionitis and fetal loss' (EAFL) was adopted to describe this syndrome. Initial investigations concluded that possible causal factors included the presence on affected stud farms of Processionary caterpillars (Ochrogaster lunifer)., Objectives: To determine if exposure of pregnant mares to Processionary caterpillars or their shed exoskeletons can induce EAFL., Methods: Processionary caterpillars and their shed exoskeletons were collected and stored frozen. Mid-gestation mares were dosed with a slurry of caterpillars or shed exoskeleton by nasogastric intubation. Their clinical responses and times to abortion were recorded. All aborted fetuses were autopsied and samples taken for bacteriological and virological culture and histopathology., Results: Intubating mares in mid-pregnancy with preparations of either whole Processionary caterpillars or shed caterpillar exoskeletons induced abortion with few impending clinical signs. The gross pathological and bacteriological findings of the aborted fetuses were similar to those observed in field cases of EAFL., Potential Relevance: Possible exposure to Processionary caterpillars should be considered when examining cases of fetal loss in the mare. The present results provide a starting point to further explore the aetiology and pathogenesis of EAFL., (© 2011 EVJ Ltd.)